Sample records for potential engineering applications

  1. Stirling engine application study

    NASA Technical Reports Server (NTRS)

    Teagan, W. P.; Cunningham, D.

    1983-01-01

    A range of potential applications for Stirling engines in the power range from 0.5 to 5000 hp is surveyed. Over one hundred such engine applications are grouped into a small number of classes (10), with the application in each class having a high degree of commonality in technical performance and cost requirements. A review of conventional engines (usually spark ignition or Diesel) was then undertaken to determine the degree to which commercial engine practice now serves the needs of the application classes and to detemine the nature of the competition faced by a new engine system. In each application class the Stirling engine was compared to the conventional engines, assuming that objectives of ongoing Stirling engine development programs are met. This ranking process indicated that Stirling engines showed potential for use in all application classes except very light duty applications (lawn mowers, etc.). However, this potential is contingent on demonstrating much greater operating life and reliability than has been demonstrated to date by developmental Stirling engine systems. This implies that future program initiatives in developing Stirling engine systems should give more emphasis to life and reliability issues than has been the case in ongoing programs.

  2. Ceramic applications in the advanced Stirling automotive engine

    NASA Technical Reports Server (NTRS)

    Tomazic, W. A.; Cairelli, J. E.

    1977-01-01

    The ideal cycle, its application to a practical machine, and the specific advantages of high efficiency, low emissions, multi-fuel capability, and low noise of the stirling engine are discussed. Certain portions of the Stirling engine must operate continuously at high temperature. Ceramics offer the potential of cost reduction and efficiency improvement for advanced engine applications. Potential applications for ceramics in Stirling engines, and some of the special problems pertinent to using ceramics in the Stirling engine are described. The research and technology program in ceramics which is planned to support the development of advanced Stirling engines is outlined.

  3. Progress toward determining the potential of ODS alloys for gas turbine applications

    NASA Technical Reports Server (NTRS)

    Dreshfield, R. L.; Hoppin, G., III; Sheffler, K.

    1983-01-01

    The Materials for Advanced Turbine Engine (MATE) Program managed by the NASA Lewis Research Center is supporting two projects to evaluate the potential of oxide dispersion strengthened (ODS) alloys for aircraft gas turbine applications. One project involves the evaluation of Incoloy (TM) MA-956 for application as a combustor liner material. An assessment of advanced engine potential will be conducted by means of a test in a P&WA 2037 turbofan engine. The other project involves the evaluation of Inconel (TM) MA 6000 for application as a high pressure turbine blade material and includes a test in a Garrett TFE 731 turbofan engine. Both projects are progressing toward these engine tests in 1984.

  4. Evaluation of heat engine for hybrid vehicle application

    NASA Technical Reports Server (NTRS)

    Schneider, H. W.

    1984-01-01

    The status of ongoing heat-engine developments, including spark-ignition, compression-ignition, internal-combustion, and external-combustion engines is presented. The potential of engine concepts under consideration for hybrid vehicle use is evaluated, using self-imposed criteria for selection. The deficiencies of the engines currently being evaluated in hybrid vehicles are discussed. Focus is on recent research with two-stroke, rotary, and free-piston engines. It is concluded that these engine concepts have the most promising potential for future application in hybrid vehicles. Recommendations are made for analysis and experimentation to evaluate stop-start and transient emission behavior of recommended engine concepts.

  5. Incorporating unnatural amino acids to engineer biocatalysts for industrial bioprocess applications.

    PubMed

    Ravikumar, Yuvaraj; Nadarajan, Saravanan Prabhu; Hyeon Yoo, Tae; Lee, Chong-Soon; Yun, Hyungdon

    2015-12-01

    The bioprocess engineering with biocatalysts broadly spans its development and actual application of enzymes in an industrial context. Recently, both the use of bioprocess engineering and the development and employment of enzyme engineering techniques have been increasing rapidly. Importantly, engineering techniques that incorporate unnatural amino acids (UAAs) in vivo has begun to produce enzymes with greater stability and altered catalytic properties. Despite the growth of this technique, its potential value in bioprocess applications remains to be fully exploited. In this review, we explore the methodologies involved in UAA incorporation as well as ways to synthesize these UAAs. In addition, we summarize recent efforts to increase the yield of UAA engineered proteins in Escherichia coli and also the application of this tool in enzyme engineering. Furthermore, this protein engineering tool based on the incorporation of UAA can be used to develop immobilized enzymes that are ideal for bioprocess applications. Considering the potential of this tool and by exploiting these engineered enzymes, we expect the field of bioprocess engineering to open up new opportunities for biocatalysis in the near future. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Potential of Diesel Engine, Diesel Engine Design Concepts, Control Strategy and Implementation

    DOT National Transportation Integrated Search

    1980-03-01

    Diesel engine design concepts and control system strategies are surveyed with application to passenger cars and light trucks. The objective of the study is to indicate the fuel economy potential of the technologies investigated. The engine design par...

  7. Composite engines for application to a single-stage-to-orbit vehicle

    NASA Technical Reports Server (NTRS)

    Bendot, J. G.; Brown, P. N.; Piercy, T. G.

    1975-01-01

    Seven composite engines were designed for application to a reusable single-stage-to-orbit vehicle. The engine designs were variations of the supercharged ejector ramjet engine. The resulting performance, weight, and drawings of each engine form a data base for establishing a potential of this class of composite engine to various missions, including the single-stage-to-orbit application. The impact of advanced technology in the design of the critical fan turbine was established.

  8. Potential for Imaging Engineered Tissues with X-Ray Phase Contrast

    PubMed Central

    Appel, Alyssa; Anastasio, Mark A.

    2011-01-01

    As the field of tissue engineering advances, it is crucial to develop imaging methods capable of providing detailed three-dimensional information on tissue structure. X-ray imaging techniques based on phase-contrast (PC) have great potential for a number of biomedical applications due to their ability to provide information about soft tissue structure without exogenous contrast agents. X-ray PC techniques retain the excellent spatial resolution, tissue penetration, and calcified tissue contrast of conventional X-ray techniques while providing drastically improved imaging of soft tissue and biomaterials. This suggests that X-ray PC techniques are very promising for evaluation of engineered tissues. In this review, four different implementations of X-ray PC imaging are described and applications to tissues of relevance to tissue engineering reviewed. In addition, recent applications of X-ray PC to the evaluation of biomaterial scaffolds and engineered tissues are presented and areas for further development and application of these techniques are discussed. Imaging techniques based on X-ray PC have significant potential for improving our ability to image and characterize engineered tissues, and their continued development and optimization could have significant impact on the field of tissue engineering. PMID:21682604

  9. Commercialising genetically engineered animal biomedical products.

    PubMed

    Sullivan, Eddie J; Pommer, Jerry; Robl, James M

    2008-01-01

    Research over the past two decades has increased the quality and quantity of tools available to produce genetically engineered animals. The number of potentially viable biomedical products from genetically engineered animals is increasing. However, moving from cutting-edge research to development and commercialisation of a biomedical product that is useful and wanted by the public has significant challenges. Even early stage development of genetically engineered animal applications requires consideration of many steps, including quality assurance and quality control, risk management, gap analysis, founder animal establishment, cell banking, sourcing of animals and animal-derived material, animal facilities, product collection facilities and processing facilities. These steps are complicated and expensive. Biomedical applications of genetically engineered animals have had some recent successes and many applications are well into development. As researchers consider applications for their findings, having a realistic understanding of the steps involved in the development and commercialisation of a product, produced in genetically engineered animals, is useful in determining the risk of genetic modification to the animal nu. the potential public benefit of the application.

  10. Functionalized carbon nanotubes for potential medicinal applications.

    PubMed

    Zhang, Yi; Bai, Yuhong; Yan, Bing

    2010-06-01

    Functionalized carbon nanotubes display unique properties that enable a variety of medicinal applications, including the diagnosis and treatment of cancer, infectious diseases and central nervous system disorders, and applications in tissue engineering. These potential applications are particularly encouraged by their ability to penetrate biological membranes and relatively low toxicity. High aspect ratio, unique optical property and the likeness as small molecule make carbon nanotubes an unusual allotrope of element carbon. After functionalization, carbon nanotubes display potentials for a variety of medicinal applications, including the diagnosis and treatment of cancer, infectious diseases and central nervous system disorders, and applications in tissue engineering. These potential applications are particularly encouraged by their ability to penetrate biological membranes and relatively low toxicity. (c) 2010 Elsevier Ltd. All rights reserved.

  11. Evaluation of advanced propulsion options for the next manned transportation system: Propulsion evolution study

    NASA Technical Reports Server (NTRS)

    Spears, L. T.; Kramer, R. D.

    1990-01-01

    The objectives were to examine launch vehicle applications and propulsion requirements for potential future manned space transportation systems and to support planning toward the evolution of Space Shuttle Main Engine (SSME) and Space Transportation Main Engine (STME) engines beyond their current or initial launch vehicle applications. As a basis for examinations of potential future manned launch vehicle applications, we used three classes of manned space transportation concepts currently under study: Space Transportation System Evolution, Personal Launch System (PLS), and Advanced Manned Launch System (AMLS). Tasks included studies of launch vehicle applications and requirements for hydrogen-oxygen rocket engines; the development of suggestions for STME engine evolution beyond the mid-1990's; the development of suggestions for STME evolution beyond the Advanced Launch System (ALS) application; the study of booster propulsion options, including LOX-Hydrocarbon options; the analysis of the prospects and requirements for utilization of a single engine configuration over the full range of vehicle applications, including manned vehicles plus ALS and Shuttle C; and a brief review of on-going and planned LOX-Hydrogen propulsion technology activities.

  12. Metal Matrix Composites for Rocket Engine Applications

    NASA Technical Reports Server (NTRS)

    McDonald, Kathleen R.; Wooten, John R.

    2000-01-01

    This document is from a presentation about the applications of Metal Matrix Composites (MMC) in rocket engines. Both NASA and the Air Force have goals which would reduce the costs and the weight of launching spacecraft. Charts show the engine weight distribution for both reuseable and expendable engine components. The presentation reviews the operating requirements for several components of the rocket engines. The next slide reviews the potential benefits of MMCs in general and in use as materials for Advanced Pressure Casting. The next slide reviews the drawbacks of MMCs. The reusable turbopump housing is selected to review for potential MMC application. The presentation reviews solutions for reusable turbopump materials, pointing out some of the issues. It also reviews the development of some of the materials.

  13. Handbook of data on selected engine components for solar thermal applications

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A data base on developed and commercially available power conversion system components for Rankine and Brayton cycle engines, which have potential application to solar thermal power-generating systems is presented. The status of the Stirling engine is discussed.

  14. Application of single crystal superalloys for Earth-to-orbit propulsion systems

    NASA Technical Reports Server (NTRS)

    Dreshfield, R. L.; Parr, R. A.

    1987-01-01

    Single crystal superalloys were first identified as potentially useful engineering materials for aircraft gas turbine engines in the mid-1960's. Although they were not introduced into service as turbine blades in commercial aircraft engines until the early 1980's, they have subsequently accumulated tens of millions of flight hours in revenue producing service. The space shuttle main engine (SSME) and potential advanced earth-to-orbit propulsion systems impose severe conditions on turbopump turbine blades which for some potential failure modes are more severe than in aircraft gas turbines. Research activities which are directed at evaluating the potential for single crystal superalloys for application as turbopump turbine blades in the SSME and advanced rocket engines are discussed. The mechanical properties of these alloys are summarized and the effects of hydrogen are noted. The use of high gradient directional solidification and hot isostatic pressing to improve fatigue properties is also addressed.

  15. Rocket engine numerical simulator

    NASA Technical Reports Server (NTRS)

    Davidian, Ken

    1993-01-01

    The topics are presented in viewgraph form and include the following: a rocket engine numerical simulator (RENS) definition; objectives; justification; approach; potential applications; potential users; RENS work flowchart; RENS prototype; and conclusion.

  16. Review of status and potential of tungsten-wire: Superalloy composites for advanced gas turbine engine blades

    NASA Technical Reports Server (NTRS)

    Signorelli, R. A.

    1972-01-01

    The current status of development of refractory-wire-superalloy composites and the potential for their application to turbine blades in land-based power generation and advanced aircraft engines are reviewed. The data indicate that refractory-wire-superalloy composites have application as turbine blades at temperatures of 2200 F and above.

  17. Rocket engine numerical simulation

    NASA Astrophysics Data System (ADS)

    Davidian, Ken

    1993-12-01

    The topics are presented in view graph form and include the following: a definition of the rocket engine numerical simulator (RENS); objectives; justification; approach; potential applications; potential users; RENS work flowchart; RENS prototype; and conclusions.

  18. Rocket engine numerical simulation

    NASA Technical Reports Server (NTRS)

    Davidian, Ken

    1993-01-01

    The topics are presented in view graph form and include the following: a definition of the rocket engine numerical simulator (RENS); objectives; justification; approach; potential applications; potential users; RENS work flowchart; RENS prototype; and conclusions.

  19. Status of the advanced Stirling conversion system project for 25 kW dish Stirling applications

    NASA Technical Reports Server (NTRS)

    Shaltens, Richard K.; Schreiber, Jeffrey G.

    1991-01-01

    Heat engines were evaluated for terrestrial Solar Distributed Heat Receivers. The Stirling engine was identified as one of the most promising heat engines for terrestrial applications. Technology development is also conducted for Stirling convertors directed toward a dynamic power source for space applications. Space power requirements include high reliability with very long life, low vibration, and high system efficiency. The free-piston Stirling engine has the potential for future high power space conversion systems, either nuclear or solar powered. Although both applications appear to be quite different, their requirements complement each other.

  20. Analysis of Wear Behavior of Graphene OXIDE — Polyamide Gears for Engineering Applications

    NASA Astrophysics Data System (ADS)

    Rajamani, Geetha; Paulraj, Jawahar; Krishnan, Kanny

    Recent advances in polymer nanocomposites open a wide range of applications in various industrial sectors. Due to their high potential properties, these materials are replacing the usage of metals for many heavier components in automobile industries. In this experimental work, the tribological performance of Graphene oxide (GO) — Polyamide is investigated against pristine polyamide by fabricating gears for the usage in engineering applications. A gear test rig was developed in-house for analysis to study the specific wear rate and temperature gradient at different conditions of load and speeds. The wear resistance of the polyamide gears with the addition of 0.03wt.% of graphene oxide is better than the pristine polyamide gears and the specific wear rate is reduced significantly. The reduced specific wear rate of these polymer nanocomposite gears is attributed to the superior properties of graphene oxide such as High specific surface area, good adhesion properties and enhanced glass transition temperatures. The GO nanocomposite gear seems to be a potential alternative against conventional gears for engineering applications. Finally, the wear mechanisms and the potential of GO-based polyamide nanocomposite gears were proposed tentatively in the development of transmission gears for engineering applications.

  1. High Temperature Solid Lubricant Materials for Heavy Duty and Advanced Heat Engines

    NASA Technical Reports Server (NTRS)

    Dellacorte, C.; Wood, J. C.

    1994-01-01

    Advanced engine designs incorporate higher mechanical and thermal loading to achieve efficiency improvements. This approach often leads to higher operating temperatures of critical sliding elements (e.g. piston ring/cylinder wall contacts and valve guides) which compromise the use of conventional and even advanced synthetic liquid lubricants. For these applications solid lubricants must be considered. Several novel solid lubricant composites and coatings designated PS/PM200 have been employed to dry and marginally oil lubricated contacts in advanced heat engines. These applications include cylinder kits of heavy duty diesels, and high temperature Stirling engines, sidewall seals of rotary engines, and various exhaust valve and exhaust component applications. This paper describes the tribological and thermophysical properties of these tribomaterials and reviews the results of applying them to engine applications. Other potential tribological materials and applications are also discussed with particular emphasis on heavy duty and advanced heat engines.

  2. Application of CFD codes to the design and development of propulsion systems

    NASA Technical Reports Server (NTRS)

    Lord, W. K.; Pickett, G. F.; Sturgess, G. J.; Weingold, H. D.

    1987-01-01

    The internal flows of aerospace propulsion engines have certain common features that are amenable to analysis through Computational Fluid Dynamics (CFD) computer codes. Although the application of CFD to engineering problems in engines was delayed by the complexities associated with internal flows, many codes with different capabilities are now being used as routine design tools. This is illustrated by examples taken from the aircraft gas turbine engine of flows calculated with potential flow, Euler flow, parabolized Navier-Stokes, and Navier-Stokes codes. Likely future directions of CFD applied to engine flows are described, and current barriers to continued progress are highlighted. The potential importance of the Numerical Aerodynamic Simulator (NAS) to resolution of these difficulties is suggested.

  3. Engineering Stem Cells for Biomedical Applications

    PubMed Central

    Yin, Perry T.; Han, Edward

    2018-01-01

    Stem cells are characterized by a number of useful properties, including their ability to migrate, differentiate, and secrete a variety of therapeutic molecules such as immunomodulatory factors. As such, numerous pre-clinical and clinical studies have utilized stem cell-based therapies and demonstrated their tremendous potential for the treatment of various human diseases and disorders. Recently, efforts have focused on engineering stem cells in order to further enhance their innate abilities as well as to confer them with new functionalities, which can then be used in various biomedical applications. These engineered stem cells can take on a number of forms. For instance, engineered stem cells encompass the genetic modification of stem cells as well as the use of stem cells for gene delivery, nanoparticle loading and delivery, and even small molecule drug delivery. The present Review gives an in-depth account of the current status of engineered stem cells, including potential cell sources, the most common methods used to engineer stem cells, and the utilization of engineered stem cells in various biomedical applications, with a particular focus on tissue regeneration, the treatment of immunodeficiency diseases, and cancer. PMID:25772134

  4. Composite material application for liquid rocket engines

    NASA Technical Reports Server (NTRS)

    Heubner, S. W.

    1982-01-01

    With increasing emphasis on improving engine thrust-to-weight ratios to provide improved payload capabilities, weight reductions achievable by the use of composites have become attractive. Of primary significance is the weight reduction offered by composites, although high temperature properties and cost reduction were also considered. The potential for application of composites to components of Earth-to-orbit hydrocarbon engines and orbit-to-orbit LOX/H2 engines was assessed. The components most likely to benefit from the application of composites were identified, as were the critical technology areas where developed would be required. Recommendations were made and a program outlined for the design, fabrication, and demonstration of specific engine components.

  5. Rational engineering of physicochemical properties of nanomaterials for biomedical applications with nanotoxicological perspectives.

    PubMed

    Navya, P N; Daima, Hemant Kumar

    2016-01-01

    Innovative engineered nanomaterials are at the leading edge of rapidly emerging fields of nanobiotechnology and nanomedicine. Meticulous synthesis, unique physicochemical properties, manifestation of chemical or biological moieties on the surface of materials make engineered nanostructures suitable for a variety of biomedical applications. Besides, tailored nanomaterials exhibit entirely novel therapeutic applications with better functionality, sensitivity, efficiency and specificity due to their customized unique physicochemical and surface properties. Additionally, such designer made nanomaterials has potential to generate series of interactions with various biological entities including DNA, proteins, membranes, cells and organelles at nano-bio interface. These nano-bio interactions are driven by colloidal forces and predominantly depend on the dynamic physicochemical and surface properties of nanomaterials. Nevertheless, recent development and atomic scale tailoring of various physical, chemical and surface properties of nanomaterials is promising to dictate their interaction in anticipated manner with biological entities for biomedical applications. As a result, rationally designed nanomaterials are in extensive demand for bio-molecular detection and diagnostics, therapeutics, drug and gene delivery, fluorescent labelling, tissue engineering, biochemical sensing and other pharmaceuticals applications. However, toxicity and risk associated with engineered nanomaterials is rather unclear or not well understood; which is gaining considerable attention and the field of nanotoxicology is evolving promptly. Therefore, this review explores current knowledge of articulate engineering of nanomaterials for biomedical applications with special attention on potential toxicological perspectives.

  6. Rational engineering of physicochemical properties of nanomaterials for biomedical applications with nanotoxicological perspectives

    NASA Astrophysics Data System (ADS)

    Navya, P. N.; Daima, Hemant Kumar

    2016-02-01

    Innovative engineered nanomaterials are at the leading edge of rapidly emerging fields of nanobiotechnology and nanomedicine. Meticulous synthesis, unique physicochemical properties, manifestation of chemical or biological moieties on the surface of materials make engineered nanostructures suitable for a variety of biomedical applications. Besides, tailored nanomaterials exhibit entirely novel therapeutic applications with better functionality, sensitivity, efficiency and specificity due to their customized unique physicochemical and surface properties. Additionally, such designer made nanomaterials has potential to generate series of interactions with various biological entities including DNA, proteins, membranes, cells and organelles at nano-bio interface. These nano-bio interactions are driven by colloidal forces and predominantly depend on the dynamic physicochemical and surface properties of nanomaterials. Nevertheless, recent development and atomic scale tailoring of various physical, chemical and surface properties of nanomaterials is promising to dictate their interaction in anticipated manner with biological entities for biomedical applications. As a result, rationally designed nanomaterials are in extensive demand for bio-molecular detection and diagnostics, therapeutics, drug and gene delivery, fluorescent labelling, tissue engineering, biochemical sensing and other pharmaceuticals applications. However, toxicity and risk associated with engineered nanomaterials is rather unclear or not well understood; which is gaining considerable attention and the field of nanotoxicology is evolving promptly. Therefore, this review explores current knowledge of articulate engineering of nanomaterials for biomedical applications with special attention on potential toxicological perspectives.

  7. Preliminary designs for 25 kWe advanced Stirling conversion systems for dish electric applications

    NASA Technical Reports Server (NTRS)

    Shaltens, Richard K.; Schreiber, Jeffrey G.

    1990-01-01

    Under the Department of Energy's (DOE) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for terrestrial Solar Distributed Heat Receivers. The Stirling engine has been identified by Sandia as one of the most promising engines for terrestrial applications. The Stirling engine also has the potential to meet DOE's performance and cost goals. The NASA Lewis Research Center is conducting Stirling engine technology development activities directed toward a dynamic power source for space applications. Space power systems requirements include high reliability, very long life, low vibration and high efficiency. The free-piston Stirling engine has the potential for future high power space conversion systems, either nuclear or solar powered. Although both applications appear to be quite different, their requirements complement each other. Preliminary designs feature a free-piston Stirling engine, a liquid metal heat transport system, and a means to provide nominally 25 kW electric power to a utility grid while meeting DOE's performance and long term cost goals. The Cummins design incorporates a linear alternator to provide the electrical output, while the STC design generates electrical power indirectly through a hydraulic pump/motor coupled to an induction generator. Both designs for the ASCS's will use technology which can reasonably be expected to be available in the early 1990's.

  8. Preliminary designs for 25 kWe advanced Stirling conversion systems for dish electric applications

    NASA Astrophysics Data System (ADS)

    Shaltens, Richard K.; Schreiber, Jeffrey G.

    Under the Department of Energy's (DOE) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for terrestrial Solar Distributed Heat Receivers. The Stirling engine has been identified by Sandia as one of the most promising engines for terrestrial applications. The Stirling engine also has the potential to meet DOE's performance and cost goals. The NASA Lewis Research Center is conducting Stirling engine technology development activities directed toward a dynamic power source for space applications. Space power systems requirements include high reliability, very long life, low vibration and high efficiency. The free-piston Stirling engine has the potential for future high power space conversion systems, either nuclear or solar powered. Although both applications appear to be quite different, their requirements complement each other. Preliminary designs feature a free-piston Stirling engine, a liquid metal heat transport system, and a means to provide nominally 25 kW electric power to a utility grid while meeting DOE's performance and long term cost goals. The Cummins design incorporates a linear alternator to provide the electrical output, while the STC design generates electrical power indirectly through a hydraulic pump/motor coupled to an induction generator. Both designs for the ASCS's will use technology which can reasonably be expected to be available in the early 1990's.

  9. Preliminary designs for 25 kWe advanced Stirling conversion systems for dish electric applications

    NASA Technical Reports Server (NTRS)

    Shaltens, Richard K.; Schreiber, Jeffrey G.

    1990-01-01

    Under the Department of Energy's (DOE) Solar Thermal Technology Program, Sandia National Laboratories is evaluating heat engines for terrestrial Solar Distributed Heat Receivers. The Stirling engine has been identified by Sandia as one of the most promising engines for terrestrial applications. The Stirling engine also has the potential to meet DOE's performance and cost goals. The NASA Lewis Research Center is conducting Stirling engine technology development activities directed toward a dynamic power source for space applications. Space power systems requirements include high reliability, very long life, low vibration and high efficiency. The free-piston Stirling engine has the potential for future high power space conversion systems, either nuclear or solar powered. Although both applications appear to be quite different, their requirements complement each other. Preliminary designs feature a free-piston Stirling engine, a liquid metal heat transport system, and a means to provide nominally 25 kW electric power to a utility grid while meeting DOE's performance and long term cost goals. The Cummins design incorporates a linear alternator to provide the electrical output, while the STC design generates electrical power indirectly through a hydraulic pump/motor coupled to an induction generator. Both designs for the ASCS's will use technology which can reasonably be expected to be available in the early 1990's

  10. Eutectic Composite Turbine Blade Development

    DTIC Science & Technology

    1976-11-01

    turbine blades for aircraft engines . An MC carbide fiber reinforced eutectic alloy, NiTaC-13...composites in turbine blades for aircraft engines . An MC carbide fiber reinforced eutectic alloy, NiTaC-13 and the low pressure turbine blade of the...identified that appeared to have potential for application to aircraft engine turbine blade hardware. The potential benefits offered by these materials

  11. The application of GMOs in agriculture and in food production for a better nutrition: two different scientific points of view.

    PubMed

    Buiatti, M; Christou, P; Pastore, G

    2013-05-01

    This commentary is a face-to-face debate between two almost opposite positions regarding the application of genetic engineering in agriculture and food production. Seven questions on the potential benefits of the application of genetic engineering in agriculture and on the potentially adverse impacts on the environment and human health were posed to two scientists: one who is sceptical about the use of GMOs in Agriculture, and one who views GMOs as an important tool for quantitatively and qualitatively improving food production.

  12. Study of small civil turbofan engines applicable to military trainer airplanes

    NASA Technical Reports Server (NTRS)

    Heldenbrand, R. W.; Merrill, G. L.; Burnett, G. A.

    1975-01-01

    Small turbofan engine design concepts were applied to military trainer airplanes to establish the potential for commonality between civil and military engines. Several trainer configurations were defined and studied. A ""best'' engine was defined for the trainer mission, and sensitivity analyses were performed to determine the effects on airplane size and efficiency of wing loading, power loading, configuration, aerodynamic quality, and engine quality. It is concluded that a small civil aircraft is applicable to military trainer airplanes. Aircraft designed with these engines are smaller, less costly, and more efficient than existing trainer aircraft.

  13. The potential of tissue engineering for developing alternatives to animal experiments: a systematic review.

    PubMed

    de Vries, Rob B M; Leenaars, Marlies; Tra, Joppe; Huijbregtse, Robbertjan; Bongers, Erik; Jansen, John A; Gordijn, Bert; Ritskes-Hoitinga, Merel

    2015-07-01

    An underexposed ethical issue raised by tissue engineering is the use of laboratory animals in tissue engineering research. Even though this research results in suffering and loss of life in animals, tissue engineering also has great potential for the development of alternatives to animal experiments. With the objective of promoting a joint effort of tissue engineers and alternative experts to fully realise this potential, this study provides the first comprehensive overview of the possibilities of using tissue-engineered constructs as a replacement of laboratory animals. Through searches in two large biomedical databases (PubMed, Embase) and several specialised 3R databases, 244 relevant primary scientific articles, published between 1991 and 2011, were identified. By far most articles reviewed related to the use of tissue-engineered skin/epidermis for toxicological applications such as testing for skin irritation. This review article demonstrates, however, that the potential for the development of alternatives also extends to other tissues such as other epithelia and the liver, as well as to other fields of application such as drug screening and basic physiology. This review discusses which impediments need to be overcome to maximise the contributions that the field of tissue engineering can make, through the development of alternative methods, to the reduction of the use and suffering of laboratory animals. Copyright © 2013 John Wiley & Sons, Ltd.

  14. Engineering Stem Cells for Biomedical Applications.

    PubMed

    Yin, Perry T; Han, Edward; Lee, Ki-Bum

    2016-01-07

    Stem cells are characterized by a number of useful properties, including their ability to migrate, differentiate, and secrete a variety of therapeutic molecules such as immunomodulatory factors. As such, numerous pre-clinical and clinical studies have utilized stem cell-based therapies and demonstrated their tremendous potential for the treatment of various human diseases and disorders. Recently, efforts have focused on engineering stem cells in order to further enhance their innate abilities as well as to confer them with new functionalities, which can then be used in various biomedical applications. These engineered stem cells can take on a number of forms. For instance, engineered stem cells encompass the genetic modification of stem cells as well as the use of stem cells for gene delivery, nanoparticle loading and delivery, and even small molecule drug delivery. The present Review gives an in-depth account of the current status of engineered stem cells, including potential cell sources, the most common methods used to engineer stem cells, and the utilization of engineered stem cells in various biomedical applications, with a particular focus on tissue regeneration, the treatment of immunodeficiency diseases, and cancer. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Solid Free-form Fabrication Technology and Its Application to Bone Tissue Engineering

    PubMed Central

    Lee, Jin Woo; Kim, Jong Young; Cho, Dong-Woo

    2010-01-01

    The development of scaffolds for use in cell-based therapies to repair damaged bone tissue has become a critical component in the field of bone tissue engineering. However, design of scaffolds using conventional fabrication techniques has limited further advancement, due to a lack of the required precision and reproducibility. To overcome these constraints, bone tissue engineers have focused on solid free-form fabrication (SFF) techniques to generate porous, fully interconnected scaffolds for bone tissue engineering applications. This paper reviews the potential application of SFF fabrication technologies for bone tissue engineering with respect to scaffold fabrication. In the near future, bone scaffolds made using SFF apparatus should become effective therapies for bone defects. PMID:24855546

  16. Applications

    NASA Astrophysics Data System (ADS)

    Stern, Arthur M.

    1986-07-01

    Economic incentives have spurred numerous applications of genetically engineered organisms in manufacture of pharmaceuticals and industrial chemicals. These successes, involving a variety of methods of genetic manipulation, have dispelled early fears that genetic engineering could not be handled safely, even in the laboratory. Consequently, the potential for applications in the wider environment without physical containment is being considered for agriculture, mining, pollution control, and pest control. These proposed applications range from modest extensions of current plant breeding techniques for new disease-resistant species to radical combinations of organisms (for example, nitrogen-fixing corn plants). These applications raise concerns about potential ecological impacts (see chapter 5), largely because of adverse experiences with both deliberate and inadvertent introductions of nonindigenous species.

  17. DOT/NASA comparative assessment of Brayton engines for guideway vehicles and busses. Volume 2: Analysis and results

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Gas turbine engines were assessed for application to hear duty transportation. A summary of the assumptions, applications, and methods of analysis is included along with a discussion of the approach taken, the technical program flow chart, and weighting criteria used for performance evaluation. The various engines are compared on the bases of weight, performance, emissions and noise, technology status, and growth potential. The results of the engine screening phase and the conceptual design phase are presented.

  18. Building information modelling review with potential applications in tunnel engineering of China.

    PubMed

    Zhou, Weihong; Qin, Haiyang; Qiu, Junling; Fan, Haobo; Lai, Jinxing; Wang, Ke; Wang, Lixin

    2017-08-01

    Building information modelling (BIM) can be applied to tunnel engineering to address a number of problems, including complex structure, extensive design, long construction cycle and increased security risks. To promote the development of tunnel engineering in China, this paper combines actual cases, including the Xingu mountain tunnel and the Shigu Mountain tunnel, to systematically analyse BIM applications in tunnel engineering in China. The results indicate that BIM technology in tunnel engineering is currently mainly applied during the design stage rather than during construction and operation stages. The application of BIM technology in tunnel engineering covers many problems, such as a lack of standards, incompatibility of different software, disorganized management, complex combination with GIS (Geographic Information System), low utilization rate and poor awareness. In this study, through summary of related research results and engineering cases, suggestions are introduced and an outlook for the BIM application in tunnel engineering in China is presented, which provides guidance for design optimization, construction standards and later operation maintenance.

  19. Building information modelling review with potential applications in tunnel engineering of China

    PubMed Central

    Zhou, Weihong; Qin, Haiyang; Fan, Haobo; Lai, Jinxing; Wang, Ke; Wang, Lixin

    2017-01-01

    Building information modelling (BIM) can be applied to tunnel engineering to address a number of problems, including complex structure, extensive design, long construction cycle and increased security risks. To promote the development of tunnel engineering in China, this paper combines actual cases, including the Xingu mountain tunnel and the Shigu Mountain tunnel, to systematically analyse BIM applications in tunnel engineering in China. The results indicate that BIM technology in tunnel engineering is currently mainly applied during the design stage rather than during construction and operation stages. The application of BIM technology in tunnel engineering covers many problems, such as a lack of standards, incompatibility of different software, disorganized management, complex combination with GIS (Geographic Information System), low utilization rate and poor awareness. In this study, through summary of related research results and engineering cases, suggestions are introduced and an outlook for the BIM application in tunnel engineering in China is presented, which provides guidance for design optimization, construction standards and later operation maintenance. PMID:28878970

  20. Building information modelling review with potential applications in tunnel engineering of China

    NASA Astrophysics Data System (ADS)

    Zhou, Weihong; Qin, Haiyang; Qiu, Junling; Fan, Haobo; Lai, Jinxing; Wang, Ke; Wang, Lixin

    2017-08-01

    Building information modelling (BIM) can be applied to tunnel engineering to address a number of problems, including complex structure, extensive design, long construction cycle and increased security risks. To promote the development of tunnel engineering in China, this paper combines actual cases, including the Xingu mountain tunnel and the Shigu Mountain tunnel, to systematically analyse BIM applications in tunnel engineering in China. The results indicate that BIM technology in tunnel engineering is currently mainly applied during the design stage rather than during construction and operation stages. The application of BIM technology in tunnel engineering covers many problems, such as a lack of standards, incompatibility of different software, disorganized management, complex combination with GIS (Geographic Information System), low utilization rate and poor awareness. In this study, through summary of related research results and engineering cases, suggestions are introduced and an outlook for the BIM application in tunnel engineering in China is presented, which provides guidance for design optimization, construction standards and later operation maintenance.

  1. Paraffin-based hybrid rocket engines applications: A review and a market perspective

    NASA Astrophysics Data System (ADS)

    Mazzetti, Alessandro; Merotto, Laura; Pinarello, Giordano

    2016-09-01

    Hybrid propulsion technology for aerospace applications has received growing attention in recent years due to its important advantages over competitive solutions. Hybrid rocket engines have a great potential for several aeronautics and aerospace applications because of their safety, reliability, low cost and high performance. As a consequence, this propulsion technology is feasible for a number of innovative missions, including space tourism. On the other hand, hybrid rocket propulsion's main drawback, i.e. the difficulty in reaching high regression rate values using standard fuels, has so far limited the maturity level of this technology. The complex physico-chemical processes involved in hybrid rocket engines combustion are of major importance for engine performance prediction and control. Therefore, further investigation is ongoing in order to achieve a more complete understanding of such phenomena. It is well known that one of the most promising solutions for overcoming hybrid rocket engines performance limits is the use of liquefying fuels. Such fuels can lead to notably increased solid fuel regression rate due to the so-called "entrainment phenomenon". Among liquefying fuels, paraffin-based formulations have great potentials as solid fuels due to their low cost, availability (as they can be derived from industrial waste), low environmental impact and high performance. Despite the vast amount of literature available on this subject, a precise focus on market potential of paraffins for hybrid propulsion aerospace applications is lacking. In this work a review of hybrid rocket engines state of the art was performed, together with a detailed analysis of the possible applications of such a technology. A market study was carried out in order to define the near-future foreseeable development needs for hybrid technology application to the aforementioned missions. Paraffin-based fuels are taken into account as the most promising segment for market development.The present study is useful for driving future investigation and testing of paraffin-based fuels as solid fuels for hybrid propulsion technology, taking into account the needs of industrial applications of this technology.

  2. Numerical methods for engine-airframe integration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Murthy, S.N.B.; Paynter, G.C.

    1986-01-01

    Various papers on numerical methods for engine-airframe integration are presented. The individual topics considered include: scientific computing environment for the 1980s, overview of prediction of complex turbulent flows, numerical solutions of the compressible Navier-Stokes equations, elements of computational engine/airframe integrations, computational requirements for efficient engine installation, application of CAE and CFD techniques to complete tactical missile design, CFD applications to engine/airframe integration, and application of a second-generation low-order panel methods to powerplant installation studies. Also addressed are: three-dimensional flow analysis of turboprop inlet and nacelle configurations, application of computational methods to the design of large turbofan engine nacelles, comparison ofmore » full potential and Euler solution algorithms for aeropropulsive flow field computations, subsonic/transonic, supersonic nozzle flows and nozzle integration, subsonic/transonic prediction capabilities for nozzle/afterbody configurations, three-dimensional viscous design methodology of supersonic inlet systems for advanced technology aircraft, and a user's technology assessment.« less

  3. Space shuttle main engine computed tomography applications

    NASA Technical Reports Server (NTRS)

    Sporny, Richard F.

    1990-01-01

    For the past two years the potential applications of computed tomography to the fabrication and overhaul of the Space Shuttle Main Engine were evaluated. Application tests were performed at various government and manufacturer facilities with equipment produced by four different manufacturers. The hardware scanned varied in size and complexity from a small temperature sensor and turbine blades to an assembled heat exchanger and main injector oxidizer inlet manifold. The evaluation of capabilities included the ability to identify and locate internal flaws, measure the depth of surface cracks, measure wall thickness, compare manifold design contours to actual part contours, perform automatic dimensional inspections, generate 3D computer models of actual parts, and image the relationship of the details in a complex assembly. The capabilities evaluated, with the exception of measuring the depth of surface flaws, demonstrated the existing and potential ability to perform many beneficial Space Shuttle Main Engine applications.

  4. Metallic ions as therapeutic agents in tissue engineering scaffolds: an overview of their biological applications and strategies for new developments

    PubMed Central

    Mouriño, Viviana; Cattalini, Juan Pablo; Boccaccini, Aldo R.

    2012-01-01

    This article provides an overview on the application of metallic ions in the fields of regenerative medicine and tissue engineering, focusing on their therapeutic applications and the need to design strategies for controlling the release of loaded ions from biomaterial scaffolds. A detailed summary of relevant metallic ions with potential use in tissue engineering approaches is presented. Remaining challenges in the field and directions for future research efforts with focus on the key variables needed to be taken into account when considering the controlled release of metallic ions in tissue engineering therapeutics are also highlighted. PMID:22158843

  5. Application of a data base management system to a finite element model

    NASA Technical Reports Server (NTRS)

    Rogers, J. L., Jr.

    1980-01-01

    In today's software market, much effort is being expended on the development of data base management systems (DBMS). Most commercially available DBMS were designed for business use. However, the need for such systems within the engineering and scientific communities is becoming apparent. A potential DBMS application that appears attractive is the handling of data for finite element engineering models. The applications of a commercially available, business-oriented DBMS to a structural engineering, finite element model is explored. The model, DBMS, an approach to using the DBMS, advantages and disadvantages are described. Plans for research on a scientific and engineering DBMS are discussed.

  6. Fiberoptic sensors for rocket engine applications

    NASA Technical Reports Server (NTRS)

    Ballard, R. O.

    1992-01-01

    A research effort was completed to summarize and evaluate the current level of technology in fiberoptic sensors for possible applications in integrated control and health monitoring (ICHM) systems in liquid propellant engines. The environment within a rocket engine is particuarly severe with very high temperatures and pressures present combined with extremely rapid fluid and gas flows, and high-velocity and high-intensity acoustc waves. Application of fiberoptic technology to rocket engine health monitoring is a logical evolutionary step in ICHM development and presents a significant challenge. In this extremely harsh environment, the additional flexibility of fiberoptic techniques to augment conventional sensor technologies offer abundant future potential.

  7. Small-scale heat detection using catalytic microengines irradiated by laser

    NASA Astrophysics Data System (ADS)

    Liu, Zhaoqian; Li, Jinxing; Wang, Jiao; Huang, Gaoshan; Liu, Ran; Mei, Yongfeng

    2013-01-01

    We demonstrate a novel approach to modulating the motion speed of catalytic microtubular engines via laser irradiation/heating with regard to small-scale heat detection. Laser irradiation on the engines leads to a thermal heating effect and thus enhances the engine speed. During a laser on/off period, the motion behaviour of a microengine can be repeatable and reversible, demonstrating a regulation of motion speeds triggered by laser illumination. Also, the engine velocity exhibits a linear dependence on laser power in various fuel concentrations, which implies an application potential as local heat sensors. Our work may hold great promise in applications such as lab on a chip, micro/nano factories, and environmental detection.We demonstrate a novel approach to modulating the motion speed of catalytic microtubular engines via laser irradiation/heating with regard to small-scale heat detection. Laser irradiation on the engines leads to a thermal heating effect and thus enhances the engine speed. During a laser on/off period, the motion behaviour of a microengine can be repeatable and reversible, demonstrating a regulation of motion speeds triggered by laser illumination. Also, the engine velocity exhibits a linear dependence on laser power in various fuel concentrations, which implies an application potential as local heat sensors. Our work may hold great promise in applications such as lab on a chip, micro/nano factories, and environmental detection. Electronic supplementary information (ESI) available. See DOI: 10.1039/c2nr32494f

  8. Textile Technologies and Tissue Engineering: A Path Towards Organ Weaving

    PubMed Central

    Akbari, Mohsen; Tamayol, Ali; Bagherifard, Sara; Serex, Ludovic; Mostafalu, Pooria; Faramarzi, Negar; Mohammadi, Mohammad Hossein

    2016-01-01

    Textile technologies have recently attracted great attention as potential biofabrication tools for engineering tissue constructs. Using current textile technologies, fibrous structures can be designed and engineered to attain the required properties that are demanded by different tissue engineering applications. Several key parameters such as physiochemical characteristics of fibers, pore size and mechanical properties of the fabrics play important role in the effective use of textile technologies in tissue engineering. This review summarizes the current advances in the manufacturing of biofunctional fibers. Different textile methods such as knitting, weaving, and braiding are discussed and their current applications in tissue engineering are highlighted. PMID:26924450

  9. Engineering three-dimensional cardiac microtissues for potential drug screening applications.

    PubMed

    Wang, L; Huang, G; Sha, B; Wang, S; Han, Y L; Wu, J; Li, Y; Du, Y; Lu, T J; Xu, F

    2014-01-01

    Heart disease is one of the major global health issues. Despite rapid advances in cardiac tissue engineering, limited successful strategies have been achieved to cure cardiovascular diseases. This situation is mainly due to poor understanding of the mechanism of diverse heart diseases and unavailability of effective in vitro heart tissue models for cardiovascular drug screening. With the development of microengineering technologies, three-dimensional (3D) cardiac microtissue (CMT) models, mimicking 3D architectural microenvironment of native heart tissues, have been developed. The engineered 3D CMT models hold greater potential to be used for assessing effective drugs candidates than traditional two-dimensional cardiomyocyte culture models. This review discusses the development of 3D CMT models and highlights their potential applications for high-throughput screening of cardiovascular drug candidates.

  10. Small Engine Component Technology (SECT) study. Program report

    NASA Technical Reports Server (NTRS)

    Almodovar, E.; Exley, T.; Kaehler, H.; Schneider, W.

    1986-01-01

    The study was conducted to identify high payoff technologies for year 2000 small gas turbine applications and to provide a technology plan for guiding future research and technology efforts. A regenerative cycle turboprop engine was selected for a 19 passenger commuter aircraft application. A series of engines incorporating eight levels of advanced technologies were studied and their impact on aircraft performance was evaluated. The study indicated a potential reduction in fuel burn of 38.3 percent. At $1.00 per gallon fuel price, a potential DOC benefit of 12.5 percent would be achieved. At $2.00 per gallon, the potential DOC benefit would increase to 17.0 percent. Four advanced technologies are recommended and appropriate research and technology programs were established to reach the year 2000 goals.

  11. Manufacturing Techniques for Application of Erosion Resistant Coatings to Turbine Engine Compressor Components.

    DTIC Science & Technology

    means of increasing the life of aircraft gas turbine compressor rotor blades and stator vanes . Two proprietary erosion resistant coating systems... engine tests as the two most promising systems for doubling compressor airfoil lives. An Air Force Sponsored program to evaluate the applicability of...Helicopter engine erosion has become a severe problem in S. E. Asia because of extensive operations in sand and dust. Hard coatings offer a potential

  12. Potential of plant proteins for medical applications.

    PubMed

    Reddy, Narendra; Yang, Yiqi

    2011-10-01

    Various natural and synthetic polymers are being explored to develop biomaterials for tissue engineering and drug delivery. Although proteins are preferable over carbohydrates and synthetic polymers, biomaterials developed from proteins lack the mechanical properties and/or biocompatibilities required for medical applications. Plant proteins are widely available, have low potential to be immunogenic and can be made into fibers, films, hydrogels and micro- and nano-particles for medical applications. Studies, mostly with zein, have demonstrated the potential of using plant proteins for tissue engineering and drug delivery. Although other plant proteins such as wheat gluten and soyproteins have also shown biocompatibility using in vitro studies, fabricating biomaterials such as nano-fibers and nano-particles from soy and wheat proteins offers considerable challenges. Copyright © 2011. Published by Elsevier Ltd.

  13. Aircraft engine pollution reduction

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1972-01-01

    The effect of engine operation on the types and levels of the major aircraft engine pollutants is described and the major factors governing the formation of these pollutants during the burning of hydrocarbon fuel are discussed. Methods which are being explored to reduce these pollutants are discussed and their application to several experimental research programs are pointed out. Results showing significant reductions in the levels of carbon monoxide, unburned hydrocarbons, and oxides of nitrogen obtained from experimental combustion research programs are presented and discussed to point out potential application to aircraft engines.

  14. Human embryonic stem cell-derived mesodermal progenitors display substantially increased tissue formation compared to human mesenchymal stem cells under dynamic culture conditions in a packed bed/column bioreactor.

    PubMed

    de Peppo, Giuseppe Maria; Sladkova, Martina; Sjövall, Peter; Palmquist, Anders; Oudina, Karim; Hyllner, Johan; Thomsen, Peter; Petite, Hervé; Karlsson, Camilla

    2013-01-01

    Bone tissue engineering represents a promising strategy to obviate bone deficiencies, allowing the ex vivo construction of bone substitutes with unprecedented potential in the clinical practice. Considering that in the human body cells are constantly stimulated by chemical and mechanical stimuli, the use of bioreactor is emerging as an essential factor for providing the proper environment for the reproducible and large-scale production of the engineered substitutes. Human mesenchymal stem cells (hMSCs) are experimentally relevant cells but, regardless the encouraging results reported after culture under dynamic conditions in bioreactors, show important limitations for tissue engineering applications, especially considering their limited proliferative potential, loss of functionality following protracted expansion, and decline in cellular fitness associated with aging. On the other hand, we previously demonstrated that human embryonic stem cell-derived mesodermal progenitors (hES-MPs) hold great potential to provide a homogenous and unlimited source of cells for bone engineering applications. Based on prior scientific evidence using different types of stem cells, in the present study we hypothesized that dynamic culture of hES-MPs in a packed bed/column bioreactor had the potential to affect proliferation, expression of genes involved in osteogenic differentiation, and matrix mineralization, therefore resulting in increased bone-like tissue formation. The reported findings suggest that hES-MPs constitute a suitable alternative cell source to hMSCs and hold great potential for the construction of bone substitutes for tissue engineering applications in clinical settings.

  15. Human iPSC-derived cardiomyocytes and tissue engineering strategies for disease modeling and drug screening

    PubMed Central

    Smith, Alec S.T.; Macadangdang, Jesse; Leung, Winnie; Laflamme, Michael A.; Kim, Deok-Ho

    2016-01-01

    Improved methodologies for modeling cardiac disease phenotypes and accurately screening the efficacy and toxicity of potential therapeutic compounds are actively being sought to advance drug development and improve disease modeling capabilities. To that end, much recent effort has been devoted to the development of novel engineered biomimetic cardiac tissue platforms that accurately recapitulate the structure and function of the human myocardium. Within the field of cardiac engineering, induced pluripotent stem cells (iPSCs) are an exciting tool that offer the potential to advance the current state of the art, as they are derived from somatic cells, enabling the development of personalized medical strategies and patient specific disease models. Here we review different aspects of iPSC-based cardiac engineering technologies. We highlight methods for producing iPSC-derived cardiomyocytes (iPSC-CMs) and discuss their application to compound efficacy/toxicity screening and in vitro modeling of prevalent cardiac diseases. Special attention is paid to the application of micro- and nano-engineering techniques for the development of novel iPSC-CM based platforms and their potential to advance current preclinical screening modalities. PMID:28007615

  16. Magnetic targeting of mechanosensors in bone cells for tissue engineering applications.

    PubMed

    Hughes, Steven; Dobson, Jon; El Haj, Alicia J

    2007-01-01

    Mechanical signalling plays a pivotal role in maintaining bone cell function and remodelling of the skeleton. Our previous work has highlighted the potential role of mechano-induction in tissue engineering applications. In particular, we have highlighted the potential for using magnetic particle techniques for tissue engineering applications. Previous studies have shown that manipulation of integrin attached magnetic particles leads to changes in intracellular calcium signalling within osteoblasts. However, due to the phenomenon of particle internalisation, previous studies have typically focused on short-term stimulation experiments performed within 1-2 h of particle attachment. For tissue engineering applications, bone tissue growth occurs over a period of 3-5 weeks. To date, no study has investigated the cellular responses elicited from osteoblasts over time following stimulation with internalised magnetic particles. Here, we demonstrate the long-term biocompatibility of 4.5 microm RGD-coated particles with osteoblasts up to 21 days in culture, and detail a time course of responses elicited from osteoblasts following mechanical stimulation with integrin attached magnetic particles (<2h post attachment) and internalised particles (>48h post attachment). Mechanical manipulation of both integrin attached and internalised particles were found to induce intracellular calcium signalling. It is concluded that magnetic particles offer a tool for applying controlled mechanical forces to osteoblasts, and can be used to stimulate intracellular calcium signalling over prolonged periods of time. Magnetic particle technology presents a potentially valuable tool for tissue engineering which permits the delivery of highly localised mechano-inductive forces directly to cells.

  17. Structure-based Engineering of a Plant-Fungal Hybrid Peroxidase for Enhanced Temperature and pH Tolerance.

    PubMed

    Kohler, Amanda C; Simmons, Blake A; Sale, Kenneth L

    2018-04-28

    In an age of ever-increasing biotechnological and industrial demand for new and specialized biocatalysts, rational protein engineering offers a direct approach to enzyme design and innovation. Heme peroxidases, as indispensable oxidative biocatalysts, provide a relatively mild alternative to the traditional harsh, and often toxic, chemical catalysts, and subsequently, have found widespread application throughout industry. However, the potential for these enzymes is far greater than their present use, as processes are currently restricted to the more stable, but less catalytically powerful, subset of peroxidases. Here we describe the structure-guided, rational engineering of a plant-fungal hybrid peroxidase built to overcome the application barrier of these high-reduction potential peroxidases. This engineered enzyme has the catalytic versatility and oxidative ability of a high-reduction potential versatile peroxidase, with enhanced temperature and pH tolerance similar to that of a highly stable plant peroxidase. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. Intermetallic and ceramic matrix composites for 815 to 1370 C (1500 to 2500 F) gas turbine engine applications

    NASA Technical Reports Server (NTRS)

    Stephens, Joseph R.

    1989-01-01

    Light weight and potential high temperature capability of intermetallic compounds, such as the aluminides, and structural ceramics, such as the carbides and nitrides, make these materials attractive for gas turbine engine applications. In terms of specific fuel consumption and specific thrust, revolutionary improvements over current technology are being sought by realizing the potential of these materials through their use as matrices combined with high strength, high temperature fibers. The U.S. along with other countries throughout the world have major research and development programs underway to characterize these composites materials; improve their reliability; identify and develop new processing techniques, new matrix compositions, and new fiber compositions; and to predict their life and failure mechanisms under engine operating conditions. The status is summarized of NASA's Advanced High Temperature Engine Materials Technology Program (HITEMP) and the potential benefits are described to be gained in 21st century transport aircraft by utilizing intermetallic and ceramic matrix composite materials.

  19. Contingency Power Study for Short Haul Civil Tiltrotor

    NASA Technical Reports Server (NTRS)

    D'Angelo, Marin M.

    2004-01-01

    NASA has concluded from previous studies that the twin engine tiltrotor is the most economical and technologically viable rotorcraft for near-term civil applications. Twin engine civil rotorcraft must be able to hover safely on one engine in an emergency. This emergency power requirement generally results in engines 20 to 50 percent larger than needed for normal engine operation, negatively impacting aircraft economics. This study identifies several contingency power enhancement concepts, and quantifies their potential to reduce aircraft operating costs. Many unique concepts were examined, and the selected concepts are simple, reliable, and have a high potential for near term realization. These engine concepts allow extremely high turbine temperatures during emergency operation by providing cooling to the power turbine and augmenting cooling of both turbines and structural hardware. Direct operating cost are reduced 3 to percent, which could yield a 30 to 80 percent increase in operating profits. The study consists of the definition of an aircraft economics model and a baseline engine, and an engine concept screening study, and a preliminary definition of the selected concepts. The selected concepts are evaluated against the baseline engine, and the critical technologies and development needs are identified, along with applications for this technology.

  20. Cardiovascular tissue engineering: where we come from and where are we now?

    PubMed

    Smit, Francis E; Dohmen, Pascal M

    2015-01-27

    Abstract Tissue engineering was introduced by Vacanti and Langer in the 80's, exploring the potential of this new technology starting with the well-known "human ear on the mouse back". The goal is to create a substitute which supplies an individual therapy for patients with regeneration, remodeling and growth potential. The growth potential of these subjects is of special interest in congenital cardiac surgery, avoiding repeated interventions and surgery. Initial applications of tissue engineered created substitutes were relatively simple cardiovascular grafts seeded initially by end-differentiated autologous endothelial cells. Important data were collected from these initial clinical autologous endothelial cell seeded grafts in peripheral and coronary vessel disease. After these initial successfully implantation bone marrow cell were used to seed patches and pulmonary conduits were implanted in patients. Driven by the positive results of tissue engineered material implanted under low pressure circumstances, first tissue engineered patches were implanted in the systemic circulation followed by the implantation of tissue engineered aortic heart valves. Tissue engineering is an extreme dynamic technology with continuously modifications and improvements to optimize clinical products. New technologies are unified and so this has also be done with tissue engineering and new application features, so called transcatheter valve intervention. First studies are initiated to apply tissue engineered heart valves with this new transcatheter delivery system less invasive. Simultaneously studies have been started on tissue engineering of so-called whole organs since organ transplantation is restricted due to donor shortage and tissue engineering could overcome this problem. Initial studies of whole heart engineering in the rat model are promising and larger size models are initiated.

  1. Textile Technologies and Tissue Engineering: A Path Toward Organ Weaving.

    PubMed

    Akbari, Mohsen; Tamayol, Ali; Bagherifard, Sara; Serex, Ludovic; Mostafalu, Pooria; Faramarzi, Negar; Mohammadi, Mohammad Hossein; Khademhosseini, Ali

    2016-04-06

    Textile technologies have recently attracted great attention as potential biofabrication tools for engineering tissue constructs. Using current textile technologies, fibrous structures can be designed and engineered to attain the required properties that are demanded by different tissue engineering applications. Several key parameters such as physiochemical characteristics of fibers, microarchitecture, and mechanical properties of the fabrics play important roles in the effective use of textile technologies in tissue engineering. This review summarizes the current advances in the manufacturing of biofunctional fibers. Different textile methods such as knitting, weaving, and braiding are discussed and their current applications in tissue engineering are highlighted. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Delivery of small molecules for bone regenerative engineering: preclinical studies and potential clinical applications.

    PubMed

    Laurencin, Cato T; Ashe, Keshia M; Henry, Nicole; Kan, Ho Man; Lo, Kevin W-H

    2014-06-01

    Stimulation of bone regeneration using growth factors is a promising approach for musculoskeletal regenerative engineering. However, common limitations with protein growth factors, such as high manufacturing costs, protein instability, contamination issues, and unwanted immunogenic responses of the host reduce potential clinical applications. New strategies for bone regeneration that involve inexpensive and stable small molecules can obviate these problems and have a significant impact on the treatment of skeletal injury and diseases. Over the past decade, a large number of small molecules with the potential of regenerating skeletal tissue have been reported in the literature. Here, we review this literature, paying specific attention to the prospects for small molecule-based bone-regenerative engineering. We also review the preclinical study of small molecules associated with bone regeneration. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Closed-cycle hydrogen-fueled engine

    NASA Technical Reports Server (NTRS)

    Laumann, E. A.; Reynolds, R. K.

    1977-01-01

    Innovation avoids pollution by retaining combustion products. Potential uses include applicability to pollution-free powerplant using intermittent solar energy. Engine parts are fabricated from silicon carbide, silicon nitride, stainless steel, and other high-tensile strength materials.

  4. The School Advanced Ventilation Engineering Software (SAVES)

    EPA Pesticide Factsheets

    The School Advanced Ventilation Engineering Software (SAVES) package is a tool to help school designers assess the potential financial payback and indoor humidity control benefits of Energy Recovery Ventilation (ERV) systems for school applications.

  5. Supersonic through-flow fan assessment

    NASA Technical Reports Server (NTRS)

    Kepler, C. E.; Champagne, G. A.

    1988-01-01

    A study was conducted to assess the performance potential of a supersonic through-flow fan engine for supersonic cruise aircraft. It included a mean-line analysis of fans designed to operate with in-flow velocities ranging from subsonic to high supersonic speeds. The fan performance generated was used to estimate the performance of supersonic fan engines designed for four applications: a Mach 2.3 supersonic transport, a Mach 2.5 fighter, a Mach 3.5 cruise missile, and a Mach 5.0 cruise vehicle. For each application an engine was conceptualized, fan performance and engine performance calculated, weight estimates made, engine installed in a hypothetical vehicle, and mission analysis was conducted.

  6. Human umbilical cord derived matrix: A scaffold suitable for tissue engineering application.

    PubMed

    Dan, Pan; Velot, Émilie; Mesure, Benjamin; Groshenry, Guillaume; Bacharouche, Jalal; Decot, Véronique; Menu, Patrick

    2017-01-01

    Human tissue derived natural extracellular matrix (ECM) has great potential in tissue engineering. We sought to isolate extracellular matrix derived from human umbilical cord and test its potential in tissue engineering. An enzymatic method was applied to isolate and solubilized complete human umbilical cord derived matrix (hUCM). The obtained solution was analyzed for growth factors, collagen and residual DNA contents, then used to coat 2D and 3D surfaces for cell culture application. The hUCM was successfully isolated with trypsin digestion to acquire a solution containing various growth factors and collagen but no residual DNA. This hUCM solution can form a coating on 2D and 3D substrates suitable cell culture. We developed a new matrix derived from human source that can be further used in tissue engineering.

  7. Bio-Inspired Extreme Wetting Surfaces for Biomedical Applications

    PubMed Central

    Shin, Sera; Seo, Jungmok; Han, Heetak; Kang, Subin; Kim, Hyunchul; Lee, Taeyoon

    2016-01-01

    Biological creatures with unique surface wettability have long served as a source of inspiration for scientists and engineers. More specifically, materials exhibiting extreme wetting properties, such as superhydrophilic and superhydrophobic surfaces, have attracted considerable attention because of their potential use in various applications, such as self-cleaning fabrics, anti-fog windows, anti-corrosive coatings, drag-reduction systems, and efficient water transportation. In particular, the engineering of surface wettability by manipulating chemical properties and structure opens emerging biomedical applications ranging from high-throughput cell culture platforms to biomedical devices. This review describes design and fabrication methods for artificial extreme wetting surfaces. Next, we introduce some of the newer and emerging biomedical applications using extreme wetting surfaces. Current challenges and future prospects of the surfaces for potential biomedical applications are also addressed. PMID:28787916

  8. Dual-fuel natural gas/diesel engines: Technology, performance, and emissions

    NASA Astrophysics Data System (ADS)

    Turner, S. H.; Weaver, C. S.

    1994-11-01

    An investigation of current dual-fuel natural gas/diesel engine design, performance, and emissions was conducted. The most pressing technological problems associated with dual-fuel engine use were identified along with potential solutions. It was concluded that dual-fuel engines can achieve low NO(sub x) and particulate emissions while retaining fuel-efficiency and BMEP levels comparable to those of diesel engines. The investigation also examined the potential economic impact of dual-fuel engines in diesel-electric locomotives, marine vessels, farm equipment, construction, mining, and industrial equipment, and stand-alone electricity generation systems. Recommendations for further additional funding to support research, development, and demonstration in these applications were then presented.

  9. Real engineering in a virtual world

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Deitz, D.

    1995-07-01

    VR technology can be thought of as the next point on a continuum that leads from 1-D data (such as the text and numbers on a finite element analysis printout), through 2-D drawings and 3-D solid models to 4-D digital prototypes that eventually will have texture and weight and can be held in one`s hand. If it lives up to its potential, VR could become just another tool--like 3-D CAD/CAM systems and FEA software--that can be used to pursue continuous improvements in design and manufacturing processes. For example VR could help manufacturers reduce the number of prototypes and engineering changemore » orders (ECOs) generated during the product life cycle. Virtual reality could also be used to promote concurrent engineering. Because realistic virtual models are easier to interpret and interrogate than 2-D drawings or even 3-D solid models, they have the potential to simplify design reviews. They could also make it easier for non-engineers (such as salespeople and potential customers) to contribute to the design process. VR technology still has a way to go before it becomes a standard engineering tool, however. Peripheral devices are still being perfected, and engineers seem to agree that the jury`s still out on which peripherals are most appropriate for which applications. Further, advanced VR applications are largely confined to research and development departments of large corporations or to public and private research centers. Finally, potential users will have to wait a few years before desktop computers are powerful enough to run such applications--and inexpensive enough to survive a cost-benefit analysis.« less

  10. Integrating Rehabilitation Engineering Technology With Biologics

    PubMed Central

    Collinger, Jennifer L.; Dicianno, Brad E.; Weber, Douglas J.; Cui, Xinyan Tracy; Wang, Wei; Brienza, David M.; Boninger, Michael L.

    2017-01-01

    Rehabilitation engineers apply engineering principles to improve function or to solve challenges faced by persons with disabilities. It is critical to integrate the knowledge of biologics into the process of rehabilitation engineering to advance the field and maximize potential benefits to patients. Some applications in particular demonstrate the value of a symbiotic relationship between biologics and rehabilitation engineering. In this review we illustrate how researchers working with neural interfaces and integrated prosthetics, assistive technology, and biologics data collection are currently integrating these 2 fields. We also discuss the potential for further integration of biologics and rehabilitation engineering to deliver the best technologies and treatments to patients. Engineers and clinicians must work together to develop technologies that meet clinical needs and are accessible to the intended patient population. PMID:21703573

  11. Assessment of a 40-kilowatt stirling engine for underground mining applications

    NASA Technical Reports Server (NTRS)

    Cairelli, J. E.; Kelm, G. G.; Slaby, J. G.

    1982-01-01

    An assessment of alternative power souces for underground mining applications was performed. A 40-kW Stirling research engine was tested to evaluate its performance and emission characteristics when operated with helium working gas and diesel fuel. The engine, the test facility, and the test procedures are described. Performance and emission data for the engine operating with helium working gas and diesel fuel are reported and compared with data obtained with hydrogen working gas and unleaded gasoline fuel. Helium diesel test results are compared with the characteristics of current diesel engines and other Stirling engines. External surface temperature data are also presented. Emission and temperature results are compared with the Federal requirements for diesel underground mine engines. The durability potential of Stirling engines is discussed on the basis of the experience gaind during the engine tests.

  12. Propulsion technology needs for advanced space transportation systems. [orbit maneuvering engine (space shuttle), space shuttle boosters

    NASA Technical Reports Server (NTRS)

    Gregory, J. W.

    1975-01-01

    Plans are formulated for chemical propulsion technology programs to meet the needs of advanced space transportation systems from 1980 to the year 2000. The many possible vehicle applications are reviewed and cataloged to isolate the common threads of primary propulsion technology that satisfies near term requirements in the first decade and at the same time establish the technology groundwork for various potential far term applications in the second decade. Thrust classes of primary propulsion engines that are apparent include: (1) 5,000 to 30,000 pounds thrust for upper stages and space maneuvering; and (2) large booster engines of over 250,000 pounds thrust. Major classes of propulsion systems and the important subdivisions of each class are identified. The relative importance of each class is discussed in terms of the number of potential applications, the likelihood of that application materializing, and the criticality of the technology needed. Specific technology programs are described and scheduled to fulfill the anticipated primary propulsion technology requirements.

  13. Applicability of advanced automotive heat engines to solar thermal power

    NASA Technical Reports Server (NTRS)

    Beremand, D. G.; Evans, D. G.; Alger, D. L.

    1981-01-01

    The requirements of a solar thermal power system are reviewed and compared with the predicted characteristics of automobile engines under development. A good match is found in terms of power level and efficiency when the automobile engines, designed for maximum powers of 65-100 kW (87 to 133 hp) are operated to the nominal 20-40 kW electric output requirement of the solar thermal application. At these reduced power levels it appears that the automotive gas turbine and Stirling engines have the potential to deliver the 40+ percent efficiency goal of the solar thermal program.

  14. Applicability of advanced automotive heat engines to solar thermal power

    NASA Astrophysics Data System (ADS)

    Beremand, D. G.; Evans, D. G.; Alger, D. L.

    The requirements of a solar thermal power system are reviewed and compared with the predicted characteristics of automobile engines under development. A good match is found in terms of power level and efficiency when the automobile engines, designed for maximum powers of 65-100 kW (87 to 133 hp) are operated to the nominal 20-40 kW electric output requirement of the solar thermal application. At these reduced power levels it appears that the automotive gas turbine and Stirling engines have the potential to deliver the 40+ percent efficiency goal of the solar thermal program.

  15. Recent advances in engineering microparticles and their nascent utilization in biomedical delivery and diagnostic applications.

    PubMed

    Choi, Andrew; Seo, Kyoung Duck; Kim, Do Wan; Kim, Bum Chang; Kim, Dong Sung

    2017-02-14

    Complex microparticles (MPs) bearing unique characteristics such as well-tailored sizes, various morphologies, and multi-compartments have been attempted to be produced by many researchers in the past decades. However, a conventionally used method of fabricating MPs, emulsion polymerization, has a limitation in achieving the aforementioned characteristics and several approaches such as the microfluidics-assisted (droplet-based microfluidics and flow lithography-based microfluidics), electrohydrodynamics (EHD)-based, centrifugation-based, and template-based methods have been recently suggested to overcome this limitation. The outstanding features of complex MPs engineered through these suggested methods have provided new opportunities for MPs to be applied in a wider range of applications including cell carriers, drug delivery agents, active pigments for display, microsensors, interface stabilizers, and catalyst substrates. Overall, the engineered MPs expose their potential particularly in the field of biomedical engineering as the increased complexity in the engineered MPs fulfills well the requirements of the high-end applications. This review outlines the current trends of newly developed techniques used for engineered MPs fabrication and focuses on the current state of engineered MPs in biomedical applications.

  16. High-Temperature Alloys for Automotive Stirling Engines

    NASA Technical Reports Server (NTRS)

    Stephens, J. R.; Titran, R. H.

    1986-01-01

    Stirling engine is external-combustion engine that offers fuel economy, low emissions, low noise, and low vibrations. One of most critical areas in engine development concerns material selection for component parts. Alloys CG-27 and XF-818 identified capable of withstanding rigorous requirements of automotive Stirling engine. Alloys chosen for availability, performance, and manufacturability. Advanced iron-base alloys have potential for variety of applications, including stationary solar-power systems.

  17. Rotary engine developments at Curtiss-Wright over the past 20 years and review of general aviation engine potential. [with direct chamber injection

    NASA Technical Reports Server (NTRS)

    Jones, C.

    1978-01-01

    The development of the rotary engine as a viable power plant capable of wide application is reviewed. Research results on the stratified charge engine with direct chamber injection are included. Emission control, reduced fuel consumption, and low noise level are among the factors discussed in terms of using the rotary engine in general aviation aircraft.

  18. Multilayer scaffolds in orthopaedic tissue engineering.

    PubMed

    Atesok, Kivanc; Doral, M Nedim; Karlsson, Jon; Egol, Kenneth A; Jazrawi, Laith M; Coelho, Paulo G; Martinez, Amaury; Matsumoto, Tomoyuki; Owens, Brett D; Ochi, Mitsuo; Hurwitz, Shepard R; Atala, Anthony; Fu, Freddie H; Lu, Helen H; Rodeo, Scott A

    2016-07-01

    The purpose of this study was to summarize the recent developments in the field of tissue engineering as they relate to multilayer scaffold designs in musculoskeletal regeneration. Clinical and basic research studies that highlight the current knowledge and potential future applications of the multilayer scaffolds in orthopaedic tissue engineering were evaluated and the best evidence collected. Studies were divided into three main categories based on tissue types and interfaces for which multilayer scaffolds were used to regenerate: bone, osteochondral junction and tendon-to-bone interfaces. In vitro and in vivo studies indicate that the use of stratified scaffolds composed of multiple layers with distinct compositions for regeneration of distinct tissue types within the same scaffold and anatomic location is feasible. This emerging tissue engineering approach has potential applications in regeneration of bone defects, osteochondral lesions and tendon-to-bone interfaces with successful basic research findings that encourage clinical applications. Present data supporting the advantages of the use of multilayer scaffolds as an emerging strategy in musculoskeletal tissue engineering are promising, however, still limited. Positive impacts of the use of next generation scaffolds in orthopaedic tissue engineering can be expected in terms of decreasing the invasiveness of current grafting techniques used for reconstruction of bone and osteochondral defects, and tendon-to-bone interfaces in near future.

  19. Therapeutic uses of microencapsulated genetically engineered cells.

    PubMed

    Chang, T M; Prakash, S

    1998-05-01

    Microencapsulated genetically engineered cells have the potential to treat a wide range of diseases. For example, in experimental animals, implanted microencapsulated cells have been used to secrete growth hormone to treat dwarfism, neurotrophic factors for amyotrophic lateral sclerosis, beta-endorphin to decrease pain, factor XI for hemophilia B, and nerve growth factors to protect axotomized neurons. For some applications, microencapsulated cells can even be given orally. They can be engineered to remove unwanted molecules from the body as they travel through the intestine, and are finally excreted in the stool without being retained in the body. This application has enormous potential for the removal of urea in kidney failure, ammonia in liver failure and amino acids such as phenylalanine in phenylketonuria and other inborn errors of metabolism.

  20. The Effects of Discipline on the Application of Learning Object Metadata in UK Higher Education: The Case of the Jorum Repository

    ERIC Educational Resources Information Center

    Balatsoukas, Panos; O'Brien, Ann; Morris, Anne

    2011-01-01

    Introduction: This paper reports on the findings of a study investigating the potential effects of discipline (sciences and engineering versus humanities and social sciences) on the application of the Institute of Electrical and Electronic Engineers learning object metadata elements for the description of learning objects in the Jorum learning…

  1. Free-piston Stirling engine/linear alternator 1000-hour endurance test

    NASA Technical Reports Server (NTRS)

    Rauch, J.; Dochat, G.

    1985-01-01

    The Free Piston Stirling Engine (FPSE) has the potential to be a long lived, highly reliable, power conversion device attractive for many product applications such as space, residential or remote site power. The purpose of endurance testing the FPSE was to demonstrate its potential for long life. The endurance program was directed at obtaining 1000 operational hours under various test conditions: low power, full stroke, duty cycle and stop/start. Critical performance parameters were measured to note any change and/or trend. Inspections were conducted to measure and compare critical seal/bearing clearances. The engine performed well throughout the program, completing more than 1100 hours. Hardware inspection, including the critical clearances, showed no significant change in hardware or clearance dimensions. The performance parameters did not exhibit any increasing or decreasing trends. The test program confirms the potential for long life FPSE applications.

  2. Graphene-based materials for tissue engineering.

    PubMed

    Shin, Su Ryon; Li, Yi-Chen; Jang, Hae Lin; Khoshakhlagh, Parastoo; Akbari, Mohsen; Nasajpour, Amir; Zhang, Yu Shrike; Tamayol, Ali; Khademhosseini, Ali

    2016-10-01

    Graphene and its chemical derivatives have been a pivotal new class of nanomaterials and a model system for quantum behavior. The material's excellent electrical conductivity, biocompatibility, surface area and thermal properties are of much interest to the scientific community. Two-dimensional graphene materials have been widely used in various biomedical research areas such as bioelectronics, imaging, drug delivery, and tissue engineering. In this review, we will highlight the recent applications of graphene-based materials in tissue engineering and regenerative medicine. In particular, we will discuss the application of graphene-based materials in cardiac, neural, bone, cartilage, skeletal muscle, and skin/adipose tissue engineering. We will also discuss the potential risk factors of graphene-based materials in tissue engineering. In conclusion, we will outline the opportunities in the usage of graphene-based materials for clinical applications. Published by Elsevier B.V.

  3. Potential of Diesel Engine, Emission Technology

    DOT National Transportation Integrated Search

    1980-03-01

    This report surveys diesel engine emission technologies applicable to passenger cars and light trucks. The general design and operating features are presented and discussed. Current and state-of-the-art concepts are reviewed with the focus on control...

  4. Human iPSC-derived cardiomyocytes and tissue engineering strategies for disease modeling and drug screening.

    PubMed

    Smith, Alec S T; Macadangdang, Jesse; Leung, Winnie; Laflamme, Michael A; Kim, Deok-Ho

    Improved methodologies for modeling cardiac disease phenotypes and accurately screening the efficacy and toxicity of potential therapeutic compounds are actively being sought to advance drug development and improve disease modeling capabilities. To that end, much recent effort has been devoted to the development of novel engineered biomimetic cardiac tissue platforms that accurately recapitulate the structure and function of the human myocardium. Within the field of cardiac engineering, induced pluripotent stem cells (iPSCs) are an exciting tool that offer the potential to advance the current state of the art, as they are derived from somatic cells, enabling the development of personalized medical strategies and patient specific disease models. Here we review different aspects of iPSC-based cardiac engineering technologies. We highlight methods for producing iPSC-derived cardiomyocytes (iPSC-CMs) and discuss their application to compound efficacy/toxicity screening and in vitro modeling of prevalent cardiac diseases. Special attention is paid to the application of micro- and nano-engineering techniques for the development of novel iPSC-CM based platforms and their potential to advance current preclinical screening modalities. Published by Elsevier Inc.

  5. A simplified gross thrust computing technique for an afterburning turbofan engine

    NASA Technical Reports Server (NTRS)

    Hamer, M. J.; Kurtenbach, F. J.

    1978-01-01

    A simplified gross thrust computing technique extended to the F100-PW-100 afterburning turbofan engine is described. The technique uses measured total and static pressures in the engine tailpipe and ambient static pressure to compute gross thrust. Empirically evaluated calibration factors account for three-dimensional effects, the effects of friction and mass transfer, and the effects of simplifying assumptions for solving the equations. Instrumentation requirements and the sensitivity of computed thrust to transducer errors are presented. NASA altitude facility tests on F100 engines (computed thrust versus measured thrust) are presented, and calibration factors obtained on one engine are shown to be applicable to the second engine by comparing the computed gross thrust. It is concluded that this thrust method is potentially suitable for flight test application and engine maintenance on production engines with a minimum amount of instrumentation.

  6. 40 CFR 1054.690 - What bond requirements apply for certified engines?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) Before introducing certified engines into U.S. commerce, you must post a bond to cover any potential... importing engines that have been certified by someone else. Note that you might also post bond under this... test conducted by EPA officials or having been found by EPA to be noncompliant under applicable...

  7. 40 CFR 1054.690 - What bond requirements apply for certified engines?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) Before introducing certified engines into U.S. commerce, you must post a bond to cover any potential... importing engines that have been certified by someone else. Note that you might also post bond under this... test conducted by EPA officials or having been found by EPA to be noncompliant under applicable...

  8. 40 CFR 1054.690 - What bond requirements apply for certified engines?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) Before introducing certified engines into U.S. commerce, you must post a bond to cover any potential... importing engines that have been certified by someone else. Note that you might also post bond under this... test conducted by EPA officials or having been found by EPA to be noncompliant under applicable...

  9. 40 CFR 1054.690 - What bond requirements apply for certified engines?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) Before introducing certified engines into U.S. commerce, you must post a bond to cover any potential... importing engines that have been certified by someone else. Note that you might also post bond under this... test conducted by EPA officials or having been found by EPA to be noncompliant under applicable...

  10. 40 CFR 1054.690 - What bond requirements apply for certified engines?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) Before introducing certified engines into U.S. commerce, you must post a bond to cover any potential... importing engines that have been certified by someone else. Note that you might also post bond under this... test conducted by EPA officials or having been found by EPA to be noncompliant under applicable...

  11. Evaluation of Potential Military Applications of Stirling Engines

    DTIC Science & Technology

    1988-07-01

    ES- 1 C. Generator Sn-,s (Mobile Electric Power) ..................................... ES-3 1. General Purpose...ES-2 ES-2. General Purpose Generator Sets in the US DoD Inventory ..................... ES-4 ES-3. Comparison of Typical Diesel Engines Used in DoD...Standard Family Generator Sets and Stirling Engines ....................................... ES-4 ES-4. Underwater Energy Storage

  12. EXTENSION OF COMPUTER-AIDED PROCESS ENGINEERING APPLICATIONS TO ENVIRONMENTAL LIFE CYCLE ASSESSMENT AND SUPPLY CHAIN MANAGEMENT

    EPA Science Inventory

    The potential of computer-aided process engineering (CAPE) tools to enable process engineers to improve the environmental performance of both their processes and across the life cycle (from cradle-to-grave) has long been proffered. However, this use of CAPE has not been fully ach...

  13. Nano scaffolds and stem cell therapy in liver tissue engineering

    NASA Astrophysics Data System (ADS)

    Montaser, Laila M.; Fawzy, Sherin M.

    2015-08-01

    Tissue engineering and regenerative medicine have been constantly developing of late due to the major progress in cell and organ transplantation, as well as advances in materials science and engineering. Although stem cells hold great potential for the treatment of many injuries and degenerative diseases, several obstacles must be overcome before their therapeutic application can be realized. These include the development of advanced techniques to understand and control functions of micro environmental signals and novel methods to track and guide transplanted stem cells. A major complication encountered with stem cell therapies has been the failure of injected cells to engraft to target tissues. The application of nanotechnology to stem cell biology would be able to address those challenges. Combinations of stem cell therapy and nanotechnology in tissue engineering and regenerative medicine have achieved significant advances. These combinations allow nanotechnology to engineer scaffolds with various features to control stem cell fate decisions. Fabrication of Nano fiber cell scaffolds onto which stem cells can adhere and spread, forming a niche-like microenvironment which can guide stem cells to proceed to heal damaged tissues. In this paper, current and emergent approach based on stem cells in the field of liver tissue engineering is presented for specific application. The combination of stem cells and tissue engineering opens new perspectives in tissue regeneration for stem cell therapy because of the potential to control stem cell behavior with the physical and chemical characteristics of the engineered scaffold environment.

  14. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Furey, M.J.; Kajdas, C.; Kaltenbach, K.W.

    Advanced lubrication technologies based on the concept of tribopolymerization as a mechanism of boundary lubrication are described. Advantages of this approach as well as potential applications which could have an impact on the design, manufacture, and performance of existing and future automotive engines are presented and discussed. Tribopolymerization, a novel concept of molecular design developed by Furey and Kajdas, involves the continuous formation of thin polymeric films on rubbing surfaces; the protective films formed are self-replenishing. The antiwear compounds developed from this technology are effective with metals as well as ceramics and in the liquid as well as vapor phases.more » Furthermore, they are ashless and contain no harmful phosphorus or sulfur; and many are biodegradable. Thus, potential applications of this technology are diverse and include a variety of cost/performance/energy/environmental advantages. Examples include the following: (a) machining and cutting applications using thin films to reduce friction and ceramic tool wear; (b) the lubrication of ceramic engines (e.g., low heat rejection diesel engines) or ceramic components; (c) the development of ashless lubricants for existing and future automotive engines to reduce exhaust catalyst poisoning and environmental emissions; (d) ashless antiwear or ``lubricity`` additives for fuels, including gasoline, diesel and jet fuel; (e) vapor phase applications of this technology to high temperature gaseous systems or to fuel injector wear problems associated with the use of natural gas engines; and (f) the use of the concept of tribopolymerization as an enabling technology in the development of new engines and new automotive propulsion systems.« less

  15. Advanced control for airbreathing engines, volume 2: General Electric aircraft engines

    NASA Technical Reports Server (NTRS)

    Bansal, Indar

    1993-01-01

    The application of advanced control concepts to air breathing engines may yield significant improvements in aircraft/engine performance and operability. Screening studies of advanced control concepts for air breathing engines were conducted by three major domestic aircraft engine manufacturers to determine the potential impact of concepts on turbine engine performance and operability. The purpose of the studies was to identify concepts which offered high potential yet may incur high research and development risk. A target suite of proposed advanced control concepts was formulated and evaluated in a two phase study to quantify each concept's impact on desired engine characteristics. To aid in the evaluation specific aircraft/engine combinations were considered: a Military High Performance Fighter mission, a High Speed Civil Transport mission, and a Civil Tiltrotor mission. Each of the advanced control concepts considered in the study are defined and described. The concept potential impact on engine performance was determined. Relevant figures of merit on which to evaluate the concepts are determined. Finally, the concepts are ranked with respect to the target aircraft/engine missions. A final report describing the screening studies was prepared by each engine manufacturer. Volume 2 of these reports describes the studies performed by GE Aircraft Engines.

  16. Applications and issues of GIS as tool for civil engineering modeling

    USGS Publications Warehouse

    Miles, S.B.; Ho, C.L.

    1999-01-01

    A tool that has proliferated within civil engineering in recent years is geographic information systems (GIS). The goal of a tool is to supplement ability and knowledge that already exists, not to serve as a replacement for that which is lacking. To secure the benefits and avoid misuse of a burgeoning tool, engineers must understand the limitations, alternatives, and context of the tool. The common benefits of using GIS as a supplement to engineering modeling are summarized. Several brief case studies of GIS modeling applications are taken from popular civil engineering literature to demonstrate the wide use and varied implementation of GIS across the discipline. Drawing from the case studies, limitations regarding traditional GIS data models find the implementation of civil engineering models within current GIS are identified and countered by discussing the direction of the next generation of GIS. The paper concludes by highlighting the potential for the misuse of GIS in the context of engineering modeling and suggests that this potential can be reduced through education and awareness. The goal of this paper is to promote awareness of the issues related to GIS-based modeling and to assist in the formulation of questions regarding the application of current GIS. The technology has experienced much publicity of late, with many engineers being perhaps too excited about the usefulness of current GIS. An undoubtedly beneficial side effect of this, however, is that engineers are becoming more aware of GIS and, hopefully, the associated subtleties. Civil engineers must stay informed of GIS issues and progress, but more importantly, civil engineers must inform the GIS community to direct the technology development optimally.

  17. Genetic engineering possibilities for CELSS: A bibliography and summary of techniques

    NASA Technical Reports Server (NTRS)

    Johnson, E. J.

    1982-01-01

    A bibliography of the most useful techniques employed in genetic engineering of higher plants, bacteria associated with plants, and plant cell cultures is provided. A resume of state-of-the-art genetic engineering of plants and bacteria is presented. The potential application of plant bacterial genetic engineering to CELSS (Controlled Ecological Life Support System) program and future research needs are discussed.

  18. Polymer microarray technology for stem cell engineering

    PubMed Central

    Coyle, Robert; Jia, Jia; Mei, Ying

    2015-01-01

    Stem cells hold remarkable promise for applications in tissue engineering and disease modeling. During the past decade, significant progress has been made in developing soluble factors (e.g., small molecules and growth factors) to direct stem cells into a desired phenotype. However, the current lack of suitable synthetic materials to regulate stem cell activity has limited the realization of the enormous potential of stem cells. This can be attributed to a large number of materials properties (e.g., chemical structures and physical properties of materials) that can affect stem cell fate. This makes it challenging to design biomaterials to direct stem cell behavior. To address this, polymer microarray technology has been developed to rapidly identify materials for a variety of stem cell applications. In this article, we summarize recent developments in polymer array technology and their applications in stem cell engineering. Statement of significance Stem cells hold remarkable promise for applications in tissue engineering and disease modeling. In the last decade, significant progress has been made in developing chemically defined media to direct stem cells into a desired phenotype. However, the current lack of the suitable synthetic materials to regulate stem cell activities has been limiting the realization of the potential of stem cells. This can be attributed to the number of variables in material properties (e.g., chemical structures and physical properties) that can affect stem cells. Polymer microarray technology has shown to be a powerful tool to rapidly identify materials for a variety of stem cell applications. Here we summarize recent developments in polymer array technology and their applications in stem cell engineering. PMID:26497624

  19. Recent advancements in carbon nanofiber and carbon nanotube applications in drug delivery and tissue engineering.

    PubMed

    Stout, David A

    2015-01-01

    Since the discovery and synthesis of carbon nanotubes (CNTs) and carbon nanofibers (CNFs) over a decade ago, researchers have envisioned and discovered new potential applications for these materials. CNTs and CNFs have rapidly become a platform technology for a variety of uses, including biomedical applications due to their mechanical, electrical, thermal, optical and structural properties. CNTs and CNFs are also advantageous due to their ability to be produced in many different shapes and sizes. Since their discovery, of the many imaginable applications, CNTs and CNFs have gained a significant amount of attention and therapeutic potential in tissue engineering and drug delivery applications. In recent years, CNTs and CNFs have made significant contributions in designing new strategies for, delivery of pharmaceuticals, genes and molecular probes into cells, stem cell therapies and assisting in tissue regeneration. Furthermore, it is widely expressed that these materials will significantly contribute to the next generation of health care technologies in treating diseases and contributing to tissue growth. Hence, this review seeks to explore the recent advancements, current status and limitations of CNTs and CNFs for drug delivery and tissue engineering applications.

  20. Advanced General Aviation Turbine Engine (GATE) study

    NASA Technical Reports Server (NTRS)

    Smith, R.; Benstein, E. H.

    1979-01-01

    The small engine technology requirements suitable for general aviation service in the 1987 to 1988 time frame were defined. The market analysis showed potential United States engines sales of 31,500 per year providing that the turbine engine sales price approaches current reciprocating engine prices. An optimum engine design was prepared for four categories of fixed wing aircraft and for rotary wing applications. A common core approach was derived from the optimum engines that maximizes engine commonality over the power spectrum with a projected price competitive with reciprocating piston engines. The advanced technology features reduced engine cost, approximately 50 percent compared with current technology.

  1. Application of advanced coating techniques to rocket engine components

    NASA Technical Reports Server (NTRS)

    Verma, S. K.

    1988-01-01

    The materials problem in the space shuttle main engine (SSME) is reviewed. Potential coatings and the method of their application for improved life of SSME components are discussed. A number of advanced coatings for turbine blade components and disks are being developed and tested in a multispecimen thermal fatigue fluidized bed facility at IIT Research Institute. This facility is capable of producing severe strains of the degree present in blades and disk components of the SSME. The potential coating systems and current efforts at IITRI being taken for life extension of the SSME components are summarized.

  2. Composite Material Application to Liquid Rocket Engines

    NASA Technical Reports Server (NTRS)

    Judd, D. C.

    1982-01-01

    The substitution of reinforced plastic composite (RPC) materials for metal was studied. The major objectives were to: (1) determine the extent to which composite materials can be beneficially used in liquid rocket engines; (2) identify additional technology requirements; and (3) determine those areas which have the greatest potential for return. Weight savings, fabrication costs, performance, life, and maintainability factors were considered. Two baseline designs, representative of Earth to orbit and orbit to orbit engine systems, were selected. Weight savings are found to be possible for selected components with the substitution of materials for metal. Various technology needs are identified before RPC material can be used in rocket engine applications.

  3. Screening studies of advanced control concepts for airbreathing engines

    NASA Technical Reports Server (NTRS)

    Ouzts, Peter J.; Lorenzo, Carl F.; Merrill, Walter C.

    1993-01-01

    The application of advanced control concepts to airbreathing engines may yield significant improvements in aircraft/engine performance and operability. Accordingly, the NASA Lewis Research Center has conducted screening studies of advanced control concepts for airbreathing engines to determine their potential impact on turbine engine performance and operability. The purpose of the studies was to identify concepts which offered high potential yet may incur high research and development risk. A target suite of proposed concepts was formulated by NASA and industry. These concepts were evaluated in a two phase study to quantify each concept's impact on desired engine characteristics. To aid in the evaluation, three target aircraft/engine combinations were considered: a military high performance fighter mission, a high speed civil transport mission, and a civil tiltrotor mission. Each of the advanced control concepts considered in the study were defined and described. The concept's potential impact on engine performance was determined. Relevant figures of merit on which to evaluate the concepts were also determined. Finally, the concepts were ranked with respect to the target aircraft/engine missions.

  4. Fiber Bragg grating applications in biomechanics

    NASA Astrophysics Data System (ADS)

    Kalinowski, Hypolito José

    2008-04-01

    Fibre Bragg gratings are promising sensors for medical and bioengineering applications, mainly because of their small dimensions and chemical inertness. Although few examples of such applications are published up to date, we present results that show the expected potential for FBG sensor applications in biomechanical engineering.

  5. Therapeutic cloning applications for organ transplantation.

    PubMed

    Koh, Chester J; Atala, Anthony

    2004-04-01

    A severe shortage of donor organs available for transplantation in the United States leaves patients suffering from diseased and injured organs with few treatment options. Scientists in the field of tissue engineering apply the principles of cell transplantation, material science, and engineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Therapeutic cloning, where the nucleus from a donor cell is transferred into an enucleated oocyte in order to extract pluripotent embryonic stem cells, offers a potentially limitless source of cells for tissue engineering applications. The present chapter reviews recent advances that have occurred in therapeutic cloning and tissue engineering and describes applications of these new technologies that may offer novel therapies for patients with end-stage organ failure. Copyright 2004 Elsevier B.V.

  6. FY 2007 Progress Report for Advanced Combustion Engine Technologies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None, None

    2007-12-01

    Advanced combustion engines have great potential for achieving dramatic energy efficiency improvements in light-duty vehicle applications, where it is suited to both conventional and hybrid- electric powertrain configurations. Light-duty vehicles with advanced combustion engines can compete directly with gasoline engine hybrid vehicles in terms of fuel economy and consumer-friendly driving characteristics; also, they are projected to have energy efficiencies that are competitive with hydrogen fuel cell vehicles when used in hybrid applications.Advanced engine technologies being researched and developed by the Advanced Combustion Engine R&D Sub-Program will also allow the use of hydrogen as a fuel in ICEs and will providemore » an energy-efficient interim hydrogen-based powertrain technology during the transition to hydrogen/fuelcell-powered transportation vehicles.« less

  7. Aircraft engine pollution reduction.

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.

    1972-01-01

    The effect of engine operation on the types and levels of the major aircraft engine pollutants is described and the major factors governing the formation of these pollutants during the burning of hydrocarbon fuel are discussed. Methods which are being explored to reduce these pollutants are discussed and their application to several experimental research programs are pointed out. Results showing significant reductions in the levels of carbon monoxide, unburned hydrocarbons, and oxides of nitrogen obtained from experimental combustion research programs are presented and discussed to point out potential application to aircraft engines. An experimental program designed to develop and demonstrate these and other advanced, low pollution combustor design methods is described. Results that have been obtained to date indicate considerable promise for reducing advanced engine exhaust pollutants to levels significantly below current engines.

  8. GLobal Integrated Design Environment (GLIDE): A Concurrent Engineering Application

    NASA Technical Reports Server (NTRS)

    McGuire, Melissa L.; Kunkel, Matthew R.; Smith, David A.

    2010-01-01

    The GLobal Integrated Design Environment (GLIDE) is a client-server software application purpose-built to mitigate issues associated with real time data sharing in concurrent engineering environments and to facilitate discipline-to-discipline interaction between multiple engineers and researchers. GLIDE is implemented in multiple programming languages utilizing standardized web protocols to enable secure parameter data sharing between engineers and researchers across the Internet in closed and/or widely distributed working environments. A well defined, HyperText Transfer Protocol (HTTP) based Application Programming Interface (API) to the GLIDE client/server environment enables users to interact with GLIDE, and each other, within common and familiar tools. One such common tool, Microsoft Excel (Microsoft Corporation), paired with its add-in API for GLIDE, is discussed in this paper. The top-level examples given demonstrate how this interface improves the efficiency of the design process of a concurrent engineering study while reducing potential errors associated with manually sharing information between study participants.

  9. Integrated computational materials engineering: Tools, simulations and new applications

    DOE PAGES

    Madison, Jonathan D.

    2016-03-30

    Here, Integrated Computational Materials Engineering (ICME) is a relatively new methodology full of tremendous potential to revolutionize how science, engineering and manufacturing work together. ICME was motivated by the desire to derive greater understanding throughout each portion of the development life cycle of materials, while simultaneously reducing the time between discovery to implementation [1,2].

  10. Recent progress in interfacial tissue engineering approaches for osteochondral defects.

    PubMed

    Castro, Nathan J; Hacking, S Adam; Zhang, Lijie Grace

    2012-08-01

    This review provides a brief synopsis of the anatomy and physiology of the osteochondral interface, scaffold-based and non-scaffold based approaches for engineering both tissues independently as well as recent developments in the manufacture of gradient constructs. Novel manufacturing techniques and nanotechnology will be discussed with potential application in osteochondral interfacial tissue engineering.

  11. Biopharmaceutics and Therapeutic Potential of Engineered Nanomaterials

    PubMed Central

    Liang, Xing-Jie; Chen, Chunying; Zhao, Yuliang; Jia, Lee; Wang, Paul C.

    2009-01-01

    Engineered nanomaterials are at the leading edge of the rapidly developing nanosciences and are founding an important class of new materials with specific physicochemical properties different from bulk materials with the same compositions. The potential for nanomaterials is rapidly expanding with novel applications constantly being explored in different areas. The unique size-dependent properties of nanomaterials make them very attractive for pharmaceutical applications. Investigations of physical, chemical and biological properties of engineered nanomaterials have yielded valuable information. Cytotoxic effects of certain engineered nanomaterials towards malignant cells form the basis for one aspect of nanomedicine. It is inferred that size, three dimensional shape, hydrophobicity and electronic configurations make them an appealing subject in medicinal chemistry. Their unique structure coupled with immense scope for derivatization forms a base for exciting developments in therapeutics. This review article addresses the fate of absorption, distribution, metabolism and excretion (ADME) of engineered nanoparticles in vitro and in vivo. It updates the distinctive methodology used for studying the biopharmaceutics of nanoparticles. This review addresses the future potential and safety concerns and genotoxicity of nanoparticle formulations in general. It particularly emphasizes the effects of nanoparticles on metabolic enzymes as well as the parenteral or inhalation administration routes of nanoparticle formulations. This paper illustrates the potential of nanomedicine by discussing biopharmaceutics of fullerene derivatives and their suitability for diagnostic and therapeutic purposes. Future direction is discussed as well. PMID:18855608

  12. Evaluation of the potential of the Stirling engine for heavy duty application

    NASA Technical Reports Server (NTRS)

    Meijer, R. J.; Ziph, B.

    1981-01-01

    A 150 hp four cylinder heavy duty Stirling engine was evaluated. The engine uses a variable stroke power control system, swashplate drive and ceramic insulation. The sensitivity of the design to engine size and heater temperature is investigated. Optimization shows that, with porous ceramics, indicated efficiencies as high as 52% can be achieved. It is shown that the gain in engine efficiency becomes insignificant when the heater temperature is raised above 200 degrees F.

  13. Advanced Turbine Technology Applications Project (ATTAP)

    NASA Technical Reports Server (NTRS)

    1991-01-01

    ATTAP activities were highlighted by test bed engine design and development activities; ceramic component design; materials and engine component characterization; ceramic component process development and fabrication; component rig testing; and test bed engine fabrication and testing. Specifically, ATTAP aims to develop and demonstrate the technology of structural ceramics that have the potential for competitive automotive engine life cycle cost and for operating for 3500 hours in a turbine engine environment at temperatures up to 1371 C (2500 F).

  14. 40 CFR 68.67 - Process hazard analysis.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) CHEMICAL ACCIDENT PREVENTION PROVISIONS Program 3 Prevention Program § 68.67 Process hazard analysis. (a... potential for catastrophic consequences. (3) Engineering and administrative controls applicable to the... engineering and administrative controls; (5) Stationary source siting; (6) Human factors; and (7) A...

  15. 40 CFR 68.67 - Process hazard analysis.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) CHEMICAL ACCIDENT PREVENTION PROVISIONS Program 3 Prevention Program § 68.67 Process hazard analysis. (a... potential for catastrophic consequences. (3) Engineering and administrative controls applicable to the... engineering and administrative controls; (5) Stationary source siting; (6) Human factors; and (7) A...

  16. 40 CFR 68.67 - Process hazard analysis.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) CHEMICAL ACCIDENT PREVENTION PROVISIONS Program 3 Prevention Program § 68.67 Process hazard analysis. (a... potential for catastrophic consequences. (3) Engineering and administrative controls applicable to the... engineering and administrative controls; (5) Stationary source siting; (6) Human factors; and (7) A...

  17. Advanced controls for airbreathing engines, volume 3: Allison gas turbine

    NASA Technical Reports Server (NTRS)

    Bough, R. M.

    1993-01-01

    The application of advanced control concepts to airbreathing engines may yield significant improvements in aircraft/engine performance and operability. Screening studies of advanced control concepts for airbreathing engines were conducted by three major domestic aircraft engine manufacturers to determine the potential impact of concepts on turbine engine performance and operability. The purpose of the studies was to identify concepts which offered high potential yet may incur high research and development risk. A target suite of proposed advanced control concepts was formulated and evaluated in a two-phase study to quantify each concept's impact on desired engine characteristics. To aid in the evaluation specific aircraft/engine combinations were considered: a Military High Performance Fighter mission, a High Speed Civil Transport mission, and a Civil Tiltrotor mission. Each of the advanced control concepts considered in the study are defined and described. The concept potential impact on engine performance was determined. Relevant figures of merit on which to evaluate the concepts are determined. Finally, the concepts are ranked with respect to the target aircraft/engine missions. A final report describing the screening studies was prepared by each engine manufacturer. Volume 3 of these reports describes the studies performed by the Allison Gas Turbine Division.

  18. Advanced control for airbreathing engines, volume 1: Pratt and Whitney

    NASA Technical Reports Server (NTRS)

    Ralph, J. A.

    1993-01-01

    The application of advanced control concepts to air breathing engines may yield significant improvements in aircraft/engine performance and operability. Screening studies of advanced control concepts for air breathing engines were conducted by three major domestic aircraft engine manufacturers to determine the potential impact of concepts on turbine engine performance and operability. The purpose of the studies was to identify concepts which offered high potential yet may incur high research and development risk. A target suite of proposed advanced control concepts was formulated and evaluated in a two phase study to quantify each concept's impact on desired engine characteristics. To aid in the evaluation specific aircraft/engine combinations were considered: a Military High Performance Fighter mission, a High Speed Civil Transport mission, and a Civil Tiltrotor mission. Each of the advanced control concepts considered in the study are defined and described. The concept potential impact on engine performance was determined. Relevant figures of merit on which to evaluate the concepts are determined. Finally, the concepts are ranked with respect to the target aircraft/engine missions. A final report describing the screening studies was prepared by each engine manufacturer. Volume 1 of these reports describes the studies performed by Pratt & Whitney.

  19. Jet engine applications for materials with nanometer-scale dimensions

    NASA Technical Reports Server (NTRS)

    Appleby, J. W., Jr.

    1995-01-01

    The performance of advanced military and commercial gas turbine engines is often linked to advances in materials technology. High performance gas turbine engines being developed require major material advances in strength, toughness, reduced density and improved temperature capability. The emerging technology of nanostructured materials has enormous potential for producing materials with significant improvements in these properties. Extraordinary properties demonstrated in the laboratory include material strengths approaching theoretical limit, ceramics that demonstrate ductility and toughness, and materials with ultra-high hardness. Nanostructured materials and coatings have the potential for meeting future gas turbine engine requirements for improved performance, reduced weight and lower fuel consumption.

  20. Jet engine applications for materials with nanometer-scale dimensions

    NASA Technical Reports Server (NTRS)

    Appleby, J. W., Jr.

    1995-01-01

    The performance of advanced military and commercial gas turbine engines is often linked to advances in materials technology. High performance gas turbine engines being developed require major material advances in strength, toughness, reduced density and improved temperature capability. The emerging technology of nanostructured materials has enormous potential for producing materials with significant improvements in these properties. Extraordinary properties demonstrated in the laboratory include material strengths approaching theoretical limit, ceramics that demonstrate ductility and toughness, and material with ultra-high hardness. Nanostructured materials and coatings have the potential for meeting future gas turbine engine requirements for improved performance, reduced weight and lower fuel consumption.

  1. Clinical translation of controlled protein delivery systems for tissue engineering.

    PubMed

    Spiller, Kara L; Vunjak-Novakovic, Gordana

    2015-04-01

    Strategies that utilize controlled release of drugs and proteins for tissue engineering have enormous potential to regenerate damaged organs and tissues. The multiple advantages of controlled release strategies merit overcoming the significant challenges to translation, including high costs and long, difficult regulatory pathways. This review highlights the potential of controlled release of proteins for tissue engineering and regenerative medicine. We specifically discuss treatment modalities that have reached preclinical and clinical trials, with emphasis on controlled release systems for bone tissue engineering, the most advanced application with several products already in clinic. Possible strategies to address translational and regulatory concerns are also discussed.

  2. Clinical translation of controlled protein delivery systems for tissue engineering

    PubMed Central

    Spiller, Kara L.; Vunjak-Novakovic, Gordana

    2013-01-01

    Strategies that utilize controlled release of drugs and proteins for tissue engineering have enormous potential to regenerate damaged organs and tissues. The multiple advantages of controlled release strategies merit overcoming the significant challenges to translation, including high costs and long, difficult regulatory pathways. This review highlights the potential of controlled release of proteins for tissue engineering and regenerative medicine. We specifically discuss treatment modalities that have reached preclinical and clinical trials, with emphasis on controlled release systems for bone tissue engineering, the most advanced application with several products already in clinic. Possible strategies to address translational and regulatory concerns are also discussed. PMID:25787736

  3. Therapeutic cloning and tissue engineering.

    PubMed

    Koh, Chester J; Atala, Anthony

    2004-01-01

    A severe shortage of donor organs available for transplantation in the United States leaves patients suffering from diseased and injured organs with few treatment options. Scientists in the field of tissue engineering apply the principles of cell transplantation, material science, and engineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Therapeutic cloning, where the nucleus from a donor cell is transferred into an enucleated oocyte in order to extract pluripotent embryonic stem cells, offers a potentially limitless source of cells for tissue engineering applications. The present chapter reviews recent advances that have occurred in therapeutic cloning and tissue engineering and describes applications of these new technologies that may offer novel therapies for patients with end-stage organ failure.

  4. Application of xanthan gum as polysaccharide in tissue engineering: A review.

    PubMed

    Kumar, Anuj; Rao, Kummara Madhusudana; Han, Sung Soo

    2018-01-15

    Xanthan gum is a microbial high molecular weight exo-polysaccharide produced by Xanthomonas bacteria (a Gram-negative bacteria genus that exhibits several different species) and it has widely been used as an additive in various industrial and biomedical applications such as food and food packaging, cosmetics, water-based paints, toiletries, petroleum, oil-recovery, construction and building materials, and drug delivery. Recently, it has shown great potential in issue engineering applications and a variety of modification methods have been employed to modify xanthan gum as polysaccharide for this purpose. However, xanthan gum-based biomaterials need further modification for several targeted applications due to some disadvantages (e.g., processing and mechanical performance of xanthan gum), where modified xanthan gum will be well suited for tissue engineering products. In this review, the current scenario of the use of xanthan gum for various tissue engineering applications, including its origin, structure, properties, modification, and processing for the preparation of the hydrogels and/or the scaffolds is precisely reviewed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Integrating rehabilitation engineering technology with biologics.

    PubMed

    Collinger, Jennifer L; Dicianno, Brad E; Weber, Douglas J; Cui, Xinyan Tracy; Wang, Wei; Brienza, David M; Boninger, Michael L

    2011-06-01

    Rehabilitation engineers apply engineering principles to improve function or to solve challenges faced by persons with disabilities. It is critical to integrate the knowledge of biologics into the process of rehabilitation engineering to advance the field and maximize potential benefits to patients. Some applications in particular demonstrate the value of a symbiotic relationship between biologics and rehabilitation engineering. In this review we illustrate how researchers working with neural interfaces and integrated prosthetics, assistive technology, and biologics data collection are currently integrating these 2 fields. We also discuss the potential for further integration of biologics and rehabilitation engineering to deliver the best technologies and treatments to patients. Engineers and clinicians must work together to develop technologies that meet clinical needs and are accessible to the intended patient population. Copyright © 2011 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

  6. Drug-device combination products in the twenty-first century: epinephrine auto-injector development using human factors engineering.

    PubMed

    Edwards, Eric S; Edwards, Evan T; Simons, F Estelle R; North, Robert

    2015-05-01

    The systematic application of human factors engineering (HFE) principles to the development of drug-device combination products, including epinephrine auto-injectors (EAIs), has the potential to improve the effectiveness and safety of drug administration. A PubMed search was performed to assess the role of HFE in the development of drug-device combination products. The following keywords were used in different combinations: 'human factors engineering,' 'human factors,' 'medical products,' 'epinephrine/adrenaline auto-injector,' 'healthcare' and 'patient safety.' This review provides a summary of HFE principles and their application to the development of drug-device combination products as advised by the US FDA. It also describes the HFE process that was applied to the development of Auvi-Q, a novel EAI, highlighting specific steps that occurred during the product-development program. For drug-device combination products, device labeling and usability are critical and have the potential to impact clinical outcomes. Application of HFE principles to the development of drug-delivery devices has the potential to improve product quality and reliability, reduce risk and improve patient safety when applied early in the development process. Additional clinical and real-world studies will confirm whether the application of HFE has helped to develop an EAI that better meets the needs of patients at risk of anaphylaxis.

  7. Microcomputed tomography characterization of neovascularization in bone tissue engineering applications.

    PubMed

    Young, Simon; Kretlow, James D; Nguyen, Charles; Bashoura, Alex G; Baggett, L Scott; Jansen, John A; Wong, Mark; Mikos, Antonios G

    2008-09-01

    Vasculogenesis and angiogenesis have been studied for decades using numerous in vitro and in vivo systems, fulfilling the need to elucidate the mechanisms involved in these processes and to test potential therapeutic agents that inhibit or promote neovascularization. Bone tissue engineering in particular has benefited from the application of proangiogenic strategies, considering the need for an adequate vascular supply during healing and the challenges associated with the vascularization of scaffolds implanted in vivo. Conventional methods of assessing the in vivo angiogenic response to tissue-engineered constructs tend to rely on a two-dimensional assessment of microvessel density within representative histological sections without elaboration of the true vascular tree. The introduction of microcomputed tomography (micro-CT) has recently allowed investigators to obtain a diverse range of high-resolution, three-dimensional characterization of structures, including renal, coronary, and hepatic vascular networks, as well as bone formation within healing defects. To date, few studies have utilized micro-CT to study the vascular response to an implanted tissue engineering scaffold. In this paper, conventional in vitro and in vivo models for studying angiogenesis will be discussed, followed by recent developments in the use of micro-CT for vessel imaging in bone tissue engineering research. A new study demonstrating the potential of contrast-enhanced micro-CT for the evaluation of in vivo neovascularization in bony defects is described, which offers significant potential in the evaluation of bone tissue engineering constructs.

  8. Development of an Alert System to Detect Drug Interactions with Herbal Supplements using Medical Record Data.

    PubMed

    Archer, Melissa; Proulx, Joshua; Shane-McWhorter, Laura; Bray, Bruce E; Zeng-Treitler, Qing

    2014-01-01

    While potential medication-to-medication interaction alerting engines exist in many clinical applications, few systems exist to automatically alert on potential medication to herbal supplement interactions. We have developed a preliminary knowledge base and rules alerting engine that detects 259 potential interactions between 9 supplements, 62 cardiac medications, and 19 drug classes. The rules engine takes into consideration 12 patient risk factors and 30 interaction warning signs to help determine which of three different alert levels to categorize each potential interaction. A formative evaluation was conducted with two clinicians to set initial thresholds for each alert level. Additional work is planned add more supplement interactions, risk factors, and warning signs as well as to continue to set and adjust the inputs and thresholds for each potential interaction.

  9. Compound cycle engine for helicopter application

    NASA Technical Reports Server (NTRS)

    Castor, Jere; Martin, John; Bradley, Curtiss

    1987-01-01

    The compound cycle engine (CCE) is a highly turbocharged, power-compounded, ultra-high-power-density, lightweight diesel engine. The turbomachinery is similar to a moderate-pressure-ratio, free-power-turbine gas turbine engine and the diesel core is high speed and a low compression ratio. This engine is considered a potential candidate for future military helicopter applications. Cycle thermodynamic specific fuel consumption (SFC) and engine weight analyses performed to establish general engine operating parameters and configurations are presented. An extensive performance and weight analysis based on a typical 2-hour helicopter (+30 minute reserve) mission determined final conceptual engine design. With this mission, CCE performance was compared to that of a contemporary gas turbine engine. The CCE had a 31 percent lower-fuel consumption and resulted in a 16 percent reduction in engine plus fuel and fuel tank weight. Design SFC of the CCE is 0.33 lb/hp-hr and installed wet weight is 0.43 lb/hp. The major technology development areas required for the CCE are identified and briefly discussed.

  10. Compound cycle engine for helicopter application

    NASA Technical Reports Server (NTRS)

    Castor, Jere G.

    1986-01-01

    The Compound Cycle Engine (CCE) is a highly turbocharged, power compounded, ultra-high power density, light-weight diesel engine. The turbomachinery is similar to a moderate pressure ratio, free power turbine engine and the diesel core is high speed and a low compression ratio. This engine is considered a potential candidate for future military light helicopter applications. This executive summary presents cycle thermodynamic (SFC) and engine weight analyses performed to establish general engine operating parameters and configuration. An extensive performance and weight analysis based on a typical two hour helicopter (+30 minute reserve) mission determined final conceptual engine design. With this mission, CCE performance was compared to that of a T-800 class gas turbine engine. The CCE had a 31% lower-fuel consumption and resulted in a 16% reduction in engine plus fuel and fuel tank weight. Design SFC of the CCE is 0.33 lb-HP-HR and installed wet weight is 0.43 lbs/HP. The major technology development areas required for the CCE are identified and briefly discussed.

  11. Annular Ion Engine Concept and Development Status

    NASA Technical Reports Server (NTRS)

    Patterson, Michael J.

    2016-01-01

    The Annular Ion Engine (AIE) concept represents an evolutionary development in gridded ion thruster technology with the potential for delivering revolutionary capabilities. It has this potential because the AIE concept: (a) enables scaling of ion thruster technology to high power at specific impulse (Isp) values of interest for near-term mission applications, 5000 sec; and (b) it enables an increase in both thrust density and thrust-to-power (FP) ratio exceeding conventional ion thrusters and other electric propulsion (EP) technology options, thereby yielding the highest performance over a broad range in Isp. The AIE concept represents a natural progression of gridded ion thruster technology beyond the capabilities embodied by NASAs Evolutionary Xenon Thruster (NEXT) [1]. The AIE would be appropriate for: (a) applications which require power levels exceeding NEXTs capabilities (up to about 14 kW [2]), with scalability potentially to 100s of kW; and/or (b) applications which require FP conditions exceeding NEXTs capabilities.

  12. Engineered Proteins: Redox Properties and Their Applications

    PubMed Central

    Prabhulkar, Shradha; Tian, Hui; Wang, Xiaotang; Zhu, Jun-Jie

    2012-01-01

    Abstract Oxidoreductases and metalloproteins, representing more than one third of all known proteins, serve as significant catalysts for numerous biological processes that involve electron transfers such as photosynthesis, respiration, metabolism, and molecular signaling. The functional properties of the oxidoreductases/metalloproteins are determined by the nature of their redox centers. Protein engineering is a powerful approach that is used to incorporate biological and abiological redox cofactors as well as novel enzymes and redox proteins with predictable structures and desirable functions for important biological and chemical applications. The methods of protein engineering, mainly rational design, directed evolution, protein surface modifications, and domain shuffling, have allowed the creation and study of a number of redox proteins. This review presents a selection of engineered redox proteins achieved through these methods, resulting in a manipulation in redox potentials, an increase in electron-transfer efficiency, and an expansion of native proteins by de novo design. Such engineered/modified redox proteins with desired properties have led to a broad spectrum of practical applications, ranging from biosensors, biofuel cells, to pharmaceuticals and hybrid catalysis. Glucose biosensors are one of the most successful products in enzyme electrochemistry, with reconstituted glucose oxidase achieving effective electrical communication with the sensor electrode; direct electron-transfer-type biofuel cells are developed to avoid thermodynamic loss and mediator leakage; and fusion proteins of P450s and redox partners make the biocatalytic generation of drug metabolites possible. In summary, this review includes the properties and applications of the engineered redox proteins as well as their significance and great potential in the exploration of bioelectrochemical sensing devices. Antioxid. Redox Signal. 17, 1796–1822. PMID:22435347

  13. NASA Applications and Lessons Learned in Reliability Engineering

    NASA Technical Reports Server (NTRS)

    Safie, Fayssal M.; Fuller, Raymond P.

    2011-01-01

    Since the Shuttle Challenger accident in 1986, communities across NASA have been developing and extensively using quantitative reliability and risk assessment methods in their decision making process. This paper discusses several reliability engineering applications that NASA has used over the year to support the design, development, and operation of critical space flight hardware. Specifically, the paper discusses several reliability engineering applications used by NASA in areas such as risk management, inspection policies, components upgrades, reliability growth, integrated failure analysis, and physics based probabilistic engineering analysis. In each of these areas, the paper provides a brief discussion of a case study to demonstrate the value added and the criticality of reliability engineering in supporting NASA project and program decisions to fly safely. Examples of these case studies discussed are reliability based life limit extension of Shuttle Space Main Engine (SSME) hardware, Reliability based inspection policies for Auxiliary Power Unit (APU) turbine disc, probabilistic structural engineering analysis for reliability prediction of the SSME alternate turbo-pump development, impact of ET foam reliability on the Space Shuttle System risk, and reliability based Space Shuttle upgrade for safety. Special attention is given in this paper to the physics based probabilistic engineering analysis applications and their critical role in evaluating the reliability of NASA development hardware including their potential use in a research and technology development environment.

  14. The Application of Hardware in the Loop Testing for Distributed Engine Control

    NASA Technical Reports Server (NTRS)

    Thomas, George L.; Culley, Dennis E.; Brand, Alex

    2016-01-01

    The essence of a distributed control system is the modular partitioning of control function across a hardware implementation. This type of control architecture requires embedding electronics in a multitude of control element nodes for the execution of those functions, and their integration as a unified system. As the field of distributed aeropropulsion control moves toward reality, questions about building and validating these systems remain. This paper focuses on the development of hardware-in-the-loop (HIL) test techniques for distributed aero engine control, and the application of HIL testing as it pertains to potential advanced engine control applications that may now be possible due to the intelligent capability embedded in the nodes.

  15. Potential Nano-Enabled Environmental Applications for Radionuclides

    EPA Pesticide Factsheets

    This document provides information about nanotechnology materials and processes that may be applicable when cleaning up radioactively contaminated sites or materials, and presents a snapshot of lessons learned in nano-science and engineering.

  16. Potential use of algae for heavy metal bioremediation, a critical review.

    PubMed

    Zeraatkar, Amin Keyvan; Ahmadzadeh, Hossein; Talebi, Ahmad Farhad; Moheimani, Navid R; McHenry, Mark P

    2016-10-01

    Algae have several industrial applications that can lower the cost of biofuel co-production. Among these co-production applications, environmental and wastewater bioremediation are increasingly important. Heavy metal pollution and its implications for public health and the environment have led to increased interest in developing environmental biotechnology approaches. We review the potential for algal biosorption and/or neutralization of the toxic effects of heavy metal ions, primarily focusing on their cellular structure, pretreatment, modification, as well as potential application of genetic engineering in biosorption performance. We evaluate pretreatment, immobilization, and factors affecting biosorption capacity, such as initial metal ion concentration, biomass concentration, initial pH, time, temperature, and interference of multi metal ions and introduce molecular tools to develop engineered algal strains with higher biosorption capacity and selectivity. We conclude that consideration of these parameters can lead to the development of low-cost micro and macroalgae cultivation with high bioremediation potential. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. [Fermentation production of microbial catalase and its application in textile industry].

    PubMed

    Zhang, Dongxu; Du, Guocheng; Chen, Jian

    2010-11-01

    Microbial catalase is an important industrial enzyme that catalyzes the decomposition of hydrogen peroxide to water and oxygen. This enzyme has great potential of application in food, textile and pharmaceutical industries. The production of microbial catalase has been significantly improved thanks to advances in bioprocess engineering and genetic engineering. In this paper, we review the progresses in fermentation production of microbial catalase and its application in textile industry. Among these progresses, we will highlight strain isolation, substrate and environment optimization, enzyme induction, construction of engineering strains and application process optimization. Meanwhile, we also address future research trends for microbial catalase production and its application in textile industry. Molecular modification (site-directed mutagenesis and directed revolution) will endue catalase with high pH and temperature stabilities. Improvement of catalase production, based on the understanding of induction mechanism and the process control of recombinant stain fermentation, will further accelerate the application of catalase in textile industry.

  18. The Development of Titanium Alloys for Application in the Space Shuttle Main Engine

    NASA Technical Reports Server (NTRS)

    Halchak, John A.; Jerman, Gregory A.; Zimmerman, Frank R.

    2010-01-01

    The high-strength-to-weight ratio of titanium alloys, particularly at cryogenic temperatures, make them attractive for application in rocket engines - offering the potential of superior performance while minimizing component weight. This was particularly attractive for rotating components, such as pump impellers, where titanium alloys presented the potential to achieve a major advance in rotational tip speed, with a reduction in stages and resultant saving in pump weight and complexity. The investigation into titanium alloys for application in cryogenic turbopumps began in the early 1960's. However, it was found that the reactivity of titanium limited applications and produced unique processing challenges. Specialized chemical compositions and processing techniques had to be developed. A substantial amount of material properties testing and trials in experimental turbopumps occurred, ultimately leading to application in the Space Shuttle Main Engine. One particular alloy stood out for use at liquid hydrogen temperatures, Ti-5Al-2.5Sn ELI. This alloy was employed for several critical components. This presentation deals with the development effort, the challenges that were encountered and operational experiences with Ti-5Al-2.5Sn ELI in the SSME.

  19. Precision Metabolic Engineering: the Design of Responsive, Selective, and Controllable Metabolic Systems

    PubMed Central

    McNerney, Monica P.; Watstein, Daniel M.; Styczynski, Mark P.

    2015-01-01

    Metabolic engineering is generally focused on static optimization of cells to maximize production of a desired product, though recently dynamic metabolic engineering has explored how metabolic programs can be varied over time to improve titer. However, these are not the only types of applications where metabolic engineering could make a significant impact. Here, we discuss a new conceptual framework, termed “precision metabolic engineering,” involving the design and engineering of systems that make different products in response to different signals. Rather than focusing on maximizing titer, these types of applications typically have three hallmarks: sensing signals that determine the desired metabolic target, completely directing metabolic flux in response to those signals, and producing sharp responses at specific signal thresholds. In this review, we will first discuss and provide examples of precision metabolic engineering. We will then discuss each of these hallmarks and identify which existing metabolic engineering methods can be applied to accomplish those tasks, as well as some of their shortcomings. Ultimately, precise control of metabolic systems has the potential to enable a host of new metabolic engineering and synthetic biology applications for any problem where flexibility of response to an external signal could be useful. PMID:26189665

  20. Exposure assessment and risk management of engineered nanoparticles: Investigation in semiconductor wafer processing

    NASA Astrophysics Data System (ADS)

    Shepard, Michele N.

    Engineered nanomaterials (ENMs) are currently used in hundreds of commercial products and industrial processes, with more applications being investigated. Nanomaterials have unique properties that differ from bulk materials. While these properties may enable technological advancements, the potential risks of ENMs to people and the environment are not yet fully understood. Certain low solubility nanoparticles are more toxic than their bulk material, such that existing occupational exposure limits may not be sufficiently protective for workers. Risk assessments are currently challenging due to gaps in data on the numerous emerging materials and applications as well as method uncertainties and limitations. Chemical mechanical planarization (CMP) processes with engineered nanoparticle abrasives are used for research and commercial manufacturing applications in the semiconductor and related industries. Despite growing use, no published studies addressed occupational exposures to nanoparticles associated with CMP or risk assessment and management practices for these scenarios. Additional studies are needed to evaluate potential sources of workplace exposure or emission, as well as to help test and refine assessment methods. This research was conducted to: identify the lifecycle stages and potential exposure sources for ENMs in CMP processes; characterize worker exposure; determine recommended engineering controls and compare risk assessment models. The study included workplace air and surface sampling and an evaluation of qualitative risk banding approaches. Exposure assessment results indicated the potential for worker contact with ENMs on workplace surfaces but did not identify nanoparticles readily dispersed in air during work tasks. Some increases in respirable particle concentrations were identified, but not consistently. Measured aerosol concentrations by number and mass were well below current reference values for poorly soluble low toxicity nanoparticles. From application and evaluation of qualitative risk assessment approaches, differences in control banding models and results were identified, although output generally agreed with conclusions from air sampling as to whether an upgrade in site engineering controls was recommended. This research helped to improve understanding of potential worker exposures to ENMs in CMP processes, as well as the methods for risk assessment and management of metal oxide nanoparticles in occupational environments.

  1. A study of the Armstrong Whitworth swing beam engine for automotive application

    NASA Technical Reports Server (NTRS)

    1983-01-01

    The introduction of ceramics to those parts suffering high thermal loading was successfully demonstrated, and there is no question that the 100 kw (134 hp) naturally aspirated engine of the future will be developed to produce up to 300 kw (402 hp) by the application of turbocharging or its equivalent. However, at the 60 - 80 kw (80 - 107 hp) size needed for the economic automotive engine, scaling down the 300 kw (402 hp) is beset by the laws of scale. The conventional four stroke diesel was not shown to be successful at the small high speed engine size. The opposed piston two stroke engine does not suffer the same laws of scale and engines in the low power range have already been marketed successfully. The half liter/cylinder Armstrong Whitworth Swing Beam Engine is the latest to be designed with the automotive market in mind. Its low noise structure and balanced linkage system coupled with advantages for easy start and potential use of low grade fuels, derived from its variable compression ratio and slow piston motion, qualifies it for the application.

  2. J85 Rejuvenation Through Technology Insertion

    DTIC Science & Technology

    2000-10-01

    and Sabre 75 business addition to military production, the J85 was jets . Number Model Produced Aircraft Type(s) Engine Type Thrust (lbs) J85-GE-4 740...REJUVENATION THROUGH TECHNOLOGY INSERTION T.A. Brisken, P.N. Howell, A.C. Ewing Military Engines Operation GE Aircraft Engines 1 Neumann Way Cincinnati...OH 45215, USA Summary thrust to weight ratio turbojet engines with potential application to early cruise missiles and drones. The history of the

  3. Development potential of Intermittent Combustion (I.C.) aircraft engines for commuter transport applications

    NASA Technical Reports Server (NTRS)

    Willis, E. A.

    1982-01-01

    An update on general aviation (g/a) and commuter aircraft propulsion research effort is reviewed. The following topics are discussed: on several advanced intermittent combustion engines emphasizing lightweight diesels and rotary stratified charge engines. The current state-of-the-art is evaluated for lightweight, aircraft suitable versions of each engine. This information is used to project the engine characteristics that can be expected on near-term and long-term time horizons. The key enabling technology requirements are identified for each engine on the long-term time horizon.

  4. Natural gas applications for hybrid vehicles. Final report, October 1992-July 1993

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bentley, J.M.

    1993-08-01

    Hybrid vehicle technology holds the potential for improved efficiency and emissions compared with internal combustion (IC) engines and improved range and refueling convenience over electric vehicles. This study evaluated the potential for using natural gas as a hybrid vehicle fuel. Potential regulatory and market drivers were evaluated for hybrids generally and natural gas hybrids in specific. Heat engine options and other configuration issues were investigated to determine efficiency, emissions or other benefits of light- and heavy-duty hybrids. Several hybrid vehicle configurations were evaluated to determine the specific packaging attributes of natural gas in a hybrid configuration. Generally, conventional IC enginesmore » appear adequate for most emissions-sensitive hybrid applications with no great advantage being gained from using turbines or other more advanced heat engines. The largest technology barrier to a near-term hybrid is the weight of available or near-term batteries. Smaller, light-duty hybrid vehicles will be more sensitive to this weight handicap than larger vehicles such as the urban transit bus.« less

  5. Adipose-Derived Stem Cells for Tissue Engineering and Regenerative Medicine Applications

    PubMed Central

    Dai, Ru; Wang, Zongjie; Samanipour, Roya; Koo, Kyo-in; Kim, Keekyoung

    2016-01-01

    Adipose-derived stem cells (ASCs) are a mesenchymal stem cell source with properties of self-renewal and multipotential differentiation. Compared to bone marrow-derived stem cells (BMSCs), ASCs can be derived from more sources and are harvested more easily. Three-dimensional (3D) tissue engineering scaffolds are better able to mimic the in vivo cellular microenvironment, which benefits the localization, attachment, proliferation, and differentiation of ASCs. Therefore, tissue-engineered ASCs are recognized as an attractive substitute for tissue and organ transplantation. In this paper, we review the characteristics of ASCs, as well as the biomaterials and tissue engineering methods used to proliferate and differentiate ASCs in a 3D environment. Clinical applications of tissue-engineered ASCs are also discussed to reveal the potential and feasibility of using tissue-engineered ASCs in regenerative medicine. PMID:27057174

  6. Enabling functional genomics with genome engineering

    PubMed Central

    Hilton, Isaac B.; Gersbach, Charles A.

    2015-01-01

    Advances in genome engineering technologies have made the precise control over genome sequence and regulation possible across a variety of disciplines. These tools can expand our understanding of fundamental biological processes and create new opportunities for therapeutic designs. The rapid evolution of these methods has also catalyzed a new era of genomics that includes multiple approaches to functionally characterize and manipulate the regulation of genomic information. Here, we review the recent advances of the most widely adopted genome engineering platforms and their application to functional genomics. This includes engineered zinc finger proteins, TALEs/TALENs, and the CRISPR/Cas9 system as nucleases for genome editing, transcription factors for epigenome editing, and other emerging applications. We also present current and potential future applications of these tools, as well as their current limitations and areas for future advances. PMID:26430154

  7. Site-Specific Genome Engineering in Human Pluripotent Stem Cells.

    PubMed

    Merkert, Sylvia; Martin, Ulrich

    2016-06-24

    The possibility to generate patient-specific induced pluripotent stem cells (iPSCs) offers an unprecedented potential of applications in clinical therapy and medical research. Human iPSCs and their differentiated derivatives are tools for diseases modelling, drug discovery, safety pharmacology, and toxicology. Moreover, they allow for the engineering of bioartificial tissue and are promising candidates for cellular therapies. For many of these applications, the ability to genetically modify pluripotent stem cells (PSCs) is indispensable, but efficient site-specific and safe technologies for genetic engineering of PSCs were developed only recently. By now, customized engineered nucleases provide excellent tools for targeted genome editing, opening new perspectives for biomedical research and cellular therapies.

  8. Genetic Engineering and Crop Production.

    ERIC Educational Resources Information Center

    Jones, Helen C.; Frost, S.

    1991-01-01

    With a spotlight upon current agricultural difficulties and environmental dilemmas, this paper considers both the extant and potential applications of genetic engineering with respect to crop production. The nonagricultural factors most likely to sway the impact of this emergent technology upon future crop production are illustrated. (JJK)

  9. Pharmaceutical and biomedical potential of surface engineered dendrimers.

    PubMed

    Satija, Jitendra; Gupta, Umesh; Jain, Narendra Kumar

    2007-01-01

    Dendrimers are hyperbranched, globular, monodisperse, nanometric polymeric architecture, having definite molecular weight, shape, and size (which make these an inimitable and optimum carrier molecule in pharmaceutical field). Dendritic architecture is having immense potential over the other carrier systems, particularly in the field of drug delivery because of their unique properties, such as structural uniformity, high purity, efficient membrane transport, high drug pay load, targeting potential, and good colloidal, biological, and shelf stability. Despite their enormous applicability in different areas, the inherent cytotoxicity, reticuloendothelial system (RES) uptake, drug leakage, immunogenicity, and hemolytic toxicity restricted their use in clinical applications, which is primarily associated with cationic charge present on the periphery due to amine groups. To overcome this toxic nature of dendrimers, some new types of nontoxic, biocompatible, and biodegradable dendrimers have been developed (e.g., polyester dendrimer, citric acid dendrimer, arginine dendrimer, carbohydrate dendrimers, etc.). The surface engineering of parent dendrimers is graceful and convenient strategy, which not only shields the positive charge to make this carrier more biomimetic but also improves the physicochemical and biological behavior of parent dendrimers. Thus, surface modification chemistry of parent dendrimers holds promise in pharmaceutical applications (such as solubilization, improved drug encapsulation, enhanced gene transfection, sustained and controlled drug release, intracellular targeting) and in the diagnostic field. Development of multifunctional dendrimer holds greater promise toward the biomedical applications because a number of targeting ligands determine specificity in the same manner as another type of group would secure stability in biological milieu and prolonged circulation, whereas others facilitate their transport through cell membranes. Therefore, as a consequence of ideal hyperbranched architecture and the biocompatible nature of engineered dendrimers, their utilization has been included in the scope of this review, which focuses on current surface alteration strategies of dendrimers for their potential use in drug delivery and explains the possible beneficial applications of these engineered dendrimers in the biomedical field.

  10. The potential for CMCs to replace superalloys in engine exhaust ducts

    NASA Astrophysics Data System (ADS)

    Roth, Richard; Clark, Joel P.; Field, Frank R.

    1994-01-01

    The Materials Systems Laboratory at the Massachusetts Institute of Technology has conducted research to develop decision tools that can facilitate materials selection and provide a deeper understanding of the design tradeoffs that occur when choosing among advanced aerospace materials for high-temperature applications. As an illustration of the use of these tools, this paper describes research done to evaluate the material alternatives currently under consideration for exhaust ducts in aircraft gas turbine engines. Although nickel-based superalloys currently prevail for this application, the increasing temperatures of modern engines are necessitating the usage of higher temperature materials.

  11. Space shuttle main engine anomaly data and inductive knowledge based systems: Automated corporate expertise

    NASA Technical Reports Server (NTRS)

    Modesitt, Kenneth L.

    1987-01-01

    Progress is reported on the development of SCOTTY, an expert knowledge-based system to automate the analysis procedure following test firings of the Space Shuttle Main Engine (SSME). The integration of a large-scale relational data base system, a computer graphics interface for experts and end-user engineers, potential extension of the system to flight engines, application of the system for training of newly-hired engineers, technology transfer to other engines, and the essential qualities of good software engineering practices for building expert knowledge-based systems are among the topics discussed.

  12. Free-piston Stirling Engine system considerations for various space power applications

    NASA Technical Reports Server (NTRS)

    Dochat, George R.; Dhar, Manmohan

    1991-01-01

    Free-Piston Stirling Engines (FPSE) have the potential to provide high reliability, long life, and efficient operation. Therefore, they are excellent candidates for the dynamic power conversion module of a space-based, power-generating system. FPSE can be coupled with many potential heat sources (radioisotope, solar, or nuclear reactor), various heat input systems (pumped loop, heat pipe), heat rejection (pumped loop or heat pipe), and various power management and distribution systems (ac, dc, high or low voltage, and fixed or variable load). This paper reviews potential space missions that can be met using free-piston Stirling engines and discusses options of various system integration approaches. This paper briefly outlines the program and recent progress.

  13. Applications of spaceborne laser ranger on EOS

    NASA Technical Reports Server (NTRS)

    Degnan, John J.; Cohen, Steven C.

    1988-01-01

    An account is given of the design concept and potential applications in science and engineering of the spaceborne laser ranging and altimeter apparatus employed by the Geodynamics Laser Ranging System; this is scheduled for 1997 launch as part of the multiple-satellite Earth Observing System. In the retrograding mode for geodynamics, the system will use a Nd:YAG laser's green and UV output for distance determination to ground retroreflectors. Engineering applications encompass land management and long-term ground stability studies relevant to nuclear power plant, pipeline, and aqueduct locations.

  14. Neural tissue engineering: Bioresponsive nanoscaffolds using engineered self-assembling peptides.

    PubMed

    Koss, K M; Unsworth, L D

    2016-10-15

    Rescuing or repairing neural tissues is of utmost importance to the patient's quality of life after an injury. To remedy this, many novel biomaterials are being developed that are, ideally, non-invasive and directly facilitate neural wound healing. As such, this review surveys the recent approaches and applications of self-assembling peptides and peptide amphiphiles, for building multi-faceted nanoscaffolds for direct application to neural injury. Specifically, methods enabling cellular interactions with the nanoscaffold and controlling the release of bioactive molecules from the nanoscaffold for the express purpose of directing endogenous cells in damaged or diseased neural tissues is presented. An extensive overview of recently derived self-assembling peptide-based materials and their use as neural nanoscaffolds is presented. In addition, an overview of potential bioactive peptides and ligands that could be used to direct behaviour of endogenous cells are categorized with their biological effects. Finally, a number of neurotrophic and anti-inflammatory drugs are described and discussed. Smaller therapeutic molecules are emphasized, as they are thought to be able to have less potential effect on the overall peptide self-assembly mechanism. Options for potential nanoscaffolds and drug delivery systems are suggested. Self-assembling nanoscaffolds have many inherent properties making them amenable to tissue engineering applications: ease of synthesis, ease of customization with bioactive moieties, and amenable for in situ nanoscaffold formation. The combination of the existing knowledge on bioactive motifs for neural engineering and the self-assembling propensity of peptides is discussed in specific reference to neural tissue engineering. Copyright © 2016. Published by Elsevier Ltd.

  15. Precision metabolic engineering: The design of responsive, selective, and controllable metabolic systems.

    PubMed

    McNerney, Monica P; Watstein, Daniel M; Styczynski, Mark P

    2015-09-01

    Metabolic engineering is generally focused on static optimization of cells to maximize production of a desired product, though recently dynamic metabolic engineering has explored how metabolic programs can be varied over time to improve titer. However, these are not the only types of applications where metabolic engineering could make a significant impact. Here, we discuss a new conceptual framework, termed "precision metabolic engineering," involving the design and engineering of systems that make different products in response to different signals. Rather than focusing on maximizing titer, these types of applications typically have three hallmarks: sensing signals that determine the desired metabolic target, completely directing metabolic flux in response to those signals, and producing sharp responses at specific signal thresholds. In this review, we will first discuss and provide examples of precision metabolic engineering. We will then discuss each of these hallmarks and identify which existing metabolic engineering methods can be applied to accomplish those tasks, as well as some of their shortcomings. Ultimately, precise control of metabolic systems has the potential to enable a host of new metabolic engineering and synthetic biology applications for any problem where flexibility of response to an external signal could be useful. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  16. Nanofibers and their applications in tissue engineering

    PubMed Central

    Vasita, Rajesh; Katti, Dhirendra S

    2006-01-01

    Developing scaffolds that mimic the architecture of tissue at the nanoscale is one of the major challenges in the field of tissue engineering. The development of nanofibers has greatly enhanced the scope for fabricating scaffolds that can potentially meet this challenge. Currently, there are three techniques available for the synthesis of nanofibers: electrospinning, self-assembly, and phase separation. Of these techniques, electrospinning is the most widely studied technique and has also demonstrated the most promising results in terms of tissue engineering applications. The availability of a wide range of natural and synthetic biomaterials has broadened the scope for development of nanofibrous scaffolds, especially using the electrospinning technique. The three dimensional synthetic biodegradable scaffolds designed using nanofibers serve as an excellent framework for cell adhesion, proliferation, and differentiation. Therefore, nanofibers, irrespective of their method of synthesis, have been used as scaffolds for musculoskeletal tissue engineering (including bone, cartilage, ligament, and skeletal muscle), skin tissue engineering, vascular tissue engineering, neural tissue engineering, and as carriers for the controlled delivery of drugs, proteins, and DNA. This review summarizes the currently available techniques for nanofiber synthesis and discusses the use of nanofibers in tissue engineering and drug delivery applications. PMID:17722259

  17. ENGINEERING BULLETIN: COMPOSTING

    EPA Science Inventory

    Composting is an emerging ex situ biological technology that is potentially applicable to nonvolatile and semivolatile organic compounds (SVOCs) in soils. It has been applied to polycyclic aromatic hydrocarbons (PAHs) and explosives. It has been found to be potentially effectiv...

  18. Group Projects and the Computer Science Curriculum

    ERIC Educational Resources Information Center

    Joy, Mike

    2005-01-01

    Group projects in computer science are normally delivered with reference to good software engineering practice. The discipline of software engineering is rapidly evolving, and the application of the latest 'agile techniques' to group projects causes a potential conflict with constraints imposed by regulating bodies on the computer science…

  19. Study of unconventional aircraft engines designed for low energy consumption

    NASA Technical Reports Server (NTRS)

    Gray, D. E.

    1976-01-01

    Declining U.S. oil reserves and escalating energy costs underline the need for reducing fuel consumption in aircraft engines. The most promising unconventional aircraft engines based on their potential for fuel savings and improved economics are identified. The engines installed in both a long-range and medium-range aircraft were evaluated. Projected technology advances are identified and evaluated for their state-of-readiness for application to a commercial transport. Programs are recommended for developing the necessary technology.

  20. A conceptual study of the potential for automotive-derived and free-piston Stirling engines in 30- to 400-kilowatt stationary power applications

    NASA Technical Reports Server (NTRS)

    Vatsky, A.; Chen, H. S.; Dineen, J.

    1982-01-01

    The technical feasibility of applying automotive-derived kinematic and free-piston Stirling engine concepts for stationary applications was explored. Automotive-derived engines offer cost advantages by providing a mature and developd engine technology base with downrating and parts commonality options for specific applications. Two engine sizes (30 and 400 kW), two Stirling engine configurations (kinematic and free-piston), and two output systems (crankshaft and hydraulic pump) were studied. The study includes the influences of using either hydrogen or helium as the working gas. The first kinematic configuration selects an existing Stirling engine design from an automotive application and adapts it to stationary requirements. A 50,000-hour life requirement was established by downrating the engine to 40 kW and reducing auxiliary loads. Efficiency improvements were gained by selective material and geometric variations and peak brake efficiency of 36.8 percent using helium gas was achieved. The second design was a four-cylinder, 400 kW engine, utilizing a new output drive system known as the z-crank, which provides lower friction losses and variable stroke power control. Three different material and working gas combinations were considered. Brake efficiency levels varied from 40.5 percent to 45.6 percent. A 37.5 kW single-cycle, free-piston hydraulic output design was generated by scaling one cylinder of the original automotive engine and mating it to a counterbalanced reciprocal hydraulic pump. Metallic diaphragms were utilized to transmit power.

  1. A conceptual study of the potential for automotive-derived and free-piston Stirling engines in 30- to 400-kilowatt stationary power applications

    NASA Astrophysics Data System (ADS)

    Vatsky, A.; Chen, H. S.; Dineen, J.

    1982-05-01

    The technical feasibility of applying automotive-derived kinematic and free-piston Stirling engine concepts for stationary applications was explored. Automotive-derived engines offer cost advantages by providing a mature and developd engine technology base with downrating and parts commonality options for specific applications. Two engine sizes (30 and 400 kW), two Stirling engine configurations (kinematic and free-piston), and two output systems (crankshaft and hydraulic pump) were studied. The study includes the influences of using either hydrogen or helium as the working gas. The first kinematic configuration selects an existing Stirling engine design from an automotive application and adapts it to stationary requirements. A 50,000-hour life requirement was established by downrating the engine to 40 kW and reducing auxiliary loads. Efficiency improvements were gained by selective material and geometric variations and peak brake efficiency of 36.8 percent using helium gas was achieved. The second design was a four-cylinder, 400 kW engine, utilizing a new output drive system known as the z-crank, which provides lower friction losses and variable stroke power control. Three different material and working gas combinations were considered. Brake efficiency levels varied from 40.5 percent to 45.6 percent. A 37.5 kW single-cycle, free-piston hydraulic output design was generated by scaling one cylinder of the original automotive engine and mating it to a counterbalanced reciprocal hydraulic pump. Metallic diaphragms were utilized to transmit power.

  2. Potential Information and Decision Support System Applications for a Civil Engineering RED HORSE Squadron.

    DTIC Science & Technology

    1987-09-01

    APPLICATIONS FOR A CIVIL ENGINEERILaG RED HORSE SQUADRON THESIS Arvil E. White III Captain, USAF AFIT/GE:4/LSM/87S-27 .... DEPARTMENT OF THE AIR FORCE...DT1TO-SJAN 0 419880 POTENTIAL INFORMATION AND DECISION SUPPORT SYSTEM APPLICATIONS FOR A CIVIL ENGINEERILiG RED HORSE SQUADRON IAooession For THESIS NI R...INFORMATION AND DECISION SUPPORT SYSTrEM APPLICATIONS FOR A CIVIL ENGINEERINGX :.. 4. RED HORSE SQUADRON - THESIS -4 Presented to the Faculty of the

  3. Enhancing Systems Engineering Education Through Case Study Writing

    NASA Technical Reports Server (NTRS)

    Stevens, Jennifer Stenger

    2016-01-01

    Developing and refining methods for teaching systems engineering is part of Systems Engineering grand challenges and agenda for research in the SE research community. Retention of systems engineering knowledge is a growing concern in the United States as the baby boom generation continues to retire and the faster pace of technology development does not allow for younger generations to gain experiential knowledge through years of practice. Government agencies, including the National Aeronautics and Space Administration (NASA), develop their own curricula and SE leadership development programs to "grow their own" systems engineers. Marshall Space Flight Center (MSFC) conducts its own Center-focused Marshall Systems Engineering Leadership Development Program (MSELDP), a competitive program consisting of coursework, a guest lecture series, and a rotational assignment into an unfamiliar organization engaged in systems engineering. Independently, MSFC developed two courses to address knowledge retention and sharing concerns: Real World Marshall Mission Success course and its Case Study Writers Workshop and Writers Experience. Teaching case study writing and leading students through a hands-on experience at writing a case study on an SE topic can enhance SE training and has the potential to accelerate the transfer of experiential knowledge. This paper is an overview of the pilot experiences with teaching case study writing, its application in case study-based learning, and identifies potential areas of research and application for case study writing in systems engineering education.

  4. Advanced Control Considerations for Turbofan Engine Design

    NASA Technical Reports Server (NTRS)

    Connolly, Joseph W.; Csank, Jeffrey T.; Chicatelli, Amy

    2016-01-01

    This paper covers the application of a model-based engine control (MBEC) methodology featuring a self tuning on-board model for an aircraft turbofan engine simulation. The nonlinear engine model is capable of modeling realistic engine performance, allowing for a verification of the advanced control methodology over a wide range of operating points and life cycle conditions. The on-board model is a piece-wise linear model derived from the nonlinear engine model and updated using an optimal tuner Kalman Filter estimation routine, which enables the on-board model to self-tune to account for engine performance variations. MBEC is used here to show how advanced control architectures can improve efficiency during the design phase of a turbofan engine by reducing conservative operability margins. The operability margins that can be reduced, such as stall margin, can expand the engine design space and offer potential for efficiency improvements. Application of MBEC architecture to a nonlinear engine simulation is shown to reduce the thrust specific fuel consumption by approximately 1% over the baseline design, while maintaining safe operation of the engine across the flight envelope.

  5. System Integration - A Major Step toward Lab on a Chip

    PubMed Central

    2011-01-01

    Microfluidics holds great promise to revolutionize various areas of biological engineering, such as single cell analysis, environmental monitoring, regenerative medicine, and point-of-care diagnostics. Despite the fact that intensive efforts have been devoted into the field in the past decades, microfluidics has not yet been adopted widely. It is increasingly realized that an effective system integration strategy that is low cost and broadly applicable to various biological engineering situations is required to fully realize the potential of microfluidics. In this article, we review several promising system integration approaches for microfluidics and discuss their advantages, limitations, and applications. Future advancements of these microfluidic strategies will lead toward translational lab-on-a-chip systems for a wide spectrum of biological engineering applications. PMID:21612614

  6. Human adipose-derived stem cells: definition, isolation, tissue-engineering applications.

    PubMed

    Nae, S; Bordeianu, I; Stăncioiu, A T; Antohi, N

    2013-01-01

    Recent researches have demonstrated that the most effective repair system of the body is represented by stem cells - unspecialized cells, capable of self-renewal through successive mitoses, which have also the ability to transform into different cell types through differentiation. The discovery of adult stem cells represented an important step in regenerative medicine because they no longer raises ethical or legal issues and are more accessible. Only in 2002, stem cells isolated from adipose tissue were described as multipotent stem cells. Adipose tissue stem cells benefits in tissue engineering and regenerative medicine are numerous. Development of adipose tissue engineering techniques offers a great potential in surpassing the existing limits faced by the classical approaches used in plastic and reconstructive surgery. Adipose tissue engineering clinical applications are wide and varied, including reconstructive, corrective and cosmetic procedures. Nowadays, adipose tissue engineering is a fast developing field, both in terms of fundamental researches and medical applications, addressing issues related to current clinical pathology or trauma management of soft tissue injuries in different body locations.

  7. Microcomputed Tomography Characterization of Neovascularization in Bone Tissue Engineering Applications

    PubMed Central

    Young, Simon; Kretlow, James D.; Nguyen, Charles; Bashoura, Alex G.; Baggett, L. Scott; Jansen, John A.; Wong, Mark

    2008-01-01

    Abstract Vasculogenesis and angiogenesis have been studied for decades using numerous in vitro and in vivo systems, fulfilling the need to elucidate the mechanisms involved in these processes and to test potential therapeutic agents that inhibit or promote neovascularization. Bone tissue engineering in particular has benefited from the application of proangiogenic strategies, considering the need for an adequate vascular supply during healing and the challenges associated with the vascularization of scaffolds implanted in vivo. Conventional methods of assessing the in vivo angiogenic response to tissue-engineered constructs tend to rely on a two-dimensional assessment of microvessel density within representative histological sections without elaboration of the true vascular tree. The introduction of microcomputed tomography (micro-CT) has recently allowed investigators to obtain a diverse range of high-resolution, three-dimensional characterization of structures, including renal, coronary, and hepatic vascular networks, as well as bone formation within healing defects. To date, few studies have utilized micro-CT to study the vascular response to an implanted tissue engineering scaffold. In this paper, conventional in vitro and in vivo models for studying angiogenesis will be discussed, followed by recent developments in the use of micro-CT for vessel imaging in bone tissue engineering research. A new study demonstrating the potential of contrast-enhanced micro-CT for the evaluation of in vivo neovascularization in bony defects is described, which offers significant potential in the evaluation of bone tissue engineering constructs. PMID:18657028

  8. Numerical method to determine mechanical parameters of engineering design in rock masses.

    PubMed

    Xue, Ting-He; Xiang, Yi-Qiang; Guo, Fa-Zhong

    2004-07-01

    This paper proposes a new continuity model for engineering in rock masses and a new schematic method for reporting the engineering of rock continuity. This method can be used to evaluate the mechanics of every kind of medium; and is a new way to determine the mechanical parameters used in engineering design in rock masses. In the numerical simulation, the experimental parameters of intact rock were combined with the structural properties of field rock. The experimental results for orthogonally-jointed rock are given. The results included the curves of the stress-strain relationship of some rock masses, the curve of the relationship between the dimension Delta and the uniaxial pressure-resistant strength sc of these rock masses, and pictures of the destructive procedure of some rock masses in uniaxial or triaxial tests, etc. Application of the method to engineering design in rock masses showed the potential of its application to engineering practice.

  9. Ramgen Power Systems-Supersonic Component Technology for Military Engine Applications

    DTIC Science & Technology

    2006-11-01

    turbine efficiency power (kW) LHV efficiency HHV efficiency notes **Current Design Point 0.45 1700 1013 84.4% 220.1 35.4% 31.8% - Rampressor...tor (such as a standalone power-only mode device), or to a fuel cell in a hybrid configuration. This paper presents the development of the RPS gas...turbine technology and potential applications to the two specific engine cycle configurations, i.e., an indirect fuel cell / RPS turbine hybrid-cycle

  10. In vitro dosimetry modeling will be a critical step toward efficient assessment of engineered nanomaterials for environmental health and safety

    EPA Science Inventory

    Presentation Description: The development and application of engineered nanomaterials (ENM) into commercial and consumer products is far outpacing the ability of traditional approaches to evaluate the potential implications for environmental health and safety. This problem recen...

  11. Engaging Robots: Innovative Outreach for Attracting Cybernetics Students

    ERIC Educational Resources Information Center

    Mitchell, R.; Warwick, K.; Browne, W. N.; Gasson, M. N.; Wyatt, J.

    2010-01-01

    Cybernetics is a broad subject, encompassing many aspects of electrical, electronic, and computer engineering, which suffers from a lack of understanding on the part of potential applicants and teachers when recruiting students. However, once the engineering values, fascinating science, and pathways to rewarding, diverse careers are communicated,…

  12. Integrating interface slicing into software engineering processes

    NASA Technical Reports Server (NTRS)

    Beck, Jon

    1993-01-01

    Interface slicing is a tool which was developed to facilitate software engineering. As previously presented, it was described in terms of its techniques and mechanisms. The integration of interface slicing into specific software engineering activities is considered by discussing a number of potential applications of interface slicing. The applications discussed specifically address the problems, issues, or concerns raised in a previous project. Because a complete interface slicer is still under development, these applications must be phrased in future tenses. Nonetheless, the interface slicing techniques which were presented can be implemented using current compiler and static analysis technology. Whether implemented as a standalone tool or as a module in an integrated development or reverse engineering environment, they require analysis no more complex than that required for current system development environments. By contrast, conventional slicing is a methodology which, while showing much promise and intuitive appeal, has yet to be fully implemented in a production language environment despite 12 years of development.

  13. Enabling functional genomics with genome engineering.

    PubMed

    Hilton, Isaac B; Gersbach, Charles A

    2015-10-01

    Advances in genome engineering technologies have made the precise control over genome sequence and regulation possible across a variety of disciplines. These tools can expand our understanding of fundamental biological processes and create new opportunities for therapeutic designs. The rapid evolution of these methods has also catalyzed a new era of genomics that includes multiple approaches to functionally characterize and manipulate the regulation of genomic information. Here, we review the recent advances of the most widely adopted genome engineering platforms and their application to functional genomics. This includes engineered zinc finger proteins, TALEs/TALENs, and the CRISPR/Cas9 system as nucleases for genome editing, transcription factors for epigenome editing, and other emerging applications. We also present current and potential future applications of these tools, as well as their current limitations and areas for future advances. © 2015 Hilton and Gersbach; Published by Cold Spring Harbor Laboratory Press.

  14. Concept definition study of small Brayton cycle engines for dispersed solar electric power systems

    NASA Technical Reports Server (NTRS)

    Six, L. D.; Ashe, T. L.; Dobler, F. X.; Elkins, R. T.

    1980-01-01

    Three first-generation Brayton cycle engine types were studied for solar application: a near-term open cycle (configuration A), a near-term closed cycle (configuration B), and a longer-term open cycle (configuration C). A parametric performance analysis was carried out to select engine designs for the three configurations. The interface requirements for the Brayton cycle engine/generator and solar receivers were determined. A technology assessment was then carried out to define production costs, durability, and growth potential for the selected engine types.

  15. Potential Industrial Applications of the One Atmosphere Uniform Glow Discharge Plasma (OAUGDP) Operating in Ambient Air

    NASA Astrophysics Data System (ADS)

    Reece Roth, J.

    2004-11-01

    The majority of industrial plasma processing with glow discharges has been conducted at pressures below 10 torr. This tends to limit applications to high value workpieces as a result of the high capital cost of vacuum systems and the production constraints of batch processing. It has long been recognized that glow discharge plasmas would play a much larger industrial role if they could be generated at one atmosphere. The One Atmosphere Uniform Glow Discharge Plasma (OAUGDP), developed at the University of Tennessee's Plasma Sciences Laboratory, is a non-thermal RF plasma operating on displacement currents with the time-resolved characteristics of a classical low pressure DC normal glow discharge. As a glow discharge, the OAUGDP operates with maximum electrical efficiency at the Stoletow point, where the energy input per ion-electron pair is a minimum [1, 2]. Several interdisciplinary teams have investigated potential applications of the OAUGDP. These teams included collaborators from the UTK Textiles and Nonwovens Development Center (TANDEC), and the Departments of Electrical and Computer Engineering, Microbiology, and Food Science and Technology, as well as the NASA Langley Research Center. The potential applications of the OAUGDP have all been at one atmosphere and room temperature, using air as the working gas. These applications include sterilizing medical and dental equipment; sterilizable air filters to deal with the "sick building syndrome"; removal of soot from Diesel engine exhaust; subsonic plasma aerodynamic effects, including flow re-attachment to airfoils and boundary layer modification; electrohydrodynamic (EDH) flow control of working gases; increasing the surface energy of materials; improving the adhesion of paints and electroplated layers: improving the wettability and wickability of fabrics; stripping of photoresist; and plasma deposition and directional etching of potential microelectronic relevance. [1] J. R. Roth, Industrial Plasma Engineering: Volume I, Principles. Institute of Physics Publishing, Bristol and Philadelphia 1995, ISBN 0-7503-0318-2. [2] Roth, J. R. Industrial Plasma Engineering: Volume II Applications to Nonthermal Plasma Processing Institute of Physics Publishing, Bristol and Philadelphia. 2001, ISBN 0-7503-0545-2.

  16. Engineering the Bacterial Microcompartment Domain for Molecular Scaffolding Applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Young, Eric J.; Burton, Rodney; Mahalik, Jyoti P.

    As synthetic biology advances the intricacy of engineered biological systems, the importance of spatial organization within the cellular environment must not be marginalized. Increasingly, biological engineers are investigating means to control spatial organization within the cell, mimicking strategies used by natural pathways to increase flux and reduce cross-talk. A modular platform for constructing a diverse set of defined, programmable architectures would greatly assist in improving yields from introduced metabolic pathways and increasing insulation of other heterologous systems. Here, we review recent research on the shell proteins of bacterial microcompartments and discuss their potential application as “building blocks” for a rangemore » of customized intracellular scaffolds. As a result, we summarize the state of knowledge on the self-assembly of BMC shell proteins and discuss future avenues of research that will be important to realize the potential of BMC shell proteins as predictively assembling and programmable biological materials for bioengineering.« less

  17. Engineering the Bacterial Microcompartment Domain for Molecular Scaffolding Applications

    DOE PAGES

    Young, Eric J.; Burton, Rodney; Mahalik, Jyoti P.; ...

    2017-07-31

    As synthetic biology advances the intricacy of engineered biological systems, the importance of spatial organization within the cellular environment must not be marginalized. Increasingly, biological engineers are investigating means to control spatial organization within the cell, mimicking strategies used by natural pathways to increase flux and reduce cross-talk. A modular platform for constructing a diverse set of defined, programmable architectures would greatly assist in improving yields from introduced metabolic pathways and increasing insulation of other heterologous systems. Here, we review recent research on the shell proteins of bacterial microcompartments and discuss their potential application as “building blocks” for a rangemore » of customized intracellular scaffolds. As a result, we summarize the state of knowledge on the self-assembly of BMC shell proteins and discuss future avenues of research that will be important to realize the potential of BMC shell proteins as predictively assembling and programmable biological materials for bioengineering.« less

  18. Mesenchymal stem cell-mediated cancer therapy: A dual-targeted strategy of personalized medicine

    PubMed Central

    Sun, Xu-Yong; Nong, Jiang; Qin, Ke; Warnock, Garth L; Dai, Long-Jun

    2011-01-01

    Cancer remains one of the leading causes of mortality and morbidity throughout the world. To a significant extent, current conventional cancer therapies are symptomatic and passive in nature. The major obstacle to the development of effective cancer therapy is believed to be the absence of sufficient specificity. Since the discovery of the tumor-oriented homing capacity of mesenchymal stem cells (MSCs), the application of specific anticancer gene-engineered MSCs has held great potential for cancer therapies. The dual-targeted strategy is based on MSCs’ capacity of tumor-directed migration and incorporation and in situ expression of tumor-specific anticancer genes. With the aim of translating bench work into meaningful clinical applications, we describe the tumor tropism of MSCs and their use as therapeutic vehicles, the dual-targeted anticancer potential of engineered MSCs and a putative personalized strategy with anticancer gene-engineered MSCs. PMID:22180830

  19. Engineering the Bacterial Microcompartment Domain for Molecular Scaffolding Applications

    PubMed Central

    Young, Eric J.; Burton, Rodney; Mahalik, Jyoti P.; Sumpter, Bobby G.; Fuentes-Cabrera, Miguel; Kerfeld, Cheryl A.; Ducat, Daniel C.

    2017-01-01

    As synthetic biology advances the intricacy of engineered biological systems, the importance of spatial organization within the cellular environment must not be marginalized. Increasingly, biological engineers are investigating means to control spatial organization within the cell, mimicking strategies used by natural pathways to increase flux and reduce cross-talk. A modular platform for constructing a diverse set of defined, programmable architectures would greatly assist in improving yields from introduced metabolic pathways and increasing insulation of other heterologous systems. Here, we review recent research on the shell proteins of bacterial microcompartments and discuss their potential application as “building blocks” for a range of customized intracellular scaffolds. We summarize the state of knowledge on the self-assembly of BMC shell proteins and discuss future avenues of research that will be important to realize the potential of BMC shell proteins as predictively assembling and programmable biological materials for bioengineering. PMID:28824573

  20. Tissue engineering applications of therapeutic cloning.

    PubMed

    Atala, Anthony; Koh, Chester J

    2004-01-01

    Few treatment options are available for patients suffering from diseased and injured organs because of a severe shortage of donor organs available for transplantation. Therapeutic cloning, where the nucleus from a donor cell is transferred into an enucleated oocyte in order to extract pluripotent embryonic stem cells, offers a potentially limitless source of cells for replacement therapy. Scientists in the field of tissue engineering apply the principles of cell transplantation, material science, and engineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. The present chapter reviews recent advances that have occurred in therapeutic cloning and tissue engineering and describes applications of these new technologies that may offer novel therapies for patients with end-stage organ failure.

  1. Engineered/designer biochar for contaminant removal/immobilization from soil and water: Potential and implication of biochar modification.

    PubMed

    Rajapaksha, Anushka Upamali; Chen, Season S; Tsang, Daniel C W; Zhang, Ming; Vithanage, Meththika; Mandal, Sanchita; Gao, Bin; Bolan, Nanthi S; Ok, Yong Sik

    2016-04-01

    The use of biochar has been suggested as a means of remediating contaminated soil and water. The practical applications of conventional biochar for contaminant immobilization and removal however need further improvements. Hence, recent attention has focused on modification of biochar with novel structures and surface properties in order to improve its remediation efficacy and environmental benefits. Engineered/designer biochars are commonly used terms to indicate application-oriented, outcome-based biochar modification or synthesis. In recent years, biochar modifications involving various methods such as, acid treatment, base treatment, amination, surfactant modification, impregnation of mineral sorbents, steam activation and magnetic modification have been widely studied. This review summarizes and evaluates biochar modification methods, corresponding mechanisms, and their benefits for contaminant management in soil and water. Applicability and performance of modification methods depend on the type of contaminants (i.e., inorganic/organic, anionic/cationic, hydrophilic/hydrophobic, polar/non-polar), environmental conditions, remediation goals, and land use purpose. In general, modification to produce engineered/designer biochar is likely to enhance the sorption capacity of biochar and its potential applications for environmental remediation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Development of feature extraction analysis for a multi-functional optical profiling device applied to field engineering applications

    NASA Astrophysics Data System (ADS)

    Han, Xu; Xie, Guangping; Laflen, Brandon; Jia, Ming; Song, Guiju; Harding, Kevin G.

    2015-05-01

    In the real application environment of field engineering, a large variety of metrology tools are required by the technician to inspect part profile features. However, some of these tools are burdensome and only address a sole application or measurement. In other cases, standard tools lack the capability of accessing irregular profile features. Customers of field engineering want the next generation metrology devices to have the ability to replace the many current tools with one single device. This paper will describe a method based on the ring optical gage concept to the measurement of numerous kinds of profile features useful for the field technician. The ring optical system is composed of a collimated laser, a conical mirror and a CCD camera. To be useful for a wide range of applications, the ring optical system requires profile feature extraction algorithms and data manipulation directed toward real world applications in field operation. The paper will discuss such practical applications as measuring the non-ideal round hole with both off-centered and oblique axes. The algorithms needed to analyze other features such as measuring the width of gaps, radius of transition fillets, fall of step surfaces, and surface parallelism will also be discussed in this paper. With the assistance of image processing and geometric algorithms, these features can be extracted with a reasonable performance. Tailoring the feature extraction analysis to this specific gage offers the potential for a wider application base beyond simple inner diameter measurements. The paper will present experimental results that are compared with standard gages to prove the performance and feasibility of the analysis in real world field engineering. Potential accuracy improvement methods, a new dual ring design and future work will be discussed at the end of this paper.

  3. Concise review: tailoring bioengineered scaffolds for stem cell applications in tissue engineering and regenerative medicine.

    PubMed

    Cosson, Steffen; Otte, Ellen A; Hezaveh, Hadi; Cooper-White, Justin J

    2015-02-01

    The potential for the clinical application of stem cells in tissue regeneration is clearly significant. However, this potential has remained largely unrealized owing to the persistent challenges in reproducibly, with tight quality criteria, and expanding and controlling the fate of stem cells in vitro and in vivo. Tissue engineering approaches that rely on reformatting traditional Food and Drug Administration-approved biomedical polymers from fixation devices to porous scaffolds have been shown to lack the complexity required for in vitro stem cell culture models or translation to in vivo applications with high efficacy. This realization has spurred the development of advanced mimetic biomaterials and scaffolds to increasingly enhance our ability to control the cellular microenvironment and, consequently, stem cell fate. New insights into the biology of stem cells are expected to eventuate from these advances in material science, in particular, from synthetic hydrogels that display physicochemical properties reminiscent of the natural cell microenvironment and that can be engineered to display or encode essential biological cues. Merging these advanced biomaterials with high-throughput methods to systematically, and in an unbiased manner, probe the role of scaffold biophysical and biochemical elements on stem cell fate will permit the identification of novel key stem cell behavioral effectors, allow improved in vitro replication of requisite in vivo niche functions, and, ultimately, have a profound impact on our understanding of stem cell biology and unlock their clinical potential in tissue engineering and regenerative medicine. ©AlphaMed Press.

  4. [Research progress of in vivo bioreactor as vascularization strategies in bone tissue engineering].

    PubMed

    Zhang, Haifeng; Han, Dong

    2014-09-01

    To review the application and research progress of in vivo bioreactor as vascularization strategies in bone tissue engineering. The original articles about in vivo bioreactor that can enhance vascularization of tissue engineered bone were extensively reviewed and analyzed. The in vivo bioreactor can be created by periosteum, muscle, muscularis membrane, and fascia flap as well as biomaterials. Using in vivo bioreactor can effectively promote the establishment of a microcirculation in the tissue engineered bones, especially for large bone defects. However, main correlative researches, currently, are focused on animal experiments, more clinical trials will be carried out in the future. With the rapid development of related technologies of bone tissue engineering, the use of in vivo bioreactor will to a large extent solve the bottleneck limitations and has the potential values for clinical application.

  5. Genetic engineering of industrial strains of Saccharomyces cerevisiae.

    PubMed

    Le Borgne, Sylvie

    2012-01-01

    Genetic engineering has been successfully applied to Saccharomyces cerevisiae laboratory strains for different purposes: extension of substrate range, improvement of productivity and yield, elimination of by-products, improvement of process performance and cellular properties, and extension of product range. The potential of genetically engineered yeasts for the massive production of biofuels as bioethanol and other nonfuel products from renewable resources as lignocellulosic biomass hydrolysates has been recognized. For such applications, robust industrial strains of S. cerevisiae have to be used. Here, some relevant genetic and genomic characteristics of industrial strains are discussed in relation to the problematic of the genetic engineering of such strains. General molecular tools applicable to the manipulation of S. cerevisiae industrial strains are presented and examples of genetically engineered industrial strains developed for the production of bioethanol from lignocellulosic biomass are given.

  6. Lightweight aircraft engines, the potential and problems for use of automotive fuels

    NASA Technical Reports Server (NTRS)

    Patterson, D. J.

    1983-01-01

    A comprehensive data research and analysis for evaluating the use of automotive fuels as a substitute for aviation grade fuel by piston-type general aviation aircraft engines is presented. Historically known problems and potential problems with fuels were reviewed for possible impact relative to application to an aircraft operational environment. This report reviews areas such as: fuel specification requirements, combustion knock, preignition, vapor lock, spark plug fouling, additives for fuel and oil, and storage stability.

  7. Earthquake Response of Concrete Gravity Dams Including Hydrodynamic and Foundation Interaction Effects,

    DTIC Science & Technology

    1980-01-01

    standard procedure for Analysis of all types of civil engineering struc- tures. Early in its development, it became apparent that this method had...unique potentialities in the evaluation of stress in dams, and many of its earliest civil engineering applications concerned special problems associated...with such structures [3,4]. The earliest dynamic finite element analyses of civil engineering structures involved the earthquake response analysis of

  8. Different methods of dentin processing for application in bone tissue engineering: A systematic review.

    PubMed

    Tabatabaei, Fahimeh Sadat; Tatari, Saeed; Samadi, Ramin; Moharamzadeh, Keyvan

    2016-10-01

    Dentin has become an interesting potential biomaterial for tissue engineering of oral hard tissues. It can be used as a scaffold or as a source of growth factors in bone tissue engineering. Different forms of dentin have been studied for their potential use as bone substitutes. Here, we systematically review different methods of dentin preparation and the efficacy of processed dentin in bone tissue engineering. An electronic search was carried out in PubMed and Scopus databases for articles published from 2000 to 2016. Studies on dentin preparation for application in bone tissue engineering were selected. The initial search yielded a total of 1045 articles, of which 37 were finally selected. Review of studies showed that demineralization was the most commonly used dentin preparation process for use in tissue engineering. Dentin extract, dentin particles (tooth ash), freeze-dried dentin, and denatured dentin are others method of dentin preparation. Based on our literature review, we can conclude that preparation procedure and the size and shape of dentin particles play an important role in its osteoinductive and osteoconductive properties. Standardization of these methods is important to draw a conclusion in this regard. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2616-2627, 2016. © 2016 Wiley Periodicals, Inc.

  9. Energetic Combustion Devices for Aerospace Propulsion and Power

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.

    2000-01-01

    Chemical reactions have long been the mainstay thermal energy source for aerospace propulsion and power. Although it is widely recognized that the intrinsic energy density limitations of chemical bonds place severe constraints on maximum realizable performance, it will likely be several years before systems based on high energy density nuclear fuels can be placed into routine service. In the mean time, efforts to develop high energy density chemicals and advanced combustion devices which can utilize such energetic fuels may yield worthwhile returns in overall system performance and cost. Current efforts in this vein are being carried out at NASA MSFC under the direction of the author in the areas of pulse detonation engine technology development and light metals combustion devices. Pulse detonation engines are touted as a low cost alternative to gas turbine engines and to conventional rocket engines, but actual performance and cost benefits have yet to be convincingly demonstrated. Light metal fueled engines also offer potential benefits in certain niche applications such as aluminum/CO2 fueled engines for endo-atmospheric Martian propulsion. Light metal fueled MHD generators also present promising opportunities with respect to electric power generation for electromagnetic launch assist. This presentation will discuss the applications potential of these concepts with respect to aero ace propulsion and power and will review the current status of the development efforts.

  10. Geomagnetically induced currents: Science, engineering, and applications readiness

    NASA Astrophysics Data System (ADS)

    Pulkkinen, A.; Bernabeu, E.; Thomson, A.; Viljanen, A.; Pirjola, R.; Boteler, D.; Eichner, J.; Cilliers, P. J.; Welling, D.; Savani, N. P.; Weigel, R. S.; Love, J. J.; Balch, C.; Ngwira, C. M.; Crowley, G.; Schultz, A.; Kataoka, R.; Anderson, B.; Fugate, D.; Simpson, J. J.; MacAlester, M.

    2017-07-01

    This paper is the primary deliverable of the very first NASA Living With a Star Institute Working Group, Geomagnetically Induced Currents (GIC) Working Group. The paper provides a broad overview of the current status and future challenges pertaining to the science, engineering, and applications of the GIC problem. Science is understood here as the basic space and Earth sciences research that allows improved understanding and physics-based modeling of the physical processes behind GIC. Engineering, in turn, is understood here as the "impact" aspect of GIC. Applications are understood as the models, tools, and activities that can provide actionable information to entities such as power systems operators for mitigating the effects of GIC and government agencies for managing any potential consequences from GIC impact to critical infrastructure. Applications can be considered the ultimate goal of our GIC work. In assessing the status of the field, we quantify the readiness of various applications in the mitigation context. We use the Applications Readiness Level (ARL) concept to carry out the quantification.

  11. Geomagnetically induced currents: Science, engineering, and applications readiness

    USGS Publications Warehouse

    Pulkkinen, Antti; Bernabeu, E.; Thomson, A.; Viljanen, A.; Pirjola, R.; Boteler, D.; Eichner, J.; Cilliers, P.J.; Welling, D.; Savani, N.P.; Weigel, R.S.; Love, Jeffrey J.; Balch, Christopher; Ngwira, C.M.; Crowley, G.; Schultz, Adam; Kataoka, R.; Anderson, B.; Fugate, D.; Simpson, J.J.; MacAlester, M.

    2017-01-01

    This paper is the primary deliverable of the very first NASA Living With a Star Institute Working Group, Geomagnetically Induced Currents (GIC) Working Group. The paper provides a broad overview of the current status and future challenges pertaining to the science, engineering, and applications of the GIC problem. Science is understood here as the basic space and Earth sciences research that allows improved understanding and physics-based modeling of the physical processes behind GIC. Engineering, in turn, is understood here as the “impact” aspect of GIC. Applications are understood as the models, tools, and activities that can provide actionable information to entities such as power systems operators for mitigating the effects of GIC and government agencies for managing any potential consequences from GIC impact to critical infrastructure. Applications can be considered the ultimate goal of our GIC work. In assessing the status of the field, we quantify the readiness of various applications in the mitigation context. We use the Applications Readiness Level (ARL) concept to carry out the quantification.

  12. The concepts and applications of tissue engineering in otorhinolaryngology.

    PubMed

    Ribeiro, Leandro; Castro, Eugénia; Ferreira, Manuela; Helena, Diamantino; Robles, Raquel; Faria E Almeida, António; Condé, Artur

    2015-01-01

    Tissue engineering is a rapidly developing field that, making biological substitutes for the repair and regeneration of damaged tissues, will play an important role in the future of otorhinolaryngology. In this article we explain the principles of regenerative medicine and its potential applications in Otorhinolaryngology. The authors searched the published literature on this topic, chose relevant references, and extracted and systematized the data. There are some exciting possibilities for future treatments in otorhinolaryngology applying the concepts of tissue engineering. Copyright © 2014 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

  13. Evaluation of a staged fuel combustor for turboprop engines

    NASA Technical Reports Server (NTRS)

    Verdouw, A. J.

    1976-01-01

    Proposed EPA emission regulations require emission reduction by 1979 for various gas turbine engine classes. Extensive combustion technology advancements are required to meet the proposed regulations. The T56 turboprop engine requires CO, UHC, and smoke reduction. A staged fuel combustor design was tested on a combustion rig to evaluate emission reduction potential in turboprop engines from fuel zoning. The can-type combustor has separately fueled-pilot and main combustion zones in series. The main zone fueling system was arranged for potential incorporation into the T56 with minor or no modifications to the basic engine. Three combustor variable geometry systems were incorporated to evaluate various airflow distributions. Emission results with fixed geometry operation met all proposed EPA regulations over the EPA LTO cycle. CO reduction was 82 percent, UHC reduction was 96 percent, and smoke reduction was 84 percent. NOx increased 14 percent over the LTO cycle. At high power, NOx reduction was 40 to 55 percent. This NOx reduction has potential application to stationary gas turbine powerplants which have different EPA regulations.

  14. Engineering ellipsoidal cap-like hydrogel particles as building blocks or sacrificial templates for three-dimensional cell culture.

    PubMed

    Zhang, Weiwei; Huang, Guoyou; Ng, Kelvin; Ji, Yuan; Gao, Bin; Huang, Liqing; Zhou, Jinxiong; Lu, Tian Jian; Xu, Feng

    2018-03-26

    Hydrogel particles that can be engineered to compartmentally culture cells in a three-dimensional (3D) and high-throughput manner have attracted increasing interest in the biomedical area. However, the ability to generate hydrogel particles with specially designed structures and their potential biomedical applications need to be further explored. This work introduces a method for fabricating hydrogel particles in an ellipsoidal cap-like shape (i.e., ellipsoidal cap-like hydrogel particles) by employing an open-pore anodic aluminum oxide membrane. Hydrogel particles of different sizes are fabricated. The ability to produce ellipsoidal cap-like magnetic hydrogel particles with controlled distribution of magnetic nanoparticles is demonstrated. Encapsulated cells show high viability, indicating the potential for using these hydrogel particles as structure- and remote-controllable building blocks for tissue engineering application. Moreover, the hydrogel particles are also used as sacrificial templates for fabricating ellipsoidal cap-like concave wells, which are further applied for producing size controllable cell aggregates. The results are beneficial for the development of hydrogel particles and their applications in 3D cell culture.

  15. The Engineering Potential of Rhodosporidium toruloides as a Workhorse for Biotechnological Applications.

    PubMed

    Park, Young-Kyoung; Nicaud, Jean-Marc; Ledesma-Amaro, Rodrigo

    2018-03-01

    Moving our society towards a bioeconomy requires efficient and sustainable microbial production of chemicals and fuels. Rhodotorula (Rhodosporidium) toruloides is a yeast that naturally synthesizes substantial amounts of specialty chemicals and has been recently engineered to (i) enhance its natural production of lipids and carotenoids, and (ii) produce novel industrially relevant compounds. The use of R. toruloides by companies and research groups has exponentially increased in recent years as a result of recent improvements in genetic engineering techniques and the availability of multiomics information on its genome and metabolism. This review focuses on recent engineering approaches in R. toruloides for bioproduction and explores its potential as a biotechnological chassis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Airframe-integrated propulsion system for hypersonic cruise vehicles

    NASA Technical Reports Server (NTRS)

    Jones, R. A.; Huber, P. W.

    1978-01-01

    The paper describes a new hydrogen-burning airframe-integrated scramjet concept which offers good potential for efficient hypersonic cruise vehicles. The characteristics of the engine which assure good performance are extensive engine-airframe integration, fixed geometry, low cooling, and control of heat release in the supersonic combustor by mixed modes of fuel injection from the combustor entrance. The present paper describes the concept and presents results from inlet tests, direct-connect combustor tests, and tests of two subscale boiler-plate research engines currently underway under conditions which simulate flight at Mach 4 and 7. It is concluded that this engine concept has the potential for high thrust and efficiency, low drag and weight, low cooling requirement, and application to a wide range of vehicle sizes.

  17. Engineering Protein Hydrogels Using SpyCatcher-SpyTag Chemistry.

    PubMed

    Gao, Xiaoye; Fang, Jie; Xue, Bin; Fu, Linglan; Li, Hongbin

    2016-09-12

    Constructing hydrogels from engineered proteins has attracted significant attention within the material sciences, owing to their myriad potential applications in biomedical engineering. Developing efficient methods to cross-link tailored protein building blocks into hydrogels with desirable mechanical, physical, and functional properties is of paramount importance. By making use of the recently developed SpyCatcher-SpyTag chemistry, we successfully engineered protein hydrogels on the basis of engineered tandem modular elastomeric proteins. Our resultant protein hydrogels are soft but stable, and show excellent biocompatibility. As the first step, we tested the use of these hydrogels as a drug carrier, as well as in encapsulating human lung fibroblast cells. Our results demonstrate the robustness of the SpyCatcher-SpyTag chemistry, even when the SpyTag (or SpyCatcher) is flanked by folded globular domains. These results demonstrate that SpyCatcher-SpyTag chemistry can be used to engineer protein hydrogels from tandem modular elastomeric proteins that can find applications in tissue engineering, in fundamental mechano-biological studies, and as a controlled drug release vehicle.

  18. Dielectric properties of agricultural materials and their application

    USDA-ARS?s Scientific Manuscript database

    This book is prepared as a comprehensive source of information on dielectric properties of agricultural materials for scientific researchers and engineers involved in practical application of radio-frequency and microwave energy for potential problem solutions. Dielectric properties of materials det...

  19. An Investigation of Applications for Thermodynamic Work Potential Methods: Working Tables and Charts for Estimation of Thermodynamic Work Potential in Equilibrium Mixtures of Jet-A and Air

    NASA Technical Reports Server (NTRS)

    Mavris, Dimitri; Roth, Bryce; McDonald, Rob

    2002-01-01

    The objective of this report is to provide a tool to facilitate the application of thermodynamic work potential methods to aircraft and engine analysis. This starts with a discussion of the theoretical background underlying these methods, which is then used to derive various equations useful for thermodynamic analysis of aircraft engines. The work potential analysis method is implemented in the form of a set of working charts and tables that can be used to graphically evaluate work potential stored in high-enthalpy gas. The range of validity for these tables is 300 to 36,000 R, pressures between between 0.01 atm and 100 atm, and fuel-air ratios from zero to stoichiometric. The derivations and charts assume mixtures of Jet-A and air as the working fluid. The thermodynamic properties presented in these charts were calculated based upon standard thermodynamic curve fits.

  20. Parabolic dish systems at work - Applying the concepts

    NASA Technical Reports Server (NTRS)

    Marriott, A. T.

    1981-01-01

    An overview is given of parabolic dish solar concentrator application experiments being conducted by the U.S. Department of Energy. The 'engineering experiments' comprise the testing of (1) a small-community powerplant system, in conjunction with a grid-connected utility; (2) stand-alone applications at remote sites such as military installations, radar stations and villages; and (3) dish modules that can deliver heat for direct use in industrial processes. Applicability projections are based on a dish and receiver that use a Brayton engine with an engine/generator efficiency of 25% and a production level of up to 25,000 units per year. Analyses indicate that parabolic-dish power systems can potentially replace small, oil-fired power plants in all regions of the U.S. between 1985 and 1991.

  1. Silk Materials Functionalized via Genetic Engineering for Biomedical Applications.

    PubMed

    Deptuch, Tomasz; Dams-Kozlowska, Hanna

    2017-12-12

    The great mechanical properties, biocompatibility and biodegradability of silk-based materials make them applicable to the biomedical field. Genetic engineering enables the construction of synthetic equivalents of natural silks. Knowledge about the relationship between the structure and function of silk proteins enables the design of bioengineered silks that can serve as the foundation of new biomaterials. Furthermore, in order to better address the needs of modern biomedicine, genetic engineering can be used to obtain silk-based materials with new functionalities. Sequences encoding new peptides or domains can be added to the sequences encoding the silk proteins. The expression of one cDNA fragment indicates that each silk molecule is related to a functional fragment. This review summarizes the proposed genetic functionalization of silk-based materials that can be potentially useful for biomedical applications.

  2. Magnetic Resonance Imaging and Velocity Mapping in Chemical Engineering Applications.

    PubMed

    Gladden, Lynn F; Sederman, Andrew J

    2017-06-07

    This review aims to illustrate the diversity of measurements that can be made using magnetic resonance techniques, which have the potential to provide insights into chemical engineering systems that cannot readily be achieved using any other method. Perhaps the most notable advantage in using magnetic resonance methods is that both chemistry and transport can be followed in three dimensions, in optically opaque systems, and without the need for tracers to be introduced into the system. Here we focus on hydrodynamics and, in particular, applications to rheology, pipe flow, and fixed-bed and gas-solid fluidized bed reactors. With increasing development of industrially relevant sample environments and undersampling data acquisition strategies that can reduce acquisition times to <1 s, magnetic resonance is finding increasing application in chemical engineering research.

  3. Gravity, Tissue Engineering, and the Missing Link.

    PubMed

    Costa-Almeida, Raquel; Granja, Pedro L; Gomes, Manuela E

    2018-04-01

    The influence of microgravity and hypergravity on living systems has attracted significant attention, but the use of these tools in tissue engineering (TE) remains relatively unexplored. This Forum article highlights an emerging field of research to uncover new potential applications at the interface between altered gravity and TE. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Nanomaterials for Engineering Stem Cell Responses.

    PubMed

    Kerativitayanan, Punyavee; Carrow, James K; Gaharwar, Akhilesh K

    2015-08-05

    Recent progress in nanotechnology has stimulated the development of multifunctional biomaterials for tissue engineering applications. Synergistic interactions between nanomaterials and stem cell engineering offer numerous possibilities to address some of the daunting challenges in regenerative medicine, such as controlling trigger differentiation, immune reactions, limited supply of stem cells, and engineering complex tissue structures. Specifically, the interactions between stem cells and their microenvironment play key roles in controlling stem cell fate, which underlines therapeutic success. However, the interactions between nanomaterials and stem cells are not well understood, and the effects of the nanomaterials shape, surface morphology, and chemical functionality on cellular processes need critical evaluation. In this Review, focus is put on recent development in nanomaterial-stem cell interactions, with specific emphasis on their application in regenerative medicine. Further, the emerging technologies based on nanomaterials developed over the past decade for stem cell engineering are reviewed, as well as the potential applications of these nanomaterials in tissue regeneration, stem cell isolation, and drug/gene delivery. It is anticipated that the enhanced understanding of nanomaterial-stem cell interactions will facilitate improved biomaterial design for a range of biomedical and biotechnological applications. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. An Assessment of Gas Foil Bearing Scalability and the Potential Benefits to Civilian Turbofan Engines

    NASA Technical Reports Server (NTRS)

    Bruckner, Robert J.

    2010-01-01

    Over the past several years the term oil-free turbomachinery has been used to describe a rotor support system for high speed turbomachinery that does not require oil for lubrication, damping, or cooling. The foundation technology for oil-free turbomachinery is the compliant foil bearing. This technology can replace the conventional rolling element bearings found in current engines. Two major benefits are realized with this technology. The primary benefit is the elimination of the oil lubrication system, accessory gearbox, tower shaft, and one turbine frame. These components account for 8 to 13 percent of the turbofan engine weight. The second benefit that compliant foil bearings offer to turbofan engines is the capability to operate at higher rotational speeds and shaft diameters. While traditional rolling element bearings have diminished life, reliability, and load capacity with increasing speeds, the foil bearing has a load capacity proportional to speed. The traditional applications for foil bearings have been in small, lightweight machines. However, recent advancements in the design and manufacturing of foil bearings have increased their potential size. An analysis, grounded in experimentally proven operation, is performed to assess the scalability of the modern foil bearing. This analysis was coupled to the requirements of civilian turbofan engines. The application of the foil bearing to larger, high bypass ratio engines nominally at the 120 kN (approx.25000 lb) thrust class has been examined. The application of this advanced technology to this system was found to reduce mission fuel burn by 3.05 percent.

  6. A novel injectable temperature-sensitive zinc doped chitosan/β-glycerophosphate hydrogel for bone tissue engineering.

    PubMed

    Niranjan, Ramesh; Koushik, Chandru; Saravanan, Sekaran; Moorthi, Ambigapathi; Vairamani, Mariappanadar; Selvamurugan, Nagarajan

    2013-03-01

    Hydrogels are hydrophilic polymers that have a wide range of biomedical applications including bone tissue engineering. In this study we report preparation and characterization of a thermosensitive hydrogel (Zn-CS/β-GP) containing zinc (Zn), chitosan (CS) and beta-glycerophosphate (β-GP) for bone tissue engineering. The prepared hydrogel exhibited a liquid state at room temperature and turned into a gel at body temperature. The hydrogel was characterized by SEM, EDX, XRD, FT-IR and swelling studies. The hydrogel enhanced antibacterial activity and promoted osteoblast differentiation. Thus, we suggest that the Zn-CS/β-GP hydrogel could have potential impact as an injectable in situ forming scaffold for bone tissue engineering applications. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. A review of selected pumping systems in nature and engineering--potential biomimetic concepts for improving displacement pumps and pulsation damping.

    PubMed

    Bach, D; Schmich, F; Masselter, T; Speck, T

    2015-09-03

    The active transport of fluids by pumps plays an essential role in engineering and biology. Due to increasing energy costs and environmental issues, topics like noise reduction, increase of efficiency and enhanced robustness are of high importance in the development of pumps in engineering. The study compares pumps in biology and engineering and assesses biomimetic potentials for improving man-made pumping systems. To this aim, examples of common challenges, applications and current biomimetic research for state-of-the art pumps are presented. The biomimetic research is helped by the similar configuration of many positive displacement pumping systems in biology and engineering. In contrast, the configuration and underlying pumping principles for fluid dynamic pumps (FDPs) differ to a greater extent in biology and engineering. However, progress has been made for positive displacement as well as for FDPs by developing biomimetic devices with artificial muscles and cilia that improve energetic efficiency and fail-safe operation or reduce noise. The circulatory system of vertebrates holds a high biomimetic potential for the damping of pressure pulsations, a common challenge in engineering. Damping of blood pressure pulsation results from a nonlinear viscoelastic behavior of the artery walls which represent a complex composite material. The transfer of the underlying functional principle could lead to an improvement of existing technical solutions and be used to develop novel biomimetic damping solutions. To enhance efficiency or thrust of man-made fluid transportation systems, research on jet propulsion in biology has shown that a pulsed jet can be tuned to either maximize thrust or efficiency. The underlying principle has already been transferred into biomimetic applications in open channel water systems. Overall there is a high potential to learn from nature in order to improve pumping systems for challenges like the reduction of pressure pulsations, increase of jet propulsion efficiency or the reduction of wear.

  8. CRISPR technologies for bacterial systems: Current achievements and future directions.

    PubMed

    Choi, Kyeong Rok; Lee, Sang Yup

    2016-11-15

    Throughout the decades of its history, the advances in bacteria-based bio-industries have coincided with great leaps in strain engineering technologies. Recently unveiled clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated proteins (Cas) systems are now revolutionizing biotechnology as well as biology. Diverse technologies have been derived from CRISPR/Cas systems in bacteria, yet the applications unfortunately have not been actively employed in bacteria as extensively as in eukaryotic organisms. A recent trend of engineering less explored strains in industrial microbiology-metabolic engineering, synthetic biology, and other related disciplines-is demanding facile yet robust tools, and various CRISPR technologies have potential to cater to the demands. Here, we briefly review the science in CRISPR/Cas systems and the milestone inventions that enabled numerous CRISPR technologies. Next, we describe CRISPR/Cas-derived technologies for bacterial strain development, including genome editing and gene expression regulation applications. Then, other CRISPR technologies possessing great potential for industrial applications are described, including typing and tracking of bacterial strains, virome identification, vaccination of bacteria, and advanced antimicrobial approaches. For each application, we note our suggestions for additional improvements as well. In the same context, replication of CRISPR/Cas-based chromosome imaging technologies developed originally in eukaryotic systems is introduced with its potential impact on studying bacterial chromosomal dynamics. Also, the current patent status of CRISPR technologies is reviewed. Finally, we provide some insights to the future of CRISPR technologies for bacterial systems by proposing complementary techniques to be developed for the use of CRISPR technologies in even wider range of applications. Copyright © 2016. Published by Elsevier Inc.

  9. Design of lightning protection for a full-authority digital engine control

    NASA Technical Reports Server (NTRS)

    Dargi, M.; Rupke, E.; Wiles, K.

    1991-01-01

    The steps and procedures are described which are necessary to achieve a successful lightning-protection design for a state-of-the-art Full-Authority Digital Engine Control (FADEC) system. The engine and control systems used as examples are fictional, but the design and verification methods are real. Topics discussed include: applicable airworthiness regulation, selection of equipment transient design and control levels for the engine/airframe and intra-engine segments of the system, the use of cable shields, terminal-protection devices and filter circuits in hardware protection design, and software approaches to minimize upset potential. Shield terminations, grounding, and bonding are also discussed, as are the important elements of certification and test plans, and the role of tests and analyses. Also included are examples of multiple-stroke and multiple-burst testing. A review of design pitfalls and challenges, and status of applicable test standards such as RTCA DO-160, Section 22, are presented.

  10. Evaluation of undeveloped rocket engine cycle applications to advanced transportation

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Undeveloped pump-fed, liquid propellant rocket engine cycles were assessed and evaluated for application to Next Manned Transportation System (NMTS) vehicles, which would include the evolving Space Transportation System (STS Evolution), the Personnel Launch System (PLS), and the Advanced Manned Launch System (AMLS). Undeveloped engine cycles selected for further analysis had potential for increased reliability, more maintainability, reduced cost, and improved (or possibly level) performance when compared to the existing SSME and proposed STME engines. The split expander (SX) cycle, the full flow staged combustion (FFSC) cycle, and a hybrid version of the FFSC, which has a LOX expander drive for the LOX pump, were selected for definition and analysis. Technology requirements and issues were identified and analyses of vehicle systems weight deltas using the SX and FFSC cycles in AMLS vehicles were performed. A strawman schedule and cost estimate for FFSC subsystem technology developments and integrated engine system demonstration was also provided.

  11. Micro-/nano-engineered cellular responses for soft tissue engineering and biomedical applications.

    PubMed

    Tay, Chor Yong; Irvine, Scott Alexander; Boey, Freddy Y C; Tan, Lay Poh; Venkatraman, Subbu

    2011-05-23

    The development of biomedical devices and reconstruction of functional ex vivo tissues often requires the need to fabricate biomimetic surfaces with features of sub-micrometer precision. This can be achieved with the advancements in micro-/nano-engineering techniques, allowing researchers to manipulate a plethora of cellular behaviors at the cell-biomaterial interface. Systematic studies conducted on these 2D engineered surfaces have unraveled numerous novel findings that can potentially be integrated as part of the design consideration for future 2D and 3D biomaterials and will no doubt greatly benefit tissue engineering. In this review, recent developments detailing the use of micro-/nano-engineering techniques to direct cellular orientation and function pertinent to soft tissue engineering will be highlighted. Particularly, this article aims to provide valuable insights into distinctive cell interactions and reactions to controlled surfaces, which can be exploited to understand the mechanisms of cell growth on micro-/nano-engineered interfaces, and to harness this knowledge to optimize the performance of 3D artificial soft tissue grafts and biomedical applications. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Chemical characterisation of dredged sediments in relation to their potential use in civil engineering.

    PubMed

    Zuliani, Tea; Mladenovič, Ana; Ščančar, Janez; Milačič, Radmila

    2016-04-01

    During capital and/or maintenance dredging operations, large amounts of material are produced. Instead of their discharge, dredged sediments may be a valuable natural resource if not contaminated. One of the possible areas of application is civil engineering. In the present work, the environmental status of seaport dredged sediment was evaluated in order to investigate its potential applicability as a secondary raw material. Sediments were analysed for element concentrations in digested samples, aqueous extracts and fractions from sequential extraction; for fluoride, chloride and sulphate concentrations in aqueous extracts; and for tributyltin (TBT). Granulometric and mineralogical compositions were also analysed. The elemental impact was evaluated by calculation of the enrichment factors. The total element concentrations determined showed moderate contamination of the dredged sediments as was confirmed also by their moderate enrichment factors, presumably as a result of industrial and port activities. Elemental concentrations in the aqueous extract were very low and therefore do not represent any hazard for the environment. The water-soluble element concentrations were under the threshold levels set by the EU Directive on the landfill of waste, on the basis of which the applicability of dredged sediments in civil engineering is evaluated, while the content of chloride and sulphate were above the threshold levels. It was found out that due to the large amounts of sediment available, civil engineering applications such as the construction of embankments and backfilling is the most beneficial recycling solution at present.

  13. Dental pulp stem cells express tendon markers under mechanical loading and are a potential cell source for tissue engineering of tendon-like tissue.

    PubMed

    Chen, Yu-Ying; He, Sheng-Teng; Yan, Fu-Hua; Zhou, Peng-Fei; Luo, Kai; Zhang, Yan-Ding; Xiao, Yin; Lin, Min-Kui

    2016-12-16

    Postnatal mesenchymal stem cells have the capacity to differentiate into multiple cell lineages. This study explored the possibility of dental pulp stem cells (DPSCs) for potential application in tendon tissue engineering. The expression of tendon-related markers such as scleraxis, tenascin-C, tenomodulin, eye absent homologue 2, collagens I and VI was detected in dental pulp tissue. Interestingly, under mechanical stimulation, these tendon-related markers were significantly enhanced when DPSCs were seeded in aligned polyglycolic acid (PGA) fibre scaffolds. Furthermore, mature tendon-like tissue was formed after transplantation of DPSC-PGA constructs under mechanical loading conditions in a mouse model. This study demonstrates that DPSCs could be a potential stem cell source for tissue engineering of tendon-like tissue.

  14. Electrospun Scaffolds for Tissue Engineering of Vascular Grafts

    PubMed Central

    Hasan, Anwarul; Memic, Adnan; Annabi, Nasim; Hossain, Monowar; Paul, Arghya; Dokmeci, Mehmet R.; Dehghani, Fariba; Khademhosseini, Ali

    2013-01-01

    There is a growing demand for off-the-shelf tissue engineered vascular grafts (TEVGs) for replacement or bypass of damaged arteries in various cardiovascular diseases. Scaffolds from the decellularized tissue skeletons to biopolymers and biodegradable synthetic polymers have been used for fabricating TEVGs. However, several issues have not yet been resolved, which include the inability to mimic the mechanical properties of native tissues, and the ability for long term patency and growth required for in vivo function. Electrospinning is a popular technique for the production of scaffolds that has the potential to address these issues. However, its application to human TEVGs has not yet been achieved. This review provides an overview of tubular scaffolds that have been prepared by electrospinning with potential for TEVG applications. PMID:23973391

  15. Biologically active chitosan systems for tissue engineering and regenerative medicine.

    PubMed

    Jiang, Tao; Kumbar, Sangamesh G; Nair, Lakshmi S; Laurencin, Cato T

    2008-01-01

    Biodegradable polymeric scaffolds are widely used as a temporary extracellular matrix in tissue engineering and regenerative medicine. By physical adsorption of biomolecules on scaffold surface, physical entrapment of biomolecules in polymer microspheres or hydrogels, and chemical immobilization of oligopeptides or proteins on biomaterials, biologically active biomaterials and scaffolds can be derived. These bioactive systems show great potential in tissue engineering in rendering bioactivity and/or specificity to scaffolds. This review highlights some of the biologically active chitosan systems for tissue engineering application and the associated strategies to develop such bioactive chitosan systems.

  16. Green Approach to the Synthesis of Nanomaterials and Sustainable Applications of Nano-Catalysts

    EPA Science Inventory

    The generation of engineered nanomaterials represents a major breakthrough and the successful commercialization of this disruptive technology is important for varied applications to humans and global growth but serious attention is needed for the assessment of potential health an...

  17. Application of laminar flow control to high-bypass-ratio turbofan engine nacelles

    NASA Technical Reports Server (NTRS)

    Wie, Y. S.; Collier, F. S., Jr.; Wagner, R. D.

    1991-01-01

    Recently, the concept of the application of hybrid laminar flow to modern commercial transport aircraft was successfully flight tested on a Boeing 757 aircraft. In this limited demonstration, in which only part of the upper surface of the swept wing was designed for the attainment of laminar flow, significant local drag reduction was measured. This paper addresses the potential application of this technology to laminarize the external surface of large, modern turbofan engine nacelles which may comprise as much as 5-10 percent of the total wetted area of future commercial transports. A hybrid-laminar-flow-control (HLFC) pressure distribution is specified and the corresponding nacelle geometry is computed utilizing a predictor/corrector design method. Linear stability calculations are conducted to provide predictions of the extent of the laminar boundary layer. Performance studies are presented to determine potential benefits in terms of reduced fuel consumption.

  18. Effects of Exposures on Superalloys for Space Applications

    NASA Technical Reports Server (NTRS)

    Gabb, Tim; Garg, Anita; Gayda, John

    2007-01-01

    The industry is demanding longer term service at high temperatures for nickel-base superalloys in gas turbine engine as well as potential space applications. However, longer term service can severely tax alloy phase stability, to the potential detriment of mechanical properties. Cast Mar-M247LC and wrought Haynes 230 superalloys were exposed and creep tested for extended times at elevated temperature. Microstructure and phase evaluations were then undertaken for comparisons.

  19. Stem Cells Applications in Regenerative Medicine and Disease Therapeutics

    PubMed Central

    2016-01-01

    Regenerative medicine, the most recent and emerging branch of medical science, deals with functional restoration of tissues or organs for the patient suffering from severe injuries or chronic disease. The spectacular progress in the field of stem cell research has laid the foundation for cell based therapies of disease which cannot be cured by conventional medicines. The indefinite self-renewal and potential to differentiate into other types of cells represent stem cells as frontiers of regenerative medicine. The transdifferentiating potential of stem cells varies with source and according to that regenerative applications also change. Advancements in gene editing and tissue engineering technology have endorsed the ex vivo remodelling of stem cells grown into 3D organoids and tissue structures for personalized applications. This review outlines the most recent advancement in transplantation and tissue engineering technologies of ESCs, TSPSCs, MSCs, UCSCs, BMSCs, and iPSCs in regenerative medicine. Additionally, this review also discusses stem cells regenerative application in wildlife conservation. PMID:27516776

  20. Nano-regenerative medicine towards clinical outcome of stem cell and tissue engineering in humans

    PubMed Central

    Arora, Pooja; Sindhu, Annu; Dilbaghi, Neeraj; Chaudhury, Ashok; Rajakumar, Govindasamy; Rahuman, Abdul Abdul

    2012-01-01

    Nanotechnology is a fast growing area of research that aims to create nanomaterials or nanostructures development in stem cell and tissue-based therapies. Concepts and discoveries from the fields of bio nano research provide exciting opportunities of using stem cells for regeneration of tissues and organs. The application of nanotechnology to stem-cell biology would be able to address the challenges of disease therapeutics. This review covers the potential of nanotechnology approaches towards regenerative medicine. Furthermore, it focuses on current aspects of stem- and tissue-cell engineering. The magnetic nanoparticles-based applications in stem-cell research open new frontiers in cell and tissue engineering. PMID:22260258

  1. Photonics education development for electrical engineering students

    NASA Astrophysics Data System (ADS)

    Cao, Yang; Luo, Yuan; Liu, Yu; Hu, ZhangFang; Cai, Xuemei

    2017-08-01

    We describe the contents of an advanced undergraduate course on photonics at School of Electrical Engineering, Chongqing University of Posts and Telecommunications. The main goal of the course is to equip the student with the necessary theoretical and practical knowledge to participate in photonics-related industry and further graduate level study and research if they choose. The prerequisites include college-level physics and higher mathematics which a general engineering student has already had in his/her first and second year college study. Although applications of photonics are ubiquitous such as telecommunications, photonic computing, spectroscopy, military technology, and biophotonics etc. Telecommunication information system application is more emphasized in our course considering about the potential job chances for our students.

  2. Airborne Nanostructured Particles and Occupational Health

    NASA Astrophysics Data System (ADS)

    Maynard, Andrew D.; Kuempel, Eileen D.

    2005-12-01

    Nanotechnology is leading to the development in many field, of new materials and devices in many fields that demonstrate nanostructure-dependent properties. However, concern has been expressed that these same properties may present unique challenges to addressing potential health impact. Airborne particles associated with engineered nanomaterials are of particular concern, as they can readily enter the body through inhalation. Research into the potential occupational health risks associated with inhaling engineered nanostructured particles is just beginning. However, there is a large body of data on occupational and environmental aerosols, which is applicable to developing an initial assessment of potential risk and risk reduction strategies. Epidemiological and pathological studies of occupational and environmental exposures to airborne particles and fibers provide information on the aerosol-related lung diseases and conditions that have been observed in humans. Toxicological studies provide information on the specific disease mechanisms, dose-response relationships, and the particle characteristics that influence toxicity, including the size, surface area, chemistry or reactivity, solubility, and shape. Potential health risk will depend on the magnitude and nature of exposures to airborne nanostructured particles, and on the release, dispersion, transformation and control of materials in the workplace. Aerosol control methods have not been well-characterized for nanometer diameter particles, although theory and limited experimental data indicate that conventional ventilation, engineering control and filtration approaches should be applicable in many situations. Current information supports the development of preliminary guiding principles on working with engineered nanomaterials. However critical research questions remain to be answered before the potential health risk of airborne nanostructured particles in the workplace can be fully addressed.

  3. Piezoelectric polymers as biomaterials for tissue engineering applications.

    PubMed

    Ribeiro, Clarisse; Sencadas, Vítor; Correia, Daniela M; Lanceros-Méndez, Senentxu

    2015-12-01

    Tissue engineering often rely on scaffolds for supporting cell differentiation and growth. Novel paradigms for tissue engineering include the need of active or smart scaffolds in order to properly regenerate specific tissues. In particular, as electrical and electromechanical clues are among the most relevant ones in determining tissue functionality in tissues such as muscle and bone, among others, electroactive materials and, in particular, piezoelectric ones, show strong potential for novel tissue engineering strategies, in particular taking also into account the existence of these phenomena within some specific tissues, indicating their requirement also during tissue regeneration. This referee reports on piezoelectric materials used for tissue engineering applications. The most used materials for tissue engineering strategies are reported together with the main achievements, challenges and future needs for research and actual therapies. This review provides thus a compilation of the most relevant results and strategies and a start point for novel research pathways in the most relevant and challenging open questions. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Considerations for Using an Incremental Scheduler for Human Exploration Task Scheduling

    NASA Technical Reports Server (NTRS)

    Jaap, John; Phillips, Shaun

    2005-01-01

    As humankind embarks on longer space missions farther from home, the requirements and environments for scheduling the activities performed on these missions are changing. As we begin to prepare for these missions it is appropriate to evaluate the merits and applicability of the different types of scheduling engines. Scheduling engines temporally arrange tasks onto a timeline so that all constraints and objectives are met and resources are not overbooked. Scheduling engines used to schedule space missions fall into three general categories: batch, mixed-initiative, and incremental. This paper presents an assessment of the engine types, a discussion of the impact of human exploration of the moon and Mars on planning and scheduling, and the applicability of the different types of scheduling engines. This paper will pursue the hypothesis that incremental scheduling engines may have a place in the new environment; they have the potential to reduce cost, to improve the satisfaction of those who execute or benefit from a particular timeline (the customers), and to allow astronauts to plan their own tasks.

  5. Precision genome engineering in lactic acid bacteria

    PubMed Central

    2014-01-01

    Innovative new genome engineering technologies for manipulating chromosomes have appeared in the last decade. One of these technologies, recombination mediated genetic engineering (recombineering) allows for precision DNA engineering of chromosomes and plasmids in Escherichia coli. Single-stranded DNA recombineering (SSDR) allows for the generation of subtle mutations without the need for selection and without leaving behind any foreign DNA. In this review we discuss the application of SSDR technology in lactic acid bacteria, with an emphasis on key factors that were critical to move this technology from E. coli into Lactobacillus reuteri and Lactococcus lactis. We also provide a blueprint for how to proceed if one is attempting to establish SSDR technology in a lactic acid bacterium. The emergence of CRISPR-Cas technology in genome engineering and its potential application to enhancing SSDR in lactic acid bacteria is discussed. The ability to perform precision genome engineering in medically and industrially important lactic acid bacteria will allow for the genetic improvement of strains without compromising safety. PMID:25185700

  6. 78 FR 43216 - Government-Owned Inventions; Availability for Licensing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-19

    ... tissue for grafting. Potential Commercial Applications: Tissue engineering. Simulation of physiological... oxygen diffusivity silicone hydrogel support structures that mimic tissue vasculature (e.g., capillary...

  7. Investigation of specification measures for the Software Engineering Laboratory (SEL)

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Requirements specification measures are investigated for potential application in the Software Engineering Laboratory. Eighty-seven candidate measures are defined; sixteen are recommended for use. Most measures are derived from a new representation, the Composite Specification Model, which is introduced. The results of extracting the specification measures from the requirements of a real system are described.

  8. Space Telecommunications Radio System (STRS) Application Repository Design and Analysis

    NASA Technical Reports Server (NTRS)

    Handler, Louis M.

    2013-01-01

    The Space Telecommunications Radio System (STRS) Application Repository Design and Analysis document describes the STRS application repository for software-defined radio (SDR) applications intended to be compliant to the STRS Architecture Standard. The document provides information about the submission of artifacts to the STRS application repository, to provide information to the potential users of that information, and for the systems engineer to understand the requirements, concepts, and approach to the STRS application repository. The STRS application repository is intended to capture knowledge, documents, and other artifacts for each waveform application or other application outside of its project so that when the project ends, the knowledge is retained. The document describes the transmission of technology from mission to mission capturing lessons learned that are used for continuous improvement across projects and supporting NASA Procedural Requirements (NPRs) for performing software engineering projects and NASAs release process.

  9. Applications of Ecological Engineering Remedies for Uranium Processing Sites, USA

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Waugh, William

    The U.S. Department of Energy (USDOE) is responsible for remediation of environmental contamination and long-term stewardship of sites associated with the legacy of nuclear weapons production during the Cold War in the United States. Protection of human health and the environment will be required for hundreds or even thousands of years at many legacy sites. USDOE continually evaluates and applies advances in science and technology to improve the effectiveness and sustainability of surface and groundwater remedies (USDOE 2011). This paper is a synopsis of ecological engineering applications that USDOE is evaluating to assess the effectiveness of remedies at former uraniummore » processing sites in the southwestern United States. Ecological engineering remedies are predicated on the concept that natural ecological processes at legacy sites, once understood, can be beneficially enhanced or manipulated. Advances in tools for characterizing key processes and for monitoring remedy performance are demonstrating potential. We present test cases for four ecological engineering remedies that may be candidates for international applications.« less

  10. Silk Materials Functionalized via Genetic Engineering for Biomedical Applications

    PubMed Central

    Deptuch, Tomasz

    2017-01-01

    The great mechanical properties, biocompatibility and biodegradability of silk-based materials make them applicable to the biomedical field. Genetic engineering enables the construction of synthetic equivalents of natural silks. Knowledge about the relationship between the structure and function of silk proteins enables the design of bioengineered silks that can serve as the foundation of new biomaterials. Furthermore, in order to better address the needs of modern biomedicine, genetic engineering can be used to obtain silk-based materials with new functionalities. Sequences encoding new peptides or domains can be added to the sequences encoding the silk proteins. The expression of one cDNA fragment indicates that each silk molecule is related to a functional fragment. This review summarizes the proposed genetic functionalization of silk-based materials that can be potentially useful for biomedical applications. PMID:29231863

  11. Developing Systems Engineering Skills Through NASA Summer Intern Project

    NASA Technical Reports Server (NTRS)

    Bhasin, Kul; Barritt, Brian; Golden, Bert; Knoblock, Eric; Matthews, Seth; Warner, Joe

    2010-01-01

    During the Formulation phases of the NASA Project Life Cycle, communication systems engineers are responsible for designing space communication links and analyzing their performance to ensure that the proposed communication architecture is capable of satisfying high-level mission requirements. Senior engineers with extensive experience in communications systems perform these activities. However, the increasing complexity of space systems coupled with the current shortage of communications systems engineers has led to an urgent need for expedited training of new systems engineers. A pilot program, in which college-bound high school and undergraduate students studying various engineering disciplines are immersed in NASA s systems engineering practices, was conceived out of this need. This rapid summerlong training approach is feasible because of the availability of advanced software and technology tools and the students inherent ability to operate such tools. During this pilot internship program, a team of college-level and recently-hired engineers configured and utilized various software applications in the design and analysis of communication links for a plausible lunar sortie mission. The approach taken was to first design the direct-to-Earth communication links for the lunar mission elements, then to design the links between lunar surface and lunar orbital elements. Based on the data obtained from these software applications, an integrated communication system design was realized and the students gained valuable systems engineering knowledge. This paper describes this approach to rapidly training college-bound high school and undergraduate engineering students from various disciplines in NASA s systems engineering practices and tools. A summary of the potential use of NASA s emerging systems engineering internship program in broader applications is also described.

  12. Recent Progress on Systems and Synthetic Biology Approaches to Engineer Fungi As Microbial Cell Factories.

    PubMed

    Amores, Gerardo Ruiz; Guazzaroni, María-Eugenia; Arruda, Letícia Magalhães; Silva-Rocha, Rafael

    2016-04-01

    Filamentous fungi are remarkable organisms naturally specialized in deconstructing plant biomass and this feature has a tremendous potential for biofuel production from renewable sources. The past decades have been marked by a remarkable progress in the genetic engineering of fungi to generate industry-compatible strains needed for some biotech applications. In this sense, progress in this field has been marked by the utilization of high-throughput techniques to gain deep understanding of the molecular machinery controlling the physiology of these organisms, starting thus the Systems Biology era of fungi. Additionally, genetic engineering has been extensively applied to modify wellcharacterized promoters in order to construct new expression systems with enhanced performance under the conditions of interest. In this review, we discuss some aspects related to significant progress in the understating and engineering of fungi for biotechnological applications, with special focus on the construction of synthetic promoters and circuits in organisms relevant for industry. Different engineering approaches are shown, and their potential and limitations for the construction of complex synthetic circuits in these organisms are examined. Finally, we discuss the impact of engineered promoter architecture in the single-cell behavior of the system, an often-neglected relationship with a tremendous impact in the final performance of the process of interest. We expect to provide here some new directions to drive future research directed to the construction of high-performance, engineered fungal strains working as microbial cell factories.

  13. Three-dimensional bioprinting in tissue engineering and regenerative medicine.

    PubMed

    Gao, Guifang; Cui, Xiaofeng

    2016-02-01

    With the advances of stem cell research, development of intelligent biomaterials and three-dimensional biofabrication strategies, highly mimicked tissue or organs can be engineered. Among all the biofabrication approaches, bioprinting based on inkjet printing technology has the promises to deliver and create biomimicked tissue with high throughput, digital control, and the capacity of single cell manipulation. Therefore, this enabling technology has great potential in regenerative medicine and translational applications. The most current advances in organ and tissue bioprinting based on the thermal inkjet printing technology are described in this review, including vasculature, muscle, cartilage, and bone. In addition, the benign side effect of bioprinting to the printed mammalian cells can be utilized for gene or drug delivery, which can be achieved conveniently during precise cell placement for tissue construction. With layer-by-layer assembly, three-dimensional tissues with complex structures can be printed using converted medical images. Therefore, bioprinting based on thermal inkjet is so far the most optimal solution to engineer vascular system to the thick and complex tissues. Collectively, bioprinting has great potential and broad applications in tissue engineering and regenerative medicine. The future advances of bioprinting include the integration of different printing mechanisms to engineer biphasic or triphasic tissues with optimized scaffolds and further understanding of stem cell biology.

  14. Bioactive nanofibers for fibroblastic differentiation of mesenchymal precursor cells for ligament/tendon tissue engineering applications.

    PubMed

    Sahoo, Sambit; Ang, Lay-Teng; Cho-Hong Goh, James; Toh, Siew-Lok

    2010-02-01

    Mesenchymal stem cells and precursor cells are ideal candidates for tendon and ligament tissue engineering; however, for the stem cell-based approach to succeed, these cells would be required to proliferate and differentiate into tendon/ligament fibroblasts on the tissue engineering scaffold. Among the various fiber-based scaffolds that have been used in tendon/ligament tissue engineering, hybrid fibrous scaffolds comprising both microfibers and nanofibers have been recently shown to be particularly promising. With the nanofibrous coating presenting a biomimetic surface, the scaffolds can also potentially mimic the natural extracellular matrix in function by acting as a depot for sustained release of growth factors. In this study, we demonstrate that basic fibroblast growth factor (bFGF) could be successfully incorporated, randomly dispersed within blend-electrospun nanofibers and released in a bioactive form over 1 week. The released bioactive bFGF activated tyrosine phosphorylation signaling within seeded BMSCs. The bFGF-releasing nanofibrous scaffolds facilitated BMSC proliferation, upregulated gene expression of tendon/ligament-specific ECM proteins, increased production and deposition of collagen and tenascin-C, reduced multipotency of the BMSCs and induced tendon/ligament-like fibroblastic differentiation, indicating their potential in tendon/ligament tissue engineering applications. 2009 International Society of Differentiation. Published by Elsevier B.V. All rights reserved.

  15. Silk fibroin-based scaffolds for tissue engineering

    NASA Astrophysics Data System (ADS)

    Li, Zi-Heng; Ji, Shi-Chen; Wang, Ya-Zhen; Shen, Xing-Can; Liang, Hong

    2013-09-01

    Silk fibroin (SF) from the Bombyx mori silkworm exhibits attractive potential applications as biomechanical materials, due to its unique mechanical and biological properties. This review outlines the structure and properties of SF, including of its biocompatibility and biodegradability. It highlights recent researches on the fabrication of various SF-based composites scaffolds that are promising for tissue engineering applications, and discusses synthetic methods of various SF-based composites scaffolds and valuable approaches for controlling cell behaviors to promote the tissue repair. The function of extracellular matrices and their interaction with cells are also reviewed here.

  16. Engineered proteins as specific binding reagents.

    PubMed

    Binz, H Kaspar; Plückthun, Andreas

    2005-08-01

    Over the past 30 years, monoclonal antibodies have become the standard binding proteins and currently find applications in research, diagnostics and therapy. Yet, monoclonal antibodies now face strong competition from synthetic antibody libraries in combination with powerful library selection technologies. More recently, an increased understanding of other natural binding proteins together with advances in protein engineering, selection and evolution technologies has also triggered the exploration of numerous other protein architectures for the generation of designed binding molecules. Valuable protein-binding scaffolds have been obtained and represent promising alternatives to antibodies for biotechnological and, potentially, clinical applications.

  17. A controlled double-duration inducible gene expression system for cartilage tissue engineering.

    PubMed

    Ma, Ying; Li, Junxiang; Yao, Yi; Wei, Daixu; Wang, Rui; Wu, Qiong

    2016-05-25

    Cartilage engineering that combines competent seeding cells and a compatible scaffold is increasingly gaining popularity and is potentially useful for the treatment of various bone and cartilage diseases. Intensive efforts have been made by researchers to improve the viability and functionality of seeding cells of engineered constructs that are implanted into damaged cartilage. Here, we designed an integrative system combining gene engineering and the controlled-release concept to solve the problems of both seeding cell viability and functionality through precisely regulating the anti-apoptotic gene bcl-2 in the short-term and the chondrogenic master regulator Sox9 in the long-term. Both in vitro and in vivo experiments demonstrated that our system enhances the cell viability and chondrogenic effects of the engineered scaffold after introduction of the system while restricting anti-apoptotic gene expression to only the early stage, thereby preventing potential oncogenic and overdose effects. Our system was designed to be modular and can also be readily adapted to other tissue engineering applications with minor modification.

  18. Bio-inspired 3D microenvironments: a new dimension in tissue engineering.

    PubMed

    Magin, Chelsea M; Alge, Daniel L; Anseth, Kristi S

    2016-03-04

    Biomaterial scaffolds have been a foundational element of the tissue engineering paradigm since the inception of the field. Over the years there has been a progressive move toward the rational design and fabrication of bio-inspired materials that mimic the composition as well as the architecture and 3D structure of tissues. In this review, we chronicle advances in the field that address key challenges in tissue engineering as well as some emerging applications. Specifically, a summary of the materials and chemistries used to engineer bio-inspired 3D matrices that mimic numerous aspects of the extracellular matrix is provided, along with an overview of bioprinting, an additive manufacturing approach, for the fabrication of engineered tissues with precisely controlled 3D structures and architectures. To emphasize the potential clinical impact of the bio-inspired paradigm in biomaterials engineering, some applications of bio-inspired matrices are discussed in the context of translational tissue engineering. However, focus is also given to recent advances in the use of engineered 3D cellular microenvironments for fundamental studies in cell biology, including photoresponsive systems that are shedding new light on how matrix properties influence cell phenotype and function. In an outlook for future work, the need for high-throughput methods both for screening and fabrication is highlighted. Finally, microscale organ-on-a-chip technologies are highlighted as a promising area for future investment in the application of bio-inspired microenvironments.

  19. Liquid-fueled SOFC power sources for transportation

    NASA Astrophysics Data System (ADS)

    Myles, K. M.; Doshi, R.; Kumar, R.; Krumpelt, M.

    Traditionally, fuel cells have been developed for space or stationary terrestrial applications. As the first commercial 200-kW systems were being introduced by ONSI and Fuji Electric, the potentially much larger, but also more challenging, application in transportation was beginning to be addressed. As a result, fuel cell-powered buses have been designed and built, and R&D programs for fuel cell-powered passenger cars have been initiated. The engineering challenge of eventually replacing the internal combustion engine in buses, trucks, and passenger cars with fuel cell systems is to achieve much higher power densities and much lower costs than obtainable in systems designed for stationary applications. At present, the leading fuel cell candidate for transportation applications is, without question, the polymer electrolyte fuel cell (PEFC). Offering ambient temperature start-up and the potential for a relatively high power density, the polymer technology has attracted the interest of automotive manufacturers worldwide. But the difficulties of fuel handling for the PEFC have led to a growing interest in exploring the prospects for solid oxide fuel cells (SOFCs) operating on liquid fuels for transportation applications. Solid oxide fuel cells are much more compatible with liquid fuels (methanol or other hydrocarbons) and are potentially capable of power densities high enough for vehicular use. Two SOFC options for such use are discussed in this report.

  20. Robot-aided electrospinning toward intelligent biomedical engineering.

    PubMed

    Tan, Rong; Yang, Xiong; Shen, Yajing

    2017-01-01

    The rapid development of robotics offers new opportunities for the traditional biofabrication in higher accuracy and controllability, which provides great potentials for the intelligent biomedical engineering. This paper reviews the state of the art of robotics in a widely used biomaterial fabrication process, i.e., electrospinning, including its working principle, main applications, challenges, and prospects. First, the principle and technique of electrospinning are introduced by categorizing it to melt electrospinning, solution electrospinning, and near-field electrospinning. Then, the applications of electrospinning in biomedical engineering are introduced briefly from the aspects of drug delivery, tissue engineering, and wound dressing. After that, we conclude the existing problems in traditional electrospinning such as low production, rough nanofibers, and uncontrolled morphology, and then discuss how those problems are addressed by robotics via four case studies. Lastly, the challenges and outlooks of robotics in electrospinning are discussed and prospected.

  1. 3D bioprinting of scaffolds with living Schwann cells for potential nerve tissue engineering applications.

    PubMed

    Ning, Liqun; Sun, Haoying; Lelong, Tiphanie; Guilloteau, Romain; Zhu, Ning; Schreyer, David J; Chen, Daniel Xiongbiao

    2018-06-18

    Three-dimensional (3D) bioprinting of biomaterials shows great potential for producing cell-encapsulated scaffolds to repair nerves after injury or disease. For this, preparation of biomaterials and bioprinting itself are critical to create scaffolds with both biological and mechanical properties appropriate for nerve regeneration, yet remain unachievable. This paper presents our study on bioprinting Schwann cell-encapsulated scaffolds using composite hydrogels of alginate, fibrin, hyaluronic acid, and/or RGD peptide, for nerve tissue engineering applications. For the preparation of composite hydrogels, suitable hydrogel combinations were identified and prepared by adjusting the concentration of fibrin based on the morphological spreading of Schwann cells. In bioprinting, the effects of various printing process parameters (including the air pressure for dispensing, dispensing head movement speed, and crosslinking conditions) on printed structures were investigated and, by regulating these parameters, mechanically-stable scaffolds with fully interconnected pores were printed. The performance of Schwann cells within the printed scaffolds were examined in terms of viability, proliferation, orientation, and ability to produce laminin. Our results show that the printed scaffolds can promote the alignment of Schwann cells inside scaffolds and thus provide haptotactic cues to direct the extension of dorsal root ganglion neurites along the printed strands, demonstrating their great potential for applications in the field of nerve tissue engineering. © 2018 IOP Publishing Ltd.

  2. Applications of Ni3Al Based Intermetallic Alloys—Current Stage and Potential Perceptivities

    PubMed Central

    Jozwik, Pawel; Polkowski, Wojciech; Bojar, Zbigniew

    2015-01-01

    The paper presents an overview of current and prospective applications of Ni3Al based intermetallic alloys—modern engineering materials with special properties that are potentially useful for both structural and functional purposes. The bulk components manufactured from these materials are intended mainly for forging dies, furnace assembly, turbocharger components, valves, and piston head of internal combustion engines. The Ni3Al based alloys produced by a directional solidification are also considered as a material for the fabrication of jet engine turbine blades. Moreover, development of composite materials with Ni3Al based alloys as a matrix hardened by, e.g., TiC, ZrO2, WC, SiC and graphene, is also reported. Due to special physical and chemical properties; it is expected that these materials in the form of thin foils and strips should make a significant contribution to the production of high tech devices, e.g., Micro Electro-Mechanical Systems (MEMS) or Microtechnology-based Energy and Chemical Systems (MECS); as well as heat exchangers; microreactors; micro-actuators; components of combustion chambers and gasket of rocket and jet engines as well components of high specific strength systems. Additionally, their catalytic properties may find an application in catalytic converters, air purification systems from chemical and biological toxic agents or in a hydrogen “production” by a decomposition of hydrocarbons.

  3. The use of total human bone marrow fraction in a direct three-dimensional expansion approach for bone tissue engineering applications: focus on angiogenesis and osteogenesis.

    PubMed

    Guerrero, Julien; Oliveira, Hugo; Catros, Sylvain; Siadous, Robin; Derkaoui, Sidi-Mohammed; Bareille, Reine; Letourneur, Didier; Amédée, Joëlle

    2015-03-01

    Current approaches in bone tissue engineering have shown limited success, mostly owing to insufficient vascularization of the construct. A common approach consists of co-culture of endothelial cells and osteoblastic cells. This strategy uses cells from different sources and differentiation states, thus increasing the complexity upstream of a clinical application. The source of reparative cells is paramount for the success of bone tissue engineering applications. In this context, stem cells obtained from human bone marrow hold much promise. Here, we analyzed the potential of human whole bone marrow cells directly expanded in a three-dimensional (3D) polymer matrix and focused on the further characterization of this heterogeneous population and on their ability to promote angiogenesis and osteogenesis, both in vitro and in vivo, in a subcutaneous model. Cellular aggregates were formed within 24 h and over the 12-day culture period expressed endothelial and bone-specific markers and a specific junctional protein. Ectopic implantation of the tissue-engineered constructs revealed osteoid tissue and vessel formation both at the periphery and within the implant. This work sheds light on the potential clinical use of human whole bone marrow for bone regeneration strategies, focusing on a simplified approach to develop a direct 3D culture without two-dimensional isolation or expansion.

  4. Stochastic stability assessment of a semi-free piston engine generator concept

    NASA Astrophysics Data System (ADS)

    Kigezi, T. N.; Gonzalez Anaya, J. A.; Dunne, J. F.

    2016-09-01

    Small engines, as power generators with low-noise and vibration characteristics, are needed in two niche application areas: as electric vehicle range extenders and as domestic micro Combined Heat and Power systems. A recent semi-free piston design known as the AMOCATIC generator fully meets this requirement. The engine potentially allows for high energy conversion efficiencies at resonance derived from having a mass and spring assembly. As with free-piston engines in general, stability and control of piston motion has been cited as the prime challenge limiting the technology's widespread application. Using physical principles, we derive in this paper two important results: an energy balance criterion and a related general stability criterion for a semi-free piston engine. Control is achieved by systematically designing a Proportional Integral (PI) controller using a control-oriented engine model for which a specific stability condition is stated. All results are presented in closed form throughout the paper. Simulation results under stochastic pressure conditions show that the proposed energy balance, stability criterion, and PI controller, operate as predicted to yield stable engine operation at fixed compression ratio.

  5. Incremental Scheduling Engines for Human Exploration of the Cosmos

    NASA Technical Reports Server (NTRS)

    Jaap, John; Phillips, Shaun

    2005-01-01

    As humankind embarks on longer space missions farther from home, the requirements and environments for scheduling the activities performed on these missions are changing. As we begin to prepare for these missions it is appropriate to evaluate the merits and applicability of the different types of scheduling engines. Scheduling engines temporally arrange tasks onto a timeline so that all constraints and objectives are met and resources are not overbooked. Scheduling engines used to schedule space missions fall into three general categories: batch, mixed-initiative, and incremental. This paper presents an assessment of the engine types, a discussion of the impact of human exploration of the moon and Mars on planning and scheduling, and the applicability of the different types of scheduling engines. This paper will pursue the hypothesis that incremental scheduling engines may have a place in the new environment; they have the potential to reduce cost, to improve the satisfaction of those who execute or benefit from a particular timeline (the customers), and to allow astronauts to plan their own tasks and those of their companion robots.

  6. Incremental Scheduling Engines: Cost Savings through Automation

    NASA Technical Reports Server (NTRS)

    Jaap, John; Phillips, Shaun

    2005-01-01

    As humankind embarks on longer space missions farther from home, the requirements and environments for scheduling the activities performed on these missions are changing. As we begin to prepare for these missions it is appropriate to evaluate the merits and applicability of the different types of scheduling engines. Scheduling engines temporally arrange tasks onto a timeline so that all constraints and ob.jectives are met and resources are not over-booked. Scheduling engines used to schedule space missions fall into three general categories: batch, mixed-initiative, and incremental. This paper, presents an assessment of the engine types, a discussion of the impact of human exploration of the moon and Mars on planning and scheduling, and the applicability of the different types of scheduling engines. This paper will pursue the hypothesis that incremental scheduling engines may have a place in the new environment; they have the potential to reduce cost, to improve the satisfaction of those who execute or benefit from a particular timeline (the customers), and to allow astronauts to plan their own tasks and those of their companion robots.

  7. Survival differences among freeze-dried genetically engineered and wild-type bacteria.

    PubMed Central

    Israeli, E; Shaffer, B T; Hoyt, J A; Lighthart, B; Ganio, L M

    1993-01-01

    Because the death mechanisms of freeze-dried and air-dried bacteria are thought to be similar, freeze-drying was used to investigate the survival differences between potentially airborne genetically engineered microorganisms and their wild types. To this end, engineered strains of Escherichia coli and Pseudomonas syringae were freeze-dried and exposed to air, visible light, or both. The death rates of all engineered strains were significantly higher than those of their parental strains. Light and air exposure were found to increase the death rates of all strains. Application of death rate models to freeze-dried engineered bacteria to be released into the environment is discussed. PMID:8434925

  8. Engineering Research and Technology Development on the Space Station

    NASA Technical Reports Server (NTRS)

    1996-01-01

    This report identifies and assesses the kinds of engineering research and technology development applicable to national, NASA, and commercial needs that can appropriately be performed on the space station. It also identifies the types of instrumentation that should be included in the space station design to support engineering research. The report contains a preliminary assessment of the potential benefits to U.S. competitiveness of engineering research that might be conducted on a space station, reviews NASA's current approach to jointly funded or cooperative experiments, and suggests modifications that might facilitate university and industry participation in engineering research and technology development activities on the space station.

  9. Optics in engineering education: stimulating the interest of first-year students

    NASA Astrophysics Data System (ADS)

    Blanco-García, Jesús; Vazquez-Dorrío, Benito

    2014-07-01

    The work here presented deals with stimulating the interest for optics in first-year students of an Engineering School, which are not specifically following Optical Engineering studies. Optic-based technologies are nowadays wide spread, and growing, in almost all the engineering fields (from non destructive testing or alignments to power laser applications, fiber optic communications, memory devices, etc.). In general, the first year curriculum doesn't allow a detailed review of the main light properties, least its technical applications. We present in this paper our experience in showing some basic optic concepts and related technologies to the students of our school. Based on the fact that they have a very basic training in this branch of physics, we have designed a series of experimental demonstrations with the dual purpose of making them understand the basic principles of these technologies, and to know the potential of applications to engineering they offer. We assembled these experiments in the laboratory and invited students to pass to get to know them, giving them an explanation in which we focused on the possible range of application of each technique. The response was very good, not only by the number of students who attended the invitation but also by the interest demonstrated by their questions and opinions.

  10. Reducing aeration energy consumption in a large-scale membrane bioreactor: Process simulation and engineering application.

    PubMed

    Sun, Jianyu; Liang, Peng; Yan, Xiaoxu; Zuo, Kuichang; Xiao, Kang; Xia, Junlin; Qiu, Yong; Wu, Qing; Wu, Shijia; Huang, Xia; Qi, Meng; Wen, Xianghua

    2016-04-15

    Reducing the energy consumption of membrane bioreactors (MBRs) is highly important for their wider application in wastewater treatment engineering. Of particular significance is reducing aeration in aerobic tanks to reduce the overall energy consumption. This study proposed an in situ ammonia-N-based feedback control strategy for aeration in aerobic tanks; this was tested via model simulation and through a large-scale (50,000 m(3)/d) engineering application. A full-scale MBR model was developed based on the activated sludge model (ASM) and was calibrated to the actual MBR. The aeration control strategy took the form of a two-step cascaded proportion-integration (PI) feedback algorithm. Algorithmic parameters were optimized via model simulation. The strategy achieved real-time adjustment of aeration amounts based on feedback from effluent quality (i.e., ammonia-N). The effectiveness of the strategy was evaluated through both the model platform and the full-scale engineering application. In the former, the aeration flow rate was reduced by 15-20%. In the engineering application, the aeration flow rate was reduced by 20%, and overall specific energy consumption correspondingly reduced by 4% to 0.45 kWh/m(3)-effluent, using the present practice of regulating the angle of guide vanes of fixed-frequency blowers. Potential energy savings are expected to be higher for MBRs with variable-frequency blowers. This study indicated that the ammonia-N-based aeration control strategy holds promise for application in full-scale MBRs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Some cases in applications of nanotechnology to food and agricultural systems

    USDA-ARS?s Scientific Manuscript database

    Food nanotechnology is an emerging technology. Many scientists and engineers have recognized well the potential of nanotechnology to lead all the industries in the 21st century. Even though successful applications of nanotechnology to foods are still limited, some basic concepts based on nano-scale ...

  12. Formalisms for user interface specification and design

    NASA Technical Reports Server (NTRS)

    Auernheimer, Brent J.

    1989-01-01

    The application of formal methods to the specification and design of human-computer interfaces is described. A broad outline of human-computer interface problems, a description of the field of cognitive engineering and two relevant research results, the appropriateness of formal specification techniques, and potential NASA application areas are described.

  13. Fabrication, optimization and characterization of noble silver nanoparticles from sugarcane leaves (Saccharum officinarum) extract for antifungal application

    USDA-ARS?s Scientific Manuscript database

    Metal nanoparticles obtained from green route are gaining significant prominence as a result of their potential applications in nanomedicine and material engineering. Overall metal nanoparticles studied, silver nanoparticles (AgNPs) clutch prominent place in nanoparticles research field. Herein, we ...

  14. Advanced sensors technology survey

    NASA Technical Reports Server (NTRS)

    Cooper, Tommy G.; Costello, David J.; Davis, Jerry G.; Horst, Richard L.; Lessard, Charles S.; Peel, H. Herbert; Tolliver, Robert

    1992-01-01

    This project assesses the state-of-the-art in advanced or 'smart' sensors technology for NASA Life Sciences research applications with an emphasis on those sensors with potential applications on the space station freedom (SSF). The objectives are: (1) to conduct literature reviews on relevant advanced sensor technology; (2) to interview various scientists and engineers in industry, academia, and government who are knowledgeable on this topic; (3) to provide viewpoints and opinions regarding the potential applications of this technology on the SSF; and (4) to provide summary charts of relevant technologies and centers where these technologies are being developed.

  15. Augmented reality application for industrial non-destructive inspection training

    NASA Astrophysics Data System (ADS)

    Amza, Catalin Gheorghe; Zapciu, Aurelian; Teodorescu, Octav

    2018-02-01

    Such a technology - Augmented Reality (AR) has great potential of use, especially for training purposes of new operators on using expensive equipment. In this context, the paper presents an augmented reality training system developed for phased-array ultrasonic non-destructive testing (NDT) equipment. The application has been developed using Unity 5.6.0 game-engine platform integrated with Vuforia sdk toolkit for devices with Android operating system. The test results performed by several NDT operators showed good results, thus proving the potential of using the application in the industrial field.

  16. Expert system prototype developments for NASA-KSC business and engineering applications

    NASA Technical Reports Server (NTRS)

    Ragusa, James M.; Gonzalez, Avelino J.

    1988-01-01

    Prototype expert systems developed for a variety of NASA projects in the business/management and engineering domains are discussed. Business-related problems addressed include an assistant for simulating launch vehicle processing, a plan advisor for the acquisition of automated data processing equipment, and an expert system for the identification of customer requirements. Engineering problems treated include an expert system for detecting potential ignition sources in LOX and gaseous-oxygen transportation systems and an expert system for hazardous-gas detection.

  17. Tungsten fiber reinforced superalloys: A status review

    NASA Technical Reports Server (NTRS)

    Petrasek, D. W.; Signorelli, R. A.

    1981-01-01

    Improved performance of heat engines is largely dependent upon maximum cycle temperatures. Tungsten fiber reinforced superalloys (TFRS) are the first of a family of high temperature composites that offer the potential for significantly raising hot component operating temperatures and thus leading to improved heat engine performance. This status review of TFRS research emphasizes the promising property data developed to date, the status of TFRS composite airfoil fabrication technology, and the areas requiring more attention to assure their applicability to hot section components of aircraft gas turbine engines.

  18. Future fuels and engines for railroad locomotives. Volume 1: Summary

    NASA Technical Reports Server (NTRS)

    Liddle, S. G.; Bonzo, B. B.; Purohit, G. P.; Stallkamp, J. A.

    1981-01-01

    The potential for reducing the dependence of railroads on petroleum fuel, particularly Diesel No. 2 was investigated. Two approaches are studied: (1) to determine how the use of Diesel No. 2 can be reduced through increased efficiency and conservation, and (2) to use fuels other than Diesel No. 2 both in Diesel and other types of engines. Because synthetic hydrocarbon fuels are particularly suited to medium speed diesel engines, the first commercial application of these fuels may be by the railroad industry.

  19. Fiber reinforced superalloys

    NASA Technical Reports Server (NTRS)

    Petrasek, Donald W.; Signorelli, Robert A.; Caulfield, Thomas; Tien, John K.

    1987-01-01

    Improved performance of heat engines is largely dependent upon maximum cycle temperatures. Tungsten fiber reinforced superalloys (TFRS) are the first of a family of high temperature composites that offer the potential for significantly raising hot component operating temperatures and thus leading to improved heat engine performance. This status review of TFRS research emphasizes the promising property data developed to date, the status of TFRS composite airfoil fabrication technology, and the areas requiring more attention to assure their applicability to hot section components of aircraft gas turbine engines.

  20. Development and Application of 3D Printed Mesoreactors in Chemical Engineering Education

    ERIC Educational Resources Information Center

    Tabassum, Tahseen; Iloska, Marija; Scuereb, Daniel; Taira, Noriko; Jin, Chongguang; Zaitsev, Vladimir; Afshar, Fara; Kim, Taejin

    2018-01-01

    3D printing technology has an enormous potential to apply to chemical engineering education. In this paper, we describe several designs of 3D printed mesoreactors (Y-shape, T-shape, and Long channel shape) using the following steps: reactor sketching, CAD modeling, and reactor printing. With a focus on continuous plug flow mesoreactors (PFRs, i.d.…

  1. Issues related to durability and protection affecting the acceptance and use of engineered wood composites in Europe

    Treesearch

    Mark Hughes; Jerrold E. Winandy

    2007-01-01

    Engineered wood composites (EWC) offer significant potential in applications in the built environment, ranging from domestic dwellings to bridges and public buildings. Nevertheless, EWCs, which include products such as glulam, laminated veneer lumber, oriented stand-board, and plywood enjoy a relatively small market share of total wood-based material production and...

  2. Summary of Research 1998, Department of Mechanical Engineering.

    DTIC Science & Technology

    1999-08-01

    thermoacoustic behavior in strong zero-mean oscillatory flows with potential application to the design of heat exchangers in thermoacoustic engines...important feature in the thermal characterization of microtubes , which are to be used in microheat exchangers . DoD KEY TECHNOLOGY AREA: Modeling and...Simulation KEYWORDS: Laminar Duct Flows, Convection and Conduction Heat Transfer, Axial Conduction, Micro- heat Exchang - ers DEVELOPMENT AND CALIBRATION

  3. [Neural engineering and neural prostheses].

    PubMed

    Gao, Shang-Kai; Zhang, Zhi-Guang; Gao, Xiao-Rong; Hong, Bo; Yang, Fu-Sheng

    2006-03-01

    The motivation of the brain-computer interface (BCI) research and its potential applications are introduced in this paper. Some of the problems in BCI-based medical device developments are also discussed.

  4. Fabrication of novel high surface area mushroom gilled fibers and their effects on human adipose derived stem cells under pulsatile fluid flow for tissue engineering applications.

    PubMed

    Tuin, Stephen A; Pourdeyhimi, Behnam; Loboa, Elizabeth G

    2016-05-01

    The fabrication and characterization of novel high surface area hollow gilled fiber tissue engineering scaffolds via industrially relevant, scalable, repeatable, high speed, and economical nonwoven carding technology is described. Scaffolds were validated as tissue engineering scaffolds using human adipose derived stem cells (hASC) exposed to pulsatile fluid flow (PFF). The effects of fiber morphology on the proliferation and viability of hASC, as well as effects of varied magnitudes of shear stress applied via PFF on the expression of the early osteogenic gene marker runt related transcription factor 2 (RUNX2) were evaluated. Gilled fiber scaffolds led to a significant increase in proliferation of hASC after seven days in static culture, and exhibited fewer dead cells compared to pure PLA round fiber controls. Further, hASC-seeded scaffolds exposed to 3 and 6dyn/cm(2) resulted in significantly increased mRNA expression of RUNX2 after one hour of PFF in the absence of soluble osteogenic induction factors. This is the first study to describe a method for the fabrication of high surface area gilled fibers and scaffolds. The scalable manufacturing process and potential fabrication across multiple nonwoven and woven platforms makes them promising candidates for a variety of applications that require high surface area fibrous materials. We report here for the first time the successful fabrication of novel high surface area gilled fiber scaffolds for tissue engineering applications. Gilled fibers led to a significant increase in proliferation of human adipose derived stem cells after one week in culture, and a greater number of viable cells compared to round fiber controls. Further, in the absence of osteogenic induction factors, gilled fibers led to significantly increased mRNA expression of an early marker for osteogenesis after exposure to pulsatile fluid flow. This is the first study to describe gilled fiber fabrication and their potential for tissue engineering applications. The repeatable, industrially scalable, and versatile fabrication process makes them promising candidates for a variety of scaffold-based tissue engineering applications. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  5. Biomaterials and bioengineering tomorrow’s healthcare

    PubMed Central

    Bhat, Sumrita; Kumar, Ashok

    2013-01-01

    Biomaterials are being used for the healthcare applications from ancient times. But subsequent evolution has made them more versatile and has increased their utility. Biomaterials have revolutionized the areas like bioengineering and tissue engineering for the development of novel strategies to combat life threatening diseases. Together with biomaterials, stem cell technology is also being used to improve the existing healthcare facilities. These concepts and technologies are being used for the treatment of different diseases like cardiac failure, fractures, deep skin injuries, etc. Introduction of nanomaterials on the other hand is becoming a big hope for a better and an affordable healthcare. Technological advancements are underway for the development of continuous monitoring and regulating glucose levels by the implantation of sensor chips. Lab-on-a-chip technology is expected to modernize the diagnostics and make it more easy and regulated. Other area which can improve the tomorrow’s healthcare is drug delivery. Micro-needles have the potential to overcome the limitations of conventional needles and are being studied for the delivery of drugs at different location in human body. There is a huge advancement in the area of scaffold fabrication which has improved the potentiality of tissue engineering. Most emerging scaffolds for tissue engineering are hydrogels and cryogels. Dynamic hydrogels have huge application in tissue engineering and drug delivery. Furthermore, cryogels being supermacroporous allow the attachment and proliferation of most of the mammalian cell types and have shown application in tissue engineering and bioseparation. With further developments we expect these technologies to hit the market in near future which can immensely improve the healthcare facilities. PMID:23628868

  6. Engineering growth factors for regenerative medicine applications.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mitchell, Aaron C.; Briquez, Priscilla S.; Hubbell, Jeffrey A.

    Growth factors are important morphogenetic proteins that instruct cell behavior and guide tissue repair and renewal. Although their therapeutic potential holds great promise in regenerative medicine applications, translation of growth factors into clinical treatments has been hindered by limitations including poor protein stability, low recombinant expression yield, and suboptimal efficacy. This review highlights current tools, technologies, and approaches to design integrated and effective growth factor-based therapies for regenerative medicine applications. The first section describes rational and combinatorial protein engineering approaches that have been utilized to improve growth factor stability, expression yield, biodistribution, and serum half-life, or alter their cell traffickingmore » behavior or receptor binding affinity. The second section highlights elegant biomaterial-based systems, inspired by the natural extracellular matrix milieu, that have been developed for effective spatial and temporal delivery of growth factors to cell surface receptors. Although appearing distinct, these two approaches are highly complementary and involve principles of molecular design and engineering to be considered in parallel when developing optimal materials for clinical applications.« less

  7. Engineering Data Compendium. Human Perception and Performance, Volume 1

    NASA Technical Reports Server (NTRS)

    Boff, Kenneth R. (Editor); Lincoln, Janet E. (Editor)

    1988-01-01

    The concept underlying the Engineering Data Compendium was the product an R and D program (Integrated Perceptual Information for Designers project) aimed at facilitating the application of basic research findings in human performance to the design of military crew systems. The principal objective was to develop a workable strategy for: (1) identifying and distilling information of potential value to system design from existing research literature, and (2) presenting this technical information in a way that would aid its accessibility, interpretability, and applicability by system designers. The present four volumes of the Engineering Data Compendium represent the first implementation of this strategy. This is Volume 1, which contains sections on Visual Acquisition of Information, Auditory Acquisition of Information, and Acquisition of Information by Other Senses.

  8. Engineering Data Compendium. Human Perception and Performance, Volume 2

    NASA Technical Reports Server (NTRS)

    Boff, Kenneth R. (Editor); Lincoln, Janet E. (Editor)

    1988-01-01

    The concept underlying the Engineering Data Compendium was the product of a Research and Development program (Integrated Perceptual Information for Designers project) aimed at facilitating the application of basic research findings in human performance to the design of military crew systems. The principal objective was to develop a workable strategy for: (1) identifying and distilling information of potential value to system design from existing research literature, and (2) presenting this technical information in a way that would aid its accessibility, interpretability, and applicability by system designers. The present volumes of the Engineering Data Compendium represent the first implementation of this strategy. This is Volume 2, which contains sections on Information Storage and Retrieval, Spatial Awareness, Perceptual Organization, and Attention and Allocation of Resources.

  9. Engineering data compendium. Human perception and performance, volume 3

    NASA Technical Reports Server (NTRS)

    Boff, Kenneth R. (Editor); Lincoln, Janet E. (Editor)

    1988-01-01

    The concept underlying the Engineering Data Compendium was the product of a research and development program (Integrated Perceptual Information for Designers project) aimed at facilitating the application of basic research findings in human performance to the design of military crew systems. The principal objective was to develop a workable strategy for: (1) identifying and distilling information of potential value to system design from existing research literature, and (2) presenting this technical information in a way that would aid its accessibility, interpretability, and applicability by system designers. The present four volumes of the Engineering Data Compendium represent the first implementation of this strategy. This is Volume 3, containing sections on Human Language Processing, Operator Motion Control, Effects of Environmental Stressors, Display Interfaces, and Control Interfaces (Real/Virtual).

  10. Engineering data compendium. Human perception and performance. User's guide

    NASA Technical Reports Server (NTRS)

    Boff, Kenneth R. (Editor); Lincoln, Janet E. (Editor)

    1988-01-01

    The concept underlying the Engineering Data Compendium was the product of a research and development program (Integrated Perceptual Information for Designers project) aimed at facilitating the application of basic research findings in human performance to the design and military crew systems. The principal objective was to develop a workable strategy for: (1) identifying and distilling information of potential value to system design from the existing research literature, and (2) presenting this technical information in a way that would aid its accessibility, interpretability, and applicability by systems designers. The present four volumes of the Engineering Data Compendium represent the first implementation of this strategy. This is the first volume, the User's Guide, containing a description of the program and instructions for its use.

  11. Search without Boundaries Using Simple APIs

    USGS Publications Warehouse

    Tong, Qi

    2009-01-01

    The U.S. Geological Survey (USGS) Library, where the author serves as the digital services librarian, is increasingly challenged to make it easier for users to find information from many heterogeneous information sources. Information is scattered throughout different software applications (i.e., library catalog, federated search engine, link resolver, and vendor websites), and each specializes in one thing. How could the library integrate the functionalities of one application with another and provide a single point of entry for users to search across? To improve the user experience, the library launched an effort to integrate the federated search engine into the library's intranet website. The result is a simple search box that leverages the federated search engine's built-in application programming interfaces (APIs). In this article, the author describes how this project demonstrated the power of APIs and their potential to be used by other enterprise search portals inside or outside of the library.

  12. The potential of nanofibers in tissue engineering and stem cell therapy.

    PubMed

    Gholizadeh-Ghaleh Aziz, Shiva; Gholizadeh-Ghaleh Aziz, Sara; Akbarzadeh, Abolfazl

    2016-08-01

    Electrospinning is a technique in which materials in solution are shaped into continuous nano- and micro-sized fibers. Combining stem cells with biomaterial scaffolds and nanofibers affords a favorable approach for bone tissue engineering, stem cell growth and transfer, ocular surface reconstruction, and treatment of congenital corneal diseases. This review seeks to describe the current examples of the use of scaffolds in stem cell therapy. Stem cells are classified as adult or embryonic stem (ES) cells, and the advantages and drawbacks of each group are detailed. The nanofibers and scaffolds are further classified in Tables I and II , which describe specific examples from the literature. Finally, the current applications of biomaterial scaffolds containing stem cells for tissue engineering applications are presented. Overall, this review seeks to give an overview of the biomaterials available for use in combination with stem cells, and the application of nanofibers in stem cell therapy.

  13. Tissue engineering and regenerative medicine: concepts for clinical application.

    PubMed

    Atala, Anthony

    2004-01-01

    Patients suffering from diseased and injured organs may be treated with transplanted organs. However, there is a severe shortage of donor organs that is worsening yearly given the aging population. Scientists in the field of regenerative medicine and tissue engineering apply the principles of cell transplantation, material science, and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Therapeutic cloning, where the nucleus from a donor cell is transferred into an enucleated oocyte in order to extract pluripotent embryonic stem cells, offers a potentially limitless source of cells for tissue engineering applications. The stem cell field is also advancing rapidly, opening new options for therapy. This paper reviews recent advances that have occurred in regenerative medicine and describes applications of these new technologies that may offer novel therapies for patients with end-stage organ failure.

  14. Design and evaluation of fluidized bed heat recovery for diesel engine systems

    NASA Technical Reports Server (NTRS)

    Hamm, J. R.; Newby, R. A.; Vidt, E. J.; Lippert, T. E.

    1985-01-01

    The potential of utilizing fluidized bed heat exchangers in place of conventional counter-flow heat exchangers for heat recovery from adiabatic diesel engine exhaust gas streams was studied. Fluidized bed heat recovery systems were evaluated in three different heavy duty transport applications: (1) heavy duty diesel truck; (2) diesel locomotives; and (3) diesel marine pushboat. The three applications are characterized by differences in overall power output and annual utilization. For each application, the exhaust gas source is a turbocharged-adiabatic diesel core. Representative subposed exhaust gas heat utilization power cycles were selected for conceptual design efforts including design layouts and performance estimates for the fluidized bed heat recovery heat exchangers. The selected power cycles were: organic rankine with RC-1 working fluid, turbocompound power turbine with steam injection, and stirling engine. Fuel economy improvement predictions are used in conjunction with capital cost estimates and fuel price data to determine payback times for the various cases.

  15. Engineered passive bioreactive barriers: risk-managing the legacy of industrial soil and groundwater pollution.

    PubMed

    Kalin, Robert M

    2004-06-01

    Permeable reactive barriers are a technology that is one decade old, with most full-scale applications based on abiotic mechanisms. Though there is extensive literature on engineered bioreactors, natural biodegradation potential, and in situ remediation, it is only recently that engineered passive bioreactive barrier technology is being considered at the commercial scale to manage contaminated soil and groundwater risks. Recent full-scale studies are providing the scientific confidence in our understanding of coupled microbial (and genetic), hydrogeologic, and geochemical processes in this approach and have highlighted the need to further integrate engineering and science tools.

  16. Small Engine Component Technology (SECT)

    NASA Technical Reports Server (NTRS)

    Early, M.; Dawson, R.; Zeiner, P.; Turk, M.; Benn, K.

    1986-01-01

    A study of small gas turbine engines was conducted to identify high payoff technologies for year-2000 engines and to define companion technology plans. The study addressed engines in the 186 to 746 KW (250 to 1000 shp) or equivalent thrust range for rotorcraft, commuter (turboprop), cruise missile (turbojet), and APU applications. The results show that aggressive advancement of high payoff technologies can produce significant benefits, including reduced SFC, weight, and cost for year-2000 engines. Mission studies for these engines show potential fuel burn reductions of 22 to 71 percent. These engine benefits translate into reductions in rotorcraft and commuter aircraft direct operating costs (DOC) of 7 to 11 percent, and in APU-related DOCs of 37 to 47 percent. The study further shows that cruise missile range can be increased by as much as 200 percent (320 percent with slurry fuels) for a year-2000 missile-turbojet system compared to a current rocket-powered system. The high payoff technologies were identified and the benefits quantified. Based on this, technology plans were defined for each of the four engine applications as recommended guidelines for further NASA research and technology efforts to establish technological readiness for the year 2000.

  17. Microbially derived biosensors for diagnosis, monitoring and epidemiology.

    PubMed

    Chang, Hung-Ju; Voyvodic, Peter L; Zúñiga, Ana; Bonnet, Jérôme

    2017-09-01

    Living cells have evolved to detect and process various signals and can self-replicate, presenting an attractive platform for engineering scalable and affordable biosensing devices. Microbes are perfect candidates: they are inexpensive and easy to manipulate and store. Recent advances in synthetic biology promise to streamline the engineering of microbial biosensors with unprecedented capabilities. Here we review the applications of microbially-derived biosensors with a focus on environmental monitoring and healthcare applications. We also identify critical challenges that need to be addressed in order to translate the potential of synthetic microbial biosensors into large-scale, real-world applications. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  18. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Farrell, John T; Kelly, Kenneth J; Duran, Adam W

    Range-extended electric vehicle (EV) technology can be a viable option for reducing fuel consumption from medium-duty (MD) and heavy-duty (HD) engines by approximately 50 percent or more. Such engines have wide variations in use and duty cycles, however, and identifying the vocations/duty cycles most suitable for range-extended applications is vital for maximizing the potential benefits. This presentation provides information about NREL's research on range-extended EV technologies, with a focus on NREL's real-world data collection and analysis approach to identifying the vocations/duty cycles best suited for range-extender applications and to help guide related powertrain optimization and design requirements. The presentation alsomore » details NREL's drive cycle development process as it pertains to package delivery applications.« less

  19. Potential applications of three-dimensional structure of silk fibroin/poly(ester-urethane) urea nanofibrous scaffold in heart valve tissue engineering

    NASA Astrophysics Data System (ADS)

    Du, Juan; Zhu, Tonghe; Yu, Haiyan; Zhu, Jingjing; Sun, Changbing; Wang, Jincheng; Chen, Sihao; Wang, Jihu; Guo, Xuran

    2018-07-01

    Tissue engineering heart valves (TEHV) are thought to have many advantages in low immunogenicity, good histocompatibility, excellent mechanical properties. In this paper, we reported the fabrication and characterization of a novel composite nanofibrous scaffold consisting of silk fibroin (SF) and poly(ester-urethane) urea (LDI-PEUU) by using electrospinning. Chemical and physical properties of scaffolds were evaluated using scanning electron microscopy, attenuated total reflectance Fourier transform infrared, X-ray diffraction, contact angle measurement, thermogravimetric analysis, biodegradation test and tensile strength analysis. We determined that the composite scaffolds supported the growth of human umbilical vein endothelial cell (HUVEC). The results of cell proliferation and cell morphology indicate that SF/LDI-PEUU nanofibers promoted cell viability, which supporting the application in tissue engineering. All results clarified that SF/LDI-PEUU (40:60) nanofibrous scaffolds meet the required specifications for tissue engineering and could be used as a promising construct for heart valve tissue engineering.

  20. Skeletal Muscle Tissue Engineering: Methods to Form Skeletal Myotubes and Their Applications

    PubMed Central

    Ostrovidov, Serge; Hosseini, Vahid; Ahadian, Samad; Fujie, Toshinori; Parthiban, Selvakumar Prakash; Ramalingam, Murugan; Bae, Hojae; Kaji, Hirokazu

    2014-01-01

    Skeletal muscle tissue engineering (SMTE) aims to repair or regenerate defective skeletal muscle tissue lost by traumatic injury, tumor ablation, or muscular disease. However, two decades after the introduction of SMTE, the engineering of functional skeletal muscle in the laboratory still remains a great challenge, and numerous techniques for growing functional muscle tissues are constantly being developed. This article reviews the recent findings regarding the methodology and various technical aspects of SMTE, including cell alignment and differentiation. We describe the structure and organization of muscle and discuss the methods for myoblast alignment cultured in vitro. To better understand muscle formation and to enhance the engineering of skeletal muscle, we also address the molecular basics of myogenesis and discuss different methods to induce myoblast differentiation into myotubes. We then provide an overview of different coculture systems involving skeletal muscle cells, and highlight major applications of engineered skeletal muscle tissues. Finally, potential challenges and future research directions for SMTE are outlined. PMID:24320971

  1. Adipose-Derived Stem Cell Delivery for Adipose Tissue Engineering: Current Status and Potential Applications in a Tissue Engineering Chamber Model.

    PubMed

    Zhan, Weiqing; Tan, Shaun S; Lu, Feng

    2016-08-01

    In reconstructive surgery, there is a clinical need for adequate implants to repair soft tissue defects caused by traumatic injury, tumor resection, or congenital abnormalities. Adipose tissue engineering may provide answers to this increasing demand. This study comprehensively reviews current approaches to adipose tissue engineering, detailing different cell carriers under investigation, with a special focus on the application of adipose-derived stem cells (ASCs). ASCs act as building blocks for new tissue growth and as modulators of the host response. Recent studies have also demonstrated that the implantation of a hollow protected chamber, combined with a vascular pedicle within the fat flaps provides blood supply and enables the growth of large-volume of engineered soft tissue. Conceptually, it would be of value to co-regulate this unique chamber model with adipose-derived stem cells to obtain a greater volume of soft tissue constructs for clinical use. Our review provides a cogent update on these advances and details the generation of possible fat substitutes.

  2. Fn3 proteins engineered to recognize tumor biomarker mesothelin internalize upon binding

    PubMed Central

    Sirois, Allison R.; Deny, Daniela A.; Baierl, Samantha R.; George, Katia S.

    2018-01-01

    Mesothelin is a cell surface protein that is overexpressed in numerous cancers, including breast, ovarian, lung, liver, and pancreatic tumors. Aberrant expression of mesothelin has been shown to promote tumor progression and metastasis through interaction with established tumor biomarker CA125. Therefore, molecules that specifically bind to mesothelin have potential therapeutic and diagnostic applications. However, no mesothelin-targeting molecules are currently approved for routine clinical use. While antibodies that target mesothelin are in development, some clinical applications may require a targeting molecule with an alternative protein fold. For example, non-antibody proteins are more suitable for molecular imaging and may facilitate diverse chemical conjugation strategies to create drug delivery complexes. In this work, we engineered variants of the fibronectin type III domain (Fn3) non-antibody protein scaffold to bind to mesothelin with high affinity, using directed evolution and yeast surface display. Lead engineered Fn3 variants were solubly produced and purified from bacterial culture at high yield. Upon specific binding to mesothelin on human cancer cell lines, the engineered Fn3 proteins internalized and co-localized to early endosomes. To our knowledge, this is the first report of non-antibody proteins engineered to bind mesothelin. The results validate that non-antibody proteins can be engineered to bind to tumor biomarker mesothelin, and encourage the continued development of engineered variants for applications such as targeted diagnostics and therapeutics. PMID:29738555

  3. Tissue engineering, stem cells, cloning, and parthenogenesis: new paradigms for therapy

    PubMed Central

    Hipp, Jason; Atala, Anthony

    2004-01-01

    Patients suffering from diseased and injured organs may be treated with transplanted organs. However, there is a severe shortage of donor organs which is worsening yearly due to the aging population. Scientists in the field of tissue engineering apply the principles of cell transplantation, materials science, and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Both therapeutic cloning (nucleus from a donor cell is transferred into an enucleated oocyte), and parthenogenesis (oocyte is activated and stimulated to divide), permit extraction of pluripotent embryonic stem cells, and offer a potentially limitless source of cells for tissue engineering applications. The stem cell field is also advancing rapidly, opening new options for therapy. The present article reviews recent progress in tissue engineering and describes applications of these new technologies that may offer novel therapies for patients with end-stage organ failure. PMID:15588286

  4. Modern technologies for retinal scanning and imaging: an introduction for the biomedical engineer

    PubMed Central

    2014-01-01

    This review article is meant to help biomedical engineers and nonphysical scientists better understand the principles of, and the main trends in modern scanning and imaging modalities used in ophthalmology. It is intended to ease the communication between physicists, medical doctors and engineers, and hopefully encourage “classical” biomedical engineers to generate new ideas and to initiate projects in an area which has traditionally been dominated by optical physics. Most of the methods involved are applicable to other areas of biomedical optics and optoelectronics, such as microscopic imaging, spectroscopy, spectral imaging, opto-acoustic tomography, fluorescence imaging etc., all of which are with potential biomedical application. Although all described methods are novel and important, the emphasis of this review has been placed on three technologies introduced in the 1990’s and still undergoing vigorous development: Confocal Scanning Laser Ophthalmoscopy, Optical Coherence Tomography, and polarization-sensitive retinal scanning. PMID:24779618

  5. Tissue engineering, stem cells, cloning, and parthenogenesis: new paradigms for therapy.

    PubMed

    Hipp, Jason; Atala, Anthony

    2004-12-08

    : BACKGROUND: Patients suffering from diseased and injured organs may be treated with transplanted organs. However, there is a severe shortage of donor organs which is worsening yearly due to the aging population. Scientists in the field of tissue engineering apply the principles of cell transplantation, materials science, and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Both therapeutic cloning (nucleus from a donor cell is transferred into an enucleated oocyte), and parthenogenesis (oocyte is activated and stimulated to divide), permit extraction of pluripotent embryonic stem cells, and offer a potentially limitless source of cells for tissue engineering applications. The stem cell field is also advancing rapidly, opening new options for therapy. The present article reviews recent progress in tissue engineering and describes applications of these new technologies that may offer novel therapies for patients with end-stage organ failure.

  6. Solar-Powered Electric Propulsion Systems: Engineering and Applications

    NASA Technical Reports Server (NTRS)

    Stearns, J. W.; Kerrisk, D. J.

    1966-01-01

    Lightweight, multikilowatt solar power arrays in conjunction with electric propulsion offer potential improvements to space exploration, extending the usefulness of existing launch vehicles to higher-energy missions. Characteristics of solar-powered electric propulsion missions are outlined, and preliminary performance estimates are shown. Spacecraft system engineering is discussed with respect to parametric trade-offs in power and propulsion system design. Relationships between mission performance and propulsion system performance are illustrated. The present state of the art of electric propulsion systems is reviewed and related to the mission requirements identified earlier. The propulsion system design and test requirements for a mission spacecraft are identified and discussed. Although only ion engine systems are currently available, certain plasma propulsion systems offer some advantages in over-all system design. These are identified, and goals are set for plasma-thrustor systems to make them competitive with ion-engine systems for mission applications.

  7. Delivery of small molecules for bone regenerative engineering: preclinical studies and potential clinical applications

    PubMed Central

    Laurencin, Cato T.; Ashe, Keshia M.; Henry, Nicole; Kan, Ho Man; Lo, Kevin W-H.

    2014-01-01

    Stimulation of bone regeneration using growth factors is a promising approach for musculoskeletal regenerative engineering. Common limitations with protein growth factors are high manufacturing costs, protein instability, contamination issues, and unwanted immunogenic responses of the host. New strategies for bone regeneration that obviate these problems can have a significant impact on the treatment of skeletal injury and diseases. Over the past decade, a large number of small molecules with the potential of regenerating skeletal tissue have been reported in the literature. Here, we review this literature, paying specific attention to the prospects for small molecule-based bone-regenerative engineering. We also review the preclinical study of small molecules associated with bone regeneration. PMID:24508820

  8. Summary of NASA research on thermal-barrier coatings

    NASA Technical Reports Server (NTRS)

    Stepka, F. S.; Liebert, C. H.; Stecura, S.

    1977-01-01

    A durable, two-layer, plasma-sprayed coating consisting of a ceramic layer over a metallic layer was developed that has the potential of insulating hot engine parts and thereby reducing metal temperatures and coolant flow requirements and/or permitting use of less costly and complex cooling configurations and materials. The investigations evaluated the reflective and insulative capability, microstructure, and durability of several coating materials on flat metal specimens, a combustor liner, and turbine vanes and blades. In addition, the effect on the aerodynamic performance of a coated turbine vane was measured. The tests were conducted in furnaces, cascades, hot-gas rigs, an engine combustor, and a research turbojet engine. Summaries of current research related to the coating and potential applications for the coating are included.

  9. Road to the future of systems biotechnology: CRISPR-Cas-mediated metabolic engineering for recombinant protein production.

    PubMed

    Roointan, Amir; Morowvat, Mohammad Hossein

    The rising potential for CRISPR-Cas-mediated genome editing has revolutionized our strategies in basic and practical bioengineering research. It provides a predictable and precise method for genome modification in a robust and reproducible fashion. Emergence of systems biotechnology and synthetic biology approaches coupled with CRISPR-Cas technology could change the future of cell factories to possess some new features which have not been found naturally. We have discussed the possibility and versatile potentials of CRISPR-Cas technology for metabolic engineering of a recombinant host for heterologous protein production. We describe the mechanisms involved in this metabolic engineering approach and present the diverse features of its application in biotechnology and protein production.

  10. Silk fibroin as biomaterial for bone tissue engineering.

    PubMed

    Melke, Johanna; Midha, Swati; Ghosh, Sourabh; Ito, Keita; Hofmann, Sandra

    2016-02-01

    Silk fibroin (SF) is a fibrous protein which is produced mainly by silkworms and spiders. Its unique mechanical properties, tunable biodegradation rate and the ability to support the differentiation of mesenchymal stem cells along the osteogenic lineage, have made SF a favorable scaffold material for bone tissue engineering. SF can be processed into various scaffold forms, combined synergistically with other biomaterials to form composites and chemically modified, which provides an impressive toolbox and allows SF scaffolds to be tailored to specific applications. This review discusses and summarizes recent advancements in processing SF, focusing on different fabrication and functionalization methods and their application to grow bone tissue in vitro and in vivo. Potential areas for future research, current challenges, uncertainties and gaps in knowledge are highlighted. Silk fibroin is a natural biomaterial with remarkable biomedical and mechanical properties which make it favorable for a broad range of bone tissue engineering applications. It can be processed into different scaffold forms, combined synergistically with other biomaterials to form composites and chemically modified which provides a unique toolbox and allows silk fibroin scaffolds to be tailored to specific applications. This review discusses and summarizes recent advancements in processing silk fibroin, focusing on different fabrication and functionalization methods and their application to grow bone tissue in vitro and in vivo. Potential areas for future research, current challenges, uncertainties and gaps in knowledge are highlighted. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  11. Expanding Metabolic Engineering Algorithms Using Feasible Space and Shadow Price Constraint Modules

    PubMed Central

    Tervo, Christopher J.; Reed, Jennifer L.

    2014-01-01

    While numerous computational methods have been developed that use genome-scale models to propose mutants for the purpose of metabolic engineering, they generally compare mutants based on a single criteria (e.g., production rate at a mutant’s maximum growth rate). As such, these approaches remain limited in their ability to include multiple complex engineering constraints. To address this shortcoming, we have developed feasible space and shadow price constraint (FaceCon and ShadowCon) modules that can be added to existing mixed integer linear adaptive evolution metabolic engineering algorithms, such as OptKnock and OptORF. These modules allow strain designs to be identified amongst a set of multiple metabolic engineering algorithm solutions that are capable of high chemical production while also satisfying additional design criteria. We describe the various module implementations and their potential applications to the field of metabolic engineering. We then incorporated these modules into the OptORF metabolic engineering algorithm. Using an Escherichia coli genome-scale model (iJO1366), we generated different strain designs for the anaerobic production of ethanol from glucose, thus demonstrating the tractability and potential utility of these modules in metabolic engineering algorithms. PMID:25478320

  12. Injectable hydrogels for cartilage and bone tissue engineering

    PubMed Central

    Liu, Mei; Zeng, Xin; Ma, Chao; Yi, Huan; Ali, Zeeshan; Mou, Xianbo; Li, Song; Deng, Yan; He, Nongyue

    2017-01-01

    Tissue engineering has become a promising strategy for repairing damaged cartilage and bone tissue. Among the scaffolds for tissue-engineering applications, injectable hydrogels have demonstrated great potential for use as three-dimensional cell culture scaffolds in cartilage and bone tissue engineering, owing to their high water content, similarity to the natural extracellular matrix (ECM), porous framework for cell transplantation and proliferation, minimal invasive properties, and ability to match irregular defects. In this review, we describe the selection of appropriate biomaterials and fabrication methods to prepare novel injectable hydrogels for cartilage and bone tissue engineering. In addition, the biology of cartilage and the bony ECM is also summarized. Finally, future perspectives for injectable hydrogels in cartilage and bone tissue engineering are discussed. PMID:28584674

  13. Recent insights on applications of pullulan in tissue engineering.

    PubMed

    Singh, Ram Sarup; Kaur, Navpreet; Rana, Vikas; Kennedy, John F

    2016-11-20

    Tissue engineering is a recently emerging line of act which assists the regeneration of damaged tissues, unable to self-repair themselves and in turn, enhances the natural healing potential of patients. The repair of injured tissue can be induced with the help of some artificially created polymer scaffolds for successful tissue regeneration. The pullulan composite scaffolds can be used to enhance the proliferation and differentiation of cells for tissue regeneration. The unique pattern of pullulan with α-(1→4) and α-(1→6) linkages along with the presence of nine hydroxyl groups on its surface, endows the polymer with distinctive physical features required for tissue engineering. Pullulan can be used for vascular engineering, bone repair and skin tissue engineering. Pullulan composite scaffolds can also be used for treatment of injured femoral condyle bone, skull bone and full thickness skin wound of murine models, transversal mandibular and tibial osteotomy in goat, etc. This review article highlights the latest developments on applications of pullulan and its derivatives in tissue engineering. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Artificial Intelligence for Command and Control

    DTIC Science & Technology

    1988-05-15

    complexity of information and are a very active current research area. Some of the important unresolved frame -related issues are control issues , such as...indepth analysis of the combat engineer’s decisio -mnaking activities. -Specificaly 3 combat engineers-stationed at Fort Bragg, North Carolina (307th...experience. The CETOOLS concept is potentially applicable in any decision- making environment, commercial or government, where plans for actions are

  15. US-Europe Workshop on Impact of Multifunctionality on Damage Evolution in Composite Materials

    DTIC Science & Technology

    2015-09-01

    Inventions (DD882) Scientific Progress See Attachment Technology Transfer Not applicable UNIVERSITY OF ILLINOIS AEROSPACE ENGINEERING...Composite Materials PI: Ioannis Chasiotis Aerospace Engineering University of Illinois at Urbana-Champaign Talbot Lab, 104 S. Wright Street, Urbana, IL...focused on the current state of corporate research in the aerospace industry which is a major potential adopter of multifunctional composites. The two

  16. An overview of aerospace gas turbine technology of relevance to the development of the automotive gas turbine engine

    NASA Technical Reports Server (NTRS)

    Evans, D. G.; Miller, T. J.

    1978-01-01

    Technology areas related to gas turbine propulsion systems with potential for application to the automotive gas turbine engine are discussed. Areas included are: system steady-state and transient performance prediction techniques, compressor and turbine design and performance prediction programs and effects of geometry, combustor technology and advanced concepts, and ceramic coatings and materials technology.

  17. Breast tissue engineering.

    PubMed

    Patrick, Charles W

    2004-01-01

    Tissue engineering has the potential to redefine rehabilitation for the breast cancer patient by providing a translatable strategy that restores the postmastectomy breast mound while concomitantly obviating limitations realized with contemporary reconstructive surgery procedures. The engineering design goal is to provide a sufficient volume of viable fat tissue based on a patient's own cells such that deficits in breast volume can be abrogated. To be sure, adipose tissue engineering is in its infancy, but tremendous strides have been made. Numerous studies attest to the feasibility of adipose tissue engineering. The field is now poised to challenge barriers to clinical translation that are germane to most tissue engineering applications, namely scale-up, large animal model development, and vascularization. The innovative and rapid progress of adipose engineering to date, as well as opportunities for its future growth, is presented.

  18. Chloroplast genomes: diversity, evolution, and applications in genetic engineering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Daniell, Henry; Lin, Choun -Sea; Yu, Ming

    Chloroplasts play a crucial role in sustaining life on earth. The availability of over 800 sequenced chloroplast genomes from a variety of land plants has enhanced our understanding of chloroplast biology, intracellular gene transfer, conservation, diversity, and the genetic basis by which chloroplast transgenes can be engineered to enhance plant agronomic traits or to produce high-value agricultural or biomedical products. In this review, we discuss the impact of chloroplast genome sequences on understanding the origins of economically important cultivated species and changes that have taken place during domestication. Here, we also discuss the potential biotechnological applications of chloroplast genomes.

  19. Chloroplast genomes: diversity, evolution, and applications in genetic engineering

    DOE PAGES

    Daniell, Henry; Lin, Choun -Sea; Yu, Ming; ...

    2016-06-23

    Chloroplasts play a crucial role in sustaining life on earth. The availability of over 800 sequenced chloroplast genomes from a variety of land plants has enhanced our understanding of chloroplast biology, intracellular gene transfer, conservation, diversity, and the genetic basis by which chloroplast transgenes can be engineered to enhance plant agronomic traits or to produce high-value agricultural or biomedical products. In this review, we discuss the impact of chloroplast genome sequences on understanding the origins of economically important cultivated species and changes that have taken place during domestication. Here, we also discuss the potential biotechnological applications of chloroplast genomes.

  20. Recent advances in electrospun nanofibers for wound healing.

    PubMed

    Chen, Shixuan; Liu, Bing; Carlson, Mark A; Gombart, Adrian F; Reilly, Debra A; Xie, Jingwei

    2017-06-01

    Electrospun nanofibers represent a novel class of materials that show great potential in many biomedical applications including biosensing, regenerative medicine, tissue engineering, drug delivery and wound healing. In this work, we review recent advances in electrospun nanofibers for wound healing. This article begins with a brief introduction on the wound, and then discusses the unique features of electrospun nanofibers critical for wound healing. It further highlights recent studies that have used electrospun nanofibers for wound healing applications and devices, including sutures, multifunctional dressings, dermal substitutes, engineered epidermis and full-thickness skin regeneration. Finally, we finish with conclusions and future perspective in this field.

  1. Method for evaluating the reliability of compressor impeller of turbocharger for vehicle application in plateau area

    NASA Astrophysics Data System (ADS)

    Wang, Zheng; Wang, Zengquan; Wang, A.-na; Zhuang, Li; Wang, Jinwei

    2016-10-01

    As turbocharging diesel engines for vehicle application are applied in plateau area, the environmental adaptability of engines has drawn more attention. For the environmental adaptability problem of turbocharging diesel engines for vehicle application, the present studies almost focus on the optimization of performance match between turbocharger and engine, and the reliability problem of turbocharger is almost ignored. The reliability problem of compressor impeller of turbocharger for vehicle application when diesel engines operate in plateau area is studied. Firstly, the rule that the rotational speed of turbocharger changes with the altitude height is presented, and the potential failure modes of compressor impeller are analyzed. Then, the failure behavior models of compressor impeller are built, and the reliability models of compressor impeller operating in plateau area are developed. Finally, the rule that the reliability of compressor impeller changes with the altitude height is studied, the measurements for improving the reliability of the compressor impellers of turbocharger operating in plateau area are given. The results indicate that when the operating speed of diesel engine is certain, the rotational speed of turbocharger increases with the increase of altitude height, and the failure risk of compressor impeller with the failure modes of hub fatigue and blade resonance increases. The reliability of compressor impeller decreases with the increase of altitude height, and it also decreases as the increase of number of the mission profile cycle of engine. The method proposed can not only be used to evaluating the reliability of compressor impeller when diesel engines operate in plateau area but also be applied to direct the structural optimization of compressor impeller.

  2. Molecularly Imprinted Intelligent Scaffolds for Tissue Engineering Applications.

    PubMed

    Neves, Mariana I; Wechsler, Marissa E; Gomes, Manuela E; Reis, Rui L; Granja, Pedro L; Peppas, Nicholas A

    2017-02-01

    The development of molecularly imprinted polymers (MIPs) using biocompatible production methods enables the possibility to further exploit this technology for biomedical applications. Tissue engineering (TE) approaches use the knowledge of the wound healing process to design scaffolds capable of modulating cell behavior and promote tissue regeneration. Biomacromolecules bear great interest for TE, together with the established recognition of the extracellular matrix, as an important source of signals to cells, both promoting cell-cell and cell-matrix interactions during the healing process. This review focuses on exploring the potential of protein molecular imprinting to create bioactive scaffolds with molecular recognition for TE applications based on the most recent approaches in the field of molecular imprinting of macromolecules. Considerations regarding essential components of molecular imprinting technology will be addressed for TE purposes. Molecular imprinting of biocompatible hydrogels, namely based on natural polymers, is also reviewed here. Hydrogel scaffolds with molecular memory show great promise for regenerative therapies. The first molecular imprinting studies analyzing cell adhesion report promising results with potential applications for cell culture systems, or biomaterials for implantation with the capability for cell recruitment by selectively adsorbing desired molecules.

  3. Supercritical phase inversion of starch-poly(epsilon-caprolactone) for tissue engineering applications.

    PubMed

    Duarte, Ana Rita C; Mano, João F; Reis, Rui L

    2010-02-01

    In this work, a starch-based polymer, namely a blend of starch-poly(epsilon-caprolactone) was processed by supercritical assisted phase inversion process. This processing technique has been proposed for the development of 3D structures with potential applications in tissue engineering applications, as scaffolds. The use of carbon dioxide as non-solvent in the phase inversion process leads to the formation of a porous and interconnected structure, dry and free of any residual solvent. Different processing conditions such as pressure (from 80 up to 150 bar) and temperature (45 and 55 degrees C) were studied and the effect on the morphological features of the scaffolds was evaluated by scanning electron microscopy and micro-computed tomography. The mechanical properties of the SPCL scaffolds prepared were also studied. Additionally, in this work, the in vitro biological performance of the scaffolds was studied. Cell adhesion and morphology, viability and proliferation was assessed and the results suggest that the materials prepared are allow cell attachment and promote cell proliferation having thus potential to be used in some for biomedical applications.

  4. A study of education and KSAOs on career entry for product engineers: What employers really want

    NASA Astrophysics Data System (ADS)

    Thornburgh, James

    The purpose of the study was to investigate the ways that employers of product engineers evaluate potential employees' job readiness, and which theories related to the education-work transaction are supported by practice. This study used a mixed methods approach and consisted of a state-wide survey (N=106) and local interviews (N=8). The results of the research indicate that attributes of both the Theory of Individual Differences and Credentialing Theory are present in the hiring practices of product engineers. Consistent with the Theory of Individual Differences, employers indicate they look for evidence of various job-related Knowledge, Skills, Abilities, and Other attributes (KSAOs) and they indicate they are willing to hire applicants who have less than a bachelor's degree. Consistent with Credentialing Theory, employers advertise a formal education minimum which represents only one way that individuals may learn to be an engineer. This study also confirmed prior research that most employers use primarily non-evidence based predictors to evaluate applicants. The primary initial screening predictors were experience, GPA, and major, while the primary finalist selection predictors were unstructured interviews, and applications, followed by structured interviews, job knowledge tests, and work sample test. Contrary to previous findings, this study did not find any major differences between what HR professionals, engineering managers, or other manager look for in terms of qualifications or what predictors they use when evaluating applicants for product engineer positions.

  5. Study of unconventional aircraft engines designed for low energy consumption

    NASA Technical Reports Server (NTRS)

    Neitzel, R. E.; Hirschkron, R.; Johnston, R. P.

    1976-01-01

    A study of unconventional engine cycle concepts, which may offer significantly lower energy consumption than conventional subsonic transport turbofans, is described herein. A number of unconventional engine concepts were identified and parametrically studied to determine their relative fuel-saving potential. Based on results from these studies, regenerative, geared, and variable-boost turbofans, and combinations thereof, were selected along with advanced turboprop cycles for further evaluation and refinement. Preliminary aerodynamic and mechanical designs of these unconventional engine configurations were conducted and mission performance was compared to a conventional, direct-drive turofan reference engine. Consideration is given to the unconventional concepts, and their state of readiness for application. Areas of needed technology advancement are identified.

  6. Analysis and test of insulated components for rotary engine

    NASA Technical Reports Server (NTRS)

    Badgley, Patrick R.; Doup, Douglas; Kamo, Roy

    1989-01-01

    The direct-injection stratified-charge (DISC) rotary engine, while attractive for aviation applications due to its light weight, multifuel capability, and potentially low fuel consumption, has until now required a bulky and heavy liquid-cooling system. NASA-Lewis has undertaken the development of a cooling system-obviating, thermodynamically superior adiabatic rotary engine employing state-of-the-art thermal barrier coatings to thermally insulate engine components. The thermal barrier coating material for the cast aluminum, stainless steel, and ductile cast iron components was plasma-sprayed zirconia. DISC engine tests indicate effective thermal barrier-based heat loss reduction, but call for superior coefficient-of-thermal-expansion matching of materials and better tribological properties in the coatings used.

  7. [Application of silk-based tissue engineering scaffold for tendon / ligament regeneration].

    PubMed

    Hu, Yejun; Le, Huihui; Jin, Zhangchu; Chen, Xiao; Yin, Zi; Shen, Weiliang; Ouyang, Hongwei

    2016-03-01

    Tendon/ligament injury is one of the most common impairments in sports medicine. The traditional treatments of damaged tissue repair are unsatisfactory, especially for athletes, due to lack of donor and immune rejection. The strategy of tissue engineering may break through these limitations, and bring new hopes to tendon/ligament repair, even regeneration. Silk is a kind of natural biomaterials, which has good biocompatibility, wide range of mechanical properties and tunable physical structures; so it could be applied as tendon/ligament tissue engineering scaffolds. The silk-based scaffold has robust mechanical properties; combined with other biological ingredients, it could increase the surface area, promote more cell adhesion and improve the biocompatibility. The potential clinical application of silk-based scaffold has been confirmed by in vivo studies on tendon/ligament repairing, such as anterior cruciate ligament, medial collateral ligament, achilles tendon and rotator cuff. To develop novel biomechanically stable and host integrated tissue engineered tendon/ligament needs more further micro and macro studies, combined with product development and clinical application, which will give new hope to patients with tendon/ligament injury.

  8. Electrical stimulation: a novel tool for tissue engineering.

    PubMed

    Balint, Richard; Cassidy, Nigel J; Cartmell, Sarah H

    2013-02-01

    New advances in tissue engineering are being made through the application of different types of electrical stimuli to influence cell proliferation and differentiation. Developments made in the last decade have allowed us to improve the structure and functionality of tissue-engineered products through the use of growth factors, hormones, drugs, physical stimuli, bioreactor use, and two-dimensional (2-D) and three-dimensional (3-D) artificial extracellular matrices (with various material properties and topography). Another potential type of stimulus is electricity, which is important in the physiology and development of the majority of all human tissues. Despite its great potential, its role in tissue regeneration and its ability to influence cell migration, orientation, proliferation, and differentiation has rarely been considered in tissue engineering. This review highlights the importance of endogenous electrical stimulation, gathering the current knowledge on its natural occurrence and role in vivo, discussing the novel methods of delivering this stimulus and examining its cellular and tissue level effects, while evaluating how the technique could benefit the tissue engineering discipline in the future.

  9. Microbial isoprenoid production: an example of green chemistry through metabolic engineering.

    PubMed

    Maury, Jérôme; Asadollahi, Mohammad A; Møller, Kasper; Clark, Anthony; Nielsen, Jens

    2005-01-01

    Saving energy, cost efficiency, producing less waste, improving the biodegradability of products, potential for producing novel and complex molecules with improved properties, and reducing the dependency on fossil fuels as raw materials are the main advantages of using biotechnological processes to produce chemicals. Such processes are often referred to as green chemistry or white biotechnology. Metabolic engineering, which permits the rational design of cell factories using directed genetic modifications, is an indispensable strategy for expanding green chemistry. In this chapter, the benefits of using metabolic engineering approaches for the development of green chemistry are illustrated by the recent advances in microbial production of isoprenoids, a diverse and important group of natural compounds with numerous existing and potential commercial applications. Accumulated knowledge on the metabolic pathways leading to the synthesis of the principal precursors of isoprenoids is reviewed, and recent investigations into isoprenoid production using engineered cell factories are described.

  10. Performance potential of gas-core and fusion rockets - A mission applications survey.

    NASA Technical Reports Server (NTRS)

    Fishbach, L. H.; Willis, E. A., Jr.

    1971-01-01

    This paper reports an evaluation of the performance potential of five nuclear rocket engines for four mission classes. These engines are: the regeneratively cooled gas-core nuclear rocket; the light bulb gas-core nuclear rocket; the space-radiator cooled gas-core nuclear rocket; the fusion rocket; and an advanced solid-core nuclear rocket which is included for comparison. The missions considered are: earth-to-orbit launch; near-earth space missions; close interplanetary missions; and distant interplanetary missions. For each of these missions, the capabilities of each rocket engine type are compared in terms of payload ratio for the earth launch mission or by the initial vehicle mass in earth orbit for space missions (a measure of initial cost). Other factors which might determine the engine choice are discussed. It is shown that a 60 day manned round trip to Mars is conceivable.-

  11. CHO microRNA engineering is growing up: Recent successes and future challenges☆

    PubMed Central

    Jadhav, Vaibhav; Hackl, Matthias; Druz, Aliaksandr; Shridhar, Smriti; Chung, Cheng-Yu; Heffner, Kelley M.; Kreil, David P.; Betenbaugh, Mike; Shiloach, Joseph; Barron, Niall; Grillari, Johannes; Borth, Nicole

    2013-01-01

    microRNAs with their ability to regulate complex pathways that control cellular behavior and phenotype have been proposed as potential targets for cell engineering in the context of optimization of biopharmaceutical production cell lines, specifically of Chinese Hamster Ovary cells. However, until recently, research was limited by a lack of genomic sequence information on this industrially important cell line. With the publication of the genomic sequence and other relevant data sets for CHO cells since 2011, the doors have been opened for an improved understanding of CHO cell physiology and for the development of the necessary tools for novel engineering strategies. In the present review we discuss both knowledge on the regulatory mechanisms of microRNAs obtained from other biological models and proof of concepts already performed on CHO cells, thus providing an outlook of potential applications of microRNA engineering in production cell lines. PMID:23916872

  12. Dynamometer Testing of Planar Mixed-Potential Sensors

    DOE PAGES

    Kreller, C. R.; Sekhar, P. K.; Prikhodko, V.; ...

    2014-09-22

    Mixed-potential sensors for vehicle on-board emissions monitoring applications have been fabricated in an automotive planar sensor configuration using high temperature ceramic co-fire methods. The sensing element consists of dense Pt and LaSrCrO electrodes and a porous 3 mol% YSZ electrolyte. This sensor construct exhibits preferential selectivity to NO x (NO+NO 2) when operated at a positive current bias. The performance of the planar sensors under engine-out conditions was recently evaluated at the Oak Ridge National Laboratory National Transportation Research Center on a GM 1.9L CIDI diesel engine. The sensor response qualitatively tracked transients in NO x measured via FTIR undermore » transient engine operation. Additionally, quantitative correlation between sensor voltage response and total NO x concentration was obtained under steady-state engine speed and load while varying exhaust gas recirculation (EGR) levels.« less

  13. The potential role of telocytes in Tissue Engineering and Regenerative Medicine.

    PubMed

    Boos, Anja M; Weigand, Annika; Brodbeck, Rebekka; Beier, Justus P; Arkudas, Andreas; Horch, Raymund E

    2016-07-01

    Research and ideas for potential applications in the field of Tissue Engineering (TE) and Regenerative Medicine (RM) have been constantly increasing over recent years, basically driven by the fundamental human dream of repairing and regenerating lost tissue and organ functions. The basic idea of TE is to combine cells with putative stem cell properties with extracellular matrix components, growth factors and supporting matrices to achieve independently growing tissue. As a side effect, in the past years, more insights have been gained into cell-cell interaction and how to manipulate cell behavior. However, to date the ideal cell source has still to be found. Apart from commonly known various stem cell sources, telocytes (TC) have recently attracted increasing attention because they might play a potential role for TE and RM. It becomes increasingly evident that TC provide a regenerative potential and act in cellular communication through their network-forming telopodes. While TE in vitro experiments can be the first step, the key for elucidating their regenerative role will be the investigation of the interaction of TC with the surrounding tissue. For later clinical applications further steps have to include an upscaling process of vascularization of engineered tissue. Arteriovenous loop models to vascularize such constructs provide an ideal platform for preclinical testing of future therapeutic concepts in RM. The following review article should give an overview of what is known so far about the potential role of TC in TE and RM. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. 60NiTi Alloy for Tribological and Biomedical Surface Engineering Applications

    NASA Astrophysics Data System (ADS)

    Ingole, Sudeep

    2013-06-01

    60NiTi is an alloy with 60 wt% of nickel (Ni) and 40 wt% of titanium (Ti). This alloy was developed in the 1950s at the Naval Ordnance Laboratory (NOL) along with 55NiTi (55 wt% of Ni and 45 wt% of Ti). Both of these alloys exhibit the shape memory effect to different extents. The unique properties of 60NiTi, which are suitable for surface engineering (tribological) applications, are enumerated here. With appropriate heat treatment, this alloy can achieve high hardness (between Rc 55 and Rc 63). It has very good corrosion resistance and is resilient. Machinable before its final heat treatment, this alloy can be ground to fine surface finish and to tight dimensions. At one time, due to the popularity and wider applications of 55NiTi, the study of 60NiTi suffered. Recently, 60NiTi alloy gained some technological advantages due to advanced materials synthesis processes and progress in surface engineering. A feasibility study of 60NiTi bearings for space application has shown promise for its further development and suitability for other tribological applications. This report focuses on an overview of the properties and potential tribological and biomedical applications of 60NiTi.

  15. Camelina as a sustainable oilseed crop: contributions of plant breeding and genetic engineering.

    PubMed

    Vollmann, Johann; Eynck, Christina

    2015-04-01

    Camelina is an underutilized Brassicaceae oilseed plant with a considerable agronomic potential for biofuel and vegetable oil production in temperate regions. In contrast to most Brassicaceae, camelina is resistant to alternaria black spot and other diseases and pests. Sequencing of the camelina genome revealed an undifferentiated allohexaploid genome with a comparatively large number of genes and low percentage of repetitive DNA. As there is a close relationship between camelina and the genetic model plant Arabidopsis, this review aims at exploring the potential of translating basic Arabidopsis results into a camelina oilseed crop for food and non-food applications. Recently, Arabidopsis genes for drought resistance or increased photosynthesis and overall productivity have successfully been expressed in camelina. In addition, gene constructs affecting lipid metabolism pathways have been engineered into camelina for synthesizing either long-chain polyunsaturated fatty acids, hydroxy fatty acids or high-oleic oils in particular camelina strains, which is of great interest in human food, industrial or biofuel applications, respectively. These results confirm the potential of camelina to serve as a biotechnology platform in biorefinery applications thus justifying further investment in breeding and genetic research for combining agronomic potential, unique oil quality features and biosafety into an agricultural production system. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Development and Application of Microfabricated Chemical Gas Sensors For Aerospace Applications

    NASA Technical Reports Server (NTRS)

    Hunter, G. W.; Neudeck, P. G.; Fralick, G.; Thomas, V.; Liu, C. C.; Wu, Q. H.; Sawayda, M. S.; Jin, A.; Hammond, J.; Makel, D.; hide

    1990-01-01

    Aerospace applications require the development of chemical sensors with capabilities beyond those of commercially available sensors. In particular, factors such as minimal sensor size, weight, and power consumption are particularly important. Development areas which have potential aerospace applications include launch vehicle leak detection, engine health monitoring and control, and fire detection. Sensor development for these applications is based on progress in three types of technology: 1) Micromachining and microfabrication (Microsystem) technology to fabricate miniaturized sensors. 2) The use of nanocrystalline materials to develop sensors with improved stability combined with higher sensitivity. 3) The development of high temperature semiconductors, especially silicon carbide. Sensor development for each application involves its own challenges in the fields of materials science and fabrication technology. This paper discusses the needs of space applications and the point-contact sensor technology being developed to address these needs. Sensors to measure hydrogen, hydrocarbons, nitrogen oxides (Nox, carbon monoxide, oxygen, and carbon dioxide are being developed. A description is given of each sensor type and its present stage of development. Demonstration and application these sensor technologies will be described. The demonstrations range from use of a microsystem based hydrogen sensor on the Shuttle to engine demonstration of a nanocrystalline based sensor for NO, detection. It is concluded that microfabricated sensor technology has significant potential for use in a range of aerospace applications.

  17. Co-Optimization of Fuels & Engines: Fuel Blendstocks with the Potential to Optimize Future Gasoline Engine Performance; Identification of Five Chemical Families for Detailed Evaluation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Farrell, John T; Holladay, John; Wagner, Robert

    The U.S. Department of Energy's (DOE's) Co-Optimization of Fuels & Engines (Co-Optima) initiative is conducting the early-stage research needed to accelerate the market introduction of advanced fuel and engine technologies. The research includes both spark-ignition (SI) and compression-ignition (CI) combustion approaches, targeting applications that impact the entire on-road fleet (light-, medium-, and heavy-duty vehicles). The initiative's major goals include significant improvements in vehicle fuel economy, lower-cost pathways to reduce emissions, and leveraging diverse U.S. fuel resources. A key objective of Co-Optima's research is to identify new blendstocks that enhance current petroleum blending components, increase blendstock diversity, and provide refiners withmore » increased flexibility to blend fuels with the key properties required to optimize advanced internal combustion engines. This report identifies eight representative blendstocks from five chemical families that have demonstrated the potential to increase boosted SI engine efficiency, meet key fuel quality requirements, and be viable for production at commercial scale by 2025-2030.« less

  18. Nanomaterials for Craniofacial and Dental Tissue Engineering.

    PubMed

    Li, G; Zhou, T; Lin, S; Shi, S; Lin, Y

    2017-07-01

    Tissue engineering shows great potential as a future treatment for the craniofacial and dental defects caused by trauma, tumor, and other diseases. Due to the biomimetic features and excellent physiochemical properties, nanomaterials are of vital importance in promoting cell growth and stimulating tissue regeneration in tissue engineering. For craniofacial and dental tissue engineering, the frequently used nanomaterials include nanoparticles, nanofibers, nanotubes, and nanosheets. Nanofibers are attractive for cell invasion and proliferation because of their resemblance to extracellular matrix and the presence of large pores, and they have been used as scaffolds in bone, cartilage, and tooth regeneration. Nanotubes and nanoparticles improve the mechanical and chemical properties of scaffold, increase cell attachment and migration, and facilitate tissue regeneration. In addition, nanofibers and nanoparticles are also used as a delivery system to carry the bioactive agent in bone and tooth regeneration, have better control of the release speed of agent upon degradation of the matrix, and promote tissue regeneration. Although applications of nanomaterials in tissue engineering remain in their infancy with numerous challenges to face, the current results indicate that nanomaterials have massive potential in craniofacial and dental tissue engineering.

  19. Next generation bone tissue engineering: non-viral miR-133a inhibition using collagen-nanohydroxyapatite scaffolds rapidly enhances osteogenesis

    NASA Astrophysics Data System (ADS)

    Mencía Castaño, Irene; Curtin, Caroline M.; Duffy, Garry P.; O'Brien, Fergal J.

    2016-06-01

    Bone grafts are the second most transplanted materials worldwide at a global cost to healthcare systems valued over $30 billion every year. The influence of microRNAs in the regenerative capacity of stem cells offers vast therapeutic potential towards bone grafting; however their efficient delivery to the target site remains a major challenge. This study describes how the functionalisation of porous collagen-nanohydroxyapatite (nHA) scaffolds with miR-133a inhibiting complexes, delivered using non-viral nHA particles, enhanced human mesenchymal stem cell-mediated osteogenesis through the novel focus on a key activator of osteogenesis, Runx2. This study showed enhanced Runx2 and osteocalcin expression, as well as increased alkaline phosphatase activity and calcium deposition, thus demonstrating a further enhanced therapeutic potential of a biomaterial previously optimised for bone repair applications. The promising features of this platform offer potential for a myriad of applications beyond bone repair and tissue engineering, thus presenting a new paradigm for microRNA-based therapeutics.

  20. How Can Nanotechnology Help to Repair the Body? Advances in Cardiac, Skin, Bone, Cartilage and Nerve Tissue Regeneration

    PubMed Central

    Perán, Macarena; García, María Angel; Lopez-Ruiz, Elena; Jiménez, Gema; Marchal, Juan Antonio

    2013-01-01

    Nanotechnologists have become involved in regenerative medicine via creation of biomaterials and nanostructures with potential clinical implications. Their aim is to develop systems that can mimic, reinforce or even create in vivo tissue repair strategies. In fact, in the last decade, important advances in the field of tissue engineering, cell therapy and cell delivery have already been achieved. In this review, we will delve into the latest research advances and discuss whether cell and/or tissue repair devices are a possibility. Focusing on the application of nanotechnology in tissue engineering research, this review highlights recent advances in the application of nano-engineered scaffolds designed to replace or restore the followed tissues: (i) skin; (ii) cartilage; (iii) bone; (iv) nerve; and (v) cardiac. PMID:28809213

  1. [NEW PROGRESS OF ACELLULAR FISH SKIN AS NOVEL TISSUE ENGINEERED SCAFFOLD].

    PubMed

    Wei, Xiaojuan; Wang, Nanping; He, Lan; Guo, Xiuyu; Gu, Qisheng

    2016-11-08

    To review the recent research progress of acellular fish skin as a tissue engineered scaffold, and to analyze the feasibility and risk management in clinical application. The research and development, application status of acellular fish skin as a tissue engineered scaffold were comprehensively analyzed, and then several key points were put forward. Acellular fish skin has a huge potential in clinical practice as novel acellular extracellular matrix, but there have been no related research reports up to now in China. As an emerging point of translational medicine, investigation of acellular fish skin is mainly focused on artificial skin, surgical patch, and wound dressings. Development of acellular fish skin-based new products is concerned to be clinical feasible and necessary, but a lot of applied basic researches should be carried out.

  2. Study terrestrial applications of solar cell powered systems

    NASA Technical Reports Server (NTRS)

    Ravin, J. W.

    1973-01-01

    Terrestrial applications of solar cells and design systems are considered for those applications that show the most promise for becoming practical and accepted by users within the next five years. The study includes the definition, categorization, evaluation and screening of the most attractive potential terrestrial applications for solar cells. Potential markets are initially grouped and categorized in a general sense and are weighted in priority by their business volume, present and future. From a categorized list including marine, transportation, security, communication, meteorological and others, 66 potential solar cell applications have been cataloged. A methodology was formulated to include the criteria for evaluation and screening. The evaluation process covers all parts and components of the complete system required for each application and gives consideration to all factors, such as engineering, economic, production, marketing and other factors that may have an influence on the acceptance of the system.

  3. Emerging Roles for Extracellular Vesicles in Tissue Engineering and Regenerative Medicine

    PubMed Central

    Lamichhane, Tek N.; Sokic, Sonja; Schardt, John S.; Raiker, Rahul S.; Lin, Jennifer W.

    2015-01-01

    Extracellular vesicles (EVs)—comprising a heterogeneous population of cell-derived lipid vesicles including exosomes, microvesicles, and others—have recently emerged as both mediators of intercellular information transfer in numerous biological systems and vehicles for drug delivery. In both roles, EVs have immense potential to impact tissue engineering and regenerative medicine applications. For example, the therapeutic effects of several progenitor and stem cell-based therapies have been attributed primarily to EVs secreted by these cells, and EVs have been recently reported to play direct roles in injury-induced tissue regeneration processes in multiple physiological systems. In addition, EVs have been utilized for targeted drug delivery in regenerative applications and possess unique potential to be harnessed as patient-derived drug delivery vehicles for personalized medicine. This review discusses EVs in the context of tissue repair and regeneration, including their utilization as drug carriers and their crucial role in cell-based therapies. Furthermore, the article highlights the growing need for bioengineers to understand, consider, and ultimately design and specifically control the activity of EVs to maximize the efficacy of tissue engineering and regenerative therapies. PMID:24957510

  4. Engineering stem cells for future medicine.

    PubMed

    Ricotti, Leonardo; Menciassi, Arianna

    2013-03-01

    Despite their great potential in regenerative medicine applications, stem cells (especially pluripotent ones) currently show a limited clinical success, partly due to a lack of biological knowledge, but also due to a lack of specific and advanced technological instruments able to overcome the current boundaries of stem cell functional maturation and safe/effective therapeutic delivery. This paper aims at describing recent insights, current limitations, and future horizons related to therapeutic stem cells, by analyzing the potential of different bioengineering disciplines in bringing stem cells toward a safe clinical use. First, we clarify how and why stem cells should be properly engineered and which could be in a near future the challenges and the benefits connected with this process. Second, we identify different routes toward stem cell differentiation and functional maturation, relying on chemical, mechanical, topographical, and direct/indirect physical stimulation. Third, we highlight how multiscale modeling could strongly support and optimize stem cell engineering. Finally, we focus on future robotic tools that could provide an added value to the extent of translating basic biological knowledge into clinical applications, by developing ad hoc enabling technologies for stem cell delivery and control.

  5. LOW-ENGINE-FRICTION TECHNOLOGY FOR ADVANCED NATURAL-GAS RECIPROCATING ENGINES

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Victor Wong; Tian Tian; Luke Moughon

    This program aims at improving the efficiency of advanced natural-gas reciprocating engines (ANGRE) by reducing piston and piston ring assembly friction without major adverse effects on engine performance, such as increased oil consumption and wear. An iterative process of simulation, experimentation and analysis is being followed towards achieving the goal of demonstrating a complete optimized low-friction engine system. To date, a detailed set of piston and piston-ring dynamic and friction models have been developed and applied that illustrate the fundamental relationships among mechanical, surface/material and lubricant design parameters and friction losses. Demonstration of low-friction ring-pack designs in the Waukesha VGFmore » 18GL engine confirmed total engine FEMP (friction mean effective pressure) reduction of 7-10% from the baseline configuration without significantly increasing oil consumption or blow-by flow. This represents a substantial (30-40%) reduction of the ringpack friction alone. The measured FMEP reductions were in good agreement with the model predictions. Further improvements via piston, lubricant, and surface designs offer additional opportunities. Tests of low-friction lubricants are in progress and preliminary results are very promising. The combined analysis of lubricant and surface design indicates that low-viscosity lubricants can be very effective in reducing friction, subject to component wear for extremely thin oils, which can be mitigated with further lubricant formulation and/or engineered surfaces. Hence a combined approach of lubricant design and appropriate wear reduction offers improved potential for minimum engine friction loss. Piston friction studies indicate that a flatter piston with a more flexible skirt, together with optimizing the waviness and film thickness on the piston skirt offer significant friction reduction. Combined with low-friction ring-pack, material and lubricant parameters, a total power cylinder friction reduction of 30-50% is expected, translating to an engine efficiency increase of two percentage points from its current baseline towards the goal of 50% ARES engine efficiency. The design strategies developed in this study have promising potential for application in all modern reciprocating engines as they represent simple, low-cost methods to extract significant fuel savings. The current program has possible spinoffs and applications in other industries as well, including transportation, CHP, and diesel power generation. The progress made in this program has wide engine efficiency implications, and potential deployment of low-friction engine components or lubricants in the near term is possible as current investigations continue.« less

  6. Synthesis and optimization of chitosan nanoparticles: Potential applications in nanomedicine and biomedical engineering.

    PubMed

    Ghadi, Arezou; Mahjoub, Soleiman; Tabandeh, Fatemeh; Talebnia, Farid

    2014-01-01

    Chitosan nanoparticles have become of great interest for nanomedicine, biomedical engineering and development of new therapeutic drug release systems with improved bioavailability, increased specificity and sensitivity, and reduced pharmacological toxicity. The aim of the present study was to synthesis and optimize of the chitosan nanoparticles for industrial and biomedical applications. Fe3O4 was synthesized and optimized as magnetic core nanoparticles and then chitosan covered this magnetic core. The size and morphology of the nano-magnetic chitosan was analyzed by scanning electron microscope (SEM). Topography and size distribution of the nanoparticles were shown with two-dimensional and three-dimensional images of atomic force microscopy (AFM). The nanoparticles were analyzed using transmission electron microscopy (TEM). The chitosan nanoparticles prepared in the experiment exhibited white powder shape. The SEM micrographs of the nano-magnetic chitosan showed that they were approximately uniform spheres. The unmodified chitosan nanoparticles composed of clusters of nanoparticles with sizes ranging from 10 nm to 80 nm. AFM provides a three-dimensional surface profile. The TEM image showed physical aggregation of the chitosan nanoparticles. The results show that a novel chitosan nanoparticle was successfully synthesized and characterized. It seems that this nanoparticle like the other chitosan nano particles has potential applications for nanomedicine, biomedical engineering, industrial and pharmaceutical fields.

  7. Erythrocytes-based synthetic delivery systems: transition from conventional to novel engineering strategies.

    PubMed

    Bhateria, Manisha; Rachumallu, Ramakrishna; Singh, Rajbir; Bhatta, Rabi Sankar

    2014-08-01

    Erythrocytes (red blood cells [RBCs]) and artificial or synthetic delivery systems such as liposomes, nanoparticles (NPs) are the most investigated carrier systems. Herein, progress made from conventional approach of using RBC as delivery systems to novel approach of using synthetic delivery systems based on RBC properties will be reviewed. We aim to highlight both conventional and novel approaches of using RBCs as potential carrier system. Conventional approaches which include two main strategies are: i) directly loading therapeutic moieties in RBCs; and ii) coupling them with RBCs whereas novel approaches exploit structural, mechanical and biological properties of RBCs to design synthetic delivery systems through various engineering strategies. Initial attempts included coupling of antibodies to liposomes to specifically target RBCs. Knowledge obtained from several studies led to the development of RBC membrane derived liposomes (nanoerythrosomes), inspiring future application of RBC or its structural features in other attractive delivery systems (hydrogels, filomicelles, microcapsules, micro- and NPs) for even greater potential. In conclusion, this review dwells upon comparative analysis of various conventional and novel engineering strategies in developing RBC based drug delivery systems, diversifying their applications in arena of drug delivery. Regardless of the challenges in front of us, RBC based delivery systems offer an exciting approach of exploiting biological entities in a multitude of medical applications.

  8. Chemical Reactive Anchoring Lipids with Different Performance for Cell Surface Re-engineering Application.

    PubMed

    Vabbilisetty, Pratima; Boron, Mallorie; Nie, Huan; Ozhegov, Evgeny; Sun, Xue-Long

    2018-02-28

    Introduction of selectively chemical reactive groups at the cell surface enables site-specific cell surface labeling and modification opportunity, thus facilitating the capability to study the cell surface molecular structure and function and the molecular mechanism it underlies. Further, it offers the opportunity to change or improve a cell's functionality for interest of choice. In this study, two chemical reactive anchor lipids, phosphatidylethanolamine-poly(ethylene glycol)-dibenzocyclooctyne (DSPE-PEG 2000 -DBCO) and cholesterol-PEG-dibenzocyclooctyne (CHOL-PEG 2000 -DBCO) were synthesized and their potential application for cell surface re-engineering via lipid fusion were assessed with RAW 264.7 cells as a model cell. Briefly, RAW 264.7 cells were incubated with anchor lipids under various concentrations and at different incubation times. The successful incorporation of the chemical reactive anchor lipids was confirmed by biotinylation via copper-free click chemistry, followed by streptavidin-fluorescein isothiocyanate binding. In comparison, the cholesterol-based anchor lipid afforded a higher cell membrane incorporation efficiency with less internalization than the phospholipid-based anchor lipid. Low cytotoxicity of both anchor lipids upon incorporation into the RAW 264.7 cells was observed. Further, the cell membrane residence time of the cholesterol-based anchor lipid was evaluated with confocal microscopy. This study suggests the potential cell surface re-engineering applications of the chemical reactive anchor lipids.

  9. Biocatalysis in the Pharmaceutical Industry: The Need for Speed

    PubMed Central

    2017-01-01

    The use of biocatalysis in the pharmaceutical industry continues to expand as a result of increased access to enzymes and the ability to engineer those enzymes to meet the demands of industrial processes. However, we are still just scratching the surface of potential biocatalytic applications. The time pressures present in pharmaceutical process development are incompatible with the long lead times required for engineering a suitable biocatalyst. Dramatic increases in the speed of protein engineering are needed to deliver on the ever increasing opportunities for industrial biocatalytic processes. PMID:28523096

  10. Biocatalysis in the Pharmaceutical Industry: The Need for Speed.

    PubMed

    Truppo, Matthew D

    2017-05-11

    The use of biocatalysis in the pharmaceutical industry continues to expand as a result of increased access to enzymes and the ability to engineer those enzymes to meet the demands of industrial processes. However, we are still just scratching the surface of potential biocatalytic applications. The time pressures present in pharmaceutical process development are incompatible with the long lead times required for engineering a suitable biocatalyst. Dramatic increases in the speed of protein engineering are needed to deliver on the ever increasing opportunities for industrial biocatalytic processes.

  11. Platelet-Rich Blood Derivatives for Stem Cell-Based Tissue Engineering and Regeneration

    PubMed Central

    Kaushik, Gaurav; Leijten, Jeroen; Khademhosseini, Ali

    2016-01-01

    Platelet rich blood derivatives have been widely used in different fields of medicine and stem cell based tissue engineering. They represent natural cocktails of autologous growth factor, which could provide an alternative for recombinant protein based approaches. Platelet rich blood derivatives, such as platelet rich plasma, have consistently shown to potentiate stem cell proliferation, migration, and differentiation. Here, we review the spectrum of platelet rich blood derivatives, discuss their current applications in tissue engineering and regenerative medicine, reflect on their effect on stem cells, and highlight current translational challenges. PMID:27047733

  12. Synthetic biology approaches to engineer T cells.

    PubMed

    Wu, Chia-Yung; Rupp, Levi J; Roybal, Kole T; Lim, Wendell A

    2015-08-01

    There is rapidly growing interest in learning how to engineer immune cells, such as T lymphocytes, because of the potential of these engineered cells to be used for therapeutic applications such as the recognition and killing of cancer cells. At the same time, our knowhow and capability to logically engineer cellular behavior is growing rapidly with the development of synthetic biology. Here we describe how synthetic biology approaches are being used to rationally alter the behavior of T cells to optimize them for therapeutic functions. We also describe future developments that will be important in order to construct safe and precise T cell therapeutics. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. The Role of Bioreactors in Ligament and Tendon Tissue Engineering.

    PubMed

    Mace, James; Wheelton, Andy; Khan, Wasim S; Anand, Sanj

    2016-01-01

    Bioreactors are pivotal to the emerging field of tissue engineering. The formation of neotissue from pluripotent cell lineages potentially offers a source of tissue for clinical use without the significant donor site morbidity associated with many contemporary surgical reconstructive procedures. Modern bioreactor design is becoming increasingly complex to provide a both an expandable source of readily available pluripotent cells and to facilitate their controlled differentiation into a clinically applicable ligament or tendon like neotissue. This review presents the need for such a method, challenges in the processes to engineer neotissue and the current designs and results of modern bioreactors in the pursuit of engineered tendon and ligament.

  14. Tissue engineering in dentistry.

    PubMed

    Abou Neel, Ensanya Ali; Chrzanowski, Wojciech; Salih, Vehid M; Kim, Hae-Won; Knowles, Jonathan C

    2014-08-01

    of this review is to inform practitioners with the most updated information on tissue engineering and its potential applications in dentistry. The authors used "PUBMED" to find relevant literature written in English and published from the beginning of tissue engineering until today. A combination of keywords was used as the search terms e.g., "tissue engineering", "approaches", "strategies" "dentistry", "dental stem cells", "dentino-pulp complex", "guided tissue regeneration", "whole tooth", "TMJ", "condyle", "salivary glands", and "oral mucosa". Abstracts and full text articles were used to identify causes of craniofacial tissue loss, different approaches for craniofacial reconstructions, how the tissue engineering emerges, different strategies of tissue engineering, biomaterials employed for this purpose, the major attempts to engineer different dental structures, finally challenges and future of tissue engineering in dentistry. Only those articles that dealt with the tissue engineering in dentistry were selected. There have been a recent surge in guided tissue engineering methods to manage periodontal diseases beyond the traditional approaches. However, the predictable reconstruction of the innate organisation and function of whole teeth as well as their periodontal structures remains challenging. Despite some limited progress and minor successes, there remain distinct and important challenges in the development of reproducible and clinically safe approaches for oral tissue repair and regeneration. Clearly, there is a convincing body of evidence which confirms the need for this type of treatment, and public health data worldwide indicates a more than adequate patient resource. The future of these therapies involving more biological approaches and the use of dental tissue stem cells is promising and advancing. Also there may be a significant interest of their application and wider potential to treat disorders beyond the craniofacial region. Considering the interests of the patients who could possibly be helped by applying stem cell-based therapies should be carefully assessed against current ethical concerns regarding the moral status of the early embryo. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Manufacture and Drug Delivery Applications of Silk Nanoparticles.

    PubMed

    Wongpinyochit, Thidarat; Johnston, Blair F; Seib, F Philipp

    2016-10-08

    Silk is a promising biopolymer for biomedical and pharmaceutical applications due to its outstanding mechanical properties, biocompatibility and biodegradability, as well its ability to protect and subsequently release its payload in response to a trigger. While silk can be formulated into various material formats, silk nanoparticles are emerging as promising drug delivery systems. Therefore, this article covers the procedures for reverse engineering silk cocoons to yield a regenerated silk solution that can be used to generate stable silk nanoparticles. These nanoparticles are subsequently characterized, drug loaded and explored as a potential anticancer drug delivery system. Briefly, silk cocoons are reverse engineered first by degumming the cocoons, followed by silk dissolution and clean up, to yield an aqueous silk solution. Next, the regenerated silk solution is subjected to nanoprecipitation to yield silk nanoparticles - a simple but powerful method that generates uniform nanoparticles. The silk nanoparticles are characterized according to their size, zeta potential, morphology and stability in aqueous media, as well as their ability to entrap a chemotherapeutic payload and kill human breast cancer cells. Overall, the described methodology yields uniform silk nanoparticles that can be readily explored for a myriad of applications, including their use as a potential nanomedicine.

  16. Step-wise potential development across the lipid bilayer under external electric fields

    NASA Astrophysics Data System (ADS)

    Majhi, Amit Kumar

    2018-04-01

    Pore formation across the bilayers under external electric field is an important phenomenon, which has numerous applications in biology and bio-engineering fields. However, it is not a ubiquitous event under all field applications. To initiate a pore in the bilayer a particular threshold electric field is required. The electric field alters the intrinsic potential distribution across the bilayer as we as it enhances total potential drop across the bilayer, which causes the pore formation. The intrinsic potential profile has a maximum peak value, which is 0.8 V and it gets enhanced under application of external field, 0.43 V/nm. The peak value becomes 1.4 V when a pore appears in the bilayer and it continues to evolve as along as the external electric field remains switched on.

  17. Chemical Vapor Deposition Of Silicon Carbide

    NASA Technical Reports Server (NTRS)

    Powell, J. Anthony; Larkin, David J.; Matus, Lawrence G.; Petit, Jeremy B.

    1993-01-01

    Large single-crystal SiC boules from which wafers of large area cut now being produced commerically. Availability of wafers opens door for development of SiC semiconductor devices. Recently developed chemical vapor deposition (CVD) process produces thin single-crystal SiC films on SiC wafers. Essential step in sequence of steps used to fabricate semiconductor devices. Further development required for specific devices. Some potential high-temperature applications include sensors and control electronics for advanced turbine engines and automobile engines, power electronics for electromechanical actuators for advanced aircraft and for space power systems, and equipment used in drilling of deep wells. High-frequency applications include communication systems, high-speed computers, and microwave power transistors. High-radiation applications include sensors and controls for nuclear reactors.

  18. Advanced supersonic propulsion study. [with emphasis on noise level reduction

    NASA Technical Reports Server (NTRS)

    Sabatella, J. A. (Editor)

    1974-01-01

    A study was conducted to determine the promising propulsion systems for advanced supersonic transport application, and to identify the critical propulsion technology requirements. It is shown that noise constraints have a major effect on the selection of the various engine types and cycle parameters. Several promising advanced propulsion systems were identified which show the potential of achieving lower levels of sideline jet noise than the first generation supersonic transport systems. The non-afterburning turbojet engine, utilizing a very high level of jet suppression, shows the potential to achieve FAR 36 noise level. The duct-heating turbofan with a low level of jet suppression is the most attractive engine for noise levels from FAR 36 to FAR 36 minus 5 EPNdb, and some series/parallel variable cycle engines show the potential of achieving noise levels down to FAR 36 minus 10 EPNdb with moderate additional penalty. The study also shows that an advanced supersonic commercial transport would benefit appreciably from advanced propulsion technology. The critical propulsion technology needed for a viable supersonic propulsion system, and the required specific propulsion technology programs are outlined.

  19. Mid-Infrared Laser Absorption Diagnostics for Combustion and Propulsion Applications

    DTIC Science & Technology

    2010-12-01

    Combustion and Propulsion Applications 5a. CONTRACT NUMBER 5b. GRANT NUMBER N00014-07-1-0844 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Matthew A...Institute Mechancial, Aerospace, and Nuclear Engineering Dept Troy NY 12180-3590 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING / MONITORING...absorption sensors based on quantum cascade laser (QCL) technology for combustion and propulsion applications. To demonstrate the potential of mid-IR QCL

  20. Powder-driven-nail connections for round timber

    Treesearch

    Ronald W. Wolfe; KugBo Shim; Marshall Begel

    2003-01-01

    In an effort to encourage the development of value-added engineered applications for small diameter round timber, research is being conducted at the US Forest Products Laboratory to develop and verify design guidelines for connections with specific application to round timbers. The objective of this work is to provide potential users with a number of viable connection...

  1. Tissue engineering for clinical applications.

    PubMed

    Bhatia, Sujata K

    2010-12-01

    Tissue engineering is increasingly being recognized as a beneficial means for lessening the global disease burden. One strategy of tissue engineering is to replace lost tissues or organs with polymeric scaffolds that contain specialized populations of living cells, with the goal of regenerating tissues to restore normal function. Typical constructs for tissue engineering employ biocompatible and degradable polymers, along with organ-specific and tissue-specific cells. Once implanted, the construct guides the growth and development of new tissues; the polymer scaffold degrades away to be replaced by healthy functioning tissue. The ideal biomaterial for tissue engineering not only defends against disease and supports weakened tissues or organs, it also provides the elements required for healing and repair, stimulates the body's intrinsic immunological and regenerative capacities, and seamlessly interacts with the living body. Tissue engineering has been investigated for virtually every organ system in the human body. This review describes the potential of tissue engineering to alleviate disease, as well as the latest advances in tissue regeneration. The discussion focuses on three specific clinical applications of tissue engineering: cardiac tissue regeneration for treatment of heart failure; nerve regeneration for treatment of stroke; and lung regeneration for treatment of chronic obstructive pulmonary disease. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Tissue Regeneration: A Silk Road.

    PubMed

    Jao, Dave; Mou, Xiaoyang; Hu, Xiao

    2016-08-05

    Silk proteins are natural biopolymers that have extensive structural possibilities for chemical and mechanical modifications to facilitate novel properties, functions, and applications in the biomedical field. The versatile processability of silk fibroins (SF) into different forms such as gels, films, foams, membranes, scaffolds, and nanofibers makes it appealing in a variety of applications that require mechanically superior, biocompatible, biodegradable, and functionalizable biomaterials. There is no doubt that nature is the world's best biological engineer, with simple, exquisite but powerful designs that have inspired novel technologies. By understanding the surface interaction of silk materials with living cells, unique characteristics can be implemented through structural modifications, such as controllable wettability, high-strength adhesiveness, and reflectivity properties, suggesting its potential suitability for surgical, optical, and other biomedical applications. All of the interesting features of SF, such as tunable biodegradation, anti-bacterial properties, and mechanical properties combined with potential self-healing modifications, make it ideal for future tissue engineering applications. In this review, we first demonstrate the current understanding of the structures and mechanical properties of SF and the various functionalizations of SF matrices through chemical and physical manipulations. Then the diverse applications of SF architectures and scaffolds for different regenerative medicine will be discussed in detail, including their current applications in bone, eye, nerve, skin, tendon, ligament, and cartilage regeneration.

  3. Performance Benefits for a Turboshaft Engine Using Nonlinear Engine Control Technology Investigated

    NASA Technical Reports Server (NTRS)

    Jones, Scott M.

    2004-01-01

    The potential benefits of nonlinear engine control technology applied to a General Electric T700 helicopter engine were investigated. This technology is being developed by the U.S. Navy SPAWAR Systems Center for a variety of applications. When used as a means of active stability control, nonlinear engine control technology uses sensors and small amounts of injected air to allow compressors to operate with reduced stall margin, which can improve engine pressure ratio. The focus of this study was to determine the best achievable reduction in fuel consumption for the T700 turboshaft engine. A customer deck (computer code) was provided by General Electric to calculate the T700 engine performance, and the NASA Glenn Research Center used this code to perform the analysis. The results showed a 2- to 5-percent reduction in brake specific fuel consumption (BSFC) at the three Sikorsky H-60 helicopter operating points of cruise, loiter, and hover.

  4. Gene delivery in tissue engineering and regenerative medicine.

    PubMed

    Fang, Y L; Chen, X G; W T, Godbey

    2015-11-01

    As a promising strategy to aid or replace tissue/organ transplantation, gene delivery has been used for regenerative medicine applications to create or restore normal function at the cell and tissue levels. Gene delivery has been successfully performed ex vivo and in vivo in these applications. Excellent proliferation capabilities and differentiation potentials render certain cells as excellent candidates for ex vivo gene delivery for regenerative medicine applications, which is why multipotent and pluripotent cells have been intensely studied in this vein. In this review, gene delivery is discussed in detail, along with its applications to tissue engineering and regenerative medicine. A definition of a stem cell is compared to a definition of a stem property, and both provide the foundation for an in-depth look at gene delivery investigations from a germ lineage angle. © 2014 Wiley Periodicals, Inc.

  5. Solar powered Stirling cycle electrical generator

    NASA Technical Reports Server (NTRS)

    Shaltens, Richard K.

    1991-01-01

    Under NASA's Civil Space Technology Initiative (CSTI), the NASA Lewis Research Center is developing the technology needed for free-piston Stirling engines as a candidate power source for space systems in the late 1990's and into the next century. Space power requirements include high efficiency, very long life, high reliability, and low vibration. Furthermore, system weight and operating temperature are important. The free-piston Stirling engine has the potential for a highly reliable engine with long life because it has only a few moving parts, non-contacting gas bearings, and can be hermetically sealed. These attributes of the free-piston Stirling engine also make it a viable candidate for terrestrial applications. In cooperation with the Department of Energy, system designs are currently being completed that feature the free-piston Stirling engine for terrestrial applications. Industry teams were assembled and are currently completing designs for two Advanced Stirling Conversion Systems utilizing technology being developed under the NASA CSTI Program. These systems, when coupled with a parabolic mirror to collect the solar energy, are capable of producing about 25 kW of electricity to a utility grid. Industry has identified a niche market for dish Stirling systems for worldwide remote power application. They believe that these niche markets may play a major role in the introduction of Stirling products into the commercial market.

  6. Engineering management of large scale systems

    NASA Technical Reports Server (NTRS)

    Sanders, Serita; Gill, Tepper L.; Paul, Arthur S.

    1989-01-01

    The organization of high technology and engineering problem solving, has given rise to an emerging concept. Reasoning principles for integrating traditional engineering problem solving with system theory, management sciences, behavioral decision theory, and planning and design approaches can be incorporated into a methodological approach to solving problems with a long range perspective. Long range planning has a great potential to improve productivity by using a systematic and organized approach. Thus, efficiency and cost effectiveness are the driving forces in promoting the organization of engineering problems. Aspects of systems engineering that provide an understanding of management of large scale systems are broadly covered here. Due to the focus and application of research, other significant factors (e.g., human behavior, decision making, etc.) are not emphasized but are considered.

  7. Perspectives on biotechnological applications of archaea

    PubMed Central

    Schiraldi, Chiara; Giuliano, Mariateresa; De Rosa, Mario

    2002-01-01

    Many archaea colonize extreme environments. They include hyperthermophiles, sulfur-metabolizing thermophiles, extreme halophiles and methanogens. Because extremophilic microorganisms have unusual properties, they are a potentially valuable resource in the development of novel biotechnological processes. Despite extensive research, however, there are few existing industrial applications of either archaeal biomass or archaeal enzymes. This review summarizes current knowledge about the biotechnological uses of archaea and archaeal enzymes with special attention to potential applications that are the subject of current experimental evaluation. Topics covered include cultivation methods, recent achievements in genomics, which are of key importance for the development of new biotechnological tools, and the application of wild-type biomasses, engineered microorganisms, enzymes and specific metabolites in particular bioprocesses of industrial interest. PMID:15803645

  8. Perspectives on biotechnological applications of archaea.

    PubMed

    Schiraldi, Chiara; Giuliano, Mariateresa; De Rosa, Mario

    2002-09-01

    Many archaea colonize extreme environments. They include hyperthermophiles, sulfur-metabolizing thermophiles, extreme halophiles and methanogens. Because extremophilic microorganisms have unusual properties, they are a potentially valuable resource in the development of novel biotechnological processes. Despite extensive research, however, there are few existing industrial applications of either archaeal biomass or archaeal enzymes. This review summarizes current knowledge about the biotechnological uses of archaea and archaeal enzymes with special attention to potential applications that are the subject of current experimental evaluation. Topics covered include cultivation methods, recent achievements in genomics, which are of key importance for the development of new biotechnological tools, and the application of wild-type biomasses, engineered microorganisms, enzymes and specific metabolites in particular bioprocesses of industrial interest.

  9. Tailored Carbon Nanotubes for Tissue Engineering Applications

    PubMed Central

    Veetil, Jithesh V.; Ye, Kaiming

    2008-01-01

    A decade of aggressive researches on carbon nanotubes (CNTs) has paved way for extending these unique nanomaterials into a wide range of applications. In the relatively new arena of nanobiotechnology, a vast majority of applications are based on CNTs, ranging from miniaturized biosensors to organ regeneration. Nevertheless, the complexity of biological systems poses a significant challenge in developing CNT-based tissue engineering applications. This review focuses on the recent developments of CNT-based tissue engineering, where the interaction between living cells/tissues and the nanotubes have been transformed into a variety of novel techniques. This integration has already resulted in a revaluation of tissue engineering and organ regeneration techniques. Some of the new treatments that were not possible previously become reachable now. Because of the advent of surface chemistry, the CNT’s biocompatibility has been significantly improved, making it possible to serve as tissue scaffolding materials to enhance the organ regeneration. The superior mechanic strength and chemical inert also makes it ideal for blood compatible applications, especially for cardiopulmonary bypass surgery. The applications of CNTs in these cardiovascular surgeries led to a remarkable improvement in mechanical strength of implanted catheters and reduced thrombogenecity after surgery. Moreover, the functionalized CNTs have been extensively explored for in vivo targeted drug or gene delivery, which could potentially improve the efficiency of many cancer treatments. However, just like other nanomaterials, the cytotoxicity of CNTs has not been well established. Hence, more extensive cytotoxic studies are warranted while converting the hydrophobic CNTs into biocompatible nanomaterials. PMID:19496152

  10. Fractal and spectroscopic analysis of soot from internal combustion engines

    NASA Astrophysics Data System (ADS)

    Swapna, M. S.; Saritha Devi, H. V.; Raj, Vimal; Sankararaman, S.

    2018-03-01

    Today diesel engines are used worldwide for various applications and very importantly in transportation. Hydrocarbons are the most widespread precursors among carbon sources employed in the production of carbon nanotubes (CNTs). The aging of internal combustion engine is an important parameter in deciding the carbon emission and particulate matter due to incomplete combustion of fuel. In the present work, an attempt has been made for the effective utilization of the aged engines for potential applicationapplications in fuel cells and nanoelectronics. To analyze the impact of aging, the particulate matter rich in carbon content areis collected from diesel engines of different ages. The soot with CNTs is purified by the liquid phase oxidation method and analyzed by Field Emission Scanning Electron Microscopy, High-Resolution Transmission Electron Microscopy, Energy Dispersive Spectroscopy, UV-Visible spectroscopy, Raman spectroscopy and Thermogravimetric analysis. The SEM image contains self-similar patterns probing fractal analysis. The fractal dimensions of the samples are determined by the box counting method. We could find a greater amount of single-walled carbon nanotubes (SWCNTs) in the particulate matter emitted by aged diesel engines and thereby giving information about the combustion efficiency of the engine. The SWCNT rich sample finds a wide range of applicationapplications in nanoelectronics and thereby pointing a potential use of these aged engines.

  11. Recent advances in synthetic biosafety

    PubMed Central

    Simon, Anna J.; Ellington, Andrew D.

    2016-01-01

    Synthetically engineered organisms hold promise for a broad range of medical, environmental, and industrial applications. Organisms can potentially be designed, for example, for the inexpensive and environmentally benign synthesis of pharmaceuticals and industrial chemicals, for the cleanup of environmental pollutants, and potentially even for biomedical applications such as the targeting of specific diseases or tissues. However, the use of synthetically engineered organisms comes with several reasonable safety concerns, one of which is that the organisms or their genes could escape their intended habitats and cause environmental disruption. Here we review key recent developments in this emerging field of synthetic biocontainment and discuss further developments that might be necessary for the widespread use of synthetic organisms. Specifically, we discuss the history and modern development of three strategies for the containment of synthetic microbes: addiction to an exogenously supplied ligand; self-killing outside of a designated environment; and self-destroying encoded DNA circuitry outside of a designated environment. PMID:27635235

  12. Applications of Endothermic Reaction Technology to the High Speed Civil Transport

    NASA Technical Reports Server (NTRS)

    Glickstein, Marvin R.; Spadaccini, Louis J.

    1998-01-01

    The success of strategies for controlling emissions and enhancing performance in High Speed Research applications may be Increased by more effective utilization of the heat sink afforded by the fuel in the vehicle thermal management system. This study quantifies the potential benefits associated with the use of supercritical preheating and endothermic cracking of let fuel prior to combustion to enhance the thermal management capabilities of the propulsion systems in the High Speed Civil Transport (HSCT). A fuel-cooled thermal management system, consisting of plate-fin heat exchangers and a small auxiliary compressor, is defined for the HSCT, Integrated with the engine, and an assessment of the effect on engine performance, weight, and operating cost is performed. The analysis indicates significant savings due a projected improvement in fuel economy, and the potential for additional benefit if the cycle is modified to take full advantage of all the heat sink available in the fuel.

  13. Creating biological nanomaterials using synthetic biology.

    PubMed

    Rice, MaryJoe K; Ruder, Warren C

    2014-02-01

    Synthetic biology is a new discipline that combines science and engineering approaches to precisely control biological networks. These signaling networks are especially important in fields such as biomedicine and biochemical engineering. Additionally, biological networks can also be critical to the production of naturally occurring biological nanomaterials, and as a result, synthetic biology holds tremendous potential in creating new materials. This review introduces the field of synthetic biology, discusses how biological systems naturally produce materials, and then presents examples and strategies for incorporating synthetic biology approaches in the development of new materials. In particular, strategies for using synthetic biology to produce both organic and inorganic nanomaterials are discussed. Ultimately, synthetic biology holds the potential to dramatically impact biological materials science with significant potential applications in medical systems.

  14. Oxygen-hydrogen thrusters for Space Station auxiliary propulsion systems

    NASA Technical Reports Server (NTRS)

    Berkman, D. K.

    1984-01-01

    The feasibility and technology requirements of a low-thrust, high-performance, long-life, gaseous oxygen (GO2)/gaseous hydrogen (GH2) thruster were examined. Candidate engine concepts for auxiliary propulsion systems for space station applications were identified. The low-thrust engine (5 to 100 lb sub f) requires significant departure from current applications of oxygen/hydrogen propulsion technology. Selection of the thrust chamber material and cooling method needed or long life poses a major challenge. The use of a chamber material requiring a minimum amount of cooling or the incorporation of regenerative cooling were the only choices available with the potential of achieving very high performance. The design selection for the injector/igniter, the design and fabrication of a regeneratively cooled copper chamber, and the design of a high-temperature rhenium chamber were documented and the performance and heat transfer results obtained from the test program conducted at JPL using the above engine components presented. Approximately 115 engine firings were conducted in the JPL vacuum test facility, using 100:1 expansion ratio nozzles. Engine mixture ratio and fuel-film cooling percentages were parametrically investigated for each test configuration.

  15. The case for applying tissue engineering methodologies to instruct human organoid morphogenesis.

    PubMed

    Marti-Figueroa, Carlos R; Ashton, Randolph S

    2017-05-01

    Three-dimensional organoids derived from human pluripotent stem cell (hPSC) derivatives have become widely used in vitro models for studying development and disease. Their ability to recapitulate facets of normal human development during in vitro morphogenesis produces tissue structures with unprecedented biomimicry. Current organoid derivation protocols primarily rely on spontaneous morphogenesis processes to occur within 3-D spherical cell aggregates with minimal to no exogenous control. This yields organoids containing microscale regions of biomimetic tissues, but at the macroscale (i.e. 100's of microns to millimeters), the organoids' morphology, cytoarchitecture, and cellular composition are non-biomimetic and variable. The current lack of control over in vitro organoid morphogenesis at the microscale induces aberrations at the macroscale, which impedes realization of the technology's potential to reproducibly form anatomically correct human tissue units that could serve as optimal human in vitro models and even transplants. Here, we review tissue engineering methodologies that could be used to develop powerful approaches for instructing multiscale, 3-D human organoid morphogenesis. Such technological mergers are critically needed to harness organoid morphogenesis as a tool for engineering functional human tissues with biomimetic anatomy and physiology. Human PSC-derived 3-D organoids are revolutionizing the biomedical sciences. They enable the study of development and disease within patient-specific genetic backgrounds and unprecedented biomimetic tissue microenvironments. However, their uncontrolled, spontaneous morphogenesis at the microscale yields inconsistences in macroscale organoid morphology, cytoarchitecture, and cellular composition that limits their standardization and application. Integration of tissue engineering methods with organoid derivation protocols could allow us to harness their potential by instructing standardized in vitro morphogenesis to generate organoids with biomimicry at all scales. Such advancements would enable the use of organoids as a basis for 'next-generation' tissue engineering of functional, anatomically mimetic human tissues and potentially novel organ transplants. Here, we discuss critical aspects of organoid morphogenesis where application of innovative tissue engineering methodologies would yield significant advancement towards this goal. Copyright © 2017. Published by Elsevier Ltd.

  16. A suite of engineered GFP molecules for oligomeric scaffolding

    DOE PAGES

    Leibly, David J.; Arbing, Mark A.; Pashkov, Inna; ...

    2015-08-13

    Applications ranging from synthetic biology to protein crystallization could be advanced by facile systems for connecting multiple proteins together in predefined spatial relationships. One approach to this goal is to engineer many distinct assembly forms of a single carrier protein or scaffold, to which other proteins of interest can then be readily attached. In this work we chose GFP as a scaffold and engineered many alternative oligomeric forms, driven by either specific disulfide bond formation or metal ion addition. We generated a wide range of spatial arrangements of GFP subunits from 11 different oligomeric variants, and determined their X-ray structuresmore » in a total of 33 distinct crystal forms. Furthermore, some of the oligomeric GFP variants show geometric polymorphism depending on conditions, while others show considerable geometric rigidity. Potential future applications of this system are discussed.« less

  17. Application and Evaluation of Control Modes for Risk-Based Engine Performance Enhancements

    NASA Technical Reports Server (NTRS)

    Liu, Yuan; Litt, Jonathan S.; Sowers, T. Shane; Owen, A. Karl (Compiler); Guo, Ten-Huei

    2014-01-01

    The engine control system for civil transport aircraft imposes operational limits on the propulsion system to ensure compliance with safety standards. However, during certain emergency situations, aircraft survivability may benefit from engine performance beyond its normal limits despite the increased risk of failure. Accordingly, control modes were developed to improve the maximum thrust output and responsiveness of a generic high-bypass turbofan engine. The algorithms were designed such that the enhanced performance would always constitute an elevation in failure risk to a consistent predefined likelihood. This paper presents an application of these risk-based control modes to a combined engine/aircraft model. Through computer and piloted simulation tests, the aim is to present a notional implementation of these modes, evaluate their effects on a generic airframe, and demonstrate their usefulness during emergency flight situations. Results show that minimal control effort is required to compensate for the changes in flight dynamics due to control mode activation. The benefits gained from enhanced engine performance for various runway incursion scenarios are investigated. Finally, the control modes are shown to protect against potential instabilities during propulsion-only flight where all aircraft control surfaces are inoperable.

  18. Application and Evaluation of Control Modes for Risk-Based Engine Performance Enhancements

    NASA Technical Reports Server (NTRS)

    Liu, Yuan; Litt, Jonathan S.; Sowers, T. Shane; Owen, A. Karl; Guo, Ten-Huei

    2015-01-01

    The engine control system for civil transport aircraft imposes operational limits on the propulsion system to ensure compliance with safety standards. However, during certain emergency situations, aircraft survivability may benefit from engine performance beyond its normal limits despite the increased risk of failure. Accordingly, control modes were developed to improve the maximum thrust output and responsiveness of a generic high-bypass turbofan engine. The algorithms were designed such that the enhanced performance would always constitute an elevation in failure risk to a consistent predefined likelihood. This paper presents an application of these risk-based control modes to a combined engine/aircraft model. Through computer and piloted simulation tests, the aim is to present a notional implementation of these modes, evaluate their effects on a generic airframe, and demonstrate their usefulness during emergency flight situations. Results show that minimal control effort is required to compensate for the changes in flight dynamics due to control mode activation. The benefits gained from enhanced engine performance for various runway incursion scenarios are investigated. Finally, the control modes are shown to protect against potential instabilities during propulsion-only flight where all aircraft control surfaces are inoperable.

  19. Rocket-Based Combined-Cycle (RBCC) Propulsion Technology Workshop. Tutorial session

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The goal of this workshop was to illuminate the nation's space transportation and propulsion engineering community on the potential of hypersonic combined cycle (airbreathing/rocket) propulsion systems for future space transportation applications. Four general topics were examined: (1) selections from the expansive advanced propulsion archival resource; (2) related propulsion systems technical backgrounds; (3) RBCC engine multimode operations related subsystem background; and (4) focused review of propulsion aspects of current related programs.

  20. Applications of aerospace technology in biology and medicine

    NASA Technical Reports Server (NTRS)

    Brown, J. N.

    1974-01-01

    The results of the medically related activities of the NASA Application Team Program at the Research Triangle Institute are presented. The RTI team, a multidisciplinary team of scientists and engineers, acted as an information and technology interface between NASA and individuals, institutions, and agencies involved in biomedical research and clinical medicine. The Team has identified 40 new problems for investigation, has accomplished 7 technology applications, 6 potential technology application, 4 impacts, has closed 54 old problems, and has a total of 47 problems under active investigation.

  1. Engineering hydrogels as extracellular matrix mimics

    PubMed Central

    Geckil, Hikmet; Xu, Feng; Zhang, Xiaohui; Moon, SangJun

    2010-01-01

    Extracellular matrix (ECM) is a complex cellular environment consisting of proteins, proteoglycans, and other soluble molecules. ECM provides structural support to mammalian cells and a regulatory milieu with a variety of important cell functions, including assembling cells into various tissues and organs, regulating growth and cell–cell communication. Developing a tailored in vitro cell culture environment that mimics the intricate and organized nanoscale meshwork of native ECM is desirable. Recent studies have shown the potential of hydrogels to mimic native ECM. Such an engineered native-like ECM is more likely to provide cells with rational cues for diagnostic and therapeutic studies. The research for novel biomaterials has led to an extension of the scope and techniques used to fabricate biomimetic hydrogel scaffolds for tissue engineering and regenerative medicine applications. In this article, we detail the progress of the current state-of-the-art engineering methods to create cell-encapsulating hydrogel tissue constructs as well as their applications in in vitro models in biomedicine. PMID:20394538

  2. Liposomes in tissue engineering and regenerative medicine

    PubMed Central

    Monteiro, Nelson; Martins, Albino; Reis, Rui L.; Neves, Nuno M.

    2014-01-01

    Liposomes are vesicular structures made of lipids that are formed in aqueous solutions. Structurally, they resemble the lipid membrane of living cells. Therefore, they have been widely investigated, since the 1960s, as models to study the cell membrane, and as carriers for protection and/or delivery of bioactive agents. They have been used in different areas of research including vaccines, imaging, applications in cosmetics and tissue engineering. Tissue engineering is defined as a strategy for promoting the regeneration of tissues for the human body. This strategy may involve the coordinated application of defined cell types with structured biomaterial scaffolds to produce living structures. To create a new tissue, based on this strategy, a controlled stimulation of cultured cells is needed, through a systematic combination of bioactive agents and mechanical signals. In this review, we highlight the potential role of liposomes as a platform for the sustained and local delivery of bioactive agents for tissue engineering and regenerative medicine approaches. PMID:25401172

  3. Engineering organs.

    PubMed

    Atala, Anthony

    2009-10-01

    Applications of regenerative medicine technology may offer novel therapies for patients with injuries, end-stage organ failure, or other clinical problems. Currently, patients suffering from diseased and injured organs can be treated with transplanted organs. However, there is a severe shortage of donor organs that is worsening yearly as the population ages and new cases of organ failure increase. Scientists in the field of regenerative medicine and tissue engineering are now applying the principles of cell transplantation, material science, and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. The stem cell field is also advancing rapidly, opening new avenues for this type of therapy. For example, therapeutic cloning and cellular reprogramming may one day provide a potentially limitless source of cells for tissue engineering applications. Although stem cells are still in the research phase, some therapies arising from tissue engineering endeavors have already entered the clinical setting successfully, indicating the promise regenerative medicine holds for the future.

  4. Application of metabolic engineering for the biotechnological production of L-valine.

    PubMed

    Oldiges, Marco; Eikmanns, Bernhard J; Blombach, Bastian

    2014-07-01

    The branched chain amino acid L-valine is an essential nutrient for higher organisms, such as animals and humans. Besides the pharmaceutical application in parenteral nutrition and as synthon for the chemical synthesis of e.g. herbicides or anti-viral drugs, L-valine is now emerging into the feed market, and significant increase of sales and world production is expected. In accordance, well-known microbial production bacteria, such as Escherichia coli and Corynebacterium glutamicum strains, have recently been metabolically engineered for efficient L-valine production under aerobic or anaerobic conditions, and the respective cultivation and production conditions have been optimized. This review summarizes the state of the art in L-valine biosynthesis and its regulation in E. coli and C. glutamicum with respect to optimal metabolic network for microbial L-valine production, genetic strain engineering and bioprocess development for L-valine production, and finally, it will shed light on emerging technologies that have the potential to accelerate strain and bioprocess engineering in the near future.

  5. Large Animal Models of an In Vivo Bioreactor for Engineering Vascularized Bone.

    PubMed

    Akar, Banu; Tatara, Alexander M; Sutradhar, Alok; Hsiao, Hui-Yi; Miller, Michael; Cheng, Ming-Huei; Mikos, Antonios G; Brey, Eric M

    2018-04-12

    Reconstruction of large skeletal defects is challenging due to the requirement for large volumes of donor tissue and the often complex surgical procedures. Tissue engineering has the potential to serve as a new source of tissue for bone reconstruction, but current techniques are often limited in regards to the size and complexity of tissue that can be formed. Building tissue using an in vivo bioreactor approach may enable the production of appropriate amounts of specialized tissue, while reducing issues of donor site morbidity and infection. Large animals are required to screen and optimize new strategies for growing clinically appropriate volumes of tissues in vivo. In this article, we review both ovine and porcine models that serve as models of the technique proposed for clinical engineering of bone tissue in vivo. Recent findings are discussed with these systems, as well as description of next steps required for using these models, to develop clinically applicable tissue engineering applications.

  6. Low-Engine-Friction Technology for Advanced Natural-Gas Reciprocating Engines

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Victor Wong; Tian Tian; G. Smedley

    This program aims at improving the efficiency of advanced natural-gas reciprocating engines (ANGRE) by reducing piston and piston ring assembly friction without major adverse effects on engine performance, such as increased oil consumption and wear. An iterative process of simulation, experimentation and analysis has been followed towards achieving the goal of demonstrating a complete optimized low-friction engine system. In this program, a detailed set of piston and piston-ring dynamic and friction models have been adapted and applied that illustrate the fundamental relationships among mechanical, surface/material and lubricant design parameters and friction losses. Demonstration of low-friction ring-pack designs in the Waukeshamore » VGF 18GL engine confirmed ring-pack friction reduction of 30-40%, which translates to total engine FEMP (friction mean effective pressure) reduction of 7-10% from the baseline configuration without significantly increasing oil consumption or blow-by flow. The study on surface textures, including roughness characteristics, cross hatch patterns, dimples and grooves have shown that even relatively small-scale changes can have a large effect on ring/liner friction, in some cases reducing FMEP by as much as 30% from a smooth surface case. The measured FMEP reductions were in good agreement with the model predictions. The combined analysis of lubricant and surface design indicates that low-viscosity lubricants can be very effective in reducing friction, subject to component wear for extremely thin oils, which can be mitigated with further lubricant formulation and/or engineered surfaces. Hence a combined approach of lubricant design and appropriate wear reduction offers improved potential for minimum engine friction loss. Testing of low-friction lubricants showed that total engine FMEP reduced by up to {approx}16.5% from the commercial reference oil without significantly increasing oil consumption or blow-by flow. Piston friction studies indicate that a flatter piston with a more flexible skirt, together with optimizing the waviness and film thickness on the piston skirt offer significant friction reduction. Combined with low-friction ring-pack, material and lubricant parameters, a total power cylinder friction reduction of 30-50% is expected, translating to an engine efficiency increase of two percentage points from its current baseline towards the goal of 50% ARES engine efficiency. The design strategies developed in this study have promising potential for application in all modern reciprocating engines as they represent simple, low-cost methods to extract significant fuel savings. The current program has possible spinoffs and applications in other industries as well, including transportation, CHP, and diesel power generation. The progress made in this program has wide engine efficiency implications, and potential deployment of low-friction engine components or lubricants in the near term is quite possible.« less

  7. Properties and applications of chemically functionalized graphene.

    PubMed

    Craciun, M F; Khrapach, I; Barnes, M D; Russo, S

    2013-10-23

    The vast and yet largely unexplored family of graphene materials has great potential for future electronic devices with novel functionalities. The ability to engineer the electrical and optical properties in graphene by chemically functionalizing it with a molecule or adatom is widening considerably the potential applications targeted by graphene. Indeed, functionalized graphene has been found to be the best known transparent conductor or a wide gap semiconductor. At the same time, understanding the mechanisms driving the functionalization of graphene with hydrogen is proving to be of fundamental interest for energy storage devices. Here we discuss recent advances on the properties and applications of chemically functionalized graphene.

  8. Engineering cyanobacteria as photosynthetic feedstock factories

    PubMed Central

    Hays, Stephanie G.; Ducat, Daniel C.

    2018-01-01

    Carbohydrate feedstocks are at the root of bioindustrial production and are needed in greater quantities than ever due to increased prioritization of renewable fuels and reduction of carbon emissions. Cyanobacteria possess a number of features that make them well-suited as an alternative feedstock crop in comparison to traditional, terrestrial plant species. Recent advances in genetic engineering, as well as promising preliminary investigations of cyanobacteria in a number of distinct production regimes have illustrated the potential of these aquatic phototrophs as biosynthetic chasses. Further improvements in strain productivities and design, along with enhanced understanding of photosynthetic metabolism in cyanobacteria may pave the way to translate cyanobacterial theoretical potential into realized application. PMID:24526260

  9. Grouting applications in civil engineering. Volume I and II. [800 references

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Einstein, H.H.; Barvenik, M.J.

    1975-01-01

    A comprehensive description of grouting applications in civil engineering is presented that can serve as a basis for the selection of grouting methods in the borehole sealing problem. The breadth and depth of the study was assured by conducting the main part of the review, the collection and evaluation of information, without specifically considering the borehole sealing problem (but naturally incorporating any aspect of civil engineering applications that could be of potential use). Grouting is very much an art and not a science. In most cases, it is a trial and error procedure where an inexpensive method is initially triedmore » and then a more expensive one is used until the desired results are obtained. Once a desired effect is obtained, it is difficult to credit any one procedure with the success because the results are due to the summation of all the methods used. In many cases, the method that proves successful reflects a small abnormality in the ground or structure rather than its overall characteristics. Hence, successful grouting relies heavily on good engineering judgement and experience, and not on a basic set of standard correlations or equations. 800 references. (JRD)« less

  10. Application of physics engines in virtual worlds

    NASA Astrophysics Data System (ADS)

    Norman, Mark; Taylor, Tim

    2002-03-01

    Dynamic virtual worlds potentially can provide a much richer and more enjoyable experience than static ones. To realize such worlds, three approaches are commonly used. The first of these, and still widely applied, involves importing traditional animations from a modeling system such as 3D Studio Max. This approach is therefore limited to predefined animation scripts or combinations/blends thereof. The second approach involves the integration of some specific-purpose simulation code, such as car dynamics, and is thus generally limited to one (class of) application(s). The third approach involves the use of general-purpose physics engines, which promise to enable a range of compelling dynamic virtual worlds and to considerably speed up development. By far the largest market today for real-time simulation is computer games, revenues exceeding those of the movie industry. Traditionally, the simulation is produced by game developers in-house for specific titles. However, off-the-shelf middleware physics engines are now available for use in games and related domains. In this paper, we report on our experiences of using middleware physics engines to create a virtual world as an interactive experience, and an advanced scenario where artificial life techniques generate controllers for physically modeled characters.

  11. Overview on zein protein: a promising pharmaceutical excipient in drug delivery systems and tissue engineering.

    PubMed

    Labib, Gihan

    2018-01-01

    Natural pharmaceutical excipients have been applied extensively in the past decades owing to their safety and biocompatibility. Zein, a natural protein of plant origin offers great benefit over other synthetic polymers used in controlled drug and biomedical delivery systems. It was used in a variety of medical fields including pharmaceutical and biomedical drug targeting, vaccine, tissue engineering, and gene delivery. Being biodegradable and biocompatible, the current review focuses on the history and the medical application of zein as an attractive still promising biopolymer. Areas covered: The current review gives a broadscope on zein as a still promising protein excipient in different fields. Zein- based drug and biomedical delivery systems are discussed with special focus on current and potential application in controlled drug delivery systems, and tissue engineering. Expert opinion: Zein as a protein of natural origin can still be considered a promising polymer in the field of drug delivery systems as well as in tissue engineering. Although different researchers spotted light on zein application in different industrial fields extensively, the feasibility of its use in the field of drug delivery replenished by investigators in recent years has not yet been fully approached.

  12. The self-assembling process and applications in tissue engineering

    PubMed Central

    Lee, Jennifer K.; Link, Jarrett M.; Hu, Jerry C. Y.; Athanasiou, Kyriacos A.

    2018-01-01

    Tissue engineering strives to create neotissues capable of restoring function. Scaffold-free technologies have emerged that can recapitulate native tissue function without the use of an exogenous scaffold. This chapter will survey, in particular, the self-assembling and self-organization processes as scaffold-free techniques. Characteristics and benefits of each process are described, and key examples of tissues created using these scaffold-free processes are examined to provide guidance for future tissue engineering developments. This chapter aims to explore the potential of self-assembly and self-organization scaffold-free approaches, detailing the recent progress in the in vitro tissue engineering of biomimetic tissues with these methods, toward generating functional tissue replacements. PMID:28348174

  13. Operationally efficient propulsion system study (OEPSS) data book. Volume 9; Preliminary Development Plan for an Integrated Booster Propulsion Module (BPM)

    NASA Technical Reports Server (NTRS)

    DiBlasi, Angelo G.

    1992-01-01

    A preliminary development plan for an integrated propulsion module (IPM) is described. The IPM, similar to the Space Transportation Main engine (STME) engine, is applicable to the Advanced Launch System (ALS) baseline vehicle. The same STME development program ground rules and time schedule were assumed for the IPM. However, the unique advantages of testing an integrated engine element, in terms of reduced number of hardware and number of system and reliability tests, compared to single standalone engine and MPTA, are highlighted. The potential ability of the IPM to meet the ALS program goals for robustness, operability and reliability is emphasized.

  14. Power system applications of high temperature superconductors

    NASA Astrophysics Data System (ADS)

    Garlick, W. G.

    This paper presents an overview of potential applications for high temperature superconductors (HTSs) in the field of power engineering. For almost 10 years material scientists, chemists and physicists have had the freedom to find, explore and characterize the properties of new HTS materials. 10 years is not a long time in the development of a revolutionary technology, but it seems like an age to the engineer who has recognized its potential and waits impatiently for the technology to stabilize in order to apply it. Largely due to Government and Industry partnerships, only a few years after the discovery of HTS, electrical power applications based on HTS are now being designed and tested. These applications offer many benefits to the resident electrical system: increased energy efficiency, smaller equipment, reduced emissions, increased stability and reliability, deferred expansion and flexible transmission and distribution. They have a common focus: lower electricity costs, improved environmental quality and more competitive products for a global market. For HTS to become a commercial success, the development of materials technologies is necessary but not sufficient on its own; the development of a capability to design and manufacture products that use the materials is also fundamental to a viable and successful industrial base.

  15. Glycopolymer functionalization of engineered spider silk protein-based materials for improved cell adhesion.

    PubMed

    Hardy, John G; Pfaff, André; Leal-Egaña, Aldo; Müller, Axel H E; Scheibel, Thomas R

    2014-07-01

    Silk protein-based materials are promising biomaterials for application as tissue scaffolds, due to their processability, biocompatibility, and biodegradability. The preparation of films composed of an engineered spider silk protein (eADF4(C16)) and their functionalization with glycopolymers are described. The glycopolymers bind proteins found in the extracellular matrix, providing a biomimetic coating on the films that improves cell adhesion to the surfaces of engineered spider silk films. Such silk-based materials have potential as coatings for degradable implantable devices. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Surface functionalization of nanobiomaterials for application in stem cell culture, tissue engineering, and regenerative medicine.

    PubMed

    Rana, Deepti; Ramasamy, Keerthana; Leena, Maria; Jiménez, Constanza; Campos, Javier; Ibarra, Paula; Haidar, Ziyad S; Ramalingam, Murugan

    2016-05-01

    Stem cell-based approaches offer great application potential in tissue engineering and regenerative medicine owing to their ability of sensing the microenvironment and respond accordingly (dynamic behavior). Recently, the combination of nanobiomaterials with stem cells has paved a great way for further exploration. Nanobiomaterials with engineered surfaces could mimic the native microenvironment to which the seeded stem cells could adhere and migrate. Surface functionalized nanobiomaterial-based scaffolds could then be used to regulate or control the cellular functions to culture stem cells and regenerate damaged tissues or organs. Therefore, controlling the interactions between nanobiomaterials and stem cells is a critical factor. However, surface functionalization or modification techniques has provided an alternative approach for tailoring the nanobiomaterials surface in accordance to the physiological surrounding of a living cells; thereby, enhancing the structural and functional properties of the engineered tissues and organs. Currently, there are a variety of methods and technologies available to modify the surface of biomaterials according to the specific cell or tissue properties to be regenerated. This review highlights the trends in surface modification techniques for nanobiomaterials and the biological relevance in stem cell-based tissue engineering and regenerative medicine. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:554-567, 2016. © 2016 American Institute of Chemical Engineers.

  17. Advanced Turbine Technology Applications Project (ATTAP) 1993 annual report

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This report summarizes work performed by AlliedSignal Engines, a unit of AlliedSignal Aerospace Company, during calendar year 1993, toward development and demonstration of structural ceramic technology for automotive gas turbine engines. This work was performed for the U.S. Department of Energy (DOE) under National Aeronautics and Space Administration (NASA) Contract DEN3-335, Advanced Turbine Technology Applications Project (ATFAP). During 1993, the test bed used to demonstrate ceramic technology was changed from the AlliedSignal Engines/Garrett Model AGT101 regenerated gas turbine engine to the Model 331-200(CT) engine. The 331-200(CT) ceramic demonstrator is a fully-developed test platform based on the existing production AlliedSignal 331-200(ER) gas turbine auxiliary power unit (APU), and is well suited to evaluating ceramic turbine blades and nozzles. In addition, commonality of the 331-200(CT) engine with existing gas turbine APU's in commercial service provides the potential for field testing of ceramic components. The 1993 ATTAP activities emphasized design modifications of the 331-200 engine test bed to accommodate ceramic first-stage turbine nozzles and blades, fabrication of the ceramic components, ceramic component proof and rig tests, operational tests of the test bed equipped with the ceramic components, and refinement of critical ceramic design technologies.

  18. Impact of gate engineering in enhancement mode n++GaN/InAlN/AlN/GaN HEMTs

    NASA Astrophysics Data System (ADS)

    Adak, Sarosij; Swain, Sanjit Kumar; Rahaman, Hafizur; Sarkar, Chandan Kumar

    2016-12-01

    This paper illustrate the effect of gate material engineering on the performance of enhancement mode n++GaN/InAlN/AlN/GaN high electron mobility transistors (HEMTs). A comparative analysis of key device parameters is discussed for the Triple Material Gate (TMG), Dual Material Gate (DMG) and the Single Material Gate (SMG) structure HEMTs by considering the same device dimensions. The simulation results shows that an significant improvement is noticed in the key analysis parameters such as drain current (Id), transconductance (gm), cut off frequency (fT), RF current gain, maximum cut off frequency (fmax) and RF power gain of the gate material engineered devices with respect to SMG normally off n++GaN/InAlN/AlN/GaN HEMTs. This improvement is due to the existence of the perceivable step in the surface potential along the channel which successfully screens the drain potential variation in the source side of the channel for the gate engineering devices. The analysis suggested that the proposed TMG and DMG engineered structure enhancement mode n++GaN/InAlN/AlN/GaN HEMTs can be considered as a potential device for future high speed, microwave and digital application.

  19. Nanotoxicology: the present and the future

    EPA Science Inventory

    Engineered nanomaterials, due to their unique properties, can enable novel applications, but at the same time raise concern about potential toxicity. The knowledge of nanotoxicology developed quickly in recent years on not only the biological effects of nanomaterials, but also on...

  20. Aggregation and Deposition of C60 in Aqueous Systems

    EPA Science Inventory

    The extremely low water solubility of many fullerenes precludes aqueous solution processing for engineering applications and minimizes the potential for fullerene environmental effects in aqueous environments. However, studies have shown that C60 fullerene can form stable colloi...

  1. Vitro Pulmonary Toxicity of Metal Oxide Nanoparticles

    EPA Science Inventory

    The diversity of engineered-nanomaterials and their applications as well as potential unknown health effects of these novel materials are significant challenges to assessing the health risks of nanotechnology. An integrated multi-tier testing strategy (www.epa.gov/nanoscience/) ...

  2. A Knowledge-Based System Developer for aerospace applications

    NASA Technical Reports Server (NTRS)

    Shi, George Z.; Wu, Kewei; Fensky, Connie S.; Lo, Ching F.

    1993-01-01

    A prototype Knowledge-Based System Developer (KBSD) has been developed for aerospace applications by utilizing artificial intelligence technology. The KBSD directly acquires knowledge from domain experts through a graphical interface then builds expert systems from that knowledge. This raises the state of the art of knowledge acquisition/expert system technology to a new level by lessening the need for skilled knowledge engineers. The feasibility, applicability , and efficiency of the proposed concept was established, making a continuation which would develop the prototype to a full-scale general-purpose knowledge-based system developer justifiable. The KBSD has great commercial potential. It will provide a marketable software shell which alleviates the need for knowledge engineers and increase productivity in the workplace. The KBSD will therefore make knowledge-based systems available to a large portion of industry.

  3. Review: Potential Strength of Fly Ash-Based Geopolymer Paste with Substitution of Local Waste Materials with High-Temperature Effect

    NASA Astrophysics Data System (ADS)

    Subekti, S.; Bayuaji, R.; Darmawan, M. S.; Husin, N. A.; Wibowo, B.; Anugraha, B.; Irawan, S.; Dibiantara, D.

    2017-11-01

    This research provided an overview of the potential fly ash based geopolymer paste for application in building construction. Geopolymer paste with various variations of fly ash substitution with local waste material and high-temperature influence exploited with the fresh and hardened condition. The local waste material which utilized for this study were sandblasting waste, carbide waste, shell powder, bagasse ash, rice husk and bottom ash. The findings of this study indicated that fly-based geopolymer paste with local waste material substitution which had high-temperature influence ash showed a similar nature of OPC binders potentially used in civil engineering applications.

  4. Two-photon excitation based photochemistry and neural imaging

    NASA Astrophysics Data System (ADS)

    Hatch, Kevin Andrew

    Two-photon microscopy is a fluorescence imaging technique which provides distinct advantages in three-dimensional cellular and molecular imaging. The benefits of this technology may extend beyond imaging capabilities through exploitation of the quantum processes responsible for fluorescent events. This study utilized a two-photon microscope to investigate a synthetic photoreactive collagen peptidomimetic, which may serve as a potential material for tissue engineering using the techniques of two-photon photolysis and two-photon polymerization. The combination of these techniques could potentially be used to produce a scaffold for the vascularization of engineered three-dimensional tissues in vitro to address the current limitations of tissue engineering. Additionally, two-photon microscopy was used to observe the effects of the application of the neurotransmitter dopamine to the mushroom body neural structures of Drosophila melanogaster to investigate dopamine's connection to cognitive degeneration.

  5. Nanoscale Engineering of Designer Cellulosomes.

    PubMed

    Gunnoo, Melissabye; Cazade, Pierre-André; Galera-Prat, Albert; Nash, Michael A; Czjzek, Mirjam; Cieplak, Marek; Alvarez, Beatriz; Aguilar, Marina; Karpol, Alon; Gaub, Hermann; Carrión-Vázquez, Mariano; Bayer, Edward A; Thompson, Damien

    2016-07-01

    Biocatalysts showcase the upper limit obtainable for high-speed molecular processing and transformation. Efforts to engineer functionality in synthetic nanostructured materials are guided by the increasing knowledge of evolving architectures, which enable controlled molecular motion and precise molecular recognition. The cellulosome is a biological nanomachine, which, as a fundamental component of the plant-digestion machinery from bacterial cells, has a key potential role in the successful development of environmentally-friendly processes to produce biofuels and fine chemicals from the breakdown of biomass waste. Here, the progress toward so-called "designer cellulosomes", which provide an elegant alternative to enzyme cocktails for lignocellulose breakdown, is reviewed. Particular attention is paid to rational design via computational modeling coupled with nanoscale characterization and engineering tools. Remaining challenges and potential routes to industrial application are put forward. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. A review of the economic implications of the National Academy of Engineering 1974 study of the potential application of space systems

    NASA Technical Reports Server (NTRS)

    1975-01-01

    User benefits resulting from the application of space systems to previously described application areas were identified, and methods to assign priorities to application areas and to quantify the benefits were described. The following areas were selected for in-depth review: communications, materials processing in space, weather and climate, and institutional arrangements for space applications. Recommendations concerning studies that should be undertaken to develop a more precise understanding of the source and magnitude of the realizable economic benefits were also presented.

  7. Engineering Pseudomonas for phenazine biosynthesis, regulation, and biotechnological applications: a review.

    PubMed

    Bilal, Muhammad; Guo, Shuqi; Iqbal, Hafiz M N; Hu, Hongbo; Wang, Wei; Zhang, Xuehong

    2017-10-03

    Pseudomonas strains are increasingly attracting considerable attention as a valuable bacterial host both for basic and applied research. It has been considered as a promising candidate to produce a variety of bioactive secondary metabolites, particularly phenazines. Apart from the biotechnological perspective, these aromatic compounds have the notable potential to inhibit plant-pathogenic fungi and thus are useful in controlling plant diseases. Nevertheless, phenazines production is quite low by the wild-type strains that necessitated its yield improvement for large-scale agricultural applications. Metabolic engineering approaches with the advent of plentiful information provided by systems-level genomic and transcriptomic analyses enabled the development of new biological agents functioning as potential cell factories for producing the desired level of value-added bioproducts. This study presents an up-to-date overview of recombinant Pseudomonas strains as the preferred choice of host organisms for the biosynthesis of natural phenazines. The biosynthetic pathway and regulatory mechanism involved in the phenazine biosynthesis are comprehensively discussed. Finally, a summary of biological functionalities and biotechnological applications of the phenazines is also provided.

  8. Bone tissue engineering using silica-based mesoporous nanobiomaterials:Recent progress.

    PubMed

    Shadjou, Nasrin; Hasanzadeh, Mohammad

    2015-10-01

    Bone disorders are of significant concern due to increase in the median age of our population. It is in this context that tissue engineering has been emerging as a valid approach to the current therapies for bone regeneration/substitution. Tissue-engineered bone constructs have the potential to alleviate the demand arising from the shortage of suitable autograft and allograft materials for augmenting bone healing. Silica based mesostructured nanomaterials possessing pore sizes in the range 2-50 nm and surface reactive functionalities have elicited immense interest due to their exciting prospects in bone tissue engineering. In this review we describe application of silica-based mesoporous nanomaterials for bone tissue engineering. We summarize the preparation methods, the effect of mesopore templates and composition on the mesopore-structure characteristics, and different forms of these materials, including particles, fibers, spheres, scaffolds and composites. Also, the effect of structural and textural properties of mesoporous materials on development of new biomaterials for production of bone implants and bone cements was discussed. Also, application of different mesoporous materials on construction of manufacture 3-dimensional scaffolds for bone tissue engineering was discussed. It begins by giving the reader a brief background on tissue engineering, followed by a comprehensive description of all the relevant components of silica-based mesoporous biomaterials on bone tissue engineering, going from materials to scaffolds and from cells to tissue engineering strategies that will lead to "engineered" bone. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Chemical Reactive Anchoring Lipids with Different Performance for Cell Surface Re-engineering Application

    PubMed Central

    2018-01-01

    Introduction of selectively chemical reactive groups at the cell surface enables site-specific cell surface labeling and modification opportunity, thus facilitating the capability to study the cell surface molecular structure and function and the molecular mechanism it underlies. Further, it offers the opportunity to change or improve a cell’s functionality for interest of choice. In this study, two chemical reactive anchor lipids, phosphatidylethanolamine–poly(ethylene glycol)–dibenzocyclooctyne (DSPE–PEG2000–DBCO) and cholesterol–PEG–dibenzocyclooctyne (CHOL–PEG2000–DBCO) were synthesized and their potential application for cell surface re-engineering via lipid fusion were assessed with RAW 264.7 cells as a model cell. Briefly, RAW 264.7 cells were incubated with anchor lipids under various concentrations and at different incubation times. The successful incorporation of the chemical reactive anchor lipids was confirmed by biotinylation via copper-free click chemistry, followed by streptavidin-fluorescein isothiocyanate binding. In comparison, the cholesterol-based anchor lipid afforded a higher cell membrane incorporation efficiency with less internalization than the phospholipid-based anchor lipid. Low cytotoxicity of both anchor lipids upon incorporation into the RAW 264.7 cells was observed. Further, the cell membrane residence time of the cholesterol-based anchor lipid was evaluated with confocal microscopy. This study suggests the potential cell surface re-engineering applications of the chemical reactive anchor lipids. PMID:29503972

  10. Polypyrrole/Alginate Hybrid Hydrogels: Electrically Conductive and Soft Biomaterials for Human Mesenchymal Stem Cell Culture and Potential Neural Tissue Engineering Applications.

    PubMed

    Yang, Sumi; Jang, LindyK; Kim, Semin; Yang, Jongcheol; Yang, Kisuk; Cho, Seung-Woo; Lee, Jae Young

    2016-11-01

    Electrically conductive biomaterials that can efficiently deliver electrical signals to cells or improve electrical communication among cells have received considerable attention for potential tissue engineering applications. Conductive hydrogels are desirable particularly for neural applications, as they can provide electrical signals and soft microenvironments that can mimic native nerve tissues. In this study, conductive and soft polypyrrole/alginate (PPy/Alg) hydrogels are developed by chemically polymerizing PPy within ionically cross-linked alginate hydrogel networks. The synthesized hydrogels exhibit a Young's modulus of 20-200 kPa. Electrical conductance of the PPy/Alg hydrogels could be enhanced by more than one order of magnitude compared to that of pristine alginate hydrogels. In vitro studies with human bone marrow-derived mesenchymal stem cells (hMSCs) reveal that cell adhesion and growth are promoted on the PPy/Alg hydrogels. Additionally, the PPy/Alg hydrogels support and greatly enhance the expression of neural differentiation markers (i.e., Tuj1 and MAP2) of hMSCs compared to tissue culture plate controls. Subcutaneous implantation of the hydrogels for eight weeks induces mild inflammatory reactions. These soft and conductive hydrogels will serve as a useful platform to study the effects of electrical and mechanical signals on stem cells and/or neural cells and to develop multifunctional neural tissue engineering scaffolds. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Structure-based engineering of a pectate lyase with improved specific activity for ramie degumming.

    PubMed

    Zhou, Zhanping; Liu, Yang; Chang, Zhenying; Wang, Huilin; Leier, André; Marquez-Lago, Tatiana T; Ma, Yanhe; Li, Jian; Song, Jiangning

    2017-04-01

    Biotechnological applications of microbial pectate lyases (Pels) in plant fiber processing are promising, eco-friendly substitutes for conventional chemical degumming processes. However, to potentiate the enzymes' use for industrial applications, resolving the molecular structure to elucidate catalytic mechanisms becomes necessary. In this manuscript, we report the high resolution (1.45 Å) crystal structure of pectate lyase (pelN) from Paenibacillus sp. 0602 in apo form. Through sequence alignment and structural superposition with other members of the polysaccharide lyase (PL) family 1 (PL1), we determined that pelN shares the characteristic right-handed β-helix and is structurally similar to other members of the PL1 family, while exhibiting key differences in terms of catalytic and substrate binding residues. Then, based on information from structure alignments with other PLs, we engineered a novel pelN. Our rational design yielded a pelN mutant with a temperature for enzymatic activity optimally shifted from 67.5 to 60 °C. Most importantly, this pelN mutant displayed both higher specific activity and ramie fiber degumming ability when compared with the wild-type enzyme. Altogether, our rational design method shows great potential for industrial applications. Moreover, we expect the reported high-resolution crystal structure to provide a solid foundation for future rational, structure-based engineering of genetically enhanced pelNs.

  12. Dual nozzle design update. [on liquid rocket engines for advanced earth-to-orbit transportation systems

    NASA Technical Reports Server (NTRS)

    Obrien, C. J.

    1982-01-01

    Dual-nozzle engines, such as the dual-throat and dual-expander engines, are being evaluated for advanced earth-to-orbit transportation systems. Potential derivatives of the Space Shuttle and completely new vehicles might benefit from these advanced engines. In this paper, progress in the design of single-fuel and dual-fuel dual-nozzle engines is summarized. Dual-nozzle engines include those burning propellants such as LOX/RP-1/LH2, LOX/LC3H8/LH2, LOX/LCH4/LH2, LOX/LH2/LH2, LOX/LCH4/LCH4, LOX/LC3H8/C3H8 and N2O4/MMH/LH2. Engine data are applicable for thrust levels from 200,000 through 670,000 lbF. The results indicate that several versions of these engines utilize state-of-the-art technology and that even advanced versions of these engines do not require a major breakthrough in technology.

  13. Objectively Determining the Educational Potential of Computer and Video-Based Courseware; or, Producing Reliable Evaluations Despite the Dog and Pony Show.

    ERIC Educational Resources Information Center

    Barrett, Andrew J.; And Others

    The Center for Interactive Technology, Applications, and Research at the College of Engineering of the University of South Florida (Tampa) has developed objective and descriptive evaluation models to assist in determining the educational potential of computer and video courseware. The computer-based courseware evaluation model and the video-based…

  14. Multifunctional magnetic nanostructured hardystonite scaffold for hyperthermia, drug delivery and tissue engineering applications.

    PubMed

    Farzin, Ali; Fathi, Mohammadhossein; Emadi, Rahmatollah

    2017-01-01

    Hyperthermia and local drug delivery have been proposed as potential therapeutic approaches for killing cancer cells. The development of bioactive materials such as Hardystonite (HT) with magnetic and drug delivery properties can potentially meet this target. This new class of magnetic bioceramic can replace the widely used magnetic iron oxide nanoparticles, whose long-term biocompatibility is not clear. Magnetic HT can be potentially employed to develop new ceramic scaffolds for bone surgery and anticancer therapies. With this in mind, a synthesis procedure was developed to prepare multifunctional bioactive scaffold for tissue engineering, hyperthermia and drug delivery applications. To this end, iron (Fe 3+ )-containing HT scaffolds were prepared. The effect of Fe on biological, magnetic and drug delivery properties of HT scaffolds were investigated. The results showed that obtained Fe-HT is bioactive and magnetic with no magnetite or maghemite as secondary phases. The Fe-HT scaffolds obtained also possessed high specific surface areas and demonstrated sustained drug delivery. These results potentially open new aspects for biomaterials aimed at regeneration of large-bone defects caused by malignant bone tumors through a combination of hyperthermia, local drug delivery and osteoconductivity. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Application of Function-Failure Similarity Method to Rotorcraft Component Design

    NASA Technical Reports Server (NTRS)

    Roberts, Rory A.; Stone, Robert E.; Tumer, Irem Y.; Clancy, Daniel (Technical Monitor)

    2002-01-01

    Performance and safety are the top concerns of high-risk aerospace applications at NASA. Eliminating or reducing performance and safety problems can be achieved with a thorough understanding of potential failure modes in the designs that lead to these problems. The majority of techniques use prior knowledge and experience as well as Failure Modes and Effects as methods to determine potential failure modes of aircraft. During the design of aircraft, a general technique is needed to ensure that every potential failure mode is considered, while avoiding spending time on improbable failure modes. In this work, this is accomplished by mapping failure modes to specific components, which are described by their functionality. The failure modes are then linked to the basic functions that are carried within the components of the aircraft. Using this technique, designers can examine the basic functions, and select appropriate analyses to eliminate or design out the potential failure modes. The fundamentals of this method were previously introduced for a simple rotating machine test rig with basic functions that are common to a rotorcraft. In this paper, this technique is applied to the engine and power train of a rotorcraft, using failures and functions obtained from accident reports and engineering drawings.

  16. Overview of the 1985 NASA Lewis Research Center SP-100 free-piston Stirling engine activities

    NASA Technical Reports Server (NTRS)

    Slaby, J.

    1985-01-01

    This effort is keyed on the design, fabrication, assembly, and testing of a 25 kWe Stirling space-power technology-feasibility demonstrator engine. Another facet of the SP-100 project covers the status of a 9000-hr endurance test conducted on a 2 kWe free-piston Stirling/linear alternator system employing hydrostatic gas bearings. Dynamic balancing of the RE-1000 engine (a 1 kWe free-piston Stirling engine) using a passive dynamic absorber will be discussed along with the results of a parametric study showing the relationships of Stirling power converter specific weight and efficiency as functions of Stirling engine heater to cooler temperature ratio. Planned tests will be described covering a hydrodynamic gas bearing concept for potential SP-100 application.

  17. Generation of genetically-engineered animals using engineered endonucleases.

    PubMed

    Lee, Jong Geol; Sung, Young Hoon; Baek, In-Jeoung

    2018-05-17

    The key to successful drug discovery and development is to find the most suitable animal model of human diseases for the preclinical studies. The recent emergence of engineered endonucleases is allowing for efficient and precise genome editing, which can be used to develop potentially useful animal models for human diseases. In particular, zinc finger nucleases, transcription activator-like effector nucleases, and the clustered regularly interspaced short palindromic repeat systems are revolutionizing the generation of diverse genetically-engineered experimental animals including mice, rats, rabbits, dogs, pigs, and even non-human primates that are commonly used for preclinical studies of the drug discovery. Here, we describe recent advances in engineered endonucleases and their application in various laboratory animals. We also discuss the importance of genome editing in animal models for more closely mimicking human diseases.

  18. Optical sensor system for time-resolved quantification of methane concentrations: Validation measurements in a rapid compression machine

    NASA Astrophysics Data System (ADS)

    Bauke, Stephan; Golibrzuch, Kai; Wackerbarth, Hainer; Fendt, Peter; Zigan, Lars; Seefeldt, Stefan; Thiele, Olaf; Berg, Thomas

    2018-05-01

    Lowering greenhouse gas emissions is one of the most challenging demands of today's society. Especially, the automotive industry struggles with the development of more efficient internal combustion (IC) engines. As an alternative to conventional fuels, methane has the potential for a significant emission reduction. In methane fuelled engines, the process of mixture formation, which determines the properties of combustion after ignition, differs significantly from gasoline and diesel engines and needs to be understood and controlled in order to develop engines with high efficiency. This work demonstrates the development of a gas sensing system that can serve as a diagnostic tool for measuring crank-angle resolved relative air-fuel ratios in methane-fuelled near-production IC engines. By application of non-dispersive infrared absorption spectroscopy at two distinct spectral regions in the ν3 absorption band of methane around 3.3 μm, the system is able to determine fuel density and temperature simultaneously. A modified spark plug probe allows for straightforward application at engine test stations. Here, the application of the detection system in a rapid compression machine is presented, which enables validation and characterization of the system on well-defined gas mixtures under engine-like dynamic conditions. In extension to a recent proof-of-principle study, a refined data analysis procedure is introduced that allows the correction of artefacts originating from mechanical distortions of the sensor probe. In addition, the measured temperatures are compared to data obtained with a commercially available system based on the spectrally resolved detection of water absorption in the near infrared.

  19. Thermal inkjet printing in tissue engineering and regenerative medicine.

    PubMed

    Cui, Xiaofeng; Boland, Thomas; D'Lima, Darryl D; Lotz, Martin K

    2012-08-01

    With the advantages of high throughput, digital control, and highly accurate placement of cells and biomaterial scaffold to the desired 2D and 3D locations, bioprinting has great potential to develop promising approaches in translational medicine and organ replacement. The most recent advances in organ and tissue bioprinting based on the thermal inkjet printing technology are described in this review. Bioprinting has no or little side effect to the printed mammalian cells and it can conveniently combine with gene transfection or drug delivery to the ejected living systems during the precise placement for tissue construction. With layer-by-layer assembly, 3D tissues with complex structures can be printed using scanned CT or MRI images. Vascular or nerve systems can be enabled simultaneously during the organ construction with digital control. Therefore, bioprinting is the only solution to solve this critical issue in thick and complex tissues fabrication with vascular system. Collectively, bioprinting based on thermal inkjet has great potential and broad applications in tissue engineering and regenerative medicine. This review article introduces some important patents related to bioprinting of living systems and the applications of bioprinting in tissue engineering field.

  20. Rapid Object Detection Systems, Utilising Deep Learning and Unmanned Aerial Systems (uas) for Civil Engineering Applications

    NASA Astrophysics Data System (ADS)

    Griffiths, D.; Boehm, J.

    2018-05-01

    With deep learning approaches now out-performing traditional image processing techniques for image understanding, this paper accesses the potential of rapid generation of Convolutional Neural Networks (CNNs) for applied engineering purposes. Three CNNs are trained on 275 UAS-derived and freely available online images for object detection of 3m2 segments of railway track. These includes two models based on the Faster RCNN object detection algorithm (Resnet and Incpetion-Resnet) as well as the novel onestage Focal Loss network architecture (Retinanet). Model performance was assessed with respect to three accuracy metrics. The first two consisted of Intersection over Union (IoU) with thresholds 0.5 and 0.1. The last assesses accuracy based on the proportion of track covered by object detection proposals against total track length. In under six hours of training (and two hours of manual labelling) the models detected 91.3 %, 83.1 % and 75.6 % of track in the 500 test images acquired from the UAS survey Retinanet, Resnet and Inception-Resnet respectively. We then discuss the potential for such applications of such systems within the engineering field for a range of scenarios.

  1. Proton Exchange Membrane (PEM) Fuel Cell Status and Remaining Challenges for Manned Space-Flight Applications

    NASA Technical Reports Server (NTRS)

    Reaves, Will F.; Hoberecht, Mark A.

    2003-01-01

    The Fuel Cell has been used for manned space flight since the Gemini program. Its power output and water production capability over long durations for the mass and volume are critical for manned space-flight requirements. The alkaline fuel cell used on the Shuttle, while very reliable and capable for it s application, has operational sensitivities, limited life, and an expensive recycle cost. The PEM fuel cell offers many potential improvements in those areas. NASA Glenn Research Center is currently leading a PEM fuel cell development and test program intended to move the technology closer to the point required for manned space-flight consideration. This paper will address the advantages of PEM fuel cell technology and its potential for future space flight as compared to existing alkaline fuel cells. It will also cover the technical hurdles that must be overcome. In addition, a description of the NASA PEM fuel cell development program will be presented, and the current status of this effort discussed. The effort is a combination of stack and ancillary component hardware development, culminating in breadboard and engineering model unit assembly and test. Finally, a detailed roadmap for proceeding fiom engineering model hardware to qualification and flight hardware will be proposed. Innovative test engineering and potential payload manifesting may be required to actually validate/certify a PEM fuel cell for manned space flight.

  2. System Detects Vibrational Instabilities

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J., Jr.

    1990-01-01

    Sustained vibrations at two critical frequencies trigger diagnostic response or shutdown. Vibration-analyzing electronic system detects instabilities of combustion in rocket engine. Controls pulse-mode firing of engine and identifies vibrations above threshold amplitude at 5.9 and/or 12kHz. Adapted to other detection and/or control schemes involving simultaneous real-time detection of signals above or below preset amplitudes at two or more specified frequencies. Potential applications include rotating machinery and encoders and decoders in security systems.

  3. Coupling artificial intelligence and numerical computation for engineering design (Invited paper)

    NASA Astrophysics Data System (ADS)

    Tong, S. S.

    1986-01-01

    The possibility of combining artificial intelligence (AI) systems and numerical computation methods for engineering designs is considered. Attention is given to three possible areas of application involving fan design, controlled vortex design of turbine stage blade angles, and preliminary design of turbine cascade profiles. Among the AI techniques discussed are: knowledge-based systems; intelligent search; and pattern recognition systems. The potential cost and performance advantages of an AI-based design-generation system are discussed in detail.

  4. Model-Based Systems Engineering With the Architecture Analysis and Design Language (AADL) Applied to NASA Mission Operations

    NASA Technical Reports Server (NTRS)

    Munoz Fernandez, Michela Miche

    2014-01-01

    The potential of Model Model Systems Engineering (MBSE) using the Architecture Analysis and Design Language (AADL) applied to space systems will be described. AADL modeling is applicable to real-time embedded systems- the types of systems NASA builds. A case study with the Juno mission to Jupiter showcases how this work would enable future missions to benefit from using these models throughout their life cycle from design to flight operations.

  5. Functionalized hybrid nanofibers to mimic native ECM for tissue engineering applications

    NASA Astrophysics Data System (ADS)

    Karuppuswamy, Priyadharsini; Venugopal, Jayarama Reddy; Navaneethan, Balchandar; Laiva, Ashang Luwang; Sridhar, Sreepathy; Ramakrishna, Seeram

    2014-12-01

    Nanotechnology being one of the most promising technologies today shows an extremely huge potential in the field of tissue engineering to mimic the porous topography of natural extracellular matrix (ECM). Natural polymers are incorporated into the synthetic polymers to fabricate functionalized hybrid nanofibrous scaffolds, which improve cell and tissue compatibility. The present study identified the biopolymers - aloe vera, silk fibroin and curcumin incorporated into polycaprolactone (PCL) as suitable substrates for tissue engineering. Different combinations of PCL with natural polymers - PCL/aloe vera, PCL/silk fibroin, PCL/aloe vera/silk fibroin, PCL/aloe vera/silk fibroin/curcumin were electrospun into nanofibrous scaffolds. The fabricated two dimensional nanofibrous scaffolds showed high surface area, appropriate mechanical properties, hydrophilicity and porosity, required for the regeneration of diseased tissues. The nanofibrous scaffolds were characterized by Scanning electron microscope (SEM), porometry, Instron tensile tester, VCA optima contact angle measurement and FTIR to analyze the fiber diameter and morphology, porosity and pore size distribution, mechanical strength, wettability, chemical bonds and functional groups, respectively. The average fiber diameter of obtained fibers ranged from 250 nm to 350 nm and the tensile strength of PCL scaffolds at 4.49 MPa increased upto 8.3 MPa for PCL/silk fibroin scaffolds. Hydrophobicity of PCL decreased with the incorporation of natural polymers, especially for PCL/aloe vera scaffolds. The properties of as-spun nanofiber scaffolds showed their potential as promising scaffold materials in tissue engineering applications.

  6. Business logic for geoprocessing of distributed geodata

    NASA Astrophysics Data System (ADS)

    Kiehle, Christian

    2006-12-01

    This paper describes the development of a business-logic component for the geoprocessing of distributed geodata. The business logic acts as a mediator between the data and the user, therefore playing a central role in any spatial information system. The component is used in service-oriented architectures to foster the reuse of existing geodata inventories. Based on a geoscientific case study of groundwater vulnerability assessment and mapping, the demands for such architectures are identified with special regard to software engineering tasks. Methods are derived from the field of applied Geosciences (Hydrogeology), Geoinformatics, and Software Engineering. In addition to the development of a business logic component, a forthcoming Open Geospatial Consortium (OGC) specification is introduced: the OGC Web Processing Service (WPS) specification. A sample application is introduced to demonstrate the potential of WPS for future information systems. The sample application Geoservice Groundwater Vulnerability is described in detail to provide insight into the business logic component, and demonstrate how information can be generated out of distributed geodata. This has the potential to significantly accelerate the assessment and mapping of groundwater vulnerability. The presented concept is easily transferable to other geoscientific use cases dealing with distributed data inventories. Potential application fields include web-based geoinformation systems operating on distributed data (e.g. environmental planning systems, cadastral information systems, and others).

  7. HEMOXCell, a New Oxygen Carrier Usable as an Additive for Mesenchymal Stem Cell Culture in Platelet Lysate-Supplemented Media.

    PubMed

    Le Pape, Fiona; Cosnuau-Kemmat, Lucie; Richard, Gaëlle; Dubrana, Frédéric; Férec, Claude; Zal, Franck; Leize, Elisabeth; Delépine, Pascal

    2017-04-01

    Human mesenchymal stem cells (MSCs) are promising candidates for therapeutic applications such as tissue engineering. However, one of the main challenges is to improve oxygen supply to hypoxic areas to reduce oxygen gradient formation while preserving MSC differentiation potential and viability. For this purpose, a marine hemoglobin, HEMOXCell, was evaluated as an oxygen carrier for culturing human bone marrow MSCs in vitro for future three-dimensional culture applications. Impact of HEMOXCell on cell growth and viability was assessed in human platelet lysate (hPL)-supplemented media. Maintenance of MSC features, such as multipotency and expression of MSC specific markers, was further investigated by biochemical assays and flow cytometry analysis. Our experimental results highlight its oxygenator potential and indicate that an optimal concentration of 0.025 g/L HEMOXCell induces a 25%-increase of the cell growth rate, preserves MSC phenotype, and maintains MSC differentiation properties; a two-fold higher concentration induces cell detachment without altering cell viability. Our data suggest the potential interest of HEMOXCell as a natural oxygen carrier for tissue engineering applications to oxygenate hypoxic areas and to maintain cell viability, functions and "stemness." These features will be further tested within three-dimensional scaffolds. © 2017 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  8. Cyberinfrastructure: The Second Revolution

    ERIC Educational Resources Information Center

    Bement, Arden L.

    2007-01-01

    The engine of change for the next revolution is cyberinfrastructure, a comprehensive phenomenon that involves the creation, dissemination, preservation, and application of knowledge. It adds new dimensions that greatly increase transformational potential. Cyberinfrastructure combines complex elements to create a dynamic system. It eclipses its…

  9. ACID FUNCTIONALIZED SINGLE-WALLED CARBON NANOTUBES ENHANCE CARDIAC ISCHEMIC/REPERFUSIOIN INJURY

    EPA Science Inventory

    Engineered carbon nanotubes are being intensively developed for wide applications. Because of their unique light properties, nanotubes can impose some potentially toxic effects, particularly if they have been modified to express functionally reactive chemical groups on their sur...

  10. WORKSHOP ON APPLICATION OF STATISTICAL METHODS TO BIOLOGICALLY-BASED PHARMACOKINETIC MODELING FOR RISK ASSESSMENT

    EPA Science Inventory

    Biologically-based pharmacokinetic models are being increasingly used in the risk assessment of environmental chemicals. These models are based on biological, mathematical, statistical and engineering principles. Their potential uses in risk assessment include extrapolation betwe...

  11. ACID-FUNCTIONALIZED SINGLE-WALLED CARBON NANOTUBES ENHANCE CARDIAC ISCHEMIC/REPERFUSION INJURY

    EPA Science Inventory

    Engineered nanotubes are being intensively developed for biomedical applications such as gene and drug delivery. Because of their unique properties, nanotubes can impose some potentially toxic effects, particularly if they have been modified to express functionally reactive chem...

  12. A comprehensive review of cryogels and their roles in tissue engineering applications.

    PubMed

    Hixon, Katherine R; Lu, Tracy; Sell, Scott A

    2017-10-15

    The extracellular matrix is fundamental in providing an appropriate environment for cell interaction and signaling to occur. Replicating such a matrix is advantageous in the support of tissue ingrowth and regeneration through the field of tissue engineering. While scaffolds can be fabricated in many ways, cryogels have recently become a popular approach due to their macroporous structure and durability. Produced through the crosslinking of gel precursors followed by a subsequent controlled freeze/thaw cycle, the resulting cryogel provides a unique, sponge-like structure. Therefore, cryogels have proven advantageous for many tissue engineering applications including roles in bioreactor systems, cell separation, and scaffolding. Specifically, the matrix has been demonstrated to encourage the production of various molecules, such as antibodies, and has also been used for cryopreservation. Cryogels can pose as a bioreactor for the expansion of cell lines, as well as a vehicle for cell separation. Lastly, this matrix has shown excellent potential as a tissue engineered scaffold, encouraging regrowth at numerous damaged tissue sites in vivo. This review will briefly discuss the fabrication of cryogels, with an emphasis placed on their application in various facets of tissue engineering to provide an overview of this unique scaffold's past and future roles. Cryogels are unique scaffolds produced through the controlled freezing and thawing of a polymer solution. There is an ever-growing body of literature that demonstrates their applicability in the realm of tissue engineering as extracellular matrix analogue scaffolds; with extensive information having been provided regarding the fabrication, porosity, and mechanical integrity of the scaffolds. Additionally, cryogels have been reviewed with respect to their role in bioseparation and as cellular incubators. This all-inclusive view of the roles that cryogels can play is critical to advancing the technology and expanding its niche within biomaterials and tissue engineering research. To the best of the authors' knowledge, this is the first comprehensive review of cryogel applications in tissue engineering that includes specific looks at their growing roles as extracellular matrix analogues, incubators, and in bioseparation processes. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  13. Applications of methylotrophs: can single carbon be harnessed for biotechnology?

    PubMed

    Chistoserdova, Ludmila

    2018-04-01

    This review summarizes developments in the field of applied research involving microbial conversion of single carbon compounds (methane, methanol, CO 2 ). The potential of the microorganisms involved in biotechnological applications could be realized via engineering native C1 utilizers toward higher output of value-added compounds, including biofuels, or via production of value chemicals as parts of novel, heterologously expressed biochemical pathways. Alternatively, C1 metabolism could be implemented in traditional industrial platforms (Escherichia coli, yeast), via introduction of specific metabolic modules. Most recent research spanning both approaches is covered. The potential of C1 utilizers in biomining of rare Earth elements, as well as the potential of C1 consuming microbial consortia in industrial applications are discussed. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. Lignocellulosic Biomass Derived Functional Materials: Synthesis and Applications in Biomedical Engineering.

    PubMed

    Zhang, Lei; Peng, Xinwen; Zhong, Linxin; Chua, Weitian; Xiang, Zhihua; Sun, Runcang

    2017-09-18

    The pertinent issue of resources shortage arising from global climate change in the recent years has accentuated the importance of materials that are environmental friendly. Despite the merits of current material like cellulose as the most abundant natural polysaccharide on earth, the incorporation of lignocellulosic biomass has the potential to value-add the recent development of cellulose-derivatives in drug delivery systems. Lignocellulosic biomass, with a hierarchical structure, comprised of cellulose, hemicellulose and lignin. As an excellent substrate that is renewable, biodegradable, biocompatible and chemically accessible for modified materials, lignocellulosic biomass sets forth a myriad of applications. To date, materials derived from lignocellulosic biomass have been extensively explored for new technological development and applications, such as biomedical, green electronics and energy products. In this review, chemical constituents of lignocellulosic biomass are first discussed before we critically examine the potential alternatives in the field of biomedical application. In addition, the pretreatment methods for extracting cellulose, hemicellulose and lignin from lignocellulosic biomass as well as their biological applications including drug delivery, biosensor, tissue engineering etc will be reviewed. It is anticipated there will be an increasing interest and research findings in cellulose, hemicellulose and lignin from natural resources, which help provide important directions for the development in biomedical applications. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. Development, modeling, simulation, and testing of a novel propane-fueled Brayton-Gluhareff cycle acoustically-pressurized ramjet engine

    NASA Astrophysics Data System (ADS)

    Bramlette, Richard B.

    In the 1950s, Eugene Gluhareff built the first working "pressure jet" engine, a variation on the classical ramjet engine with a pressurized inlet system relying on sonic tuning which allowed operation at subsonic speeds. The engine was an unqualified success. Unfortunately, after decades of sales and research, Gluhareff passed away leaving behind no significant published studies of the engine or detailed analysis of its operation. The design was at serious risk of being lost to history. This dissertation is intended to address that risk by studying a novel subscale modification of Gluhareff's original design operating on the same principles. Included is a background of related engine and how the pressure jet is distinct. The preliminary sizing of a pressure jet using closed-form expressions is then discussed followed by a review of propane oxidation modeling, how it integrates into the Computational Fluid Dynamics (CFD) solver, and the modeling of the pressure jet engine cycle with CFD. The simulation was matched to experimental data recorded on a purpose-built test stand recording chamber pressure, exhaust speed (via a Pitot/static system), temperatures, and thrust force. The engine CFD simulation produced a wide range of qualitative results that matched the experimental data well and suggested strong recirculation flows through the engine confirming suspicions about how the engine operates. Engine operating frequency between CFD and experiment also showed good agreement and appeared to be driven by the "Kadenacy Effect." The research effort lastly opens the door for further study of the engine cycle, the use of pressurized intakes to produce static thrust in a ramjet engine, the Gluhareff pressure jet's original geometry, and a wide array of potential applications. A roadmap of further study and applications is detailed including a modeling and testing of larger engines.

  16. Classical and Quantum Thermal Physics

    NASA Astrophysics Data System (ADS)

    Prasad, R.

    2016-11-01

    List of figures; List of tables; Preface; Acknowledgement; Dedication; 1. The kinetic theory of gases; 2. Ideal to real gas, viscosity, conductivity and diffusion; 3. Thermodynamics: definitions and Zeroth law; 4. First Law of Thermodynamics and some of its applications; 5. Second Law of Thermodynamics and some of its applications; 6. TdS equations and their applications; 7. Thermodynamic functions, potentials, Maxwell equations, the Third Law and equilibrium; 8. Some applications of thermodynamics to problems of physics and engineering; 9. Application of thermodynamics to chemical reactions; 10. Quantum thermodynamics; 11. Some applications of quantum thermodynamics; 12. Introduction to the thermodynamics of irreversible processes; Index.

  17. Additive Biotech-Chances, challenges, and recent applications of additive manufacturing technologies in biotechnology.

    PubMed

    Krujatz, Felix; Lode, Anja; Seidel, Julia; Bley, Thomas; Gelinsky, Michael; Steingroewer, Juliane

    2017-10-25

    The diversity and complexity of biotechnological applications are constantly increasing, with ever expanding ranges of production hosts, cultivation conditions and measurement tasks. Consequently, many analytical and cultivation systems for biotechnology and bioprocess engineering, such as microfluidic devices or bioreactors, are tailor-made to precisely satisfy the requirements of specific measurements or cultivation tasks. Additive manufacturing (AM) technologies offer the possibility of fabricating tailor-made 3D laboratory equipment directly from CAD designs with previously inaccessible levels of freedom in terms of structural complexity. This review discusses the historical background of these technologies, their most promising current implementations and the associated workflows, fabrication processes and material specifications, together with some of the major challenges associated with using AM in biotechnology/bioprocess engineering. To illustrate the great potential of AM, selected examples in microfluidic devices, 3D-bioprinting/biofabrication and bioprocess engineering are highlighted. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. 3D Printing of Cytocompatible Water-Based Light-Cured Polyurethane with Hyaluronic Acid for Cartilage Tissue Engineering Applications

    PubMed Central

    Shie, Ming-You; Chang, Wen-Ching; Wei, Li-Ju; Huang, Yu-Hsin; Chen, Chien-Han; Shih, Cheng-Ting; Chen, Yi-Wen; Shen, Yu-Fang

    2017-01-01

    Diseases in articular cartilages have affected millions of people globally. Although the biochemical and cellular composition of articular cartilages is relatively simple, there is a limitation in the self-repair ability of the cartilage. Therefore, developing strategies for cartilage repair is very important. Here, we report on a new liquid resin preparation process of water-based polyurethane based photosensitive materials with hyaluronic acid with application of the materials for 3D printed customized cartilage scaffolds. The scaffold has high cytocompatibility and is one that closely mimics the mechanical properties of articular cartilages. It is suitable for culturing human Wharton’s jelly mesenchymal stem cells (hWJMSCs) and the cells in this case showed an excellent chondrogenic differentiation capacity. We consider that the 3D printing hybrid scaffolds may have potential in customized tissue engineering and also facilitate the development of cartilage tissue engineering. PMID:28772498

  19. Shape Changing Airfoil

    NASA Technical Reports Server (NTRS)

    Ott, Eric A.

    2005-01-01

    Scoping of shape changing airfoil concepts including both aerodynamic analysis and materials-related technology assessment effort was performed. Three general categories of potential components were considered-fan blades, booster and compressor blades, and stator airfoils. Based on perceived contributions to improving engine efficiency, the fan blade was chosen as the primary application for a more detailed assessment. A high-level aerodynamic assessment using a GE90-90B Block 4 engine cycle and fan blade geometry indicates that blade camber changes of approximately +/-4deg would be sufficient to result in fan efficiency improvements nearing 1 percent. Constraints related to flight safety and failed mode operation suggest that use of the baseline blade shape with actuation to the optimum cruise condition during a portion of the cycle would be likely required. Application of these conditions to the QAT fan blade and engine cycle was estimated to result in an overall fan efficiency gain of 0.4 percent.

  20. Cooled variable nozzle radial turbine for rotor craft applications

    NASA Technical Reports Server (NTRS)

    Rogo, C.

    1981-01-01

    An advanced, small 2.27 kb/sec (5 lbs/sec), high temperature, variable area radial turbine was studied for a rotor craft application. Variable capacity cycles including single-shaft and free-turbine engine configurations were analyzed to define an optimum engine design configuration. Parametric optimizations were made on cooled and uncooled rotor configurations. A detailed structural and heat transfer analysis was conducted to provide a 4000-hour life HP turbine with material properties of the 1988 time frame. A pivoted vane and a moveable sidewall geometry were analyzed. Cooling and variable geometry penalties were included in the cycle analysis. A variable geometry free-turbine engine configuration with a design 1477K (2200 F) inlet temperature and a compressor pressure ratio of 16:1 was selected. An uncooled HP radial turbine rotor with a moveable sidewall nozzle showed the highest performance potential for a time weighted duty cycle.

  1. Engineering tissues, organs and cells.

    PubMed

    Atala, Anthony

    2007-01-01

    Patients suffering from diseased and injured organs may be treated with transplanted organs; however, there is a severe shortage of donor organs that is worsening yearly, given the ageing population. In the field of regenerative medicine and tissue engineering, scientists apply the principles of cell transplantation, materials science and bioengineering to construct biological substitutes that will restore and maintain normal function in diseased and injured tissues. Therapeutic cloning, where the nucleus from a donor cell is transferred into an enucleated oocyte in order to extract pluripotent embryonic stem cells, offers a potentially limitless source of cells for tissue engineering applications. The stem cell field is also advancing rapidly, opening new options for therapy, including the use of amniotic and placental fetal stem cells. This review covers recent advances that have occurred in regenerative medicine and describes applications of these technologies using chemical compounds that may offer novel therapies for patients with end-stage organ failure. 2007 John Wiley & Sons, Ltd

  2. Recent Applications of Coaxial and Emulsion Electrospinning Methods in the Field of Tissue Engineering

    PubMed Central

    McClellan, Phillip; Landis, William J.

    2016-01-01

    Abstract Electrospinning has emerged as an effective method of producing nanoscale fibers for use in multiple fields of study. One area of significant interest is nanofiber utilization for tissue engineering because the nanofibrous mats can mimic the native extracellular matrix of biological tissues. A logical next step is the inclusion of certain molecules and compounds to accelerate or increase the efficacy of tissue regeneration. Two methods are under scrutiny for their capability to encapsulate therapeutic compounds within electrospun nanofibers: emulsion and coaxial electrospinning. Both have advantages and disadvantages, which need to be taken into careful consideration when deciding to use them in a specific application. Several examples are provided here to highlight the vast potential of multilayered nanofibers as well as the emergence of new techniques to produce three-dimensional scaffolds of nanofibers for use in the field of tissue engineering. PMID:27610268

  3. Pulse Detonation Engines for High Speed Flight

    NASA Technical Reports Server (NTRS)

    Povinelli, Louis A.

    2002-01-01

    Revolutionary concepts in propulsion are required in order to achieve high-speed cruise capability in the atmosphere and for low cost reliable systems for earth to orbit missions. One of the advanced concepts under study is the air-breathing pulse detonation engine. Additional work remains in order to establish the role and performance of a PDE in flight applications, either as a stand-alone device or as part of a combined cycle system. In this paper, we shall offer a few remarks on some of these remaining issues, i.e., combined cycle systems, nozzles and exhaust systems and thrust per unit frontal area limitations. Currently, an intensive experimental and numerical effort is underway in order to quantify the propulsion performance characteristics of this device. In this paper, we shall highlight our recent efforts to elucidate the propulsion potential of pulse detonation engines and their possible application to high-speed or hypersonic systems.

  4. Energy-state formulation of lumped volume dynamic equations with application to a simplified free piston Stirling engine

    NASA Technical Reports Server (NTRS)

    Daniele, C. J.; Lorenzo, C. F.

    1979-01-01

    Lumped volume dynamic equations are derived using an energy state formulation. This technique requires that kinetic and potential energy state functions be written for the physical system being investigated. To account for losses in the system, a Rayleigh dissipation function is formed. Using these functions, a Lagrangian is formed and using Lagrange's equation, the equations of motion for the system are derived. The results of the application of this technique to a lumped volume are used to derive a model for the free piston Stirling engine. The model was simplified and programmed on an analog computer. Results are given comparing the model response with experimental data.

  5. Energy-state formulation of lumped volume dynamic equations with application to a simplified free piston Stirling engine

    NASA Technical Reports Server (NTRS)

    Daniele, C. J.; Lorenzo, C. F.

    1979-01-01

    Lumped volume dynamic equations are derived using an energy-state formulation. This technique requires that kinetic and potential energy state functions be written for the physical system being investigated. To account for losses in the system, a Rayleigh dissipation function is also formed. Using these functions, a Lagrangian is formed and using Lagrange's equation, the equations of motion for the system are derived. The results of the application of this technique to a lumped volume are used to derive a model for the free-piston Stirling engine. The model was simplified and programmed on an analog computer. Results are given comparing the model response with experimental data.

  6. The earth's surface studied from space; Proceedings of Workshop II of the COSPAR 25th Plenary Meeting, Graz, Austria, June 25-July 7, 1984

    NASA Technical Reports Server (NTRS)

    Ungar, S. G. (Editor)

    1985-01-01

    Consideration is given to: Landsat image data quality studies; a preliminary evaluation of Landsat-4 Thematic Mapper (TM) data for mineral exploration; and the early evaluation of TM data for mapping forest, agricultural and soil resources. Among other topics discussed are: shortwave infrared detection of vegetation; SPOT image quality and post-launch assessment; an evaluation of SPOT HRV simulation data for Corps of Engineers applications; and the application potential of SPOT imagery for topographic mapping. Consideration is also given to: verification studies of MOS-1 sensors; multiple sensor geocoded data; and the utility of proposed sensors for coastal engineering studies.

  7. Finding a roadmap to achieve large neuromorphic hardware systems

    PubMed Central

    Hasler, Jennifer; Marr, Bo

    2013-01-01

    Neuromorphic systems are gaining increasing importance in an era where CMOS digital computing techniques are reaching physical limits. These silicon systems mimic extremely energy efficient neural computing structures, potentially both for solving engineering applications as well as understanding neural computation. Toward this end, the authors provide a glimpse at what the technology evolution roadmap looks like for these systems so that Neuromorphic engineers may gain the same benefit of anticipation and foresight that IC designers gained from Moore's law many years ago. Scaling of energy efficiency, performance, and size will be discussed as well as how the implementation and application space of Neuromorphic systems are expected to evolve over time. PMID:24058330

  8. Challenges in Bio-fabrication of Organoid Cultures.

    PubMed

    Peng, Weijie; Datta, Pallab; Wu, Yang; Dey, Madhuri; Ayan, Bugra; Dababneh, Amer; Ozbolat, Ibrahim T

    2018-06-01

    Three-dimensional (3D) organoids have shown advantages in cell culture over traditional two-dimensional (2D) culture, and have great potential in various applications of tissue engineering. However, there are limitations in current organoid fabrication technologies, such as uncontrolled size, poor reproductively, and inadequate complexity of organoids. In this chapter, we present the existing techniques and discuss the major challenges for 3D organoid biofabrication. Future perspectives on organoid bioprinting are also discussed, where bioprinting technologies are expected to make a major contribution in organoid fabrication, such as realizing mass production and constructing complex heterotypic tissues, and thus further advance the translational application of organoids in tissue engineering and regenerative medicine as well drug testing and pharmaceutics.

  9. Biocompatibility of hydrogel-based scaffolds for tissue engineering applications.

    PubMed

    Naahidi, Sheva; Jafari, Mousa; Logan, Megan; Wang, Yujie; Yuan, Yongfang; Bae, Hojae; Dixon, Brian; Chen, P

    2017-09-01

    Recently, understanding of the extracellular matrix (ECM) has expanded rapidly due to the accessibility of cellular and molecular techniques and the growing potential and value for hydrogels in tissue engineering. The fabrication of hydrogel-based cellular scaffolds for the generation of bioengineered tissues has been based on knowledge of the composition and structure of ECM. Attempts at recreating ECM have used either naturally-derived ECM components or synthetic polymers with structural integrity derived from hydrogels. Due to their increasing use, their biocompatibility has been questioned since the use of these biomaterials needs to be effective and safe. It is not surprising then that the evaluation of biocompatibility of these types of biomaterials for regenerative and tissue engineering applications has been expanded from being primarily investigated in a laboratory setting to being applied in the multi-billion dollar medicinal industry. This review will aid in the improvement of design of non-invasive, smart hydrogels that can be utilized for tissue engineering and other biomedical applications. In this review, the biocompatibility of hydrogels and design criteria for fabricating effective scaffolds are examined. Examples of natural and synthetic hydrogels, their biocompatibility and use in tissue engineering are discussed. The merits and clinical complications of hydrogel scaffold use are also reviewed. The article concludes with a future outlook of the field of biocompatibility within the context of hydrogel-based scaffolds. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. 40 CFR 1068.31 - What provisions apply to nonroad or stationary engines that change their status?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... nonroad application is subsequently used in an application other than a nonroad application, or when an engine previously used in a stationary application (i.e., an engine that was not used as a nonroad engine... stationary engine becomes a new nonroad engine if— (1) It is used in an application that meets the criteria...

  11. The History and Promise of Combined Cycle Engines for Access to Space Applications

    NASA Technical Reports Server (NTRS)

    Clark, Casie

    2010-01-01

    For the summer of 2010, I have been working in the Aerodynamics and Propulsion Branch at NASA Dryden Flight Research Center studying combined-cycle engines, a high speed propulsion concept. Combined cycle engines integrate multiple propulsion systems into a single engine capable of running in multiple modes. These different modes allow the engine to be extremely versatile and efficient in varied flight conditions. The two most common types of combined cycle engines are Rocket-Based Combined Cycle (RBCC) and Turbine Based Combined Cycle (TBCC). The RBCC essentially combines a rocket and ramjet engine, while the TBCC integrates a turbojet and ramjet1. These two engines are able to switch between different propulsion modes to achieve maximum performance. Extensive conceptual and ground test studies of RBCC engines have been undertaken; however, an RBCC engine has never, to my knowledge, been demonstrated in flight. RBCC engines are of particular interest because they could potentially power a reusable launch vehicle (RLV) into space. The TBCC has been flight tested and shown to be effective at reaching supersonic speeds, most notably in the SR-71 Blackbird2.

  12. Oligoaniline-based conductive biomaterials for tissue engineering.

    PubMed

    Zarrintaj, Payam; Bakhshandeh, Behnaz; Saeb, Mohammad Reza; Sefat, Farshid; Rezaeian, Iraj; Ganjali, Mohammad Reza; Ramakrishna, Seeram; Mozafari, Masoud

    2018-05-01

    The science and engineering of biomaterials have improved the human life expectancy. Tissue engineering is one of the nascent strategies with an aim to fulfill this target. Tissue engineering scaffolds are one of the most significant aspects of the recent tissue repair strategies; hence, it is imperative to design biomimetic substrates with suitable features. Conductive substrates can ameliorate the cellular activity through enhancement of cellular signaling. Biocompatible polymers with conductivity can mimic the cells' niche in an appropriate manner. Bioconductive polymers based on aniline oligomers can potentially actualize this purpose because of their unique and tailoring properties. The aniline oligomers can be positioned within the molecular structure of other polymers, thus painter acting with the side groups of the main polymer or acting as a comonomer in their backbone. The conductivity of oligoaniline-based conductive biomaterials can be tailored to mimic the electrical and mechanical properties of targeted tissues/organs. These bioconductive substrates can be designed with high mechanical strength for hard tissues such as the bone and with high elasticity to be used for the cardiac tissue or can be synthesized in the form of injectable hydrogels, particles, and nanofibers for noninvasive implantation; these structures can be used for applications such as drug/gene delivery and extracellular biomimetic structures. It is expected that with progress in the fields of biomaterials and tissue engineering, more innovative constructs will be proposed in the near future. This review discusses the recent advancements in the use of oligoaniline-based conductive biomaterials for tissue engineering and regenerative medicine applications. The tissue engineering applications of aniline oligomers and their derivatives have recently attracted an increasing interest due to their electroactive and biodegradable properties. However, no reports have systematically reviewed the critical role of oligoaniline-based conductive biomaterials in tissue engineering. Research on aniline oligomers is growing today opening new scenarios that expand the potential of these biomaterials from "traditional" treatments to a new era of tissue engineering. The conductivity of this class of biomaterials can be tailored similar to that of tissues/organs. To the best of our knowledge, this is the first review article in which such issue is systematically reviewed and critically discussed in the light of the existing literature. Undoubtedly, investigations on the use of oligoaniline-based conductive biomaterials in tissue engineering need further advancement and a lot of critical questions are yet to be answered. In this review, we introduce the salient features, the hurdles that must be overcome, the hopes, and practical constraints for further development. Copyright © 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  13. Transferable and flexible thin film devices for engineering applications

    NASA Astrophysics Data System (ADS)

    Mutyala, Madhu Santosh K.; Zhou, Jingzhou; Li, Xiaochun

    2014-05-01

    Thin film devices can be of significance for manufacturing, energy conversion systems, solid state electronics, wireless applications, etc. However, these thin film sensors/devices are normally fabricated on rigid silicon substrates, thus neither flexible nor transferrable for engineering applications. This paper reports an innovative approach to transfer polyimide (PI) embedded thin film devices, which were fabricated on glass, to thin metal foils. Thin film thermocouples (TFTCs) were fabricated on a thin PI film, which was spin coated and cured on a glass substrate. Another layer of PI film was then spin coated again on TFTC/PI and cured to obtain the embedded TFTCs. Assisted by oxygen plasma surface coarsening of the PI film on the glass substrate, the PI embedded TFTC was successfully transferred from the glass substrate to a flexible copper foil. To demonstrate the functionality of the flexible embedded thin film sensors, they were transferred to the sonotrode tip of an ultrasonic metal welding machine for in situ process monitoring. The dynamic temperatures near the sonotrode tip were effectively measured under various ultrasonic vibration amplitudes. This technique of transferring polymer embedded electronic devices onto metal foils yield great potentials for numerous engineering applications.

  14. Reduced graphene oxide-coated hydroxyapatite composites stimulate spontaneous osteogenic differentiation of human mesenchymal stem cells

    NASA Astrophysics Data System (ADS)

    Lee, Jong Ho; Shin, Yong Cheol; Jin, Oh Seong; Kang, Seok Hee; Hwang, Yu-Shik; Park, Jong-Chul; Hong, Suck Won; Han, Dong-Wook

    2015-07-01

    Human mesenchymal stem cells (hMSCs) have great potential as cell sources for bone tissue engineering and regeneration, but the control and induction of their specific differentiation into bone cells remain challenging. Graphene-based nanomaterials are considered attractive candidates for biomedical applications such as scaffolds in tissue engineering, substrates for SC differentiation and components of implantable devices, due to their biocompatible and bioactive properties. Despite the potential biomedical applications of graphene and its derivatives, only limited information is available regarding their osteogenic activity. This study concentrates upon the effects of reduced graphene oxide (rGO)-coated hydroxyapatite (HAp) composites on osteogenic differentiation of hMSCs. The average particle sizes of HAp and rGO were 1270 +/- 476 nm and 438 +/- 180 nm, respectively. When coated on HAp particulates, rGO synergistically enhanced spontaneous osteogenic differentiation of hMSCs, without hampering their proliferation. This result was confirmed by determining alkaline phosphatase activity and mineralization of calcium and phosphate as early and late stage markers of osteogenic differentiation. It is suggested that rGO-coated HAp composites can be effectively utilized as dental and orthopedic bone fillers since these graphene-based particulate materials have potent effects on stimulating the spontaneous differentiation of MSCs and show superior bioactivity and osteoinductive potential.Human mesenchymal stem cells (hMSCs) have great potential as cell sources for bone tissue engineering and regeneration, but the control and induction of their specific differentiation into bone cells remain challenging. Graphene-based nanomaterials are considered attractive candidates for biomedical applications such as scaffolds in tissue engineering, substrates for SC differentiation and components of implantable devices, due to their biocompatible and bioactive properties. Despite the potential biomedical applications of graphene and its derivatives, only limited information is available regarding their osteogenic activity. This study concentrates upon the effects of reduced graphene oxide (rGO)-coated hydroxyapatite (HAp) composites on osteogenic differentiation of hMSCs. The average particle sizes of HAp and rGO were 1270 +/- 476 nm and 438 +/- 180 nm, respectively. When coated on HAp particulates, rGO synergistically enhanced spontaneous osteogenic differentiation of hMSCs, without hampering their proliferation. This result was confirmed by determining alkaline phosphatase activity and mineralization of calcium and phosphate as early and late stage markers of osteogenic differentiation. It is suggested that rGO-coated HAp composites can be effectively utilized as dental and orthopedic bone fillers since these graphene-based particulate materials have potent effects on stimulating the spontaneous differentiation of MSCs and show superior bioactivity and osteoinductive potential. Electronic supplementary information (ESI) available: Additional figures. See DOI: 10.1039/c5nr01580d

  15. Quantitative Tracking of Combinatorially Engineered Populations with Multiplexed Binary Assemblies.

    PubMed

    Zeitoun, Ramsey I; Pines, Gur; Grau, Willliam C; Gill, Ryan T

    2017-04-21

    Advances in synthetic biology and genomics have enabled full-scale genome engineering efforts on laboratory time scales. However, the absence of sufficient approaches for mapping engineered genomes at system-wide scales onto performance has limited the adoption of more sophisticated algorithms for engineering complex biological systems. Here we report on the development and application of a robust approach to quantitatively map combinatorially engineered populations at scales up to several dozen target sites. This approach works by assembling genome engineered sites with cell-specific barcodes into a format compatible with high-throughput sequencing technologies. This approach, called barcoded-TRACE (bTRACE) was applied to assess E. coli populations engineered by recursive multiplex recombineering across both 6-target sites and 31-target sites. The 31-target library was then tracked throughout growth selections in the presence and absence of isopentenol (a potential next-generation biofuel). We also use the resolution of bTRACE to compare the influence of technical and biological noise on genome engineering efforts.

  16. Summary of Results from Space Shuttle Main Engine Off-Nominal Testing

    NASA Technical Reports Server (NTRS)

    Horton, James F.; Megivern, Jeffrey M.; McNutt, Leslie M.

    2011-01-01

    This paper is a summary of Space Shuttle Main Engine (SSME) off-nominal testing that occurred during 2008 and 2009. During the last two years of planned SSME testing at Stennis Space Center, Pratt & Whitney Rocketdyne worked with their NASA MSFC customer to systematically identify, develop, assess, and implement challenging test objectives in order to expand the knowledge of one of the world s most reliable and highly tested large rocket engine. The objectives successfully investigated three main areas of interest expanding engine performance margins, demonstrating system operational capabilities, and establishing ground work for new rocket engine technology. The testing gave the Space Shuttle Program new options to safely fly out the flight manifest and provided Pratt & Whitney Rocketdyne and NASA new insight into the operational capabilities of the SSME, capabilities which can be used in assessing potential future applications of the RS-25 engine.

  17. Pneumatic injection system using a hot exhaust gases, developed in Institute of Automobiles and Internal Combustion Engines of Cracow University of Technology

    NASA Astrophysics Data System (ADS)

    Marek, W.; Śliwiński, K.

    2016-09-01

    The article concerns research carried out by the Krakow University of Technology on the concept of a pneumatic fuel injection spark ignition engines. In this artkule an example of an application of this type of power to the Wankel's engine, together with a description of its design and operating principles and the benefits of its use. The work was carried out over many years by Prof. Stanislaw Jarnuszkiewicz despite the development of many patents but not widely used in engines. Authors who were involved in the team-work of the team of Prof. Jarnuszkiewicz, after conducting exploratory studies, believed that this solution has development potential and this will be presented in future articles.

  18. Steam engine research for solar parabolic dish

    NASA Technical Reports Server (NTRS)

    Demler, R. L.

    1981-01-01

    The parabolic dish solar concentrator provides an opportunity to generate high grade energy in a modular system. Most of the capital is projected to be in the dish and its installation. Assurance of a high production demand of a standard dish could lead to dramatic cost reductions. High production volume in turn depends upon maximum application flexibility by providing energy output options, e.g., heat, electricity, chemicals and combinations thereof. Subsets of these options include energy storage and combustion assist. A steam engine design and experimental program is described which investigate the efficiency potential of a small 25 kW compound reheat cycle piston engine. An engine efficiency of 35 percent is estimated for a 700 C steam temperature from the solar receiver.

  19. The potential impact of bone tissue engineering in the clinic

    PubMed Central

    Mishra, Ruchi; Bishop, Tyler; Valerio, Ian L; Fisher, John P; Dean, David

    2016-01-01

    Bone tissue engineering (BTE) intends to restore structural support for movement and mineral homeostasis, and assist in hematopoiesis and the protective functions of bone in traumatic, degenerative, cancer, or congenital malformation. While much effort has been put into BTE, very little of this research has been translated to the clinic. In this review, we discuss current regenerative medicine and restorative strategies that utilize tissue engineering approaches to address bone defects within a clinical setting. These approaches involve the primary components of tissue engineering: cells, growth factors and biomaterials discussed briefly in light of their clinical relevance. This review also presents upcoming advanced approaches for BTE applications and suggests a probable workpath for translation from the laboratory to the clinic. PMID:27549369

  20. Molecular Bases of cyclodextrin Adapter Interactions with Engineered Protein Nanopores

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Banerjee, A.; Mikhailova, E; Cheley, S

    2010-01-01

    Engineered protein pores have several potential applications in biotechnology: as sensor elements in stochastic detection and ultrarapid DNA sequencing, as nanoreactors to observe single-molecule chemistry, and in the construction of nano- and micro-devices. One important class of pores contains molecular adapters, which provide internal binding sites for small molecules. Mutants of the {alpha}-hemolysin ({alpha}HL) pore that bind the adapter {beta}-cyclodextrin ({beta}CD) {approx}10{sup 4} times more tightly than the wild type have been obtained. We now use single-channel electrical recording, protein engineering including unnatural amino acid mutagenesis, and high-resolution x-ray crystallography to provide definitive structural information on these engineered protein nanoporesmore » in unparalleled detail.« less

  1. Sustainable stabilization of sulfate-bearing soils with expansive soil-rubber technology.

    DOT National Transportation Integrated Search

    2013-03-01

    The beneficial use of scrap tire rubber mixed with expansive soils is of interest to civil engineering : applications since the swell percent and the swell pressure can be potentially reduced with no deleterious : effect to the shear strength of the ...

  2. Nanotechnology and stem cell therapy for cardiovascular diseases: potential applications.

    PubMed

    La Francesca, Saverio

    2012-01-01

    The use of stem cell therapy for the treatment of cardiovascular diseases has generated significant interest in recent years. Limitations to the clinical application of this therapy center on issues of stem cell delivery, engraftment, and fate. Nanotechnology-based cell labeling and imaging techniques facilitate stem cell tracking and engraftment studies. Nanotechnology also brings exciting new opportunities to translational stem cell research as it enables the controlled engineering of nanoparticles and nanomaterials that can properly relate to the physical scale of cell-cell and cell-niche interactions. This review summarizes the most relevant potential applications of nanoscale technologies to the field of stem cell therapy for the treatment of cardiovascular diseases.

  3. USAF solar thermal applications case studies

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The potential of solar energy technologies to meet mission related applications for process heat was investigated. The reduction of the dependence of military installations on fossil fuels by promoting the use of more abundant resources where liquid hydrocarbons and natural gas are now used is examined. The evaluation and utilization of renewable energy systems to provide process heat and space heating are emphasized. The application of thermal energy systems is divided into four steps: (1) investigation of the potential operational cost effectiveness of selected thermal technologies; (2) selection of a site and preliminary design of point focussing solar thermal plant; (3) construction and test of an engineering prototype; and (4) installation and operation of a solar thermal energy plant.

  4. Carbon dots: emerging theranostic nanoarchitectures.

    PubMed

    Mishra, Vijay; Patil, Akshay; Thakur, Sourav; Kesharwani, Prashant

    2018-06-01

    Nanotechnology has gained significant interest from biomedical and analytical researchers in recent years. Carbon dots (C-dots), a new member of the carbon nanomaterial family, are spherical, nontoxic, biocompatible, and discrete particles less than 10nm in diameter. Research interest has focused on C-dots because of their ultra-compact nanosize, favorable biocompatibility, outstanding photoluminescence, superior electron transfer ability, and versatile surface engineering properties. C-dots show significant potential for use in cellular imaging, biosensing, targeted drug delivery, and other biomedical applications. Here we discuss C-dots, in terms of their physicochemical properties, fabrication techniques, toxicity issues, surface engineering and biomedical potential in drug delivery, targeting as well as bioimaging. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Coannular plug nozzle noise reduction and impact of exhaust system designs

    NASA Technical Reports Server (NTRS)

    Lee, R.

    1976-01-01

    Reducing the noise generated by high velocity jets has confronted engine designers and acoustics workers alike for the past fifteen years. Some of the jet noise suppressor configurations that are investigated are shown. With the exception of the early CJ-805 daisy suppressor nozzle which found successful application on the Convair 990 airplane, the others were developmental hardware at different stages of the effort in the past eight years - all aiming at potential supersonic cruise aircraft applications. Some significant progress was made as the result of work supported by NASA and FAA in the past two to three years. This work pertains to the concept demonstration and scale model testing of coannular plug nozzles with inverted velocity profile, and to the preliminary study of its application to advanced variable cycle engines (VCE) appropriate for supersonic cruise aircraft.

  6. Application of theoretical methods to increase succinate production in engineered strains.

    PubMed

    Valderrama-Gomez, M A; Kreitmayer, D; Wolf, S; Marin-Sanguino, A; Kremling, A

    2017-04-01

    Computational methods have enabled the discovery of non-intuitive strategies to enhance the production of a variety of target molecules. In the case of succinate production, reviews covering the topic have not yet analyzed the impact and future potential that such methods may have. In this work, we review the application of computational methods to the production of succinic acid. We found that while a total of 26 theoretical studies were published between 2002 and 2016, only 10 studies reported the successful experimental implementation of any kind of theoretical knowledge. None of the experimental studies reported an exact application of the computational predictions. However, the combination of computational analysis with complementary strategies, such as directed evolution and comparative genome analysis, serves as a proof of concept and demonstrates that successful metabolic engineering can be guided by rational computational methods.

  7. Molecular Strategies for Morphology Control in Semiconducting Polymers for Optoelectronics.

    PubMed

    Rahmanudin, Aiman; Sivula, Kevin

    2017-06-28

    Solution-processable semiconducting polymers have been explored over the last decades for their potential applications in inexpensively fabricated transistors, diodes and photovoltaic cells. However, a remaining challenge in the field is to control the solid-state self-assembly of polymer chains in thin films devices, as the aspects of (semi)crystallinity, grain boundaries, and chain entanglement can drastically affect intra-and inter-molecular charge transport/transfer and thus device performance. In this short review we examine how the aspects of molecular weight and chain rigidity affect solid-state self-assembly and highlight molecular engineering strategies to tune thin film morphology. Side chain engineering, flexibly linking conjugation segments, and block co-polymer strategies are specifically discussed with respect to their effect on field effect charge carrier mobility in transistors and power conversion efficiency in solar cells. Example systems are taken from recent literature including work from our laboratories to illustrate the potential of molecular engineering semiconducting polymers.

  8. Technology requirements for advanced earth-orbital transportation systems, dual-mode propulsion

    NASA Technical Reports Server (NTRS)

    Haefeli, R. C.; Littler, E. G.; Hurley, J. B.; Winter, M. G.

    1977-01-01

    The application of dual-mode propulsion concepts to fully reusable single-stage-to-orbit (SSTO) vehicles is discussed. Dual-mode propulsion uses main rocket engines that consume hydrocarbon fuels as well as liquid hydrogen fuel. Liquid oxygen is used as the oxidizer. These engine concepts were integrated into transportation vehicle designs capable of vertical takeoff, delivering a payload to earth orbit, and return to earth with a horizontal landing. Benefits of these vehicles were assessed and compared with vehicles using single-mode propulsion (liquid hydrogen and oxygen engines). Technology requirements for such advanced transportation systems were identified. Figures of merit, including life-cycle cost savings and research costs, were derived for dual-mode technology programs, and were used for assessments of potential benefits of proposed technology activities. Dual-mode propulsion concepts display potential for significant cost and performance benefits when applied to SSTO vehicles.

  9. Defect-Engineered Metal–Organic Frameworks

    PubMed Central

    Fang, Zhenlan; Bueken, Bart; De Vos, Dirk E; Fischer, Roland A

    2015-01-01

    Defect engineering in metal–organic frameworks (MOFs) is an exciting concept for tailoring material properties, which opens up novel opportunities not only in sorption and catalysis, but also in controlling more challenging physical characteristics such as band gap as well as magnetic and electrical/conductive properties. It is challenging to structurally characterize the inherent or intentionally created defects of various types, and there have so far been few efforts to comprehensively discuss these issues. Based on selected reports spanning the last decades, this Review closes that gap by providing both a concise overview of defects in MOFs, or more broadly coordination network compounds (CNCs), including their classification and characterization, together with the (potential) applications of defective CNCs/MOFs. Moreover, we will highlight important aspects of “defect-engineering” concepts applied for CNCs, also in comparison with relevant solid materials such as zeolites or COFs. Finally, we discuss the future potential of defect-engineered CNCs. PMID:26036179

  10. Suitability of a PLCL fibrous scaffold for soft tissue engineering applications: A combined biological and mechanical characterisation.

    PubMed

    Laurent, Cédric P; Vaquette, Cédryck; Liu, Xing; Schmitt, Jean-François; Rahouadj, Rachid

    2018-04-01

    Poly(lactide-co-ε-caprolactone) (PLCL) has been reported to be a good candidate for tissue engineering because of its good biocompatibility. Particularly, a braided PLCL scaffold (PLL/PCL ratio = 85/15) has been recently designed and partially validated for ligament tissue engineering. In the present study, we assessed the in vivo biocompatibility of acellular and cellularised scaffolds in a rat model. We then determined its in vitro biocompatibility using stem cells issued from both bone marrow and Wharton Jelly. From a biological point of view, the scaffold was shown to be suitable for tissue engineering in all these cases. Secondly, while the initial mechanical properties of this scaffold have been previously reported to be adapted to load-bearing applications, we studied the evolution in time of the mechanical properties of PLCL fibres due to hydrolytic degradation. Results for isolated PLCL fibres were extrapolated to the fibrous scaffold using a previously developed numerical model. It was shown that no accumulation of plastic strain was to be expected for a load-bearing application such as anterior cruciate ligament tissue engineering. However, PLCL fibres exhibited a non-expected brittle behaviour after two months. This may involve a potential risk of premature failure of the scaffold, unless tissue growth compensates this change in mechanical properties. This combined study emphasises the need to characterise the properties of biomaterials in a pluridisciplinary approach, since biological and mechanical characterisations led in this case to different conclusions concerning the suitability of this scaffold for load-bearing applications.

  11. Preparation of Laponite Bioceramics for Potential Bone Tissue Engineering Applications

    PubMed Central

    Li, Kai; Ju, Yaping; Li, Jipeng; Zhang, Yongxing; Li, Jinhua; Liu, Xuanyong; Shi, Xiangyang; Zhao, Qinghua

    2014-01-01

    We report a facile approach to preparing laponite (LAP) bioceramics via sintering LAP powder compacts for bone tissue engineering applications. The sintering behavior and mechanical properties of LAP compacts under different temperatures, heating rates, and soaking times were investigated. We show that LAP bioceramic with a smooth and porous surface can be formed at 800°C with a heating rate of 5°C/h for 6 h under air. The formed LAP bioceramic was systematically characterized via different methods. Our results reveal that the LAP bioceramic possesses an excellent surface hydrophilicity and serum absorption capacity, and good cytocompatibility and hemocompatibility as demonstrated by resazurin reduction assay of rat mesenchymal stem cells (rMSCs) and hemolytic assay of pig red blood cells, respectively. The potential bone tissue engineering applicability of LAP bioceramic was explored by studying the surface mineralization behavior via soaking in simulated body fluid (SBF), as well as the surface cellular response of rMSCs. Our results suggest that LAP bioceramic is able to induce hydroxyapatite deposition on its surface when soaked in SBF and rMSCs can proliferate well on the LAP bioceramic surface. Most strikingly, alkaline phosphatase activity together with alizarin red staining results reveal that the produced LAP bioceramic is able to induce osteoblast differentiation of rMSCs in growth medium without any inducing factors. Finally, in vivo animal implantation, acute systemic toxicity test and hematoxylin and eosin (H&E)-staining data demonstrate that the prepared LAP bioceramic displays an excellent biosafety and is able to heal the bone defect. Findings from this study suggest that the developed LAP bioceramic holds a great promise for treating bone defects in bone tissue engineering. PMID:24955961

  12. Rational Modular RNA Engineering Based on In Vivo Profiling of Structural Accessibility.

    PubMed

    Leistra, Abigail N; Amador, Paul; Buvanendiran, Aishwarya; Moon-Walker, Alex; Contreras, Lydia M

    2017-12-15

    Bacterial small RNAs (sRNAs) have been established as powerful parts for controlling gene expression. However, development and application of engineered sRNAs has primarily focused on regulating novel synthetic targets. In this work, we demonstrate a rational modular RNA engineering approach that uses in vivo structural accessibility measurements to tune the regulatory activity of a multisubstrate sRNA for differential control of its native target network. Employing the CsrB global sRNA regulator as a model system, we use published in vivo structural accessibility data to infer the contribution of its local structures (substructures) to function and select a subset for engineering. We then modularly recombine the selected substructures, differentially representing those of presumed high or low functional contribution, to build a library of 21 CsrB variants. Using fluorescent translational reporter assays, we demonstrate that the CsrB variants achieve a 5-fold gradient of control of well-characterized Csr network targets. Interestingly, results suggest that less conserved local structures within long, multisubstrate sRNAs may represent better targets for rational engineering than their well-conserved counterparts. Lastly, mapping the impact of sRNA variants on a signature Csr network phenotype indicates the potential of this approach for tuning the activity of global sRNA regulators in the context of metabolic engineering applications.

  13. Engineering the biosynthesis of novel rhamnolipids in Escherichia coli for enhanced oil recovery.

    PubMed

    Han, L; Liu, P; Peng, Y; Lin, J; Wang, Q; Ma, Y

    2014-07-01

    The interfacial tension of rhamnolipids and their applications in enhanced oil recovery are dependent on their chemical structures and compositions. To improve their performances of interfacial tension and enhanced oil recovery, the engineered strategies were applied to produce novel rhamnolipids with different chemical structures and compositions. By introducing different key genes for rhamnolipid biosynthesis, Escherichia coli was firstly constructed to produce rhamnolipids that showed different performances in interfacial tension from those from Pseudomonas aeruginosa due to the different fatty acyl compositions. Then, the mutant RhlBs were created by directed evolution and subsequent site-directed mutagenesis and resulted in the production of the novel rhamnolipids with the different performances in interfacial tension as well as enhanced oil recovery. Lastly, computational modelling elucidates that the single amino acid mutation at the position 168 in RhlB would change the volume of binding pocket for substrate and thus affect the selectivity of rhamnolipid formation in E. coli. The novel rhamnolipids that showed the improved performances of interfacial tension and the potential different applications in enhanced oil recovery were successfully produced by engineered E. coli. This study proved that the combination of metabolic engineering and protein engineering is an important engineered strategy to produce many novel metabolites in micro-organisms. © 2014 The Society for Applied Microbiology.

  14. Cell–scaffold interaction within engineered tissue

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Haiping; Liu, Yuanyuan, E-mail: Yuanyuan_liu@shu.edu.cn; Jiang, Zhenglong

    The structure of a tissue engineering scaffold plays an important role in modulating tissue growth. A novel gelatin–chitosan (Gel–Cs) scaffold with a unique structure produced by three-dimensional printing (3DP) technology combining with vacuum freeze-drying has been developed for tissue-engineering applications. The scaffold composed of overall construction, micro-pore, surface morphology, and effective mechanical property. Such a structure meets the essential design criteria of an ideal engineered scaffold. The favorable cell–matrix interaction supports the active biocompatibility of the structure. The structure is capable of supporting cell attachment and proliferation. Cells seeded into this structure tend to maintain phenotypic shape and secreted largemore » amounts of extracellular matrix (ECM) and the cell growth decreased the mechanical properties of scaffold. This novel biodegradable scaffold has potential applications for tissue engineering based upon its unique structure, which acts to support cell growth. - Highlights: • The scaffold is not only for providing a surface for cell residence but also for determining cell phenotype and retaining structural integrity. • The mechanical property of scaffold can be affected by activities of cell. • The scaffold provides a microenvironment for cell attachment, growth, and migration.« less

  15. HPC in a HEP lab: lessons learned from setting up cost-effective HPC clusters

    NASA Astrophysics Data System (ADS)

    Husejko, Michal; Agtzidis, Ioannis; Baehler, Pierre; Dul, Tadeusz; Evans, John; Himyr, Nils; Meinhard, Helge

    2015-12-01

    In this paper we present our findings gathered during the evaluation and testing of Windows Server High-Performance Computing (Windows HPC) in view of potentially using it as a production HPC system for engineering applications. The Windows HPC package, an extension of Microsofts Windows Server product, provides all essential interfaces, utilities and management functionality for creating, operating and monitoring a Windows-based HPC cluster infrastructure. The evaluation and test phase was focused on verifying the functionalities of Windows HPC, its performance, support of commercial tools and the integration with the users work environment. We describe constraints imposed by the way the CERN Data Centre is operated, licensing for engineering tools and scalability and behaviour of the HPC engineering applications used at CERN. We will present an initial set of requirements, which were created based on the above constraints and requests from the CERN engineering user community. We will explain how we have configured Windows HPC clusters to provide job scheduling functionalities required to support the CERN engineering user community, quality of service, user- and project-based priorities, and fair access to limited resources. Finally, we will present several performance tests we carried out to verify Windows HPC performance and scalability.

  16. Quantum optomechanical piston engines powered by heat

    NASA Astrophysics Data System (ADS)

    Mari, A.; Farace, A.; Giovannetti, V.

    2015-09-01

    We study two different models of optomechanical systems where a temperature gradient between two radiation baths is exploited for inducing self-sustained coherent oscillations of a mechanical resonator. From a thermodynamic perspective, such systems represent quantum instances of self-contained thermal machines converting heat into a periodic mechanical motion and thus they can be interpreted as nano-scale analogues of macroscopic piston engines. Our models are potentially suitable for testing fundamental aspects of quantum thermodynamics in the laboratory and for applications in energy efficient nanotechnology.

  17. Porous Shape Memory Polymers

    PubMed Central

    Hearon, Keith; Singhal, Pooja; Horn, John; Small, Ward; Olsovsky, Cory; Maitland, Kristen C.; Wilson, Thomas S.; Maitland, Duncan J.

    2013-01-01

    Porous shape memory polymers (SMPs) include foams, scaffolds, meshes, and other polymeric substrates that possess porous three-dimensional macrostructures. Porous SMPs exhibit active structural and volumetric transformations and have driven investigations in fields ranging from biomedical engineering to aerospace engineering to the clothing industry. The present review article examines recent developments in porous SMPs, with focus given to structural and chemical classification, methods of characterization, and applications. We conclude that the current body of literature presents porous SMPs as highly interesting smart materials with potential for industrial use. PMID:23646038

  18. Photovoltaic power system reliability considerations

    NASA Technical Reports Server (NTRS)

    Lalli, V. R.

    1980-01-01

    An example of how modern engineering and safety techniques can be used to assure the reliable and safe operation of photovoltaic power systems is presented. This particular application is for a solar cell power system demonstration project designed to provide electric power requirements for remote villages. The techniques utilized involve a definition of the power system natural and operating environment, use of design criteria and analysis techniques, an awareness of potential problems via the inherent reliability and FMEA methods, and use of fail-safe and planned spare parts engineering philosophy.

  19. Application of Additively Manufactured Components in Rocket Engine Turbopumps

    NASA Technical Reports Server (NTRS)

    Calvert, Marty, Jr.; Hanks, Andrew; Schmauch, Preston; Delessio, Steve

    2015-01-01

    The use of additive manufacturing technology has the potential to revolutionize the development of turbopump components in liquid rocket engines. When designing turbomachinery with the additive process there are several benefits and risks that are leveraged relative to a traditional development cycle. This topic explores the details and development of a 90,000 RPM Liquid Hydrogen Turbopump from which 90% of the parts were derived from the additive process. This turbopump was designed, developed and will be tested later this year at Marshall Space Flight Center.

  20. Photovoltaic power system reliability considerations

    NASA Technical Reports Server (NTRS)

    Lalli, V. R.

    1980-01-01

    This paper describes an example of how modern engineering and safety techniques can be used to assure the reliable and safe operation of photovoltaic power systems. This particular application was for a solar cell power system demonstration project in Tangaye, Upper Volta, Africa. The techniques involve a definition of the power system natural and operating environment, use of design criteria and analysis techniques, an awareness of potential problems via the inherent reliability and FMEA methods, and use of a fail-safe and planned spare parts engineering philosophy.

  1. 46 CFR 13.501 - Original application for tankerman-engineer endorsement.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Original application for tankerman-engineer endorsement... AND SEAMEN CERTIFICATION OF TANKERMEN Requirements for Tankerman-Engineer Endorsement § 13.501 Original application for tankerman-engineer endorsement. Each applicant for a tankerman-engineer...

  2. Microbial Consortia Engineering for Cellular Factories: in vitro to in silico systems

    PubMed Central

    Bernstein, Hans C; Carlson, Ross P

    2012-01-01

    This mini-review discusses the current state of experimental and computational microbial consortia engineering with a focus on cellular factories. A discussion of promising ecological theories central to community resource usage is presented to facilitate interpretation of consortial designs. Recent case studies exemplifying different resource usage motifs and consortial assembly templates are presented. The review also highlights in silico approaches to design and to analyze consortia with an emphasis on stoichiometric modeling methods. The discipline of microbial consortia engineering possesses a widely accepted potential to generate highly novel and effective bio-catalysts for applications from biofuels to specialty chemicals to enhanced mineral recovery. PMID:24688677

  3. Adult mesenchymal stem cells and cell-based tissue engineering

    PubMed Central

    Tuan, Rocky S; Boland, Genevieve; Tuli, Richard

    2003-01-01

    The identification of multipotential mesenchymal stem cells (MSCs) derived from adult human tissues, including bone marrow stroma and a number of connective tissues, has provided exciting prospects for cell-based tissue engineering and regeneration. This review focuses on the biology of MSCs, including their differentiation potentials in vitro and in vivo, and the application of MSCs in tissue engineering. Our current understanding of MSCs lags behind that of other stem cell types, such as hematopoietic stem cells. Future research should aim to define the cellular and molecular fingerprints of MSCs and elucidate their endogenous role(s) in normal and abnormal tissue functions. PMID:12716446

  4. Lean Stability augmentation study

    NASA Technical Reports Server (NTRS)

    Mcvey, J. B.; Kennedy, J. B.

    1979-01-01

    An analytical and experimental program was conducted to investigate techniques and develop technology for improving the lean combustion limits of premixing, prevaporizing combustors applicable to gas turbine engine main burners. Three concepts for improving lean stability limits were selected for experimental evaluation among twelve approaches considered. Concepts were selected on the basis of the potential for improving stability limits and achieving emission goals, the technological risks associated with development of practical burners employing the concepts, and the penalties to airline direct operating costs resulting from decreased combustor performance, increased engine cost, increased maintenance cost and increased engine weight associated with implementation of the concepts. Tests of flameholders embodying the selected concepts were conducted.

  5. Polyphosphazene/Nano-Hydroxyapatite Composite Microsphere Scaffolds for Bone Tissue Engineering

    PubMed Central

    Nukavarapu, Syam P.; Kumbar, Sangamesh G.; Brown, Justin L.; Krogman, Nicholas R.; Weikel, Arlin L.; Hindenlang, Mark D.; Nair, Lakshmi S.; Allcock, Harry R; Laurencin, Cato T.

    2009-01-01

    The non-toxic, neutral degradation products of amino acid ester polyphosphazenes make them ideal candidates for in vivo orthopaedic applications. The quest for new osteocompatible materials for load bearing tissue engineering applications has led us to investigate mechanically competent amino acid ester substituted polyphosphazenes. In this study, we have synthesized three biodegradable polyphosphazenes substituted with side groups namely leucine, valine and phenylalanine ethyl esters. Of these polymers, the phenylalanine ethyl ester substituted polyphosphazene showed the highest glass transition temperature (41.6 °C) and hence was chosen as a candidate material for forming composite microspheres with 100 nm sized hydroxyapatite (nHAp). The fabricated composite microspheres were sintered into a three-dimensional (3-D) porous scaffold by adopting a dynamic solvent sintering approach. The composite microsphere scaffolds showed compressive moduli of 46–81 MPa with mean pore diameters in the range of 86–145 µm. The three-dimensional polyphosphazene-nHAp composite microsphere scaffolds showed good osteoblast cell adhesion, proliferation and alkaline phosphatase expression, and are potential suitors for bone tissue engineering applications. PMID:18517248

  6. Output-Based Structural Damage Detection by Using Correlation Analysis Together with Transmissibility

    PubMed Central

    Cao, Hongyou; Liu, Quanmin; Wahab, Magd Abdel

    2017-01-01

    Output-based structural damage detection is becoming increasingly appealing due to its potential in real engineering applications without any restriction regarding excitation measurements. A new transmissibility-based damage detection approach is presented in this study by combining transmissibility with correlation analysis in order to strengthen its performance in discriminating damaged from undamaged scenarios. From this perspective, damage detection strategies are hereafter established by constructing damage-sensitive indicators from a derived transmissibility. A cantilever beam is numerically analyzed to verify the feasibility of the proposed damage detection procedure, and an ASCE (American Society of Civil Engineers) benchmark is henceforth used in the validation for its application in engineering structures. The results of both studies reveal a good performance of the proposed methodology in identifying damaged states from intact states. The comparison between the proposed indicator and the existing indicator also affirms its applicability in damage detection, which might be adopted in further structural health monitoring systems as a discrimination criterion. This study contributed an alternative criterion for transmissibility-based damage detection in addition to the conventional ones. PMID:28773218

  7. Engineered Nanomaterials, Sexy New Technology and Potential Hazards

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Beaulieu, R A

    Engineered nanomaterials enhance exciting new applications that can greatly benefit society in areas of cancer treatments, solar energy, energy storage, and water purification. While nanotechnology shows incredible promise in these and other areas by exploiting nanomaterials unique properties, these same properties can potentially cause adverse health effects to workers who may be exposed during work. Dispersed nanoparticles in air can cause adverse health effects to animals not merely due to their chemical properties but due to their size, structure, shape, surface chemistry, solubility, carcinogenicity, reproductive toxicity, mutagenicity, dermal toxicity, and parent material toxicity. Nanoparticles have a greater likelihood of lungmore » deposition and blood absorption than larger particles due to their size. Nanomaterials can also pose physical hazards due to their unusually high reactivity, which makes them useful as catalysts, but has the potential to cause fires and explosions. Characterization of the hazards (and potential for exposures) associated with nanomaterial development and incorporation in other products is an essential step in the development of nanotechnologies. Developing controls for these hazards are equally important. Engineered controls should be integrated into nanomaterial manufacturing process design according to 10CFR851, DOE Policy 456.1, and DOE Notice 456.1 as safety-related hardware or administrative controls for worker safety. Nanomaterial hazards in a nuclear facility must also meet control requirements per DOE standards 3009, 1189, and 1186. Integration of safe designs into manufacturing processes for new applications concurrent with the developing technology is essential for worker safety. This paper presents a discussion of nanotechnology, nanomaterial properties/hazards and controls.« less

  8. Biological responses to M13 bacteriophage modified titanium surfaces in vitro.

    PubMed

    Sun, Yuhua; Li, Yiting; Wu, Baohua; Wang, Jianxin; Lu, Xiong; Qu, Shuxin; Weng, Jie; Feng, Bo

    2017-08-01

    Phage-based materials have showed great potential in tissue engineering application. However, it is unknown what inflammation response will happen to this kind of materials. This work is to explore the biological responses to M13 bacteriophage (phage) modified titanium surfaces in vitro from the aspects of their interaction with macrophages, osteoblasts and mineralization behavior. Pretreated Ti surface, Ti surfaces with noncrosslinked phage film (APP) and crosslinked phage film (APPG) were compared. Phage films could limit the macrophage adhesion and activity due to inducing adherent-cell apoptosis. The initial inflammatory activity (24h) caused by phage films was relatively high with more production of TNF-α, but in the later stage (7-10days) inflammatory response was reduced with lower TNF-α, IL-6 and higher IL-10. In addition, phage films improved osteoblast adhesion, differentiation, and hydroapatite (HA)-forming via a combination of topographical and biochemcial cues. The noncrosslinked phage film displayed the best immunomodulatory property, osteogenic activity and HA mineralization ability. This work provides better understanding of inflammatory and osteogenetic activity of phage-based materials and contributes to their future application in tissue engineering. In vivo, the bone and immune cells share a common microenvironment, and are being affected by similar cytokines, signaling molecules, transcription factors and membrane receptors. Ideal implants should cause positive biological response, including adequate and appropriate inflammatory reaction, well-balanced bone formation and absorption. Phage-based materials have showed great potential in tissue engineering application. However, at present it is unknown what inflammation response will happen to this kind of materials. A good understanding of the immune response possibly induced by phage-based materials is needed. This work studied the osteoimmunomodulation property of phage films on titanium surface, involving inflammatory response, osteogenic activity and biomineralization ability. It provides more understanding of the phage-based materials and contributes to their future application in tissue engineering. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  9. Screw expander for light duty diesel engines

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Preliminary selection and sizing of a positive displacement screw compressor-expander subsystem for a light-duty adiabatic diesel engine; development of a mathematical model to describe overall efficiencies for the screw compressor and expander; simulation of operation to establish overall efficiency for a range of design parameters and at given engine operating points; simulation to establish potential net power output at light-duty diesel operating points; analytical determination of mass moments of inertia for the rotors and inertia of the compressor-expander subsystem; and preparation of engineering layout drawings of the compressor and expander are discussed. As a result of this work, it was concluded that the screw compressor and expander designed for light-duty diesel engine applications are viable alternatives to turbo-compound systems, with acceptable efficiencies for both units, and only a moderate effect on the transient response.

  10. Cytochrome P450-mediated metabolic engineering: current progress and future challenges.

    PubMed

    Renault, Hugues; Bassard, Jean-Etienne; Hamberger, Björn; Werck-Reichhart, Danièle

    2014-06-01

    Cytochromes P450 catalyze a broad range of regiospecific, stereospecific and irreversible steps in the biosynthetic routes of plant natural metabolites with important applications in pharmaceutical, cosmetic, fragrance and flavour, or polymer industries. They are consequently essential drivers for the engineered bioproduction of such compounds. Two ground-breaking developments of commercial products driven by the engineering of P450s are the antimalarial drug precursor artemisinic acid and blue roses or carnations. Tedious optimizations were required to generate marketable products. Hurdles encountered in P450 engineering and their potential solutions are summarized here. Together with recent technical developments and novel approaches to metabolic engineering, the lessons from this pioneering work should considerably boost exploitation of the amazing P450 toolkit emerging from accelerated sequencing of plant genomes. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Stem Cells in Skeletal Tissue Engineering: Technologies and Models

    PubMed Central

    Langhans, Mark T.; Yu, Shuting; Tuan, Rocky S.

    2017-01-01

    This review surveys the use of pluripotent and multipotent stem cells in skeletal tissue engineering. Specific emphasis is focused on evaluating the function and activities of these cells in the context of development in vivo, and how technologies and methods of stem cell-based tissue engineering for stem cells must draw inspiration from developmental biology. Information on the embryonic origin and in vivo differentiation of skeletal tissues is first reviewed, to shed light on the persistence and activities of adult stem cells that remain in skeletal tissues after embryogenesis. Next, the development and differentiation of pluripotent stem cells is discussed, and some of their advantages and disadvantages in the context of tissue engineering is presented. The final section highlights current use of multipotent adult mesenchymal stem cells, reviewing their origin, differentiation capacity, and potential applications to tissue engineering. PMID:26423296

  12. Rotordynamic Feasibility of a Conceptual Variable-Speed Power Turbine Propulsion System for Large Civil Tilt-Rotor Applications

    NASA Technical Reports Server (NTRS)

    Howard, Samuel

    2012-01-01

    A variable-speed power turbine concept is analyzed for rotordynamic feasibility in a Large Civil Tilt-Rotor (LCTR) class engine. Implementation of a variable-speed power turbine in a rotorcraft engine would enable high efficiency propulsion at the high forward velocities anticipated of large tilt-rotor vehicles. Therefore, rotordynamics is a critical issue for this engine concept. A preliminary feasibility study is presented herein to address this concern and identify if variable-speed is possible in a conceptual engine sized for the LCTR. The analysis considers critical speed placement in the operating speed envelope, stability analysis up to the maximum anticipated operating speed, and potential unbalance response amplitudes to determine that a variable-speed power turbine is likely to be challenging, but not impossible to achieve in a tilt-rotor propulsion engine.

  13. Chitosan microspheres with an extracellular matrix-mimicking nanofibrous structure as cell-carrier building blocks for bottom-up cartilage tissue engineering

    NASA Astrophysics Data System (ADS)

    Zhou, Yong; Gao, Huai-Ling; Shen, Li-Li; Pan, Zhao; Mao, Li-Bo; Wu, Tao; He, Jia-Cai; Zou, Duo-Hong; Zhang, Zhi-Yuan; Yu, Shu-Hong

    2015-12-01

    Scaffolds for tissue engineering (TE) which closely mimic the physicochemical properties of the natural extracellular matrix (ECM) have been proven to advantageously favor cell attachment, proliferation, migration and new tissue formation. Recently, as a valuable alternative, a bottom-up TE approach utilizing cell-loaded micrometer-scale modular components as building blocks to reconstruct a new tissue in vitro or in vivo has been proved to demonstrate a number of desirable advantages compared with the traditional bulk scaffold based top-down TE approach. Nevertheless, micro-components with an ECM-mimicking nanofibrous structure are still very scarce and highly desirable. Chitosan (CS), an accessible natural polymer, has demonstrated appealing intrinsic properties and promising application potential for TE, especially the cartilage tissue regeneration. According to this background, we report here the fabrication of chitosan microspheres with an ECM-mimicking nanofibrous structure for the first time based on a physical gelation process. By combining this physical fabrication procedure with microfluidic technology, uniform CS microspheres (CMS) with controlled nanofibrous microstructure and tunable sizes can be facilely obtained. Especially, no potentially toxic or denaturizing chemical crosslinking agent was introduced into the products. Notably, in vitro chondrocyte culture tests revealed that enhanced cell attachment and proliferation were realized, and a macroscopic 3D geometrically shaped cartilage-like composite can be easily constructed with the nanofibrous CMS (NCMS) and chondrocytes, which demonstrate significant application potential of NCMS as the bottom-up cell-carrier components for cartilage tissue engineering.Scaffolds for tissue engineering (TE) which closely mimic the physicochemical properties of the natural extracellular matrix (ECM) have been proven to advantageously favor cell attachment, proliferation, migration and new tissue formation. Recently, as a valuable alternative, a bottom-up TE approach utilizing cell-loaded micrometer-scale modular components as building blocks to reconstruct a new tissue in vitro or in vivo has been proved to demonstrate a number of desirable advantages compared with the traditional bulk scaffold based top-down TE approach. Nevertheless, micro-components with an ECM-mimicking nanofibrous structure are still very scarce and highly desirable. Chitosan (CS), an accessible natural polymer, has demonstrated appealing intrinsic properties and promising application potential for TE, especially the cartilage tissue regeneration. According to this background, we report here the fabrication of chitosan microspheres with an ECM-mimicking nanofibrous structure for the first time based on a physical gelation process. By combining this physical fabrication procedure with microfluidic technology, uniform CS microspheres (CMS) with controlled nanofibrous microstructure and tunable sizes can be facilely obtained. Especially, no potentially toxic or denaturizing chemical crosslinking agent was introduced into the products. Notably, in vitro chondrocyte culture tests revealed that enhanced cell attachment and proliferation were realized, and a macroscopic 3D geometrically shaped cartilage-like composite can be easily constructed with the nanofibrous CMS (NCMS) and chondrocytes, which demonstrate significant application potential of NCMS as the bottom-up cell-carrier components for cartilage tissue engineering. Electronic supplementary information (ESI) available: Additional figures and table. See DOI: 10.1039/c5nr06876b

  14. A Review on Graphene-Based Nanomaterials in Biomedical Applications and Risks in Environment and Health

    NASA Astrophysics Data System (ADS)

    Dasari Shareena, Thabitha P.; McShan, Danielle; Dasmahapatra, Asok K.; Tchounwou, Paul B.

    2018-07-01

    Graphene-based nanomaterials (GBNs) have attracted increasing interests of the scientific community due to their unique physicochemical properties and their applications in biotechnology, biomedicine, bioengineering, disease diagnosis and therapy. Although a large amount of researches have been conducted on these novel nanomaterials, limited comprehensive reviews are published on their biomedical applications and potential environmental and human health effects. The present research aimed at addressing this knowledge gap by examining and discussing: (1) the history, synthesis, structural properties and recent developments of GBNs for biomedical applications; (2) GBNs uses as therapeutics, drug/gene delivery and antibacterial materials; (3) GBNs applications in tissue engineering and in research as biosensors and bioimaging materials; and (4) GBNs potential environmental effects and human health risks. It also discussed the perspectives and challenges associated with the biomedical applications of GBNs.[Figure not available: see fulltext.

  15. Flexible, Symmetry-Directed Approach To Assembling Protein Cages (Publisher’s Version Open Access)

    DTIC Science & Technology

    2016-08-01

    widespread in nature and confers new biological properties. Engineered protein assemblies have potential applica- tions in nanotechnology and medicine...and nanotechnology in designing novel self-assembling proteins and adapting natural protein assem- blies for a range of applications broadly

  16. Robotics--The New Silent Majority: Engineering Robot Applications and Education.

    ERIC Educational Resources Information Center

    Kimbler, D. L.

    1984-01-01

    The impact of robotics in education is discussed in terms of academic assistance to industry in robotics as well as academic problems in handling the demands put upon it. Some potential solutions that can have lasting impact on educational systems are proposed. (JN)

  17. Type III Polyketide Synthases: Discovery, Characterization, and Engineering

    ERIC Educational Resources Information Center

    Pitel, Sheryl Beth Rubin

    2009-01-01

    The polyketides are a diverse group of natural products with important applications in medicine and industry. Industry, especially the pharmaceutical industry, is under pressure to deliver "greener" chemical syntheses that are less environmentally damaging and incorporate renewable resources. There exists potential to replace current…

  18. Dedicated industrial oilseed crops as metabolic engineering platforms for sustainable industrial feedstock production

    USDA-ARS?s Scientific Manuscript database

    Feedstocks for industrial applications ranging from polymers to lubricants are largely derived from petroleum, a non-renewable resource. Vegetable oils with fatty acid structures and storage forms tailored for specific industrial uses offer renewable and potentially sustainable sources of petrochemi...

  19. Clinical trial perspective for adult and juvenile Huntington's disease using genetically-engineered mesenchymal stem cells

    PubMed Central

    Deng, Peter; Torrest, Audrey; Pollock, Kari; Dahlenburg, Heather; Annett, Geralyn; Nolta, Jan A.; Fink, Kyle D.

    2016-01-01

    Progress to date from our group and others indicate that using genetically-engineered mesenchymal stem cells (MSC) to secrete brain-derived neurotrophic factor (BDNF) supports our plan to submit an Investigational New Drug application to the Food and Drug Administration for the future planned Phase 1 safety and tolerability trial of MSC/BDNF in patients with Huntington's disease (HD). There are also potential applications of this approach beyond HD. Our biological delivery system for BDNF sets the precedent for adult stem cell therapy in the brain and could potentially be modified for other neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS), spinocerebellar ataxia (SCA), Alzheimer's disease, and some forms of Parkinson's disease. The MSC/BDNF product could also be considered for studies of regeneration in traumatic brain injury, spinal cord and peripheral nerve injury. This work also provides a platform for our future gene editing studies, since we will again use MSCs to deliver the needed molecules into the central nervous system. PMID:27335539

  20. High temperature strain gage technology for gas turbine engines

    NASA Technical Reports Server (NTRS)

    Fichtel, Edward J.; Mcdaniel, Amos D.

    1994-01-01

    This report summarizes the results of a six month study that addressed specific issues to transfer the Pd-13Cr static strain sensor to a gas turbine engine environment. The application issues that were addressed include: (1) evaluation of a miniature, variable potentiometer for use as the ballast resistor, in conjunction with a conventional strain gage signal conditioning unit; (2) evaluation of a metal sheathed, platinum conductor leadwire assembly for use with the three-wire sensor; and (3) subjecting the sensor to dynamic strain cyclic testing to determine fatigue characteristics. Results indicate a useful static strain gage system at all temperature levels up to 1350 F. The fatigue characteristics also appear to be very promising, indicating a potential use in dynamic strain measurement applications. The procedure, set-up, and data for all tests are presented in this report. This report also discusses the specific strain gage installation technique for the Pd-13Cr gage because of its potential impact on the quality of the output data.

  1. Artificial intelligence applications concepts for the remote sensing and earth science community

    NASA Technical Reports Server (NTRS)

    Campbell, W. J.; Roelofs, L. H.

    1984-01-01

    The following potential applications of AI to the study of earth science are described: (1) intelligent data management systems; (2) intelligent processing and understanding of spatial data; and (3) automated systems which perform tasks that currently require large amounts of time by scientists and engineers to complete. An example is provided of how an intelligent information system might operate to support an earth science project.

  2. Osteochondral tissue engineering: scaffolds, stem cells and applications

    PubMed Central

    Nooeaid, Patcharakamon; Salih, Vehid; Beier, Justus P; Boccaccini, Aldo R

    2012-01-01

    Osteochondral tissue engineering has shown an increasing development to provide suitable strategies for the regeneration of damaged cartilage and underlying subchondral bone tissue. For reasons of the limitation in the capacity of articular cartilage to self-repair, it is essential to develop approaches based on suitable scaffolds made of appropriate engineered biomaterials. The combination of biodegradable polymers and bioactive ceramics in a variety of composite structures is promising in this area, whereby the fabrication methods, associated cells and signalling factors determine the success of the strategies. The objective of this review is to present and discuss approaches being proposed in osteochondral tissue engineering, which are focused on the application of various materials forming bilayered composite scaffolds, including polymers and ceramics, discussing the variety of scaffold designs and fabrication methods being developed. Additionally, cell sources and biological protein incorporation methods are discussed, addressing their interaction with scaffolds and highlighting the potential for creating a new generation of bilayered composite scaffolds that can mimic the native interfacial tissue properties, and are able to adapt to the biological environment. PMID:22452848

  3. Recent Advances in Biomaterials for 3D Printing and Tissue Engineering

    PubMed Central

    Jammalamadaka, Udayabhanu

    2018-01-01

    Three-dimensional printing has significant potential as a fabrication method in creating scaffolds for tissue engineering. The applications of 3D printing in the field of regenerative medicine and tissue engineering are limited by the variety of biomaterials that can be used in this technology. Many researchers have developed novel biomaterials and compositions to enable their use in 3D printing methods. The advantages of fabricating scaffolds using 3D printing are numerous, including the ability to create complex geometries, porosities, co-culture of multiple cells, and incorporate growth factors. In this review, recently-developed biomaterials for different tissues are discussed. Biomaterials used in 3D printing are categorized into ceramics, polymers, and composites. Due to the nature of 3D printing methods, most of the ceramics are combined with polymers to enhance their printability. Polymer-based biomaterials are 3D printed mostly using extrusion-based printing and have a broader range of applications in regenerative medicine. The goal of tissue engineering is to fabricate functional and viable organs and, to achieve this, multiple biomaterials and fabrication methods need to be researched. PMID:29494503

  4. Recent Advances in Biomaterials for 3D Printing and Tissue Engineering.

    PubMed

    Jammalamadaka, Udayabhanu; Tappa, Karthik

    2018-03-01

    Three-dimensional printing has significant potential as a fabrication method in creating scaffolds for tissue engineering. The applications of 3D printing in the field of regenerative medicine and tissue engineering are limited by the variety of biomaterials that can be used in this technology. Many researchers have developed novel biomaterials and compositions to enable their use in 3D printing methods. The advantages of fabricating scaffolds using 3D printing are numerous, including the ability to create complex geometries, porosities, co-culture of multiple cells, and incorporate growth factors. In this review, recently-developed biomaterials for different tissues are discussed. Biomaterials used in 3D printing are categorized into ceramics, polymers, and composites. Due to the nature of 3D printing methods, most of the ceramics are combined with polymers to enhance their printability. Polymer-based biomaterials are 3D printed mostly using extrusion-based printing and have a broader range of applications in regenerative medicine. The goal of tissue engineering is to fabricate functional and viable organs and, to achieve this, multiple biomaterials and fabrication methods need to be researched.

  5. Perspective of Micro Process Engineering for Thermal Food Treatment

    PubMed Central

    Mathys, Alexander

    2018-01-01

    Micro process engineering as a process synthesis and intensification tool enables an ultra-short thermal treatment of foods within milliseconds (ms) using very high surface-area-to-volume ratios. The innovative application of ultra-short pasteurization and sterilization at high temperatures, but with holding times within the range of ms would allow the preservation of liquid foods with higher qualities, thereby avoiding many unwanted reactions with different temperature–time characteristics. Process challenges, such as fouling, clogging, and potential temperature gradients during such conditions need to be assessed on a case by case basis and optimized accordingly. Owing to the modularity, flexibility, and continuous operation of micro process engineering, thermal processes from the lab to the pilot and industrial scales can be more effectively upscaled. A case study on thermal inactivation demonstrated the feasibility of transferring lab results to the pilot scale. It was shown that micro process engineering applications in thermal food treatment may be relevant to both research and industrial operations. Scaling of micro structured devices is made possible through the use of numbering-up approaches; however, reduced investment costs and a hygienic design must be assured. PMID:29686990

  6. Combining mechanical foaming and thermally induced phase separation to generate chitosan scaffolds for soft tissue engineering.

    PubMed

    Biswas, D P; Tran, P A; Tallon, C; O'Connor, A J

    2017-02-01

    In this paper, a novel foaming methodology consisting of turbulent mixing and thermally induced phase separation (TIPS) was used to generate scaffolds for tissue engineering. Air bubbles were mechanically introduced into a chitosan solution which forms the continuous polymer/liquid phase in the foam created. The air bubbles entrained in the foam act as a template for the macroporous architecture of the final scaffolds. Wet foams were crosslinked via glutaraldehyde and frozen at -20 °C to induce TIPS in order to limit film drainage, bubble coalescence and Ostwald ripening. The effects of production parameters, including mixing speed, surfactant concentration and chitosan concentration, on foaming are explored. Using this method, hydrogel scaffolds were successfully produced with up to 80% porosity, average pore sizes of 120 μm and readily tuneable compressive modulus in the range of 2.6 to 25 kPa relevant to soft tissue engineering applications. These scaffolds supported 3T3 fibroblast cell proliferation and penetration and therefore show significant potential for application in soft tissue engineering.

  7. Esophageal tissue engineering: Current status and perspectives.

    PubMed

    Poghosyan, T; Catry, J; Luong-Nguyen, M; Bruneval, P; Domet, T; Arakelian, L; Sfeir, R; Michaud, L; Vanneaux, V; Gottrand, F; Larghero, J; Cattan, P

    2016-02-01

    Tissue engineering, which consists of the combination and in vivo implantation of elements required for tissue remodeling toward a specific organ phenotype, could be an alternative for classical techniques of esophageal replacement. The current hybrid approach entails creation of an esophageal substitute composed of an acellular matrix and autologous epithelial and muscle cells provides the most successful results. Current research is based on the use of mesenchymal stem cells, whose potential for differentiation and proangioogenic, immune-modulator and anti-inflammatory properties are important assets. In the near future, esophageal substitutes could be constructed from acellular "intelligent matrices" that contain the molecules necessary for tissue regeneration; this should allow circumvention of the implantation step and still obtain standardized in vivo biological responses. At present, tissue engineering applications to esophageal replacement are limited to enlargement plasties with absorbable, non-cellular matrices. Nevertheless, the application of existing clinical techniques for replacement of other organs by tissue engineering in combination with a multiplication of translational research protocols for esophageal replacement in large animals should soon pave the way for health agencies to authorize clinical trials. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  8. Re-engineering the stereoscope for the 21st Century

    NASA Astrophysics Data System (ADS)

    Kollin, Joel S.; Hollander, Ari J.

    2007-02-01

    While discussing the current state of stereo head-mounted and 3D projection displays, the authors came to the realization that flat-panel LCD displays offer higher resolution than projection for stereo display at a low (and continually dropping) cost. More specifically, where head-mounted displays of moderate resolution and field-of-view cost tens of thousands of dollars, we can achieve an angular resolution approaching that of the human eye with a field-of-view (FOV) greater than 90° for less than $1500. For many immersive applications head tracking is unnecessary and sometimes even undesirable, and a low cost/high quality wide FOV display may significantly increase the application space for 3D display. After outlining the problem and potential of this solution we describe the initial construction of a simple Wheatstone stereoscope using 24" LCD displays and then show engineering improvements that increase the FOV and usability of the system. The applicability of a high-immersion, high-resolution display for art, entertainment, and simulation is presented along with a content production system that utilizes the capabilities of the system. We then discuss the potential use of the system for VR pain control therapy, treatment of post-traumatic stress disorders and other serious games applications.

  9. Combinatorial nanodiamond in pharmaceutical and biomedical applications.

    PubMed

    Lim, Dae Gon; Prim, Racelly Ena; Kim, Ki Hyun; Kang, Eunah; Park, Kinam; Jeong, Seong Hoon

    2016-11-30

    One of the newly emerging carbon materials, nanodiamond (ND), has been exploited for use in traditional electric materials and this has extended into biomedical and pharmaceutical applications. Recently, NDs have attained significant interests as a multifunctional and combinational drug delivery system. ND studies have provided insights into granting new potentials with their wide ranging surface chemistry, complex formation with biopolymers, and combination with biomolecules. The studies that have proved ND inertness, biocompatibility, and low toxicity have made NDs much more feasible for use in real in vivo applications. This review gives an understanding of NDs in biomedical engineering and pharmaceuticals, focusing on the classified introduction of ND/drug complexes. In addition, the diverse potential applications that can be obtained with chemical modification are presented. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. A comparative study of the chondrogenic potential between synthetic and natural scaffolds in an in vivo bioreactor

    NASA Astrophysics Data System (ADS)

    Huang, Jung-Ju; Yang, Shu-Rui; Chu, I.-Ming; Brey, Eric M.; Hsiao, Hui-Yi; Cheng, Ming-Huei

    2013-10-01

    The clinical demand for cartilage tissue engineering is potentially large for reconstruction defects resulting from congenital deformities or degenerative disease due to limited donor sites for autologous tissue and donor site morbidities. Cartilage tissue engineering has been successfully applied to the medical field: a scaffold pre-cultured with chondrocytes was used prior to implantation in an animal model. We have developed a surgical approach in which tissues are engineered by implantation with a vascular pedicle as an in vivo bioreactor in bone and adipose tissue engineering. Collagen type II, chitosan, poly(lactic-co-glycolic acid) (PLGA) and polycaprolactone (PCL) were four commonly applied scaffolds in cartilage tissue engineering. To expand the application of the same animal model in cartilage tissue engineering, these four scaffolds were selected and compared for their ability to generate cartilage with chondrocytes in the same model with an in vivo bioreactor. Gene expression and immunohistochemistry staining methods were used to evaluate the chondrogenesis and osteogenesis of specimens. The result showed that the PLGA and PCL scaffolds exhibited better chondrogenesis than chitosan and type II collagen in the in vivo bioreactor. Among these four scaffolds, the PCL scaffold presented the most significant result of chondrogenesis embedded around the vascular pedicle in the long-term culture incubation phase.

  11. CMC`s research in Europe and the future potential of CMC`s in industry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Van de Voorde, M.H.; Nedele, M.R.

    1996-12-31

    CMC`s (Ceramics Matrix Composites) have been developed for high temperature applications in aerospace and military industries. In general, the CMC`s should be capable of outperforming the best available superalloys. Great efforts are being given to pinpoint spin-off technologies i.e. applications in modern fossil fuel power plants, gas turbines, petrochemistry etc. In these applications, the CMC`s have to operate at temperatures up to 1400{degrees}C, in corrosive environments for long durations. These developments will provoke a breakthrough for this new group of CMC-materials. The paper will: (i) give an overview of the CMC`s research in Europe; processing, and characterization of physical, chemicalmore » and engineering properties at high temperatures; (ii) pinpoint the R&D needs to achieve the potential growth; and (iii) review the industrial potentials.« less

  12. Biomaterial-mesenchymal stem cell constructs for immunomodulation in composite tissue engineering.

    PubMed

    Hanson, Summer; D'Souza, Rena N; Hematti, Peiman

    2014-08-01

    Cell-based treatments are being developed as a novel approach for the treatment of many diseases in an effort to repair injured tissues and regenerate lost tissues. Interest in the potential use of multipotent progenitor or stem cells has grown significantly in recent years, specifically the use of mesenchymal stem cells (MSCs), for tissue engineering in combination with extracellular matrix-based scaffolds. An area that warrants further attention is the local or systemic host responses toward the implanted cell-biomaterial constructs. Such immunological responses could play a major role in determining the clinical efficacy of the therapeutic device or biomaterials used. MSCs, due to their unique immunomodulatory properties, hold great promise in tissue engineering as they not only directly participate in tissue repair and regeneration but also modulate the host foreign body response toward the engineered constructs. The purpose of this review was to summarize the current state of knowledge and applications of MSC-biomaterial constructs as a potential immunoregulatory tool in tissue engineering. Better understanding of the interactions between biomaterials and cells could translate to the development of clinically relevant and novel cell-based therapeutics for tissue reconstruction and regenerative medicine.

  13. The Application of Sheet Technology in Cartilage Tissue Engineering.

    PubMed

    Ge, Yang; Gong, Yi Yi; Xu, Zhiwei; Lu, Yanan; Fu, Wei

    2016-04-01

    Cartilage tissue engineering started to act as a promising, even essential alternative method in the process of cartilage repair and regeneration, considering adult avascular structure has very limited self-renewal capacity of cartilage tissue in adults and a bottle-neck existed in conventional surgical treatment methods. Recent progressions in tissue engineering realized the development of more feasible strategies to treat cartilage disorders. Of these strategies, cell sheet technology has shown great clinical potentials in the regenerative areas such as cornea and esophagus and is increasingly considered as a potential way to reconstruct cartilage tissues for its non-use of scaffolds and no destruction of matrix secreted by cultured cells. Acellular matrix sheet technologies utilized in cartilage tissue engineering, with a sandwich model, can ingeniously overcome the drawbacks that occurred in a conventional acellular block, where cells are often blocked from migrating because of the non-nanoporous structure. Electrospun-based sheets with nanostructures that mimic the natural cartilage matrix offer a level of control as well as manipulation and make them appealing and widely used in cartilage tissue engineering. In this review, we focus on the utilization of these novel and promising sheet technologies to construct cartilage tissues with practical and beneficial functions.

  14. Nanomaterials and synergistic low intensity direct current (LIDC) stimulation technology for orthopaedic implantable medical devices

    PubMed Central

    Samberg, Meghan E.; Cohen, Paul H.; Wysk, Richard A.; Monteiro-Riviere, Nancy A.

    2012-01-01

    Nanomaterials play a significant role in biomedical research and applications due to their unique biological, mechanical, and electrical properties. In recent years, they have been utilised to improve the functionality and reliability of a wide range of implantable medical devices ranging from well-established orthopaedic residual hardware devices (e.g. hip implants) that can repair defects in skeletal systems to emerging tissue engineering scaffolds that can repair or replace organ functions. This review summarizes the applications and efficacies of these nanomaterials that include synthetic or naturally occurring metals, polymers, ceramics, and composites in orthopaedic implants, the largest market segment of implantable medical devices. The importance of synergistic engineering techniques that can augment or enhance the performance of nanomaterial applications in orthopaedic implants is also discussed,, the focus being on a low intensity direct electric current (LIDC) stimulation technology to promote the long-term antibacterial efficacy of oligodynamic metal-based surfaces by ionization, while potentially accelerating tissue growth and osseointegration. While many nanomaterials have clearly demonstrated their ability to provide more effective implantable medical surfaces, further decisive investigations are necessary before they can translate into medically safe and commercially viable clinical applications. The paper concludes with a discussion about some of the critical impending issues with the application of nanomaterials-based technologies in implantable medical devices, and potential directions to address these. PMID:23335493

  15. Impacts of engineered nanomaterials on microbial community structure and function in natural and engineered ecosystems.

    PubMed

    Mohanty, Anee; Wu, Yichao; Cao, Bin

    2014-10-01

    In natural and engineered environments, microorganisms often exist as complex communities, which are key to the health of ecosystems and the success of bioprocesses in various engineering applications. With the rapid development of nanotechnology in recent years, engineered nanomaterials (ENMs) have been considered one type of emerging contaminants that pose great potential risks to the proper function of microbial communities in natural and engineered ecosystems. The impacts of ENMs on microorganisms have attracted increasing research attentions; however, most studies focused on the antimicrobial activities of ENMs at single cell and population level. Elucidating the influence of ENMs on microbial communities represents a critical step toward a comprehensive understanding of the ecotoxicity of ENMs. In this mini-review, we summarize and discuss recent research work on the impacts of ENMs on microbial communities in natural and engineered ecosystems, with an emphasis on their influences on the community structure and function. We also highlight several important research topics which may be of great interest to the research community.

  16. Structure-based engineering of an icosahedral virus for nanomedicine and nanotechnology.

    PubMed

    Steinmetz, N F; Lin, T; Lomonossoff, G P; Johnson, J E

    2009-01-01

    A quintessential tenet of nanotechnology is the self-assembly of nanometer-sized components into devices. Biological macromolecular systems such as viral particles were found to be suitable building blocks for nanotechnology for several reasons: viral capsids are extremely robust and can be produced in large quantities with ease, the particles self-assemble into monodisperse particles with a high degree of symmetry and polyvalency, they have the propensity to form arrays, and they offer programmability through genetic and chemical engineering. Here, we review the recent advances in engineering the icosahedral plant virus Cowpea mosaic virus (CPMV) for applications in nano-medicine and -technology. In the first part, we will discuss how the combined knowledge of the structure of CPMV at atomic resolution and the use of chimeric virus technology led to the generation of CPMV particles with short antigenic peptides for potential use as vaccine candidates. The second part focuses on the chemical addressability of CPMV. Strategies to chemically attach functional molecules at designed positions on the exterior surface of the viral particle are described. Biochemical conjugation methods led to the fabrication of electronically conducting CPMV particles and networks. In addition, functional proteins for targeted delivery to mammalian cells were successfully attached to CPMV. In the third part, we focus on the utilization of CPMV as a building block for the generation of 2D and 3D arrays. Overall, the potential applications of viral nanobuilding blocks are manifold and range from nanoelectronics to biomedical applications.

  17. Stirling engine design manual

    NASA Technical Reports Server (NTRS)

    Martini, W. R.

    1978-01-01

    This manual is intended to serve both as an introduction to Stirling engine analysis methods and as a key to the open literature on Stirling engines. Over 800 references are listed and these are cross referenced by date of publication, author and subject. Engine analysis is treated starting from elementary principles and working through cycles analysis. Analysis methodologies are classified as first, second or third order depending upon degree of complexity and probable application; first order for preliminary engine studies, second order for performance prediction and engine optimization, and third order for detailed hardware evaluation and engine research. A few comparisons between theory and experiment are made. A second order design procedure is documented step by step with calculation sheets and a worked out example to follow. Current high power engines are briefly described and a directory of companies and individuals who are active in Stirling engine development is included. Much remains to be done. Some of the more complicated and potentially very useful design procedures are now only referred to. Future support will enable a more thorough job of comparing all available design procedures against experimental data which should soon be available.

  18. Geotechnical engineering for ocean waste disposal. An introduction

    USGS Publications Warehouse

    Lee, Homa J.; Demars, Kenneth R.; Chaney, Ronald C.; ,

    1990-01-01

    As members of multidisciplinary teams, geotechnical engineers apply quantitative knowledge about the behavior of earth materials toward designing systems for disposing of wastes in the oceans and monitoring waste disposal sites. In dredge material disposal, geotechnical engineers assist in selecting disposal equipment, predict stable characteristics of dredge mounds, design mound caps, and predict erodibility of the material. In canister disposal, geotechnical engineers assist in specifying canister configurations, predict penetration depths into the seafloor, and predict and monitor canister performance following emplacement. With sewage outfalls, geotechnical engineers design foundation and anchor elements, estimate scour potential around the outfalls, and determine the stability of deposits made up of discharged material. With landfills, geotechnical engineers evaluate the stability and erodibility of margins and estimate settlement and cracking of the landfill mass. Geotechnical engineers also consider the influence that pollutants have on the engineering behavior of marine sediment and the extent to which changes in behavior affect the performance of structures founded on the sediment. In each of these roles, careful application of geotechnical engineering principles can contribute toward more efficient and environmentally safe waste disposal operations.

  19. SCD's uncooled detectors and video engines for a wide-range of applications

    NASA Astrophysics Data System (ADS)

    Fraenkel, A.; Mizrahi, U.; Bikov, L.; Giladi, A.; Shiloah, N.; Elkind, S.; Kogan, I.; Maayani, S.; Amsterdam, A.; Vaserman, I.; Duman, O.; Hirsh, Y.; Schapiro, F.; Tuito, A.; Ben-Ezra, M.

    2011-06-01

    Over the last decade SCD has established a state of the art VOx μ-Bolometer product line. Due to its overall advantages this technology is penetrating a large range of systems. In addition to a large variety of detectors, SCD has also recently introduced modular video engines with an open architecture. In this paper we will describe the versatile applications supported by the products based on 17μm pitch: Low SWaP short range systems, mid range systems based on VGA arrays and high-end systems that will utilize the XGA format. These latter systems have the potential to compete with cooled 2nd Gen scanning LWIR arrays, as will be demonstrated by TRM3 system level calculations.

  20. Nanotechnology: emerging tool for diagnostics and therapeutics.

    PubMed

    Chakraborty, Mainak; Jain, Surangna; Rani, Vibha

    2011-11-01

    Nanotechnology is an emerging technology which is an amalgamation of different aspects of science and technology that includes disciplines such as electrical engineering, mechanical engineering, biology, physics, chemistry, and material science. It has potential in the fields of information and communication technology, biotechnology, and medicinal technology. It involves manipulating the dimensions of nanoparticles at an atomic scale to make use of its physical and chemical properties. All these properties are responsible for the wide application of nanoparticles in the field of human health care. Promising new technologies based on nanotechnology are being utilized to improve diverse aspects of medical treatments like diagnostics, imaging, and gene and drug delivery. This review summarizes the most promising nanomaterials and their application in human health.

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