Sample records for unique engineering challenges

  1. Challenges for Engineering Design, Construction, and Maintenance of Infrastructure in Afghanistan

    DTIC Science & Technology

    2010-11-01

    applied engineering expertise that collectively can solve challenging infra- structure problems. USACE-ERDC’s researchers and engineers are field...Development Center (ERDC) possesses a unique combination of basic research and applied engineering expertise that collectively can solve challenging...restoration, and other projects. The USACE Engineer Research and Development Center (ERDC) possesses a unique combination of basic research and applied

  2. Transforming Teaching Challenges into Learning Opportunities: Interdisciplinary Reflective Collaboration

    ERIC Educational Resources Information Center

    Callaghan, Ronel

    2015-01-01

    Teaching in higher education poses unique sets of challenges, especially for academics in the engineering, built sciences and information science education disciplines. This article focuses on how reflective collaboration can support academics in their quest to find unique solutions to challenges in different academic contexts. A reflective…

  3. Promoting Collaborative Problem-Solving Skills in a Course on Engineering Grand Challenges

    ERIC Educational Resources Information Center

    Zou, Tracy X. P.; Mickleborough, Neil C.

    2015-01-01

    The ability to solve problems with people of diverse backgrounds is essential for engineering graduates. A course on engineering grand challenges was designed to promote collaborative problem-solving (CPS) skills. One unique component is that students need to work both within their own team and collaborate with the other team to tackle engineering…

  4. SSME lifetime prediction and verification, integrating environments, structures, materials: The challenge

    NASA Technical Reports Server (NTRS)

    Ryan, R. S.; Salter, L. D.; Young, G. M., III; Munafo, P. M.

    1985-01-01

    The planned missions for the space shuttle dictated a unique and technology-extending rocket engine. The high specific impulse requirements in conjunction with a 55-mission lifetime, plus volume and weight constraints, produced unique structural design, manufacturing, and verification requirements. Operations from Earth to orbit produce severe dynamic environments, which couple with the extreme pressure and thermal environments associated with the high performance, creating large low cycle loads and high alternating stresses above endurance limit which result in high sensitivity to alternating stresses. Combining all of these effects resulted in the requirements for exotic materials, which are more susceptible to manufacturing problems, and the use of an all-welded structure. The challenge of integrating environments, dynamics, structures, and materials into a verified SSME structure is discussed. The verification program and developmental flight results are included. The first six shuttle flights had engine performance as predicted with no failures. The engine system has met the basic design challenges.

  5. The 4A Metric Algorithm: A Unique E-Learning Engineering Solution Designed via Neuroscience to Counter Cheating and Reduce Its Recidivism by Measuring Student Growth through Systemic Sequential Online Learning

    ERIC Educational Resources Information Center

    Osler, James Edward

    2016-01-01

    This paper provides a novel instructional methodology that is a unique E-Learning engineered "4A Metric Algorithm" designed to conceptually address the four main challenges faced by 21st century students, who are tempted to cheat in a myriad of higher education settings (face to face, hybrid, and online). The algorithmic online…

  6. Advanced Stirling Radioisotope Generator Life Certification Plan

    NASA Technical Reports Server (NTRS)

    Rusick, Jeffrey J.; Zampino, Edward J.

    2013-01-01

    An Advanced Stirling Radioisotope Generator (ASRG) power supply is being developed by the Department of Energy (DOE) in partnership with NASA for potential future deep space science missions. Unlike previous radioisotope power supplies for space exploration, such as the passive MMRTG used recently on the Mars Curiosity rover, the ASRG is an active dynamic power supply with moving Stirling engine mechanical components. Due to the long life requirement of 17 years and the dynamic nature of the Stirling engine, the ASRG project faced some unique challenges trying to establish full confidence that the power supply will function reliably over the mission life. These unique challenges resulted in the development of an overall life certification plan that emphasizes long-term Stirling engine test and inspection when analysis is not practical. The ASRG life certification plan developed is described.

  7. Molecular engineering with artificial atoms: designing a material platform for scalable quantum spintronics and photonics

    NASA Astrophysics Data System (ADS)

    Doty, Matthew F.; Ma, Xiangyu; Zide, Joshua M. O.; Bryant, Garnett W.

    2017-09-01

    Self-assembled InAs Quantum Dots (QDs) are often called "artificial atoms" and have long been of interest as components of quantum photonic and spintronic devices. Although there has been substantial progress in demonstrating optical control of both single spins confined to a single QD and entanglement between two separated QDs, the path toward scalable quantum photonic devices based on spins remains challenging. Quantum Dot Molecules, which consist of two closely-spaced InAs QDs, have unique properties that can be engineered with the solid state analog of molecular engineering in which the composition, size, and location of both the QDs and the intervening barrier are controlled during growth. Moreover, applied electric, magnetic, and optical fields can be used to modulate, in situ, both the spin and optical properties of the molecular states. We describe how the unique photonic properties of engineered Quantum Dot Molecules can be leveraged to overcome long-standing challenges to the creation of scalable quantum devices that manipulate single spins via photonics.

  8. Hydrogel scaffolds for tissue engineering: Progress and challenges

    PubMed Central

    El-Sherbiny, Ibrahim M.; Yacoub, Magdi H.

    2013-01-01

    Designing of biologically active scaffolds with optimal characteristics is one of the key factors for successful tissue engineering. Recently, hydrogels have received a considerable interest as leading candidates for engineered tissue scaffolds due to their unique compositional and structural similarities to the natural extracellular matrix, in addition to their desirable framework for cellular proliferation and survival. More recently, the ability to control the shape, porosity, surface morphology, and size of hydrogel scaffolds has created new opportunities to overcome various challenges in tissue engineering such as vascularization, tissue architecture and simultaneous seeding of multiple cells. This review provides an overview of the different types of hydrogels, the approaches that can be used to fabricate hydrogel matrices with specific features and the recent applications of hydrogels in tissue engineering. Special attention was given to the various design considerations for an efficient hydrogel scaffold in tissue engineering. Also, the challenges associated with the use of hydrogel scaffolds were described. PMID:24689032

  9. STEM Intervention Programs: Funding Practices and Challenges

    ERIC Educational Resources Information Center

    Rincon, Blanca E.; George-Jackson, Casey E.

    2016-01-01

    This study examines the funding practices and challenges of diversity initiatives found in the science, technology, engineering, and mathematics (STEM) fields. Interviews with 55 intervention program administrators, representing 48 unique STEM intervention programs, were conducted at nine large research-intensive universities. The interviews,…

  10. Chemical engineering challenges and investment opportunities in sustainable energy.

    PubMed

    Heller, Adam

    2008-01-01

    The chemical and energy industries are transforming as they adjust to the new era of high-priced petroleum and severe global warming. As a result of the transformation, engineering challenges and investment opportunities abound. Rapid evolution and fast growth are expected in cathode and anode materials as well as polymeric electrolytes for vehicular batteries and in high-performance polymer-ceramic composites for wind turbines, fuel-efficient aircraft, and lighter and safer cars. Unique process-engineering opportunities exist in sand-oil, coal, and possibly also shale liquefaction to produce transportation fuel; and also in genetic engineering of photosynthesizing plants and other organisms for their processing into high-performance biodegradable polymers and high-value-added environmentally friendly chemicals. Also, research on the feasibility of mitigation of global warming through enhancement of CO(2) uptake by the southern oceans by fertilization with trace amounts of iron is progressing. Because chemical engineers are uniquely well trained in mathematical modeling of mass transport, flow, and mixing, and also in cost analysis, they are likely to join the oceanographers and marine biologists in this important endeavor.

  11. Systems engineering for very large systems

    NASA Technical Reports Server (NTRS)

    Lewkowicz, Paul E.

    1993-01-01

    Very large integrated systems have always posed special problems for engineers. Whether they are power generation systems, computer networks or space vehicles, whenever there are multiple interfaces, complex technologies or just demanding customers, the challenges are unique. 'Systems engineering' has evolved as a discipline in order to meet these challenges by providing a structured, top-down design and development methodology for the engineer. This paper attempts to define the general class of problems requiring the complete systems engineering treatment and to show how systems engineering can be utilized to improve customer satisfaction and profit ability. Specifically, this work will focus on a design methodology for the largest of systems, not necessarily in terms of physical size, but in terms of complexity and interconnectivity.

  12. Systems engineering for very large systems

    NASA Astrophysics Data System (ADS)

    Lewkowicz, Paul E.

    Very large integrated systems have always posed special problems for engineers. Whether they are power generation systems, computer networks or space vehicles, whenever there are multiple interfaces, complex technologies or just demanding customers, the challenges are unique. 'Systems engineering' has evolved as a discipline in order to meet these challenges by providing a structured, top-down design and development methodology for the engineer. This paper attempts to define the general class of problems requiring the complete systems engineering treatment and to show how systems engineering can be utilized to improve customer satisfaction and profit ability. Specifically, this work will focus on a design methodology for the largest of systems, not necessarily in terms of physical size, but in terms of complexity and interconnectivity.

  13. Engineering complex tissues.

    PubMed

    Atala, Anthony; Kasper, F Kurtis; Mikos, Antonios G

    2012-11-14

    Tissue engineering has emerged at the intersection of numerous disciplines to meet a global clinical need for technologies to promote the regeneration of functional living tissues and organs. The complexity of many tissues and organs, coupled with confounding factors that may be associated with the injury or disease underlying the need for repair, is a challenge to traditional engineering approaches. Biomaterials, cells, and other factors are needed to design these constructs, but not all tissues are created equal. Flat tissues (skin); tubular structures (urethra); hollow, nontubular, viscus organs (vagina); and complex solid organs (liver) all present unique challenges in tissue engineering. This review highlights advances in tissue engineering technologies to enable regeneration of complex tissues and organs and to discuss how such innovative, engineered tissues can affect the clinic.

  14. Shuttle Propulsion Overview - The Design Challenges

    NASA Technical Reports Server (NTRS)

    Owen, James W.

    2011-01-01

    The major elements of the Space Shuttle Main Propulsion System include two reusable solid rocket motors integrated into recoverable solid rocket boosters, an expendable external fuel and oxidizer tank, and three reusable Space Shuttle Main Engines. Both the solid rocket motors and space shuttle main engines ignite prior to liftoff, with the solid rocket boosters separating about two minutes into flight. The external tank separates, about eight and a half minutes into the flight, after main engine shutdown and is safely expended in the ocean. The SSME's, integrated into the Space Shuttle Orbiter aft structure, are reused after post landing inspections. The configuration is called a stage and a half as all the propulsion elements are active during the boost phase, with only the SSME s continuing operation to achieve orbital velocity. Design and performance challenges were numerous, beginning with development work in the 1970's. The solid rocket motors were large, and this technology had never been used for human space flight. The SSME s were both reusable and very high performance staged combustion cycle engines, also unique to the Space Shuttle. The multi body side mount configuration was unique and posed numerous integration and interface challenges across the elements. Operation of the system was complex and time consuming. This paper describes the design challenges and key areas where the design evolved during the program.

  15. FHWA and USGS cooperate to provide environmental engineering/science curricula developed for the stochastic empirical loading and dilution model (SELDM) to universities and colleges.

    DOT National Transportation Integrated Search

    2016-01-01

    Managers and engineers at the Federal Highway Administration (FHWA) and State Departments of Transportation (DOTs) indicate that they need researchers, employees, consultants, and regulators who understand the unique challenges involved in managing a...

  16. Technology Challenges for Deep-Throttle Cryogenic Engines for Space Exploration

    NASA Technical Reports Server (NTRS)

    Brown, Kendall K.; Nelson, Karl W.

    2005-01-01

    Historically, cryogenic rocket engines have not been used for in-space applications due to their additional complexity, the mission need for high reliability, and the challenges of propellant boil-off. While the mission and vehicle architectures are not yet defined for the lunar and Martian robotic and human exploration objectives, cryogenic rocket engines offer the potential for higher performance and greater architecture/mission flexibility. In-situ cryogenic propellant production could enable a more robust exploration program by significantly reducing the propellant mass delivered to low earth orbit, thus warranting the evaluation of cryogenic rocket engines versus the hypergolic bi-propellant engines used in the Apollo program. A multi-use engine. one which can provide the functionality that separate engines provided in the Apollo mission architecture, is desirable for lunar and Mars exploration missions because it increases overall architecture effectiveness through commonality and modularity. The engine requirement derivation process must address each unique mission application and each unique phase within each mission. The resulting requirements, such as thrust level, performance, packaging, bum duration, number of operations; required impulses for each trajectory phase; operation after extended space or surface exposure; availability for inspection and maintenance; throttle range for planetary descent, ascent, acceleration limits and many more must be addressed. Within engine system studies, the system and component technology, capability, and risks must be evaluated and a balance between the appropriate amount of technology-push and technology-pull must be addressed. This paper will summarize many of the key technology challenges associated with using high-performance cryogenic liquid propellant rocket engine systems and components in the exploration program architectures. The paper is divided into two areas. The first area describes how the mission requirements affect the engine system requirements and create system level technology challenges. An engine system architecture for multiple applications or a family of engines based upon a set of core technologies, design, and fabrication approaches may reduce overall programmatic cost and risk. The engine system discussion will also address the characterization of engine cycle figures of merit, configurations, and design approaches for some in-space vehicle alternatives under consideration. The second area evaluates the component-level technology challenges induced from the system requirements. Component technology issues are discussed addressing injector, thrust chamber, ignition system, turbopump assembly, and valve design for the challenging requirements of high reliability, robustness, fault tolerance, deep throttling, reasonable performance (with respect to weight and specific impulse).

  17. Technology Challenges for Deep-Throttle Cryogenic Engines for Space Exploration

    NASA Astrophysics Data System (ADS)

    Brown, Kendall K.; Nelson, Karl W.

    2005-02-01

    Historically, cryogenic rocket engines have not been used for in-space applications due to their additional complexity, the mission need for high reliability, and the challenges of propellant boil-off. While the mission and vehicle architectures are not yet defined for the lunar and Martian robotic and human exploration objectives, cryogenic rocket engines offer the potential for higher performance and greater architecture/mission flexibility. In-situ cryogenic propellant production could enable a more robust exploration program by significantly reducing the propellant mass delivered to low earth orbit, thus warranting the evaluation of cryogenic rocket engines versus the hypergolic bipropellant engines used in the Apollo program. A multi-use engine, one which can provide the functionality that separate engines provided in the Apollo mission architecture, is desirable for lunar and Mars exploration missions because it increases overall architecture effectiveness through commonality and modularity. The engine requirement derivation process must address each unique mission application and each unique phase within each mission. The resulting requirements, such as thrust level, performance, packaging, burn duration, number of operations; required impulses for each trajectory phase; operation after extended space or surface exposure; availability for inspection and maintenance; throttle range for planetary descent, ascent, acceleration limits and many more must be addressed. Within engine system studies, the system and component technology, capability, and risks must be evaluated and a balance between the appropriate amount of technology-push and technology-pull must be addressed. This paper will summarize many of the key technology challenges associated with using high-performance cryogenic liquid propellant rocket engine systems and components in the exploration program architectures. The paper is divided into two areas. The first area describes how the mission requirements affect the engine system requirements and create system level technology challenges. An engine system architecture for multiple applications or a family of engines based upon a set of core technologies, design, and fabrication approaches may reduce overall programmatic cost and risk. The engine system discussion will also address the characterization of engine cycle figures of merit, configurations, and design approaches for some in-space vehicle alternatives under consideration. The second area evaluates the component-level technology challenges induced from the system requirements. Component technology issues are discussed addressing injector, thrust chamber, ignition system, turbopump assembly, and valve design for the challenging requirements of high reliability, robustness, fault tolerance, deep throttling, reasonable performance (with respect to weight and specific impulse).

  18. Tendon Tissue Engineering: Progress, Challenges, and Translation to the Clinic

    PubMed Central

    Shearn, Jason T.; Kinneberg, Kirsten R.C.; Dyment, Nathaniel A.; Galloway, Marc T.; Kenter, Keith; Wylie, Christopher; Butler, David L.

    2013-01-01

    The tissue engineering field has made great strides in understanding how different aspects of tissue engineered constructs (TECs) and the culture process affect final tendon repair. However, there remain significant challenges in developing strategies that will lead to a clinically effective and commercially successful product. In an effort to increase repair quality, a better understanding of normal development, and how it differs from adult tendon healing, may provide strategies to improve tissue engineering. As tendon tissue engineering continues to improve, the field needs to employ more clinically relevant models of tendon injury such as degenerative tendons. We need to translate successes to larger animal models to begin exploring the clinical implications of our treatments. By advancing the models used to validate our TECs, we can help convince our toughest customer, the surgeon, that our products will be clinically efficacious. As we address these challenges in musculoskeletal tissue engineering, the field still needs to address the commercialization of products developed in the laboratory. TEC commercialization faces numerous challenges because each injury and patient is unique. This review aims to provide tissue engineers with a summary of important issues related to engineering tendon repairs and potential strategies for producing clinically successful products. PMID:21625053

  19. Career-Life Balance for Women of Color: Experiences in Science and Engineering Academia

    ERIC Educational Resources Information Center

    Kachchaf, Rachel; Ko, Lily; Hodari, Apriel; Ong, Maria

    2015-01-01

    The National Science Foundation recently recognized that career-life balance in science, technology, engineering, and mathematics (STEM) may present some unique challenges for women of color compared with their White and/or male counterparts, thus negatively impacting retention and advancement for a minority demographic that has long been…

  20. Integrating International Engineering Organizations For Successful ISS Operations

    NASA Technical Reports Server (NTRS)

    Blome, Elizabeth; Duggan, Matt; Patten, L.; Pieterek, Hhtrud

    2006-01-01

    The International Space Station (ISS) is a multinational orbiting space laboratory that is built in cooperation with 16 nations. The design and sustaining engineering expertise is spread worldwide. As the number of Partners with orbiting elements on the ISS grows, the challenge NASA is facing as the ISS integrator is to ensure that engineering expertise and data are accessible in a timely fashion to ensure ongoing operations and mission success. Integrating international engineering teams requires definition and agreement on common processes and responsibilities, joint training and the emergence of a unique engineering team culture. ISS engineers face daunting logistical and political challenges regarding data sharing requirements. To assure systematic information sharing and anomaly resolution of integrated anomalies, the ISS Partners are developing multi-lateral engineering interface procedures. Data sharing and individual responsibility are key aspects of this plan. This paper describes several examples of successful multilateral anomaly resolution. These successes were used to form the framework of the Partner to Partner engineering interface procedures, and this paper describes those currently documented multilateral engineering processes. Furthermore, it addresses the challenges experienced to date, and the forward work expected in establishing a successful working relationship with Partners as their hardware is launched.

  1. Linde FUSRAP Site Remediation: Engineering Challenges and Solutions of Remedial Activities on an Active Industrial Facility - 13506

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

    Beres, Christopher M.; Fort, E. Joseph; Boyle, James D.

    2013-07-01

    The Linde FUSRAP Site (Linde) is located in Tonawanda, New York at a major research and development facility for Praxair, Inc. (Praxair). Successful remediation activities at Linde combines meeting cleanup objectives of radiological contamination while minimizing impacts to Praxair business operations. The unique use of Praxair's property coupled with an array of active and abandoned utilities poses many engineering and operational challenges; each of which has been overcome during the remedial action at Linde. The U.S. Army Corps of Engineers - Buffalo District (USACE) and CABRERA SERVICES, INC. (CABRERA) have successfully faced engineering challenges such as relocation of an abovegroundmore » structure, structural protection of an active water line, and installation of active mechanical, electrical, and communication utilities to perform remediation. As remediation nears completion, continued success of engineering challenges is critical as remaining activities exist in the vicinity of infrastructure essential to business operations; an electrical substation and duct bank providing power throughout the Praxair facility. Emphasis on engineering and operations through final remediation and into site restoration will allow for the safe and successful completion of the project. (authors)« less

  2. Remediation of water and wastewater by using engineered nanomaterials: A review.

    PubMed

    Bishoge, Obadia K; Zhang, Lingling; Suntu, Shaldon L; Jin, Hui; Zewde, Abraham A; Qi, Zhongwei

    2018-05-12

    Nanotechnology is currently a fast-rising socioeconomic and political knowledge-based technology owing to the unique characteristics of its engineered nanomaterials. This branch of technology is useful for water and wastewater remediation. Many scientists and researchers have been conducting different studies and experiments on the applications of engineered nanomaterials at the local to international level. This review mainly aims to provide a current overview of existing knowledge on engineered nanomaterials and their applications in water and wastewater remediation. Furthermore, the present risks and challenges of nanotechnology are examined.

  3. Synthetic Immunology: Hacking Immune Cells to Expand Their Therapeutic Capabilities.

    PubMed

    Roybal, Kole T; Lim, Wendell A

    2017-04-26

    The ability of immune cells to survey tissues and sense pathologic insults and deviations makes them a unique platform for interfacing with the body and disease. With the rapid advancement of synthetic biology, we can now engineer and equip immune cells with new sensors and controllable therapeutic response programs to sense and treat diseases that our natural immune system cannot normally handle. Here we review the current state of engineered immune cell therapeutics and their unique capabilities compared to small molecules and biologics. We then discuss how engineered immune cells are being designed to combat cancer, focusing on how new synthetic biology tools are providing potential ways to overcome the major roadblocks for treatment. Finally, we give a long-term vision for the use of synthetic biology to engineer immune cells as a general sensor-response platform to precisely detect disease, to remodel disease microenvironments, and to treat a potentially wide range of challenging diseases.

  4. Overview of Engineering Design and Analysis at the NASA John C. Stennis Space Center

    NASA Technical Reports Server (NTRS)

    Ryan, Harry; Congiardo, Jared; Junell, Justin; Kirkpatrick, Richard

    2007-01-01

    A wide range of rocket propulsion test work occurs at the NASA John C. Stennis Space Center (SSC) including full-scale engine test activities at test facilities A-1, A-2, B-1 and B-2 as well as combustion device research and development activities at the E-Complex (E-1, E-2, E-3 and E-4) test facilities. The propulsion test engineer at NASA SSC faces many challenges associated with designing and operating a test facility due to the extreme operating conditions (e.g., cryogenic temperatures, high pressures) of the various system components and the uniqueness of many of the components and systems. The purpose of this paper is to briefly describe the NASA SSC Engineering Science Directorate s design and analysis processes, experience, and modeling techniques that are used to design and support the operation of unique rocket propulsion test facilities.

  5. Synthetic Immunology: Hacking Immune Cells to Expand Their Therapeutic Capabilities

    PubMed Central

    Roybal, Kole T.; Lim, Wendell A.

    2017-01-01

    The ability of immune cells to survey tissues and sense pathologic insults and deviations makes them a unique platform for interfacing with the body and disease. With the rapid advancement of synthetic biology, we can now engineer and equip immune cells with new sensors and controllable therapeutic response programs to sense and treat diseases that our natural immune system cannot normally handle. Here we review the current state of engineered immune cell therapeutics and their unique capabilities compared to small molecules and biologics. We then discuss how engineered immune cells are being designed to combat cancer, focusing on how new synthetic biology tools are providing potential ways to overcome the major roadblocks for treatment. Finally, we give a long-term vision for the use of synthetic biology to engineer immune cells as a general sensor-response platform to precisely detect disease, to remodel disease microenvironments, and to treat a potentially wide range of challenging diseases. PMID:28446063

  6. NASA Space Rocket Logistics Challenges

    NASA Technical Reports Server (NTRS)

    Neeley, James R.; Jones, James V.; Watson, Michael D.; Bramon, Christopher J.; Inman, Sharon K.; Tuttle, Loraine

    2014-01-01

    The Space Launch System (SLS) is the new NASA heavy lift launch vehicle and is scheduled for its first mission in 2017. The goal of the first mission, which will be uncrewed, is to demonstrate the integrated system performance of the SLS rocket and spacecraft before a crewed flight in 2021. SLS has many of the same logistics challenges as any other large scale program. Common logistics concerns for SLS include integration of discreet programs geographically separated, multiple prime contractors with distinct and different goals, schedule pressures and funding constraints. However, SLS also faces unique challenges. The new program is a confluence of new hardware and heritage, with heritage hardware constituting seventy-five percent of the program. This unique approach to design makes logistics concerns such as commonality especially problematic. Additionally, a very low manifest rate of one flight every four years makes logistics comparatively expensive. That, along with the SLS architecture being developed using a block upgrade evolutionary approach, exacerbates long-range planning for supportability considerations. These common and unique logistics challenges must be clearly identified and tackled to allow SLS to have a successful program. This paper will address the common and unique challenges facing the SLS programs, along with the analysis and decisions the NASA Logistics engineers are making to mitigate the threats posed by each.

  7. Engineering industrial yeast for renewable advanced biofuels applications

    USDA-ARS?s Scientific Manuscript database

    The industrial yeast Saccharomyces cerevisiae is a candidate for the next-generation biocatalyst development due to its unique genomic background and robust performance in fermentation-based production. In order to meet challenges of renewable and sustainable advanced biofuels conversion including ...

  8. A Systems-Level Approach to Characterizing Effects of ENMs in Terrestrial Organisms and Ecosystems

    EPA Science Inventory

    Engineered nanomaterials (ENMs) represent a new regulatory challenge because of their unique properties and their potential to interact with ecological organisms at various developmental stages, in numerous environmental compartments. Traditional toxicity tests have proven to be...

  9. Industrial brewing yeast engineered for the production of primary flavor determinants in hopped beer.

    PubMed

    Denby, Charles M; Li, Rachel A; Vu, Van T; Costello, Zak; Lin, Weiyin; Chan, Leanne Jade G; Williams, Joseph; Donaldson, Bryan; Bamforth, Charles W; Petzold, Christopher J; Scheller, Henrik V; Martin, Hector Garcia; Keasling, Jay D

    2018-03-20

    Flowers of the hop plant provide both bitterness and "hoppy" flavor to beer. Hops are, however, both a water and energy intensive crop and vary considerably in essential oil content, making it challenging to achieve a consistent hoppy taste in beer. Here, we report that brewer's yeast can be engineered to biosynthesize aromatic monoterpene molecules that impart hoppy flavor to beer by incorporating recombinant DNA derived from yeast, mint, and basil. Whereas metabolic engineering of biosynthetic pathways is commonly enlisted to maximize product titers, tuning expression of pathway enzymes to affect target production levels of multiple commercially important metabolites without major collateral metabolic changes represents a unique challenge. By applying state-of-the-art engineering techniques and a framework to guide iterative improvement, strains are generated with target performance characteristics. Beers produced using these strains are perceived as hoppier than traditionally hopped beers by a sensory panel in a double-blind tasting.

  10. Modular projects and 'mean questions': best practices for advising an International Genetically Engineered Machines team.

    PubMed

    Tsui, Jennifer; Meyer, Anne S

    2016-07-01

    In the yearly Internationally Genetically Engineered Machines (iGEM) competition, teams of Bachelor's and Master's students design and build an engineered biological system using DNA technologies. Advising an iGEM team poses unique challenges due to the inherent difficulties of mounting and completing a new biological project from scratch over the course of a single academic year; the challenges in obtaining financial and structural resources for a project that will likely not be fully realized; and conflicts between educational and competition-based goals. This article shares tips and best practices for iGEM team advisors, from two team advisors with very different experiences with the iGEM competition. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Resilient and Corrosion-proof Rolling Element Bearings Made from Ni-ti Alloys for Aerospace Mechanism Applications and the Ultimate Space Technology Development Platform

    NASA Technical Reports Server (NTRS)

    Dellacorte, Christopher

    2014-01-01

    The International Space Station provides a unique microgravity laboratory environment for research. The ISS also serves as an effective platform for the development of technologies and engineered solutions related to living and working in space. The space environment also challenges our capabilities related to lubrication and tribology. In this seminar, Dr. DellaCorte will review the basics of space mechanism tribology and the challenges of providing good lubrication and long-life in the harsh space environment. He will also discuss recent tribological challenges associated with the Solar Alpha Rotary Joint (SARJ) bearings and life support hardware that must operate under severe conditions that are literally out of this world. Each tribology challenge is unique and their solutions often result in new technologies that benefit the tribology community everywhere, even back on Earth

  12. Cell and Tissue Engineering for Liver Disease

    PubMed Central

    Bhatia, Sangeeta N.; Underhill, Gregory H.; Zaret, Kenneth S.; Fox, Ira J.

    2015-01-01

    Despite the tremendous hurdles presented by the complexity of the liver’s structure and function, advances in liver physiology, stem cell biology and reprogramming, and the engineering of tissues and devices are accelerating the development of cell-based therapies for treating liver disease and liver failure. This State of the Art Review discusses both the near and long-term prospects for such cell-based therapies and the unique challenges for clinical translation. PMID:25031271

  13. Practical application of AMLCDs for tactical fighter aircraft

    NASA Astrophysics Data System (ADS)

    McClaskey, Paul; Craddock, Roger

    1995-06-01

    Development and testing of an AMLCD-display to replace a dichroic display in a fighter aircraft environment has presented a unique set of technical challenges. This paper addresses design concepts used on the Engine Fuel Display and proposes design guidelines generally applicable for AMLCD projects.

  14. Master of Engineering Energy Systems Engineering Program: Smart Campus Energy Systems Demonstration DE-SC0005523

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

    Dodge, Martha; Coulter, John

    2014-09-25

    Program Purpose and Position: The mission of the Master of Engineering in Energy Systems Engineering program is to invigorate the pipeline of new engineering graduates interested in energy oriented careers and thus produce a new generation of technical leaders for the energy and power industries. Over the next decade, nearly 50% of the skilled workers and technical leaders in the gas and electric utility industries will retire -- a much larger void than the current available and qualified professionals could fill [CEWD, 2012 survey]. The Masters of Engineering in Energy System Engineering program provides an opportunity for cross-discipline education formore » graduates interested in a career in the energy industry. It focuses on electric power and the challenges and opportunities to develop a sustainable, reliable and resilient system that meets human needs in an increasingly sustainable manner through the use of environmentally sound energy resources and delivery. Both graduates and employers benefit from a well-trained professional workforce that is ready to hit the road running and be immediately productive in meeting these challenges, through this innovative and unique program.« less

  15. Engineering Students' Views of Corporate Social Responsibility: A Case Study from Petroleum Engineering.

    PubMed

    Smith, Jessica M; McClelland, Carrie J; Smith, Nicole M

    2017-12-01

    The mining and energy industries present unique challenges to engineers, who must navigate sometimes competing responsibilities and codes of conduct, such as personal senses of right and wrong, professional ethics codes, and their employers' corporate social responsibility (CSR) policies. Corporate social responsibility (CSR) is the current dominant framework used by industry to conceptualize firms' responsibilities to their stakeholders, yet has it plays a relatively minor role in engineering ethics education. In this article, we report on an interdisciplinary pedagogical intervention in a petroleum engineering seminar that sought to better prepare engineering undergraduate students to critically appraise the strengths and limitations of CSR as an approach to reconciling the interests of industry and communities. We find that as a result of the curricular interventions, engineering students were able to expand their knowledge of the social, rather than simply environmental and economic dimensions of CSR. They remained hesitant, however, in identifying the links between those social aspects of CSR and their actual engineering work. The study suggests that CSR may be a fruitful arena from which to illustrate the profoundly sociotechnical dimensions of the engineering challenges relevant to students' future careers.

  16. Carbon Nanotube Composites: Strongest Engineering Material Ever?

    NASA Technical Reports Server (NTRS)

    Mayeaux, Brian; Nikolaev, Pavel; Proft, William; Nicholson, Leonard S. (Technical Monitor)

    1999-01-01

    The primary goal of the carbon nanotube project at Johnson Space Center (JSC) is to fabricate structural materials with a much higher strength-to-weight ratio than any engineered material today, Single-wall nanotubes present extraordinary mechanical properties along with new challenges for materials processing. Our project includes nanotube production, characterization, purification, and incorporation into applications studies. Now is the time to move from studying individual nanotubes to applications work. Current research at JSC focuses on structural polymeric materials to attempt to lower the weight of spacecraft necessary for interplanetary missions. These nanoscale fibers present unique new challenges to composites engineers. Preliminary studies show good nanotube dispersion and wetting by the epoxy materials. Results of tensile strength tests will also be reported. Other applications of nanotubes are also of interest for energy storage, gas storage, nanoelectronics, field emission, and biomedical uses.

  17. Education News at NASA

    NASA Technical Reports Server (NTRS)

    2004-01-01

    NASA s challenging missions provide unique opportunities for engaging and educating America s youth, the next generation of explorers. Led by Chief Education Officer Dr. Adena Williams Loston, the Agency coordinates education programs for students, faculty, and institutions in order to help inspire and motivate the scientists and engineers of the future.

  18. Siemens Foundation and the STEM Challenge

    ERIC Educational Resources Information Center

    Harper-Taylor, Jeniffer

    2010-01-01

    For more than 12 years, the Siemens Foundation has found unique ways to partner with organizations to support educational initiatives in science, technology, engineering and mathematics (STEM) in the United States. Its focus is clear--to educate the next generation of innovators by supporting math and science education from grade school to grad…

  19. Model for Presenting Resources in Scholar's Portal

    ERIC Educational Resources Information Center

    Feeney, Mary; Newby, Jill

    2005-01-01

    Presenting electronic resources to users through a federated search engine introduces unique opportunities and challenges to libraries. This article reports on the decision-making tools and processes used for selecting collections of electronic resources by a project team at the University of Arizona (UA) Libraries for the Association of Research…

  20. Worksite health promotion programs in college settings

    PubMed Central

    Hill-Mey, Patricia E.; Kumpfer, Karol L.; Merrill, Ray M.; Reel, Justine; Hyatt-Neville, Beverly; Richardson, Glenn E.

    2015-01-01

    The purpose of this paper is to describe the multifaceted nature and benefits of worksite health promotion programs (WHPPs), with emphasis on the college setting. An assessment of the peer-reviewed literature was conducted of articles published since 2000. Several search engines were accessed and selected key words were used. Most studies examining WHPPs have focused on return on investment and productivity. Research that targets the softer side-benefits of health promotion programs in the workplace is less available. Although the college setting offers some advantages for implementing health promotion programs. They may also have unique challenges due to their large and diverse employee population. There is little research to show the effectiveness and unique challenges of college-based health promotion programs. PMID:25861657

  1. Designing Mission Operations for the Gravity Recovery and Interior Laboratory Mission

    NASA Technical Reports Server (NTRS)

    Havens, Glen G.; Beerer, Joseph G.

    2012-01-01

    NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission, to understand the internal structure and thermal evolution of the Moon, offered unique challenges to mission operations. From launch through end of mission, the twin GRAIL orbiters had to be operated in parallel. The journey to the Moon and into the low science orbit involved numerous maneuvers, planned on tight timelines, to ultimately place the orbiters into the required formation-flying configuration necessary. The baseline GRAIL mission is short, only 9 months in duration, but progressed quickly through seven very unique mission phases. Compressed into this short mission timeline, operations activities and maneuvers for both orbiters had to be planned and coordinated carefully. To prepare for these challenges, development of the GRAIL Mission Operations System began in 2008. Based on high heritage multi-mission operations developed by NASA's Jet Propulsion Laboratory and Lockheed Martin, the GRAIL mission operations system was adapted to meet the unique challenges posed by the GRAIL mission design. This paper describes GRAIL's system engineering development process for defining GRAIL's operations scenarios and generating requirements, tracing the evolution from operations concept through final design, implementation, and validation.

  2. How Mockups, a Key Engineering Tool, Help to Promote Science, Technology, Engineering, and Mathematics Education

    NASA Technical Reports Server (NTRS)

    McDonald, Harry E.

    2010-01-01

    The United States ranking among the world in science, technology, engineering, and mathematics (STEM) education is decreasing. To counteract this problem NASA has made it part of its mission to promote STEM education among the nation s youth. Mockups can serve as a great tool when promoting STEM education in America. The Orion Cockpit Working Group has created a new program called Students Shaping America s Next Space Craft (SSANS) to outfit the Medium Fidelity Orion Mockup. SSANS will challenge the students to come up with unique designs to represent the flight design hardware. There are two main types of project packages created by SSANS, those for high school students and those for university students. The high school projects will challenge wood shop, metal shop and pre-engineering classes. The university projects are created mainly for senior design projects and will require the students to perform finite element analysis. These projects will also challenge the undergraduate students in material selection and safety requirements. The SSANS program will help NASA in its mission to promote STEM education, and will help to shape our nations youth into the next generation of STEM leaders.

  3. Development and utilization of a bovine type I collagen microfibril model

    USDA-ARS?s Scientific Manuscript database

    The structure of fibrous collagen, a long triple helix that self-associates in a staggered array to form a matrix of fibrils, fibers and fiber bundles, makes it uniquely suitable as a scaffold for biomaterial engineering. A major challenge for this application is to stabilize collagen structure by m...

  4. Multimodal Learning Analytics and Education Data Mining: Using Computational Technologies to Measure Complex Learning Tasks

    ERIC Educational Resources Information Center

    Blikstein, Paulo; Worsley, Marcelo

    2016-01-01

    New high-frequency multimodal data collection technologies and machine learning analysis techniques could offer new insights into learning, especially when students have the opportunity to generate unique, personalized artifacts, such as computer programs, robots, and solutions engineering challenges. To date most of the work on learning analytics…

  5. International Space Station Passive Thermal Control System Analysis, Top Ten Lessons-Learned

    NASA Technical Reports Server (NTRS)

    Iovine, John

    2011-01-01

    The International Space Station (ISS) has been on-orbit for over 10 years, and there have been numerous technical challenges along the way from design to assembly to on-orbit anomalies and repairs. The Passive Thermal Control System (PTCS) management team has been a key player in successfully dealing with these challenges. The PTCS team performs thermal analysis in support of design and verification, launch and assembly constraints, integration, sustaining engineering, failure response, and model validation. This analysis is a significant body of work and provides a unique opportunity to compile a wealth of real world engineering and analysis knowledge and the corresponding lessons-learned. The analysis lessons encompass the full life cycle of flight hardware from design to on-orbit performance and sustaining engineering. These lessons can provide significant insight for new projects and programs. Key areas to be presented include thermal model fidelity, verification methods, analysis uncertainty, and operations support.

  6. Imaging challenges in biomaterials and tissue engineering

    PubMed Central

    Appel, Alyssa A.; Anastasio, Mark A.; Larson, Jeffery C.; Brey, Eric M.

    2013-01-01

    Biomaterials are employed in the fields of tissue engineering and regenerative medicine (TERM) in order to enhance the regeneration or replacement of tissue function and/or structure. The unique environments resulting from the presence of biomaterials, cells, and tissues result in distinct challenges in regards to monitoring and assessing the results of these interventions. Imaging technologies for three-dimensional (3D) analysis have been identified as a strategic priority in TERM research. Traditionally, histological and immunohistochemical techniques have been used to evaluate engineered tissues. However, these methods do not allow for an accurate volume assessment, are invasive, and do not provide information on functional status. Imaging techniques are needed that enable non-destructive, longitudinal, quantitative, and three-dimensional analysis of TERM strategies. This review focuses on evaluating the application of available imaging modalities for assessment of biomaterials and tissue in TERM applications. Included is a discussion of limitations of these techniques and identification of areas for further development. PMID:23768903

  7. Plastid biotechnology for crop production: present status and future perspectives

    PubMed Central

    Daniell, Henry

    2012-01-01

    The world population is expected to reach an estimated 9.2 billion by 2050. Therefore, food production globally has to increase by 70% in order to feed the world, while total arable land, which has reached its maximal utilization, may even decrease. Moreover, climate change adds yet another challenge to global food security. In order to feed the world in 2050, biotechnological advances in modern agriculture are essential. Plant genetic engineering, which has created a new wave of global crop production after the first green revolution, will continue to play an important role in modern agriculture to meet these challenges. Plastid genetic engineering, with several unique advantages including transgene containment, has made significant progress in the last two decades in various biotechnology applications including development of crops with high levels of resistance to insects, bacterial, fungal and viral diseases, different types of herbicides, drought, salt and cold tolerance, cytoplasmic male sterility, metabolic engineering, phytoremediation of toxic metals and production of many vaccine antigens, biopharmaceuticals and biofuels. However, useful traits should be engineered via chloroplast genomes of several major crops. This review provides insight into the current state of the art of plastid engineering in relation to agricultural production, especially for engineering agronomic traits. Understanding the bottleneck of this technology and challenges for improvement of major crops in a changing climate are discussed. PMID:21437683

  8. Examining the need & potential for biomedical engineering to strengthen health care delivery for displaced populations & victims of conflict.

    PubMed

    Nadkarni, Devika; Elhajj, Imad; Dawy, Zaher; Ghattas, Hala; Zaman, Muhammad H

    2017-01-01

    Conflict and the subsequent displacement of populations creates unique challenges in the delivery of quality health care to the affected population. Equitable access to quality care demands a multi-pronged strategy with a growing need, and role, for technological innovation to address these challenges. While there have been significant contributions towards alleviating the burden of conflict via data informatics and analytics, communication technology, and geographic information systems, little has been done within biomedical engineering. This article elaborates on the causes for gaps in biomedical innovation for refugee populations affected by conflict, tackles preconceived notions, takes stock of recent developments in promising technologies to address these challenges, and identifies tangible action items to create a stronger and sustainable pipeline for biomedical technological innovation to improve the health and well-being of an increasing group of vulnerable people around the world.

  9. Developing Smartphone Apps for Education, Outreach, Science, and Engineering

    NASA Astrophysics Data System (ADS)

    Weatherwax, A. T.; Fitzsimmons, Z.; Czajkowski, J.; Breimer, E.; Hellman, S. B.; Hunter, S.; Dematteo, J.; Savery, T.; Melsert, K.; Sneeringer, J.

    2010-12-01

    The increased popularity of mobile phone apps provide scientists with a new avenue for sharing and distributing data and knowledge with colleagues, while also providing meaningful education and outreach products for consumption by the general public. Our initial development of iPhone and Android apps centered on the distribution of exciting auroral images taken at the South Pole for education and outreach purposes. These portable platforms, with limited resources when compared to computers, presented a unique set of design and implementation challenges that we will discuss in this presentation. For example, the design must account for limited memory; screen size; processing power; battery life; and potentially high data transport costs. Some of these unique requirements created an environment that enabled undergraduate and high-school students to participate in the creation of these apps. Additionally, during development it became apparent that these apps could also serve as data analysis and engineering tools. Our presentation will further discuss our plans to use apps not only for Education and Public Outreach, but for teaching, science and engineering.

  10. The Teaching Profession and Teacher Education: Trends and Challenges in the Twenty-First Century

    ERIC Educational Resources Information Center

    Ishumi, Abel G. M.

    2013-01-01

    The paper sets out to show that teaching is among the five undeniably oldest and historically character-shaping professions in the world, the others being engineering-architecture, medicine, law, and accounting and each of these professions has a unique story in connection with its genesis and its influence on social organisation. The paper…

  11. Unique Challenges for Women of Color in STEM Transferring from Community Colleges to Universities

    ERIC Educational Resources Information Center

    Reyes, Marie-Elena

    2011-01-01

    In this article, Marie-Elena Reyes presents the issues faced by women of color in the fields of science, technology, engineering, and math (STEM) as they transfer from community colleges to universities. Community colleges offer a great potential for diversifying and increasing participation of underrepresented groups in STEM. Many women of color…

  12. Principles of Tendon Reconstruction Following Complex Trauma of the Upper Limb

    PubMed Central

    Chattopadhyay, Arhana; McGoldrick, Rory; Umansky, Elise; Chang, James

    2015-01-01

    Reconstruction of tendons following complex trauma to the upper limb presents unique clinical and research challenges. In this article, the authors review the principles guiding preoperative assessment, surgical reconstruction, and postoperative rehabilitation and management of the upper extremity. Tissue engineering approaches to address tissue shortages for tendon reconstruction are also discussed. PMID:25685101

  13. Unleashing Lessons: Sharing Stories About the Fine Art of Systems Engineering

    NASA Technical Reports Server (NTRS)

    Singer, Christopher E.

    2010-01-01

    NASA leaders have a responsibility to share their unique oral histories with junior-level employees on whom NASA's future depends. This presentation will give a few examples of how the imaginative, flexible art of systems engineering is as necessary to mission success as is the rigorous, disciplined side of engineering. Engineering space systems involves many disciplines propulsion, loads, dynamics, and so forth that are based on the foundations of scientific principles and methodology and the application of the laws of physics. The term rocket scientist is an apt term, considering that the underlying chemical properties of propellants and the subatomic properties of materials must be understood to harness the powerful energy necessary to escape Earth's gravity in machines that can withstand the stresses and forces to which they are subjected, not to mention the harsh space environments in which they must work. This is a simplistic, yet illustrative, explanation of the scientific side of the engineer s challenge. Bringing together these individual parts into a solid system goes beyond the science of engineering to employ the art of systems engineering. Systems engineers are known for their ability to integrate various solutions to meet or exceed challenging requirements. As the old adage goes, measure twice and cut once. The act of measuring is balancing rigid, inflexible requirements with creative compromises to attain the optimum solution to the challenge of space flight. Then, we cut out those answers that are too risky, expensive, dangerous, and so forth. The process of sharing stories about the little-discussed art of engineering, also known as the art of compromise, will equip the workforce to subjectively judge the best right answer from among the many presented, while objectively integrating the various piece parts into a unified whole.

  14. Toward Perovskite Solar Cell Commercialization: A Perspective and Research Roadmap Based on Interfacial Engineering.

    PubMed

    Rajagopal, Adharsh; Yao, Kai; Jen, Alex K-Y

    2018-06-08

    High-efficiency and low-cost perovskite solar cells (PVKSCs) are an ideal candidate for addressing the scalability challenge of solar-based renewable energy. The dynamically evolving research field of PVKSCs has made immense progress in solving inherent challenges and capitalizing on their unique structure-property-processing-performance traits. This review offers a unique outlook on the paths toward commercialization of PVKSCs from the interfacial engineering perspective, relevant to both specialists and nonspecialists in the field through a brief introduction of the background of the field, current state-of-the-art evolution, and future research prospects. The multifaceted role of interfaces in facilitating PVKSC development is explained. Beneficial impacts of diverse charge-transporting materials and interfacial modifications are summarized. In addition, the role of interfaces in improving efficiency and stability for all emerging areas of PVKSC design are also evaluated. The authors' integral contributions in this area are highlighted on all fronts. Finally, future research opportunities for interfacial material development and applications along with scalability-durability-sustainability considerations pivotal for facilitating laboratory to industry translation are presented. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. An Overview of the Thermal Challenges of Designing Microgravity Furnaces

    NASA Technical Reports Server (NTRS)

    Westra, Douglas G.

    2001-01-01

    Marshall Space Flight Center is involved in a wide variety of microgravity projects that require furnaces, with hot zone temperatures ranging from 300 C to 2300 C, requirements for gradient processing and rapid quench, and both semi-conductor and metal materials. On these types of projects, the thermal engineer is a key player in the design process. Microgravity furnaces present unique challenges to the thermal designer. One challenge is designing a sample containment assembly that achieves dual containment, yet allows a high radial heat flux. Another challenge is providing a high axial gradient but a very low radial gradient. These furnaces also present unique challenges to the thermal analyst. First, there are several orders of magnitude difference in the size of the thermal 'conductors' between various parts of the model. A second challenge is providing high fidelity in the sample model, and connecting the sample with the rest of the furnace model, yet maintaining some sanity in the number of total nodes in the model. The purpose of this paper is to present an overview of the challenges involved in designing and analyzing microgravity furnaces and how some of these challenges have been overcome. The thermal analysis tools presently used to analyze microgravity furnaces and will be listed. Challenges for the future and a description of future analysis tools will be given.

  16. Synthetic biology of cyanobacteria: unique challenges and opportunities

    PubMed Central

    Berla, Bertram M.; Saha, Rajib; Immethun, Cheryl M.; Maranas, Costas D.; Moon, Tae Seok; Pakrasi, Himadri B.

    2013-01-01

    Photosynthetic organisms, and especially cyanobacteria, hold great promise as sources of renewably-produced fuels, bulk and specialty chemicals, and nutritional products. Synthetic biology tools can help unlock cyanobacteria's potential for these functions, but unfortunately tool development for these organisms has lagged behind that for S. cerevisiae and E. coli. While these organisms may in many cases be more difficult to work with as “chassis” strains for synthetic biology than certain heterotrophs, the unique advantages of autotrophs in biotechnology applications as well as the scientific importance of improved understanding of photosynthesis warrant the development of these systems into something akin to a “green E. coli.” In this review, we highlight unique challenges and opportunities for development of synthetic biology approaches in cyanobacteria. We review classical and recently developed methods for constructing targeted mutants in various cyanobacterial strains, and offer perspective on what genetic tools might most greatly expand the ability to engineer new functions in such strains. Similarly, we review what genetic parts are most needed for the development of cyanobacterial synthetic biology. Finally, we highlight recent methods to construct genome-scale models of cyanobacterial metabolism and to use those models to measure properties of autotrophic metabolism. Throughout this paper, we discuss some of the unique challenges of a diurnal, autotrophic lifestyle along with how the development of synthetic biology and biotechnology in cyanobacteria must fit within those constraints. PMID:24009604

  17. Protein engineering in designing tailored enzymes and microorganisms for biofuels production

    PubMed Central

    Wen, Fei; Nair, Nikhil U; Zhao, Huimin

    2009-01-01

    Summary Lignocellulosic biofuels represent a sustainable, renewable, and the only foreseeable alternative energy source to transportation fossil fuels. However, the recalcitrant nature of lignocellulose poses technical hurdles to an economically viable biorefinery. Low enzymatic hydrolysis efficiency and low productivity, yield, and titer of biofuels are among the top cost contributors. Protein engineering has been used to improve the performances of lignocellulose-degrading enzymes, as well as proteins involved in biofuel synthesis pathways. Unlike its great success seen in other industrial applications, protein engineering has achieved only modest results in improving the lignocellulose-to-biofuels efficiency. This review will discuss the unique challenges that protein engineering faces in the process of converting lignocellulose to biofuels and how they are addressed by recent advances in this field. PMID:19660930

  18. Characteristics of Israeli women studying nursing compared to women studying education and engineering.

    PubMed

    Horn, H; Holzemer, W L

    1991-11-01

    This study examined the demographic characteristics, vocational personality, and sex-role orientation of Israeli women studying nursing compared to women studying education and engineering. The convenience sample was 176 university students. The instrument included a demographic inventory, Holland's Self-Directed Search (SDS) questionnaire, and the Sex-Role Orientation Attitude questionnaire. Nursing and education students had Holland's "social" personality types and engineering students were more "realistic" or "investigative". Nursing and engineering students were significantly more feminist in their orientation than education majors. Nursing students were nontraditional women who had traditional family backgrounds, yet were nontraditional in their feminist orientation. With nursing's move into colleges and universities, the need for academically qualified applicants has intensified. Developing a better understanding of the unique nature of nursing and nursing students is a challenge.

  19. Advantages and challenges offered by biofunctional core-shell fiber systems for tissue engineering and drug delivery.

    PubMed

    Sperling, Laura E; Reis, Karina P; Pranke, Patricia; Wendorff, Joachim H

    2016-08-01

    Whereas highly porous scaffolds composed of electrospun nanofibers can mimick major features of the extracellular matrix in tissue engineering, they lack the ability to incorporate and release biocompounds (drugs, growth factors) safely in a controlled way. Here, electrospun core-shell fibers (core made from water and aqueous solutions of hydrophilic polymers and the shell from materials with well-defined release mechanisms) offer unique advantages in comparison with those that have helped make porous nanofibrillar scaffolds highly successful in tissue engineering. This review considers the preparation and biofunctionalization of such core-shell fibers as well as applications in various areas, including neural, vascular, cardiac, cartilage and bone tissue engineering, and touches on the topic of clinical trials. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Present capabilities and future requirements for computer-aided geometric modeling in the design and manufacture of gas turbine

    NASA Technical Reports Server (NTRS)

    Caille, E.; Propen, M.; Hoffman, A.

    1984-01-01

    Gas turbine engine design requires the ability to rapidly develop complex structures which are subject to severe thermal and mechanical operating loads. As in all facets of the aerospace industry, engine designs are constantly driving towards increased performance, higher temperatures, higher speeds, and lower weight. The ability to address such requirements in a relatively short time frame has resulted in a major thrust towards integrated design/analysis/manufacturing systems. These computer driven graphics systems represent a unique challenge, with major payback opportunities if properly conceived, implemented, and applied.

  1. Engineered Graphene Materials: Synthesis and Applications for Polymer Electrolyte Membrane Fuel Cells.

    PubMed

    He, Daping; Tang, Haolin; Kou, Zongkui; Pan, Mu; Sun, Xueliang; Zhang, Jiujun; Mu, Shichun

    2017-05-01

    Engineered graphene materials (EGMs) with unique structures and properties have been incorporated into various components of polymer electrolyte membrane fuel cells (PEMFCs) such as electrode, membrane, and bipolar plates to achieve enhanced performances in terms of electrical conductivity, mechanical durability, corrosion resistance, and electrochemical surface area. This research news article provides an overview of the recent development in EGMs and EGM-based PEMFCs with a focus on the effects of EGMs on PEMFC performance when they are incorporated into different components of PEMFCs. The challenges of EGMs for practical PEMFC applications in terms of production scale, stability, conductivity, and coupling capability with other materials are also discussed and the corresponding measures and future research trends to overcome such challenges are proposed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Advanced Noise Abatement Procedures for a Supersonic Business Jet

    NASA Technical Reports Server (NTRS)

    Berton, Jeffrey J.; Jones, Scott M.; Seidel, Jonathan A.; Huff, Dennis L.

    2017-01-01

    Supersonic civil aircraft present a unique noise certification challenge. High specific thrust required for supersonic cruise results in high engine exhaust velocity and high levels of jet noise during takeoff. Aerodynamics of thin, low-aspect-ratio wings equipped with relatively simple flap systems deepen the challenge. Advanced noise abatement procedures have been proposed for supersonic aircraft. These procedures promise to reduce airport noise, but they may require departures from normal reference procedures defined in noise regulations. The subject of this report is a takeoff performance and noise assessment of a notional supersonic business jet. Analytical models of an airframe and a supersonic engine derived from a contemporary subsonic turbofan core are developed. These models are used to predict takeoff trajectories and noise. Results indicate advanced noise abatement takeoff procedures are helpful in reducing noise along lateral sidelines.

  3. Stem cell bioprinting for applications in regenerative medicine.

    PubMed

    Tricomi, Brad J; Dias, Andrew D; Corr, David T

    2016-11-01

    Many regenerative medicine applications seek to harness the biologic power of stem cells in architecturally complex scaffolds or microenvironments. Traditional tissue engineering methods cannot create such intricate structures, nor can they precisely control cellular position or spatial distribution. These limitations have spurred advances in the field of bioprinting, aimed to satisfy these structural and compositional demands. Bioprinting can be defined as the programmed deposition of cells or other biologics, often with accompanying biomaterials. In this concise review, we focus on recent advances in stem cell bioprinting, including performance, utility, and applications in regenerative medicine. More specifically, this review explores the capability of bioprinting to direct stem cell fate, engineer tissue(s), and create functional vascular networks. Furthermore, the unique challenges and concerns related to bioprinting living stem cells, such as viability and maintaining multi- or pluripotency, are discussed. The regenerative capacity of stem cells, when combined with the structural/compositional control afforded by bioprinting, provides a unique and powerful tool to address the complex demands of tissue engineering and regenerative medicine applications. © 2016 New York Academy of Sciences.

  4. Engineering on the straight and narrow: the mechanics of nanofibrous assemblies for fiber-reinforced tissue regeneration.

    PubMed

    Mauck, Robert L; Baker, Brendon M; Nerurkar, Nandan L; Burdick, Jason A; Li, Wan-Ju; Tuan, Rocky S; Elliott, Dawn M

    2009-06-01

    Tissue engineering of fibrous tissues of the musculoskeletal system represents a considerable challenge because of the complex architecture and mechanical properties of the component structures. Natural healing processes in these dense tissues are limited as a result of the mechanically challenging environment of the damaged tissue and the hypocellularity and avascular nature of the extracellular matrix. When healing does occur, the ordered structure of the native tissue is replaced with a disorganized fibrous scar with inferior mechanical properties, engendering sites that are prone to re-injury. To address the engineering of such tissues, we and others have adopted a structurally motivated approach based on organized nanofibrous assemblies. These scaffolds are composed of ultrafine polymeric fibers that can be fabricated in such a way to recreate the structural anisotropy typical of fiber-reinforced tissues. This straight-and-narrow topography not only provides tailored mechanical properties, but also serves as a 3D biomimetic micropattern for directed tissue formation. This review describes the underlying technology of nanofiber production and focuses specifically on the mechanical evaluation and theoretical modeling of these structures as it relates to native tissue structure and function. Applying the same mechanical framework for understanding native and engineered fiber-reinforced tissues provides a functional method for evaluating the utility and maturation of these unique engineered constructs. We further describe several case examples where these principles have been put to test, and discuss the remaining challenges and opportunities in forwarding this technology toward clinical implementation.

  5. Engineering on the Straight and Narrow: The Mechanics of Nanofibrous Assemblies for Fiber-Reinforced Tissue Regeneration

    PubMed Central

    Baker, Brendon M.; Nerurkar, Nandan L.; Burdick, Jason A.; Li, Wan-Ju; Tuan, Rocky S.; Elliott, Dawn M.

    2009-01-01

    Tissue engineering of fibrous tissues of the musculoskeletal system represents a considerable challenge because of the complex architecture and mechanical properties of the component structures. Natural healing processes in these dense tissues are limited as a result of the mechanically challenging environment of the damaged tissue and the hypocellularity and avascular nature of the extracellular matrix. When healing does occur, the ordered structure of the native tissue is replaced with a disorganized fibrous scar with inferior mechanical properties, engendering sites that are prone to re-injury. To address the engineering of such tissues, we and others have adopted a structurally motivated approach based on organized nanofibrous assemblies. These scaffolds are composed of ultrafine polymeric fibers that can be fabricated in such a way to recreate the structural anisotropy typical of fiber-reinforced tissues. This straight-and-narrow topography not only provides tailored mechanical properties, but also serves as a 3D biomimetic micropattern for directed tissue formation. This review describes the underlying technology of nanofiber production and focuses specifically on the mechanical evaluation and theoretical modeling of these structures as it relates to native tissue structure and function. Applying the same mechanical framework for understanding native and engineered fiber-reinforced tissues provides a functional method for evaluating the utility and maturation of these unique engineered constructs. We further describe several case examples where these principles have been put to test, and discuss the remaining challenges and opportunities in forwarding this technology toward clinical implementation. PMID:19207040

  6. The engineering options for mitigating the climate impacts of aviation.

    PubMed

    Williams, Victoria

    2007-12-15

    Aviation is a growing contributor to climate change, with unique impacts due to the altitude of emissions. If existing traffic growth rates continue, radical engineering solutions will be required to prevent aviation becoming one of the dominant contributors to climate change. This paper reviews the engineering options for mitigating the climate impacts of aviation using aircraft and airspace technologies. These options include not only improvements in fuel efficiency, which would reduce carbon dioxide (CO2) emissions, but also measures to reduce non-CO2 impacts including the formation of persistent contrails. Integrated solutions to optimize environmental performance will require changes to airframes, engines, avionics, air traffic control systems and airspace design. While market-based measures, such as offset schemes and emissions trading, receive growing attention, this paper sets out the crucial role of engineering in the challenge to develop a 'green air traffic system'.

  7. Cell engineering: spearheading the next generation in healthcare.

    PubMed

    Jayasinghe, Suwan N

    2008-09-01

    Manipulating living mammalian cells present fascinating possibilities for a plethora of applications within our healthcare. These imply several possibilities in tissue engineering and regenerative medicine, to those of a therapeutic nature. The physical sciences are increasingly playing a pivotal role in this endeavour by both advancing existing cell engineering technology and pioneering new protocols for the creation of biologically viable structures. In this paper, the author introduces several direct needle/channel/orifice-based cell engineering protocols, currently undergoing intense investigation for a whole host of bio-applications. Hence, each protocol's advantages and disadvantages are clearly identified, whilst recognizing their future biological and engineering challenges. In conclusion, a few selected biotechnological applications present possibilities where these protocols could undergo focused exploration. Successful development of these bio-protocols sees the emergence of unique future strategies within a clinical environment having far-reaching consequences for our healthcare.

  8. 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.

  9. Integrating Safety with Science,Technology and Innovation at Los Alamos National Laboratory

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

    Rich, Bethany M

    2012-04-02

    The mission of Los Alamos National Laboratory (LANL) is to develop and apply science, technology and engineering solutions to ensure the safety, security, and reliability of the U.S. nuclear deterrent; reduce global threats; and solve emerging national security challenges. The most important responsibility is to direct and conduct efforts to meet the mission with an emphasis on safety, security, and quality. In this article, LANL Environmental, Safety, and Health (ESH) trainers discuss how their application and use of a kinetic learning module (learn by doing) with a unique fall arrest system is helping to address one the most common industrialmore » safety challenges: slips and falls. A unique integration of Human Performance Improvement (HPI), Behavior Based Safety (BBS) and elements of the Voluntary Protection Program (VPP) combined with an interactive simulator experience is being used to address slip and fall events at Los Alamos.« less

  10. A Geology Sampling System for Small Bodies

    NASA Technical Reports Server (NTRS)

    Hood, A. D.; Naids, A. J.; Graff, T.; Abell, P.

    2015-01-01

    Human exploration of Small Bodies is being investigated as a precursor to a Mars surface mission. Asteroids, comets, dwarf planets, and the moons of Mars all fall into this Small Bodies category and some are being discussed as potential mission tar-gets. Obtaining geological samples for return to Earth will be a major objective for any mission to a Small Body. Currently the knowledge base for geology sampling in microgravity is in its infancy. Furthermore, humans interacting with non-engineered surfaces in a microgravity environment poses unique challenges. In preparation for such missions, a team at the National Aeronautics and Space Administration (NASA) John-son Space Center (JSC) has been working to gain experience on how to safely obtain numerous sample types in such an environment. This abstract briefly summarizes the type of samples the science community is interested in, discusses an integrated geology sampling solution, and highlights some of the unique challenges associated with this type of exploration.

  11. Nanomedicine applications in orthopedic medicine: state of the art

    PubMed Central

    Mazaheri, Mozhdeh; Eslahi, Niloofar; Ordikhani, Farideh; Tamjid, Elnaz; Simchi, Abdolreza

    2015-01-01

    The technological and clinical need for orthopedic replacement materials has led to significant advances in the field of nanomedicine, which embraces the breadth of nanotechnology from pharmacological agents and surface modification through to regulation and toxicology. A variety of nanostructures with unique chemical, physical, and biological properties have been engineered to improve the functionality and reliability of implantable medical devices. However, mimicking living bone tissue is still a challenge. The scope of this review is to highlight the most recent accomplishments and trends in designing nanomaterials and their applications in orthopedics with an outline on future directions and challenges. PMID:26451110

  12. Nanomedicine applications in orthopedic medicine: state of the art.

    PubMed

    Mazaheri, Mozhdeh; Eslahi, Niloofar; Ordikhani, Farideh; Tamjid, Elnaz; Simchi, Abdolreza

    2015-01-01

    The technological and clinical need for orthopedic replacement materials has led to significant advances in the field of nanomedicine, which embraces the breadth of nanotechnology from pharmacological agents and surface modification through to regulation and toxicology. A variety of nanostructures with unique chemical, physical, and biological properties have been engineered to improve the functionality and reliability of implantable medical devices. However, mimicking living bone tissue is still a challenge. The scope of this review is to highlight the most recent accomplishments and trends in designing nanomaterials and their applications in orthopedics with an outline on future directions and challenges.

  13. Case studies of pre-engineered and manufactured sound isolation rooms for music practice and radio broadcast

    NASA Astrophysics Data System (ADS)

    Probst, Ron N.; Rypka, Dann

    2005-09-01

    Pre-engineered and manufactured sound isolation rooms were developed to ensure guaranteed sound isolation while offering the unique ability to be disassembled and relocated without loss of acoustic performance. Case studies of pre-engineered sound isolation rooms used for music practice and various radio broadcast purposes are highlighted. Three prominent universities wrestle with the challenges of growth and expansion while responding to the specialized acoustic requirements of these spaces. Reduced state funding for universities requires close examination of all options while ensuring sound isolation requirements are achieved. Changing curriculum, renovation, and new construction make pre-engineered and manufactured rooms with guaranteed acoustical performance good investments now and for the future. An added benefit is the optional integration of active acoustics to provide simulations of other spaces or venues along with the benefit of sound isolation.

  14. X-33 Attitude Control Using the XRS-2200 Linear Aerospike Engine

    NASA Technical Reports Server (NTRS)

    Hall, Charles E.; Panossian, Hagop V.

    1999-01-01

    The Vehicle Control Systems Team at Marshall Space Flight Center, Structures and Dynamics Laboratory, Guidance and Control Systems Division is designing, under a cooperative agreement with Lockheed Martin Skunkworks, the Ascent, Transition, and Entry flight attitude control systems for the X-33 experimental vehicle. Test flights, while suborbital, will achieve sufficient altitudes and Mach numbers to test Single Stage To Orbit, Reusable Launch Vehicle technologies. Ascent flight control phase, the focus of this paper, begins at liftoff and ends at linear aerospike main engine cutoff (MECO). The X-33 attitude control system design is confronted by a myriad of design challenges: a short design cycle, the X-33 incremental test philosophy, the concurrent design philosophy chosen for the X-33 program, and the fact that the attitude control system design is, as usual, closely linked to many other subsystems and must deal with constraints and requirements from these subsystems. Additionally, however, and of special interest, the use of the linear aerospike engine is a departure from the gimbaled engines traditionally used for thrust vector control (TVC) in launch vehicles and poses certain design challenges. This paper discusses the unique problem of designing the X-33 attitude control system with the linear aerospike engine, requirements development, modeling and analyses that verify the design.

  15. Cleared for Launch - Lessons Learned from the OSIRIS-REx System Requirements Verification Program

    NASA Technical Reports Server (NTRS)

    Stevens, Craig; Adams, Angela; Williams, Bradley; Goodloe, Colby

    2017-01-01

    Requirements verification of a large flight system is a challenge. It is especially challenging for engineers taking on their first role in space systems engineering. This paper describes our approach to verification of the Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) system requirements. It also captures lessons learned along the way from developing systems engineers embroiled in this process. We begin with an overview of the mission and science objectives as well as the project requirements verification program strategy. A description of the requirements flow down is presented including our implementation for managing the thousands of program and element level requirements and associated verification data. We discuss both successes and methods to improve the managing of this data across multiple organizational interfaces. Our approach to verifying system requirements at multiple levels of assembly is presented using examples from our work at instrument, spacecraft, and ground segment levels. We include a discussion of system end-to-end testing limitations and their impacts to the verification program. Finally, we describe lessons learned that are applicable to all emerging space systems engineers using our unique perspectives across multiple organizations of a large NASA program.

  16. Characterizing Distributed Concurrent Engineering Teams: A Descriptive Framework for Aerospace Concurrent Engineering Design Teams

    NASA Technical Reports Server (NTRS)

    Chattopadhyay, Debarati; Hihn, Jairus; Warfield, Keith

    2011-01-01

    As aerospace missions grow larger and more technically complex in the face of ever tighter budgets, it will become increasingly important to use concurrent engineering methods in the development of early conceptual designs because of their ability to facilitate rapid assessments and trades in a cost-efficient manner. To successfully accomplish these complex missions with limited funding, it is also essential to effectively leverage the strengths of individuals and teams across government, industry, academia, and international agencies by increased cooperation between organizations. As a result, the existing concurrent engineering teams will need to increasingly engage in distributed collaborative concurrent design. This paper is an extension of a recent white paper written by the Concurrent Engineering Working Group, which details the unique challenges of distributed collaborative concurrent engineering. This paper includes a short history of aerospace concurrent engineering, and defines the terms 'concurrent', 'collaborative' and 'distributed' in the context of aerospace concurrent engineering. In addition, a model for the levels of complexity of concurrent engineering teams is presented to provide a way to conceptualize information and data flow within these types of teams.

  17. Teaching ethics in engineering education through historical analysis.

    PubMed

    Billington, David P

    2006-04-01

    The goal of this paper is to stress the significance of ethics for engineering education and to illustrate how it can be brought into the mainstream of higher education in a natural way that is integrated with the teaching objectives of enriching the core meaning of engineering. Everyone will agree that the practicing engineer should be virtuous, should be a good colleague, and should use professional understanding for the common good. But these injunctions to virtue do not reach closely enough the ethic of the engineer as engineer, as someone acting in a uniquely engineering situation, and it is to such conditions that I wish to speak through a set of specific examples from recent history. I shall briefly refer to four controversies between engineers. Then, in some detail I shall narrate three historical cases that directly involve the actions of one engineer, and finally I would like to address some common contemporary issues. The first section, Engineering Ethics and the History of Innovation, includes four cases involving professional controversy. Each controversy sets two people against each other in disputes over who invented the telegraph, the radio, the automobile, and the airplane. In each dispute, it is possible to identify ethical and unethical behavior or ambiguous ethical behavior that serves as a basis for educational discussion. The first two historical cases described in "Crises and the Engineer" involve the primary closure dam systems in The Netherlands, each one the result of the actions of one engineer. The third tells of an American engineer who took his political boss, a big city mayor, to court over the illegal use of a watershed. The challenges these engineers faced required, in the deepest sense, a commitment to ethical behavior that is unique to engineering and instructive to our students. Finally, the cases in "Professors and Comparative Critical Analysis" illuminate the behavior of engineers in the design of structures and also how professors can make public criticisms of designs that seem wasteful.

  18. CHEMO/mechanical energy conversiona via supramolecular self-assembly

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

    Lynn, David G.; Conticello, Vincent

    With the assembly codes for protein/peptide self-assembly sufficiently developed to control these phases, we are positioned to address critical requirements for generating unique self-propagating functional assemblies such as chemical batteries and engines that can be used to extend the capability of living cells. These integrative functional assemblies can then be used within cells to create new functions that will address the world’s energy challenges.

  19. Chromatin regulation at the frontier of synthetic biology.

    PubMed

    Keung, Albert J; Joung, J Keith; Khalil, Ahmad S; Collins, James J

    2015-03-01

    As synthetic biology approaches are extended to diverse applications throughout medicine, biotechnology and basic biological research, there is an increasing need to engineer yeast, plant and mammalian cells. Eukaryotic genomes are regulated by the diverse biochemical and biophysical states of chromatin, which brings distinct challenges, as well as opportunities, over applications in bacteria. Recent synthetic approaches, including 'epigenome editing', have allowed the direct and functional dissection of many aspects of physiological chromatin regulation. These studies lay the foundation for biomedical and biotechnological engineering applications that could take advantage of the unique combinatorial and spatiotemporal layers of chromatin regulation to create synthetic systems of unprecedented sophistication.

  20. An Internship Model for Culturally Relevant Success for Native American High School Students

    NASA Astrophysics Data System (ADS)

    Nall, J.; Graham, E. M.

    2004-12-01

    Culturally relevant educational practices can be challenging to implement in the workplace. In an effort to support equity in access to undergraduate internship opportunities for Native American students, NASA Jet Propulsion Laboratory's (JPL) Education Office, Minority Education Initiatives offers a unique approach to supporting students from Native American reservation high schools in Washington State to participate in eight-week technical (Science, Technology, Engineering and Mathematics related) summer internships. This talk will address the Alliance for Learning and Vision for Americans (ALVA) program's twelve years of success based on four programmatic principals, annual review and the critical support of scientists and engineers.

  1. Chromatin regulation at the frontier of synthetic biology

    PubMed Central

    Keung, Albert J.; Joung, J. Keith; Khalil, Ahmad S.; Collins, James J.

    2016-01-01

    As synthetic biology approaches are extended to diverse applications throughout medicine, biotechnology and basic biological research, there is an increasing need to engineer yeast, plant and mammalian cells. Eukaryotic genomes are regulated by the diverse biochemical and biophysical states of chromatin, which brings distinct challenges, as well as opportunities, over applications in bacteria. Recent synthetic approaches, including `epigenome editing', have allowed the direct and functional dissection of many aspects of physiological chromatin regulation. These studies lay the foundation for biomedical and biotechnological engineering applications that could take advantage of the unique combinatorial and spatiotemporal layers of chromatin regulation to create synthetic systems of unprecedented sophistication. PMID:25668787

  2. The NDCX-II engineering design

    NASA Astrophysics Data System (ADS)

    Waldron, W. L.; Abraham, W. J.; Arbelaez, D.; Friedman, A.; Galvin, J. E.; Gilson, E. P.; Greenway, W. G.; Grote, D. P.; Jung, J.-Y.; Kwan, J. W.; Leitner, M.; Lidia, S. M.; Lipton, T. M.; Reginato, L. L.; Regis, M. J.; Roy, P. K.; Sharp, W. M.; Stettler, M. W.; Takakuwa, J. H.; Volmering, J.; Vytla, V. K.

    2014-01-01

    The Neutralized Drift Compression Experiment (NDCX-II) is a user facility located at Lawrence Berkeley National Laboratory which is uniquely designed for ion-beam-driven high energy density laboratory physics and heavy ion fusion research. Construction was completed in March 2012 and the facility is now in the commissioning phase. A significant amount of engineering was carried out in order to meet the performance parameters required for a wide range of target heating experiments while making the most cost-effective use of high-value hardware available from a decommissioned high current electron induction accelerator. The technical challenges and design of this new ion induction accelerator facility are described.

  3. Generation SMH (shaking my head): Work-Life Balance and Generational Realities

    NASA Astrophysics Data System (ADS)

    Jones, M. B.

    2012-12-01

    Many Federal Agencies have 'workforce development' programs that focus on preparing the next generation of scientists and engineers at the graduate and undergraduate level. Several of the science Agencies (e.g., NASA, NOAA, EPA, etc.), have programs that support students in many of the diverse disciplines that are unique to those Agency missions. While financial support certainly is critical to assist students in the STEM and other fields, professional development is just as important to equip students with a balanced arsenal of tactics to be successful professionals in the STEM workforce of today. Finding life balance as one moves through a STEM career path poses unique challenges that require a certain skill set that is not always intuitive. Some of those challenges include: selecting grad or post doc positions (negotiating to a family's advantage); balancing work and family commitments; and dealing with employer/advisor perceptions and expectations. For current and future generations in STEM, many of the above mentioned challenges require additional skill in negotiating interactions with individuals from other generations. Understanding perceptions and managing expectations are learnable skills that do not necessarily come with project funding.

  4. SHARP's systems engineering challenge: rectifying integrated product team requirements with performance issues in an evolutionary spiral development acquisition

    NASA Astrophysics Data System (ADS)

    Kuehl, C. Stephen

    2003-08-01

    Completing its final development and early deployment on the Navy's multi-role aircraft, the F/A-18 E/F Super Hornet, the SHAred Reconnaissance Pod (SHARP) provides the war fighter with the latest digital tactical reconnaissance (TAC Recce) Electro-Optical/Infrared (EO/IR) sensor system. The SHARP program is an evolutionary acquisition that used a spiral development process across a prototype development phase tightly coupled into overlapping Engineering and Manufacturing Development (EMD) and Low Rate Initial Production (LRIP) phases. Under a tight budget environment with a highly compressed schedule, SHARP challenged traditional acquisition strategies and systems engineering (SE) processes. Adopting tailored state-of-the-art systems engineering process models allowd the SHARP program to overcome the technical knowledge transition challenges imposed by a compressed program schedule. The program's original goal was the deployment of digital TAC Recce mission capabilities to the fleet customer by summer of 2003. Hardware and software integration technical challenges resulted from requirements definition and analysis activities performed across a government-industry led Integrated Product Team (IPT) involving Navy engineering and test sites, Boeing, and RTSC-EPS (with its subcontracted hardware and government furnished equipment vendors). Requirements development from a bottoms-up approach was adopted using an electronic requirements capture environment to clarify and establish the SHARP EMD product baseline specifications as relevant technical data became available. Applying Earned-Value Management (EVM) against an Integrated Master Schedule (IMS) resulted in efficiently managing SE task assignments and product deliveries in a dynamically evolving customer requirements environment. Application of Six Sigma improvement methodologies resulted in the uncovering of root causes of errors in wiring interconnectivity drawings, pod manufacturing processes, and avionics requirements specifications. Utilizing the draft NAVAIR SE guideline handbook and the ANSI/EIA-632 standard: Processes for Engineering a System, a systems engineering tailored process approach was adopted for the accelerated SHARP EMD prgram. Tailoring SE processes in this accelerated product delivery environment provided unique opportunities to be technically creative in the establishment of a product performance baseline. This paper provides an historical overview of the systems engineering activities spanning the prototype phase through the EMD SHARP program phase, the performance requirement capture activities and refinement process challenges, and what SE process improvements can be applied to future SHARP-like programs adopting a compressed, evolutionary spiral development acquisition paradigm.

  5. Rehabilitation engineering training for the future: influence of trends in academics, technology, and health reform.

    PubMed

    Winters, J M

    1995-01-01

    A perspective is offered on rehabilitation engineering educational strategies, with a focus on the bachelor's and master's levels. Ongoing changes in engineering education are summarized, especially as related to the integration of design and computers throughout the curriculum; most positively affect rehabilitation engineering training. The challenge of identifying long-term "niches" for rehabilitation engineers within a changing rehabilitation service delivery process is addressed. Five key training components are identified and developed: core science and engineering knowledge, synthesized open-ended problem-solving skill development, hands-on design experience, rehabilitation breadth exposure, and a clinical internship. Two unique abilities are identified that help demarcate the engineer from other providers: open-ended problem-solving skills that include quantitative analysis when appropriate, and objective quantitative evaluation of human performance. Educational strategies for developing these abilities are addressed. Finally, a case is made for training "hybrid" engineers/therapists, in particular bachelor-level engineers who go directly to graduate school to become certified orthotists/prosthetists or physical/occupational therapists, pass the RESNA-sponsored assistive technology service provision exam along the way, then later in life obtain a professional engineer's license and an engineering master's degree.

  6. Socio-ethical education in nanotechnology engineering programmes: a case study in Malaysia.

    PubMed

    Balakrishnan, Balamuralithara; Er, Pek Hoon; Visvanathan, Punita

    2013-09-01

    The unique properties of nanotechnology have made nanotechnology education and its related subjects increasingly important not only for students but for mankind at large. This particular technology brings educators to work together to prepare and produce competent engineers and scientists for this field. One of the key challenges in nanotechnology engineering is to produce graduate students who are not only competent in technical knowledge but possess the necessary attitude and awareness toward the social and ethical issues related to nanotechnology. In this paper, a research model has been developed to assess Malaysian nanotechnology engineering students' attitudes and whether their perspectives have attained the necessary objectives of ethical education throughout their programme of study. The findings from this investigation show that socio ethical education has a strong influence on the students' knowledge, skills and attitudes pertaining to socio ethical issues related to nanotechnology.

  7. Using Self-Determination Theory to build communities of support to aid in the retention of women in engineering

    NASA Astrophysics Data System (ADS)

    Dell, Elizabeth M.; Verhoeven, Yen; Christman, Jeanne W.; Garrick, Robert D.

    2018-05-01

    Diverse perspectives are required to address the technological problems facing our world. Although women perform as well as their male counterparts in math and science prior to entering college, the numbers of women students entering and completing engineering programmes are far below their representation in the workforce. This paper reports on a qualitative, multiyear study of the experiences of women students in an Engineering Technology programme. The project addressed some of the unique, fundamental challenges that female students face within their programmes, and the authors describe a programmatic framework based on Self-Determination Theory as an intervention for the recruitment and retention of female engineering students. Data from focus groups and interviews show how students were supported in their undergraduate experiences and how inclusive learning environments are needed to further improve outcomes. Conceptual issues and methodological considerations of our outcomes are presented.

  8. Turbomachinery Course

    NASA Technical Reports Server (NTRS)

    Stinson, Henry; Turner, James (Technical Monitor)

    2002-01-01

    In this viewgraph presentation, information and diagrams are provided on rocket engine turbopumps. These turbomachines are highly complex and have several unique features: (1) They are generally very high power density machines; (2) They experience high fluid dynamic loads; (3) They are exposed to severe thermal shocks in terms of rapid starts and stops and extremely high heat transfer coefficients; (4) They have stringent suction performance requirements to minimize tank weight; (5) Their working fluids significantly impact the design: oxidizers are generally explosive, they afford almost no lubrication for bearings and seals, some fuels can degrade material properties, cryogenics result in severe thermal gradients; (6) Their life requirements are short relative to other turbomachines in that there are hundreds of cycles and a few hours of operation for reusable systems. The design of rocket engine turbomachines is a systems engineering challenge because multiple engineering disciplines must be integrated to deal with issues pertaining to stress, structural dynamics, hydrodynamics, aerodynamics, thermodynamics, and materials and process selection.

  9. Clinical Immersion: An Approach for Fostering Cross-disciplinary Communication and Innovation in Nursing and Engineering Students.

    PubMed

    Geist, Melissa J; Sanders, Robby; Harris, Kevin; Arce-Trigatti, Andrea; Hitchcock-Cass, Cary

    2018-05-24

    A faculty team from nursing and chemical engineering developed a course that brought together students from each discipline for cross-disciplinary, team-based clinical immersion and collaboration. Health care processes and devices are rapidly changing, and nurses are uniquely positioned to be bedside innovators to improve patient care delivery. During each clinical immersion, the student teams rotated through various hospital units where they identified problems and worked together in the university's makerspace (iMaker Space) to design and build prototypes to improve health outcomes. Data from the Critical thinking Assessment Test provided evidence of gains in critical-thinking and problem-solving skills, while the problems identified in the clinical setting and prototypes developed demonstrated the impact of bringing nursing and engineering students together to design innovations. When challenged to identify authentic problems during their clinical immersion, the teams of nursing and engineering students proposed creative solutions and developed commercially viable prototypes.

  10. Extracellular-Matrix-Based and Arg-Gly-Asp–Modified Photopolymerizing Hydrogels for Cartilage Tissue Engineering

    PubMed Central

    Kim, Hwan D.; Heo, Jiseung; Hwang, Yongsung; Kwak, Seon-Yeong; Park, Ok Kyu; Kim, Hyunbum; Varghese, Shyni

    2015-01-01

    Articular cartilage damage is a persistent and increasing problem with the aging population. Strategies to achieve complete repair or functional restoration remain a challenge. Photopolymerizing-based hydrogels have long received an attention in the cartilage tissue engineering, due to their unique bioactivities, flexible method of synthesis, range of constituents, and desirable physical characteristics. In the present study, we have introduced unique bioactivity within the photopolymerizing-based hydrogels by copolymerizing polyethylene glycol (PEG) macromers with methacrylated extracellular matrix (ECM) molecules (hyaluronic acid and chondroitin sulfate [CS]) and integrin binding peptides (RGD peptide). Results indicate that cellular morphology, as observed by the actin cytoskeleton structures, was strongly dependent on the type of ECM component as well as the presence of integrin binding moieties. Further, CS-based hydrogel with integrin binding RGD moieties increased the lubricin (or known as superficial zone protein [SZP]) gene expression of the encapsulated chondrocytes. Additionally, CS-based hydrogel displayed cell-responsive degradation and resulted in increased DNA, GAG, and collagen accumulation compared with other hydrogels. This study demonstrates that integrin-mediated interactions within CS microenvironment provide an optimal hydrogel scaffold for cartilage tissue engineering application. PMID:25266634

  11. Microfluidics: Science and Engineering at the Edge of the Continuum

    NASA Astrophysics Data System (ADS)

    Breuer, Kenny

    2002-11-01

    The widespread growth of microengineering and the development of a new generation of micron- and nanometer scale diagnostic techniques has focussed much recent attention on the mechanics of fluids at the micron and sub-micron scale. Challenges with both scientific and engineering relevance have been raised by this activity, ranging from the prediction of viscous damping and lubrication effects in MEMS to the design of microengines to the understanding of bacterial propulsion. Identifying and addressing these challenges form the basis of this talk. >From a scientific perspective, a question that refuses to die is that of the applicability of the continuum hypothesis, and the possible existence of new physical phenomena only observable in small systems. To be brief, the reports of the demise of the Navier-Stokes equations are greatly exaggerated and to illustrate this we will review the more recent work on near-continuum fluid mechanics in micron and sub-micron scale devices with an emphasis on our own experiments on the breakdown of the continuum description in both gaseous and liquid flows. From an engineering perspective, the tight coupling between fluids, structures and manufacturing result in flows characterized by unfamiliar parameter regimes and unconventional geometries. We will look at several examples of such microfluidic engineering, drawn from MEMS (inertial instruments, microengines) and biology (bacterial propulsion) that illustrate the the unique design challenges that we encounter in microfluidic devices and the solutions (and lack of solutions) to these problems.

  12. Nanotechnology: Opportunities and Challenges

    NASA Technical Reports Server (NTRS)

    Meyyappan, Meyya

    2003-01-01

    Nanotechnology seeks to exploit novel physical, chemical, biological, mechanical, electrical, and other properties, which arise primarily due to the nanoscale nature of certain materials. A key example is carbon nanotubes (CNTs) which exhibit unique electrical and extraordinary mechanical properties and offer remarkable potential for revolutionary applications in electronics devices, computing, and data storage technology, sensors, composites, nanoelectromechanical systems (NEMS), and as tip in scanning probe microscopy (SPM) for imaging and nanolithography. Thus the CNT synthesis, characterization, and applications touch upon all disciplines of science and engineering. This presentation will provide an overview and progress report on this and other major research candidates in Nanotechnology and address opportunities and challenges ahead.

  13. (Extreme) Core-collapse Supernova Simulations

    NASA Astrophysics Data System (ADS)

    Mösta, Philipp

    2017-01-01

    In this talk I will present recent progress on modeling core-collapse supernovae with massively parallel simulations on the largest supercomputers available. I will discuss the unique challenges in both input physics and computational modeling that come with a problem involving all four fundamental forces and relativistic effects and will highlight recent breakthroughs overcoming these challenges in full 3D simulations. I will pay particular attention to how these simulations can be used to reveal the engines driving some of the most extreme explosions and conclude by discussing what remains to be done in simulation work to maximize what we can learn from current and future time-domain astronomy transient surveys.

  14. Space Shuttle Main Engine - The Relentless Pursuit of Improvement

    NASA Technical Reports Server (NTRS)

    VanHooser, Katherine P.; Bradley, Douglas P.

    2011-01-01

    The Space Shuttle Main Engine (SSME) is the only reusable large liquid rocket engine ever developed. The specific impulse delivered by the staged combustion cycle, substantially higher than previous rocket engines, minimized volume and weight for the integrated vehicle. The dual pre-burner configuration permitted precise mixture ratio and thrust control while the fully redundant controller and avionics provided a very high degree of system reliability and health diagnosis. The main engine controller design was the first rocket engine application to incorporate digital processing. The engine was required to operate at a high chamber pressure to minimize engine volume and weight. Power level throttling was required to minimize structural loads on the vehicle early in flight and acceleration levels on the crew late in ascent. Fatigue capability, strength, ease of assembly and disassembly, inspectability, and materials compatibility were all major considerations in achieving a fully reusable design. During the multi-decade program the design evolved substantially using a series of block upgrades. A number of materials and manufacturing challenges were encountered throughout SSME s history. Significant development was required for the final configuration of the high pressure turbopumps. Fracture control was implemented to assess life limits of critical materials and components. Survival in the hydrogen environment required assessment of hydrogen embrittlement. Instrumentation systems were a challenge due to the harsh thermal and dynamic environments within the engine. Extensive inspection procedures were developed to assess the engine components between flights. The Space Shuttle Main Engine achieved a remarkable flight performance record. All flights were successful with only one mission requiring an ascent abort condition, which still resulted in an acceptable orbit and mission. This was achieved in large part via extensive ground testing to fully characterize performance and to establish acceptable life limits. During the program over a million seconds of accumulated test and flight time was achieved. Post flight inspection and assessment was a key part of assuring proper performance of the flight hardware. By the end of the program the predicted reliability had improved by a factor of four. These unique challenges, evolution of the design, and the resulting reliability will be discussed in this paper.

  15. Gas Turbine Engine with Air/Fuel Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Krautheim, Michael Stephen (Inventor); Chouinard, Donald G. (Inventor); Donovan, Eric Sean (Inventor); Karam, Michael Abraham (Inventor); Vetters, Daniel Kent (Inventor)

    2017-01-01

    One embodiment of the present invention is a unique aircraft propulsion gas turbine engine. Another embodiment is a unique gas turbine engine. Another embodiment is a unique gas turbine engine. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for gas turbine engines with heat exchange systems. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith.

  16. Mechatronics as a technological basis for an innovative learning environment in engineering

    NASA Astrophysics Data System (ADS)

    Garner, Gavin Thomas

    Mechatronic systems that couple mechanical and electrical systems with the help of computer control are forcing a paradigm shift in the design, manufacture, and implementation of mechanical devices. The inherently interdisciplinary nature of these systems generates exciting new opportunities for developing a hands-on, inventive, and creativity-focused educational program while still embracing rigorous scientific fundamentals. The technologies associated with mechatronics are continually evolving (e.g., integrated circuit chips, miniature and new types of sensors, and state-of-the-art actuators). As a result, a mechatronics curriculum must prepare students to adapt along with these rapidly changing technologies---and perhaps even advance these technologies themselves. Such is the inspiring and uncharted new world that is presented for student exploration and experimentation in the University of Virginia's Mechatronics Laboratory. The underlying goal of this research has been to develop a framework for teaching mechatronics that helps students master fundamental concepts and build essential technical and analytical skills. To this end, two courses involving over fifty hours worth of technologically-innovative and educationally-effective laboratory experiments have been developed along with open-ended projects in response to the unique and new challenges associated with teaching mechatronics. These experiments synthesize an unprecedentedly vast array of skills from many different disciplines and enable students to haptically absorb the fundamental concepts involved in designing mechatronic systems. They have been optimized through several iterations to become highly efficient. Perspectives on the development of these courses and on the field of mechatronics in general are included. Furthermore, this dissertation demonstrates the integration of new technologies within a learning environment specifically designed to teach mechatronics to mechanical engineers. For mechanical engineering in particular, mechatronics poses considerable challenges, and necessitates a fundamental evolution in the understanding of the relationship between the various engineering disciplines. Consequently, this dissertation helps to define the role that mechatronics must play in mechanical engineering and presents unique laboratory experiments, creative projects, and modeling and simulation exercises as effective tools for teaching mechatronics to the modern mechanical engineering student.

  17. Probing thyroglobulin in undiluted human serum based on pattern recognition and competitive adsorption of proteins

    NASA Astrophysics Data System (ADS)

    Wang, Ran; Huang, Shuai; Li, Jing; Chae, Junseok

    2014-10-01

    Thyroglobulin (Tg) is a sensitive indicator of persistent or recurrent differentiated thyroid cancer of follicular cell origin. Detection of Tg in human serum is challenging as bio-receptors, such as anti-Tg, used in immunoassay have relatively weak binding affinity. We engineer sensing surfaces using the competitive adsorption of proteins, termed the Vroman Effect. Coupled with Surface Plasmon Resonance, the "cross-responsive" interactions of Tg on the engineered surfaces produce uniquely distinguishable multiple signature patterns, which are discriminated using Linear Discriminant Analysis. Tg-spiked samples, down to 2 ng/ml Tg in undiluted human serum, are sensitively and selectively discriminated from the control (undiluted human serum).

  18. Human Factors Engineering and testing for a wearable, long duration ultrasound system self-applied by an end user.

    PubMed

    Taggart, Rebecca; Langer, Matthew D; Lewis, George K

    2014-01-01

    One of the major challenges in the design of a new class of medical device is ensuring that the device will have a safe and effective user interface for the intended users. Human Factors Engineering addresses these concerns through direct study of how a user interacts with newly designed devices with unique features. In this study, a novel long duration, low intensity therapeutic ultrasound device is tested by 20 end users representative of the intended user population. Over 90% of users were able to operate the device successfully. The therapeutic ultrasound device was found to be reasonably safe and effective for the intended users, uses, and use environments.

  19. 40 CFR 86.085-37 - Production vehicles and engines.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... transmission class. (2) Base level means a unique combination of basic engine, inertia weight, and transmission class. (3) Vehicle configuration means a unique combination of basic engine, engine code, inertia weight...

  20. Overview of Propellant Delivery Systems at the NASA John C. Stennis Space Center

    NASA Technical Reports Server (NTRS)

    Haselmaier, L. Haynes; Field, Robert E.; Ryan, Harry M.; Dickey, Jonathan C.

    2006-01-01

    A wide range of rocket propulsion test work occurs at he NASA John C. Stennis Space Center (SSC) including full-scale engine test activities at test facilities A-1, A-2, B-1 and B-2 as well as combustion device research and development activities at the E-Complex (E-1, E-2. E-3 and E-4) test facilities. One of the greatest challenges associated with operating a test facility is maintaining the health of the primary propellant system and test-critical support systems. The challenge emerges due to the fact that the operating conditions of the various system components are extreme (e.g., low temperatures, high pressures) and due to the fact that many of the components and systems are unique. The purpose of this paper is to briefly describe the experience and modeling techniques that are used to operate the unique test facilities at NASA SSC that continue to support successful propulsion testing.

  1. Addressing the paradox of the team innovation process: A review and practical considerations.

    PubMed

    Thayer, Amanda L; Petruzzelli, Alexandra; McClurg, Caitlin E

    2018-01-01

    Facilitating team innovation is paramount to promoting progress in the science, technology, engineering, and math fields, as well as advancing national health, safety, prosperity, and welfare. However, innovation teams face a unique set of challenges due to the novelty and uncertainty that is core to the definition of innovation, as well as the paradoxical nature of idea generation and idea implementation processes. These and other challenges must be overcome for innovation teams to realize their full potential for producing change. The purpose of this review is, thus, to provide insight into the unique context that these teams function within and provide an integrative, evidence-based, and practically useful, organizing heuristic that focuses on the most important considerations for facilitating team innovation. Finally, we provide practical guidance for psychologists, organizations, practitioners, scientists, educators, policymakers, and others who employ teams to produce novel, innovative solutions to today's problems. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  2. Realizing the Promise of Chemical Glycobiology.

    PubMed

    Wang, Lai-Xi; Davis, Benjamin G

    2013-09-01

    Chemical glycobiology is emerging as one of the most uniquely powerful sub-disciplines of chemical biology. The previous scarcity of chemical strategies and the unparalleled structural diversity have created a uniquely fertile ground that is both rich in challenges and potentially very profound in implications. Glycans (oligosaccharides, polysaccharides, and glycoconjugates) are everywhere in biological systems and yet remain disproportionately neglected - reviews highlighting this 'Cinderella status' abound. Yet, the last two decades have witnessed tremendous progress, notably in chemical and chemoenzymatic synthesis, 'sequencing' and arraying, metabolic engineering and imaging. These vital steps serve to highlight not only the great potential but just how much more remains to be done. The vast chemical and functional space of glycans remains to be truly explored. Top-down full-scale glycomic and glycoproteomic studies coupled with hypothesis-driven, bottom-up innovative chemical strategies will be required to properly realize the potential impact of glycoscience on human health, energy, and economy. In this review, we cherry-pick far-sighted advances and use these to identify possible challenges, opportunities and avenues in chemical glycobiology.

  3. The challenge of logistics facilities development

    NASA Technical Reports Server (NTRS)

    Davis, James R.

    1987-01-01

    The paper discusses the experiences of a group of engineers and logisticians at John F. Kennedy Space center in the design, construction and activation of a consolidated logistics facility for support of Space Transportation System ground operations and maintenance. The planning, methodology and processes are covered, with emphasis placed on unique aspects and lessons learned. The project utilized a progressive design, baseline and build concept for each phase of construction, with the Government exercising funding and configuration oversight.

  4. Diversity: The Business Case?

    NASA Astrophysics Data System (ADS)

    Jones, B.

    2013-12-01

    Understanding perceptions and managing expectations are learnable skills that do not necessarily come with project funding. Finding life balance as one moves through a STEM career path poses unique challenges that require a certain skill set that is not always intuitive. Some of those challenges include: selecting grad or post doc positions; balancing work and family commitments; and dealing with employer/advisor perceptions and expectations. As in nature, the STEM enterprise requires multiple perspectives to flourish (necessity of peer review), and in a changing environment (e.g., budget, generations, technology, etc.), embracing diversity in thought and application may help drive the evolution of STEM in the U.S. Many Agencies and organizations have ';workforce development' programs that focus on preparing the next generation of scientists and engineers at the graduate and undergraduate level that focus on preparing students in the diverse disciplines that are unique to those Agency and organizational missions. While financial support certainly is critical to assist students in Science Technology Engineering and Mathematics (STEM) and other fields, professional development is just as important to equip students with a balanced arsenal of tactics to be successful professionals in the STEM workforce of today. Success in these efforts requires an honest look at the issue of inequality in the STEM ecosystem... meaning, what initiatives have been successful in addressing the imbalance in sources of thought and application, therefore promoting the importance of diversity.

  5. Diversity: The business case for and benefits of

    NASA Astrophysics Data System (ADS)

    Jones, M. B.

    2013-05-01

    Many Federal Agencies have 'workforce development' programs that focus on preparing the next generation of scientists and engineers at the graduate and undergraduate level. Several of the science Agencies (e.g., NASA, NOAA, EPA, etc.), have programs that support students in many of the diverse disciplines that are unique to those Agency missions. While financial support certainly is critical to assist students in the STEM and other fields, professional development is just as important to equip students with a balanced arsenal of tactics to be successful professionals in the STEM workforce of today. Understanding perceptions and managing expectations are learnable skills that do not necessarily come with project funding. Finding life balance as one moves through a STEM career path poses unique challenges that require a certain skill set that is not always intuitive. Some of those challenges include: selecting grad or post doc positions (negotiating to a family's advantage); balancing work and family commitments; and dealing with employer/advisor perceptions and expectations. Since the scientific enterprise requires multiple perspectives to flourish (e.g., peer review), many of the above mentioned challenges require additional skill in negotiating interactions with individuals from a variety of backgrounds… with as many perspectives.

  6. Integrating Global Hydrology Into Graduate Engineering Education and Research

    NASA Astrophysics Data System (ADS)

    Griffis, V. W.

    2007-12-01

    Worldwide, polluted water affects the health of 1.2 billion people and contributes to the death of 15 million children under five every year. In addition poor environmental quality contributes to 25 per cent of all preventable ill health in the world. To address some of these problems, at the 2002 World Summit on Sustainable Development, the world community set the goal of halving, by the year 2015, the proportion of people without access to safe drinking water and basic sanitation. Solving sanitation and water resource management problems in any part of the world presents an interdisciplinary, complex challenge. However, when we attempt to solve these problems in an international context, our technical approaches must be tempered with cultural sensitivity and extraordinary management strategies. To meet this challenge, Michigan Tech has developed a unique global partnership with the U.S. Peace Corps to address our acknowledgement of the importance of placing engineering solutions in a global context. The program has graduated 30 students. Program enrollment is now over 30 and over 20 countries have hosted our students. The objective of this presentation is to demonstrate how this unique partnership can be integrated with graduate engineering education and research and also show how such a program may attract a more diverse student population into engineering. All graduate students enrolled in our Master's International Program in Civil and Environmental Engineering must complete specific coursework requirements before departing for their international experience. In CE5993 (Field Engineering in the Developing World) students learn to apply concepts of sustainable development and appropriate technology in the developing world. In FW5770 (Rural Community Development Planning and Analysis) students learn how one involves a community in the decision making process. A common theme in both courses is the role of woman in successful development projects. Technical specialization allows a student to take coursework in hydrology, water planning and management, and water quality engineering. The 2-3 semester residence on campus is then followed by three months of cultural, language, and technical training with the Peace Corps. After training students complete two years of service in the Peace Corps, typically working as a water/sanitation engineer while also completing a research project related to their Peace Corps experience. Some unique aspects of the Peace Corps experience is that it provides students with cultural awareness, language proficiency, community organizing skills, skills in consensus building and sustainable development, appreciation for technology that is economically and culturally sensitive, and a long-term field experience to develop an indepth overseas research project. Perhaps one of the greatest aspects of the Peace Corps experience is it provides students a basis to consider the social, economic, and environmental limitations of water projects in the developing world. Some examples of research projects that have been integrated into this program are: (a) culturally appropriate watershed planning and management, (b) technical capacity building of water supply systems, and (c) life cycle thinking approach applied to water and sanitation projects.

  7. ACTIVIS: Visual Exploration of Industry-Scale Deep Neural Network Models.

    PubMed

    Kahng, Minsuk; Andrews, Pierre Y; Kalro, Aditya; Polo Chau, Duen Horng

    2017-08-30

    While deep learning models have achieved state-of-the-art accuracies for many prediction tasks, understanding these models remains a challenge. Despite the recent interest in developing visual tools to help users interpret deep learning models, the complexity and wide variety of models deployed in industry, and the large-scale datasets that they used, pose unique design challenges that are inadequately addressed by existing work. Through participatory design sessions with over 15 researchers and engineers at Facebook, we have developed, deployed, and iteratively improved ACTIVIS, an interactive visualization system for interpreting large-scale deep learning models and results. By tightly integrating multiple coordinated views, such as a computation graph overview of the model architecture, and a neuron activation view for pattern discovery and comparison, users can explore complex deep neural network models at both the instance- and subset-level. ACTIVIS has been deployed on Facebook's machine learning platform. We present case studies with Facebook researchers and engineers, and usage scenarios of how ACTIVIS may work with different models.

  8. Extending Synthetic Routes for Oligosaccharides by Enzyme, Substrate and Reaction Engineering

    NASA Astrophysics Data System (ADS)

    Seibel, Jürgen; Jördening, Hans-Joachim; Buchholz, Klaus

    The integration of all relevant tools for bioreaction engineering has been a recent challenge. This approach should notably favor the production of oligo- and polysaccharides, which is highly complex due to the requirements of regio- and stereoselectivity. Oligosaccharides (OS) and polysaccharides (PS) have found many interests in the fields of food, pharmaceuticals, and cosmetics due to different specific properties. Food, sweeteners, and food ingredients represent important sectors where OS are used in major amounts. Increasing attention has been devoted to the sophisticated roles of OS and glycosylated compounds, at cell or membrane surfaces, and their function, e.g., in infection and cancer proliferation. The challenge for synthesis is obvious, and convenient approaches using cheap and readily available substrates and enzymes will be discussed. We report on new routes for the synthesis of oligosaccharides (OS), with emphasis on enzymatic reactions, since they offer unique properties, proceeding highly regio- and stereoselective in water solution, and providing for high yields in general.

  9. 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.

  10. A proven approach for more effective software development and maintenance

    NASA Technical Reports Server (NTRS)

    Pajerski, Rose; Hall, Dana; Sinclair, Craig

    1994-01-01

    Modern space flight mission operations and associated ground data systems are increasingly dependent upon reliable, quality software. Critical functions such as command load preparation, health and status monitoring, communications link scheduling and conflict resolution, and transparent gateway protocol conversion are routinely performed by software. Given budget constraints and the ever increasing capabilities of processor technology, the next generation of control centers and data systems will be even more dependent upon software across all aspects of performance. A key challenge now is to implement improved engineering, management, and assurance processes for the development and maintenance of that software; processes that cost less, yield higher quality products, and that self-correct for continual improvement evolution. The NASA Goddard Space Flight Center has a unique experience base that can be readily tapped to help solve the software challenge. Over the past eighteen years, the Software Engineering Laboratory within the code 500 Flight Dynamics Division has evolved a software development and maintenance methodology that accommodates the unique characteristics of an organization while optimizing and continually improving the organization's software capabilities. This methodology relies upon measurement, analysis, and feedback much analogous to that of control loop systems. It is an approach with a time-tested track record proven through repeated applications across a broad range of operational software development and maintenance projects. This paper describes the software improvement methodology employed by the Software Engineering Laboratory, and how it has been exploited within the Flight Dynamics Division with GSFC Code 500. Examples of specific improvement in the software itself and its processes are presented to illustrate the effectiveness of the methodology. Finally, the initial findings are given when this methodology was applied across the mission operations and ground data systems software domains throughout Code 500.

  11. Protein based therapeutic delivery agents: Contemporary developments and challenges.

    PubMed

    Yin, Liming; Yuvienco, Carlo; Montclare, Jin Kim

    2017-07-01

    As unique biopolymers, proteins can be employed for therapeutic delivery. They bear important features such as bioavailability, biocompatibility, and biodegradability with low toxicity serving as a platform for delivery of various small molecule therapeutics, gene therapies, protein biologics and cells. Depending on size and characteristic of the therapeutic, a variety of natural and engineered proteins or peptides have been developed. This, coupled to recent advances in synthetic and chemical biology, has led to the creation of tailor-made protein materials for delivery. This review highlights strategies employing proteins to facilitate the delivery of therapeutic matter, addressing the challenges for small molecule, gene, protein and cell transport. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    Sanz Rodrigo, Javier; Chávez Arroyo, Roberto Aurelio; Moriarty, Patrick

    The increasing size of wind turbines, with rotors already spanning more than 150 m diameter and hub heights above 100 m, requires proper modeling of the atmospheric boundary layer (ABL) from the surface to the free atmosphere. Furthermore, large wind farm arrays create their own boundary layer structure with unique physics. This poses significant challenges to traditional wind engineering models that rely on surface-layer theories and engineering wind farm models to simulate the flow in and around wind farms. However, adopting an ABL approach offers the opportunity to better integrate wind farm design tools and meteorological models. The challenge ismore » how to build the bridge between atmospheric and wind engineering model communities and how to establish a comprehensive evaluation process that identifies relevant physical phenomena for wind energy applications with modeling and experimental requirements. A framework for model verification, validation, and uncertainty quantification is established to guide this process by a systematic evaluation of the modeling system at increasing levels of complexity. In terms of atmospheric physics, 'building the bridge' means developing models for the so-called 'terra incognita,' a term used to designate the turbulent scales that transition from mesoscale to microscale. This range of scales within atmospheric research deals with the transition from parameterized to resolved turbulence and the improvement of surface boundary-layer parameterizations. The coupling of meteorological and wind engineering flow models and the definition of a formal model evaluation methodology, is a strong area of research for the next generation of wind conditions assessment and wind farm and wind turbine design tools. Some fundamental challenges are identified in order to guide future research in this area.« less

  13. Alpbach Summer School - a unique learning experience

    NASA Astrophysics Data System (ADS)

    Kern, K.; Aulinas, J.; Clifford, D.; Krejci, D.; Topham, R.

    2011-12-01

    The Alpbach Summer School is a ten-day program that provides a unique opportunity for young european science and engineering students, both undergraduate and graduate, to learn how to approach the entire design process of a space mission. The theme of the 2010 Summer School was "New Space Missions to Understand Climate Change", a current, challenging, very broad and complex topic. The program was established more than 35 years ago and is organised in two interrelated parts: a series of lectures held by renowned experts in the field (in the case of this specific year, climate change and space engineering experts) that provides a technical and scientific background for the workshops that follow, the core of the Summer School. For the workshops the students are split into four international, interdisciplinary teams of about 15 students. In 2010 every team had to complete a number of tasks, four in total: (1) identify climate change research gaps and design a space mission that has not yet been flown or proposed, (2) define the science objectives and requirements of the mission, (3) design a spacecraft that meets the mission requirements, which includes spacecraft design and construction, payload definition, orbit calculations, but also the satellite launch, operation and mission costs and (4) write up a short mission proposal and present the results to an expert review panel. Achieving these tasks in only a few days in a multicultural, interdisciplinary team represents a major challenge for all participants and provides an excellent practical learning experience. Over the course of the program, students do not just learn facts about climate change and space engineering, but scientists also learn from engineers and engineers from scientists. The participants have to deepen their knowledge in an often unfamiliar field, develop organisational and team-work skills and work under pressure. Moreover, teams are supported by team and roving tutors and get the opportunity to meet and learn from international experts. This presentation will provide an overview of the Alpbach Summer School program from a student's perspective. The different stages of this unique and enriching experience will be covered. Special attention will be paid to the workshops, which, as mentioned above, are the core of the Alpbach Summer School. During these intense workshops, participants work towards the proposed goals resulting in the design proposal of a space mission. The Alpbach Summer School is organised by FFG and co-sponsored by ESA, ISSI and the national space authorities of ESA member and cooperating states.

  14. Engine systems and methods of operating an engine

    DOEpatents

    Scotto, Mark Vincent

    2015-08-25

    One embodiment of the present invention is a unique method for operating an engine. Another embodiment is a unique engine system. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for engines and engine systems. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith.

  15. Engine systems and methods of operating an engine

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

    Scotto, Mark Vincent

    One embodiment of the present invention is a unique method for operating an engine. Another embodiment is a unique engine system. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for engines and engine systems. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith.

  16. Bioprinting is changing regenerative medicine forever.

    PubMed

    Collins, Scott Forrest

    2014-12-01

    3D printing, or solid freeform fabrication, applied to regenerative medicine brings technologies from several industries together to help solve unique challenges in both basic science and tissue engineering. By more finely organizing cells and supporting structures precisely in 3D space, we will gain critical knowledge of cell-cell communications and cell-environment interactions. As we increase the scale, we will move toward complex tissue and organ structures where several cell phenotypes will functionally and structurally interact, thus recapitulating the form and function of native tissues and organs.

  17. Institute for Sustainable Energy

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

    Agrawal, Ajay

    2016-03-28

    Alternate fuels offer unique challenges and opportunities as energy source for power generation, vehicular transportation, and industrial applications. Institute for Sustainable Energy (ISE) at UA conducts innovative research to utilize the complex mix of domestically-produced alternate fuels to achieve low-emissions, high energy-efficiency, and fuel-flexibility. ISE also provides educational and advancement opportunities to students and researchers in the energy field. Basic research probing the physics and chemistry of alternative fuels has generated practical concepts investigated in a burner and engine test platforms.

  18. Using Acellular Bioactive Extracellular Matrix Scaffolds to Enhance Endogenous Cardiac Repair

    PubMed Central

    Svystonyuk, Daniyil A.; Mewhort, Holly E. M.; Fedak, Paul W. M.

    2018-01-01

    An inability to recover lost cardiac muscle following acute ischemic injury remains the biggest shortcoming of current therapies to prevent heart failure. As compared to standard medical and surgical treatments, tissue engineering strategies offer the promise of improved heart function by inducing regeneration of functional heart muscle. Tissue engineering approaches that use stem cells and genetic manipulation have shown promise in preclinical studies but have also been challenged by numerous critical barriers preventing effective clinical translational. We believe that surgical intervention using acellular bioactive ECM scaffolds may yield similar therapeutic benefits with minimal translational hurdles. In this review, we outline the limitations of cellular-based tissue engineering strategies and the advantages of using acellular biomaterials with bioinductive properties. We highlight key anatomic targets enriched with cellular niches that can be uniquely activated using bioactive scaffold therapy. Finally, we review the evolving cardiovascular tissue engineering landscape and provide critical insights into the potential therapeutic benefits of acellular scaffold therapy. PMID:29696148

  19. Strengthening Environmental Engineering Education in Afghanistan through Cooperating Military Academies

    NASA Astrophysics Data System (ADS)

    Christ, J. A.; Mahbob, M.; Seely, G. E.; Ressler, S. J.

    2007-12-01

    Many developing countries suffer from substandard employment of environmental engineering and science principles, which leads to poor management of natural and cultural resources, increased public health concerns, and limitations on economic investment and growth. Thus, prior to the implementation of well-intentioned programs designed to promote development, methods for sustaining basic needs, which are the focus of most environmental engineering disciplines, must be designed into the social fabric of the developing culture. Education is a promising method for fostering this development across cultures. Recently, the US Air Force Academy (USAFA) partnered with the US Military Academy (USMA) to implement a Civil Engineering Program at the National Military Academy of Afghanistan (NMAA), Kabul, Afghanistan. This work will outline the process followed during course development, deployment, and implementation, paying particular attention to challenges and benefits at each stage in the process. This cooperation may serve as a model for future implementation of science, technology, engineering and mathematics education programs in developing countries. Consistent with US Civil Engineering programs, the NMAA Civil Engineering program introduces students to a broad range of introductory-level civil engineering subjects--environmental, hydraulic, geotechnical, structural, construction, and transportation engineering. Basic environmental engineering and science principles are addressed through the implementation of an introductory environmental engineering course. Course development followed a three-stage process: (1) course development by US faculty at their home institution, (2) imbedding of US Faculty at the NMAA, and (3) implementation of the course within the NMAA Civil Engineering curriculum using adjunct Afghan faculty hired from Kabul University. An existing environmental engineering course taught at USAFA was used as a model for course development. Although this existing course provided the necessary framework for the Afghan course, there were a number of challenges with tailoring the course material to the education level, experience, and needs of the Afghan students and faculty. These challenges were overcome, in part, during the imbedding process of US instructors within the NMAA faculty. On-site transfer of course material and knowledge proved a necessary step in the implementation of the course. The imbedding process enabled US instructors to discuss the course with current NMAA faculty and identify an implementation path that met the needs of the program while appreciating the uniqueness of the Afghan experience. Implementation of the course is on-going with reach-back capability for Afghan faculty to continue the mentoring relationship with their US colleagues. Challenges that arise during course implementation (e.g., wet lab deployments, field trip relevance) will be overcome and used as learning tools for future course offerings. Ultimately, this course will provide future leaders of Afghanistan with the educational tools to make informed environmental management decisions and will serve as a model for similar courses implemented throughout Afghanistan.

  20. Solar Thermal Upper Stage Liquid Hydrogen Pressure Control Testing and Analytical Modeling

    NASA Technical Reports Server (NTRS)

    Olsen, A. D.; Cady, E. C.; Jenkins, D. S.; Chandler, F. O.; Grayson, G. D.; Lopez, A.; Hastings, L. J.; Flachbart, R. H.; Pedersen, K. W.

    2012-01-01

    The demonstration of a unique liquid hydrogen (LH2) storage and feed system concept for solar thermal upper stage was cooperatively accomplished by a Boeing/NASA Marshall Space Flight Center team. The strategy was to balance thermodynamic venting with the engine thrusting timeline during a representative 30-day mission, thereby, assuring no vent losses. Using a 2 cubic m (71 cubic ft) LH2 tank, proof-of-concept testing consisted of an engineering checkout followed by a 30-day mission simulation. The data were used to anchor a combination of standard analyses and computational fluid dynamics (CFD) modeling. Dependence on orbital testing has been incrementally reduced as CFD codes, combined with standard modeling, continue to be challenged with test data such as this.

  1. The Dawning of the Ethics of Environmental Robots.

    PubMed

    van Wynsberghe, Aimee; Donhauser, Justin

    2017-10-23

    Environmental scientists and engineers have been exploring research and monitoring applications of robotics, as well as exploring ways of integrating robotics into ecosystems to aid in responses to accelerating environmental, climatic, and biodiversity changes. These emerging applications of robots and other autonomous technologies present novel ethical and practical challenges. Yet, the critical applications of robots for environmental research, engineering, protection and remediation have received next to no attention in the ethics of robotics literature to date. This paper seeks to fill that void, and promote the study of environmental robotics. It provides key resources for further critical examination of the issues environmental robots present by explaining and differentiating the sorts of environmental robotics that exist to date and identifying unique conceptual, ethical, and practical issues they present.

  2. Novel Multidisciplinary Models Assess the Capabilities of Smart Structures to Manage Vibration, Sound, and Thermal Distortion in Aeropropulsion Components

    NASA Technical Reports Server (NTRS)

    Saravanos, Dimitris A.

    1997-01-01

    The development of aeropropulsion components that incorporate "smart" composite laminates with embedded piezoelectric actuators and sensors is expected to ameliorate critical problems in advanced aircraft engines related to vibration, noise emission, and thermal stability. To facilitate the analytical needs of this effort, the NASA Lewis Research Center has developed mechanics and multidisciplinary computational models to analyze the complicated electromechanical behavior of realistic smart-structure configurations operating in combined mechanical, thermal, and acoustic environments. The models have been developed to accommodate the particular geometries, environments, and technical challenges encountered in advanced aircraft engines, yet their unique analytical features are expected to facilitate application of this new technology in a variety of commercial applications.

  3. DNA-mediated engineering of multicomponent enzyme crystals

    PubMed Central

    Brodin, Jeffrey D.; Auyeung, Evelyn; Mirkin, Chad A.

    2015-01-01

    The ability to predictably control the coassembly of multiple nanoscale building blocks, especially those with disparate chemical and physical properties such as biomolecules and inorganic nanoparticles, has far-reaching implications in catalysis, sensing, and photonics, but a generalizable strategy for engineering specific contacts between these particles is an outstanding challenge. This is especially true in the case of proteins, where the types of possible interparticle interactions are numerous, diverse, and complex. Herein, we explore the concept of trading protein–protein interactions for DNA–DNA interactions to direct the assembly of two nucleic-acid–functionalized proteins with distinct surface chemistries into six unique lattices composed of catalytically active proteins, or of a combination of proteins and DNA-modified gold nanoparticles. The programmable nature of DNA–DNA interactions used in this strategy allows us to control the lattice symmetries and unit cell constants, as well as the compositions and habit, of the resulting crystals. This study provides a potentially generalizable strategy for constructing a unique class of materials that take advantage of the diverse morphologies, surface chemistries, and functionalities of proteins for assembling functional crystalline materials. PMID:25831510

  4. Unique Chernobyl Cranes for Deconstruction Activities in the New Safe Confinement - 13542

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

    Parameswaran, N.A. Vijay; Chornyy, Igor; Owen, Rob

    2013-07-01

    The devastation left behind from the Chernobyl nuclear power plant (ChNPP) Unit 4 accident which occurred on April 26, 1986 presented unparalleled technical challenges to the world engineering and scientific community. One of the largest tasks that are in progress is the design and construction of the New Safe Confinement (NSC). The NSC is an engineered enclosure for the entire object shelter (OS) that includes a suite of process equipment. The process equipment will be used for the dismantling of the destroyed Chernobyl Nuclear Power Plant (ChNPP) Unit. One of the major mechanical handling systems to be installed in themore » NSC is the Main Cranes System (MCS). The planned decontamination and decommissioning or dismantling (D and D) activities will require the handling of heavily shielded waste disposal casks containing nuclear fuel as well as lifting and transporting extremely large structural elements. These activities, to be performed within the NSC, will require large and sophisticated cranes. The article will focus on the unique design features of the MCS for the D and D activities. (authors)« less

  5. DNA-mediated engineering of multicomponent enzyme crystals

    DOE PAGES

    Brodin, Jeffrey D.; Auyeung, Evelyn; Mirkin, Chad A.

    2015-03-23

    The ability to predictably control the coassembly of multiple nanoscale building blocks, especially those with disparate chemical and physical properties such as biomolecules and inorganic nanoparticles, has far-reaching implications in catalysis, sensing, and photonics, but a generalizable strategy for engineering specific contacts between these particles is an outstanding challenge. This is especially true in the case of proteins, where the types of possible interparticle interactions are numerous, diverse, and complex. In this paper, we explore the concept of trading protein–protein interactions for DNA–DNA interactions to direct the assembly of two nucleic-acid–functionalized proteins with distinct surface chemistries into six unique latticesmore » composed of catalytically active proteins, or of a combination of proteins and DNA-modified gold nanoparticles. The programmable nature of DNA–DNA interactions used in this strategy allows us to control the lattice symmetries and unit cell constants, as well as the compositions and habit, of the resulting crystals. Finally, this study provides a potentially generalizable strategy for constructing a unique class of materials that take advantage of the diverse morphologies, surface chemistries, and functionalities of proteins for assembling functional crystalline materials.« less

  6. Image-based metrology of porous tissue engineering scaffolds

    NASA Astrophysics Data System (ADS)

    Rajagopalan, Srinivasan; Robb, Richard A.

    2006-03-01

    Tissue engineering is an interdisciplinary effort aimed at the repair and regeneration of biological tissues through the application and control of cells, porous scaffolds and growth factors. The regeneration of specific tissues guided by tissue analogous substrates is dependent on diverse scaffold architectural indices that can be derived quantitatively from the microCT and microMR images of the scaffolds. However, the randomness of pore-solid distributions in conventional stochastic scaffolds presents unique computational challenges. As a result, image-based characterization of scaffolds has been predominantly qualitative. In this paper, we discuss quantitative image-based techniques that can be used to compute the metrological indices of porous tissue engineering scaffolds. While bulk averaged quantities such as porosity and surface are derived directly from the optimal pore-solid delineations, the spatially distributed geometric indices are derived from the medial axis representations of the pore network. The computational framework proposed (to the best of our knowledge for the first time in tissue engineering) in this paper might have profound implications towards unraveling the symbiotic structure-function relationship of porous tissue engineering scaffolds.

  7. Advanced degrees in astronautical engineering for the space industry

    NASA Astrophysics Data System (ADS)

    Gruntman, Mike

    2014-10-01

    Ten years ago in the summer of 2004, the University of Southern California established a new unique academic unit focused on space engineering. Initially known as the Astronautics and Space Technology Division, the unit operated from day one as an independent academic department, successfully introduced the full set of degrees in Astronautical Engineering, and was formally renamed the Department of Astronautical Engineering in 2010. The largest component of Department's educational programs has been and continues to be its flagship Master of Science program, specifically focused on meeting engineering workforce development needs of the space industry and government space research and development centers. The program successfully grew from a specialization in astronautics developed in mid-1990s and expanded into a large nationally-visible program. In addition to on-campus full-time students, it reaches many working students on-line through distance education. This article reviews the origins of the Master's degree program and its current status and accomplishments; outlines the program structure, academic focus, student composition, and enrollment dynamics; and discusses lessons learned and future challenges.

  8. Engineering graphene and TMDs based van der Waals heterostructures for photovoltaic and photoelectrochemical solar energy conversion.

    PubMed

    Li, Changli; Cao, Qi; Wang, Faze; Xiao, Yequan; Li, Yanbo; Delaunay, Jean-Jacques; Zhu, Hongwei

    2018-05-08

    Graphene and two-dimensional (2D) transition metal dichalcogenides (TMDs) have attracted significant interest due to their unique properties that cannot be obtained in their bulk counterparts. These atomically thin 2D materials have demonstrated strong light-matter interactions, tunable optical bandgap structures and unique structural and electrical properties, rendering possible the high conversion efficiency of solar energy with a minimal amount of active absorber material. The isolated 2D monolayer can be stacked into arbitrary van der Waals (vdWs) heterostructures without the need to consider lattice matching. Several combinations of 2D/3D and 2D/2D materials have been assembled to create vdWs heterojunctions for photovoltaic (PV) and photoelectrochemical (PEC) energy conversion. However, the complex, less-constrained, and more environmentally vulnerable interface in a vdWs heterojunction is different from that of a conventional, epitaxially grown heterojunction, engendering new challenges for surface and interface engineering. In this review, the physics of band alignment, the chemistry of surface modification and the behavior of photoexcited charge transfer at the interface during PV and PEC processes will be discussed. We will present a survey of the recent progress and challenges of 2D/3D and 2D/2D vdWs heterojunctions, with emphasis on their applicability to PV and PEC devices. Finally, we will discuss emerging issues yet to be explored for 2D materials to achieve high solar energy conversion efficiency and possible strategies to improve their performance.

  9. Science and the major racket sports: a review.

    PubMed

    Lees, Adrian

    2003-09-01

    The major racket sports include badminton, squash, table tennis and tennis. The growth of sports science and the commercialization of racket sports in recent years have focused attention on improved performance and this has led to a more detailed study and understanding of all aspects of racket sports. The aim here, therefore, is to review recent developments of the application of science to racket sports. The scientific disciplines of sports physiology and nutrition, notational analysis, sports biomechanics, sports medicine, sports engineering, sports psychology and motor skills are briefly considered in turn. It is evident from these reviews that a great deal of scientific endeavour has been applied to racket sports, but this is variable across both the racket sports and the scientific disciplines. A scientific approach has helped to: implement training programmes to improve players' fitness; guide players in nutritional and psychological preparation for play; inform players of the strategy and tactics used by themselves and their opponents; provide insight into the technical performance of skills; understand the effect of equipment on play; and accelerate the recovery from racket-arm injuries. Racket sports have also posed a unique challenge to scientists and have provided vehicles for developing scientific methodology. Racket sports provide a good model for investigating the interplay between aerobic and anaerobic metabolism and the effect of nutrition, heat and fatigue on performance. They have driven the development of mathematical solutions for multi-segment interactions within the racket arm during the performance of shots, which have contributed to our understanding of the mechanisms of both performance and injury. They have provided a unique challenge to sports engineers in relation to equipment performance and interaction with the player. Racket sports have encouraged developments in notational analysis both in terms of analytical procedures and the conceptualization of strategy and tactics. Racket sports have provided a vehicle for investigating fast interceptive actions, hand-eye coordination and perception-action coupling in the field of motor control. In conclusion, science has contributed considerably to our knowledge and understanding of racket sports, and racket sports have contributed to science by providing unique challenges to researchers.

  10. Grooker, KartOO, Addict-o-Matic and More: Really Different Search Engines

    ERIC Educational Resources Information Center

    Descy, Don E.

    2009-01-01

    There are hundreds of unique search engines in the United States and thousands of unique search engines around the world. If people get into search engines designed just to search particular web sites, the number is in the hundreds of thousands. This article looks at: (1) clustering search engines, such as KartOO (www.kartoo.com) and Grokker…

  11. Industry careers for the biomedical engineer.

    PubMed

    Munzner, Robert F

    2004-01-01

    This year's conference theme is "linkages for innovation in biomedicine." Biomedical engineers, especially those transitioning their career from academic study into medical device industry, will play a critical role in converting the fruits of scientific research into the reality of modern medical devices. This special session is organized to help biomedical engineers to achieve their career goals more effectively. Participants will have opportunities to hear from and interact with leading industrial experts on many issues. These may include but not limited to 1) career paths for biomedical engineers (industrial, academic, or federal; technical vs. managerial track; small start-up or large established companies); 2) unique design challenges and regulatory requirements in medical device development; 3) aspects of a successful biomedical engineering job candidate (such as resume, interview, follow-up). Suggestions for other topics are welcome and should be directed to xkong@ieee.org The distinguished panelists include: Xuan Kong, Ph.D., VP of Research, NEUROMetrix Inc, Waltham, MA Robert F. Munzner, Ph.D., Medical Device Consultant, Doctor Device, Herndon, VA Glen McLaughlin, Ph.D., VP of Engineering and CTO, Zonare Medical System Inc., Mountain View, CA Grace Bartoo, Ph.D., RAC, General Manager, Decus Biomedical LLC San Carlos, CA.

  12. Day one sustainability

    NASA Astrophysics Data System (ADS)

    Orr, John; Ibell, Timothy; Evernden, Mark; Darby, Antony

    2015-05-01

    Emissions reductions targets for the UK set out in the Climate Change Act for the period to 2050 will only be achieved with significant changes to the built environment, which is currently estimated to account for 50% of the UK's carbon emissions. The socio-technological nature of Civil Engineering means that this field is uniquely placed to lead the UK through such adaptations. This paper discusses the importance of interdisciplinary teaching to produce multi-faceted team approaches to sustainable design solutions. Methods for measuring success in education are often not fit for purpose, producing good students but poor engineers. Real-world failures to apply sustainable design present a serious, difficult to detect, and ultimately economically negative situation. Techniques to replace summative examinations are presented and discussed, with the aim of enhancing core technical skills alongside those required for sustainable design. Finally, the role of our future engineers in policy-making is discussed. In addition to carbon, the provision of water and food will heavily influence the work of civil engineers in the coming decades. Leadership from civil engineers with the technical knowledge and social awareness to tackle these issues will be required. This provides both opportunities and challenges for engineering education in the UK.

  13. Test Results from a High Power Linear Alternator Test Rig

    NASA Technical Reports Server (NTRS)

    Birchenough, Arthur G.; Hervol, David S.; Gardner, Brent G.

    2010-01-01

    Stirling cycle power conversion is an enabling technology that provides high thermodynamic efficiency but also presents unique challenges with regard to electrical power generation, management, and distribution. The High Power Linear Alternator Test Rig (HPLATR) located at the NASA Glenn Research Center (GRC) in Cleveland, OH is a demonstration test bed that simulates electrical power generation from a Stirling engine driven alternator. It implements the high power electronics necessary to provide a well regulated DC user load bus. These power electronics use a novel design solution that includes active rectification and power factor control, active ripple suppression, along with a unique building block approach that permits the use of high voltage or high current alternator designs. This presentation describes the HPLATR, the test program, and the operational results.

  14. Test Results From a High Power Linear Alternator Test Rig

    NASA Technical Reports Server (NTRS)

    Birchenough, Arthur G.; Hervol, David S.; Gardner, Brent G.

    2010-01-01

    Stirling cycle power conversion is an enabling technology that provides high thermodynamic efficiency but also presents unique challenges with regard to electrical power generation, management, and distribution. The High Power Linear Alternator Test Rig (HPLATR) located at the NASA Glenn Research Center (GRC) in Cleveland, Ohio is a demonstration test bed that simulates electrical power generation from a Stirling engine driven alternator. It implements the high power electronics necessary to provide a well regulated DC user load bus. These power electronics use a novel design solution that includes active rectification and power factor control, active ripple suppression, along with a unique building block approach that permits the use of high voltage or high current alternator designs. This report describes the HPLATR, the test program, and the operational results.

  15. Constructibility Challenges for Perimeter Control Blasting and Slope Development in Shale and Other "Weak" Rocks

    NASA Astrophysics Data System (ADS)

    Scarpato, D. J.

    2016-02-01

    Slope construction in shale can present some interesting challenges for geotechnical design engineers and contractors alike. There are challenges that can be expected and designed for; however, all too frequently, such challenges manifest themselves as "surprises" in the field. Common constructibility challenges can include drill hole deviation during drilling for controlled blasting; and, excavation slope instability arising from inconsistent perimeter control drilling. Drill hole deviation results from the cumulative effects from both drilling mechanics and rock mass conditions. Once a hole has initiated the deviation trajectory, it is difficult to rectify drill steel position. Although such challenges are not necessarily unique to shale, they are often exacerbated by weak, weathered and transversely isotropic nature of bedrock conditions. All too often, the working assumption is that shale is "soft" and easily excavatable; however, this blanket assumption can prove to be costly. This paper is intended to provide design professionals and contractors with the practical considerations needed to avoid the "surprises" associated with drill hole deviation, and minimize the potential for costly claims.

  16. Preliminary Outcomes from a Week-Long Environmental Engineering Summer Camp for High School Female Students

    NASA Astrophysics Data System (ADS)

    Balasubramanian, S.; Koloutsou-Vakakis, S.

    2014-12-01

    There is a need for environment engineers and sustainability managers to address global environmental, energy and health challenges. Environmental literacy programs at K-12 level provide a unique opportunity in motivating young minds in joining STEM and also provide additional value in learning about "saving planet earth". The Women in Engineering at the University of Illinois organize an annual week long camp, for female high school students with tracks corresponding to different fields of Engineering. The Environmental Engineering and Sustainability (EES) track is organized by faculty and graduate students of the Civil and Environmental Engineering department and introduces students to concepts in sustainability and systems thinking in connection with air and water quality, climate change and renewable energy. This study is a preliminary assessment of the relevance of the EES outreach track conducted in July 2014 in student learning. Specific goals include assessing (a) demographics of participants and their motivation to join this camp, (b) educational and enjoyability quotients of the modules and (c) learning and motivational outcomes using the Likert scale. A pre-camp survey indicated keen interest in learning about environmental engineering (4.56/5.0) and expected this camp to be a venue to learn about related career choices (4.9/5.0). Five days of instruction were divided thematically and included a mix of lectures, activity based learning, demonstrations and field visits. Overall modules were rated as educational (4.4/5.0) and enjoyable (4.5/5.0). Modules with hands-on learning were best received (4.67/5.0) and rated unique (4.7/5.0). Post camp, participants acknowledged the important contribution of environmental engineers to society (4.8/5.0) and could relate the different modules to the role engineer's play (4.06/5.0) for sustainability. On an average, the participants evinced interest in engineering as a career choice (4.0/5.0) but there was a broader range of responses regarding environmental engineering as their career choice (3.13/5.0).

  17. Carbon nanomaterials for advanced energy conversion and storage.

    PubMed

    Dai, Liming; Chang, Dong Wook; Baek, Jong-Beom; Lu, Wen

    2012-04-23

    It is estimated that the world will need to double its energy supply by 2050. Nanotechnology has opened up new frontiers in materials science and engineering to meet this challenge by creating new materials, particularly carbon nanomaterials, for efficient energy conversion and storage. Comparing to conventional energy materials, carbon nanomaterials possess unique size-/surface-dependent (e.g., morphological, electrical, optical, and mechanical) properties useful for enhancing the energy-conversion and storage performances. During the past 25 years or so, therefore, considerable efforts have been made to utilize the unique properties of carbon nanomaterials, including fullerenes, carbon nanotubes, and graphene, as energy materials, and tremendous progress has been achieved in developing high-performance energy conversion (e.g., solar cells and fuel cells) and storage (e.g., supercapacitors and batteries) devices. This article reviews progress in the research and development of carbon nanomaterials during the past twenty years or so for advanced energy conversion and storage, along with some discussions on challenges and perspectives in this exciting field. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Bi-Axial Solar Array Drive Mechanism: Design, Build and Environmental Testing

    NASA Technical Reports Server (NTRS)

    Scheidegger, Noemy; Ferris, Mark; Phillips, Nigel

    2014-01-01

    The development of the Bi-Axial Solar Array Drive Mechanism (BSADM) presented in this paper is a demonstration of SSTL's unique space manufacturing approach that enables performing rapid development cycles for cost-effective products that meet ever-challenging mission requirements: The BSADM is designed to orient a solar array wing towards the sun, using its first rotation axis to track the sun, and its second rotation axis to compensate for the satellite orbit and attitude changes needed for a successful payload operation. The tight development schedule, with manufacture of 7 Flight Models within 1.5 year after kick-off, is offset by the risk-reduction of using qualified key component-families from other proven SSTL mechanisms. This allowed focusing the BSADM design activities on the mechanism features that are unique to the BSADM, and having an Engineering Qualification Model (EQM) built 8 months after kick-off. The EQM is currently undergoing a full environmental qualification test campaign. This paper presents the BSADM design approach that enabled meeting such a challenging schedule, its design particularities, and the ongoing verification activities.

  19. Life Support Systems for Lunar Landers

    NASA Technical Reports Server (NTRS)

    Anderson, Molly

    2008-01-01

    Engineers designing life support systems for NASA s next Lunar Landers face unique challenges. As with any vehicle that enables human spaceflight, the needs of the crew drive most of the lander requirements. The lander is also a key element of the architecture NASA will implement in the Constellation program. Many requirements, constraints, or optimization goals will be driven by interfaces with other projects, like the Crew Exploration Vehicle, the Lunar Surface Systems, and the Extravehicular Activity project. Other challenges in the life support system will be driven by the unique location of the vehicle in the environments encountered throughout the mission. This paper examines several topics that may be major design drivers for the lunar lander life support system. There are several functional requirements for the lander that may be different from previous vehicles or programs and recent experience. Some of the requirements or design drivers will change depending on the overall Lander configuration. While the configuration for a lander design is not fixed, designers can examine how these issues would impact their design and be prepared for the quick design iterations required to optimize a spacecraft.

  20. NASA Space Flight Vehicle Fault Isolation Challenges

    NASA Technical Reports Server (NTRS)

    Bramon, Christopher; Inman, Sharon K.; Neeley, James R.; Jones, James V.; Tuttle, Loraine

    2016-01-01

    The Space Launch System (SLS) is the new NASA heavy lift launch vehicle and is scheduled for its first mission in 2017. The goal of the first mission, which will be uncrewed, is to demonstrate the integrated system performance of the SLS rocket and spacecraft before a crewed flight in 2021. SLS has many of the same logistics challenges as any other large scale program. Common logistics concerns for SLS include integration of discrete programs geographically separated, multiple prime contractors with distinct and different goals, schedule pressures and funding constraints. However, SLS also faces unique challenges. The new program is a confluence of new hardware and heritage, with heritage hardware constituting seventy-five percent of the program. This unique approach to design makes logistics concerns such as testability of the integrated flight vehicle especially problematic. The cost of fully automated diagnostics can be completely justified for a large fleet, but not so for a single flight vehicle. Fault detection is mandatory to assure the vehicle is capable of a safe launch, but fault isolation is another issue. SLS has considered various methods for fault isolation which can provide a reasonable balance between adequacy, timeliness and cost. This paper will address the analyses and decisions the NASA Logistics engineers are making to mitigate risk while providing a reasonable testability solution for fault isolation.

  1. Proposed Facility Modifications to Support Propulsion Systems Testing Under Simulated Space Conditions at Plum Brook Station's Spacecraft Propulsion Research Facility (B-2)

    NASA Technical Reports Server (NTRS)

    Edwards, Daryl A.

    2008-01-01

    Preparing NASA's Plum Brook Station's Spacecraft Propulsion Research Facility (B-2) to support NASA's new generation of launch vehicles has raised many challenges for B-2's support staff. The facility provides a unique capability to test chemical propulsion systems/vehicles while simulating space thermal and vacuum environments. Designed and constructed in the early 1960s to support upper stage cryogenic engine/vehicle system development, the Plum Brook Station B-2 facility will require modifications to support the larger, more powerful, and more advanced engine systems for the next generation of vehicles leaving earth's orbit. Engine design improvements over the years have included large area expansion ratio nozzles, greater combustion chamber pressures, and advanced materials. Consequently, it has become necessary to determine what facility changes are required and how the facility can be adapted to support varying customers and their specific test needs. Exhaust system performance, including understanding the present facility capabilities, is the primary focus of this work. A variety of approaches and analytical tools are being employed to gain this understanding. This presentation discusses some of the challenges in applying these tools to this project and expected facility configuration to support the varying customer needs.

  2. Proposed Facility Modifications to Support Propulsion Systems Testing Under Simulated Space Conditions at Plum Brook Station's Spacecraft Propulsion Research Facility (B-2)

    NASA Technical Reports Server (NTRS)

    Edwards, Daryl A.

    2007-01-01

    Preparing NASA's Plum Brook Station's Spacecraft Propulsion Research Facility (B-2) to support NASA's new generation of launch vehicles has raised many challenges for B-2 s support staff. The facility provides a unique capability to test chemical propulsion systems/vehicles while simulating space thermal and vacuum environments. Designed and constructed 4 decades ago to support upper stage cryogenic engine/vehicle system development, the Plum Brook Station B-2 facility will require modifications to support the larger, more powerful, and more advanced engine systems for the next generation of vehicles leaving earth's orbit. Engine design improvements over the years have included large area expansion ratio nozzles, greater combustion chamber pressures, and advanced materials. Consequently, it has become necessary to determine what facility changes are required and how the facility can be adapted to support varying customers and their specific test needs. Instrumental in this task is understanding the present facility capabilities and identifying what reasonable changes can be implemented. A variety of approaches and analytical tools are being employed to gain this understanding. This paper discusses some of the challenges in applying these tools to this project and expected facility configuration to support the varying customer needs.

  3. An Approach to Integrating Health Disparities within Undergraduate Biomedical Engineering Education.

    PubMed

    Vazquez, Maribel; Marte, Otto; Barba, Joseph; Hubbard, Karen

    2017-11-01

    Health disparities are preventable differences in the incidence, prevalence and burden of disease among communities targeted by gender, geographic location, ethnicity and/or socio-economic status. While biomedical research has identified partial origin(s) of divergent burden and impact of disease, the innovation needed to eradicate health disparities in the United States requires unique engagement from biomedical engineers. Increasing awareness of the prevalence and consequences of health disparities is particularly attractive to today's undergraduates, who have undauntedly challenged paradigms believed to foster inequality. Here, the Department of Biomedical Engineering at The City College of New York (CCNY) has leveraged its historical mission of access-and-excellence to integrate the study of health disparities into undergraduate BME curricula. This article describes our novel approach in a multiyear study that: (i) Integrated health disparities modules at all levels of the required undergraduate BME curriculum; (ii) Developed opportunities to include impacts of health disparities into undergraduate BME research projects and mentored High School summer STEM training; and (iii) Established health disparities-based challenges as BME capstone design and/or independent entrepreneurship projects. Results illustrate the rising awareness of health disparities among the youngest BMEs-to-be, as well as abundant undergraduate desire to integrate health disparities within BME education and training.

  4. Engineering of the LISA Pathfinder mission—making the experiment a practical reality

    NASA Astrophysics Data System (ADS)

    Warren, Carl; Dunbar, Neil; Backler, Mike

    2009-05-01

    LISA Pathfinder represents a unique challenge in the development of scientific spacecraft—not only is the LISA Test Package (LTP) payload a complex integrated development, placing stringent requirements on its developers and the spacecraft, but the payload also acts as the core sensor and actuator for the spacecraft, making the tasks of control design, software development and system verification unusually difficult. The micro-propulsion system which provides the remaining actuation also presents substantial development and verification challenges. As the mission approaches the system critical design review, flight hardware is completing verification and the process of verification using software and hardware simulators and test benches is underway. Preparation for operations has started, but critical milestones for LTP and field effect electric propulsion (FEEP) lie ahead. This paper summarizes the status of the present development and outlines the key challenges that must be overcome on the way to launch.

  5. Effects of unique biomedical education programs for engineers: REDEEM and ESTEEM projects.

    PubMed

    Matsuki, Noriaki; Takeda, Motohiro; Yamano, Masahiro; Imai, Yohsuke; Ishikawa, Takuji; Yamaguchi, Takami

    2009-06-01

    Current engineering applications in the medical arena are extremely progressive. However, it is rather difficult for medical doctors and engineers to discuss issues because they do not always understand one another's jargon or ways of thinking. Ideally, medical engineers should become acquainted with medicine, and engineers should be able to understand how medical doctors think. Tohoku University in Japan has managed a number of unique reeducation programs for working engineers. Recurrent Education for the Development of Engineering Enhanced Medicine has been offered as a basic learning course since 2004, and Education through Synergetic Training for Engineering Enhanced Medicine has been offered as an advanced learning course since 2006. These programs, which were developed especially for engineers, consist of interactive, modular, and disease-based lectures (case studies) and substantial laboratory work. As a result of taking these courses, all students obtained better objective outcomes, on tests, and subjective outcomes, through student satisfaction. In this article, we report on our unique biomedical education programs for engineers and their effects on working engineers.

  6. 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

  7. OpenWorm: an open-science approach to modeling Caenorhabditis elegans.

    PubMed

    Szigeti, Balázs; Gleeson, Padraig; Vella, Michael; Khayrulin, Sergey; Palyanov, Andrey; Hokanson, Jim; Currie, Michael; Cantarelli, Matteo; Idili, Giovanni; Larson, Stephen

    2014-01-01

    OpenWorm is an international collaboration with the aim of understanding how the behavior of Caenorhabditis elegans (C. elegans) emerges from its underlying physiological processes. The project has developed a modular simulation engine to create computational models of the worm. The modularity of the engine makes it possible to easily modify the model, incorporate new experimental data and test hypotheses. The modeling framework incorporates both biophysical neuronal simulations and a novel fluid-dynamics-based soft-tissue simulation for physical environment-body interactions. The project's open-science approach is aimed at overcoming the difficulties of integrative modeling within a traditional academic environment. In this article the rationale is presented for creating the OpenWorm collaboration, the tools and resources developed thus far are outlined and the unique challenges associated with the project are discussed.

  8. Multiscale Poly-(ϵ-caprolactone) Scaffold Mimicking Nonlinearity in Tendon Tissue Mechanics

    PubMed Central

    Banik, Brittany L.; Lewis, Gregory S.; Brown, Justin L.

    2016-01-01

    Regenerative medicine plays a critical role in the future of medicine. However, challenges remain to balance stem cells, biomaterial scaffolds, and biochemical factors to create successful and effective scaffold designs. This project analyzes scaffold architecture with respect to mechanical capability and preliminary mesenchymal stem cell response for tendon regeneration. An electrospun fiber scaffold with tailorable properties based on a “Chinese-fingertrap” design is presented. The unique criss-crossed fiber structures demonstrate non-linear mechanical response similar to that observed in native tendon. Mechanical testing revealed that optimizing the fiber orientation resulted in the characteristic “S”-shaped curve, demonstrating a toe region and linear elastic region. This project has promising research potential across various disciplines: vascular engineering, nerve regeneration, and ligament and tendon tissue engineering. PMID:27141530

  9. Toward high throughput optical metamaterial assemblies.

    PubMed

    Fontana, Jake; Ratna, Banahalli R

    2015-11-01

    Optical metamaterials have unique engineered optical properties. These properties arise from the careful organization of plasmonic elements. Transitioning these properties from laboratory experiments to functional materials may lead to disruptive technologies for controlling light. A significant issue impeding the realization of optical metamaterial devices is the need for robust and efficient assembly strategies to govern the order of the nanometer-sized elements while enabling macroscopic throughput. This mini-review critically highlights recent approaches and challenges in creating these artificial materials. As the ability to assemble optical metamaterials improves, new unforeseen opportunities may arise for revolutionary optical devices.

  10. Combining phage display with de novo protein sequencing for reverse engineering of monoclonal antibodies.

    PubMed

    Rickert, Keith W; Grinberg, Luba; Woods, Robert M; Wilson, Susan; Bowen, Michael A; Baca, Manuel

    2016-01-01

    The enormous diversity created by gene recombination and somatic hypermutation makes de novo protein sequencing of monoclonal antibodies a uniquely challenging problem. Modern mass spectrometry-based sequencing will rarely, if ever, provide a single unambiguous sequence for the variable domains. A more likely outcome is computation of an ensemble of highly similar sequences that can satisfy the experimental data. This outcome can result in the need for empirical testing of many candidate sequences, sometimes iteratively, to identity one which can replicate the activity of the parental antibody. Here we describe an improved approach to antibody protein sequencing by using phage display technology to generate a combinatorial library of sequences that satisfy the mass spectrometry data, and selecting for functional candidates that bind antigen. This approach was used to reverse engineer 2 commercially-obtained monoclonal antibodies against murine CD137. Proteomic data enabled us to assign the majority of the variable domain sequences, with the exception of 3-5% of the sequence located within or adjacent to complementarity-determining regions. To efficiently resolve the sequence in these regions, small phage-displayed libraries were generated and subjected to antigen binding selection. Following enrichment of antigen-binding clones, 2 clones were selected for each antibody and recombinantly expressed as antigen-binding fragments (Fabs). In both cases, the reverse-engineered Fabs exhibited identical antigen binding affinity, within error, as Fabs produced from the commercial IgGs. This combination of proteomic and protein engineering techniques provides a useful approach to simplifying the technically challenging process of reverse engineering monoclonal antibodies from protein material.

  11. Combining phage display with de novo protein sequencing for reverse engineering of monoclonal antibodies

    PubMed Central

    Rickert, Keith W.; Grinberg, Luba; Woods, Robert M.; Wilson, Susan; Bowen, Michael A.; Baca, Manuel

    2016-01-01

    ABSTRACT The enormous diversity created by gene recombination and somatic hypermutation makes de novo protein sequencing of monoclonal antibodies a uniquely challenging problem. Modern mass spectrometry-based sequencing will rarely, if ever, provide a single unambiguous sequence for the variable domains. A more likely outcome is computation of an ensemble of highly similar sequences that can satisfy the experimental data. This outcome can result in the need for empirical testing of many candidate sequences, sometimes iteratively, to identity one which can replicate the activity of the parental antibody. Here we describe an improved approach to antibody protein sequencing by using phage display technology to generate a combinatorial library of sequences that satisfy the mass spectrometry data, and selecting for functional candidates that bind antigen. This approach was used to reverse engineer 2 commercially-obtained monoclonal antibodies against murine CD137. Proteomic data enabled us to assign the majority of the variable domain sequences, with the exception of 3–5% of the sequence located within or adjacent to complementarity-determining regions. To efficiently resolve the sequence in these regions, small phage-displayed libraries were generated and subjected to antigen binding selection. Following enrichment of antigen-binding clones, 2 clones were selected for each antibody and recombinantly expressed as antigen-binding fragments (Fabs). In both cases, the reverse-engineered Fabs exhibited identical antigen binding affinity, within error, as Fabs produced from the commercial IgGs. This combination of proteomic and protein engineering techniques provides a useful approach to simplifying the technically challenging process of reverse engineering monoclonal antibodies from protein material. PMID:26852694

  12. Providing a Turn for the Better

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Engineers are tasked with designing new systems every day to meet changing or unexpected technical requirements. After the tragic explosion of the Space Shuttle Challenger on January 28, 1986, NASA engineers embarked on a complete overhaul of many of their long-standing quality systems and procedures. When the official cause of the accident was determined to be an O-ring failure in the right Solid Rocket Booster, NASA's Shuttle Program initiated a thorough redesign of the rocket boosters' clevis ends, which are the O-ring's mating surfaces. One of the unique systems that NASA engineers developed as a result of this effort included a heating assembly that is coupled to the outside of the rocket boosters. When the assembly is affixed to the external surface of the boosters, the very nature of its design allows for the warming of the O-rings prior to launch. After the engineers completed the assembly's design, however, they found that it was nearly impossible to tighten the spanner nuts required for attaching the system, given the minimum amount of clearance they had in the limited and confined space. Under these circumstances, the standard wrenches typically used for tightening these types of nuts did not work, and there were no other existing devices to solve the problem. NASA engineers embraced the challenge, developing a torque wrench tool adapter that allowed for a full rotation of spanner nuts in confined spaces. The tool, which is similar to an open-ended crowfoot wrench and a fixed-face spanner wrench, contains two dowel pins that center and lock the wrench onto the nut.

  13. 40 CFR 86.085-37 - Production vehicles and engines.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... (d) The following definitions apply to this section: (1) Model type means a unique combination of car..., inertia weight, and transmission class. (3) Vehicle configuration means a unique combination of basic engine, engine code, inertia weight, transmission configuration, and axle ratio within a base level. [48...

  14. 40 CFR 86.085-37 - Production vehicles and engines.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    .... (d) The following definitions apply to this section: (1) Model type means a unique combination of car..., inertia weight, and transmission class. (3) Vehicle configuration means a unique combination of basic engine, engine code, inertia weight, transmission configuration, and axle ratio within a base level. [48...

  15. Blended Wing Body Concept Development with Open Rotor Engine Intergration

    NASA Technical Reports Server (NTRS)

    Pitera, David M.; DeHaan, Mark; Brown, Derrell; Kawai, Ronald T.; Hollowell, Steve; Camacho, Peter; Bruns, David; Rawden, Blaine K.

    2011-01-01

    The purpose of this study is to perform a systems analysis of a Blended Wing Body (BWB) open rotor concept at the conceptual design level. This concept will be utilized to estimate overall noise and fuel burn performance, leveraging recent test data. This study will also investigate the challenge of propulsion airframe installation of an open rotor engine on a BWB configuration. Open rotor engines have unique problems relative to turbofans. The rotors are open, exposed to flow conditions outside of the engine. The flow field that the rotors are immersed in may be higher than the free stream flow and it may not be uniform, both of these characteristics could increase noise and decrease performance. The rotors sometimes cause changes in the flow conditions imposed on aircraft surfaces. At high power conditions such as takeoff and climb out, the stream tube of air that goes through the rotors contracts rapidly causing the boundary layer on the body upper surface to go through an adverse pressure gradient which could result with separated airflow. The BWB / Open Rotor configuration must be designed to mitigate these problems.

  16. A Predictive Approach to Network Reverse-Engineering

    NASA Astrophysics Data System (ADS)

    Wiggins, Chris

    2005-03-01

    A central challenge of systems biology is the ``reverse engineering" of transcriptional networks: inferring which genes exert regulatory control over which other genes. Attempting such inference at the genomic scale has only recently become feasible, via data-intensive biological innovations such as DNA microrrays (``DNA chips") and the sequencing of whole genomes. In this talk we present a predictive approach to network reverse-engineering, in which we integrate DNA chip data and sequence data to build a model of the transcriptional network of the yeast S. cerevisiae capable of predicting the response of genes in unseen experiments. The technique can also be used to extract ``motifs,'' sequence elements which act as binding sites for regulatory proteins. We validate by a number of approaches and present comparison of theoretical prediction vs. experimental data, along with biological interpretations of the resulting model. En route, we will illustrate some basic notions in statistical learning theory (fitting vs. over-fitting; cross- validation; assessing statistical significance), highlighting ways in which physicists can make a unique contribution in data- driven approaches to reverse engineering.

  17. Nanoparticles-Based Systems for Osteochondral Tissue Engineering.

    PubMed

    Oliveira, Isabel; Vieira, Sílvia; Oliveira, J Miguel; Reis, Rui L

    2018-01-01

    Osteochondral lesions represent one of the major causes of disabilities in the world. These defects are due to degenerative or inflammatory arthritis, but both affect the articular cartilage and the underlying subchondral bone. Defects from trauma or degenerative pathology frequently cause severe pain, joint deformity, and loss of joint motion. Osteochondral defects are a significant challenge in orthopedic surgery, due to the cartilage complexity and unique structure, as well as its exposure to high pressure and motion. Although there are treatments routinely performed in the clinical practice, they present several limitations. Tissue engineering can be a suitable alternative for osteochondral defects since bone and cartilage engineering had experienced a notable advance over the years. Allied with nanotechnology, osteochondral tissue engineering (OCTE) can be leveled up, being possible to create advanced structures similar to the OC tissue. In this chapter, the current strategies using nanoparticles-based systems are overviewed. The results of the studies herein considered confirm that advanced nanomaterials will undoubtedly play a crucial role in the design of strategies for treatment of osteochondral defects in the near future.

  18. Priorities for a 21st-century defense: aligning u.s. Army environmental science and engineering officer resources with the department of defense strategic guidance.

    PubMed

    Licina, Derek; Rufolo, Dennis; Story, Mike

    2013-01-01

    The recently published Department of Defense (DoD) strategic guidance highlights the need to ?shape a joint force for the future.? Supporting requirements to shape the joint force while the overall DoD force structure is reduced will be challenging. Fortunately, based on its unique training and experience, the Army Environmental Science and Engineering Officer (ESEO) profession is positioned today to fill anticipated joint public health requirements. Obtaining the U.S. Army Medical Department (AMEDD) approval to meet these requirements will have near-term consequences for the ESEO profession as some existing (albeit antiquated) authorizations may go unfilled. However, long-term dividends for the Medical Service Corps (MSC), AMEDD, Army, and DoD will be achieved by realigning critical resources to future joint and interagency requirements. Assigning ESEOs now to organizations such as the Theater Special Operations Commands (TSOCs), U.S. Agency for International Development (USAID), and the North Atlantic Treaty Organization (NATO) with perceived and real joint force health protection/public health requirements through unique means will ensure our profession remains relevant today and supports the joint force of tomorrow. 2013.

  19. Fatty acid biosynthesis revisited: Structure elucidation and metabolic engineering

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

    Beld, Joris; Lee, D. John; Burkart, Michael D.

    Fatty acids are primary metabolites synthesized by complex, elegant, and essential biosynthetic machinery. Fatty acid synthases resemble an iterative assembly line, with an acyl carrier protein conveying the growing fatty acid to necessary enzymatic domains for modification. Each catalytic domain is a unique enzyme spanning a wide range of folds and structures. Although they harbor the same enzymatic activities, two different types of fatty acid synthase architectures are observed in nature. During recent years, strained petroleum supplies have driven interest in engineering organisms to either produce more fatty acids or specific high value products. Such efforts require a fundamental understandingmore » of the enzymatic activities and regulation of fatty acid synthases. Despite more than one hundred years of research, we continue to learn new lessons about fatty acid synthases' many intricate structural and regulatory elements. Lastly, in this review, we summarize each enzymatic domain and discuss efforts to engineer fatty acid synthases, providing some clues to important challenges and opportunities in the field.« less

  20. Designing multifunctional quantum dots for bioimaging, detection, and drug delivery

    PubMed Central

    Zrazhevskiy, Pavel; Sena, Mark; Gao, Xiaohu

    2011-01-01

    The emerging field of bionanotechnology aims at revolutionizing biomedical research and clinical practice via introduction of nanoparticle-based tools, expanding capabilities of existing investigative, diagnostic, and therapeutic techniques as well as creating novel instruments and approaches for addressing challenges faced by medicine. Quantum dots (QDs), semiconductor nanoparticles with unique photo-physical properties, have become one of the dominant classes of imaging probes as well as universal platforms for engineering of multifunctional nanodevices. Possessing versatile surface chemistry and superior optical features, QDs have found initial use in a variety of in vitro and in vivo applications. However, careful engineering of QD probes guided by application-specific design criteria is becoming increasingly important for successful transition of this technology from proof-of-concept studies towards real-life clinical applications. This review outlines the major design principles and criteria, from general ones to application-specific, governing the engineering of novel QD probes satisfying the increasing demands and requirements of nanomedicine and discusses the future directions of QD-focused bionanotechnology research (critical review, 201 references). PMID:20697629

  1. Biodegradable composite scaffolds: a strategy to modulate stem cell behaviour.

    PubMed

    Armentano, Ilaria; Fortunati, Elena; Mattioli, Samantha; Rescignano, Nicolatta; Kenny, José M

    2013-04-01

    The application of new biomaterial technologies offers the potential to direct the stem cell fate, targeting the delivery of cells and reducing immune rejection, thereby supporting the development of regenerative medicine. Cells respond to their surrounding structure and with nanostructures exhibit unique proliferative and differentiation properties. This review presents the relevance, the promising perspectives and challenges of current biodegradable composite scaffolds in terms of material properties, processing technology and surface modification, focusing on significant recent patents in these fields. It has been reported how biodegradable porous composite scaffolds can be engineered with initial properties that reproduce the anisotropy, viscoelasticity, tension-compression non-linearity of different tissues by introducing specific nanostructures. Moreover the modulation of electrical, morphological, surface and topographic scaffold properties enables specific stem cell response. Recent advances in nanotechnology have allowed to engineer novel biomaterials with these complexity levels. Understanding the specific biological response triggered by various aspects of the fibrous environment is important in guiding the design and engineering of novel substrates that mimic the native cell matrix interactions in vivo.

  2. A biomimetic three-dimensional woven composite scaffold for functional tissue engineering of cartilage

    NASA Astrophysics Data System (ADS)

    Moutos, Franklin T.; Freed, Lisa E.; Guilak, Farshid

    2007-02-01

    Tissue engineering seeks to repair or regenerate tissues through combinations of implanted cells, biomaterial scaffolds and biologically active molecules. The rapid restoration of tissue biomechanical function remains an important challenge, emphasizing the need to replicate structural and mechanical properties using novel scaffold designs. Here we present a microscale 3D weaving technique to generate anisotropic 3D woven structures as the basis for novel composite scaffolds that are consolidated with a chondrocyte-hydrogel mixture into cartilage tissue constructs. Composite scaffolds show mechanical properties of the same order of magnitude as values for native articular cartilage, as measured by compressive, tensile and shear testing. Moreover, our findings showed that porous composite scaffolds could be engineered with initial properties that reproduce the anisotropy, viscoelasticity and tension-compression nonlinearity of native articular cartilage. Such scaffolds uniquely combine the potential for load-bearing immediately after implantation in vivo with biological support for cell-based tissue regeneration without requiring cultivation in vitro.

  3. Shuttle Radar Topography Mission (SRTM) Flight System Design and Operations Overview

    NASA Technical Reports Server (NTRS)

    Shen, Yuhsyen; Shaffer, Scott J.; Jordan, Rolando L.

    2000-01-01

    This paper provides an overview of the Shuttle Radar Topography Mission (SRTM), with emphasis on flight system implementation and mission operations from systems engineering perspective. Successfully flown in February, 2000, the SRTM's primary payload consists of several subsystems to form the first spaceborne dual-frequency (C-band and X-band) fixed baseline interferometric synthetic aperture radar (InSAR) system, with the mission objective to acquire data sets over 80% of Earth's landmass for height reconstruction. The paper provides system architecture, unique design features, engineering budgets, design verification, in-flight checkout and data acquisition of the SRTM payload, in particular for the C-band system. Mission operation and post-mission data processing activities are also presented. The complexity of the SRTM as a system, the ambitious mission objective, the demanding requirements and the high interdependency between multi-disciplined subsystems posed many challenges. The engineering experience and the insight thus gained have important implications for future spaceborne interferometric SAR mission design and implementation.

  4. Fatty acid biosynthesis revisited: Structure elucidation and metabolic engineering

    DOE PAGES

    Beld, Joris; Lee, D. John; Burkart, Michael D.

    2014-10-20

    Fatty acids are primary metabolites synthesized by complex, elegant, and essential biosynthetic machinery. Fatty acid synthases resemble an iterative assembly line, with an acyl carrier protein conveying the growing fatty acid to necessary enzymatic domains for modification. Each catalytic domain is a unique enzyme spanning a wide range of folds and structures. Although they harbor the same enzymatic activities, two different types of fatty acid synthase architectures are observed in nature. During recent years, strained petroleum supplies have driven interest in engineering organisms to either produce more fatty acids or specific high value products. Such efforts require a fundamental understandingmore » of the enzymatic activities and regulation of fatty acid synthases. Despite more than one hundred years of research, we continue to learn new lessons about fatty acid synthases' many intricate structural and regulatory elements. Lastly, in this review, we summarize each enzymatic domain and discuss efforts to engineer fatty acid synthases, providing some clues to important challenges and opportunities in the field.« less

  5. SMAP Instrument Mechanical System Engineering

    NASA Technical Reports Server (NTRS)

    Slimko, Eric; French, Richard; Riggs, Benjamin

    2013-01-01

    The Soil Moisture Active Passive (SMAP) mission, scheduled for launch by the end of 2014, is being developed to measure the soil moisture and soil freeze/thaw state on a global scale over a three-year period. The accuracy, resolution, and global coverage of SMAP measurements are invaluable across many science and applications disciplines including hydrology, climate, carbon cycle, and the meteorological, environment, and ecology applications communities. The SMAP observatory is composed of a despun bus and a spinning instrument platform that includes both a deployable 6 meter aperture low structural frequency Astromesh reflector and a spin control system. The instrument section has engendered challenging mechanical system issues associated with the antenna deployment, flexible antenna pointing in the context of a multitude of disturbances, spun section mass properties, spin control system development, and overall integration with the flight system on both mechanical and control system levels. Moreover, the multitude of organizations involved, including two major vendors providing the spin subsystem and reflector boom assembly plus the flight system mechanical and guidance, navigation, and control teams, has led to several unique system engineering challenges. Capturing the key physics associated with the function of the flight system has been challenging due to the many different domains that are applicable. Key interfaces and operational concepts have led to complex negotiations because of the large number of organizations that integrate with the instrument mechanical system. Additionally, the verification and validation concerns associated with the mechanical system have had required far-reaching involvement from both the flight system and other subsystems. The SMAP instrument mechanical systems engineering issues and their solutions are described in this paper.

  6. Visualization of Air Particle Dynamics in an Engine Inertial Particle Separator

    NASA Astrophysics Data System (ADS)

    Wolf, Jason; Zhang, Wei

    2015-11-01

    Unmanned Aerial Vehicles (UAVs) are regularly deployed around the world in support of military, civilian and humanitarian efforts. Due to their unique mission profiles, these advanced UAVs utilize various internal combustion engines, which consume large quantities of air. Operating these UAVs in areas with high concentrations of sand and dust can be hazardous to the engines, especially during takeoff and landing. In such events, engine intake filters quickly become saturated and clogged with dust particles, causing a substantial decrease in the UAVs' engine performance and service life. Development of an Engine Air Particle Separator (EAPS) with high particle separation efficiency is necessary for maintaining satisfactory performance of the UAVs. Inertial Particle Separators (IPS) have been one common effective method but they experience complex internal particle-laden flows that are challenging to understand and model. This research employs an IPS test rig to simulate dust particle separation under different flow conditions. Soda lime glass spheres with a mean diameter of 35-45 microns are used in experiments as a surrogate for airborne particulates encountered during flight. We will present measurements of turbulent flow and particle dynamics using flow visualization techniques to understand the multiphase fluid dynamics in the IPS device. This knowledge can contribute to design better performing IPS systems for UAVs. Cleveland State University, Cleveland, Ohio, 44115.

  7. Benchmarking Gas Path Diagnostic Methods: A Public Approach

    NASA Technical Reports Server (NTRS)

    Simon, Donald L.; Bird, Jeff; Davison, Craig; Volponi, Al; Iverson, R. Eugene

    2008-01-01

    Recent technology reviews have identified the need for objective assessments of engine health management (EHM) technology. The need is two-fold: technology developers require relevant data and problems to design and validate new algorithms and techniques while engine system integrators and operators need practical tools to direct development and then evaluate the effectiveness of proposed solutions. This paper presents a publicly available gas path diagnostic benchmark problem that has been developed by the Propulsion and Power Systems Panel of The Technical Cooperation Program (TTCP) to help address these needs. The problem is coded in MATLAB (The MathWorks, Inc.) and coupled with a non-linear turbofan engine simulation to produce "snap-shot" measurements, with relevant noise levels, as if collected from a fleet of engines over their lifetime of use. Each engine within the fleet will experience unique operating and deterioration profiles, and may encounter randomly occurring relevant gas path faults including sensor, actuator and component faults. The challenge to the EHM community is to develop gas path diagnostic algorithms to reliably perform fault detection and isolation. An example solution to the benchmark problem is provided along with associated evaluation metrics. A plan is presented to disseminate this benchmark problem to the engine health management technical community and invite technology solutions.

  8. LLIMAS: Revolutionizing integrating modeling and analysis at MIT Lincoln Laboratory

    NASA Astrophysics Data System (ADS)

    Doyle, Keith B.; Stoeckel, Gerhard P.; Rey, Justin J.; Bury, Mark E.

    2017-08-01

    MIT Lincoln Laboratory's Integrated Modeling and Analysis Software (LLIMAS) enables the development of novel engineering solutions for advanced prototype systems through unique insights into engineering performance and interdisciplinary behavior to meet challenging size, weight, power, environmental, and performance requirements. LLIMAS is a multidisciplinary design optimization tool that wraps numerical optimization algorithms around an integrated framework of structural, thermal, optical, stray light, and computational fluid dynamics analysis capabilities. LLIMAS software is highly extensible and has developed organically across a variety of technologies including laser communications, directed energy, photometric detectors, chemical sensing, laser radar, and imaging systems. The custom software architecture leverages the capabilities of existing industry standard commercial software and supports the incorporation of internally developed tools. Recent advances in LLIMAS's Structural-Thermal-Optical Performance (STOP), aeromechanical, and aero-optical capabilities as applied to Lincoln prototypes are presented.

  9. The design of an air-cooled metallic high temperature radial turbine

    NASA Technical Reports Server (NTRS)

    Snyder, Philip H.; Roelke, Richard J.

    1988-01-01

    Recent trends in small advanced gas turbine engines call for higher turbine inlet temperatures. Advances in radial turbine technology have opened the way for a cooled metallic radial turbine capable of withstanding turbine inlet temperatures of 2500 F while meeting the challenge of high efficiency in this small flow size range. In response to this need, a small air-cooled radial turbine has been designed utilizing internal blade coolant passages. The coolant flow passage design is uniquely tailored to simultaneously meet rotor cooling needs and rotor fabrication constraints. The rotor flow-path design seeks to realize improved aerodynamic blade loading characteristics and high efficiency while satisfying rotor life requirements. An up-scaled version of the final engine rotor is currently under fabrication and, after instrumentation, will be tested in the warm turbine test facility at the NASA Lewis Research Center.

  10. Reduced Noise Gas Turbine Engine System and Supersonic Exhaust Nozzle System Using Elector to Entrain Ambient Air

    NASA Technical Reports Server (NTRS)

    Sokhey, Jagdish S. (Inventor); Pierluissi, Anthony F. (Inventor)

    2017-01-01

    One embodiment of the present invention is a unique gas turbine engine system. Another embodiment is a unique exhaust nozzle system for a gas turbine engine. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for gas turbine engine systems and exhaust nozzle systems for gas turbine engines. Further embodiments, forms, features, aspects, benefits, and advantages of the present application will become apparent from the description and figures provided herewith.

  11. Pulp regeneration in a full-length human tooth root using a hierarchical nanofibrous microsphere system.

    PubMed

    Li, Xiangwei; Ma, Chi; Xie, Xiaohua; Sun, Hongchen; Liu, Xiaohua

    2016-04-15

    While pulp regeneration using tissue engineering strategy has been explored for over a decade, successful regeneration of pulp tissues in a full-length human root with a one-end seal that truly simulates clinical endodontic treatment has not been achieved. To address this challenge, we designed and synthesized a unique hierarchical growth factor-loaded nanofibrous microsphere scaffolding system. In this system, vascular endothelial growth factor (VEGF) binds with heparin and is encapsulated in heparin-conjugated gelatin nanospheres, which are further immobilized in the nanofibers of an injectable poly(l-lactic acid) (PLLA) microsphere. This hierarchical microsphere system not only protects the VEGF from denaturation and degradation, but also provides excellent control of its sustained release. In addition, the nanofibrous PLLA microsphere integrates the extracellular matrix-mimicking architecture with a highly porous injectable form, efficiently accommodating dental pulp stem cells (DPSCs) and supporting their proliferation and pulp tissue formation. Our in vivo study showed the successful regeneration of pulp-like tissues that fulfilled the entire apical and middle thirds and reached the coronal third of the full-length root canal. In addition, a large number of blood vessels were regenerated throughout the canal. For the first time, our work demonstrates the success of pulp tissue regeneration in a full-length root canal, making it a significant step toward regenerative endodontics. The regeneration of pulp tissues in a full-length tooth root canal has been one of the greatest challenges in the field of regenerative endodontics, and one of the biggest barriers for its clinical application. In this study, we developed a unique approach to tackle this challenge, and for the first time, we successfully regenerated living pulp tissues in a full-length root canal, making it a significant step toward regenerative endodontics. This study will make positive scientific impact and interest the broad and multidisciplinary readership in the dental biomaterials and craniofacial tissue engineering community. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

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

    Michael Viola, J. Edwards, T. Brown, L. Dudek, R. Ellis, P. Heitzenroeder, R. Strykowsky and Michael Cole

    The National Compact Stellarator Experiment (NCSX) was a collaborative effort between ORNL and PPPL. PPPL provided the assembly techniques with guidance from ORNL to meet design criteria. The individual vacuum vessel segments, modular coils, trim coils, and toroidal field coils components were delivered to the Field Period Assembly (FPA) crew who then would complete the component assemblies and then assemble the final three field period assemblies, each consisting of two sets of three modular coils assembled over a 120o vacuum vessel segment with the trim coils and toroidal field coils providing the outer layer. The requirements for positioning the modularmore » coils were found to be most demanding. The assembly tolerances required for accurate positioning of the field coil windings in order to generate sufficiently accurate magnetic fields strained state of the art techniques in metrology and alignment and required constant monitoring of assembly steps with laser trackers, measurement arms, and photogrammetry. The FPA activities were being performed concurrently while engineering challenges were being resolved. For example, it was determined that high friction electrically isolated shims were needed between the modular coil interface joints and low distortion welding was required in the nose region of those joints. This took months of analysis and development yet the assembly was not significantly impacted because other assembly tasks could be performed in parallel with ongoing assembly tasks as well as tasks such as advance tooling setup preparation for the eventual welding tasks. The crew technicians developed unique, accurate time saving techniques and tooling which provided significant cost and schedule savings. Project management displayed extraordinary foresight and every opportunity to gain advanced knowledge and develop techniques was taken advantage of. Despite many risk concerns, the cost and schedule performance index was maintained nearly 1.0 during the assembly phase until project cancellation. In this paper, the assembly logic, the engineering challenges, solutions to those challenges and some of the unique and clever assembly techniques, will be presented.« less

  13. p21-activated kinase inhibitors.

    PubMed

    Rudolph, Joachim; Crawford, James J; Hoeflich, Klaus P; Chernoff, Jonathan

    2013-01-01

    The p21-activated kinases (PAKs) are Ser/Thr kinases in the STE20 kinase family with important roles in regulating cytoskeletal organization, cell migration, and signaling. The PAK enzyme family comprises six members subdivided into two groups: Group I, represented by PAK1, 2, and 3, and Group II, represented by PAK 4, 5, and 6, based on sequence and structural homology. Individual PAK isoforms were found to be overexpressed and amplified in a variety of human cancers, and in vitro and in vivo studies using genetically engineered systems as well as small-molecule tool compounds have suggested therapeutic utility of PAKs as oncology targets. The identification of potent and kinome-selective ATP-competitive PAK inhibitors has proven challenging, likely caused by the openness and unique plasticity of the ATP-binding site of PAK enzymes. Progress in achieving increased kinase selectivity has been achieved with certain inhibitors but at the expense of increased molecular weight. Allosteric inhibitors, such as IPA-3, leverage the unique Group I PAK autoregulatory domain for selective inhibition, and this approach might provide an outlet to evade the kinase selectivity challenges observed with ATP-competitive PAK inhibitors. © 2013 Elsevier Inc. All rights reserved.

  14. External Tank Program Legacy of Success

    NASA Technical Reports Server (NTRS)

    Welzyn, Ken; Pilet, Jeff

    2010-01-01

    I.Goal: a) Extensive TPS damage caused by extreme hail storm. b) Repair plan required to restore TPS to minimize program manifest impacts. II. Challenges: a) Skeptical technical community - Concerned about interactions of damage with known/unknown failure modes. b) Schedule pressure to accommodate ISS program- Next tank still at MAF c)Limited ET resources. III. How d We Do It?: a) Developed unique engineering requirements and tooling to minimize repairs. b) Performed large amount of performance testing to demonstrate understanding of repairs and residual conditions. c) Effectively communicated results to technical community and management to instill confidence in expected performance.

  15. Modeling Tools Predict Flow in Fluid Dynamics

    NASA Technical Reports Server (NTRS)

    2010-01-01

    "Because rocket engines operate under extreme temperature and pressure, they present a unique challenge to designers who must test and simulate the technology. To this end, CRAFT Tech Inc., of Pipersville, Pennsylvania, won Small Business Innovation Research (SBIR) contracts from Marshall Space Flight Center to develop software to simulate cryogenic fluid flows and related phenomena. CRAFT Tech enhanced its CRUNCH CFD (computational fluid dynamics) software to simulate phenomena in various liquid propulsion components and systems. Today, both government and industry clients in the aerospace, utilities, and petrochemical industries use the software for analyzing existing systems as well as designing new ones."

  16. iSTEM: The Aerospace Engineering Challenge

    ERIC Educational Resources Information Center

    English, Lyn D.; King, Donna T.; Hudson, Peter; Dawes, Les

    2014-01-01

    The authors developed The Paper Plane Challenge as one of a three-part response to The Aerospace Engineering Challenge. The Aerospace Engineering Challenge was the second of three multi-part activities that they had developed with the teachers during the year. Their aim was to introduce students to the exciting world of engineering, where they…

  17. Eight-dimensional methodology for innovative thinking about the case and ethics of the Mount Graham, Large Binocular Telescope project.

    PubMed

    Berne, Rosalyn W; Raviv, Daniel

    2004-04-01

    This paper introduces the Eight Dimensional Methodology for Innovative Thinking (the Eight Dimensional Methodology), for innovative problem solving, as a unified approach to case analysis that builds on comprehensive problem solving knowledge from industry, business, marketing, math, science, engineering, technology, arts, and daily life. It is designed to stimulate innovation by quickly generating unique "out of the box" unexpected and high quality solutions. It gives new insights and thinking strategies to solve everyday problems faced in the workplace, by helping decision makers to see otherwise obscure alternatives and solutions. Daniel Raviv, the engineer who developed the Eight Dimensional Methodology, and paper co-author, technology ethicist Rosalyn Berne, suggest that this tool can be especially useful in identifying solutions and alternatives for particular problems of engineering, and for the ethical challenges which arise with them. First, the Eight Dimensional Methodology helps to elucidate how what may appear to be a basic engineering problem also has ethical dimensions. In addition, it offers to the engineer a methodology for penetrating and seeing new dimensions of those problems. To demonstrate the effectiveness of the Eight Dimensional Methodology as an analytical tool for thinking about ethical challenges to engineering, the paper presents the case of the construction of the Large Binocular Telescope (LBT) on Mount Graham in Arizona. Analysis of the case offers to decision makers the use of the Eight Dimensional Methodology in considering alternative solutions for how they can proceed in their goals of exploring space. It then follows that same process through the second stage of exploring the ethics of each of those different solutions. The LBT project pools resources from an international partnership of universities and research institutes for the construction and maintenance of a highly sophisticated, powerful new telescope. It will soon mark the erection of the world's largest and most powerful optical telescope, designed to see fine detail otherwise visible only from space. It also represents a controversial engineering project that is being undertaken on land considered to be sacred by the local, native Apache people. As presented, the case features the University of Virginia, and its challenges in consideration of whether and how to join the LBT project consortium.

  18. When small is better than BIG

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

    McDaniel, Hunter; Beard, Matthew C; Wheeler, Lance M

    Representing the Center for Advanced Solar Photophysics (CASP), this document is one of the entries in the Ten Hundred and One Word Challenge and was awarded “Overall Winner Runner-up and People’s Choice Winner.” As part of the challenge, the 46 Energy Frontier Research Centers were invited to represent their science in images, cartoons, photos, words and original paintings, but any descriptions or words could only use the 1000 most commonly used words in the English language, with the addition of one word important to each of the EFRCs and the mission of DOE: energy. The mission of CASP is tomore » explore and exploit the unique physics of nanostructured materials to boost the efficiency of solar energy conversion through novel light-matter interactions, controlled excited-state dynamics, and engineered carrier-carrier coupling.« less

  19. Nuclear instrumentation and measurement: a review based on the ANIMMA conferences

    NASA Astrophysics Data System (ADS)

    Giot, Michel; Vermeeren, Ludo; Lyoussi, Abdallah; Reynard-Carette, Christelle; Lhuillier, Christian; Mégret, Patrice; Deconinck, Frank; Gonçalves, Bruno Soares

    2017-12-01

    The ANIMMA conferences offer a unique opportunity to discover research carried out in all fields of nuclear measurements and instrumentation with applications extending from fundamental physics to fission and fusion reactors, medical imaging, environmental protection and homeland security. After four successful editions of the Conference, it was decided to prepare a review based to a large extent but not exclusively on the papers presented during the first four editions of the conference. This review is organized according to the measurement methodologies: neutronic, photonic, thermal, acoustic and optical measurements, as well as medical imaging and specific challenges linked to data acquisition and electronic hardening. The paper describes the main challenges justifying research in these different areas, and summarizes the recent progress reported. It offers researchers and engineers a way to quickly and efficiently access knowledge in highly specialized areas.

  20. Influence of dissolved organic matter on the environmental fate of metals, nanoparticles, and colloids

    USGS Publications Warehouse

    Aiken, George R.; Hsu-Kim, Heileen; Ryan, Joseph N.

    2011-01-01

    We have known for decades that dissolved organic matter (DOM) plays a critical role in the biogeochemical cycling of trace metals and the mobility of colloidal particles in aquatic environments. In recent years, concerns about the ecological and human health effects of metal-based engineered nanoparticles released into natural waters have increased efforts to better define the nature of DOM interactions with metals and surfaces. Nanomaterials exhibit unique properties and enhanced reactivities that are not apparent in larger materials of the same composition1,2 or dissolved ions of metals that comprise the nanoparticles. These nanoparticle-specific properties generally result from the relatively large proportion of the atoms located at the surface, which leads to very high specific surface areas and a high proportion of crystal lattice imperfections relative to exposed surface area. Nanoscale colloids are ubiquitous in nature,2 and many engineered nanomaterials have analogs in the natural world. The properties of these materials, whether natural or manmade, are poorly understood, and new challenges have been presented in assessing their environmental fate. These challenges are particularly relevant in aquatic environments where interactions with DOM are key, albeit often overlooked, moderators of reactivity at the molecular and nanocolloidal scales.

  1. Training and Mentoring the Next Generation of Scientists and Engineers to Secure Continuity and Successes of the US DOE's Environmental Remediation Efforts - 13387

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

    Lagos, L.

    The DOE Office of Environmental Management (DOE-EM) oversees one of the largest and most technically challenging cleanup programs in the world. The mission of DOE-EM is to complete the safe cleanup of the environmental legacy from five decades of nuclear weapons development and government-sponsored nuclear energy research. Since 1995, Florida International University's Applied Research Center (FIU-ARC) has supported the DOE-EM mission and provided unique research capabilities to address some of these highly technical and difficult challenges. This partnership has allowed FIU-ARC to create a unique infrastructure that is critical for the training and mentoring of science, technology, engineering, and mathmore » (STEM) students and has exposed many STEM students to 'hands-on' DOE-EM applied research, supervised by the scientists and engineers at ARC. As a result of this successful partnership between DOE and FIU, DOE requested FIU-ARC to create the DOE-FIU Science and Technology Workforce Development Initiative in 2007. This innovative program was established to create a 'pipeline' of minority STEM students trained and mentored to enter DOE's environmental cleanup workforce. The program was designed to help address DOE's future workforce needs by partnering with academic, government and private companies (DOE contractors) to mentor future minority scientists and engineers in the research, development, and deployment of new technologies and processes addressing DOE's environmental cleanup challenges. Since its inception in 2007, the program has trained and mentored 78 FIU STEM minority students. Although, the program has been in existence for only five years, a total of 75 internships have been conducted at DOE National Laboratories, DOE sites, DOE Headquarters and field offices, and DOE contractors. Over 85 DOE Fellows have participated in the Waste Management Symposia since 2008 with a total of 68 student posters and 7 oral presentations given at WM. The DOE Fellows participation at WM has resulted in three Best Student Poster Awards (WM09, WM10, and WM11) and one Best Professional Poster Award (WM09). DOE Fellows have also presented their research at ANS DD and R and ANS Robotics Topical meetings. Moreover, several of our DOE Fellows have already obtained employment with DOE-EM, other federal agencies, DOE contractors. This paper will discuss how DOE Fellows program is training and mentoring FIU STEM students in Department of Energy's Office of Environmental Management technical challenges and research. This training and mentoring has resulted in the development of well trained and polished young scientists and engineers that will become the future workforce in charge of carrying on DOE-EM's environmental cleanup mission. The paper will showcase FIU's DOE Fellows model and highlight some of the applied research the DOE Fellows have conducted at FIU's Applied Research Center and across the Complex by participating in summer internship assignments. This paper will also present and highlight other Fellowships and internships programs sponsored by National Nuclear Security Agency (NNSA), DOE-EM, NRC, Energy (NE), and other federal agencies targeting workforce development. (authors)« less

  2. Low-Cost Approach to the Design and Fabrication of a LOX/RP-1 Injector

    NASA Technical Reports Server (NTRS)

    Shadoan, Michael D.; Sparks, Dave L.; Turner, James E. (Technical Monitor)

    2000-01-01

    NASA Marshall Space Flight Center (MSFC) has designed, built, and is currently testing Fastrac, a liquid oxygen (LOX)/RP-1 fueled 60K-lb thrust class rocket engine. One facet of Fastrac, which makes it unique is that it is the first large-scale engine designed and developed in accordance with the Agency's mandated "faster, better, cheaper" (FBC) program policy. The engine was developed under the auspices of MSFC's Low Cost Boost Technology office. Development work for the main injector actually began in 1993 in subscale form. In 1996, work began on the full-scale unit approximately 1 year prior to initiation of the engine development program. In order to achieve the value goals established by the FBC policy, a review of traditional design practices was necessary. This internal reevaluation would ultimately challenge more conventional methods of material selection. design process, and fabrication techniques. The effort was highly successful. This "new way" of thinking has resulted in an innovative injector design, one with reduced complexity and significantly lower cost. Application of lessons learned during this effort to new or existing designs can have a similar effect on costs and future program successes.

  3. Towards Requirements in Systems Engineering for Aerospace IVHM Design

    NASA Technical Reports Server (NTRS)

    Saxena, Abhinav; Roychoudhury, Indranil; Lin, Wei; Goebel, Kai

    2013-01-01

    Health management (HM) technologies have been employed for safety critical system for decades, but a coherent systematic process to integrate HM into the system design is not yet clear. Consequently, in most cases, health management resorts to be an after-thought or 'band-aid' solution. Moreover, limited guidance exists for carrying out systems engineering (SE) on the subject of writing requirements for designs with integrated vehicle health management (IVHM). It is well accepted that requirements are key to developing a successful IVHM system right from the concept stage to development, verification, utilization, and support. However, writing requirements for systems with IVHM capability have unique challenges that require the designers to look beyond their own domains and consider the constraints and specifications of other interlinked systems. In this paper we look at various stages in the SE process and identify activities specific to IVHM design and development. More importantly, several relevant questions are posed that system engineers must address at various design and development stages. Addressing these questions should provide some guidance to systems engineers towards writing IVHM related requirements to ensure that appropriate IVHM functions are built into the system design.

  4. Metabolic engineering in chemolithoautotrophic hosts for the production of fuels and chemicals.

    PubMed

    Nybo, S Eric; Khan, Nymul E; Woolston, Benjamin M; Curtis, Wayne R

    2015-07-01

    The ability of autotrophic organisms to fix CO2 presents an opportunity to utilize this 'greenhouse gas' as an inexpensive substrate for biochemical production. Unlike conventional heterotrophic microorganisms that consume carbohydrates and amino acids, prokaryotic chemolithoautotrophs have evolved the capacity to utilize reduced chemical compounds to fix CO2 and drive metabolic processes. The use of chemolithoautotrophic hosts as production platforms has been renewed by the prospect of metabolically engineered commodity chemicals and fuels. Efforts such as the ARPA-E electrofuels program highlight both the potential and obstacles that chemolithoautotrophic biosynthetic platforms provide. This review surveys the numerous advances that have been made in chemolithoautotrophic metabolic engineering with a focus on hydrogen oxidizing bacteria such as the model chemolithoautotrophic organism (Ralstonia), the purple photosynthetic bacteria (Rhodobacter), and anaerobic acetogens. Two alternative strategies of microbial chassis development are considered: (1) introducing or enhancing autotrophic capabilities (carbon fixation, hydrogen utilization) in model heterotrophic organisms, or (2) improving tools for pathway engineering (transformation methods, promoters, vectors etc.) in native autotrophic organisms. Unique characteristics of autotrophic growth as they relate to bioreactor design and process development are also discussed in the context of challenges and opportunities for genetic manipulation of organisms as production platforms. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  5. The James Webb Space Telescope RealWorld-InWorld Design Challenge: Involving Professionals in a Virtual Classroom

    NASA Astrophysics Data System (ADS)

    Masetti, Margaret; Bowers, S.

    2011-01-01

    Students around the country are becoming experts on the James Webb Space Telescope by designing solutions to two of the design challenges presented by this complex mission. RealWorld-InWorld has two parts; the first (the Real World portion) has high-school students working face to face in their classroom as engineers and scientists. The InWorld phase starts December 15, 2010 as interested teachers and their teams of high school students register to move their work into a 3D multi-user virtual world environment. At the start of this phase, college students from all over the country choose a registered team to lead InWorld. Each InWorld team is also assigned an engineer or scientist mentor. In this virtual world setting, each team refines their design solutions and creates a 3D model of the Webb telescope. InWorld teams will use 21st century tools to collaborate and build in the virtual world environment. Each team will learn, not only from their own team members, but will have the opportunity to interact with James Webb Space Telescope researchers through the virtual world setting, which allows for synchronous interactions. Halfway through the challenge, design solutions will be critiqued and a mystery problem will be introduced for each team. The top five teams will be invited to present their work during a synchronous Education Forum April 14, 2011. The top team will earn scholarships and technology. This is an excellent opportunity for professionals in both astronomy and associated engineering disciplines to become involved with a unique educational program. Besides the chance to mentor a group of interested students, there are many opportunities to interact with the students as a guest, via chats and presentations.

  6. Technology Transfer Challenges: A Case Study of User-Centered Design in NASA's Systems Engineering Culture

    NASA Technical Reports Server (NTRS)

    Quick, Jason

    2009-01-01

    The Upper Stage (US) section of the National Aeronautics and Space Administration's (NASA) Ares I rocket will require internal access platforms for maintenance tasks performed by humans inside the vehicle. Tasks will occur during expensive critical path operations at Kennedy Space Center (KSC) including vehicle stacking and launch preparation activities. Platforms must be translated through a small human access hatch, installed in an enclosed worksite environment, support the weight of ground operators and be removed before flight - and their design must minimize additional vehicle mass at attachment points. This paper describes the application of a user-centered conceptual design process and the unique challenges encountered within NASA's systems engineering culture focused on requirements and "heritage hardware". The NASA design team at Marshall Space Flight Center (MSFC) initiated the user-centered design process by studying heritage internal access kits and proposing new design concepts during brainstorming sessions. Simultaneously, they partnered with the Technology Transfer/Innovative Partnerships Program to research inflatable structures and dynamic scaffolding solutions that could enable ground operator access. While this creative, technology-oriented exploration was encouraged by upper management, some design stakeholders consistently opposed ideas utilizing novel, untested equipment. Subsequent collaboration with an engineering consulting firm improved the technical credibility of several options, however, there was continued resistance from team members focused on meeting system requirements with pre-certified hardware. After a six-month idea-generating phase, an intensive six-week effort produced viable design concepts that justified additional vehicle mass while optimizing the human factors of platform installation and use. Although these selected final concepts closely resemble heritage internal access platforms, challenges from the application of the user-centered process provided valuable lessons for improving future collaborative conceptual design efforts.

  7. Review of Nuclear Thermal Propulsion Ground Test Options

    NASA Technical Reports Server (NTRS)

    Coote, David J.; Power, Kevin P.; Gerrish, Harold P.; Doughty, Glen

    2015-01-01

    High efficiency rocket propulsion systems are essential for humanity to venture beyond the moon. Nuclear Thermal Propulsion (NTP) is a promising alternative to conventional chemical rockets with relatively high thrust and twice the efficiency of highest performing chemical propellant engines. NTP utilizes the coolant of a nuclear reactor to produce propulsive thrust. An NTP engine produces thrust by flowing hydrogen through a nuclear reactor to cool the reactor, heating the hydrogen and expelling it through a rocket nozzle. The hot gaseous hydrogen is nominally expected to be free of radioactive byproducts from the nuclear reactor; however, it has the potential to be contaminated due to off-nominal engine reactor performance. NTP ground testing is more difficult than chemical engine testing since current environmental regulations do not allow/permit open air testing of NTP as was done in the 1960's and 1970's for the Rover/NERVA program. A new and innovative approach to rocket engine ground test is required to mitigate the unique health and safety risks associated with the potential entrainment of radioactive waste from the NTP engine reactor core into the engine exhaust. Several studies have been conducted since the ROVER/NERVA program in the 1970's investigating NTP engine ground test options to understand the technical feasibility, identify technical challenges and associated risks and provide rough order of magnitude cost estimates for facility development and test operations. The options can be divided into two distinct schemes; (1) real-time filtering of the engine exhaust and its release to the environment or (2) capture and storage of engine exhaust for subsequent processing.

  8. Graphene and its derivatives as biomedical materials: future prospects and challenges.

    PubMed

    Banerjee, Arghya Narayan

    2018-06-06

    Graphene and its derivatives possess some intriguing properties, which generates tremendous interests in various fields, including biomedicine. The biomedical applications of graphene-based nanomaterials have attracted great interests over the last decade, and several groups have started working on this field around the globe. Because of the excellent biocompatibility, solubility and selectivity, graphene and its derivatives have shown great potential as biosensing and bio-imaging materials. Also, due to some unique physico-chemical properties of graphene and its derivatives, such as large surface area, high purity, good bio-functionalizability, easy solubility, high drug loading capacity, capability of easy cell membrane penetration, etc., graphene-based nanomaterials become promising candidates for bio-delivery carriers. Besides, graphene and its derivatives have also shown interesting applications in the fields of cell-culture, cell-growth and tissue engineering. In this article, a comprehensive review on the applications of graphene and its derivatives as biomedical materials has been presented. The unique properties of graphene and its derivatives (such as graphene oxide, reduced graphene oxide, graphane, graphone, graphyne, graphdiyne, fluorographene and their doped versions) have been discussed, followed by discussions on the recent efforts on the applications of graphene and its derivatives in biosensing, bio-imaging, drug delivery and therapy, cell culture, tissue engineering and cell growth. Also, the challenges involved in the use of graphene and its derivatives as biomedical materials are discussed briefly, followed by the future perspectives of the use of graphene-based nanomaterials in bio-applications. The review will provide an outlook to the applications of graphene and its derivatives, and may open up new horizons to inspire broader interests across various disciplines.

  9. Advantages and Challenges of Relaxor-PbTiO3 Ferroelectric Crystals for Electroacoustic Transducers- A Review.

    PubMed

    Zhang, Shujun; Li, Fei; Jiang, Xiaoning; Kim, Jinwook; Luo, Jun; Geng, Xuecang

    2015-03-01

    Relaxor-PbTiO 3 (PT) based ferroelectric crystals with the perovskite structure have been investigated over the last few decades due to their ultrahigh piezoelectric coefficients ( d 33 > 1500 pC/N) and electromechanical coupling factors ( k 33 > 90%), far outperforming state-of-the-art ferroelectric polycrystalline Pb(Zr,Ti)O 3 ceramics, and are at the forefront of advanced electroacoustic applications. In this review, the performance merits of relaxor-PT crystals in various electroacoustic devices are presented from a piezoelectric material viewpoint. Opportunities come from not only the ultrahigh properties, specifically coupling and piezoelectric coefficients, but through novel vibration modes and crystallographic/domain engineering. Figure of merits (FOMs) of crystals with various compositions and phases were established for various applications, including medical ultrasonic transducers, underwater transducers, acoustic sensors and tweezers. For each device application, recent developments in relaxor-PT ferroelectric crystals were surveyed and compared with state-of-the-art polycrystalline piezoelectrics, with an emphasis on their strong anisotropic features and crystallographic uniqueness, including engineered domain - property relationships. This review starts with an introduction on electroacoustic transducers and the history of piezoelectric materials. The development of the high performance relaxor-PT single crystals, with a focus on their uniqueness in transducer applications, is then discussed. In the third part, various FOMs of piezoelectric materials for a wide range of ultrasound applications, including diagnostic ultrasound, therapeutic ultrasound, underwater acoustic and passive sensors, tactile sensors and acoustic tweezers, are evaluated to provide a thorough understanding of the materials' behavior under operational conditions. Structure-property-performance relationships are then established. Finally, the impacts and challenges of relaxor-PT crystals are summarized to guide on-going and future research in the development of relaxor-PT crystals for the next generation electroacoustic transducers.

  10. Advantages and Challenges of Relaxor-PbTiO3 Ferroelectric Crystals for Electroacoustic Transducers- A Review

    PubMed Central

    Zhang, Shujun; Li, Fei; Jiang, Xiaoning; Kim, Jinwook; Luo, Jun; Geng, Xuecang

    2014-01-01

    Relaxor-PbTiO3 (PT) based ferroelectric crystals with the perovskite structure have been investigated over the last few decades due to their ultrahigh piezoelectric coefficients (d33 > 1500 pC/N) and electromechanical coupling factors (k33 > 90%), far outperforming state-of-the-art ferroelectric polycrystalline Pb(Zr,Ti)O3 ceramics, and are at the forefront of advanced electroacoustic applications. In this review, the performance merits of relaxor-PT crystals in various electroacoustic devices are presented from a piezoelectric material viewpoint. Opportunities come from not only the ultrahigh properties, specifically coupling and piezoelectric coefficients, but through novel vibration modes and crystallographic/domain engineering. Figure of merits (FOMs) of crystals with various compositions and phases were established for various applications, including medical ultrasonic transducers, underwater transducers, acoustic sensors and tweezers. For each device application, recent developments in relaxor-PT ferroelectric crystals were surveyed and compared with state-of-the-art polycrystalline piezoelectrics, with an emphasis on their strong anisotropic features and crystallographic uniqueness, including engineered domain - property relationships. This review starts with an introduction on electroacoustic transducers and the history of piezoelectric materials. The development of the high performance relaxor-PT single crystals, with a focus on their uniqueness in transducer applications, is then discussed. In the third part, various FOMs of piezoelectric materials for a wide range of ultrasound applications, including diagnostic ultrasound, therapeutic ultrasound, underwater acoustic and passive sensors, tactile sensors and acoustic tweezers, are evaluated to provide a thorough understanding of the materials’ behavior under operational conditions. Structure-property-performance relationships are then established. Finally, the impacts and challenges of relaxor-PT crystals are summarized to guide on-going and future research in the development of relaxor-PT crystals for the next generation electroacoustic transducers. PMID:25530641

  11. Usability research study of a specially engineered sonic powered toothbrush with unique sensing and control technologies.

    PubMed

    Hunter, Gail; Burns, Laurie; Bone, Brian; Mintel, Thomas; Jimenez, Eduardo

    2012-01-01

    This paper summarizes the results of a longitudinal usability research study of a specially engineered sonic powered toothbrush with unique sensing and control technologies. The usability test was conducted with fourteen (14) consumers from the St. Louis, MO, USA area who use manual toothbrushes. The study consisted of consumers using the specially engineered sonic powered toothbrush with unique sensing and control technologies for three weeks. During the study, users participated in four toothbrush trials during weekly visits to the research facility. These trials were videotaped and were analyzed regarding brushing time, behavior, and technique. In addition, the users were required to use the toothbrush twice a day for their at-home brushing. The toothbrush had a positive impact on consumers' tooth brushing behavior. Users spent more time brushing their teeth with this toothbrush as compared to their manual toothbrush. In addition, users spent more time keeping the sonic toothbrush in the recommended angle during use. Finally, users perceived their teeth to be cleaner when using the specially engineered sonic powered toothbrush with unique sensing and control technologies. The specially engineered sonic powered toothbrush with unique sensing and control technologies left a positive impression on the users. The users perceived the toothbrush to clean their teeth better than a manual toothbrush.

  12. Deep sequencing in library selection projects: what insight does it bring?

    PubMed

    Glanville, J; D'Angelo, S; Khan, T A; Reddy, S T; Naranjo, L; Ferrara, F; Bradbury, A R M

    2015-08-01

    High throughput sequencing is poised to change all aspects of the way antibodies and other binders are discovered and engineered. Millions of available sequence reads provide an unprecedented sampling depth able to guide the design and construction of effective, high quality naïve libraries containing tens of billions of unique molecules. Furthermore, during selections, high throughput sequencing enables quantitative tracing of enriched clones and position-specific guidance to amino acid variation under positive selection during antibody engineering. Successful application of the technologies relies on specific PCR reagent design, correct sequencing platform selection, and effective use of computational tools and statistical measures to remove error, identify antibodies, estimate diversity, and extract signatures of selection from the clone down to individual structural positions. Here we review these considerations and discuss some of the remaining challenges to the widespread adoption of the technology. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Surface engineering of graphene-based nanomaterials for biomedical applications.

    PubMed

    Shi, Sixiang; Chen, Feng; Ehlerding, Emily B; Cai, Weibo

    2014-09-17

    Graphene-based nanomaterials have attracted tremendous interest over the past decade due to their unique electronic, optical, mechanical, and chemical properties. However, the biomedical applications of these intriguing nanomaterials are still limited due to their suboptimal solubility/biocompatibility, potential toxicity, and difficulties in achieving active tumor targeting, just to name a few. In this Topical Review, we will discuss in detail the important role of surface engineering (i.e., bioconjugation) in improving the in vitro/in vivo stability and enriching the functionality of graphene-based nanomaterials, which can enable single/multimodality imaging (e.g., optical imaging, positron emission tomography, magnetic resonance imaging) and therapy (e.g., photothermal therapy, photodynamic therapy, and drug/gene delivery) of cancer. Current challenges and future research directions are also discussed and we believe that graphene-based nanomaterials are attractive nanoplatforms for a broad array of future biomedical applications.

  14. Deep sequencing in library selection projects: what insight does it bring?

    PubMed Central

    Glanville, J; D’Angelo, S; Khan, T.A.; Reddy, S. T.; Naranjo, L.; Ferrara, F.; Bradbury, A.R.M.

    2015-01-01

    High throughput sequencing is poised to change all aspects of the way antibodies and other binders are discovered and engineered. Millions of available sequence reads provide an unprecedented sampling depth able to guide the design and construction of effective, high quality naïve libraries containing tens of billions of unique molecules. Furthermore, during selections, high throughput sequencing enables quantitative tracing of enriched clones and position-specific guidance to amino acid variation under positive selection during antibody engineering. Successful application of the technologies relies on specific PCR reagent design, correct sequencing platform selection, and effective use of computational tools and statistical measures to remove error, identify antibodies, estimate diversity, and extract signatures of selection from the clone down to individual structural positions. Here we review these considerations and discuss some of the remaining challenges to the widespread adoption of the technology. PMID:26451649

  15. Stable Metal–Organic Frameworks with Group 4 Metals: Current Status and Trends

    PubMed Central

    2018-01-01

    Group 4 metal-based metal–organic frameworks (MIV-MOFs), including Ti-, Zr-, and Hf-based MOFs, are one of the most attractive classes of MOF materials owing to their superior chemical stability and structural tunability. Despite being a relatively new field, MIV-MOFs have attracted significant research attention in the past few years, leading to exciting advances in syntheses and applications. In this outlook, we start with a brief overview of the history and current status of MIV-MOFs, emphasizing the challenges encountered in their syntheses. The unique properties of MIV-MOFs are discussed, including their high chemical stability and strong tolerance toward defects. Particular emphasis is placed on defect engineering in Zr-MOFs which offers additional routes to tailor their functions. Photocatalysis of MIV-MOF is introduced as a representative example of their emerging applications. Finally, we conclude with the perspective of new opportunities in synthesis and defect engineering. PMID:29721526

  16. Combustion By-Products and their Health Effects--combustion engineering and global health in the 21st century: issues and challenges.

    PubMed

    Lomnicki, Slawo; Gullett, Brian; Stöger, Tobias; Kennedy, Ian; Diaz, Jim; Dugas, Tammy R; Varner, Kurt; Carlin, Danielle J; Dellinger, Barry; Cormier, Stephania A

    2014-01-01

    The 13th International Congress on Combustion By-Products and their Health Effects was held in New Orleans, Louisiana from May 15 to 18, 2013. The congress, sponsored by the Superfund Research Program, National Institute of Environmental Health Sciences, and National Science Foundation, brought together international academic and government researchers, engineers, scientists, and policymakers. With industrial growth, increased power needs and generation and coal consumption and their concomitant emissions, pernicious health effects associated with exposures to these emissions are on the rise. This congress provides a unique platform for interdisciplinary exchange and discussion of these topics. The formation, conversion, control, and health effects of combustion by-products, including particulate matter and associated heavy metals, persistent organic pollutants, and environmentally persistent free radicals, were discussed during the congress. This review will summarize and discuss the implications of the data presented.

  17. Electrodeposited MCrAlY Coatings for Gas Turbine Engine Applications

    NASA Astrophysics Data System (ADS)

    Zhang, Y.

    2015-11-01

    Electrolytic codeposition is a promising alternative process for fabricating MCrAlY coatings. The coating process involves two steps, i.e., codeposition of CrAlY-based particles and a metal matrix of Ni, Co, or (Ni,Co), followed by a diffusion heat treatment to convert the composite coating to the desired MCrAlY microstructure. Despite the advantages such as low cost and non-line-of-sight, this coating process is less known than electron beam-physical vapor deposition and thermal spray processes for manufacturing high-temperature coatings. This article provides an overview of the electro-codeposited MCrAlY coatings for gas turbine engine applications, highlighting the unique features of this coating process and some important findings in the past 30 years. Challenges and research opportunities for further optimization of this type of MCrAlY coatings are also discussed.

  18. Anomalous Stretchable Conductivity Using an Engineered Tricot Weave.

    PubMed

    Lee, Yong-Hee; Kim, Yoonseob; Lee, Tae-Ik; Lee, Inhwa; Shin, Jaeho; Lee, Hyun Soo; Kim, Taek-Soo; Choi, Jang Wook

    2015-12-22

    Robust electric conduction under stretching motions is a key element in upcoming wearable electronic devices but is fundamentally very difficult to achieve because percolation pathways in conductive media are subject to collapse upon stretching. Here, we report that this fundamental challenge can be overcome by using a parameter uniquely available in textiles, namely a weaving structure. A textile structure alternately interwoven with inelastic and elastic yarns, achieved via a tricot weave, possesses excellent elasticity (strain up to 200%) in diagonal directions. When this textile is coated with conductive nanomaterials, proper textile engineering allows the textile to obtain an unprecedented 7-fold conductivity increase, with conductivity reaching 33,000 S cm(-1), even at 130% strain, due to enhanced interyarn contacts. The observed stretching conductivity can be described well using a modified 3D percolation theory that reflects the weaving effect and is also utilized for stretchable electronic interconnects and supercapacitors with high performance.

  19. Combustion By-Products and their Health Effects - Combustion Engineering and Global Health in the 21st Century: Issues and Challenges

    PubMed Central

    Lomnicki, Slawo; Gullett, Brian; Stöger, Tobias; Kennedy, Ian; Diaz, Jim; Dugas, Tammy R.; Varner, Kurt; Carlin, Danielle; Dellinger, Barry; Cormier, Stephania A.

    2014-01-01

    The 13th International Congress on Combustion By-Products and their Health Effects was held in New Orleans, Louisiana from May 15–18, 2013. The congress, sponsored by the Superfund Research Program, National Institute of Environmental Health Sciences, and National Science Foundation, brought together international academic and government researchers, engineers, scientists and policymakers. With industrial growth, increased power needs and generation and coal consumption and their concomitant emissions, pernicious health effects associated with exposures to these emissions are on the rise. This congress provides a unique platform for interdisciplinary exchange and discussion of these topics. The formation, conversion, control and health effects of combustion by-products, including particulate matter and associated heavy metals, persistent organic pollutants and environmentally persistent free radicals, were discussed during the congress. This review will summarize and discuss the implications of the data presented. PMID:24434722

  20. Surface Engineering of Graphene-Based Nanomaterials for Biomedical Applications

    PubMed Central

    2015-01-01

    Graphene-based nanomaterials have attracted tremendous interest over the past decade due to their unique electronic, optical, mechanical, and chemical properties. However, the biomedical applications of these intriguing nanomaterials are still limited due to their suboptimal solubility/biocompatibility, potential toxicity, and difficulties in achieving active tumor targeting, just to name a few. In this Topical Review, we will discuss in detail the important role of surface engineering (i.e., bioconjugation) in improving the in vitro/in vivo stability and enriching the functionality of graphene-based nanomaterials, which can enable single/multimodality imaging (e.g., optical imaging, positron emission tomography, magnetic resonance imaging) and therapy (e.g., photothermal therapy, photodynamic therapy, and drug/gene delivery) of cancer. Current challenges and future research directions are also discussed and we believe that graphene-based nanomaterials are attractive nanoplatforms for a broad array of future biomedical applications. PMID:25117569

  1. Citrate-Based Biomaterials and Their Applications in Regenerative Engineering

    PubMed Central

    Tran, Richard T.; Yang, Jian; Ameer, Guillermo A.

    2015-01-01

    Advances in biomaterials science and engineering are crucial to translating regenerative engineering, an emerging field that aims to recreate complex tissues, into clinical practice. In this regard, citrate-based biomaterials have become an important tool owing to their versatile material and biological characteristics including unique antioxidant, antimicrobial, adhesive, and fluorescent properties. This review discusses fundamental design considerations, strategies to incorporate unique functionality, and examples of how citrate-based biomaterials can be an enabling technology for regenerative engineering. PMID:27004046

  2. The influence of college choice on the success, ethnic identity, and professional sense of belonging of African American engineers

    NASA Astrophysics Data System (ADS)

    DeRamus-Suazo, Nicole L.

    The purpose of this study was to reveal the perceptions of African American engineers on how college choice influenced their success, ethnic identity, and professional sense of belonging by documenting the unique experiences and success stories of African American engineers who attended four-year institutions, historically Black colleges and universities (HBCUs) and predominantly White institutions (PWIs). The research question was best answered through a qualitative, phenomenological study that depicted the lived experiences of individuals in their own voice. The governing interest was in discovering whether aspiring African American engineers, at this stage in their professional experience, favorably viewed their choice of HBCUs versus PWIs. Participants relayed how having a sense of belonging to their institution and having a supportive network of peers and faculty influenced and shaped their outlook on life. Several of the participants spoke of being resolute in achieving their goal to become an engineer despite the challenges faced in college and in the workforce. Whether participants attended an HBCU or PWI, they felt a sense of achievement and a competence to walk into any situation and succeed. Overwhelmingly, most participants expressed they would choose their undergraduate institution again if given the opportunity. African American engineers favorably viewed their undergraduate college choice as having given them an opportunity to achieve their professional aspirations.

  3. Adaptive Systems Engineering: A Medical Paradigm for Practicing Systems Engineering

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

    R. Douglas Hamelin; Ron D. Klingler; Christopher Dieckmann

    2011-06-01

    From its inception in the defense and aerospace industries, SE has applied holistic, interdisciplinary tools and work-process to improve the design and management of 'large, complex engineering projects.' The traditional scope of engineering in general embraces the design, development, production, and operation of physical systems, and SE, as originally conceived, falls within that scope. While this 'traditional' view has expanded over the years to embrace wider, more holistic applications, much of the literature and training currently available is still directed almost entirely at addressing the large, complex, NASA and defense-sized systems wherein the 'ideal' practice of SE provides the cradle-to-gravemore » foundation for system development and deployment. Under such scenarios, systems engineers are viewed as an integral part of the system and project life-cycle from conception to decommissioning. In far less 'ideal' applications, SE principles are equally applicable to a growing number of complex systems and projects that need to be 'rescued' from overwhelming challenges that threaten imminent failure. The medical profession provides a unique analogy for this latter concept and offers a useful paradigm for tailoring our 'practice' of SE to address the unexpected dynamics of applying SE in the real world. In short, we can be much more effective as systems engineers as we change some of the paradigms under which we teach and 'practice' SE.« less

  4. Navigating Transitions: Challenges for Engineering Students

    ERIC Educational Resources Information Center

    Moore-Russo, Deborah; Wilsey, Jillian N.; Parthum, Michael J., Sr.; Lewis, Kemper

    2017-01-01

    As college students enter engineering, they face challenges when they navigate across various transitions. These challenges impact whether a student can successfully adapt to the rigorous curricular requirements of an engineering degree and to the norms and expectations that are particular to engineering. This article focuses on the transitions…

  5. Failure is an option: Reactions to failure in elementary engineering design projects

    NASA Astrophysics Data System (ADS)

    Johnson, Matthew M.

    Recent reform documents in science education have called for teachers to use epistemic practices of science and engineering researchers to teach disciplinary content (NRC, 2007; NRC, 2012; NGSS Lead States, 2013). Although this creates challenges for classroom teachers unfamiliar with engineering, it has created a need for high quality research about how students and teachers engage in engineering activities to improve curriculum development and teaching pedagogy. While framers of the Next Generation Science Standards (NRC, 2012; NGSS Lead States 2013) focused on the similarities of the practices of science researchers and engineering designers, some have proposed that engineering has a unique set of epistemic practices, including improving from failure (Cunningham & Carlsen, 2014; Cunningham & Kelly, in review). While no one will deny failures occur in science, failure in engineering is thought of in fundamentally different ways. In the study presented here, video data from eight classes of elementary students engaged in one of two civil engineering units were analyzed using methods borrowed from psychology, anthropology, and sociolinguistics to investigate: 1) the nature of failure in elementary engineering design; 2) the ways in which teachers react to failure; and 3) how the collective actions of students and teachers support or constrain improvement in engineering design. I propose new ways of considering the types and causes of failure, and note three teacher reactions to failure: the manager, the cheerleader, and the strategic partner. Because the goal of iteration in engineering is improvement, I also studied improvement. Students only systematically improve when they have the opportunity, productive strategies, and fair comparisons between prototypes. I then investigate the use of student engineering journals to assess learning from the process of improvement after failure. After discussion, I consider implications from this work as well as future research to advance our understanding in this area.

  6. Development of Computational Tools for Metabolic Model Curation, Flux Elucidation and Strain Design

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

    Maranas, Costas D

    An overarching goal of the Department of Energy mission is the efficient deployment and engineering of microbial and plant systems to enable biomass conversion in pursuit of high energy density liquid biofuels. This has spurred the pace at which new organisms are sequenced and annotated. This torrent of genomic information has opened the door to understanding metabolism in not just skeletal pathways and a handful of microorganisms but for truly genome-scale reconstructions derived for hundreds of microbes and plants. Understanding and redirecting metabolism is crucial because metabolic fluxes are unique descriptors of cellular physiology that directly assess the current cellularmore » state and quantify the effect of genetic engineering interventions. At the same time, however, trying to keep pace with the rate of genomic data generation has ushered in a number of modeling and computational challenges related to (i) the automated assembly, testing and correction of genome-scale metabolic models, (ii) metabolic flux elucidation using labeled isotopes, and (iii) comprehensive identification of engineering interventions leading to the desired metabolism redirection.« less

  7. Enhancement of electrical signaling in neural networks on graphene films.

    PubMed

    Tang, Mingliang; Song, Qin; Li, Ning; Jiang, Ziyun; Huang, Rong; Cheng, Guosheng

    2013-09-01

    One of the key challenges for neural tissue engineering is to exploit supporting materials with robust functionalities not only to govern cell-specific behaviors, but also to form functional neural network. The unique electrical and mechanical properties of graphene imply it as a promising candidate for neural interfaces, but little is known about the details of neural network formation on graphene as a scaffold material for tissue engineering. Therapeutic regenerative strategies aim to guide and enhance the intrinsic capacity of the neurons to reorganize by promoting plasticity mechanisms in a controllable manner. Here, we investigated the impact of graphene on the formation and performance in the assembly of neural networks in neural stem cell (NSC) culture. Using calcium imaging and electrophysiological recordings, we demonstrate the capabilities of graphene to support the growth of functional neural circuits, and improve neural performance and electrical signaling in the network. These results offer a better understanding of interactions between graphene and NSCs, also they clearly present the great potentials of graphene as neural interface in tissue engineering. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Hyperthermal Environments Simulator for Nuclear Rocket Engine Development

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.; Foote, John P.; Clifton, W. B.; Hickman, Robert R.; Wang, Ten-See; Dobson, Christopher C.

    2011-01-01

    An arc-heater driven hyperthermal convective environments simulator was recently developed and commissioned for long duration hot hydrogen exposure of nuclear thermal rocket materials. This newly established non-nuclear testing capability uses a high-power, multi-gas, wall-stabilized constricted arc-heater to produce hightemperature pressurized hydrogen flows representative of nuclear reactor core environments, excepting radiation effects, and is intended to serve as a low-cost facility for supporting non-nuclear developmental testing of hightemperature fissile fuels and structural materials. The resulting reactor environments simulator represents a valuable addition to the available inventory of non-nuclear test facilities and is uniquely capable of investigating and characterizing candidate fuel/structural materials, improving associated processing/fabrication techniques, and simulating reactor thermal hydraulics. This paper summarizes facility design and engineering development efforts and reports baseline operational characteristics as determined from a series of performance mapping and long duration capability demonstration tests. Potential follow-on developmental strategies are also suggested in view of the technical and policy challenges ahead. Keywords: Nuclear Rocket Engine, Reactor Environments, Non-Nuclear Testing, Fissile Fuel Development.

  9. COMPARATIVE IN VITRO PULMONARY TOXICITY OF ENGINEERED, MANUFACTURED, AND ENVIRONMENTAL NANOPARTICLES

    EPA Science Inventory

    Engineered nanomaterials display many unique physicochemical properties for a variety of applications and due to their novel propertiesapplications may have unique routes of exposure and toxicity. This study examines the: 1) ability of the MTT assay to generate false positives or...

  10. The space shuttle ascent vehicle aerodynamic challenges configuration design and data base development

    NASA Technical Reports Server (NTRS)

    Dill, C. C.; Young, J. C.; Roberts, B. B.; Craig, M. K.; Hamilton, J. T.; Boyle, W. W.

    1985-01-01

    The phase B Space Shuttle systems definition studies resulted in a generic configuration consisting of a delta wing orbiter, and two solid rocket boosters (SRB) attached to an external fuel tank (ET). The initial challenge facing the aerodynamic community was aerodynamically optimizing, within limits, this configuration. As the Shuttle program developed and the sensitivities of the vehicle to aerodynamics were better understood the requirements of the aerodynamic data base grew. Adequately characterizing the vehicle to support the various design studies exploded the size of the data base to proportions that created a data modeling/management challenge for the aerodynamicist. The ascent aerodynamic data base originated primarily from wind tunnel test results. The complexity of the configuration rendered conventional analytic methods of little use. Initial wind tunnel tests provided results which included undesirable effects from model support tructure, inadequate element proximity, and inadequate plume simulation. The challenge to improve the quality of test results by determining the extent of these undesirable effects and subsequently develop testing techniques to eliminate them was imposed on the aerodynamic community. The challenges to the ascent aerodynamics community documented are unique due to the aerodynamic complexity of the Shuttle launch. Never before was such a complex vehicle aerodynamically characterized. The challenges were met with innovative engineering analyses/methodology development and wind tunnel testing techniques.

  11. Dental implants modified with drug releasing titania nanotubes: therapeutic potential and developmental challenges.

    PubMed

    Gulati, Karan; Ivanovski, Sašo

    2017-08-01

    The transmucosal nature of dental implants presents a unique therapeutic challenge, requiring not only rapid establishment and subsequent maintenance of osseointegration, but also the formation of resilient soft tissue integration. Key challenges in achieving long-term success are sub-optimal bone integration in compromised bone conditions and impaired trans-mucosal tissue integration in the presence of a persistent oral microbial biofilm. These challenges can be targeted by employing a drug-releasing implant modification such as TiO 2 nanotubes (TNTs), engineered on titanium surfaces via electrochemical anodization. Areas covered: This review focuses on applications of TNT-based dental implants towards achieving optimal therapeutic efficacy. Firstly, the functions of TNT implants will be explored in terms of their influence on osseointegration, soft tissue integration and immunomodulation. Secondly, the developmental challenges associated with such implants are reviewed including sterilization, stability and toxicity. Expert opinion: The potential of TNTs is yet to be fully explored in the context of the complex oral environment, including appropriate modulation of alveolar bone healing, immune-inflammatory processes, and soft tissue responses. Besides long-term in vivo assessment under masticatory loading conditions, investigating drug-release profiles in vivo and addressing various technical challenges are required to bridge the gap between research and clinical dentistry.

  12. FY10 Engineering Innovations, Research and Technology Report

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

    Lane, M A; Aceves, S M; Paulson, C N

    This report summarizes key research, development, and technology advancements in Lawrence Livermore National Laboratory's Engineering Directorate for FY2010. These efforts exemplify Engineering's nearly 60-year history of developing and applying the technology innovations needed for the Laboratory's national security missions, and embody Engineering's mission to ''Enable program success today and ensure the Laboratory's vitality tomorrow.'' Leading off the report is a section featuring compelling engineering innovations. These innovations range from advanced hydrogen storage that enables clean vehicles, to new nuclear material detection technologies, to a landmine detection system using ultra-wideband ground-penetrating radar. Many have been recognized with R&D Magazine's prestigious R&Dmore » 100 Award; all are examples of the forward-looking application of innovative engineering to pressing national problems and challenging customer requirements. Engineering's capability development strategy includes both fundamental research and technology development. Engineering research creates the competencies of the future where discovery-class groundwork is required. Our technology development (or reduction to practice) efforts enable many of the research breakthroughs across the Laboratory to translate from the world of basic research to the national security missions of the Laboratory. This portfolio approach produces new and advanced technological capabilities, and is a unique component of the value proposition of the Lawrence Livermore Laboratory. The balance of the report highlights this work in research and technology, organized into thematic technical areas: Computational Engineering; Micro/Nano-Devices and Structures; Measurement Technologies; Engineering Systems for Knowledge Discovery; and Energy Manipulation. Our investments in these areas serve not only known programmatic requirements of today and tomorrow, but also anticipate the breakthrough engineering innovations that will be needed in the future.« less

  13. Structural and mechanical design challenges of space shuttle solid rocket boosters separation and recovery subsystems

    NASA Technical Reports Server (NTRS)

    Woodis, W. R.; Runkle, R. E.

    1985-01-01

    The design of the space shuttle solid rocket booster (SRB) subsystems for reuse posed some unique and challenging design considerations. The separation of the SRBs from the cluster (orbiter and external tank) at 150,000 ft when the orbiter engines are running at full thrust meant the two SRBs had to have positive separation forces pushing them away. At the same instant, the large attachments that had reacted launch loads of 7.5 million pounds thrust had to be servered. These design considerations dictated the design requirements for the pyrotechnics and separation rocket motors. The recovery and reuse of the two SRBs meant they had to be safely lowered to the ocean, remain afloat, and be owed back to shore. In general, both the pyrotechnic and recovery subsystems have met or exceeded design requirements. In twelve vehicles, there has only been one instance where the pyrotechnic system has failed to function properly.

  14. Identifying the challenging factors in the transition from colleges of engineering to employment

    NASA Astrophysics Data System (ADS)

    Baytiyeh, Hoda; Naja, Mohamad

    2012-03-01

    The transition from university to a career in engineering is a challenging process. This study examined the perceptions of engineering graduates regarding the difficulties they encountered in their transition from the university to the workplace. Lebanese practising engineers (n=217), living around the world, were surveyed to identify their current employment situations and their attitudes toward their academic preparation. Factor analysis revealed three main challenges facing engineering graduates: communication; responsibility; self-confidence. Seventeen interviews were conducted to gather information on ways to facilitate this transition. Comments reflected the need for better collaboration between engineering schools and engineering firms. The results will provide insight for engineering colleges, faculty members and administrators into the challenges faced by graduates and their aspirations for a smoother transition into employment.

  15. EDITORIAL: The 6th International Workshop on Micro and Nanotechnologies for Power Generation and Energy Conversion Applications (PowerMEMS 2006)

    NASA Astrophysics Data System (ADS)

    Fréchette, Luc G.

    2007-09-01

    Energy is a sector of paramount importance over the coming decades if we are to ensure sustainable development that respects our environment. The research and development of novel approaches to convert available energy into usable forms using micro and nanotechnologies can contribute towards this goal and meet the growing need for power in small scale portable applications. The dominant power sources for handheld and other portable electronics are currently primary and rechargeable batteries. Their limited energy density and adverse effects on the environment upon disposal suggest that alternative approaches need to be explored. This special issue will showcase some of the leading work in this area, initially presented at PowerMEMS 2006, the 6th International Workshop on Micro and Nanotechnologies for Power Generation and Energy Conversion Applications. Power MEMS are defined as microsystems for electrical power generation and other energy conversion applications, including propulsion and cooling. The range of power MEMS technologies includes micro thermodynamic machines, such as microturbines, miniature internal combustion engines and micro-coolers; solid-state direct energy conversion, such as thermoelectric and photovoltaic microstructures; micro electrochemical devices, such as micro fuel cells and nanostructure batteries; vibration energy harvesting devices, such as piezoelectric, magnetic or electrostatic micro generators, as well as micro thrusters and rocket engines for propulsion. These can either be driven by scavenging thermal, mechanical or solar energy from the environment, or from a stored energy source, such as chemical fuel or radioactive material. The unique scope leads to unique challenges in the development of power MEMS, ranging from the integration of novel materials to the efficient small scale implementation of energy conversion principles. In this special issue, Mitcheson et al provide a comparative assessment of three inertial vibration energy harvesting approaches. Technologies and approaches for micro heat engines are shared, ranging from a complete microsystem for thermal energy harvesting (Cho et al) to core bearing and microturbomachinery technologies for rotating micro heat engines (Waits et al, Nakajima et al). Electrochemical microsystems are also presented, based on methanol as fuel (Morse et al), as well as novel micro and nanofabrication approaches (Chu et al). Fuel cell microsystems with integrated hydrogen generation approaches are also investigated by Peterson et al and Varady et al, illustrating the benefits and challenges of miniaturizing complete power sources. Finally, biological micro fuel cells that leverage the principles found in nature are presented, in contrast to chemical fuel cells (Chen et al, Morishima et al). We hope that this work will inspire others to pursue innovative research and development activities in the area of power MEMS, and consequently contribute to addressing our energy challenges for the 21st century.

  16. Using the SWAT model to improve process descriptions and define hydrologic partitioning in South Korea

    NASA Astrophysics Data System (ADS)

    Shope, C. L.; Maharjan, G. R.; Tenhunen, J.; Seo, B.; Kim, K.; Riley, J.; Arnhold, S.; Koellner, T.; Ok, Y. S.; Peiffer, S.; Kim, B.; Park, J.-H.; Huwe, B.

    2014-02-01

    Watershed-scale modeling can be a valuable tool to aid in quantification of water quality and yield; however, several challenges remain. In many watersheds, it is difficult to adequately quantify hydrologic partitioning. Data scarcity is prevalent, accuracy of spatially distributed meteorology is difficult to quantify, forest encroachment and land use issues are common, and surface water and groundwater abstractions substantially modify watershed-based processes. Our objective is to assess the capability of the Soil and Water Assessment Tool (SWAT) model to capture event-based and long-term monsoonal rainfall-runoff processes in complex mountainous terrain. To accomplish this, we developed a unique quality-control, gap-filling algorithm for interpolation of high-frequency meteorological data. We used a novel multi-location, multi-optimization calibration technique to improve estimations of catchment-wide hydrologic partitioning. The interdisciplinary model was calibrated to a unique combination of statistical, hydrologic, and plant growth metrics. Our results indicate scale-dependent sensitivity of hydrologic partitioning and substantial influence of engineered features. The addition of hydrologic and plant growth objective functions identified the importance of culverts in catchment-wide flow distribution. While this study shows the challenges of applying the SWAT model to complex terrain and extreme environments; by incorporating anthropogenic features into modeling scenarios, we can enhance our understanding of the hydroecological impact.

  17. Space Shuttle Main Engine Joint Data List Applying Today's Desktop Technologies to Facilitate Engine Processing

    NASA Technical Reports Server (NTRS)

    Jacobs, Kenneth; Drobnick, John; Krell, Don; Neuhart, Terry; McCool, A. (Technical Monitor)

    2001-01-01

    Boeing-Rocketdyne's Space Shuttle Main Engine (SSME) is the world's first large reusable liquid rocket engine. The space shuttle propulsion system has three SSMEs, each weighing 7,400 lbs and providing 470,000 lbs of thrust at 100% rated power level. To ensure required safety and reliability levels are achieved with the reusable engines, each SSME is partially disassembled, inspected, reassembled, and retested at Kennedy Space Center between each flight. Maintenance processing must be performed very carefully to replace any suspect components, maintain proper engine configuration, and avoid introduction of contaminants that could affect performance and safety. The long service life, and number, complexity, and pedigree of SSME components makes logistics functions extremely critical. One SSME logistics challenge is documenting the assembly and disassembly of the complex joint configurations. This data (joint nomenclature, seal and fastener identification and orientation, assembly sequence, fastener torques, etc.) must be available to technicians and engineers during processing. Various assembly drawings and procedures contain this information, but in this format the required (practical) joint data can be hard to find, due to the continued use of archaic engineering drawings and microfilm for field site use. Additionally, the release system must traverse 2,500 miles between design center and field site, across three time zones, which adds communication challenges and time lags for critical engine configuration data. To aid in information accessibility, a Joint Data List (JDL) was developed that allows efficient access to practical joint data. The published JDL has been a very useful logistics product, providing illustrations and information on the latest SSME configuration. The JDL identifies over 3,350 unique parts across seven fluid systems, over 300 joints, times two distinct engine configurations. The JDL system was recently converted to a web-based, navigable electronic manual that contains all the required data and illustrations in expanded view format using standard PC products (Word, Excel, PDF, Photoshop). The logistics of accurately releasing this information to field personnel was greatly enhanced via the utilization of common office products to produce a more user-friendly format than was originally developed under contract to NASA. This was done without reinventing the system, which would be cost prohibitive on a program of this maturity. The brunt of the joint part tracking is done within the logistics organization and disseminated to all field sites, without duplicating effort at each site. The JDL is easily accessible across the country via the NASA intranet directly at the SSME workstand. The advent of this logistics data product has greatly enhanced the reliability of tracking dynamic changes to the SSME and greatly reduces engineering change turnaround time and potential for errors. Since the inception of the JDL system in 1997, no discrepant parts have propagated to engine assembly operations. This presentation focuses on the challenges overcome and the techniques used to apply today's desktop technologies to an existing logistics data source.

  18. Design Process of Flight Vehicle Structures for a Common Bulkhead and an MPCV Spacecraft Adapter

    NASA Technical Reports Server (NTRS)

    Aggarwal, Pravin; Hull, Patrick V.

    2015-01-01

    Design and manufacturing space flight vehicle structures is a skillset that has grown considerably at NASA during that last several years. Beginning with the Ares program and followed by the Space Launch System (SLS); in-house designs were produced for both the Upper Stage and the SLS Multipurpose crew vehicle (MPCV) spacecraft adapter. Specifically, critical design review (CDR) level analysis and flight production drawing were produced for the above mentioned hardware. In particular, the experience of this in-house design work led to increased manufacturing infrastructure for both Marshal Space Flight Center (MSFC) and Michoud Assembly Facility (MAF), improved skillsets in both analysis and design, and hands on experience in building and testing (MSA) full scale hardware. The hardware design and development processes from initiation to CDR and finally flight; resulted in many challenges and experiences that produced valuable lessons. This paper builds on these experiences of NASA in recent years on designing and fabricating flight hardware and examines the design/development processes used, as well as the challenges and lessons learned, i.e. from the initial design, loads estimation and mass constraints to structural optimization/affordability to release of production drawing to hardware manufacturing. While there are many documented design processes which a design engineer can follow, these unique experiences can offer insight into designing hardware in current program environments and present solutions to many of the challenges experienced by the engineering team.

  19. The Roles of Engineering Notebooks in Shaping Elementary Engineering Student Discourse and Practice

    ERIC Educational Resources Information Center

    Hertel, Jonathan D.; Cunningham, Christine M.; Kelly, Gregory J.

    2017-01-01

    Engineering design challenges offer important opportunities for students to learn science and engineering knowledge and practices. This study examines how students' engineering notebooks across four units of the curriculum "Engineering is Elementary" (EiE) support student work during design challenges. Through educational ethnography and…

  20. Industrial-strength ecology: trade-offs and opportunities in algal biofuel production.

    PubMed

    Shurin, Jonathan B; Abbott, Rachel L; Deal, Michael S; Kwan, Garfield T; Litchman, Elena; McBride, Robert C; Mandal, Shovon; Smith, Val H

    2013-11-01

    Microalgae represent one of the most promising groups of candidate organisms for replacing fossil fuels with contemporary primary production as a renewable source of energy. Algae can produce many times more biomass per unit area than terrestrial crop plants, easing the competing demands for land with food crops and native ecosystems. However, several aspects of algal biology present unique challenges to the industrial-scale aquaculture of photosynthetic microorganisms. These include high susceptibility to invading aquatic consumers and weeds, as well as prodigious requirements for nutrients that may compete with the fertiliser demands of other crops. Most research on algal biofuel technologies approaches these problems from a cellular or genetic perspective, attempting either to engineer or select algal strains with particular traits. However, inherent functional trade-offs may limit the capacity of genetic selection or synthetic biology to simultaneously optimise multiple functional traits for biofuel productivity and resilience. We argue that a community engineering approach that manages microalgal diversity, species composition and environmental conditions may lead to more robust and productive biofuel ecosystems. We review evidence for trade-offs, challenges and opportunities in algal biofuel cultivation with a goal of guiding research towards intensifying bioenergy production using established principles of community and ecosystem ecology. © 2013 John Wiley & Sons Ltd/CNRS.

  1. Designing to Sample the Unknown: Lessons from OSIRIS-REx Project Systems Engineering

    NASA Technical Reports Server (NTRS)

    Everett, David; Mink, Ronald; Linn, Timothy; Wood, Joshua

    2017-01-01

    On September 8, 2016, the third NASA New Frontiers mission launched on an Atlas V 411. The Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) will rendezvous with asteroid Bennu in 2018, collect a sample in 2020, and return that sample to Earth in September 2023. The development team has overcome a number of challenges in order to design and build a system that will make contact with an unexplored, airless, low-gravity body. This paper will provide an overview of the mission, then focus in on the system-level challenges and some of the key system-level processes. Some of the lessons here are unique to the type of mission, like discussion of operating at a largely-unknown, low-gravity object. Other lessons, particularly from the build phase, have broad implications. The OSIRIS-REx risk management process was particularly effective in achieving an on-time and under-budget development effort. The systematic requirements management and verification and the system validation also helped identify numerous potential problems. The final assessment of the OSIRIS-REx performance will need to wait until the sample is returned in 2023, but this post-launch assessment will capture some of the key systems-engineering lessons from the development team.

  2. Enhanced Bank of Kalman Filters Developed and Demonstrated for In-Flight Aircraft Engine Sensor Fault Diagnostics

    NASA Technical Reports Server (NTRS)

    Kobayashi, Takahisa; Simon, Donald L.

    2005-01-01

    In-flight sensor fault detection and isolation (FDI) is critical to maintaining reliable engine operation during flight. The aircraft engine control system, which computes control commands on the basis of sensor measurements, operates the propulsion systems at the demanded conditions. Any undetected sensor faults, therefore, may cause the control system to drive the engine into an undesirable operating condition. It is critical to detect and isolate failed sensors as soon as possible so that such scenarios can be avoided. A challenging issue in developing reliable sensor FDI systems is to make them robust to changes in engine operating characteristics due to degradation with usage and other faults that can occur during flight. A sensor FDI system that cannot appropriately account for such scenarios may result in false alarms, missed detections, or misclassifications when such faults do occur. To address this issue, an enhanced bank of Kalman filters was developed, and its performance and robustness were demonstrated in a simulation environment. The bank of filters is composed of m + 1 Kalman filters, where m is the number of sensors being used by the control system and, thus, in need of monitoring. Each Kalman filter is designed on the basis of a unique fault hypothesis so that it will be able to maintain its performance if a particular fault scenario, hypothesized by that particular filter, takes place.

  3. Design Analysis of a High Temperature Radiator for the Variable Specific Impulse Magnetoplasma Rocket (VASIMR)

    NASA Technical Reports Server (NTRS)

    Sheth, Rubik B.; Ungar, Eugene K.; Chambliss, Joe P.; Cassady, Leonard D.

    2011-01-01

    The Variable Specific Impulse Magnetoplasma Rocket (VASIMR), currently under development by Ad Astra Rocket Company, is a unique propulsion system that can potentially change the way space propulsion is performed. VASIMR's efficiency, when compared to that of a conventional chemical rocket, reduce propellant needed for exploration missions by a factor of 10. Currently plans include flight tests of a 200 kW VASIMR system, titled VF-200, on the International Space Station. The VF-200 will consist of two 100 kW thruster units packaged together in one engine bus. Each thruster unit has a unique heat rejection requirement of about 27 kW over a firing time of 15 minutes. In order to control rocket core temperatures, peak operating temperatures of about 300 C are expected within the thermal control loop. Design of a high temperature radiator is a unique challenge for the vehicle design. This paper will discuss the path taken to develop a steady state and transient based radiator design. The paper will describe radiator design options for the VASIMR thermal control system for use on ISS as well as future exploration vehicles.

  4. Turning carbon dioxide into fuel.

    PubMed

    Jiang, Z; Xiao, T; Kuznetsov, V L; Edwards, P P

    2010-07-28

    Our present dependence on fossil fuels means that, as our demand for energy inevitably increases, so do emissions of greenhouse gases, most notably carbon dioxide (CO2). To avoid the obvious consequences on climate change, the concentration of such greenhouse gases in the atmosphere must be stabilized. But, as populations grow and economies develop, future demands now ensure that energy will be one of the defining issues of this century. This unique set of (coupled) challenges also means that science and engineering have a unique opportunity-and a burgeoning challenge-to apply their understanding to provide sustainable energy solutions. Integrated carbon capture and subsequent sequestration is generally advanced as the most promising option to tackle greenhouse gases in the short to medium term. Here, we provide a brief overview of an alternative mid- to long-term option, namely, the capture and conversion of CO2, to produce sustainable, synthetic hydrocarbon or carbonaceous fuels, most notably for transportation purposes. Basically, the approach centres on the concept of the large-scale re-use of CO2 released by human activity to produce synthetic fuels, and how this challenging approach could assume an important role in tackling the issue of global CO2 emissions. We highlight three possible strategies involving CO2 conversion by physico-chemical approaches: sustainable (or renewable) synthetic methanol, syngas production derived from flue gases from coal-, gas- or oil-fired electric power stations, and photochemical production of synthetic fuels. The use of CO2 to synthesize commodity chemicals is covered elsewhere (Arakawa et al. 2001 Chem. Rev. 101, 953-996); this review is focused on the possibilities for the conversion of CO2 to fuels. Although these three prototypical areas differ in their ultimate applications, the underpinning thermodynamic considerations centre on the conversion-and hence the utilization-of CO2. Here, we hope to illustrate that advances in the science and engineering of materials are critical for these new energy technologies, and specific examples are given for all three examples. With sufficient advances, and institutional and political support, such scientific and technological innovations could help to regulate/stabilize the CO2 levels in the atmosphere and thereby extend the use of fossil-fuel-derived feedstocks.

  5. Energy and Greenhouse Gas Emission Reduction Opportunities for Civil Works Projects Unique to the US Army Corps of Engineers

    DTIC Science & Technology

    2012-10-26

    3600 hp diesel engine .................................................................................. 24 20 Diesel engine turbocharger ...ERDC/CERL TR-12-19 24 Figure 19. Fairbanks Morse 3600 hp diesel engine. Figure 20. Diesel engine turbocharger . Table 7. Energy consuming

  6. Offshore Wind Energy Systems Engineering Curriculum Development

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

    McGowan, Jon G.; Manwell, James F.; Lackner, Matthew A.

    2012-12-31

    Utility-scale electricity produced from offshore wind farms has the potential to contribute significantly to the energy production of the United States. In order for the U.S. to rapidly develop these abundant resources, knowledgeable scientists and engineers with sound understanding of offshore wind energy systems are critical. This report summarizes the development of an upper-level engineering course in "Offshore Wind Energy Systems Engineering." This course is designed to provide students with a comprehensive knowledge of both the technical challenges of offshore wind energy and the practical regulatory, permitting, and planning aspects of developing offshore wind farms in the U.S. This coursemore » was offered on a pilot basis in 2011 at the University of Massachusetts and the National Renewable Energy Laboratory (NREL), TU Delft, and GL Garrad Hassan have reviewed its content. As summarized in this report, the course consists of 17 separate topic areas emphasizing appropriate engineering fundamentals as well as development, planning, and regulatory issues. In addition to the course summary, the report gives the details of a public Internet site where references and related course material can be obtained. This course will fill a pressing need for the education and training of the U.S. workforce in this critically important area. Fundamentally, this course will be unique due to two attributes: an emphasis on the engineering and technical aspects of offshore wind energy systems, and a focus on offshore wind energy issues specific to the United States.« less

  7. Improving the clinical impact of biomaterials in cancer immunotherapy

    PubMed Central

    Gammon, Joshua M.; Dold, Neil M.; Jewell, Christopher M.

    2016-01-01

    Immunotherapies for cancer have progressed enormously over the past few decades, and hold great promise for the future. The successes of these therapies, with some patients showing durable and complete remission, demonstrate the power of harnessing the immune system to eradicate tumors. However, the effectiveness of current immunotherapies is limited by hurdles ranging from immunosuppressive strategies employed by tumors, to inadequate specificity of existing therapies, to heterogeneity of disease. Further, the vast majority of approved immunotherapies employ systemic delivery of immunomodulators or cells that make addressing some of these challenges more difficult. Natural and synthetic biomaterials–such as biocompatible polymers, self-assembled lipid particles, and implantable biodegradable devices–offer unique potential to address these hurdles by harnessing the benefits of therapeutic targeting, tissue engineering, co-delivery, controlled release, and sensing. However, despite the enormous investment in new materials and nanotechnology, translation of these ideas to the clinic is still an uncommon outcome. Here we review the major challenges facing immunotherapies and discuss how the newest biomaterials and nanotechnologies could help overcome these challenges to create new clinical options for patients. PMID:26871948

  8. Magnetic Resonance Microscopy of the Lung

    NASA Astrophysics Data System (ADS)

    Johnson, G. Allan

    1999-11-01

    The lung presents both challenges and opportunities for study by magnetic resonance imaging (MRI). The technical challenges arise from respiratory and cardiac motion, limited signal from the tissues, and unique physical structure of the lung. These challenges are heightened in magnetic resonance microscopy (MRM) where the spatial resolution may be up to a million times higher than that of conventional MRI. The development of successful techniques for MRM of the lung present enormous opportunities for basic studies of lung structure and function, toxicology, environmental stress, and drug discovery by permitting investigators to study this most essential organ nondestructively in the live animal. Over the last 15 years, scientists at the Duke Center for In Vivo Microscopy have developed techniques for MRM in the live animal through an interdisciplinary program of biology, physics, chemistry, electrical engineering, and computer science. This talk will focus on the development of specialized radiofrequency coils for lung imaging, projection encoding methods to limit susceptibility losses, specialized support structures to control and monitor physiologic motion, and the most recent development of hyperpolarized gas imaging with ^3He and ^129Xe.

  9. Multifunctional Cellular Materials Based on 2D Nanomaterials: Prospects and Challenges.

    PubMed

    Qiu, Ling; He, Zijun; Li, Dan

    2018-01-01

    Recent advances in emerging 2D nanomaterial-based cellular materials (2D-CMs) open up new opportunities for the development of next generation cellular solids with exceptional properties. Herein, an overview of the current research status of 2D-CMs is provided and their future opportunities are highlighted. First, the unique features of 2D nanomaterials are introduced to illustrate why these nanoscale building blocks are promising for the development of novel cellular materials and what the new features of 2D nanoscale building blocks can offer when compared to their 0D and 1D counterparts. An in-depth discussion on the structure-property relationships of 2D-CMs is then provided, and the remarkable functions that can be achieved by engineering their cellular architecture are highlighted. Additionally, the use of 2D-CMs to tackle key challenges in different practical applications is demonstrated. In conclusion, a personal perspective on the challenges and future research directions of 2D-CMs is given. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Enhancing electric-field control of ferromagnetism through nanoscale engineering of high-Tc MnxGe1-x nanomesh.

    PubMed

    Nie, Tianxiao; Tang, Jianshi; Kou, Xufeng; Gen, Yin; Lee, Shengwei; Zhu, Xiaodan; He, Qinglin; Chang, Li-Te; Murata, Koichi; Fan, Yabin; Wang, Kang L

    2016-10-20

    Voltage control of magnetism in ferromagnetic semiconductor has emerged as an appealing solution to significantly reduce the power dissipation and variability beyond current CMOS technology. However, it has been proven to be very challenging to achieve a candidate with high Curie temperature (T c ), controllable ferromagnetism and easy integration with current Si technology. Here we report the effective electric-field control of both ferromagnetism and magnetoresistance in unique Mn x Ge 1-x nanomeshes fabricated by nanosphere lithography, in which a T c above 400 K is demonstrated as a result of size/quantum confinement. Furthermore, by adjusting Mn doping concentration, extremely giant magnetoresistance is realized from ∼8,000% at 30 K to 75% at 300 K at 4 T, which arises from a geometrically enhanced magnetoresistance effect of the unique mesh structure. Our results may provide a paradigm for fundamentally understanding the high T c in ferromagnetic semiconductor nanostructure and realizing electric-field control of magnetoresistance for future spintronic applications.

  11. Towards efficient bioethanol production from agricultural and forestry residues: Exploration of unique natural microorganisms in combination with advanced strain engineering.

    PubMed

    Zhao, Xinqing; Xiong, Liang; Zhang, Mingming; Bai, Fengwu

    2016-09-01

    Production of fuel ethanol from lignocellulosic feedstocks such as agricultural and forestry residues is receiving increasing attention due to the unsustainable supply of fossil fuels. Three key challenges include high cellulase production cost, toxicity of the cellulosic hydrolysate to microbial strains, and poor ability of fermenting microorganisms to utilize certain fermentable sugars in the hydrolysate. In this article, studies on searching of natural microbial strains for production of unique cellulase for biorefinery of agricultural and forestry wastes, as well as development of strains for improved cellulase production were reviewed. In addition, progress in the construction of yeast strains with improved stress tolerance and the capability to fully utilize xylose and glucose in the cellulosic hydrolysate was also summarized. With the superior microbial strains for high titer cellulase production and efficient utilization of all fermentable sugars in the hydrolysate, economic biofuels production from agricultural residues and forestry wastes can be realized. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Enhancing electric-field control of ferromagnetism through nanoscale engineering of high-Tc MnxGe1−x nanomesh

    PubMed Central

    Nie, Tianxiao; Tang, Jianshi; Kou, Xufeng; Gen, Yin; Lee, Shengwei; Zhu, Xiaodan; He, Qinglin; Chang, Li-Te; Murata, Koichi; Fan, Yabin; Wang, Kang L.

    2016-01-01

    Voltage control of magnetism in ferromagnetic semiconductor has emerged as an appealing solution to significantly reduce the power dissipation and variability beyond current CMOS technology. However, it has been proven to be very challenging to achieve a candidate with high Curie temperature (Tc), controllable ferromagnetism and easy integration with current Si technology. Here we report the effective electric-field control of both ferromagnetism and magnetoresistance in unique MnxGe1−x nanomeshes fabricated by nanosphere lithography, in which a Tc above 400 K is demonstrated as a result of size/quantum confinement. Furthermore, by adjusting Mn doping concentration, extremely giant magnetoresistance is realized from ∼8,000% at 30 K to 75% at 300 K at 4 T, which arises from a geometrically enhanced magnetoresistance effect of the unique mesh structure. Our results may provide a paradigm for fundamentally understanding the high Tc in ferromagnetic semiconductor nanostructure and realizing electric-field control of magnetoresistance for future spintronic applications. PMID:27762320

  13. Silk-microfluidics for advanced biotechnological applications: A progressive review.

    PubMed

    Konwarh, Rocktotpal; Gupta, Prerak; Mandal, Biman B

    2016-01-01

    Silk based biomaterials have not only carved a unique niche in the domain of regenerative medicine but new avenues are also being explored for lab-on-a-chip applications. It is pertinent to note that biospinning of silk represents nature's signature microfluidic-maneuver. Elucidation of non-Newtonian flow of silk in the glands of spiders and silkworms has inspired researchers to fabricate devices for continuous extrusion and concentration of silk. Microfluidic channel networks within porous silk scaffolds ensure optimal nutrient and oxygen supply apart from serving as precursors for vascularization in tissue engineering applications. On the other hand, unique topographical features and surface wettability of natural silk fibers have inspired development of a number of simple and cost-effective devices for applications like blood typing and chemical sensing. This review mirrors the recent progress and challenges in the domain of silk-microfluidics for prospective avant-garde applications in the realm of biotechnology. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. The Need and Challenges for Distributed Engine Control

    NASA Technical Reports Server (NTRS)

    Culley, Dennis E.

    2013-01-01

    The presentation describes the challenges facing the turbine engine control system. These challenges are primarily driven by a dependence on commercial electronics and an increasingly severe environment on board the turbine engine. The need for distributed control is driven by the need to overcome these system constraints and develop a new growth path for control technology and, as a result, improved turbine engine performance.

  15. Variable cycle engines for advanced supersonic transports

    NASA Technical Reports Server (NTRS)

    Howlett, R. A.; Kozlowski, H.

    1975-01-01

    Variable Cycle Engines being studied for advanced commercial supersonic transports show potential for significant environmental and economic improvements relative to 1st generation SST engines. The two most promising concepts are: a Variable Stream Control Engine and a Variable Cycle Engine with a rear flow-control valve. Each concept utilizes variable components and separate burners to provide independent temperature and velocity control for two coannular flow streams. Unique fuel control techniques are combined with cycle characteristics that provide low fuel consumption, similar to a turbojet engine, for supersonic operation. This is accomplished while retaining the good subsonic performance features of a turbofan engine. A two-stream coannular nozzle shows potential to reduce jet noise to below FAR Part 36 without suppressors. Advanced burner concepts have the potential for significant reductions in exhaust emissions. In total, these unique engine concepts have the potential for significant overall improvements to the environmental and economic characteristics of advanced supersonic transports.

  16. Engineering Background: Modern Formats and Challenges of Conceptual Engineering

    NASA Astrophysics Data System (ADS)

    Khamidullina, A. F.; Kuzmina, M. A.; Khusnutdinova, E. M.; Konakhina, I. A.

    2017-09-01

    This paper describes the analysis of problems and development perspectives of engineering education in our and other countries. Special attention is given to modern formats of education that motivate creative efforts of engineers-to-be as well as issues of conceptual engineering taking the challenges of modernity into account.

  17. Protein Network Signatures Associated with Exogenous Biofuels Treatments in Cyanobacterium Synechocystis sp. PCC 6803

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

    Pei, Guangsheng; Chen, Lei; Wang, Jiangxin

    2014-11-03

    Although recognized as a promising microbial cell factory for producing biofuels, current productivity in cyanobacterial systems is low. To make the processes economically feasible, one of the hurdles, which need to be overcome is the low tolerance of hosts to toxic biofuels. Meanwhile, little information is available regarding the cellular responses to biofuels stress in cyanobacteria, which makes it challenging for tolerance engineering. Using large proteomic datasets of Synechocystis under various biofuels stress and environmental perturbation, a protein co-expression network was first constructed and then combined with the experimentally determined protein–protein interaction network. Proteins with statistically higher topological overlap inmore » the integrated network were identified as common responsive proteins to both biofuels stress and environmental perturbations. In addition, a weighted gene co-expression network analysis was performed to distinguish unique responses to biofuels from those to environmental perturbations and to uncover metabolic modules and proteins uniquely associated with biofuels stress. The results showed that biofuel-specific proteins and modules were enriched in several functional categories, including photosynthesis, carbon fixation, and amino acid metabolism, which may represent potential key signatures for biofuels stress responses in Synechocystis. Network-based analysis allowed determination of the responses specifically related to biofuels stress, and the results constituted an important knowledge foundation for tolerance engineering against biofuels in Synechocystis.« less

  18. The DOE fellows program-a workforce development initiative for the US department of energy

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

    Lagos, Leonel E.

    The US Department of Energy Office of Environmental Management (DOE-EM) oversees one of the largest and most technically challenging cleanup programs in the world. The mission of DOE-EM is to complete the safe cleanup of the environmental legacy from five decades of nuclear weapons development and government-sponsored nuclear energy research. Since 1995, Florida International University's Applied Research Center (FIU-ARC) has supported the DOE-EM mission and provided unique research capabilities to address some of these highly technical and difficult challenges. This partnership has allowed FIU-ARC to create a unique infrastructure that is critical for the training and mentoring of science, technology,more » engineering, and math (STEM) students and has exposed many STEM students to 'hands-on' DOE-EM applied research, supervised by the scientists and engineers at ARC. As a result of this successful partnership between DOE and FIU, DOE requested FIU-ARC to create the DOE-FIU Science and Technology Workforce Development Initiative in 2007. This innovative program was established to create a 'pipeline' of minority STEM students trained and mentored to enter DOE's environmental cleanup workforce. The program was designed to help address DOE's future workforce needs by partnering with academic, government and private companies (DOE contractors) to mentor future minority scientists and engineers in the research, development, and deployment of new technologies and processes addressing DOE's environmental cleanup challenges. Since its inception in 2007, the program has trained and mentored 78 FIU STEM minority students. Although, the program has been in existence for only six years, a total of 75 internships have been conducted at DOE National Laboratories, DOE sites, DOE Headquarters and field offices, and DOE contractors. Over 100 DOE Fellows have participated in the Waste Management (WM) Symposia since 2008 with a total of 84 student posters and 7 oral presentations given at WM. The DOE Fellows participation at WM has resulted in three Best Student Poster Awards (WM09, WM10, and WM11) and one Best Professional Poster Award (WM09). DOE Fellows have also presented their research at ANS DD and R and ANS Robotics Topical meetings and this year two Fellows will present at the International Conference on Environmental Remediation and Radioactive Waste Management (ICEM13) in Brussels, Belgium. Moreover, several of our DOE Fellows have already obtained employment with DOE-EM, other federal agencies, DOE contractors, commercial nuclear power companies, and other STEM industry (GE, Boeing, Lockheed Martin, Johnson and Johnson, Beckman-Coulter, and other top companies). This paper will discuss how DOE Fellows program is training and mentoring FIU STEM students in Department of Energy's Office of Environmental Management technical challenges and research. This training and mentoring has resulted in the development of well-trained and polished young scientists and engineers that will become the future workforce in charge of carrying on DOE-EM's environmental cleanup mission. The paper will showcase FIU's DOE Fellows model and highlight some of the applied research the DOE Fellows have conducted at FIU's Applied Research Center and across the DOE Complex by participating in summer internship assignments. (authors)« less

  19. High-Fidelity Simulation in Biomedical and Aerospace Engineering

    NASA Technical Reports Server (NTRS)

    Kwak, Dochan

    2005-01-01

    Contents include the following: Introduction / Background. Modeling and Simulation Challenges in Aerospace Engineering. Modeling and Simulation Challenges in Biomedical Engineering. Digital Astronaut. Project Columbia. Summary and Discussion.

  20. Lunar Prospecting: Searching for Volatiles at the South Pole

    NASA Technical Reports Server (NTRS)

    Trimble, Jay; Carvalho, Robert

    2016-01-01

    The Resource Prospector is an in-situ resource utilization (ISRU) technology demonstration mission, planned for a 2021 launch to search for and analyze volatiles at the Lunar South Pole. The mission poses unique operational challenges. Operating at the Lunar South Pole requires navigating a surface with lighting, shadow and regolith characteristics unlike those of previous missions. The short round trip communications time enables reactive surface operations for science and engineering. Navigation of permanently shadowed regions with a solar powered rover creates risks, including power and thermal management, and requires constant real time decision making for safe entry, path selection and egress. The mission plan requires a faster rover egress from the lander than any previous NASA rover mission.

  1. Risk communication: Uncertainties and the numbers game

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

    Ortigara, M.

    1995-08-30

    The science of risk assessment seeks to characterize the potential risk in situations that may pose hazards to human health or the environment. However, the conclusions reached by the scientists and engineers are not an end in themselves - they are passed on to the involved companies, government agencies, legislators, and the public. All interested parties must then decide what to do with the information. Risk communication is a type of technical communication that involves some unique challenges. This paper first defines the relationships between risk assessment, risk management, and risk communication and then explores two issues in risk communication:more » addressing uncertainty and putting risk number into perspective.« less

  2. U.S. Geological Survey water-resource monitoring activities in support of the Wyoming Landscape Conservation Initiative

    USGS Publications Warehouse

    Soileau, Suzanna; Miller, Kirk

    2013-01-01

    The quality of the Nation’s water resources are vital to the health and well-being of both our communities and the natural landscapes we value. The U.S. Geological Survey investigates the occurrence, quantity, quality, distribution, and movement of surface water and groundwater and provides this information to engineers, scientists, managers, educators, and the general public. This information also supplements current (2013) and historical water data provided by the National Water Information System. The U.S. Geological Survey collects and shares data nationwide, but how those data are used is often site specific; this variety of data assists natural-resource managers in addressing unique, local, and regional challenges.

  3. Auricular reconstruction for microtia: Part II. Surgical techniques.

    PubMed

    Walton, Robert L; Beahm, Elisabeth K

    2002-07-01

    Reconstruction of the microtic ear represents one of the most demanding challenges in reconstructive surgery. In this review the two most commonly used techniques for ear reconstruction, the Brent and Nagata techniques, are addressed in detail. Unique to this endeavor, the originator of each technique has been allowed to submit representative case material and to address the pros and cons of the other's technique. What follows is a detailed, insightful overview of microtia reconstruction, as a state of the art. The review then details commonly encountered problems in ear reconstruction and pertinent technical points. Finally, a glimpse into the future is offered with an accounting of the advances made in tissue engineering as this technology applies to auricular reconstruction.

  4. Wavefront shaping with disorder-engineered metasurfaces

    NASA Astrophysics Data System (ADS)

    Jang, Mooseok; Horie, Yu; Shibukawa, Atsushi; Brake, Joshua; Liu, Yan; Kamali, Seyedeh Mahsa; Arbabi, Amir; Ruan, Haowen; Faraon, Andrei; Yang, Changhuei

    2018-02-01

    Recently, wavefront shaping with disordered media has demonstrated optical manipulation capabilities beyond those of conventional optics, including extended volume, aberration-free focusing and subwavelength focusing. However, translating these capabilities to useful applications has remained challenging as the input-output characteristics of the disordered media (P variables) need to be exhaustively determined via O(P) measurements. Here, we propose a paradigm shift where the disorder is specifically designed so its exact input-output characteristics are known a priori and can be used with only a few alignment steps. We implement this concept with a disorder-engineered metasurface, which exhibits additional unique features for wavefront shaping such as a large optical memory effect range in combination with a wide angular scattering range, excellent stability, and a tailorable angular scattering profile. Using this designed metasurface with wavefront shaping, we demonstrate high numerical aperture (NA > 0.5) focusing and fluorescence imaging with an estimated 2.2 × 108 addressable points in an 8 mm field of view.

  5. Physical Science Informatics: Providing Open Science Access to Microheater Array Boiling Experiment Data

    NASA Technical Reports Server (NTRS)

    McQuillen, John; Green, Robert D.; Henrie, Ben; Miller, Teresa; Chiaramonte, Fran

    2014-01-01

    The Physical Science Informatics (PSI) system is the next step in this an effort to make NASA sponsored flight data available to the scientific and engineering community, along with the general public. The experimental data, from six overall disciplines, Combustion Science, Fluid Physics, Complex Fluids, Fundamental Physics, and Materials Science, will present some unique challenges. Besides data in textual or numerical format, large portions of both the raw and analyzed data for many of these experiments are digital images and video, requiring large data storage requirements. In addition, the accessible data will include experiment design and engineering data (including applicable drawings), any analytical or numerical models, publications, reports, and patents, and any commercial products developed as a result of the research. This objective of paper includes the following: Present the preliminary layout (Figure 2) of MABE data within the PSI database. Obtain feedback on the layout. Present the procedure to obtain access to this database.

  6. Gellan Gum-Based Hydrogels for Osteochondral Repair.

    PubMed

    Costa, Lígia; Silva-Correia, Joana; Oliveira, J Miguel; Reis, Rui L

    2018-01-01

    Gellan gum (GG) is a widely explored natural polysaccharide that has been gaining attention in tissue engineering (TE) and regenerative medicine field, and more recently in osteochondral TE approaches. Taking advantage of its inherent features such as biocompatibility, biodegradability, similarity with the extracellular matrix and easy functionalization, GG-based hydrogels have been studied for their potential for cartilage and bone tissue regeneration. Several preclinical studies describe the successful outcome of GG in cartilage tissue engineering. By its turn, GG composites have also been proposed in several strategies to guide bone formation. The big challenge in osteochondral TE approaches is still to achieve cartilage and bone regeneration simultaneously through a unique integrated bifunctional construct. The potential of GG to be used as polymeric support to reach both bone and cartilage regeneration has been demonstrated. This chapter provides an overview of GG properties and the functionalization strategies employed to tailor its behaviour to a particular application. The use of GG in soft and hard tissues regeneration approaches, as well in osteochondral integrated TE strategies is also revised.

  7. Antarctic subglacial lake exploration: first results and future plans

    PubMed Central

    Siegert, Martin J.; Priscu, John C.; Wadham, Jemma L.; Lyons, W. Berry

    2016-01-01

    After more than a decade of planning, three attempts were made in 2012–2013 to access, measure in situ properties and directly sample subglacial Antarctic lake environments. First, Russian scientists drilled into the top of Lake Vostok, allowing lake water to infiltrate, and freeze within, the lower part of the ice-core borehole, from which further coring would recover a frozen sample of surface lake water. Second, UK engineers tried unsuccessfully to deploy a clean-access hot-water drill, to sample the water column and sediments of subglacial Lake Ellsworth. Third, a US mission successfully drilled cleanly into subglacial Lake Whillans, a shallow hydraulically active lake at the coastal margin of West Antarctica, obtaining samples that would later be used to prove the existence of microbial life and active biogeochemical cycling beneath the ice sheet. This article summarizes the results of these programmes in terms of the scientific results obtained, the operational knowledge gained and the engineering challenges revealed, to collate what is known about Antarctic subglacial environments and how to explore them in future. While results from Lake Whillans testify to subglacial lakes as being viable biological habitats, the engineering challenges to explore deeper more isolated lakes where unique microorganisms and climate records may be found, as exemplified in the Lake Ellsworth and Vostok missions, are considerable. Through international cooperation, and by using equipment and knowledge of the existing subglacial lake exploration programmes, it is possible that such environments could be explored thoroughly, and at numerous sites, in the near future. PMID:26667917

  8. Antarctic subglacial lake exploration: first results and future plans.

    PubMed

    Siegert, Martin J; Priscu, John C; Alekhina, Irina A; Wadham, Jemma L; Lyons, W Berry

    2016-01-28

    After more than a decade of planning, three attempts were made in 2012-2013 to access, measure in situ properties and directly sample subglacial Antarctic lake environments. First, Russian scientists drilled into the top of Lake Vostok, allowing lake water to infiltrate, and freeze within, the lower part of the ice-core borehole, from which further coring would recover a frozen sample of surface lake water. Second, UK engineers tried unsuccessfully to deploy a clean-access hot-water drill, to sample the water column and sediments of subglacial Lake Ellsworth. Third, a US mission successfully drilled cleanly into subglacial Lake Whillans, a shallow hydraulically active lake at the coastal margin of West Antarctica, obtaining samples that would later be used to prove the existence of microbial life and active biogeochemical cycling beneath the ice sheet. This article summarizes the results of these programmes in terms of the scientific results obtained, the operational knowledge gained and the engineering challenges revealed, to collate what is known about Antarctic subglacial environments and how to explore them in future. While results from Lake Whillans testify to subglacial lakes as being viable biological habitats, the engineering challenges to explore deeper more isolated lakes where unique microorganisms and climate records may be found, as exemplified in the Lake Ellsworth and Vostok missions, are considerable. Through international cooperation, and by using equipment and knowledge of the existing subglacial lake exploration programmes, it is possible that such environments could be explored thoroughly, and at numerous sites, in the near future. © 2015 The Author(s).

  9. First-Year Students' Attitudes towards the Grand Challenges and Nanotechnology

    ERIC Educational Resources Information Center

    Lakin, Joni M.; Han, Yi; Davis, Edward

    2016-01-01

    The "Grand Challenges" for Engineering are an effort to portray engineering as a field that has profound impacts on society. This study explores the level of interest first-year engineering students had in various "Grand Challenges" and in nanotechnology topics. We administered a survey to a large sample of students enrolled in…

  10. Academic Preparedness as a Predictor of Achievement in an Engineering Design Challenge

    ERIC Educational Resources Information Center

    Mentzer, Nathan; Becker, Kurt

    2010-01-01

    The purpose of this study was to determine if a student's academic success, measured by grade point average (GPA) in mathematics, science, and communication courses, is correlated with student change in achievement during an engineering design challenge. Engineering design challenges have been implemented and researched in K-16 environments where…

  11. Grand challenges for biological engineering

    PubMed Central

    Yoon, Jeong-Yeol; Riley, Mark R

    2009-01-01

    Biological engineering will play a significant role in solving many of the world's problems in medicine, agriculture, and the environment. Recently the U.S. National Academy of Engineering (NAE) released a document "Grand Challenges in Engineering," covering broad realms of human concern from sustainability, health, vulnerability and the joy of living. Biological engineers, having tools and techniques at the interface between living and non-living entities, will play a prominent role in forging a better future. The 2010 Institute of Biological Engineering (IBE) conference in Cambridge, MA, USA will address, in part, the roles of biological engineering in solving the challenges presented by the NAE. This letter presents a brief outline of how biological engineers are working to solve these large scale and integrated problems of our society. PMID:19772647

  12. Understanding the immunogenicity and antigenicity of nanomaterials: Past, present and future

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

    Ilinskaya, Anna N.; Dobrovolskaia, Marina A., E-ma

    Nanoparticle immunogenicity and antigenicity have been under investigation for many years. During the past decade, significant progress has been made in understanding what makes a nanoparticle immunogenic, how immune cells respond to nanoparticles, what consequences of nanoparticle-specific antibody formation exist and how they challenge the application of nanoparticles for drug delivery. Moreover, it has been recognized that accidental contamination of therapeutic protein formulations with nanosized particulate materials may contribute to the immunogenicity of this type of biotechnology products. While the immunological properties of engineered nanomaterials and their application as vaccine carriers and adjuvants have been given substantial consideration in themore » current literature, little attention has been paid to nanoparticle immuno- and antigenicity. To fill in this gap, we herein provide an overview of this subject to highlight the current state of the field, review past and present research, and discuss future research directions. - Highlights: • Most engineered nanomaterials are not immunogenic per se. • Generation of nanoparticle-specific antibody can be T-cell dependent or independent. • Antibodies can be generated to particle core, terminal groups or surface coatings. • Engineered and accidental nanomaterials have distinct contribution to immunogenicity. • Tunable physicochemical properties make each nanoparticle unique.« less

  13. Double patterning from design enablement to verification

    NASA Astrophysics Data System (ADS)

    Abercrombie, David; Lacour, Pat; El-Sewefy, Omar; Volkov, Alex; Levine, Evgueni; Arb, Kellen; Reid, Chris; Li, Qiao; Ghosh, Pradiptya

    2011-11-01

    Litho-etch-litho-etch (LELE) is the double patterning (DP) technology of choice for 20 nm contact, via, and lower metal layers. We discuss the unique design and process characteristics of LELE DP, the challenges they present, and various solutions. ∘ We examine DP design methodologies, current DP conflict feedback mechanisms, and how they can help designers identify and resolve conflicts. ∘ In place and route (P&R), the placement engine must now be aware of the assumptions made during IP cell design, and use placement directives provide by the library designer. We examine the new effects DP introduces in detail routing, discuss how multiple choices of LELE and the cut allowances can lead to different solutions, and describe new capabilities required by detail routers and P&R engines. ∘ We discuss why LELE DP cuts and overlaps are critical to optical process correction (OPC), and how a hybrid mechanism of rule and model-based overlap generation can provide a fast and effective solution. ∘ With two litho-etch steps, mask misalignment and image rounding are now verification considerations. We present enhancements to the OPCVerify engine that check for pinching and bridging in the presence of DP overlay errors and acute angles.

  14. Biological approaches for addressing the grand challenge of providing access to clean drinking water.

    PubMed

    Riley, Mark R; Gerba, Charles P; Elimelech, Menachem

    2011-03-31

    The U.S. National Academy of Engineering (NAE) recently published a document presenting "Grand Challenges for Engineering". This list was proposed by leading engineers and scientists from around the world at the request of the U.S. National Science Foundation (NSF). Fourteen topics were selected for these grand challenges, and at least seven can be addressed using the tools and methods of biological engineering. Here we describe how biological engineers can address the challenge of providing access to clean drinking water. This issue must be addressed in part by removing or inactivating microbial and chemical contaminants in order to properly deliver water safe for human consumption. Despite many advances in technologies this challenge is expanding due to increased pressure on fresh water supplies and to new opportunities for growth of potentially pathogenic organisms.

  15. Biological approaches for addressing the grand challenge of providing access to clean drinking water

    PubMed Central

    2011-01-01

    The U.S. National Academy of Engineering (NAE) recently published a document presenting "Grand Challenges for Engineering". This list was proposed by leading engineers and scientists from around the world at the request of the U.S. National Science Foundation (NSF). Fourteen topics were selected for these grand challenges, and at least seven can be addressed using the tools and methods of biological engineering. Here we describe how biological engineers can address the challenge of providing access to clean drinking water. This issue must be addressed in part by removing or inactivating microbial and chemical contaminants in order to properly deliver water safe for human consumption. Despite many advances in technologies this challenge is expanding due to increased pressure on fresh water supplies and to new opportunities for growth of potentially pathogenic organisms. PMID:21453515

  16. 78 FR 13743 - Requirements for the Recognizing Aviation and Aerospace Innovation in Science and Engineering...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-28

    ... Aerospace Innovation in Science and Engineering (RAISE) Award AGENCY: Office of the Secretary, U.S... demonstrate unique, innovative thinking in aerospace science and engineering. With this award, the Secretary... Science and Engineering) Award will recognize innovative scientific and engineering achievements that will...

  17. Making Recycled Paper: An Engineering Design Challenge

    ERIC Educational Resources Information Center

    Song, Ting; Becker, Kurt

    2013-01-01

    Science, technology, engineering, and mathematics (STEM) educators are facing the challenge of attracting more students. The disparity between the need for engineers and the enrollment of engineering students is growing (Genalo, Bruning, & Adams, 2000), and career aspirations of high school students are inconsistent with the employment…

  18. Development of Cryogenic Engine for GSLV MkIII: Technological Challenges

    NASA Astrophysics Data System (ADS)

    Praveen, RS; Jayan, N.; Bijukumar, KS; Jayaprakash, J.; Narayanan, V.; Ayyappan, G.

    2017-02-01

    Cryogenic engine capable of delivering 200 kN thrust is being developed for the first time in the country by ISRO for powering the upper stage of GSLV Mk-III, the next generation launch vehicle of ISRO capable of launching four tonne class satellites to Geo-synchronous Transfer Orbit(GTO). Development of this engine started a decade ago when various sub-systems development and testing were taken up. Starting with injector element development, the design, realization and testing of the major sub-systems viz the gas generator, turbopumps, start-up system and thrust chamber have been successfully done in a phased manner before conducting a series of developmental tests in the integrated engine mode. Apart from the major sub-systems, many critical components like the igniter, control components etc were independently developed and qualified. During the development program many challenges were faced in almost all areas of propulsion engineering. Systems engineering of the engine was another key challenge in the realization. This paper gives an outlook on various technological challenges faced in the key areas related to the engine development, insight to the solutions and measures taken to overcome the challenges.

  19. Incorporating Engineering Design Challenges into STEM Courses

    ERIC Educational Resources Information Center

    Householder, Daniel L., Ed.; Hailey, Christine E., Ed.

    2012-01-01

    Successful strategies for incorporating engineering design challenges into science, technology, engineering, and mathematics (STEM) courses in American high schools are presented in this paper. The developers have taken the position that engineering design experiences should be an important component of the high school education of all American…

  20. Multipurpose electroslag remelting furnace for modern energy and heavy engineering industry

    NASA Astrophysics Data System (ADS)

    Dub, A. V.; Dub, V. S.; Kriger, Yu. N.; Levkov, L. Ya.; Shurygin, D. A.; Kissel'man, M. A.; Nekhamin, C. M.; Chernyak, A. I.; Bessonov, A. V.; Kamantsev, S. V.; Sokolov, S. O.

    2012-12-01

    In 2011, a unique complex based on a multipurpose unit-type electroslag remelting (ESR) furnace is created to meet the demand for large high-quality solid and hollow billets for the products of power, atomic, petrochemical, and heavy machine engineering. This complex has modern low-frequency power supplies with a new control level that ensure a high homogeneity and quality of the billets and an increase in the engineering-and-economical performance of the production. A unique pilot ESR furnace is erected to adjust technological conditions and the main control system elements.

  1. The New Global Responsibilities of Engineers Create Challenges for Engineering Education

    ERIC Educational Resources Information Center

    Fuchs, Willi

    2012-01-01

    Modern societies aim to solve the global challenges of the 21st century with sustainable solutions such as resource efficiency, use of renewable energy sources and recycling. Engineers are called upon to create the cutting edge technological solutions that can help to address these challenges. In developed as well as in developing countries,…

  2. Bulk Magnetization Effects in EMI-Based Classification and Discrimination

    DTIC Science & Technology

    2012-04-01

    response adds to classification performance and ( 2 ) develop a comprehensive understanding of the engineering challenges of primary field cancellation...response adds to classification performance and ( 2 ) develop a comprehensive understanding of the engineering challenges of primary field cancellation...classification performance and ( 2 ) develop a comprehensive understanding of the engineering challenges of primary field cancellation that can support a

  3. The roles of engineering notebooks in shaping elementary engineering student discourse and practice

    NASA Astrophysics Data System (ADS)

    Hertel, Jonathan D.; Cunningham, Christine M.; Kelly, Gregory J.

    2017-06-01

    Engineering design challenges offer important opportunities for students to learn science and engineering knowledge and practices. This study examines how students' engineering notebooks across four units of the curriculum Engineering is Elementary (EiE) support student work during design challenges. Through educational ethnography and discourse analysis, transcripts of student talk and action were created and coded around the uses of notebooks in the accomplishment of engineering tasks. Our coding process identified two broad categories of roles of the notebooks: they scaffold student activity and support epistemic practices of engineering. The study showed the importance of prompts to engage students in effective uses of writing, the roles the notebook assumes in the students' small groups, and the ways design challenges motivate children to write and communicate.

  4. Preparing Engineers for the Challenges of Community Engagement

    ERIC Educational Resources Information Center

    Harsh, Matthew; Bernstein, Michael J.; Wetmore, Jameson; Cozzens, Susan; Woodson, Thomas; Castillo, Rafael

    2017-01-01

    Despite calls to address global challenges through community engagement, engineers are not formally prepared to engage with communities. Little research has been done on means to address this "engagement gap" in engineering education. We examine the efficacy of an intensive, two-day Community Engagement Workshop for engineers, designed…

  5. Iteration in Early-Elementary Engineering Design

    NASA Astrophysics Data System (ADS)

    McFarland Kendall, Amber Leigh

    K-12 standards and curricula are beginning to include engineering design as a key practice within Science Technology Engineering and Mathematics (STEM) education. However, there is little research on how the youngest students engage in engineering design within the elementary classroom. This dissertation focuses on iteration as an essential aspect of engineering design, and because research at the college and professional level suggests iteration improves the designer's understanding of problems and the quality of design solutions. My research presents qualitative case studies of students in kindergarten and third-grade as they engage in classroom engineering design challenges which integrate with traditional curricula standards in mathematics, science, and literature. I discuss my results through the lens of activity theory, emphasizing practices, goals, and mediating resources. Through three chapters, I provide insight into how early-elementary students iterate upon their designs by characterizing the ways in which lesson design impacts testing and revision, by analyzing the plan-driven and experimentation-driven approaches that student groups use when solving engineering design challenges, and by investigating how students attend to constraints within the challenge. I connect these findings to teacher practices and curriculum design in order to suggest methods of promoting iteration within open-ended, classroom-based engineering design challenges. This dissertation contributes to the field of engineering education by providing evidence of productive engineering practices in young students and support for the value of engineering design challenges in developing students' participation and agency in these practices.

  6. 40 CFR 1042.135 - Labeling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... fixed-pitch propellers, etc.). If the engine is certified as a recreational engine, state: “INSTALLING... EMISSIONS FROM NEW AND IN-USE MARINE COMPRESSION-IGNITION ENGINES AND VESSELS Emission Standards and Related Requirements § 1042.135 Labeling. (a) Assign each engine a unique identification number and permanently affix...

  7. 40 CFR 1042.135 - Labeling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... fixed-pitch propellers, etc.). If the engine is certified as a recreational engine, state: “INSTALLING... EMISSIONS FROM NEW AND IN-USE MARINE COMPRESSION-IGNITION ENGINES AND VESSELS Emission Standards and Related Requirements § 1042.135 Labeling. (a) Assign each engine a unique identification number and permanently affix...

  8. 40 CFR 1042.135 - Labeling.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... fixed-pitch propellers, etc.). If the engine is certified as a recreational engine, state: “INSTALLING... EMISSIONS FROM NEW AND IN-USE MARINE COMPRESSION-IGNITION ENGINES AND VESSELS Emission Standards and Related Requirements § 1042.135 Labeling. (a) Assign each engine a unique identification number and permanently affix...

  9. Enabling Engineering Student Success: The Final Report for the Center for the Advancement of Engineering Education. CAEE-TR-10-02

    ERIC Educational Resources Information Center

    Atman, Cynthia J.; Sheppard, Sheri D.; Turns, Jennifer; Adams, Robin S.; Fleming, Lorraine N.; Stevens, Reed; Streveler, Ruth A.; Smith, Karl A.; Miller, Ronald L.; Leifer, Larry J.; Yasuhara, Ken; Lund, Dennis

    2010-01-01

    Today's engineering graduates will solve tomorrow's problems in a world that is advancing faster and facing more critical challenges than ever before. This situation creates significant demand for engineering education to evolve in order to effectively prepare a diverse community of engineers for these challenges. Such concerns have led to the…

  10. A probabilistic approach to randomness in geometric configuration of scalable origami structures

    NASA Astrophysics Data System (ADS)

    Liu, Ke; Paulino, Glaucio; Gardoni, Paolo

    2015-03-01

    Origami, an ancient paper folding art, has inspired many solutions to modern engineering challenges. The demand for actual engineering applications motivates further investigation in this field. Although rooted from the historic art form, many applications of origami are based on newly designed origami patterns to match the specific requirenments of an engineering problem. The application of origami to structural design problems ranges from micro-structure of materials to large scale deployable shells. For instance, some origami-inspired designs have unique properties such as negative Poisson ratio and flat foldability. However, origami structures are typically constrained by strict mathematical geometric relationships, which in reality, can be easily violated, due to, for example, random imperfections introduced during manufacturing, or non-uniform deformations under working conditions (e.g. due to non-uniform thermal effects). Therefore, the effects of uncertainties in origami-like structures need to be studied in further detail in order to provide a practical guide for scalable origami-inspired engineering designs. Through reliability and probabilistic analysis, we investigate the effect of randomness in origami structures on their mechanical properties. Dislocations of vertices of an origami structure have different impacts on different mechanical properties, and different origami designs could have different sensitivities to imperfections. Thus we aim to provide a preliminary understanding of the structural behavior of some common scalable origami structures subject to randomness in their geometric configurations in order to help transition the technology toward practical applications of origami engineering.

  11. Engineered Chimeric Peptides as Antimicrobial Surface Coating Agents toward Infection-Free Implants

    PubMed Central

    Yazici, Hilal; O'Neill, Mary B.; Kacar, Turgay; Wilson, Brandon R.; Oren, E. Emre; Sarikaya, Mehmet; Tamerler, Candan

    2016-01-01

    Prevention of bacterial colonization and consequent biofilm formation remains a major challenge in implantable medical devices. Implant-associated infections are not only a major cause of implant failures but also their conventional treatment with antibiotics brings further complications due to the escalation in multidrug resistance to a variety of bacterial species. Owing to their unique properties, antimicrobial peptides (AMPs) have gained significant attention as effective agents to combat colonization of microorganisms. These peptides have been shown to exhibit a wide spectrum of activities with specificity to a target cell while having a low tendency for developing bacterial resistance. Engineering biomaterial surfaces that feature AMP properties, therefore, offer a promising approach to prevent implant infections. Here, we engineered a chimeric peptide with bifunctionality that both forms a robust solid-surface coating while presenting antimicrobial property. The individual domains of the chimeric peptides were evaluated for their solid-binding kinetics to titanium substrate as well as for their antimicrobial properties in solution. The antimicrobial efficacy of the chimeric peptide on the implant material was evaluated in vitro against infection by a variety of bacteria, including Streptococcus mutans, Staphylococcus. epidermidis, and Escherichia coli, which are commonly found in oral and orthopedic implant related surgeries. Our results demonstrate significant improvement in reducing bacterial colonization onto titanium surfaces below the detectable limit. Engineered chimeric peptides with freely displayed antimicrobial domains could be a potential solution for developing infection-free surfaces by engineering implant interfaces with highly reduced bacterial colonization property. PMID:26795060

  12. Engineered Chimeric Peptides as Antimicrobial Surface Coating Agents toward Infection-Free Implants.

    PubMed

    Yazici, Hilal; O'Neill, Mary B; Kacar, Turgay; Wilson, Brandon R; Oren, E Emre; Sarikaya, Mehmet; Tamerler, Candan

    2016-03-02

    Prevention of bacterial colonization and consequent biofilm formation remains a major challenge in implantable medical devices. Implant-associated infections are not only a major cause of implant failures but also their conventional treatment with antibiotics brings further complications due to the escalation in multidrug resistance to a variety of bacterial species. Owing to their unique properties, antimicrobial peptides (AMPs) have gained significant attention as effective agents to combat colonization of microorganisms. These peptides have been shown to exhibit a wide spectrum of activities with specificity to a target cell while having a low tendency for developing bacterial resistance. Engineering biomaterial surfaces that feature AMP properties, therefore, offer a promising approach to prevent implant infections. Here, we engineered a chimeric peptide with bifunctionality that both forms a robust solid-surface coating while presenting antimicrobial property. The individual domains of the chimeric peptides were evaluated for their solid-binding kinetics to titanium substrate as well as for their antimicrobial properties in solution. The antimicrobial efficacy of the chimeric peptide on the implant material was evaluated in vitro against infection by a variety of bacteria, including Streptococcus mutans, Staphylococcus. epidermidis, and Escherichia coli, which are commonly found in oral and orthopedic implant related surgeries. Our results demonstrate significant improvement in reducing bacterial colonization onto titanium surfaces below the detectable limit. Engineered chimeric peptides with freely displayed antimicrobial domains could be a potential solution for developing infection-free surfaces by engineering implant interfaces with highly reduced bacterial colonization property.

  13. Production of Human Pluripotent Stem Cell Therapeutics Under Defined Xeno-free Conditions: Progress and Challenges

    PubMed Central

    Fan, Yongjia; Wu, Jincheng; Ashok, Preeti; Hsiung, Michael; Tzanakakis, Emmanuel S.

    2014-01-01

    Recent advances on human pluripotent stem cells (hPSCs), including human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) have brought us closer to the realization of their clinical potential. Nonetheless, tissue engineering and regenerative medicine applications will require the generation of hPSC products well beyond the laboratory scale. This also mandates the production of hPSC therapeutics in fully-defined, xeno-free systems and in a reproducible manner. Toward this goal, we summarize current developments in defined media free of animal-derived components for hPSC culture. Bioinspired and synthetic extracellular matrices for the attachment growth and differentiation of hPSCs are also reviewed. Given that most progress in xeno-free medium and substrate development has been demonstrated in two-dimensional rather than three dimensional culture systems, translation from the former to the latter poses unique difficulties. These challenges are discussed in the context of cultivation platforms of hPSCs as aggregates, on microcarriers or after encapsulation in biocompatible scaffolds. PMID:25077810

  14. Production of human pluripotent stem cell therapeutics under defined xeno-free conditions: progress and challenges.

    PubMed

    Fan, Yongjia; Wu, Jincheng; Ashok, Preeti; Hsiung, Michael; Tzanakakis, Emmanuel S

    2015-02-01

    Recent advances on human pluripotent stem cells (hPSCs), including human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) have brought us closer to the realization of their clinical potential. Nonetheless, tissue engineering and regenerative medicine applications will require the generation of hPSC products well beyond the laboratory scale. This also mandates the production of hPSC therapeutics in fully-defined, xeno-free systems and in a reproducible manner. Toward this goal, we summarize current developments in defined media free of animal-derived components for hPSC culture. Bioinspired and synthetic extracellular matrices for the attachment, growth and differentiation of hPSCs are also reviewed. Given that most progress in xeno-free medium and substrate development has been demonstrated in two-dimensional rather than three dimensional culture systems, translation from the former to the latter poses unique difficulties. These challenges are discussed in the context of cultivation platforms of hPSCs as aggregates, on microcarriers or after encapsulation in biocompatible scaffolds.

  15. LESSONS LEARNED IN OPERATING THE HOSE-IN-HOSE SYSTEM FOR TRANSFSERRING SLUDGE AT HANFORDS K-BASINS

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

    PERES MW

    In May 2007, the Department of Energy and the Fluor Hanford K Basin Closure Project completed transferring sludge from the K East Basin to new containers in the K West Basin using a Hose-in-Hose system. This project presented a number of complex and unique technical, operational, and management challenges that had to be resolved to complete the required transfers and satisfy project milestones. The project team (including DOE; regulators; and Fluor management, operations, maintenance, engineering and all other support organizations) found innovative solutions to each challenge. This paper records lessons learned during the operational phase of the sludge transfer viamore » the Hose-In-Hose system. The subject is limited to the operational phase and does not cover design, development, testing or turnover. A discussion of the situation or problem encountered is provided, along with the lesson learned as applicable to a future program or project.« less

  16. Fungal biology and agriculture: revisiting the field

    USGS Publications Warehouse

    Yarden, O.; Ebbole, D.J.; Freeman, S.; Rodriguez, R.J.; Dickman, M. B.

    2003-01-01

    Plant pathology has made significant progress over the years, a process that involved overcoming a variety of conceptual and technological hurdles. Descriptive mycology and the advent of chemical plant-disease management have been followed by biochemical and physiological studies of fungi and their hosts. The later establishment of biochemical genetics along with the introduction of DNA-mediated transformation have set the stage for dissection of gene function and advances in our understanding of fungal cell biology and plant-fungus interactions. Currently, with the advent of high-throughput technologies, we have the capacity to acquire vast data sets that have direct relevance to the numerous subdisciplines within fungal biology and pathology. These data provide unique opportunities for basic research and for engineering solutions to important agricultural problems. However, we also are faced with the challenge of data organization and mining to analyze the relationships between fungal and plant genomes and to elucidate the physiological function of pertinent DNA sequences. We present our perspective of fungal biology and agriculture, including administrative and political challenges to plant protection research.

  17. Challenges Faced by Female-Students in Engineering-Education

    ERIC Educational Resources Information Center

    Madara, Diana Starovoytova; Cherotich, Sharon

    2016-01-01

    Gender-related challenges in learning technical courses are universal phenomenon. These challenges could restrain female students from achieving their fullest potential. The main focus of this study, therefore, is to examine self-recognized challenges faced by undergraduate female students in pursuing engineering at the School of Engineering…

  18. NASA Wearable Technology CLUSTER 2013-2014 Report

    NASA Technical Reports Server (NTRS)

    Simon, Cory; Dunne, Lucy; Zeagler, Clint; Martin, Tom; Pailes-Friedman, Rebecca

    2014-01-01

    Wearable technology has the potential to revolutionize the way humans interact with one another, with information, and with the electronic systems that surround them. This change can already be seen in the dramatic increase in the availability and use of wearable health and activity monitors. These devices continuously monitor the wearer using on-­-body sensors and wireless communication. They provide feedback that can be used to improve physical health and performance. Smart watches and head mounted displays are also receiving a great deal of commercial attention, providing immediate access to information via graphical displays, as well as additional sensing features. For the purposes of the Wearable Technology CLUSTER, wearable technology is broadly defined as any electronic sensing, human interfaces, computing, or communication that is mounted on the body. Current commercially available wearable devices primarily house electronics in rigid packaging to provide protection from flexing, moisture, and other contaminants. NASA mentors are interested in this approach, but are also interested in direct integration of electronics into clothing to enable more comfortable systems. For human spaceflight, wearable technology holds a great deal of promise for significantly improving safety, efficiency, autonomy, and research capacity for the crew in space and support personnel on the ground. Specific capabilities of interest include: Continuous biomedical monitoring for research and detection of health problems. Environmental monitoring for individual exposure assessments and alarms. Activity monitoring for responsive robotics and environments. Multi-modal caution and warning using tactile, auditory, and visual alarms. Wireless, hands-free, on-demand voice communication. Mobile, on-demand access to space vehicle and robotic displays and controls. Many technical challenges must be overcome to realize these wearable technology applications. For example, to make a wearable device that is both functional and comfortable for long duration wear, developers must strive to reduce electronic mass and volume while also addressing constraints imposed by the body attachment method. Depending on the application, the device must be placed in a location that the user can see and reach, and that provides the appropriate access to air and the wearer's skin. Limited power is available from body-­-worn batteries and heat must be managed to prevent discomfort. If the clothing is to be washed, there are additional durability and washability hurdles that traditional electronics are not designed to address. Finally, each specific capability has unique technical challenges that will likely require unique solutions. In addition to the technical challenges, development of wearable devices is made more difficult by the diversity of skills required and the historic lack of collaboration across domains. Wearable technology development requires expertise in textiles engineering, apparel design, software and computer engineering, electronic design and manufacturing, human factors engineering, and application-­-specific fields such as acoustics, medical devices, and sensing. Knowledge from each of these domains must be integrated to create functional and comfortable devices. For this reason, the diversity of knowledge and experience represented in the Wearable Technology is critical to overcoming the fundamental challenges in the field.

  19. Identifying the Challenging Factors in the Transition from Colleges of Engineering to Employment

    ERIC Educational Resources Information Center

    Baytiyeh, Hoda; Naja, Mohamad

    2012-01-01

    The transition from university to a career in engineering is a challenging process. This study examined the perceptions of engineering graduates regarding the difficulties they encountered in their transition from the university to the workplace. Lebanese practising engineers (n=217), living around the world, were surveyed to identify their…

  20. Controlled release of drugs in electrosprayed nanoparticles for bone tissue engineering.

    PubMed

    Jayaraman, Praveena; Gandhimathi, Chinnasamy; Venugopal, Jayarama Reddy; Becker, David Laurence; Ramakrishna, Seeram; Srinivasan, Dinesh Kumar

    2015-11-01

    Generating porous topographic substrates, by mimicking the native extracellular matrix (ECM) to promote the regeneration of damaged bone tissues, is a challenging process. Generally, scaffolds developed for bone tissue regeneration support bone cell growth and induce bone-forming cells by natural proteins and growth factors. Limitations are often associated with these approaches such as improper scaffold stability, and insufficient cell adhesion, proliferation, differentiation, and mineralization with less growth factor expression. Therefore, the use of engineered nanoparticles has been rapidly increasing in bone tissue engineering (BTE) applications. The electrospray technique is advantageous over other conventional methods as it generates nanomaterials of particle sizes in the micro/nanoscale range. The size and charge of the particles are controlled by regulating the polymer solution flow rate and electric voltage. The unique properties of nanoparticles such as large surface area-to-volume ratio, small size, and higher reactivity make them promising candidates in the field of biomedical engineering. These nanomaterials are extensively used as therapeutic agents and for drug delivery, mimicking ECM, and restoring and improving the functions of damaged organs. The controlled and sustained release of encapsulated drugs, proteins, vaccines, growth factors, cells, and nucleotides from nanoparticles has been well developed in nanomedicine. This review provides an insight into the preparation of nanoparticles by electrospraying technique and illustrates the use of nanoparticles in drug delivery for promoting bone tissue regeneration. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Aerospace Ceramic Materials: Thermal, Environmental Barrier Coatings and SiC/SiC Ceramic Matrix Composites for Turbine Engine Applications

    NASA Technical Reports Server (NTRS)

    Zhu, Dongming

    2018-01-01

    Ceramic materials play increasingly important roles in aerospace applications because ceramics have unique properties, including high temperature capability, high stiffness and strengths, excellent oxidation and corrosion resistance. Ceramic materials also generally have lower densities as compared to metallic materials, making them excellent candidates for light-weight hot-section components of aircraft turbine engines, rocket exhaust nozzles, and thermal protection systems for space vehicles when they are being used for high-temperature and ultra-high temperature ceramics applications. Ceramic matrix composites (CMCs), including non-oxide and oxide CMCs, are also recently being incorporated in gas turbine engines for high pressure and high temperature section components and exhaust nozzles. However, the complexity and variability of aerospace ceramic processing methods, compositions and microstructures, the relatively low fracture toughness of the ceramic materials, still remain the challenging factors for ceramic component design, validation, life prediction, and thus broader applications. This ceramic material section paper presents an overview of aerospace ceramic materials and their characteristics. A particular emphasis has been placed on high technology level (TRL) enabling ceramic systems, that is, turbine engine thermal and environmental barrier coating systems and non-oxide type SiC/SiC CMCs. The current status and future trend of thermal and environmental barrier coatings and SiC/SiC CMC development and applications are described.

  2. Programmable Hydrogels for Cell Encapsulation and Neo-Tissue Growth to Enable Personalized Tissue Engineering.

    PubMed

    Bryant, Stephanie J; Vernerey, Franck J

    2018-01-01

    Biomimetic and biodegradable synthetic hydrogels are emerging as a promising platform for cell encapsulation and tissue engineering. Notably, synthetic-based hydrogels offer highly programmable macroscopic properties (e.g., mechanical, swelling and transport properties) and degradation profiles through control over several tunable parameters (e.g., the initial network structure, degradation kinetics and behavior, and polymer properties). One component to success is the ability to maintain structural integrity as the hydrogel transitions to neo-tissue. This seamless transition is complicated by the fact that cellular activity is highly variable among donors. Thus, computational models provide an important tool in tissue engineering due to their unique ability to explore the coupled processes of hydrogel degradation and neo-tissue growth across multiple length scales. In addition, such models provide new opportunities to develop predictive computational tools to overcome the challenges with designing hydrogels for different donors. In this report, programmable properties of synthetic-based hydrogels and their relation to the hydrogel's structural properties and their evolution with degradation are reviewed. This is followed by recent progress on the development of computational models that describe hydrogel degradation with neo-tissue growth when cells are encapsulated in a hydrogel. Finally, the potential for predictive models to enable patient-specific hydrogel designs for personalized tissue engineering is discussed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Metabolic engineering of plant oils and waxes for use as industrial feedstocks.

    PubMed

    Vanhercke, Thomas; Wood, Craig C; Stymne, Sten; Singh, Surinder P; Green, Allan G

    2013-02-01

    Society has come to rely heavily on mineral oil for both energy and petrochemical needs. Plant lipids are uniquely suited to serve as a renewable source of high-value fatty acids for use as chemical feedstocks and as a substitute for current petrochemicals. Despite the broad variety of acyl structures encountered in nature and the cloning of many genes involved in their biosynthesis, attempts at engineering economic levels of specialty industrial fatty acids in major oilseed crops have so far met with only limited success. Much of the progress has been hampered by an incomplete knowledge of the fatty acid biosynthesis and accumulation pathways. This review covers new insights based on metabolic flux and reverse engineering studies that have changed our view of plant oil synthesis from a mostly linear process to instead an intricate network with acyl fluxes differing between plant species. These insights are leading to new strategies for high-level production of industrial fatty acids and waxes. Furthermore, progress in increasing the levels of oil and wax structures in storage and vegetative tissues has the potential to yield novel lipid production platforms. The challenge and opportunity for the next decade will be to marry these technologies when engineering current and new crops for the sustainable production of oil and wax feedstocks. © 2012 CSIRO Plant Biotechnology Journal © 2012 Society for Experimental Biology, Association of Applied Biologists and Blackwell Publishing Ltd.

  4. Mitigating Climate Change at the Carbon Water Nexus: A Call to Action for the Environmental Engineering Community

    PubMed Central

    Clarens, Andres F.; Peters, Catherine A.

    2016-01-01

    Abstract Environmental engineers have played a critical role in improving human and ecosystem health over the past several decades. These contributions have focused on providing clean water and air as well as managing waste streams and remediating polluted sites. As environmental problems have become more global in scale and more deeply entrenched in sociotechnical systems, the discipline of environmental engineering must grow to be ready to respond to the challenges of the coming decades. Here we make the case that environmental engineers should play a leadership role in the development of climate change mitigation technologies at the carbon-water nexus (CWN). Climate change, driven largely by unfettered emissions of fossil carbon into the atmosphere, is a far-reaching and enormously complex environmental risk with the potential to negatively affect food security, human health, infrastructure, and other systems. Solving this problem will require a massive mobilization of existing and innovative new technology. The environmental engineering community is uniquely positioned to do pioneering work at the CWN using a skillset that has been honed, solving related problems. The focus of this special issue, on “The science and innovation of emerging subsurface energy technologies,” provides one example domain within which environmental engineers and related disciplines are beginning to make important contributions at the CWN. In this article, we define the CWN and describe how environmental engineers can bring their considerable expertise to bear in this area. Then we review some of the topics that appear in this special issue, for example, mitigating the impacts of hydraulic fracturing and geologic carbon storage, and we provide perspective on emergent research directions, for example, enhanced geothermal energy, energy storage in sedimentary formations, and others. PMID:28031695

  5. Mitigating Climate Change at the Carbon Water Nexus: A Call to Action for the Environmental Engineering Community.

    PubMed

    Clarens, Andres F; Peters, Catherine A

    2016-10-01

    Environmental engineers have played a critical role in improving human and ecosystem health over the past several decades. These contributions have focused on providing clean water and air as well as managing waste streams and remediating polluted sites. As environmental problems have become more global in scale and more deeply entrenched in sociotechnical systems, the discipline of environmental engineering must grow to be ready to respond to the challenges of the coming decades. Here we make the case that environmental engineers should play a leadership role in the development of climate change mitigation technologies at the carbon-water nexus (CWN). Climate change, driven largely by unfettered emissions of fossil carbon into the atmosphere, is a far-reaching and enormously complex environmental risk with the potential to negatively affect food security, human health, infrastructure, and other systems. Solving this problem will require a massive mobilization of existing and innovative new technology. The environmental engineering community is uniquely positioned to do pioneering work at the CWN using a skillset that has been honed, solving related problems. The focus of this special issue, on "The science and innovation of emerging subsurface energy technologies," provides one example domain within which environmental engineers and related disciplines are beginning to make important contributions at the CWN. In this article, we define the CWN and describe how environmental engineers can bring their considerable expertise to bear in this area. Then we review some of the topics that appear in this special issue, for example, mitigating the impacts of hydraulic fracturing and geologic carbon storage, and we provide perspective on emergent research directions, for example, enhanced geothermal energy, energy storage in sedimentary formations, and others.

  6. Women in engineering conference: capitalizing on today`s challenges

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

    Metz, S.S.; Martins, S.M.

    This document contains the conference proceedings of the Women in Engineering Conference: Capitalizing on Today`s Challenges, held June 1-4, 1996 in Denver, Colorado. Topics included engineering and science education, career paths, workplace issues, and affirmative action.

  7. Future of Chemical Engineering: Integrating Biology into the Undergraduate ChE Curriculum

    ERIC Educational Resources Information Center

    Mosto, Patricia; Savelski, Mariano; Farrell, Stephanie H.; Hecht, Gregory B.

    2007-01-01

    Integrating biology in the chemical engineering curriculum seems to be the future for chemical engineering programs nation and worldwide. Rowan University's efforts to address this need include a unique chemical engineering curriculum with an intensive biology component integrated throughout from freshman to senior years. Freshman and Sophomore…

  8. Biodegradable Polyphosphazene-Based Blends for Regenerative Engineering

    PubMed Central

    Ogueri, Kenneth S.; Escobar Ivirico, Jorge L.; Nair, Lakshmi S.; Allcock, Harry R.; Laurencin, Cato T.

    2017-01-01

    The occurrence of musculoskeletal tissue injury or disease and the subsequent functional impairment is at an alarming rate. It continues to be one of the most challenging problems in the human health care. Regenerative engineering offers a promising transdisciplinary strategy for tissues regeneration based on the convergence of tissue engineering, advanced materials science, stem cell science, developmental biology and clinical translation. Biomaterials are emerging as extracellular-mimicking matrices designed to provide instructive cues to control cell behavior and ultimately, be applied as therapies to regenerate damaged tissues. Biodegradable polymers constitute an attractive class of biomaterials for the development of scaffolds due to their flexibility in chemistry and the ability to be excreted or resorbed by the body. Herein, the focus will be on biodegradable polyphosphazene-based blend systems. The synthetic flexibility of polyphosphazene, combined with the unique inorganic backbone, has provided a springboard for more research and subsequent development of numerous novel materials that are capable of forming miscible blends with poly (lactide-co-glycolide) (PLAGA). Laurencin and co-workers has demonstrated the exploitation of the synthetic flexibility of Polyphosphazene that will allow the design of novel polymers, which can form miscible blends with PLAGA for biomedical applications. These novel blends, due to their well-tuned biodegradability, and mechanical and biological properties coupled with the buffering capacity of the degradation products, constitute ideal materials for regeneration of various musculoskeletal tissues. Lay Summary Regenerative engineering aims to regenerate complex tissues to address the clinical challenge of organ damage. Tissue engineering has largely focused on the restoration and repair of individual tissues and organs, but over the past 25 years, scientific, engineering, and medical advances have led to the introduction of this new approach which involves the regeneration of complex tissues and biological systems such as a knee or a whole limb. While a number of excellent advanced biomaterials have been developed, the choice of biomaterials, however, has increased over the past years to include polymers that can be designed with a range of mechanical properties, degradation rates, and chemical functionality. The polyphosphazenes are one good example. Their chemical versatility and hydrogen bonding capability encourages blending with other biologically relevant polymers. The further development of Polyphosphazene-based blends will present a wide spectrum of advanced biomaterials that can be used as scaffolds for regenerative engineering and as well as other biomedical applications. PMID:28596987

  9. Biodegradable Polyphosphazene-Based Blends for Regenerative Engineering.

    PubMed

    Ogueri, Kenneth S; Escobar Ivirico, Jorge L; Nair, Lakshmi S; Allcock, Harry R; Laurencin, Cato T

    2017-03-01

    The occurrence of musculoskeletal tissue injury or disease and the subsequent functional impairment is at an alarming rate. It continues to be one of the most challenging problems in the human health care. Regenerative engineering offers a promising transdisciplinary strategy for tissues regeneration based on the convergence of tissue engineering, advanced materials science, stem cell science, developmental biology and clinical translation. Biomaterials are emerging as extracellular-mimicking matrices designed to provide instructive cues to control cell behavior and ultimately, be applied as therapies to regenerate damaged tissues. Biodegradable polymers constitute an attractive class of biomaterials for the development of scaffolds due to their flexibility in chemistry and the ability to be excreted or resorbed by the body. Herein, the focus will be on biodegradable polyphosphazene-based blend systems. The synthetic flexibility of polyphosphazene, combined with the unique inorganic backbone, has provided a springboard for more research and subsequent development of numerous novel materials that are capable of forming miscible blends with poly (lactide-co-glycolide) (PLAGA). Laurencin and co-workers has demonstrated the exploitation of the synthetic flexibility of Polyphosphazene that will allow the design of novel polymers, which can form miscible blends with PLAGA for biomedical applications. These novel blends, due to their well-tuned biodegradability, and mechanical and biological properties coupled with the buffering capacity of the degradation products, constitute ideal materials for regeneration of various musculoskeletal tissues. Regenerative engineering aims to regenerate complex tissues to address the clinical challenge of organ damage. Tissue engineering has largely focused on the restoration and repair of individual tissues and organs, but over the past 25 years, scientific, engineering, and medical advances have led to the introduction of this new approach which involves the regeneration of complex tissues and biological systems such as a knee or a whole limb. While a number of excellent advanced biomaterials have been developed, the choice of biomaterials, however, has increased over the past years to include polymers that can be designed with a range of mechanical properties, degradation rates, and chemical functionality. The polyphosphazenes are one good example. Their chemical versatility and hydrogen bonding capability encourages blending with other biologically relevant polymers. The further development of Polyphosphazene-based blends will present a wide spectrum of advanced biomaterials that can be used as scaffolds for regenerative engineering and as well as other biomedical applications.

  10. The Emerging Field of RNA Nanotechnology

    PubMed Central

    Guo, Peixuan

    2011-01-01

    RNA can be designed and manipulated just like DNA while having different rules for base-pairing and displaying functions similar to proteins. The large variety of loops and motifs in RNA allow them to fold into numerous complicated structures. This diversity provides a platform for identifying viable building blocks for particle assemblies, substrate binding and manufacture engineering. RNA thermal stability allows production of multivalent nanostructures with defined stoichiometry. Here we review the unique qualities of RNA nanotechnology and their distinct properties inside the body. We describe techniques for constructing RNA nanoparticles from different building blocks and their applications in nanomedicine. Finally, we discuss challenges in predicting and synthesizing RNA and offer some perspectives on the yield and cost of RNA production. PMID:21102465

  11. Unlocking the Potential of Poly(Ortho Ester)s: A General Catalytic Approach to the Synthesis of Surface‐Erodible Materials

    PubMed Central

    Tschan, Mathieu J.‐L.; Ieong, Nga Sze; Todd, Richard; Everson, Jack

    2017-01-01

    Abstract Poly(ortho ester)s (POEs) are well‐known for their surface‐eroding properties and hence present unique opportunities for controlled‐release and tissue‐engineering applications. Their development and wide‐spread investigation has, however, been severely limited by challenging synthetic requirements that incorporate unstable intermediates and are therefore highly irreproducible. Herein, the first catalytic method for the synthesis of POEs using air‐ and moisture‐stable vinyl acetal precursors is presented. The synthesis of a range of POE structures is demonstrated, including those that are extremely difficult to achieve by other synthetic methods. Furthermore, application of this chemistry permits efficient installation of functional groups through ortho ester linkages on an aliphatic polycarbonate. PMID:29087610

  12. Smart Fluid Systems: The Advent of Autonomous Liquid Robotics.

    PubMed

    Chiolerio, A; Quadrelli, Marco B

    2017-07-01

    Organic, inorganic or hybrid devices in the liquid state, kept in a fixed volume by surface tension or by a confining membrane that protects them from a harsh environment, could be used as biologically inspired autonomous robotic systems with unique capabilities. They could change shape according to a specific exogenous command or by means of a fully integrated adaptive system, and provide an innovative solution for many future applications, such as space exploration in extreme or otherwise challenging environments, post-disaster search and rescue in ground applications, compliant wearable devices, and even in the medical field for in vivo applications. This perspective provides an initial assessment of existing capabilities that could be leveraged to pursue the topic of "Smart Fluid Systems" or "Liquid Engineered Systems".

  13. Transitioning Rationally Designed Catalytic Materials to Real 'Working' Catalysts Produced at Commercial Scale: Nanoparticle Materials

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

    Schaidle, Joshua A.; Habas, Susan E.; Baddour, Frederick G.

    Catalyst design, from idea to commercialization, requires multi-disciplinary scientific and engineering research and development over 10-20 year time periods. Historically, the identification of new or improved catalyst materials has largely been an empirical trial-and-error process. However, advances in computational capabilities (new tools and increased processing power) coupled with new synthetic techniques have started to yield rationally-designed catalysts with controlled nano-structures and tailored properties. This technological advancement represents an opportunity to accelerate the catalyst development timeline and to deliver new materials that outperform existing industrial catalysts or enable new applications, once a number of unique challenges associated with the scale-up ofmore » nano-structured materials are overcome.« less

  14. Requirements for facilities and measurement techniques to support CFD development for hypersonic aircraft

    NASA Technical Reports Server (NTRS)

    Sellers, William L., III; Dwoyer, Douglas L.

    1992-01-01

    The design of a hypersonic aircraft poses unique challenges to the engineering community. Problems with duplicating flight conditions in ground based facilities have made performance predictions risky. Computational fluid dynamics (CFD) has been proposed as an additional means of providing design data. At the present time, CFD codes are being validated based on sparse experimental data and then used to predict performance at flight conditions with generally unknown levels of uncertainty. This paper will discuss the facility and measurement techniques that are required to support CFD development for the design of hypersonic aircraft. Illustrations are given of recent success in combining experimental and direct numerical simulation in CFD model development and validation for hypersonic perfect gas flows.

  15. Distributed computation: the new wave of synthetic biology devices.

    PubMed

    Macía, Javier; Posas, Francesc; Solé, Ricard V

    2012-06-01

    Synthetic biology (SB) offers a unique opportunity for designing complex molecular circuits able to perform predefined functions. But the goal of achieving a flexible toolbox of reusable molecular components has been shown to be limited due to circuit unpredictability, incompatible parts or random fluctuations. Many of these problems arise from the challenges posed by engineering the molecular circuitry: multiple wires are usually difficult to implement reliably within one cell and the resulting systems cannot be reused in other modules. These problems are solved by means of a nonstandard approach to single cell devices, using cell consortia and allowing the output signal to be distributed among different cell types, which can be combined in multiple, reusable and scalable ways. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Carbon Nanotubes in Biomedical Applications: Factors, Mechanisms, and Remedies of Toxicity.

    PubMed

    Alshehri, Reem; Ilyas, Asad Muhammad; Hasan, Anwarul; Arnaout, Adnan; Ahmed, Farid; Memic, Adnan

    2016-09-22

    Carbon nanotubes (CNTs) represent one of the most studied allotropes of carbon. The unique physicochemical properties of CNTs make them among prime candidates for numerous applications in biomedical fields including drug delivery, gene therapy, biosensors, and tissue engineering applications. However, toxicity of CNTs has been a major concern for their use in biomedical applications. In this review, we present an overview of carbon nanotubes in biomedical applications; we particularly focus on various factors and mechanisms affecting their toxicity. We have discussed various parameters including the size, length, agglomeration, and impurities of CNTs that may cause oxidative stress, which is often the main mechanism of CNTs' toxicity. Other toxic pathways are also examined, and possible ways to overcome these challenges have been discussed.

  17. Multi-level Simulation of a Real Time Vibration Monitoring System Component

    NASA Technical Reports Server (NTRS)

    Robertson, Bryan A.; Wilkerson, Delisa

    2005-01-01

    This paper describes the development of a custom built Digital Signal Processing (DSP) printed circuit board designed to implement the Advanced Real Time Vibration Monitoring Subsystem proposed by Marshall Space Flight Center (MSFC) Transportation Directorate in 2000 for the Space Shuttle Main Engine Advanced Health Management System (AHMS). This Real Time Vibration Monitoring System (RTVMS) is being developed for ground use as part of the AHMS Health Management Computer-Integrated Rack Assembly (HMC-IRA). The HMC-IRA RTVMS design contains five DSPs which are highly interconnected through individual communication ports, shared memory, and a unique communication router that allows all the DSPs to receive digitized data fiom two multi-channel analog boards simultaneously. This paper will briefly cover the overall board design but will focus primarily on the state-of-the-art simulation environment within which this board was developed. This 16-layer board with over 1800 components and an additional mezzanine card has been an extremely challenging design. Utilization of a Mentor Graphics simulation environment provided the unique board and system level simulation capability to ascertain any timing or functional concerns before production. By combining VHDL, Synopsys Software and Hardware Models, and the Mentor Design Capture Environment, multiple simulations were developed to verify the RTVMS design. This multi-level simulation allowed the designers to achieve complete operability without error the first time the RTVMS printed circuit board was powered. The HMC-IRA design has completed all engineering and deliverable unit testing. P

  18. Multi-level Simulation of a Real Time Vibration Monitoring System Component

    NASA Technical Reports Server (NTRS)

    Roberston, Bryan; Wilkerson, DeLisa

    2004-01-01

    This paper describes the development of a custom built Digital Signal Processing (DSP) printed circuit board designed to implement the Advanced Real Time Vibration Monitoring Subsystem proposed by MSFC Transportation Directorate in 2000 for the Space Shuttle Main Engine Advanced Health Management System (AHMS). This Real Time Vibration Monitoring System (RTVMS) is being developed for ground use as part of the AHMS Health Management Computer-Integrated Rack Assembly (HMC-IRA). The HMC-IRA RTVMS design contains five DSPs which are highly interconnected through individual communication ports, shared memory, and a unique communication router that allows all the DSPs to receive digitized data from two multi-channel analog boards simultaneously. This paper will briefly cover the overall board design but will focus primarily on the state-of-the-art simulation environment within which this board was developed. This 16-layer board with over 1800 components and an additional mezzanine card has been an extremely challenging design. Utilization of a Mentor Graphics simulation environment provided the unique board and system level simulation capability to ascertain any timing or functional concerns before production. By combining VHDL, Synopsys Software and Hardware Models, and the Mentor Design Capture Environment, multiple simulations were developed to verify the RTVMS design. This multi-level simulation allowed the designers to achieve complete operability without error the first time the RTVMS printed circuit board was powered. The HMCIRA design has completed all engineering unit testing and the deliverable unit is currently under development.

  19. A predictive machine learning approach for microstructure optimization and materials design

    NASA Astrophysics Data System (ADS)

    Liu, Ruoqian; Kumar, Abhishek; Chen, Zhengzhang; Agrawal, Ankit; Sundararaghavan, Veera; Choudhary, Alok

    2015-06-01

    This paper addresses an important materials engineering question: How can one identify the complete space (or as much of it as possible) of microstructures that are theoretically predicted to yield the desired combination of properties demanded by a selected application? We present a problem involving design of magnetoelastic Fe-Ga alloy microstructure for enhanced elastic, plastic and magnetostrictive properties. While theoretical models for computing properties given the microstructure are known for this alloy, inversion of these relationships to obtain microstructures that lead to desired properties is challenging, primarily due to the high dimensionality of microstructure space, multi-objective design requirement and non-uniqueness of solutions. These challenges render traditional search-based optimization methods incompetent in terms of both searching efficiency and result optimality. In this paper, a route to address these challenges using a machine learning methodology is proposed. A systematic framework consisting of random data generation, feature selection and classification algorithms is developed. Experiments with five design problems that involve identification of microstructures that satisfy both linear and nonlinear property constraints show that our framework outperforms traditional optimization methods with the average running time reduced by as much as 80% and with optimality that would not be achieved otherwise.

  20. ASME Material Challenges for Advanced Reactor Concepts

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

    Piyush Sabharwall; Ali Siahpush

    2013-07-01

    This study presents the material Challenges associated with Advanced Reactor Concept (ARC) such as the Advanced High Temperature Reactor (AHTR). ACR are the next generation concepts focusing on power production and providing thermal energy for industrial applications. The efficient transfer of energy for industrial applications depends on the ability to incorporate cost-effective heat exchangers between the nuclear heat transport system and industrial process heat transport system. The heat exchanger required for AHTR is subjected to a unique set of conditions that bring with them several design challenges not encountered in standard heat exchangers. The corrosive molten salts, especially at highermore » temperatures, require materials throughout the system to avoid corrosion, and adverse high-temperature effects such as creep. Given the very high steam generator pressure of the supercritical steam cycle, it is anticipated that water tube and molten salt shell steam generators heat exchanger will be used. In this paper, the ASME Section III and the American Society of Mechanical Engineers (ASME) Section VIII requirements (acceptance criteria) are discussed. Also, the ASME material acceptance criteria (ASME Section II, Part D) for high temperature environment are presented. Finally, lack of ASME acceptance criteria for thermal design and analysis are discussed.« less

  1. Engineering's Grand Challenges: Priorities and Integration Recommendations for Technology Education Curriculum Development

    ERIC Educational Resources Information Center

    Buelin, Jennifer; Clark, Aaron C.; Ernst, Jeremy V.

    2016-01-01

    In this study, the 14 Grand Challenges for Engineering in the 21st Century identified by the National Academy of Engineering were examined by a panel of experts in an effort to identify prospective curricular integration opportunities in the field of technology and engineering education. The study utilized a three-round modified Delphi methodology…

  2. A unique nuclear thermal rocket engine using a particle bed reactor

    NASA Astrophysics Data System (ADS)

    Culver, Donald W.; Dahl, Wayne B.; McIlwain, Melvin C.

    1992-01-01

    Aerojet Propulsion Division (APD) studied 75-klb thrust Nuclear Thermal Rocket Engines (NTRE) with particle bed reactors (PBR) for application to NASA's manned Mars mission and prepared a conceptual design description of a unique engine that best satisfied mission-defined propulsion requirements and customer criteria. This paper describes the selection of a sprint-type Mars transfer mission and its impact on propulsion system design and operation. It shows how our NTRE concept was developed from this information. The resulting, unusual engine design is short, lightweight, and capable of high specific impulse operation, all factors that decrease Earth to orbit launch costs. Many unusual features of the NTRE are discussed, including nozzle area ratio variation and nozzle closure for closed loop after cooling. Mission performance calculations reveal that other well known engine options do not support this mission.

  3. Update - Concept of Operations for Integrated Model-Centric Engineering at JPL

    NASA Technical Reports Server (NTRS)

    Bayer, Todd J.; Bennett, Matthew; Delp, Christopher L.; Dvorak, Daniel; Jenkins, Steven J.; Mandutianu, Sanda

    2011-01-01

    The increasingly ambitious requirements levied on JPL's space science missions, and the development pace of such missions, challenge our current engineering practices. All the engineering disciplines face this growth in complexity to some degree, but the challenges are greatest in systems engineering where numerous competing interests must be reconciled and where complex system level interactions must be identified and managed. Undesired system-level interactions are increasingly a major risk factor that cannot be reliably exposed by testing, and natural-language single-viewpoint specifications areinadequate to capture and expose system level interactions and characteristics. Systems engineering practices must improve to meet these challenges, and the most promising approach today is the movement toward a more integrated and model-centric approach to mission conception, design, implementation and operations. This approach elevates engineering models to a principal role in systems engineering, gradually replacing traditional document centric engineering practices.

  4. "Artificial humans": Psychology and neuroscience perspectives on embodiment and nonverbal communication.

    PubMed

    Vogeley, Kai; Bente, Gary

    2010-01-01

    "Artificial humans", so-called "Embodied Conversational Agents" and humanoid robots, are assumed to facilitate human-technology interaction referring to the unique human capacities of interpersonal communication and social information processing. While early research and development in artificial intelligence (AI) focused on processing and production of natural language, the "new AI" has also taken into account the emotional and relational aspects of communication with an emphasis both on understanding and production of nonverbal behavior. This shift in attention in computer science and engineering is reflected in recent developments in psychology and social cognitive neuroscience. This article addresses key challenges which emerge from the goal to equip machines with socio-emotional intelligence and to enable them to interpret subtle nonverbal cues and to respond to social affordances with naturally appearing behavior from both perspectives. In particular, we propose that the creation of credible artificial humans not only defines the ultimate test for our understanding of human communication and social cognition but also provides a unique research tool to improve our knowledge about the underlying psychological processes and neural mechanisms. Copyright © 2010. Published by Elsevier Ltd.

  5. Design of a High Temperature Radiator for the Variable Specific Impulse Magnetoplasma Rocket

    NASA Technical Reports Server (NTRS)

    Sheth, Rubik B.; Ungar, Eugene K.; Chambliss, Joe P.

    2012-01-01

    The Variable Specific Impulse Magnetoplasma Rocket (VASIMR), currently under development by Ad Astra Rocket Company (Webster, TX), is a unique propulsion system that could change the way space propulsion is performed. VASIMR's efficiency, when compared to that of a conventional chemical rocket, reduces the propellant needed for exploration missions by a factor of 10. Currently plans include flight tests of a 200 kW VASIMR system, titled VF-200, on the International Space Station (ISS). The VF-200 will consist of two 100 kW thruster units packaged together in one engine bus. Each thruster core generates 27 kW of waste heat during its 15 minute firing time. The rocket core will be maintained between 283 and 573 K by a pumped thermal control loop. The design of a high temperature radiator is a unique challenge for the vehicle design. This paper will discuss the path taken to develop a steady state and transient-based radiator design. The paper will describe the radiator design option selected for the VASIMR thermal control system for use on ISS, and how the system relates to future exploration vehicles.

  6. Engineering the LISA Project: Systems Engineering Challenges

    NASA Technical Reports Server (NTRS)

    Evans, Jordan P.

    2006-01-01

    The Laser Interferometer Space Antenna (LISA) is a joint NASA/ESA mission to detect and measure gravitational waves with periods from 1 s to 10000 s. The systems engineering challenges of developing a giant interferometer, 5 million kilometers on a side, an: numerous. Some of the key challenges are presented in this paper. The organizational challenges imposed by sharing the engineering function between three centers (ESA ESTEC, NASA GSFC, and JPL) across nine time zones are addressed. The issues and approaches to allocation of the acceleration noise and measurement sensitivity budget terms across a traditionally decomposed system are discussed. Additionally, using LISA to detect gravitational waves for the first time presents significant data analysis challenges, many of which drive the project system design. The approach to understanding the implications of science data analysis on the system is also addressed.

  7. Building an Evaluation Strategy for an Integrated Curriculum in Chemical Engineering

    ERIC Educational Resources Information Center

    McCarthy, Joseph J.; Parker, Robert S.; Abatan, Adetola; Besterfield-Sacre, Mary

    2011-01-01

    Increasing knowledge integration has gained wide-spread support as an important goal in engineering education. The Chemical Engineering Pillars curriculum at the University of Pittsburgh, unique for its use of block scheduling, is one of the first four-year, integrated curricula in engineering, and is specifically designed to facilitate knowledge…

  8. Addressing the Grand Challenge of atmospheric carbon dioxide: geologic sequestration vs. biological recycling

    PubMed Central

    2011-01-01

    On February 15, 2008, the National Academy of Engineering unveiled their list of 14 Grand Challenges for Engineering. Building off of tremendous advancements in the past century, these challenges were selected for their role in assuring a sustainable existence for the rapidly increasing global community. It is no accident that the first five Challenges on the list involve the development of sustainable energy sources and management of environmental resources. While the focus of this review is to address the single Grand Challenge of "develop carbon sequestration methods", is will soon be clear that several other Challenges are intrinsically tied to it through the principles of sustainability. How does the realm of biological engineering play a role in addressing these Grand Challenges? PMID:22047501

  9. New Challenging Approaches to Engineering Education: Enhancing University-Industry Co-Operation

    ERIC Educational Resources Information Center

    Korhonen-Yrjanheikki, Kati; Tukiainen, Taina; Takala, Minna

    2007-01-01

    Globalization, accelerated time-based competition, qualitative dynamics, rapid development of technology and especially Information and Communications Technology (ICT) developments challenge engineering education and capability development of each engineer. The success and the competitiveness of companies are increasingly based on their employees.…

  10. Reflections of a Faraday Challenge Day Leader

    ERIC Educational Resources Information Center

    Sewell, Keira

    2014-01-01

    Keira Sewell has just finished her second year as a Challenge Leader for the Faraday Challenge, a STEM-based scheme run by the Institution of Engineering and Technology. Aimed at 12-13 year-old students, its purpose is to engage students in future careers in engineering. Each year, a new challenge is held in over sixty schools and universities…

  11. Multiple dopant injection system for small rocket engines

    NASA Technical Reports Server (NTRS)

    Sakala, G. G.; Raines, N. G.

    1992-01-01

    The Diagnostics Test Facility (DTF) at NASA's Stennis Space Center (SSC) was designed and built to provide a standard rocket engine exhaust plume for use in the research and development of engine health monitoring instrumentation. A 1000 lb thrust class liquid oxygen (LOX)-gaseous hydrogen (GH2) fueled rocket engine is used as the subscale plume source to simulate the SSME during experimentation and instrument development. The ability of the DTF to provide efficient, and low cost test operations makes it uniquely suited for plume diagnostic experimentation. The most unique feature of the DTF is the Multiple Dopant Injection System (MDIS) that is used to seed the exhaust plume with the desired element or metal alloy. The dopant injection takes place at the fuel injector, yielding a very uniform and homogeneous distribution of the seeding material in the exhaust plume. The MDIS allows during a single test firing of the DTF, the seeding of the exhaust plume with up to three different dopants and also provides distilled water base lines between the dopants. A number of plume diagnostic-related experiments have already utilized the unique capabilities of the DTF.

  12. Engineering craniofacial structures: facing the challenge.

    PubMed

    Zaky, S H; Cancedda, R

    2009-12-01

    The human innate regenerative ability is known to be limited by the intensity of the insult together with the availability of progenitor cells, which may cause certain irreparable damage. It is only recently that the paradigm of tissue engineering found its way to the treatment of irreversibly affected body structures with the challenge of reconstructing the lost part. In the current review, we underline recent trials that target engineering of human craniofacial structures, mainly bone, cartilage, and teeth. We analyze the applied engineering strategies relative to the selection of cell types to lay down a specific targeted tissue, together with their association with an escorting scaffold for a particular engineered site, and discuss their necessity to be sustained by growth factors. Challenges and expectations for facial skeletal engineering are discussed in the context of future treatment.

  13. A concept ideation framework for medical device design.

    PubMed

    Hagedorn, Thomas J; Grosse, Ian R; Krishnamurty, Sundar

    2015-06-01

    Medical device design is a challenging process, often requiring collaboration between medical and engineering domain experts. This collaboration can be best institutionalized through systematic knowledge transfer between the two domains coupled with effective knowledge management throughout the design innovation process. Toward this goal, we present the development of a semantic framework for medical device design that unifies a large medical ontology with detailed engineering functional models along with the repository of design innovation information contained in the US Patent Database. As part of our development, existing medical, engineering, and patent document ontologies were modified and interlinked to create a comprehensive medical device innovation and design tool with appropriate properties and semantic relations to facilitate knowledge capture, enrich existing knowledge, and enable effective knowledge reuse for different scenarios. The result is a Concept Ideation Framework for Medical Device Design (CIFMeDD). Key features of the resulting framework include function-based searching and automated inter-domain reasoning to uniquely enable identification of functionally similar procedures, tools, and inventions from multiple domains based on simple semantic searches. The significance and usefulness of the resulting framework for aiding in conceptual design and innovation in the medical realm are explored via two case studies examining medical device design problems. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Redirecting adenovirus tropism by genetic, chemical, and mechanical modification of the adenovirus surface for cancer gene therapy.

    PubMed

    Yoon, A-Rum; Hong, Jinwoo; Kim, Sung Wan; Yun, Chae-Ok

    2016-06-01

    Despite remarkable advancements, clinical evaluations of adenovirus (Ad)-mediated cancer gene therapies have highlighted the need for improved delivery and targeting. Genetic modification of Ad capsid proteins has been extensively attempted. Although genetic modification enhances the therapeutic potential of Ad, it is difficult to successfully incorporate extraneous moieties into the capsid and the engineering process is laborious. Recently, chemical modification of the Ad surface with nanomaterials and targeting moieties has been found to enhance Ad internalization into the target by both passive and active mechanisms. Alternatively, external stimulus-mediated targeting can result in selective accumulation of Ad in the tumor and prevent dissemination of Ad into surrounding nontarget tissues. In the present review, we discuss various genetic, chemical, and mechanical engineering strategies for overcoming the challenges that hinder the therapeutic efficacy of Ad-based approaches. Surface modification of Ad by genetic, chemical, or mechanical engineering strategies enables Ad to overcome the shortcomings of conventional Ad and enhances delivery efficiency through distinct and unique mechanisms that unmodified Ad cannot mimic. However, although the therapeutic potential of Ad-mediated gene therapy has been enhanced by various surface modification strategies, each strategy still possesses innate limitations that must be addressed, requiring innovative ideas and designs.

  15. Fabrication of the Advanced X-ray Astrophysics Facility (AXAF) Optics: A Deterministic, Precision Engineering Approach to Optical Fabrication

    NASA Technical Reports Server (NTRS)

    Gordon, T. E.

    1995-01-01

    The mirror assembly of the AXAF observatory consists of four concentric, confocal, Wolter type 1 telescopes. Each telescope includes two conical grazing incidence mirrors, a paraboloid followed by a hyperboloid. Fabrication of these state-or-the-art optics is now complete, with predicted performance that surpasses the goals of the program. The fabrication of these optics, whose size and requirements exceed those of any previous x-ray mirrors, presented a challenging task requiring the use of precision engineering in many different forms. Virtually all of the equipment used for this effort required precision engineering. Accurate metrology required deterministic support of the mirrors in order to model the gravity distortions which will not be present on orbit. The primary axial instrument, known as the Precision Metrology Station (PMS), was a unique scanning Fizeau interferometer. After metrology was complete, the optics were placed in specially designed Glass Support Fixtures (GSF's) for installation on the Automated Cylindrical Grinder/Polishers (ACG/P's). The GSF's were custom molded for each mirror element to match the shape of the outer surface to minimize distortions of the inner surface. The final performance of the telescope is expected to far exceed the original goals and expectations of the program.

  16. Suicide Gene-Engineered Stromal Cells Reveal a Dynamic Regulation of Cancer Metastasis

    NASA Astrophysics Data System (ADS)

    Shen, Keyue; Luk, Samantha; Elman, Jessica; Murray, Ryan; Mukundan, Shilpaa; Parekkadan, Biju

    2016-02-01

    Cancer-associated fibroblasts (CAFs) are a major cancer-promoting component in the tumor microenvironment (TME). The dynamic role of human CAFs in cancer progression has been ill-defined because human CAFs lack a unique marker needed for a cell-specific, promoter-driven knockout model. Here, we developed an engineered human CAF cell line with an inducible suicide gene to enable selective in vivo elimination of human CAFs at different stages of xenograft tumor development, effectively circumventing the challenge of targeting a cell-specific marker. Suicide-engineered CAFs were highly sensitive to apoptosis induction in vitro and in vivo by the addition of a simple small molecule inducer. Selection of timepoints for targeted CAF apoptosis in vivo during the progression of a human breast cancer xenograft model was guided by a bi-phasic host cytokine response that peaked at early timepoints after tumor implantation. Remarkably, we observed that the selective apoptosis of CAFs at these early timepoints did not affect primary tumor growth, but instead increased the presence of tumor-associated macrophages and the metastatic spread of breast cancer cells to the lung and bone. The study revealed a dynamic relationship between CAFs and cancer metastasis that has counter-intuitive ramifications for CAF-targeted therapy.

  17. Two-phase unsaturated flow at Yucca Mountain, Nevada: A report on current understanding

    NASA Astrophysics Data System (ADS)

    Pruess, Karsten

    Thick unsaturated zones in semi-arid regions have some unique attributes that are favorable for long-term isolation of hazardous wastes. The disposal concept at Yucca Mountain takes advantage of low ambient water fluxes. Evaluation of site suitability must be based on an understanding of two-phase (liquid-gas) fluid flow and heat transfer processes in a heterogeneous, fractured rock mass. A large body of relevant knowledge has been accumulated in various fields, including petroleum and geothermal reservoir engineering, chemical engineering, civil engineering, and soil science. Complications at Yucca Mountain arise from the partly episodic and localized nature of water seepage in fracture networks. This limits the applicability of spatial and temporal averaging, and poses great challenges for numerical modeling. Significant flow and heat transfer effects may occur in the gas phase. Observations of natural and man-made chemical tracers as well as controlled field experiments have provided much useful information on mass transport at Yucca Mountain, including the occurrence of fast preferential flow. It is now clear that fracture-matrix interactions are considerably weaker than would be expected from a concept of water flowing in fractures as areally extensive sheets. The Yucca Mountain system is expected to be quite robust in coping with larger seepage rates, as may occur under future more pluvial climatic conditions.

  18. Redefining Scientist-Educator Partnerships: Science in Service at Stanford

    NASA Astrophysics Data System (ADS)

    Beck, K.

    2005-05-01

    The Stanford Solar Observatories Group and Haas Center for Public Service have created an innovative model for scientist-educator partnerships in which science students are trained and mentored by public service education professionals to create outreach events for local communities. The program, Science in Service, is part of the EPO plan for the Solar Group's participation in NASA's Solar Dynamics Observatory mission. Based on the principles of service learning, the Science in Service Program mentors college science students in best practices for communicating science and engages these students in public service projects that center on teaching solar science. The program goals are to - Enhance and expand the learning experiences that pre-college students, from underserved and underrepresented groups in particular, have in science and technology. - Promote leadership in community service in the area of science and engineering among the next generation of scientists and engineers, today's undergraduate students. - Encourage science and engineering faculty to think creatively about their outreach requirements and to create a community of faculty committed to quality outreach programs. This talk will describe the unique advantages and challenges of a research-public service partnership, explain the structure of Stanford's Science in Service Program, and present the experiences of the undergraduates and the outreach communities that have been involved in the program.

  19. Engineers Without Borders Australia--lessons learned from an innovative approach to the upgrade of water supply infrastructure in Tenganan, Indonesia.

    PubMed

    Third, K; Fun, O M; Bowen, J; Micenko, A; Grey, V; Prohasky, T

    2009-01-01

    The community of Tenganan in eastern Bali, Indonesia, has requested technical assistance from Engineers Without Borders Australia (EWB) to improve the quantity and quality of water delivered through their water supply system. This is a unique development project in which the Tenganan people have identified their own needs and developed their own conceptual solution to the problem. For the first time, EWB is undertaking the design phase for the water system by an off-shore design team and project assistance team (PAT) based in Australia. This allows EWB to draw on resources and experience of EWB members and their employing companies in Australia. It also enables young engineers to develop skills and experience in development work without having to leave the country. However, the innovative approach also presented significant challenges to the project members, particularly in establishing appropriate design criteria and the co-ordination of simultaneous activities across Australia. This paper describes the approach taken by EWB and makes a preliminary assessment of the benefits and limitations inherent in this approach. The overall aim of the project is to produce a successful "bottom-up" development action that will deliver a sustainable solution to the Tenganan community.

  20. Design and manufacture of neural tissue engineering scaffolds using hyaluronic acid and polycaprolactone nanofibers with controlled porosity.

    PubMed

    Entekhabi, Elahe; Haghbin Nazarpak, Masoumeh; Moztarzadeh, Fathollah; Sadeghi, Ali

    2016-12-01

    Given the large differences in nervous tissue and other tissues of the human body and its unique features, such as poor and/or lack of repair, there are many challenges in the repair process of this tissue. Tissue engineering is one of the most effective approaches to repair neural damages. Scaffolds made from electrospun fibers have special potential in cell adhesion, function and cell proliferation. This research attempted to design a high porous nanofibrous scaffold using hyaluronic acid and polycaprolactone to provide ideal conditions for nerve regeneration by applying proper physicochemical and mechanical signals. Chemical and mechanical properties of pure PCL and PCL/HA nanofibrous scaffolds were measured by FTIR and tensile test. Morphology, swelling behavior, and biodegradability of the scaffolds were evaluated too. Porosity of various layers of scaffolds was measured by image analysis method. To assess the cell-scaffold interaction, SH-SY5Y human neuroblastoma cell line were cultured on the electrospun scaffolds. Taken together, these results suggest that the blended nanofibrous scaffolds PCL/HA 95:5 exhibit the most balanced properties to meet all of the required specifications for neural cells and have potential application in neural tissue engineering. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Reverse engineering and analysis of large genome-scale gene networks

    PubMed Central

    Aluru, Maneesha; Zola, Jaroslaw; Nettleton, Dan; Aluru, Srinivas

    2013-01-01

    Reverse engineering the whole-genome networks of complex multicellular organisms continues to remain a challenge. While simpler models easily scale to large number of genes and gene expression datasets, more accurate models are compute intensive limiting their scale of applicability. To enable fast and accurate reconstruction of large networks, we developed Tool for Inferring Network of Genes (TINGe), a parallel mutual information (MI)-based program. The novel features of our approach include: (i) B-spline-based formulation for linear-time computation of MI, (ii) a novel algorithm for direct permutation testing and (iii) development of parallel algorithms to reduce run-time and facilitate construction of large networks. We assess the quality of our method by comparison with ARACNe (Algorithm for the Reconstruction of Accurate Cellular Networks) and GeneNet and demonstrate its unique capability by reverse engineering the whole-genome network of Arabidopsis thaliana from 3137 Affymetrix ATH1 GeneChips in just 9 min on a 1024-core cluster. We further report on the development of a new software Gene Network Analyzer (GeNA) for extracting context-specific subnetworks from a given set of seed genes. Using TINGe and GeNA, we performed analysis of 241 Arabidopsis AraCyc 8.0 pathways, and the results are made available through the web. PMID:23042249

  2. The Radical Flank Effect and Cross-occupational Collaboration for Technology Development during a Power Shift.

    PubMed

    Truelove, Emily; Kellogg, Katherine C

    2016-12-01

    This 12-month ethnographic study of an early entrant into the U.S. car-sharing industry demonstrates that when an organization shifts its focus from developing radical new technology to incrementally improving this technology, the shift may spark an internal power struggle between the dominant engineering group and a challenger occupational group such as the marketing group. Analyzing 42 projects in two time periods that required collaboration between engineering and marketing during such a shift, we show how cross-occupational collaboration under these conditions can be facilitated by a radical flank threat, through which the bargaining power of moderates is strengthened by the presence of a more-radical group. In the face of a strong threat by radical members of a challenger occupational group, moderate members of the dominant engineering group may change their perceptions of their power to resist challengers' demands and begin to distinguish between the goals of radical versus more-moderate challengers. To maintain as much power as possible and prevent the more-dramatic change in engineering occupational goals demanded by radical challengers, moderate engineers may build a coalition with moderate challengers and collaborate for incremental technology development.

  3. Creative Thinking of Practical Engineering Students During a Design Project

    NASA Astrophysics Data System (ADS)

    Waks, Shlomo; Merdler, Moti

    2003-01-01

    Creativity in engineering design had become an economic necessity and not merely the privilege of unique individuals. The search for new, innovative and effective ideas in engineering design stands in center of daily creative performance. This search requires sensitivity to gaps of knowledge and information, and the ability to evoke numerous, different and unique ideas about engineering problems. The source of such information or knowledge can be either extrinsic-such as provided by an instructor or expert or intrinsic, which might involve transformation from one field or context to another. Furthermore, interaction with an exterior source as well as developing an inherent drive, have an impact on the motivation to perform creatively. This article, which is based on a study conducted among Israeli practical engineering students, deals with the variations in creative thinking during various stages of a design project and the relation between creative thinking and motivation factors.

  4. Scalable graphene production: perspectives and challenges of plasma applications

    NASA Astrophysics Data System (ADS)

    Levchenko, Igor; Ostrikov, Kostya (Ken); Zheng, Jie; Li, Xingguo; Keidar, Michael; B. K. Teo, Kenneth

    2016-05-01

    Graphene, a newly discovered and extensively investigated material, has many unique and extraordinary properties which promise major technological advances in fields ranging from electronics to mechanical engineering and food production. Unfortunately, complex techniques and high production costs hinder commonplace applications. Scaling of existing graphene production techniques to the industrial level without compromising its properties is a current challenge. This article focuses on the perspectives and challenges of scalability, equipment, and technological perspectives of the plasma-based techniques which offer many unique possibilities for the synthesis of graphene and graphene-containing products. The plasma-based processes are amenable for scaling and could also be useful to enhance the controllability of the conventional chemical vapour deposition method and some other techniques, and to ensure a good quality of the produced graphene. We examine the unique features of the plasma-enhanced graphene production approaches, including the techniques based on inductively-coupled and arc discharges, in the context of their potential scaling to mass production following the generic scaling approaches applicable to the existing processes and systems. This work analyses a large amount of the recent literature on graphene production by various techniques and summarizes the results in a tabular form to provide a simple and convenient comparison of several available techniques. Our analysis reveals a significant potential of scalability for plasma-based technologies, based on the scaling-related process characteristics. Among other processes, a greater yield of 1 g × h-1 m-2 was reached for the arc discharge technology, whereas the other plasma-based techniques show process yields comparable to the neutral-gas based methods. Selected plasma-based techniques show lower energy consumption than in thermal CVD processes, and the ability to produce graphene flakes of various sizes reaching hundreds of square millimetres, and the thickness varying from a monolayer to 10-20 layers. Additional factors such as electrical voltage and current, not available in thermal CVD processes could potentially lead to better scalability, flexibility and control of the plasma-based processes. Advantages and disadvantages of various systems are also considered.

  5. Scalable graphene production: perspectives and challenges of plasma applications.

    PubMed

    Levchenko, Igor; Ostrikov, Kostya Ken; Zheng, Jie; Li, Xingguo; Keidar, Michael; B K Teo, Kenneth

    2016-05-19

    Graphene, a newly discovered and extensively investigated material, has many unique and extraordinary properties which promise major technological advances in fields ranging from electronics to mechanical engineering and food production. Unfortunately, complex techniques and high production costs hinder commonplace applications. Scaling of existing graphene production techniques to the industrial level without compromising its properties is a current challenge. This article focuses on the perspectives and challenges of scalability, equipment, and technological perspectives of the plasma-based techniques which offer many unique possibilities for the synthesis of graphene and graphene-containing products. The plasma-based processes are amenable for scaling and could also be useful to enhance the controllability of the conventional chemical vapour deposition method and some other techniques, and to ensure a good quality of the produced graphene. We examine the unique features of the plasma-enhanced graphene production approaches, including the techniques based on inductively-coupled and arc discharges, in the context of their potential scaling to mass production following the generic scaling approaches applicable to the existing processes and systems. This work analyses a large amount of the recent literature on graphene production by various techniques and summarizes the results in a tabular form to provide a simple and convenient comparison of several available techniques. Our analysis reveals a significant potential of scalability for plasma-based technologies, based on the scaling-related process characteristics. Among other processes, a greater yield of 1 g × h(-1) m(-2) was reached for the arc discharge technology, whereas the other plasma-based techniques show process yields comparable to the neutral-gas based methods. Selected plasma-based techniques show lower energy consumption than in thermal CVD processes, and the ability to produce graphene flakes of various sizes reaching hundreds of square millimetres, and the thickness varying from a monolayer to 10-20 layers. Additional factors such as electrical voltage and current, not available in thermal CVD processes could potentially lead to better scalability, flexibility and control of the plasma-based processes. Advantages and disadvantages of various systems are also considered.

  6. Engineering Education and Students' Challenges: Strategies toward Enhancing the Educational Environment in Engineering Colleges

    ERIC Educational Resources Information Center

    Alkandari, Nabila Y.

    2014-01-01

    The main goal of this research is to gain an understanding of the challenges which have to be confronted by the engineering students at the College of Engineering and Petroleum at Kuwait University. The college has a large number of students, of which three hundred and eighty five were selected on a random basis for study purposes. The results…

  7. Project Morpheus Main Engine Development and Preliminary Flight Testing

    NASA Technical Reports Server (NTRS)

    Morehead, Robert L.

    2011-01-01

    A LOX/Methane rocket engine was developed for a prototype terrestrial lander and then used to fly the lander at Johnson Space Center. The development path of this engine is outlined, including unique items such as variable acoustic damping and variable film cooling.

  8. Shaping Nanoparticles with Hydrophilic Compositions and Hydrophobic Properties as Nanocarriers for Antibiotic Delivery

    PubMed Central

    2015-01-01

    Inspired by the lotus effect in nature, surface roughness engineering has led to novel materials and applications in many fields. Despite the rapid progress in superhydrophobic and superoleophobic materials, this concept of Mother Nature’s choice is yet to be applied in the design of advanced nanocarriers for drug delivery. Pioneering work has emerged in the development of nanoparticles with rough surfaces for gene delivery; however, the preparation of nanoparticles with hydrophilic compositions but with enhanced hydrophobic property at the nanoscale level employing surface topology engineering remains a challenge. Herein we report for the first time the unique properties of mesoporous hollow silica (MHS) nanospheres with controlled surface roughness. Compared to MHS with a smooth surface, rough mesoporous hollow silica (RMHS) nanoparticles with the same hydrophilic composition show unusual hydrophobicity, leading to higher adsorption of a range of hydrophobic molecules and controlled release of hydrophilic molecules. RMHS loaded with vancomycin exhibits an enhanced antibacterial effect. Our strategy provides a new pathway in the design of novel nanocarriers for diverse bioapplications. PMID:27162988

  9. The unique challenge of managing an undergraduate Get-Away-Special experiment

    NASA Technical Reports Server (NTRS)

    Roming, Peter W. A.; Spute, Mark K.; Williams, Memorie K.

    1992-01-01

    A group of Bringham Young University (BYU) undergraduate students has undertaken an experiment to design and build a normal incidence soft x ray robotics telescope for solar observations. The design phase of this, GOLDHELOX project, has now been completed and final construction and modifications are in progress. The design and manufacture of the payload is under the direction of team leaders and a system's integrator. A goal of this project is educating and furnishing experiences in space engineering and physics for undergraduate students. Our main source of funding is NASA and the BYU Colleges of Physical and Mathematical Sciences and Engineering and Technology. This project is possible because of the NASA Get-Away Special (GAS) program. The only feasible alternative is using an expensive sounding rocket. We estimate the sun tracking and guidance package alone would cost upwards of a million dollars -- at least ten times our entire budget. Because of the GAS program, we simplified the construction, operation, and programming of the instruments with resulting savings in weight, cost, and time spent.

  10. Socio-Cultural Challenges in Global Software Engineering Education

    ERIC Educational Resources Information Center

    Hoda, Rashina; Babar, Muhammad Ali; Shastri, Yogeshwar; Yaqoob, Humaa

    2017-01-01

    Global software engineering education (GSEE) is aimed at providing software engineering (SE) students with knowledge, skills, and understanding of working in globally distributed arrangements so they can be prepared for the global SE (GSE) paradigm. It is important to understand the challenges involved in GSEE for improving the quality and…

  11. Implementing Inclusive Engineering Challenges for Elementary Students

    ERIC Educational Resources Information Center

    Silva Mangiante, Elaine; Moore, Adam

    2015-01-01

    The Next Generation Science Standards emphasize the need to promote equitable opportunities for all students to engage in science and engineering. This article offers eight tips that educators can use to support students of all abilities, including those with special learning needs, to engage in engineering challenges at the elementary level.

  12. Why Research-Informed Teaching in Engineering Education? A Review of the Evidence

    ERIC Educational Resources Information Center

    Bubou, Gordon Monday; Offor, Ibebietei Temple; Bappa, Abubakar Saddiq

    2017-01-01

    Challenges of today's engineering education (EE) are emergent, necessitating calls for its reformation to empower future engineers function optimally as innovative leaders, in both local and international contexts. These challenges: keeping pace with technological dynamism; high attrition; and most importantly, quality teaching/learning require…

  13. Exploring Engineering--Pros Can Help Make It Real

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2008-01-01

    Engineering is one of the oldest professions, dating back to humanity's early times. The Seven Wonders of the Ancient World were all primarily feats of engineering. Most also had profound social/cultural impacts. Engineers are agents of change, devotees of capitalism, and dreamers of the possible. They are also in a unique position to work with…

  14. Web Design for Space Operations: An Overview of the Challenges and New Technologies Used in Developing and Operating Web-Based Applications in Real-Time Operational Support Onboard the International Space Station, in Astronaut Mission Planning and Mission Control Operations

    NASA Technical Reports Server (NTRS)

    Khan, Ahmed

    2010-01-01

    The International Space Station (ISS) Operations Planning Team, Mission Control Centre and Mission Automation Support Network (MAS) have all evolved over the years to use commercial web-based technologies to create a configurable electronic infrastructure to manage the complex network of real-time planning, crew scheduling, resource and activity management as well as onboard document and procedure management required to co-ordinate ISS assembly, daily operations and mission support. While these Web technologies are classified as non-critical in nature, their use is part of an essential backbone of daily operations on the ISS and allows the crew to operate the ISS as a functioning science laboratory. The rapid evolution of the internet from 1998 (when ISS assembly began) to today, along with the nature of continuous manned operations in space, have presented a unique challenge in terms of software engineering and system development. In addition, the use of a wide array of competing internet technologies (including commercial technologies such as .NET and JAVA ) and the special requirements of having to support this network, both nationally among various control centres for International Partners (IPs), as well as onboard the station itself, have created special challenges for the MCC Web Tools Development Team, software engineers and flight controllers, who implement and maintain this system. This paper presents an overview of some of these operational challenges, and the evolving nature of the solutions and the future use of COTS based rich internet technologies in manned space flight operations. In particular this paper will focus on the use of Microsoft.s .NET API to develop Web-Based Operational tools, the use of XML based service oriented architectures (SOA) that needed to be customized to support Mission operations, the maintenance of a Microsoft IIS web server onboard the ISS, The OpsLan, functional-oriented Web Design with AJAX

  15. Microfabrication of hierarchical structures for engineered mechanical materials

    NASA Astrophysics Data System (ADS)

    Vera Canudas, Marc

    Materials found in nature present, in some cases, unique properties from their constituents that are of great interest in engineered materials for applications ranging from structural materials for the construction of bridges, canals and buildings to the fabrication of new lightweight composites for airplane and automotive bodies, to protective thin film coatings, amongst other fields. Research in the growing field of biomimetic materials indicates that the micro-architectures present in natural materials are critical to their macroscopic mechanical properties. A better understanding of the effect that structure and hierarchy across scales have on the material properties will enable engineered materials with enhanced properties. At the moment, very few theoretical models predict mechanical properties of simple materials based on their microstructures. Moreover these models are based on observations from complex biological systems. One way to overcome this challenge is through the use of microfabrication techniques to design and fabricate simple materials, more appropriate for the study of hierarchical organizations and microstructured materials. Arrays of structures with controlled geometry and dimension can be designed and fabricated at different length scales, ranging from a few hundred nanometers to centimeters, in order to mimic similar systems found in nature. In this thesis, materials have been fabricated in order to gain fundamental insight into the complex hierarchical materials found in nature and to engineer novel materials with enhanced mechanical properties. The materials fabricated here were mechanically characterized and compared to simple mechanics models to describe their behavior with the goal of applying the knowledge acquired to the design and synthesis of future engineered materials with novel properties.

  16. Institutional Memory Preservation at NASA Glenn Research Center

    NASA Technical Reports Server (NTRS)

    Coffey, J.; Moreman, Douglas; Dyer, J.; Hemminger, J. A.

    1999-01-01

    In this era of downsizing and deficit reduction, the preservation of institutional memory is a widespread concern for U.S. companies and governmental agencies. The National Aeronautical and Space Administration faces the pending retirement of many of the agency's long-term, senior engineers. NASA has a marvelous long-term history of success, but the agency faces a recurring problem caused by the loss of these engineers' unique knowledge and perspectives on NASA's role in aeronautics and space exploration. The current work describes a knowledge elicitation effort aimed at demonstrating the feasibility of preserving the more personal, heuristic knowledge accumulated over the years by NASA engineers, as contrasted with the "textbook" knowledge of launch vehicles. Work on this project was performed at NASA Glenn Research Center and elsewhere, and focused on launch vehicle systems integration. The initial effort was directed toward an historic view of the Centaur upper stage which is powered by two RL-10 engines. Various experts were consulted, employing a variety of knowledge elicitation techniques, regarding the Centaur and RL-10. Their knowledge is represented in searchable Web-based multimedia presentations. This paper discusses the various approaches to knowledge elicitation and knowledge representation employed, and assesses successes and challenges in trying to perform large-scale knowledge preservation of institutional memory. It is anticipated that strategies for knowledge elicitation and representation that have been developed in this grant will be utilized to elicit knowledge in a variety of domains including the complex heuristics that underly use of simulation software packages such as that being explored in the Expert System Architecture for Rocket Engine Numerical Simulators.

  17. Characterizing and engineering tunable spin functionality inside indium arsenide/gallium arsenide quantum dot molecules

    NASA Astrophysics Data System (ADS)

    Liu, Weiwen

    The continual downsizing of the basic functional units used in the electronics industry has motivated the study of the quantum computation and related topics. To overcome the limitations of classical physics and engineering, some unique quantum mechanical features, especially entanglement and superpositions have begun to be considered as important properties for future bits. Including these quantum mechanical features is attractive because the ability to utilize quantum mechanics can dramatically enhance computational power. Among the various ways of constructing the basic building blocks for quantum computation, we are particularly interested in using spins inside epitaxially grown InAs/GaAs quantum dot molecules as quantum bits (qubits). The ability to design and engineer nanostructures with tailored quantum properties is critical to engineering quantum computers and other novel electro-optical devices and is one of the key challenges for scaling up new ideas for device application. In this thesis, we will focus on how the structure and composition of quantum dot molecules can be used to control spin properties and charge interactions. Tunable spin and charge properties can enable new, more scalable, methods of initializing and manipulating quantum information. In this thesis, we demonstrate one method to enable electric-field tunability of Zeeman splitting for a single electron spin inside a quantum dot molecules by using heterostructure engineering techniques to modify the barrier that separates quantum dots. We describe how these structural changes to the quantum dot molecules also change charge interactions and propose ways to use this effect to enable accurate measurement of coulomb interactions and possibly charge occupancy inside these complicated quantum dot molecules.

  18. New Mass Properties Engineers Aerospace Ballasting Challenge Facilitated by the SAWE Community

    NASA Technical Reports Server (NTRS)

    Cutright, Amanda; Shaughnessy, Brendan

    2010-01-01

    The discipline of Mass Properties Engineering tends to find the engineers; not typically vice versa. In this case, two engineers quickly found their new responsibilities deep in many aspects of mass properties engineering and required to meet technical challenges in a fast paced environment. As part of NASA's Constellation Program, a series of flight tests will be conducted to evaluate components of the new spacecraft launch vehicles. One of these tests is the Pad Abort 1 (PA-1) flight test which will test the Launch Abort System (LAS), a system designed to provide escape for astronauts in the event of an emergency. The Flight Test Articles (FTA) used in this flight test are required to match mass properties corresponding to the operational vehicle, which has a continually evolving design. Additionally, since the structure and subsystems for the Orion Crew Module (CM) FTA are simplified versions of the final product, thousands of pounds of ballast are necessary to achieve the desired mass properties. These new mass properties engineers are responsible for many mass properties aspects in support of the flight test, including meeting the ballasting challenge for the CM Boilerplate FTA. SAWE expert and experienced mass properties engineers, both those that are directly on the team and many that supported via a variety of Society venues, significantly contributed to facilitating the success of addressing this particular mass properties ballasting challenge, in addition to many other challenges along the way. This paper discusses the details regarding the technical aspects of this particular mass properties challenge, as well as identifies recommendations for new mass properties engineers that were learned from the SAWE community along the way.

  19. Development of the Functional Flow Block Diagram for the J-2X Rocket Engine System

    NASA Technical Reports Server (NTRS)

    White, Thomas; Stoller, Sandra L.; Greene, WIlliam D.; Christenson, Rick L.; Bowen, Barry C.

    2007-01-01

    The J-2X program calls for the upgrade of the Apollo-era Rocketdyne J-2 engine to higher power levels, using new materials and manufacturing techniques, and with more restrictive safety and reliability requirements than prior human-rated engines in NASA history. Such requirements demand a comprehensive systems engineering effort to ensure success. Pratt & Whitney Rocketdyne system engineers performed a functional analysis of the engine to establish the functional architecture. J-2X functions were captured in six major operational blocks. Each block was divided into sub-blocks or states. In each sub-block, functions necessary to perform each state were determined. A functional engine schematic consistent with the fidelity of the system model was defined for this analysis. The blocks, sub-blocks, and functions were sequentially numbered to differentiate the states in which the function were performed and to indicate the sequence of events. The Engine System was functionally partitioned, to provide separate and unique functional operators. Establishing unique functional operators as work output of the System Architecture process is novel in Liquid Propulsion Engine design. Each functional operator was described such that its unique functionality was identified. The decomposed functions were then allocated to the functional operators both of which were the inputs to the subsystem or component performance specifications. PWR also used a novel approach to identify and map the engine functional requirements to customer-specified functions. The final result was a comprehensive Functional Flow Block Diagram (FFBD) for the J-2X Engine System, decomposed to the component level and mapped to all functional requirements. This FFBD greatly facilitates component specification development, providing a well-defined trade space for functional trades at the subsystem and component level. It also provides a framework for function-based failure modes and effects analysis (FMEA), and a rigorous baseline for the functional architecture.

  20. Quantitative Approaches to Group Research: Suggestions for Best Practices

    ERIC Educational Resources Information Center

    McCarthy, Christopher J.; Whittaker, Tiffany A.; Boyle, Lauren H.; Eyal, Maytal

    2017-01-01

    Rigorous scholarship is essential to the continued growth of group work, yet the unique nature of this counseling specialty poses challenges for quantitative researchers. The purpose of this proposal is to overview unique challenges to quantitative research with groups in the counseling field, including difficulty in obtaining large sample sizes…

  1. High-End Computing Challenges in Aerospace Design and Engineering

    NASA Technical Reports Server (NTRS)

    Bailey, F. Ronald

    2004-01-01

    High-End Computing (HEC) has had significant impact on aerospace design and engineering and is poised to make even more in the future. In this paper we describe four aerospace design and engineering challenges: Digital Flight, Launch Simulation, Rocket Fuel System and Digital Astronaut. The paper discusses modeling capabilities needed for each challenge and presents projections of future near and far-term HEC computing requirements. NASA's HEC Project Columbia is described and programming strategies presented that are necessary to achieve high real performance.

  2. Formal Abstraction in Engineering Education--Challenges and Technology Support

    ERIC Educational Resources Information Center

    Neuper, Walther A.

    2017-01-01

    This is a position paper in the field of Engineering Education, which is at the very beginning in Europe. It relates challenges in the new field to the emerging technology of (Computer) Theorem Proving (TP). Experience shows, that "teaching" abstract models, for instance the wave equation in mechanical engineering and in electrical…

  3. Embedding Enterprise in Science and Engineering Departments

    ERIC Educational Resources Information Center

    Handscombe, Robert D.; Rodriguez-Falcon, Elena; Patterson, Eann A.

    2008-01-01

    Purpose: This paper aims to focus on the attempts to implement the challenges of teaching enterprise to science and engineering students by the embedding approach chosen by the White Rose Centre for Enterprise (WRCE), one of the centres formed under the Science Engineering Challenge in the UK. Design/methodology/approach: WRCE's objective was to…

  4. A History of Welding on the Space Shuttle Main Engine (1975 to 2010)

    NASA Technical Reports Server (NTRS)

    Zimmerman, Frank R.; Russell, Carolyn K.

    2010-01-01

    The Space Shuttle Main Engine (SSME) is a high performance, throttleable, liquid hydrogen fueled rocket engine. High thrust and specific impulse (Isp) are achieved through a staged combustion engine cycle, combined with high combustion pressure (approx.3000psi) generated by the two-stage pump and combustion process. The SSME is continuously throttleable from 67% to 109% of design thrust level. The design criteria for this engine maximize performance and weight, resulting in a 7,800 pound rocket engine that produces over a half million pounds of thrust in vacuum with a specific impulse of 452/sec. It is the most reliable rocket engine in the world, accumulating over one million seconds of hot-fire time and achieving 100% flight success in the Space Shuttle program. A rocket engine with the unique combination of high reliability, performance, and reusability comes at the expense of manufacturing simplicity. Several innovative design features and fabrication techniques are unique to this engine. This is as true for welding as any other manufacturing process. For many of the weld joints it seemed mean cheating physics and metallurgy to meet the requirements. This paper will present a history of the welding used to produce the world s highest performance throttleable rocket engine.

  5. Postharvest technology for developing countries: challenges and opportunities in research, outreach and advocacy.

    PubMed

    Kitinoja, Lisa; Saran, Sunil; Roy, Susanta K; Kader, Adel A

    2011-03-15

    This article discusses the needs and challenges of developing good, science-based, simple methods for postharvest handling that can be made available in developing countries. Some of the traditional challenges have been successfully met (i.e. identifying causes and sources of losses for key crops, identifying many potential postharvest technologies of practical use for reducing losses), but many challenges remain. These include the characterization of indigenous crops in terms of their unique postharvest physiology (e.g. respiration rate, susceptibility to water loss, chilling sensitivity, ethylene sensitivity), ascertaining the differences between handling recommendations made for well-known varieties and the needs of local varieties of crops, and determining cost effectiveness of scale-appropriate postharvest technologies in each locale and for each crop. Key issues include building capacity at the local level in postharvest science, university teaching and extension, and continued adaptive research efforts to match emerging postharvest technologies to local needs as these continue to change over time. Development of appropriate postharvest technology relies upon many disciplines that are relevant to the overall success of horticulture, i.e. plant biology, engineering, agricultural economics, food processing, nutrition, food safety, and environmental conservation. The expanding pool of new information derived from postharvest research and outreach efforts in these areas can lead in many directions which are likely to have an impact on relieving poverty in developing countries. Copyright © 2011 Society of Chemical Industry.

  6. Issues with the Application of Thermographic Phosphors to Measure High Temperatures in a Gas Turbine Engines

    NASA Astrophysics Data System (ADS)

    Khalid, A. H.; Kontis, K.

    2009-01-01

    The demand for more efficient engines is increasing as concerns over greenhouse gases continue to grow. Performance can be increased if higher turbine inlet temperatures are achieved. However, this increases the chance of material failure. Therefore, the optimum temperature is prescribed by the balance between the benefits of thermal efficiency and material life. To ensure safety and reliability, uncertainty in temperature measurement forces the engine to be operated below its thermal design limit. Accurate surface measurement offers the potential to increase engine performance by allowing them to operate closer to this limit. It can allow designers to better understand flow physics, and greatly facilitate the testing and development of newer thermal protection systems and concepts. The aim of this paper is to highlight the motivations of using phosphor thermometry in gas turbine environments as an alternative to current measurement methods such as discrete thermocouple measurements and pyrometry. Phosphor thermometry offers many advantages over conventional techniques. However, the harsh, high temperature and fast rotating environment presents some unique challenges and the paper further aims to discuss the issues that would arise in such environments. There will be increasing blackbody radiation, restrictions to optical access and time available to collect emissions. There will be imposed upper and lower temperature limits and other restrictions that will greatly influence the design of the measurement system, including the choice of phosphor, bonding technique, excitation and detection methodologies. A system would have to be bespoke to suit the end measurement goal.

  7. 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

  8. Feasibility of Large High-Powered Solar Electric Propulsion Vehicles: Issues and Solutions

    NASA Technical Reports Server (NTRS)

    Capadona, Lynn A.; Woytach, Jeffrey M.; Kerslake, Thomas W.; Manzella, David H.; Christie, Robert J.; Hickman, Tyler A.; Schneidegger, Robert J.; Hoffman, David J.; Klem, Mark D.

    2012-01-01

    Human exploration beyond low Earth orbit will require the use of enabling technologies that are efficient, affordable, and reliable. Solar electric propulsion (SEP) has been proposed by NASA s Human Exploration Framework Team as an option to achieve human exploration missions to near Earth objects (NEOs) because of its favorable mass efficiency as compared to traditional chemical systems. This paper describes the unique challenges and technology hurdles associated with developing a large high-power SEP vehicle. A subsystem level breakdown of factors contributing to the feasibility of SEP as a platform for future exploration missions to NEOs is presented including overall mission feasibility, trip time variables, propellant management issues, solar array power generation, array structure issues, and other areas that warrant investment in additional technology or engineering development.

  9. Moonshot Science-Risks and Benefits.

    PubMed

    Casadevall, Arturo; Fang, Ferric C

    2016-08-30

    Ever since the successful Apollo 11 Moon landing in 1969, a "moonshot" has come to signify a bold effort to achieve a seemingly impossible task. The Obama administration recently called for a moonshot to cure cancer, an initiative that has elicited mixed responses from researchers who welcome additional funding but worry about raising expectations. We suggest that a successful moonshot requires a sufficient understanding of the basic science underlying a problem in question so that efforts can be focused on engineering a solution. Current gaps in our basic knowledge of cancer biology make the cancer moonshot a uniquely challenging endeavor. Nevertheless, history has shown that intensive research efforts have frequently yielded conceptual and technological breakthroughs with unanticipated benefits for society. We expect that this effort will be no different. Copyright © 2016 Casadevall and Fang.

  10. Army Net Zero: Energy Roadmap and Program Summary, Fiscal Year 2013 (Brochure)

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

    Not Available

    The U.S. Army (Army) partnered with the National Renewable Energy Laboratory (NREL) and the U.S. Army Corps of Engineers to assess opportunities for increasing energy security through improved energy efficiency and optimized renewable energy strategies at nine installations across the Army's portfolio. Referred to as Net Zero Energy Installations (NZEIs), these projects demonstrate and validate energy efficiency and renewable energy technologies with approaches that can be replicated across DOD and other Federal agencies, setting the stage for broad market adoption. This report summarizes the results of the energy project roadmaps developed by NREL, shows the progress each installation could makemore » in achieving Net Zero Energy by 2020, and presents lessons learned and unique challenges from each installation.« less

  11. Land surface temperature measurements from EOS MODIS data

    NASA Technical Reports Server (NTRS)

    Wan, Zhengming

    1993-01-01

    The task objectives of this reporting phase included: (1) completing the draft of the LST Algorithms Theoretical Basic Document by July 30, 1993; (2) making a detailed characterization of the thermal infrared measurement system including spectrometer, blackbody, and radiation sources; (3) making TIR spectral measurements of water and snow-cover surfaces with the MIDAC M2401 spectrometer; and (4) making conceptual and engineering design of an accessory system for spectrometric measurements at variable angles. These objectives are based on the requirements by the MODIS Science Team and the unique challenge in the development of MODIS LST algorithms: to acquire accurate spectral emissivity data of land covers in the near-term and to make ground validations of the LST product in the long-term with a TIR measurement system.

  12. Two main and a new type rare earth elements in Mg alloys: A review

    NASA Astrophysics Data System (ADS)

    Kong, Linghang

    2017-09-01

    Magnesium (Mg) alloys stand for the lightest structure engineering materials. Moreover, the strengthening of Mg alloys in ductility, toughness and corrosion predominates their wide applications. With adding rare earth elements in Mg, the mechanical properties will be improved remarkably, especially their plasticity and strength. A brief overview of the addition of rare earth elements for Mg alloys is shown. The basic mechanisms of strengthening Mg alloys with rare earth elements are reviewed, including the solid solution strengthening, grain refinement and long period stacking ordered (LPSO) phase. Furthermore, the available rare earth elements are summarized by type, chemical or physical effects and other unique properties. Finally, some challenge problems that the research is facing and future expectations of ra-re-earth Mg alloys are stated and discussed.

  13. The Advanced Technology Solar Telescope mount assembly

    NASA Astrophysics Data System (ADS)

    Warner, Mark; Cho, Myung; Goodrich, Bret; Hansen, Eric; Hubbard, Rob; Lee, Joon Pyo; Wagner, Jeremy

    2006-06-01

    When constructed on the summit of Haleakala on the island of Maui, Hawaii, the Advanced Technology Solar Telescope (ATST) will be the world's largest solar telescope. The ATST is a unique design that utilizes a state-of-the-art off-axis Gregorian optical layout with five reflecting mirrors delivering light to a Nasmyth instrument rotator, and nine reflecting mirrors delivering light to an instrument suite located on a large diameter rotating coude lab. The design of the telescope mount structure, which supports and positions the mirrors and scientific instruments, has presented noteworthy challenges to the ATST engineering staff. Several novel design solutions, as well as adaptations of existing telescope technologies to the ATST application, are presented in this paper. Also shown are plans for the control system and drives of the structure.

  14. CRBRP modular steam generator tube-to-tubesheet and shell-closure welding

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

    Viri, D.P.

    1982-01-01

    The original Modular Steam Generator (MSG), whiand inh was designed, built, and tested by the Energy Systems Group (ESG) of Rockwell International, was a departure from conventional boilers or heat exchangers. The design was a hockeystick concept - the upper section of the generator is curved 90/sup 0/. Factors affecting operating parameters were considered and incorporated in the original MSG design. The MSG was fully instrumented and functionally tested at the Energy Technology Engineering Center at Rockwell. The MSG steamed continuously for over 4000 h, and at the conclusion of the 9000-h test cycle, it was systematically dismantled and examinedmore » for wear to critical components. This paper explains the solutions to several manufacturing challenges presented by the unique design of the MSG.« less

  15. Smart Fluid Systems: The Advent of Autonomous Liquid Robotics

    PubMed Central

    2017-01-01

    Organic, inorganic or hybrid devices in the liquid state, kept in a fixed volume by surface tension or by a confining membrane that protects them from a harsh environment, could be used as biologically inspired autonomous robotic systems with unique capabilities. They could change shape according to a specific exogenous command or by means of a fully integrated adaptive system, and provide an innovative solution for many future applications, such as space exploration in extreme or otherwise challenging environments, post‐disaster search and rescue in ground applications, compliant wearable devices, and even in the medical field for in vivo applications. This perspective provides an initial assessment of existing capabilities that could be leveraged to pursue the topic of “Smart Fluid Systems” or “Liquid Engineered Systems”. PMID:28725530

  16. Flexible ferroelectric organic crystals

    DOE PAGES

    Owczarek, Magdalena; Hujsak, Karl A.; Ferris, Daniel P.; ...

    2016-10-13

    Flexible organic materials possessing useful electrical properties, such as ferroelectricity, are of crucial importance in the engineering of electronic devices. But, until now, only ferroelectric polymers have intrinsically met this flexibility requirement, leaving small-molecule organic ferroelectrics with room for improvement. Since both flexibility and ferroelectricity are rare properties on their own, combining them in one crystalline organic material is challenging. We report that trisubstituted haloimidazoles not only display ferroelectricity and piezoelectricity-the properties that originate from their non-centrosymmetric crystal lattice-but also lend their crystalline mechanical properties to fine-tuning in a controllable manner by disrupting the weak halogen bonds between the molecules.more » This element of control makes it possible to deliver another unique and highly desirable property, namely crystal flexibility. Moreover, the electrical properties are maintained in the flexible crystals.« less

  17. Superparamagnetic iron oxide nanoparticles: promises for diagnosis and treatment of cancer

    PubMed Central

    Laurent, Sophie; Mahmoudi, Morteza

    2011-01-01

    During the last decade, significant scientific research efforts have led to a significant growth in understanding of cancer at the genetic, molecular, and cellular levels providing great opportunities for diagnosis and treatment of cancer diseases. The hopes for fast cancer diagnosis and treatment were significantly increased by the entrance of nanoparticles to the medical sciences. Nanoparticles are attractive due to their unique opportunities together with negligible side effects not only in cancer therapy but also in the treatment of other ailments. Among all types of nanoparticles, surface-engineered superparamagnetic iron oxide nanoparticles (SPIONs) have been attracted a great attention for cancer therapy applications. This review covers the recent advances in the development of SPIONs together with their opportunities and challenges, as theranosis agents, in cancer treatment. PMID:22199999

  18. Integration of Multifidelity Multidisciplinary Computer Codes for Design and Analysis of Supersonic Aircraft

    NASA Technical Reports Server (NTRS)

    Geiselhart, Karl A.; Ozoroski, Lori P.; Fenbert, James W.; Shields, Elwood W.; Li, Wu

    2011-01-01

    This paper documents the development of a conceptual level integrated process for design and analysis of efficient and environmentally acceptable supersonic aircraft. To overcome the technical challenges to achieve this goal, a conceptual design capability which provides users with the ability to examine the integrated solution between all disciplines and facilitates the application of multidiscipline design, analysis, and optimization on a scale greater than previously achieved, is needed. The described capability is both an interactive design environment as well as a high powered optimization system with a unique blend of low, mixed and high-fidelity engineering tools combined together in the software integration framework, ModelCenter. The various modules are described and capabilities of the system are demonstrated. The current limitations and proposed future enhancements are also discussed.

  19. A unique research partnership investigating the fundamental principles of subsurface carbon dioxide behaviour and carbonate reservoirs

    NASA Astrophysics Data System (ADS)

    Macdonald, I.; Blunt, M. J.; Maitland, G. C.

    2017-12-01

    Carbonate reservoirs hold the majority of CO2 sequestration potential, however, they are also more complicated than sandstone reservoirs in terms of heterogeneity and potential reactivity impact on operations. There are both significant carbonate reservoir CO2 sinks and CO2 point sources around Qatar making carbon capture and storage a potential decarbonisation pathway. The Qatar Carbonates and Carbon Storage Research Centre (QCCSRC) was formed in 2009 to address the gaps in our current knowledge of both local carbonate reservoir platforms and how CO2 would behave post sequestration. Our work spans 35 graduated PhD students, 10 still studying, 29 post-doctoral researchers, 18 faculty members all aided by 5 support staff and more than 100 MSc and summer students from 30 different countries, the centre has published over 150 papers in over 40 different journals. Our research is based within the Department of Chemical Engineering and the Department of Earth Science and Engineering. Our team annually attends over 20 conferences world-wide to disseminate our findings and activity engage in outreach events (UNFCCC, science festivals, social media, science bars, school visits, etc.). QCCSRC is a research framework agreement over 10 years and valued at $70 million between Qatar Petroleum, Shell, the Qatar Science and Technology Park and Imperial College London bringing together each organisation's unique capabilities. This novel quadruple helix management structure is responsible for the largest single industrially funded research programme conducted at Imperial College London. Our research has focused on data to create and/or improve predictive models for CO2 storage in carbonate reservoirs. Our three broad thematic areas include: Rocks : Rock-fluid interactions : Fluid-fluid interactions and are supported by 5 laboratories. Overall this unique programme is an example of how to approach grand challenges in the energy-carbon dilemma through long-term and multidisciplinary cooperative research.

  20. Analytical and Numerical Solutions of Generalized Fokker-Planck Equations - Final Report

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

    Prinja, Anil K.

    The overall goal of this project was to develop advanced theoretical and numerical techniques to quantitatively describe the spreading of a collimated beam of charged particles in space, in angle, and in energy, as a result of small deflection, small energy transfer Coulomb collisions with the target nuclei and electrons. Such beams arise in several applications of great interest in nuclear engineering, and include electron and ion radiotherapy, ion beam modification of materials, accelerator transmutation of waste, and accelerator production of tritium, to name some important candidates. These applications present unique and difficult modeling challenges, but from the outset aremore » amenable to the language of ''transport theory'', which is very familiar to nuclear engineers and considerably less-so to physicists and material scientists. Thus, our approach has been to adopt a fundamental description based on transport equations, but the forward peakedness associated with charged particle interactions precludes a direct application of solution methods developed for neutral particle transport. Unique problem formulations and solution techniques are necessary to describe the transport and interaction of charged particles. In particular, we have developed the Generalized Fokker-Planck (GFP) approach to describe the angular and radial spreading of a collimated beam and a renormalized transport model to describe the energy-loss straggling of an initially monoenergetic distribution. Both analytic and numerical solutions have been investigated and in particular novel finite element numerical methods have been developed. In the first phase of the project, asymptotic methods were used to develop closed form solutions to the GFP equation for different orders of expansion, and was described in a previous progress report. In this final report we present a detailed description of (i) a novel energy straggling model based on a Fokker-Planck approximation but which is adapted for a multigroup transport setting, and (ii) two unique families of discontinuous finite element schemes, one linear and the other nonlinear.« less

  1. Engineering hematopoietic stem cells toward a functional cure of human immunodeficiency virus infection.

    PubMed

    Wang, Jianbin; Holmes, Michael C

    2016-11-01

    The battle with human immunodeficiency virus (HIV) has been ongoing for more than 30 years, and although progress has been made, there are still significant challenges remaining. A few unique features render HIV to be one of the toughest viruses to conquer in the modern medicine era, such as the ability to target the host immune system, persist by integrating into the host genome and adapt to a hostile environment such as a single anti-HIV medication by continuously evolving. The finding of combination anti-retroviral therapy (cART) about 2 decades ago has transformed the treatment options for HIV-infected patients and significantly improved patient outcomes. However, finding an HIV cure has proven to be extremely challenging with the only known exception being the so-called "Berlin patient," whose immune system was replaced by stem cell transplants from a donor missing one of HIV's key co-receptors (CCR5). The broad application of this approach is limited by the requirement of an HLA-matched donor who is also homozygous for the rare CCR5 delta32 deletion. On the other hand, the Berlin patient provided the proof of concept of a potential cure for HIV using HIV-resistant hematopoietic stem cells (HSCs), revitalizing the hope to find an HIV cure that is broadly applicable. Here we will review strategies and recent attempts to engineer HIV-resistant HSCs as a path to an HIV cure. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  2. Introductory Level Problems Illustrating Concepts in Pharmaceutical Engineering

    ERIC Educational Resources Information Center

    McIver, Keith; Whitaker, Kathryn; De Delva, Vladimir; Farrell, Stephanie; Savelski, Mariano J.; Slater, C. Stewart

    2012-01-01

    Textbook style problems including detailed solutions introducing pharmaceutical topics at the level of an introductory chemical engineering course have been created. The problems illustrate and teach subjects which students would learn if they were to pursue a career in pharmaceutical engineering, including the unique terminology of the field,…

  3. Surface Immobilization of Engineered Nanomaterials for in Situ Study of their Environmental Transformations and Fate

    EPA Science Inventory

    The transformation and environmental fate of engineered nanomaterials (ENMs) is the focus of intense research due to concerns about their potential impacts in the environment as a result of their uniquely engineered properties. Many approaches are being applied to investigate th...

  4. Creating Global Networks through an Online Engineering Graduate Programme

    ERIC Educational Resources Information Center

    Murray, M. H.

    2011-01-01

    Internationally, the railway industry is facing a severe shortage of engineers with high-level, relevant, professional and technical knowledge and abilities, in particular amongst engineers involved in the design, construction and maintenance of railway infrastructure. A unique graduate level programme has been created to meet that global need via…

  5. Introduction of Sustainability Concepts into Industrial Engineering Education: A Modular Approach

    ERIC Educational Resources Information Center

    Nazzal, Dima; Zabinski, Joseph; Hugar, Alexander; Reinhart, Debra; Karwowski, Waldemar; Madani, Kaveh

    2015-01-01

    Sustainability in operations, production, and consumption continues to gain relevance for engineers. This trend will accelerate as demand for goods and services grows, straining resources and requiring ingenuity to replace boundless supply in meeting the needs of a more crowded, more prosperous world. Industrial engineers are uniquely positioned…

  6. 40 CFR 1042.135 - Labeling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... EMISSIONS FROM NEW AND IN-USE MARINE COMPRESSION-IGNITION ENGINES AND VESSELS Emission Standards and Related Requirements § 1042.135 Labeling. (a) Assign each engine a unique identification number and permanently affix, engrave, or stamp it on the engine in a legible way. (b) At the time of manufacture, affix a permanent and...

  7. The scaling of performance and losses in miniature internal combustion engines

    NASA Astrophysics Data System (ADS)

    Menon, Shyam Kumar

    Miniature glow ignition internal combustion (IC) piston engines are an off--the--shelf technology that could dramatically increase the endurance of miniature electric power supplies and the range and endurance of small unmanned air vehicles provided their overall thermodynamic efficiencies can be increased to 15% or better. This thesis presents the first comprehensive analysis of small (<500 g) piston engine performance. A unique dynamometer system is developed that is capable of making reliable measurements of engine performance and losses in these small engines. Methodologies are also developed for measuring volumetric, heat transfer, exhaust, mechanical, and combustion losses. These instruments and techniques are used to investigate the performance of seven single-cylinder, two-stroke, glow fueled engines ranging in size from 15 to 450 g (0.16 to 7.5 cm3 displacement). Scaling rules for power output, overall efficiency, and normalized power are developed from the data. These will be useful to developers of micro-air vehicles and miniature power systems. The data show that the minimum length scale of a thermodynamically viable piston engine based on present technology is approximately 3 mm. Incomplete combustion is the most important challenge as it accounts for 60-70% of total energy losses. Combustion losses are followed in order of importance by heat transfer, sensible enthalpy, and friction. A net heat release analysis based on in-cylinder pressure measurements suggest that a two--stage combustion process occurs at low engine speeds and equivalence ratios close to 1. Different theories based on burning mode and reaction kinetics are proposed to explain the observed results. High speed imaging of the combustion chamber suggests that a turbulent premixed flame with its origin in the vicinity of the glow plug is the primary driver of combustion. Placing miniature IC engines on a turbulent combustion regime diagram shows that they operate in the 'flamelet in eddy' regime whereas conventional--scale engines operate mostly in the 'wrinkled laminar flame sheet' regime. Taken together, the results show that the combustion process is the key obstacle to realizing the potential of small IC engines. Overcoming this obstacle will require new diagnostic techniques, measurements, combustion models, and high temperature materials.

  8. Challenges of the English Teacher in the Engineering Faculty

    ERIC Educational Resources Information Center

    Astrid, Ramirez Valencia; Isabel, Borja-Alarcón; Alfonso, López-Vega

    2018-01-01

    Changes experienced in recent times focus their attention on new and multiple challenges that must be assumed by the English teacher, in the engineering context, which becomes a challenge against the demands by the current world from the English teacher in Colombia. This situation needs to be analyzed and studied. This article addresses the…

  9. Hard but Not Too Hard: Challenging Courses and Engineering Students

    ERIC Educational Resources Information Center

    Martin, Jason H.; Hands, Krista B.; Lancaster, Stephen M.; Trytten, Deborah A.; Murphy, Teri J.

    2008-01-01

    Some professors claim college students seek the easy way out and prefer classes that lack challenge. In a multidisciplinary and multi-institutional ethnographic research study of the attainment of gender parity in an engineering department, it emerged that student attitudes toward challenge did not support this perception. By far, the majority of…

  10. K-Channel: A Multifunctional Architecture for Dynamically Reconfigurable Sample Processing in Droplet Microfluidics.

    PubMed

    Doonan, Steven R; Bailey, Ryan C

    2017-04-04

    By rapidly creating libraries of thousands of unique, miniaturized reactors, droplet microfluidics provides a powerful method for automating high-throughput chemical analysis. In order to engineer in-droplet assays, microfluidic devices must add reagents into droplets, remove fluid from droplets, and perform other necessary operations, each typically provided by a unique, specialized geometry. Unfortunately, modifying device performance or changing operations usually requires re-engineering the device among these specialized geometries, a time-consuming and costly process when optimizing in-droplet assays. To address this challenge in implementing droplet chemistry, we have developed the "K-channel," which couples a cross-channel flow to the segmented droplet flow to enable a range of operations on passing droplets. K-channels perform reagent injection (0-100% of droplet volume), fluid extraction (0-50% of droplet volume), and droplet splitting (1:1-1:5 daughter droplet ratio). Instead of modifying device dimensions or channel configuration, adjusting external conditions, such as applied pressure and electric field, selects the K-channel process and tunes its magnitude. Finally, interfacing a device-embedded magnet allows selective capture of 96% of droplet-encapsulated superparamagnetic beads during 1:1 droplet splitting events at ∼400 Hz. Addition of a second K-channel for injection (after the droplet splitting K-channel) enables integrated washing of magnetic beads within rapidly moving droplets. Ultimately, the K-channel provides an exciting opportunity to perform many useful droplet operations across a range of magnitudes without requiring architectural modifications. Therefore, we envision the K-channel as a versatile, easy to use microfluidic component enabling diverse, in-droplet (bio)chemical manipulations.

  11. Oregon Sustainability Center: Weighing Approaches to Net Zero

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

    Regnier, Cindy; Robinson, Alastair; Settlemyre, Kevin

    2013-10-01

    The Oregon Sustainability Center (OSC) was to represent a unique public/private partnership between the city of Portland, Oregon, state government, higher education, non-profit organizations, and the business community. A unique group of stakeholders partnered with the U.S. Department of Energy (DOE) technical expert team (TET) to collaboratively identify, analyze, and evaluate solutions to enable the OSC to become a high-performance sustainability landmark in downtown Portland. The goal was to build a new, low-energy mixed-use urban high-rise that consumes at least 50 percent less energy than requirements set by Energy Standard 90.1-2007 of the American Society of Heating, Refrigerating, and Air-Conditioningmore » Engineers (ASHRAE), the American National Standards Institute (ANSI), and the Illuminating Engineering Society of America (IESNA) as part of DOE’s Commercial Building Partnerships (CBP) program.1 In addition, the building design was to incorporate renewable energy sources that would account for the remaining energy consumption, resulting in a net zero building. The challenge for the CBP DOE technical team was to evaluate factors of risk and components of resiliency in the current net zero energy design and analyze that design to see if the same high performance could be achieved by alternative measures at lower costs. In addition, the team was to use a “lens of scalability” to assess whether or not the strategies could be applied to more projects. However, a key component of the required project funding did not pass, and therefore this innovative building design was discontinued while it was in the design development stage.« less

  12. A smart rock

    NASA Astrophysics Data System (ADS)

    Pressel, Phil

    2014-12-01

    This project was to design and build a protective weapon for a group of associations that believed in aliens and UFO's. They collected enough contributions from societies and individuals to be able to sponsor and totally fund the design, fabrication and testing of this equipment. The location of this facility is classified. It also eventually was redesigned by the Quartus Engineering Company for use at a major amusement park as a "shoot at targets facility." The challenge of this project was to design a "smart rock," namely an infrared bullet (the size of a gallon can of paint) that could be shot from the ground to intercept a UFO or any incoming suspicious item heading towards the earth. Some of the challenges to design this weapon were to feed cryogenic helium at 5 degrees Kelvin from an inair environment through a unique rotary coupling and air-vacuum seal while spinning the bullet at 1500 rpm and maintain its dynamic stability (wobble) about its spin axis to less than 10 micro-radians (2 arc seconds) while it operated in a vacuum. Precision optics monitored the dynamic motion of the "smart rock."

  13. Basic Visual Disciplines in Heritage Conservation: Outline of Selected Perspectives in Teaching and Learning

    NASA Astrophysics Data System (ADS)

    Lobovikov-Katz, A.

    2017-08-01

    Acknowledgement of the value of a basic freehand sketch by the information and communication community of researchers and developers brought about the advanced developments for the use of sketches as free input to complicated processes of computerized visualization, so as to make them more widely accessible. However, a sharp reduction and even exclusion of this and other basic visual disciplines from education in sciences, technology, engineering and architecture dramatically reduces the number of future users of such applications. The unique needs of conservation of cultural heritage pose specific challenges as well as encourage the formulation of innovative development tasks in related areas of information and communication technologies (ICT). This paper claims that the introduction of basic visual disciplines to both communities is essential to the effectiveness of integration of heritage conservation needs and the advanced ICT development of conservation value, and beyond. It provides an insight into the challenges and advantages of introducing these subjects in a relevant educational context, presents some examples of their teaching and learning in the modern environment, including e-learning, and sketches perspectives to their application.

  14. SVAS3: Strain Vector Aided Sensorization of Soft Structures.

    PubMed

    Culha, Utku; Nurzaman, Surya G; Clemens, Frank; Iida, Fumiya

    2014-07-17

    Soft material structures exhibit high deformability and conformability which can be useful for many engineering applications such as robots adapting to unstructured and dynamic environments. However, the fact that they have almost infinite degrees of freedom challenges conventional sensory systems and sensorization approaches due to the difficulties in adapting to soft structure deformations. In this paper, we address this challenge by proposing a novel method which designs flexible sensor morphologies to sense soft material deformations by using a functional material called conductive thermoplastic elastomer (CTPE). This model-based design method, called Strain Vector Aided Sensorization of Soft Structures (SVAS3), provides a simulation platform which analyzes soft body deformations and automatically finds suitable locations for CTPE-based strain gauge sensors to gather strain information which best characterizes the deformation. Our chosen sensor material CTPE exhibits a set of unique behaviors in terms of strain length electrical conductivity, elasticity, and shape adaptability, allowing us to flexibly design sensor morphology that can best capture strain distributions in a given soft structure. We evaluate the performance of our approach by both simulated and real-world experiments and discuss the potential and limitations.

  15. Regenerative medicine, resource and regulation: lessons learned from the remedi project.

    PubMed

    Ginty, Patrick J; Rayment, Erin A; Hourd, Paul; Williams, David J

    2011-03-01

    The successful commercialization of regenerative medicine products provides a unique challenge to the manufacturer owing to a lack of suitable investment/business models and a constantly evolving regulatory framework. The resultant slow translation of scientific discovery into safe and clinically efficacious therapies is preventing many potential products from reaching the market. This is despite of the need for new therapies that may reduce the burden on the world's healthcare systems and address the desperate need for replacement tissues and organs. The collaborative Engineering and Physical Sciences Research Council (EPSRC)-funded remedi project was devised to take a holistic but manufacturing-led approach to the challenge of translational regenerative medicine in the UK. Through strategic collaborations and discussions with industry and other academic partners, many of the positive and negative issues surrounding business and regulatory success have been documented to provide a remedi-led perspective on the management of risk in business and the elucidation of the regulatory pathways, and how the two are inherently linked. This article represents the findings from these discussions with key stakeholders and the research into best business and regulatory practices.

  16. Bioinspired Tuning of Hydrogel Permeability-Rigidity Dependency for 3D Cell Culture

    NASA Astrophysics Data System (ADS)

    Lee, Min Kyung; Rich, Max H.; Baek, Kwanghyun; Lee, Jonghwi; Kong, Hyunjoon

    2015-03-01

    Hydrogels are being extensively used for three-dimensional immobilization and culture of cells in fundamental biological studies, biochemical processes, and clinical treatments. However, it is still a challenge to support viability and regulate phenotypic activities of cells in a structurally stable gel, because the gel becomes less permeable with increasing rigidity. To resolve this challenge, this study demonstrates a unique method to enhance the permeability of a cell-laden hydrogel while avoiding a significant change in rigidity of the gel. Inspired by the grooved skin textures of marine organisms, a hydrogel is assembled to present computationally optimized micro-sized grooves on the surface. Separately, a gel is engineered to preset aligned microchannels similar to a plant's vascular bundles through a uniaxial freeze-drying process. The resulting gel displays significantly increased water diffusivity with reduced changes of gel stiffness, exclusively when the microgrooves and microchannels are aligned together. No significant enhancement of rehydration is achieved when the microgrooves and microchannels are not aligned. Such material design greatly enhances viability and neural differentiation of stem cells and 3D neural network formation within the gel.

  17. Robust and Opportunistic Autonomous Science for a Potential Titan Aerobot

    NASA Technical Reports Server (NTRS)

    Gaines, Daniel M.; Estlin, Tara; Schaffer, Steve; Castano, Rebecca; Elfes, Alberto

    2010-01-01

    We are developing onboard planning and execution technologies to provide robust and opportunistic mission operations for a potential Titan aerobot. Aerobot have the potential for collecting a vast amount of high priority science data. However, to be effective, an aerobot must address several challenges including communication constraints, extended periods without contact with Earth, uncertain and changing environmental conditions, maneuverability constraints and potentially short-lived science opportunities. We are developing the AerOASIS system to develop and test technology to support autonomous science operations for a potential Titan Aerobot. The planning and execution component of AerOASIS is able to generate mission operations plans that achieve science and engineering objectives while respecting mission and resource constraints as well as adapting the plan to respond to new science opportunities. Our technology leverages prior work on the OASIS system for autonomous rover exploration. In this paper we describe how the OASIS planning component was adapted to address the unique challenges of a Titan Aerobot and we describe a field demonstration of the system with the JPL prototype aerobot.

  18. Overcoming the limited availability of human milk oligosaccharides: challenges and opportunities for research and application.

    PubMed

    Bode, Lars; Contractor, Nikhat; Barile, Daniela; Pohl, Nicola; Prudden, Anthony R; Boons, Geert-Jan; Jin, Yong-Su; Jennewein, Stefan

    2016-10-01

    Human milk oligosaccharides (HMOs) are complex sugars highly abundant in human milk but currently not present in infant formula. Rapidly accumulating evidence from in vitro and in vivo studies, combined with epidemiological associations and correlations, suggests that HMOs benefit infants through multiple mechanisms and in a variety of clinical contexts. Until recently, however, research on HMOs has been limited by an insufficient availability of HMOs. Most HMOs are found uniquely in human milk, and thus far it has been prohibitively tedious and expensive to isolate and synthesize them. This article reviews new strategies to overcome this lack of availability by generating HMOs through chemoenzymatic synthesis, microbial metabolic engineering, and isolation from human donor milk or dairy streams. Each approach has its advantages and comes with its own challenges, but combining the different methods and acknowledging their limitations creates new opportunities for research and application with the goal of improving maternal and infant health. © The Author(s) 2016. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  19. TOPICAL REVIEW: Prosthetic interfaces with the visual system: biological issues

    NASA Astrophysics Data System (ADS)

    Cohen, Ethan D.

    2007-06-01

    The design of effective visual prostheses for the blind represents a challenge for biomedical engineers and neuroscientists. Significant progress has been made in the miniaturization and processing power of prosthesis electronics; however development lags in the design and construction of effective machine brain interfaces with visual system neurons. This review summarizes what has been learned about stimulating neurons in the human and primate retina, lateral geniculate nucleus and visual cortex. Each level of the visual system presents unique challenges for neural interface design. Blind patients with the retinal degenerative disease retinitis pigmentosa (RP) are a common population in clinical trials of visual prostheses. The visual performance abilities of normals and RP patients are compared. To generate pattern vision in blind patients, the visual prosthetic interface must effectively stimulate the retinotopically organized neurons in the central visual field to elicit patterned visual percepts. The development of more biologically compatible methods of stimulating visual system neurons is critical to the development of finer spatial percepts. Prosthesis electrode arrays need to adapt to different optimal stimulus locations, stimulus patterns, and patient disease states.

  20. Repurposing mainstream CNC machine tools for laser-based additive manufacturing

    NASA Astrophysics Data System (ADS)

    Jones, Jason B.

    2016-04-01

    The advent of laser technology has been a key enabler for industrial 3D printing, known as Additive Manufacturing (AM). Despite its commercial success and unique technical capabilities, laser-based AM systems are not yet able to produce parts with the same accuracy and surface finish as CNC machining. To enable the geometry and material freedoms afforded by AM, yet achieve the precision and productivity of CNC machining, hybrid combinations of these two processes have started to gain traction. To achieve the benefits of combined processing, laser technology has been integrated into mainstream CNC machines - effectively repurposing them as hybrid manufacturing platforms. This paper reviews how this engineering challenge has prompted beam delivery innovations to allow automated changeover between laser processing and machining, using standard CNC tool changers. Handling laser-processing heads using the tool changer also enables automated change over between different types of laser processing heads, further expanding the breadth of laser processing flexibility in a hybrid CNC. This paper highlights the development, challenges and future impact of hybrid CNCs on laser processing.

  1. Nanoparticle-Based Manipulation of Antigen-Presenting Cells for Cancer Immunotherapy.

    PubMed

    Fang, Ronnie H; Kroll, Ashley V; Zhang, Liangfang

    2015-11-04

    Immunotherapeutic approaches for treating cancer overall have been receiving a considerable amount of interest due to the recent approval of several clinical formulations. Among the different modalities, anticancer vaccination acts by training the body to endogenously generate a response against tumor cells. However, despite the large amount of work that has gone into the development of such vaccines, the near absence of clinically approved formulations highlights the many challenges facing those working in the field. The generation of potent endogenous anticancer responses poses unique challenges due to the similarity between cancer cells and normal, healthy cells. As researchers continue to tackle the limited efficacy of vaccine formulations, fresh and novel approaches are being sought after to address many of the underlying problems. Here the application of nanoparticle technology towards the development of anticancer vaccines is discussed. Specifically, there is a focus on the benefits of using such strategies to manipulate antigen presenting cells (APCs), which are essential to the vaccination process, and how nanoparticle-based platforms can be rationally engineered to elicit appropriate downstream immune responses. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Cyber-Informed Engineering

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

    Anderson, Robert S.; Benjamin, Jacob; Wright, Virginia L.

    A continuing challenge for engineers who utilize digital systems is to understand the impact of cyber-attacks across the entire product and program lifecycle. This is a challenge due to the evolving nature of cyber threats that may impact the design, development, deployment, and operational phases of all systems. Cyber Informed Engineering is the process by which engineers are made aware of both how to use their engineering knowledge to positively impact the cyber security in the processes by which they architect and design components and the services and security of the components themselves.

  3. The Radical Flank Effect and Cross-occupational Collaboration for Technology Development during a Power Shift

    PubMed Central

    Truelove, Emily; Kellogg, Katherine C.

    2016-01-01

    This 12-month ethnographic study of an early entrant into the U.S. car-sharing industry demonstrates that when an organization shifts its focus from developing radical new technology to incrementally improving this technology, the shift may spark an internal power struggle between the dominant engineering group and a challenger occupational group such as the marketing group. Analyzing 42 projects in two time periods that required collaboration between engineering and marketing during such a shift, we show how cross-occupational collaboration under these conditions can be facilitated by a radical flank threat, through which the bargaining power of moderates is strengthened by the presence of a more-radical group. In the face of a strong threat by radical members of a challenger occupational group, moderate members of the dominant engineering group may change their perceptions of their power to resist challengers’ demands and begin to distinguish between the goals of radical versus more-moderate challengers. To maintain as much power as possible and prevent the more-dramatic change in engineering occupational goals demanded by radical challengers, moderate engineers may build a coalition with moderate challengers and collaborate for incremental technology development. PMID:28424533

  4. ADDRESSING ENVIRONMENTAL ENGINEERING CHALLENGES WITH COMPUTATIONAL FLUID DYNAMICS

    EPA Science Inventory

    This paper discusses the status and application of Computational Fluid Dynamics )CFD) models to address environmental engineering challenges for more detailed understanding of air pollutant source emissions, atmospheric dispersion and resulting human exposure. CFD simulations ...

  5. Moving oncolytic viruses into the clinic: clinical-grade production, purification, and characterization of diverse oncolytic viruses.

    PubMed

    Ungerechts, Guy; Bossow, Sascha; Leuchs, Barbara; Holm, Per S; Rommelaere, Jean; Coffey, Matt; Coffin, Rob; Bell, John; Nettelbeck, Dirk M

    2016-01-01

    Oncolytic viruses (OVs) are unique anticancer agents based on their pleotropic modes of action, which include, besides viral tumor cell lysis, activation of antitumor immunity. A panel of diverse viruses, often genetically engineered, has advanced to clinical investigation, including phase 3 studies. This diversity of virotherapeutics not only offers interesting opportunities for the implementation of different therapeutic regimens but also poses challenges for clinical translation. Thus, manufacturing processes and regulatory approval paths need to be established for each OV individually. This review provides an overview of clinical-grade manufacturing procedures for OVs using six virus families as examples, and key challenges are discussed individually. For example, different virus features with respect to particle size, presence/absence of an envelope, and host species imply specific requirements for measures to ensure sterility, for handling, and for determination of appropriate animal models for toxicity testing, respectively. On the other hand, optimization of serum-free culture conditions, increasing virus yields, development of scalable purification strategies, and formulations guaranteeing long-term stability are challenges common to several if not all OVs. In light of the recent marketing approval of the first OV in the Western world, strategies for further upscaling OV manufacturing and optimizing product characterization will receive increasing attention.

  6. Challenges to Laser-Based Imaging Techniques in Gas Turbine Combustor Systems for Aerospace Applications

    NASA Technical Reports Server (NTRS)

    Locke, Randy J.; Anderson, Robert C.; Zaller, Michelle M.; Hicks, Yolanda R.

    1998-01-01

    Increasingly severe constraints on emissions, noise and fuel efficiency must be met by the next generation of commercial aircraft powerplants. At NASA Lewis Research Center (LeRC) a cooperative research effort with industry is underway to design and test combustors that will meet these requirements. To accomplish these tasks, it is necessary to gain both a detailed understanding of the combustion processes and a precise knowledge of combustor and combustor sub-component performance at close to actual conditions. To that end, researchers at LeRC are engaged in a comprehensive diagnostic investigation of high pressure reacting flowfields that duplicate conditions expected within the actual engine combustors. Unique, optically accessible flame-tubes and sector rig combustors, designed especially for these tests. afford the opportunity to probe these flowfields with the most advanced, laser-based optical diagnostic techniques. However, these same techniques, tested and proven on comparatively simple bench-top gaseous flame burners, encounter numerous restrictions and challenges when applied in these facilities. These include high pressures and temperatures, large flow rates, liquid fuels, remote testing, and carbon or other material deposits on combustor windows. Results are shown that document the success and versatility of these nonintrusive optical diagnostics despite the challenges to their implementation in realistic systems.

  7. Moving oncolytic viruses into the clinic: clinical-grade production, purification, and characterization of diverse oncolytic viruses

    PubMed Central

    Ungerechts, Guy; Bossow, Sascha; Leuchs, Barbara; Holm, Per S; Rommelaere, Jean; Coffey, Matt; Coffin, Rob; Bell, John; Nettelbeck, Dirk M

    2016-01-01

    Oncolytic viruses (OVs) are unique anticancer agents based on their pleotropic modes of action, which include, besides viral tumor cell lysis, activation of antitumor immunity. A panel of diverse viruses, often genetically engineered, has advanced to clinical investigation, including phase 3 studies. This diversity of virotherapeutics not only offers interesting opportunities for the implementation of different therapeutic regimens but also poses challenges for clinical translation. Thus, manufacturing processes and regulatory approval paths need to be established for each OV individually. This review provides an overview of clinical-grade manufacturing procedures for OVs using six virus families as examples, and key challenges are discussed individually. For example, different virus features with respect to particle size, presence/absence of an envelope, and host species imply specific requirements for measures to ensure sterility, for handling, and for determination of appropriate animal models for toxicity testing, respectively. On the other hand, optimization of serum-free culture conditions, increasing virus yields, development of scalable purification strategies, and formulations guaranteeing long-term stability are challenges common to several if not all OVs. In light of the recent marketing approval of the first OV in the Western world, strategies for further upscaling OV manufacturing and optimizing product characterization will receive increasing attention. PMID:27088104

  8. Synthesis and Characterization of Block Copolymers with Unique Chemical Functionalities and Entropically-Hindering Moieties

    DTIC Science & Technology

    2017-08-14

    Synthesis and Characterization of Sulfonated Amine Block Copolymers for Energy Efficient Applications". Chemical Engineering Symposium, University of...Specialty Separations” Oral Presentation during the 2014 Chemical Engineering Department Symposium (Key Note Speaker), University of Puerto Rico, Mayaguez...Leadership Award in the College of Engineering of the University of Puerto Rico, May, 2015. 3. Distinguished Professor of Chemical Engineering

  9. Ergonomic audit of a specially engineered sonic powered toothbrush with unique sensing and control technologies, the Sonicare Flexcare, and the Oral-B Smart Series 5000.

    PubMed

    Hunter, Gail; Burns, Laurie; Bone, Brian; Mintel, Thomas; Jimenez, Eduardo

    2012-01-01

    The presence of ergonomic features can impact the marketplace success of a new product. Metaphase Design Group, Inc., in partnership with the Colgate-Palmolive Company, conducted an ergonomic audit on three electric toothbrushes: a specially engineered sonic powered toothbrush with unique sensing and control technologies, the Sonicare FlexCare, and the Oral-B Smart Series 5000. The ergonomic audit was conducted by Metaphase Design Groups's ergonomic and usability experts. Two experts used the toothbrushes over a one-week period and assessed the performance of each brush against a set of ergonomic principles. The three toothbrushes have some solid ergonomic features. They each have adequate grip zones, provide grip security with elastomeric materials, and provide easy access to the on/off button. The most distinctive feature is the longitudinal shape of the handle of the specially engineered sonic powered toothbrush with unique sensing and control technologies. This handle angles downward at the top end and provides additional advantages through improved grip security and visibility. Yet all three toothbrushes have different opportunities for improvement. The Sonicare Flex Care toothbrush has a cluttered and complicated user interface that is difficult to read. The disadvantages of the Oral-B Smart Series 5000 toothbrush are related to its physical dimensions and audible feedback. The specially engineered sonic powered toothbrush with unique sensing afid control technologies is surprising to use with its changes in speeds, brush movements, and resulting changes in audible feedback.

  10. Challenges and opportunities in synthetic biology for chemical engineers

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

    Luo, YZ; Lee, JK; Zhao, HM

    Synthetic biology provides numerous great opportunities for chemical engineers in the development of new processes for large-scale production of biofuels, value-added chemicals, and protein therapeutics. However, challenges across all scales abound. In particular, the modularization and standardization of the components in a biological system, so-called biological parts, remain the biggest obstacle in synthetic biology. In this perspective, we will discuss the main challenges and opportunities in the rapidly growing synthetic biology field and the important roles that chemical engineers can play in its advancement. (C) 2012 Elsevier Ltd. All rights reserved.

  11. Challenges and opportunities in synthetic biology for chemical engineers

    PubMed Central

    Luo, Yunzi; Lee, Jung-Kul; Zhao, Huimin

    2012-01-01

    Synthetic biology provides numerous great opportunities for chemical engineers in the development of new processes for large-scale production of biofuels, value-added chemicals, and protein therapeutics. However, challenges across all scales abound. In particular, the modularization and standardization of the components in a biological system, so-called biological parts, remain the biggest obstacle in synthetic biology. In this perspective, we will discuss the main challenges and opportunities in the rapidly growing synthetic biology field and the important roles that chemical engineers can play in its advancement. PMID:24222925

  12. Challenges and opportunities in synthetic biology for chemical engineers.

    PubMed

    Luo, Yunzi; Lee, Jung-Kul; Zhao, Huimin

    2013-11-15

    Synthetic biology provides numerous great opportunities for chemical engineers in the development of new processes for large-scale production of biofuels, value-added chemicals, and protein therapeutics. However, challenges across all scales abound. In particular, the modularization and standardization of the components in a biological system, so-called biological parts, remain the biggest obstacle in synthetic biology. In this perspective, we will discuss the main challenges and opportunities in the rapidly growing synthetic biology field and the important roles that chemical engineers can play in its advancement.

  13. Fueling Chemical Engineering Concepts with Biodiesel Production: A Professional Development Experience for High School Pre-Service Teachers

    ERIC Educational Resources Information Center

    Gupta, Anju

    2015-01-01

    This one-day workshop for pre-service teachers was aimed at implementing a uniquely designed and ready-to-implement chemical engineering curriculum in high school coursework. This educational and professional development opportunity introduced: 1) chemical engineering curriculum and career opportunities, 2) basic industrial processes and flow…

  14. The Kamusi Project Edit Engine: A Tool for Collaborative Lexicography.

    ERIC Educational Resources Information Center

    Benjamin, Martin; Biersteker, Ann

    2001-01-01

    Discusses the design and implementation of the Kamusi Project Edit Engine, a Web-based software system uniquely suited to the needs of Swahili collaborative lexicography. Describes the edit engine, including organization of the lexicon and the mechanics by which participants use the system, discusses philosophical issues confronted in the design,…

  15. Teaching Engineering at the K-12 Level: Two Perspectives

    ERIC Educational Resources Information Center

    Smith, Kenneth L.; Burghardt, David

    2007-01-01

    In this article, the authors share their own perspectives regarding engineering education at the K-12 level. Smith believes that there must be a more direct infusion of appropriate mathematics and science with the unique technological content (tools, machines, materials, processes) for an effective engineering education program to exist. He thinks…

  16. Design and Implementation of Multi-Campus, Modular Master Classes in Biochemical Engineering

    ERIC Educational Resources Information Center

    Wuyts, Niek; Bruneel, Dorine; Meyers, Myriam; Van Hoof, Etienne; De Vos, Leander; Langie, Greet; Rediers, Hans

    2015-01-01

    The Master of Science in engineering technology: biochemical engineering is organised in KU Leuven at four geographically dispersed campuses. To sustain the Master's programmes at all campuses, it is clear that a unique education profile at each campus is crucial. In addition, a rationalisation is required by increased cooperation, increased…

  17. DRUMS: a human disease related unique gene mutation search engine.

    PubMed

    Li, Zuofeng; Liu, Xingnan; Wen, Jingran; Xu, Ye; Zhao, Xin; Li, Xuan; Liu, Lei; Zhang, Xiaoyan

    2011-10-01

    With the completion of the human genome project and the development of new methods for gene variant detection, the integration of mutation data and its phenotypic consequences has become more important than ever. Among all available resources, locus-specific databases (LSDBs) curate one or more specific genes' mutation data along with high-quality phenotypes. Although some genotype-phenotype data from LSDB have been integrated into central databases little effort has been made to integrate all these data by a search engine approach. In this work, we have developed disease related unique gene mutation search engine (DRUMS), a search engine for human disease related unique gene mutation as a convenient tool for biologists or physicians to retrieve gene variant and related phenotype information. Gene variant and phenotype information were stored in a gene-centred relational database. Moreover, the relationships between mutations and diseases were indexed by the uniform resource identifier from LSDB, or another central database. By querying DRUMS, users can access the most popular mutation databases under one interface. DRUMS could be treated as a domain specific search engine. By using web crawling, indexing, and searching technologies, it provides a competitively efficient interface for searching and retrieving mutation data and their relationships to diseases. The present system is freely accessible at http://www.scbit.org/glif/new/drums/index.html. © 2011 Wiley-Liss, Inc.

  18. The Transformative Potential of Engaging in Science Inquiry-Based Challenges: The ATSE Wonder of Science Challenge

    ERIC Educational Resources Information Center

    Tomas, Louisa; Jackson, Cliff; Carlisle, Karen

    2014-01-01

    In 2012, the Australian Academy of Technological Sciences and Engineering (ATSE) piloted the "Wonder of Science Challenge" with a view to enhance school students' interest in Science, Technology, Engineering and Mathematics (STEM). Students in 15 schools across northern Queensland were provided with an inquiry-based research problem and…

  19. Technology Transfer Challenges for High-Assurance Software Engineering Tools

    NASA Technical Reports Server (NTRS)

    Koga, Dennis (Technical Monitor); Penix, John; Markosian, Lawrence Z.

    2003-01-01

    In this paper, we describe our experience with the challenges thar we are currently facing in our effort to develop advanced software verification and validation tools. We categorize these challenges into several areas: cost benefits modeling, tool usability, customer application domain, and organizational issues. We provide examples of challenges in each area and identrfj, open research issues in areas which limit our ability to transfer high-assurance software engineering tools into practice.

  20. Challenges and Promises of Overcoming Epistemological and Methodological Partiality: Advancing Engineering Education through Acceptance of Diverse Ways of Knowing

    ERIC Educational Resources Information Center

    Douglas, Elliot P.; Koro-Ljungberg, Mirka; Borrego, Maura

    2010-01-01

    The purpose of this paper is to explore some challenges and promises when the epistemological diversity embedded in qualitative research traditions is introduced to research communities with one dominant research paradigm, such as engineering education. Literature is used from other fields and empirical data are used from engineering education,…

  1. Decellularized material as scaffolds for tissue engineering studies in long gap esophageal atresia.

    PubMed

    Lee, Esmond; Milan, Anna; Urbani, Luca; De Coppi, Paolo; Lowdell, Mark W

    2017-05-01

    Esophageal atresia refers to an anomaly in foetal development in which the esophagus terminates in a blind end. Whilst surgical correction is achievable in most patients, when a long gap is present it still represents a major challenge associated with higher morbidity and mortality. In this context, tissue engineering could represent a successful alternative to restore oesophageal function and structure. Naturally derived biomaterials made of decellularized tissues retain native extracellular matrix architecture and composition, providing a suitable bed for the anchorage and growth of relevant cell types. Areas covered: This review outlines the various strategies and challenges in esophageal tissue engineering, highlighting the evolution of ideas in the development of decellularized scaffolds for clinical use. It explores the interplay between clinical needs, ethical dilemmas, and manufacturing challenges in the development of a tissue engineered decellularized scaffold for oesophageal atresia. Expert opinion: Current progress on oesophageal tissue engineering has enabled effective repair of patch defects, whilst the development of a full circumferential construct remains a challenge. Despite the different approaches available and the improvements achieved, a gold standard for fully functional tissue engineered oesophageal constructs has not been defined yet.

  2. Representation and misrepresentation: Tufte and the Morton Thiokol engineers on the Challenger.

    PubMed

    Robison, Wade; Boisjoly, Roger; Hoeker, David; Young, Stefan

    2002-01-01

    This paper examines the role of the Morton Thiokol engineers in the decisions surrounding the launch of the Challenger, particularly with reference to an analysis of this event by Edward Tufte. The engineers at Morton Thiokol recommended against the launch of Challenger because the projected launch temperature between 26 degrees F to 29 degrees F was far outside their field database of successful launches. The engineers had asked for, but not received, data necessary to determine the cause of massive blow-by on the launch the previous January, and they had informed their managers and NASA that continuing flights could be catastrophic if the cause of the problems with the launches was not discovered. The authors conclude that the engineers thus did what they were ethically as well as professionally obligated to do.

  3. Criteria for preservation and adaptive use of historic highway structures.

    DOT National Transportation Integrated Search

    1978-01-01

    Metal truss bridges are uniquely indigenous products of American engineering and construction technology, and in recent years their historic significance has been increasingly recognized along with that of other early engineering structures. Some tru...

  4. Responsible authorship in engineering fields: an overview of current ethical challenges.

    PubMed

    Borenstein, Jason

    2011-06-01

    The primary aim of this article is to identify ethical challenges relating to authorship in engineering fields. Professional organizations and journals do provide crucial guidance in this realm, but this cannot replace the need for frequent and diligent discussions in engineering research communities about what constitutes appropriate authorship practice. Engineering researchers should seek to identify and address issues such as who is entitled to be an author and whether publishing their research could potentially harm the public.

  5. Supporting information retrieval from electronic health records: A report of University of Michigan's nine-year experience in developing and using the Electronic Medical Record Search Engine (EMERSE).

    PubMed

    Hanauer, David A; Mei, Qiaozhu; Law, James; Khanna, Ritu; Zheng, Kai

    2015-06-01

    This paper describes the University of Michigan's nine-year experience in developing and using a full-text search engine designed to facilitate information retrieval (IR) from narrative documents stored in electronic health records (EHRs). The system, called the Electronic Medical Record Search Engine (EMERSE), functions similar to Google but is equipped with special functionalities for handling challenges unique to retrieving information from medical text. Key features that distinguish EMERSE from general-purpose search engines are discussed, with an emphasis on functions crucial to (1) improving medical IR performance and (2) assuring search quality and results consistency regardless of users' medical background, stage of training, or level of technical expertise. Since its initial deployment, EMERSE has been enthusiastically embraced by clinicians, administrators, and clinical and translational researchers. To date, the system has been used in supporting more than 750 research projects yielding 80 peer-reviewed publications. In several evaluation studies, EMERSE demonstrated very high levels of sensitivity and specificity in addition to greatly improved chart review efficiency. Increased availability of electronic data in healthcare does not automatically warrant increased availability of information. The success of EMERSE at our institution illustrates that free-text EHR search engines can be a valuable tool to help practitioners and researchers retrieve information from EHRs more effectively and efficiently, enabling critical tasks such as patient case synthesis and research data abstraction. EMERSE, available free of charge for academic use, represents a state-of-the-art medical IR tool with proven effectiveness and user acceptance. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  6. Tunable and label-free virus enrichment for ultrasensitive virus detection using carbon nanotube arrays

    PubMed Central

    Yeh, Yin-Ting; Tang, Yi; Sebastian, Aswathy; Dasgupta, Archi; Perea-Lopez, Nestor; Albert, Istvan; Lu, Huaguang; Terrones, Mauricio; Zheng, Si-Yang

    2016-01-01

    Viral infectious diseases can erupt unpredictably, spread rapidly, and ravage mass populations. Although established methods, such as polymerase chain reaction, virus isolation, and next-generation sequencing have been used to detect viruses, field samples with low virus count pose major challenges in virus surveillance and discovery. We report a unique carbon nanotube size-tunable enrichment microdevice (CNT-STEM) that efficiently enriches and concentrates viruses collected from field samples. The channel sidewall in the microdevice was made by growing arrays of vertically aligned nitrogen-doped multiwalled CNTs, where the intertubular distance between CNTs could be engineered in the range of 17 to 325 nm to accurately match the size of different viruses. The CNT-STEM significantly improves detection limits and virus isolation rates by at least 100 times. Using this device, we successfully identified an emerging avian influenza virus strain [A/duck/PA/02099/2012(H11N9)] and a novel virus strain (IBDV/turkey/PA/00924/14). Our unique method demonstrates the early detection of emerging viruses and the discovery of new viruses directly from field samples, thus creating a universal platform for effectively remediating viral infectious diseases. PMID:27730213

  7. Assessing public health job portals over the internet.

    PubMed

    Joshi, Ashish; Mirza, Attiqa; McFarlane, Kim; Amadi, Chioma

    2016-09-01

    The objective of our study was to search existing public health job websites over the internet and describe the challenges related to finding these job websites. An internet search was conducted using different search engines, including Google, Yahoo and Bing, with several keywords including: Public Health Jobs, Epidemiology Jobs, Biostatistics Jobs, Health Policy and Management Jobs, Community Health Jobs, Health Administration Jobs, Nutrition Jobs, Environmental and Occupational Health Science Jobs, GIS Jobs, and Public Health Informatics Jobs. We recorded the first 20 websites that appeared in the results of each keyword search, thus generating 600 URLs. Duplicate sites and non-functional sites were excluded from this search, allowing analysis of unique sites only. The initial search resulted in 600 websites of which there were 470 duplicates. More than half of the website categories were ".com" (54%; n = 323) followed by ".gov" (19%; n = 111) and ".edu" 15% (n = 90). Results of our findings showed 194 unique websites resulting from a search of 600 website links. More than half of them had actual public health or its related jobs (56%; n = 108). There is a need to establish standard occupational classification categories for the public health workforce. © Royal Society for Public Health 2016.

  8. Neurophotonics: optical methods to study and control the brain

    NASA Astrophysics Data System (ADS)

    Doronina-Amitonova, L. V.; Fedotov, I. V.; Fedotov, A. B.; Anokhin, K. V.; Zheltikov, A. M.

    2015-04-01

    Methods of optical physics offer unique opportunities for the investigation of brain and higher nervous activity. The integration of cutting-edge laser technologies and advanced neurobiology opens a new cross-disciplinary area of natural sciences - neurophotonics - focusing on the development of a vast arsenal of tools for functional brain diagnostics, stimulation of individual neurons and neural networks, and the molecular engineering of brain cells aimed at the diagnosis and therapy of neurodegenerative and psychic diseases. Optical fibers help to confront the most challenging problems in brain research, including the analysis of molecular-cellular mechanisms of the formation of memory and behavior. New generation optical fibers provide new solutions for the development of fundamentally new, unique tools for neurophotonics and laser neuroengineering - fiber-optic neuroendoscopes and neurointerfaces. These instruments broaden research horizons when investigating the most complex brain functions, enabling a long-term multiplex detection of fluorescent protein markers, as well as photostimulation of neuronal activity in deep brain areas in living, freely moving animals with an unprecedented spatial resolution and minimal invasiveness. This emerging technology opens new horizons for understanding learning and long-term memory through experiments with living, freely moving mammals. Here, we present a brief review of this rapidly growing field of research.

  9. A diagnostic signal selection scheme for planetary gearbox vibration monitoring under non-stationary operational conditions

    NASA Astrophysics Data System (ADS)

    Feng, Ke; Wang, KeSheng; Zhang, Mian; Ni, Qing; Zuo, Ming J.

    2017-03-01

    The planetary gearbox, due to its unique mechanical structures, is an important rotating machine for transmission systems. Its engineering applications are often in non-stationary operational conditions, such as helicopters, wind energy systems, etc. The unique physical structures and working conditions make the vibrations measured from planetary gearboxes exhibit a complex time-varying modulation and therefore yield complicated spectral structures. As a result, traditional signal processing methods, such as Fourier analysis, and the selection of characteristic fault frequencies for diagnosis face serious challenges. To overcome this drawback, this paper proposes a signal selection scheme for fault-emphasized diagnostics based upon two order tracking techniques. The basic procedures for the proposed scheme are as follows. (1) Computed order tracking is applied to reveal the order contents and identify the order(s) of interest. (2) Vold-Kalman filter order tracking is used to extract the order(s) of interest—these filtered order(s) constitute the so-called selected vibrations. (3) Time domain statistic indicators are applied to the selected vibrations for faulty information-emphasized diagnostics. The proposed scheme is explained and demonstrated in a signal simulation model and experimental studies and the method proves to be effective for planetary gearbox fault diagnosis.

  10. The Role of the Strutjet Engine in New Global and Space Markets

    NASA Technical Reports Server (NTRS)

    Siebenhaar, A.; Bulman, M. J.; Bonnar, D. K.

    1998-01-01

    The Strutjet, discussed in previous IAF papers, was originally introduced as an enabling propulsion concept for single stage to orbit applications. Recent design considerations indicate that this systems also provides benefits supportive of other commercial non-space applications. This paper describes the technical progress of the Strutjet since 1997 together with a rationale why Rocket Based Combined Cycle Engines in general, and the Strutjet in particular, lend themselves uniquely to systems having the ability to expand current space and open new global 'rapid delivery' markets. During this decade, Strutjet technology has been evaluated in over 1000 tests. Its design maturity has been continuously improved and desired features, like simple variable geometry and low drag flowpath resulting in high performance, have been verified. In addition, data is now available which allows the designer, who is challenged to maximize system operability and economic feasibility, to choose between hydrogen or hydrocarbon fuels for a variety of application. The ability exists now to apply this propulsion system to various vehicles with a multitude of missions. In this paper, storable hydrocarbon and gaseous hydrogen Strutjet RBCC test data as accomplished to date and as planned for the future is presented, and the degree of required technology maturity achieved so far is assessed. Two vehicles, using cryogenic propane fuel Strutjet engines, and specifically designed for rapid point-to-point cargo delivery between Pacific rim locations are introduced, discussed, and compared.

  11. Structural characterization of UHPC waffle bridge deck and connections.

    DOT National Transportation Integrated Search

    2014-07-01

    The AASHTO strategic plan in 2005 for bridge engineering identified extending the service life of bridges and accelerating bridge : construction as two of the grand challenges in bridge engineering. These challenges have the objective of producing sa...

  12. Testing Scientific Software: A Systematic Literature Review.

    PubMed

    Kanewala, Upulee; Bieman, James M

    2014-10-01

    Scientific software plays an important role in critical decision making, for example making weather predictions based on climate models, and computation of evidence for research publications. Recently, scientists have had to retract publications due to errors caused by software faults. Systematic testing can identify such faults in code. This study aims to identify specific challenges, proposed solutions, and unsolved problems faced when testing scientific software. We conducted a systematic literature survey to identify and analyze relevant literature. We identified 62 studies that provided relevant information about testing scientific software. We found that challenges faced when testing scientific software fall into two main categories: (1) testing challenges that occur due to characteristics of scientific software such as oracle problems and (2) testing challenges that occur due to cultural differences between scientists and the software engineering community such as viewing the code and the model that it implements as inseparable entities. In addition, we identified methods to potentially overcome these challenges and their limitations. Finally we describe unsolved challenges and how software engineering researchers and practitioners can help to overcome them. Scientific software presents special challenges for testing. Specifically, cultural differences between scientist developers and software engineers, along with the characteristics of the scientific software make testing more difficult. Existing techniques such as code clone detection can help to improve the testing process. Software engineers should consider special challenges posed by scientific software such as oracle problems when developing testing techniques.

  13. Design Challenges Encountered in a Propulsion-Controlled Aircraft Flight Test Program

    NASA Technical Reports Server (NTRS)

    Maine, Trindel; Burken, John; Burcham, Frank; Schaefer, Peter

    1994-01-01

    The NASA Dryden Flight Research Center conducted flight tests of a propulsion-controlled aircraft system on an F-15 airplane. This system was designed to explore the feasibility of providing safe emergency landing capability using only the engines to provide flight control in the event of a catastrophic loss of conventional flight controls. Control laws were designed to control the flightpath and bank angle using only commands to the throttles. Although the program was highly successful, this paper highlights some of the challenges associated with using engine thrust as a control effector. These challenges include slow engine response time, poorly modeled nonlinear engine dynamics, unmodeled inlet-airframe interactions, and difficulties with ground effect and gust rejection. Flight and simulation data illustrate these difficulties.

  14. Extensible Adaptable Simulation Systems: Supporting Multiple Fidelity Simulations in a Common Environment

    NASA Technical Reports Server (NTRS)

    McLaughlin, Brian J.; Barrett, Larry K.

    2012-01-01

    Common practice in the development of simulation systems is meeting all user requirements within a single instantiation. The Joint Polar Satellite System (JPSS) presents a unique challenge to establish a simulation environment that meets the needs of a diverse user community while also spanning a multi-mission environment over decades of operation. In response, the JPSS Flight Vehicle Test Suite (FVTS) is architected with an extensible infrastructure that supports the operation of multiple observatory simulations for a single mission and multiple mission within a common system perimeter. For the JPSS-1 satellite, multiple fidelity flight observatory simulations are necessary to support the distinct user communities consisting of the Common Ground System development team, the Common Ground System Integration & Test team, and the Mission Rehearsal Team/Mission Operations Team. These key requirements present several challenges to FVTS development. First, the FVTS must ensure all critical user requirements are satisfied by at least one fidelity instance of the observatory simulation. Second, the FVTS must allow for tailoring of the system instances to function in diverse operational environments from the High-security operations environment at NOAA Satellite Operations Facility (NSOF) to the ground system factory floor. Finally, the FVTS must provide the ability to execute sustaining engineering activities on a subset of the system without impacting system availability to parallel users. The FVTS approach of allowing for multiple fidelity copies of observatory simulations represents a unique concept in simulator capability development and corresponds to the JPSS Ground System goals of establishing a capability that is flexible, extensible, and adaptable.

  15. Mars Reconnaissance Orbiter Mission: Systems Engineering Challenges on the Mars Reconnaissance Orbiter Mission

    NASA Technical Reports Server (NTRS)

    Havens, Glen G.

    2007-01-01

    MRO project is a system of systems requiring system engineering team to architect, design, integrate, test, and operate these systems at each level of the project. The challenge of system engineering mission objectives into a single mission architecture that can be integrated tested, launched, and operated. Systems engineering must translate high-level requirements into integrated mission design. Systems engineering challenges were overcome utilizing a combination by creative designs built into MRO's flight and ground systems: a) Design of sophisticated spacecraft targeting and data management capabilities b) Establishment of a strong operations team organization; c) Implementation of robust operational processes; and d) Development of strategic ground tools. The MRO system has met the challenge of its driving requirements: a) MRO began its two-year primary science phase on November 7, 2006, and by July 2007, met it minimum requirement to collect 15 Tbits of data after only eight months of operations. Currently we have collected 22 Tbits. b) Based on current performance, mission data return could return 70 Tbits of data by the end of the primary science phase in 2008.

  16. Overcoming Present-Day Powerplant Limitations Via Unconventional Engine Configurations

    NASA Technical Reports Server (NTRS)

    Meitner, Peter L.

    2006-01-01

    The Army Research Laboratory s Vehicle Technology Directorate is sponsoring the prototype development of three unconventional engine concepts - two intermittent combustion (IC) engines and one turbine engine (via SBIR (Small Business Innovative Research) contracts). The IC concepts are the Nutating Engine and the Bonner Engine, and the turbine concept is the POWER Engine. Each of the three engines offers unique and greatly improved capabilities (which cannot be achieved by present-day powerplants), while offering significant reductions in size and weight. This paper presents brief descriptions of the physical characteristics of the three engines, and discusses their performance potentials, as well as their development status.

  17. Modeling the Effects of Turbulence in Rotating Detonation Engines

    NASA Astrophysics Data System (ADS)

    Towery, Colin; Smith, Katherine; Hamlington, Peter; van Schoor, Marthinus; TESLa Team; Midé Team

    2014-03-01

    Propulsion systems based on detonation waves, such as rotating and pulsed detonation engines, have the potential to substantially improve the efficiency and power density of gas turbine engines. Numerous technical challenges remain to be solved in such systems, however, including obtaining more efficient injection and mixing of air and fuels, more reliable detonation initiation, and better understanding of the flow in the ejection nozzle. These challenges can be addressed using numerical simulations. Such simulations are enormously challenging, however, since accurate descriptions of highly unsteady turbulent flow fields are required in the presence of combustion, shock waves, fluid-structure interactions, and other complex physical processes. In this study, we performed high-fidelity three dimensional simulations of a rotating detonation engine and examined turbulent flow effects on the operation, performance, and efficiency of the engine. Along with experimental data, these simulations were used to test the accuracy of commonly-used Reynolds averaged and subgrid-scale turbulence models when applied to detonation engines. The authors gratefully acknowledge the support of the Defense Advanced Research Projects Agency (DARPA).

  18. The European Project Semester at ISEP: the challenge of educating global engineers

    NASA Astrophysics Data System (ADS)

    Malheiro, Benedita; Silva, Manuel; Ribeiro, Maria Cristina; Guedes, Pedro; Ferreira, Paulo

    2015-05-01

    Current engineering education challenges require approaches that promote scientific, technical, design and complementary skills while fostering autonomy, innovation and responsibility. The European Project Semester (EPS) at Instituto Superior de Engenharia do Porto (ISEP) (EPS@ISEP) is a one semester project-based learning programme (30 European Credit Transfer Units (ECTU)) for engineering students from diverse scientific backgrounds and nationalities that intends to address these goals. The students, organised in multidisciplinary and multicultural teams, are challenged to solve real multidisciplinary problems during one semester. The EPS package, although on project development (20 ECTU), includes a series of complementary seminars aimed at fostering soft, project-related and engineering transversal skills (10 ECTU). Hence, the students enrolled in this programme improve their transversal skills and learn, together and with the team of supervisors, subjects distinct from their core training. This paper presents the structure, implementation and results of the EPS@ISEP that was created in 2011 to apply the best engineering practices and promote internationalisation and engineering education innovation at ISEP.

  19. Socio-Technical Perspective on Interdisciplinary Interactions During the Development of Complex Engineered Systems

    NASA Technical Reports Server (NTRS)

    McGowan, Anna-Maria R.; Daly, Shanna; Baker, Wayne; Papalambros, panos; Seifert, Colleen

    2013-01-01

    This study investigates interdisciplinary interactions that take place during the research, development, and early conceptual design phases in the design of large-scale complex engineered systems (LaCES) such as aerospace vehicles. These interactions, that take place throughout a large engineering development organization, become the initial conditions of the systems engineering process that ultimately leads to the development of a viable system. This paper summarizes some of the challenges and opportunities regarding social and organizational issues that emerged from a qualitative study using ethnographic and survey data. The analysis reveals several socio-technical couplings between the engineered system and the organization that creates it. Survey respondents noted the importance of interdisciplinary interactions and their benefits to the engineered system as well as substantial challenges in interdisciplinary interactions. Noted benefits included enhanced knowledge and problem mitigation and noted obstacles centered on organizational and human dynamics. Findings suggest that addressing the social challenges may be a critical need in enabling interdisciplinary interactions

  20. Emerging hypersonic propulsion technology

    NASA Technical Reports Server (NTRS)

    Curran, E. T.; Beach, H. L., Jr.

    1988-01-01

    Currently there is a renewal of interest in the utilization of air breathing engines for hypersonic flight. The use of such engines in accelerative missions is discussed, and the nature of the trade-off between engine thrust-to-weight ratio and specific impulse is highlighted. It is also pointed out that the use of a cryogenic fuel such as liquid hydrogen offers the opportunity to develop both precooled derivatives of turboaccelerator engines and new cryogenic engine cycles, where the heat exchange process plays a significant role in the engine concept. The continuing challenges of developing high speed supersonic combustion ramjet engines are discussed. The paper concludes with a brief review of the difficult discipline of vehicle integration, and the challenges of both ground and flight testing.

  1. 1000539

    NASA Image and Video Library

    2010-04-13

    AYMAN GIRGIS (EM10 MATERIALS TEST ENGINEER, JACOBS ESTS GROUP/JTI) AND ERIC EARHART (AEROSPACE ENGINEER, ER41 PROPULSION STRUCTURAL & DYNAMICS ANALYSIS BRANCH) DISCUSS DATA PRODUCED BY A UNIQUE MECHANICAL TEST SETUP THAT MEASURES STRAIN ON A SINGLE SAMPLE, USING TWO DIFFERENT TECHNIQUES AT THE SAME TIME. THE TEST FIXTURE HOLDS A SPECIMEN THAT REPRESENTS A LIQUID OXYGEN (LOX) BEARING FROM THE J2-X ENGINE.

  2. Estimating Survival Rates in Engineering for Community College Transfer Students Using Grades in Calculus and Physics

    ERIC Educational Resources Information Center

    Laugerman, Marcia; Shelley, Mack; Rover, Diane; Mickelson, Steve

    2015-01-01

    This study uses a unique synthesized set of data for community college students transferring to engineering by combining several cohorts of longitudinal data along with transcript-level data, from both the Community College and the University, to measure success rates in engineering. The success rates are calculated by developing Kaplan-Meier…

  3. Simulating Exposure Concentrations of Engineered Nanomaterials in Surface Water Systems: WASP8

    EPA Science Inventory

    The unique properties of engineered nanomaterials led to their increased production and potential release into the environment. Currently available environmental fate models developed for traditional contaminants are limited in their ability to simulate nanomaterials’ envir...

  4. Putting engineering back into protein engineering: bioinformatic approaches to catalyst design.

    PubMed

    Gustafsson, Claes; Govindarajan, Sridhar; Minshull, Jeremy

    2003-08-01

    Complex multivariate engineering problems are commonplace and not unique to protein engineering. Mathematical and data-mining tools developed in other fields of engineering have now been applied to analyze sequence-activity relationships of peptides and proteins and to assist in the design of proteins and peptides with specified properties. Decreasing costs of DNA sequencing in conjunction with methods to quickly synthesize statistically representative sets of proteins allow modern heuristic statistics to be applied to protein engineering. This provides an alternative approach to expensive assays or unreliable high-throughput surrogate screens.

  5. Engine component instrumentation development facility at NASA Lewis Research Center

    NASA Technical Reports Server (NTRS)

    Bruckner, Robert J.; Buggele, Alvin E.; Lepicovsky, Jan

    1992-01-01

    The Engine Components Instrumentation Development Facility at NASA Lewis is a unique aeronautics facility dedicated to the development of innovative instrumentation for turbine engine component testing. Containing two separate wind tunnels, the facility is capable of simulating many flow conditions found in most turbine engine components. This facility's broad range of capabilities as well as its versatility provide an excellent location for the development of novel testing techniques. These capabilities thus allow a more efficient use of larger and more complex engine component test facilities.

  6. Automotive Control Systems: For Engine, Driveline, and Vehicle

    NASA Astrophysics Data System (ADS)

    Kiencke, Uwe; Nielsen, Lars

    Advances in automotive control systems continue to enhance safety and comfort and to reduce fuel consumption and emissions. Reflecting the trend to optimization through integrative approaches for engine, driveline, and vehicle control, this valuable book enables control engineers to understand engine and vehicle models necessary for controller design, and also introduces mechanical engineers to vehicle-specific signal processing and automatic control. The emphasis on measurement, comparisons between performance and modeling, and realistic examples derive from the authors' unique industrial experience

  7. Dental and Nondental Stem Cell Based Regeneration of the Craniofacial Region: A Tissue Based Approach

    PubMed Central

    Hughes, Declan; Song, Bing

    2016-01-01

    Craniofacial reconstruction may be a necessary treatment for those who have been affected by trauma, disease, or pathological developmental conditions. The use of stem cell therapy and tissue engineering shows massive potential as a future treatment modality. Currently in the literature, there is a wide variety of published experimental studies utilising the different stem cell types available and the plethora of available scaffold materials. This review investigates different stem cell sources and their unique characteristics to suggest an ideal cell source for regeneration of individual craniofacial tissues. At present, understanding and clinical applications of stem cell therapy remain in their infancy with numerous challenges to overcome. In spite of this, the field displays immense capacity and will no doubt be utilised in future clinical treatments of craniofacial regeneration. PMID:27143979

  8. Chemistry and Biology of the Caged Garcinia Xanthones

    PubMed Central

    Chantarasriwong, Oraphin; Batova, Ayse; Chavasiri, Warinthorn

    2011-01-01

    Natural products have been a great source of many small molecule drugs for various diseases. In spite of recent advances in biochemical engineering and fermentation technologies that allow us to explore microorganisms and the marine environment as alternative sources of drugs, more than 70% of the current small molecule therapeutics derive their structures from plants used in traditional medicine. Natural-product-based drug discovery relies heavily on advances made in the sciences of biology and chemistry. Whereas biology aims to investigate the mode of action of a natural product, chemistry aims to overcome challenges related to its supply, bioactivity, and target selectivity. This review summarizes the explorations of the caged Garcinia xanthones, a family of plant metabolites that possess a unique chemical structure, potent bioactivities, and a promising pharmacology for drug design and development. PMID:20648491

  9. Facility design consideration for continuous mix production of class 1.3 propellant

    NASA Technical Reports Server (NTRS)

    Williamson, K. L.; Schirk, P. G.

    1994-01-01

    In November of 1989, NASA awarded the Advanced Solid Rocket Motor (ASRM) contract to Lockheed Missiles and Space Company (LMSC) for production of advanced solid rocket motors using the continuous mix process. Aerojet ASRM division (AAD) was selected as the facility operator and RUST International Corporation provided the engineering, procurement, and construction management services. The continuous mix process mandates that the mix and cast facilities be 'close-coupled' along with the premix facilities, creating unique and challenging requirements for the facility designer. The classical approach to handling energetic materials-division into manageable quantities, segregation, and isolation-was not available due to these process requirements and quantities involved. This paper provides a description of the physical facilities, the continuous mix process, and discusses the monitoring and detection techniques used to mitigate hazards and prevent an incident.

  10. Identification challenges for large space structures

    NASA Technical Reports Server (NTRS)

    Pappa, Richard S.

    1990-01-01

    The paper examines the on-orbit modal identification of large space structures, stressing the importance of planning and experience, in preparation for the Space Station Structural Characterization Experiment (SSSCE) for the Space Station Freedom. The necessary information to foresee and overcome practical difficulties is considered in connection with seven key factors, including test objectives, dynamic complexity of the structure, data quality, extent of exploratory studies, availability and understanding of software tools, experience with similar problems, and pretest analytical conditions. These factors affect identification success in ground tests. Comparisons with similar ground tests of assembled systems are discussed, showing that the constraints of space tests make these factors more significant. The absence of data and experiences relating to on-orbit modal identification testing is shown to make identification a uniquely mathematical problem, although all spacecraft are constructed and verified by proven engineering methods.

  11. NASA Virtual Glovebox: An Immersive Virtual Desktop Environment for Training Astronauts in Life Science Experiments

    NASA Technical Reports Server (NTRS)

    Twombly, I. Alexander; Smith, Jeffrey; Bruyns, Cynthia; Montgomery, Kevin; Boyle, Richard

    2003-01-01

    The International Space Station will soon provide an unparalleled research facility for studying the near- and longer-term effects of microgravity on living systems. Using the Space Station Glovebox Facility - a compact, fully contained reach-in environment - astronauts will conduct technically challenging life sciences experiments. Virtual environment technologies are being developed at NASA Ames Research Center to help realize the scientific potential of this unique resource by facilitating the experimental hardware and protocol designs and by assisting the astronauts in training. The Virtual GloveboX (VGX) integrates high-fidelity graphics, force-feedback devices and real- time computer simulation engines to achieve an immersive training environment. Here, we describe the prototype VGX system, the distributed processing architecture used in the simulation environment, and modifications to the visualization pipeline required to accommodate the display configuration.

  12. A Geology Sampling System for Small Bodies

    NASA Technical Reports Server (NTRS)

    Naids, Adam J.; Hood, Anthony D.; Abell, Paul; Graff, Trevor; Buffington, Jesse

    2016-01-01

    Human exploration of microgravity bodies is being investigated as a precursor to a Mars surface mission. Asteroids, comets, dwarf planets, and the moons of Mars all fall into this microgravity category and some are being discussed as potential mission targets. Obtaining geological samples for return to Earth will be a major objective for any mission to a small body. Currently, the knowledge base for geology sampling in microgravity is in its infancy. Humans interacting with non-engineered surfaces in microgravity environment pose unique challenges. In preparation for such missions a team at the NASA Johnson Space Center has been working to gain experience on how to safely obtain numerous sample types in such an environment. This paper describes the type of samples the science community is interested in, highlights notable prototype work, and discusses an integrated geology sampling solution.

  13. A Geology Sampling System for Microgravity Bodies

    NASA Technical Reports Server (NTRS)

    Hood, Anthony; Naids, Adam

    2016-01-01

    Human exploration of microgravity bodies is being investigated as a precursor to a Mars surface mission. Asteroids, comets, dwarf planets, and the moons of Mars all fall into this microgravity category and some are been discussed as potential mission targets. Obtaining geological samples for return to Earth will be a major objective for any mission to a microgravity body. Currently the knowledge base for geology sampling in microgravity is in its infancy. Humans interacting with non-engineered surfaces in microgravity environment pose unique challenges. In preparation for such missions a team at the NASA Johnson Space Center has been working to gain experience on how to safely obtain numerous sample types in such an environment. This paper describes the type of samples the science community is interested in, highlights notable prototype work, and discusses an integrated geology sampling solution.

  14. Recent Development in Big Data Analytics for Business Operations and Risk Management.

    PubMed

    Choi, Tsan-Ming; Chan, Hing Kai; Yue, Xiaohang

    2017-01-01

    "Big data" is an emerging topic and has attracted the attention of many researchers and practitioners in industrial systems engineering and cybernetics. Big data analytics would definitely lead to valuable knowledge for many organizations. Business operations and risk management can be a beneficiary as there are many data collection channels in the related industrial systems (e.g., wireless sensor networks, Internet-based systems, etc.). Big data research, however, is still in its infancy. Its focus is rather unclear and related studies are not well amalgamated. This paper aims to present the challenges and opportunities of big data analytics in this unique application domain. Technological development and advances for industrial-based business systems, reliability and security of industrial systems, and their operational risk management are examined. Important areas for future research are also discussed and revealed.

  15. Advanced materials and techniques for fibre-optic sensing

    NASA Astrophysics Data System (ADS)

    Henderson, Philip J.

    2014-06-01

    Fibre-optic monitoring systems came of age in about 1999 upon the emergence of the world's first significant commercialising company - a spin-out from the UK's collaborative MAST project. By using embedded fibre-optic technology, the MAST project successfully measured transient strain within high-performance composite yacht masts. Since then, applications have extended from smart composites into civil engineering, energy, military, aerospace, medicine and other sectors. Fibre-optic sensors come in various forms, and may be subject to embedment, retrofitting, and remote interrogation. The unique challenges presented by each implementation require careful scrutiny before widespread adoption can take place. Accordingly, various aspects of design and reliability are discussed spanning a range of representative technologies that include resonant microsilicon structures, MEMS, Bragg gratings, advanced forms of spectroscopy, and modern trends in nanotechnology. Keywords: Fibre-optic sensors, fibre Bragg gratings, MEMS, MOEMS, nanotechnology, plasmon.

  16. Pathways to space: A mission to foster the next generation of scientists and engineers

    NASA Astrophysics Data System (ADS)

    Dougherty, Kerrie; Oliver, Carol; Fergusson, Jennifer

    2014-06-01

    The first education project funded under the Australian Government's Australian Space Research Program (ASRP), Pathways to Space was a unique project combining education, science communication research and research in astrobiology and robotics. It drew upon the challenges of space exploration to inspire students to consider study and careers in science and engineering. A multi-faceted program, Pathways to Space provided hands-on opportunities for high school and university students to participate in realistic simulations of a robotic Mars exploration mission for astrobiology. Its development was a collaboration between the Australian Centre for Astrobiology (University of New South Wales), the Australian Centre for Field Robotics (University of Sydney), the Powerhouse Museum and industry partner, Cisco. Focused on students in Years 9-10 (15-16 years of age), this program provided them with the opportunity to engage directly with space engineers and astrobiologists, while carrying out a simulated Mars mission using the digital learning facilities available at the Powerhouse Museum. As a part of their program, the students operated robotic mini-rovers in the Powerhouse Museum's “Mars Yard”, a highly accurate simulation of the Martian surface, where university students also carry out the development and testing of experimental Mars roving vehicles. This aspect of the program has brought real science and engineering research into the public space of the museum. As they undertook the education program, the students participated in a research study aimed at understanding the effectiveness of the project in achieving its key objective - encouraging students to consider space related courses and careers. This paper outlines the development and operation of the Pathways to Space project over its 3-year funding period, during which it met and exceeded all the requirements of its ASRP grant. It will look at the goals of the project, the rationale behind the education and science communications research, the challenges of developing such a multi-faceted education project in collaboration with several partners and the results that have already been achieved within the study.

  17. YogaHome: teaching and research challenges in a yoga program with homeless adults.

    PubMed

    Davis-Berman, Jennifer; Farkas, Jean

    2012-01-01

    YogaHome is a therapeutic yoga program for homeless women. Developing and refining YogaHome provided a unique opportunity to explore the process of teaching yoga to women faced with the physical and emotional stress of living in a homeless shelter. Unique teaching and research challenges are presented and recommendations for future programs are discussed.

  18. Modernization of the Cassini Ground System

    NASA Technical Reports Server (NTRS)

    Razo, Gus; Fujii, Tammy J.

    2014-01-01

    The Cassini Spacecraft and its ground system have been operational for over 16 years. Modernization presents several challenges due to the personnel, processes, and tools already invested and embedded into the current ground system structure. Every mission's ground system has its own unique complexities and challenges, involving various organizational units. As any mission from its inception to its execution, schedules are always tight. This forces GDS engineers to implement a working ground system that is not necessarily fully optimized. Ground system challenges increase as technology evolves and cyber threats become more sophisticated. Cassini's main challenges were due to its ground system existing before many security requirements were levied on the multi-mission tools and networks. This caused a domino effect on Cassini GDS tools that relied on outdated technological features. In the aerospace industry reliable and established technology is preferred over innovative yet less proven technology. Loss of data for a spacecraft mission can be catastrophic; therefore, there is a reluctance to make changes and updates to the ground system. Nevertheless, all missions and associated teams face the need to modernize their processes and tools. Systems development methods from well-known system analysis and design principles can be applied to many missions' ground systems. Modernization should always be considered, but should be done in such a way that it does not affect flexibility nor interfere with established practices. Cassini has accomplished a secure and efficient ground data system through periodic updates. The obstacles faced while performing the modernization of the Cassini ground system will be outlined, as well as the advantages and challenges that were encountered.

  19. Globalization and Organizational Change: Engineers' Experiences and Their Implications for Engineering Education

    ERIC Educational Resources Information Center

    Lucena, Juan C.

    2006-01-01

    The demand for flexible engineers presents significant challenges to engineering education. Among these is the need for engineers to be prepared to understand and deal with organizational change. Yet engineering education and research on engineers have overlooked the impact of organizational change on engineering work. After outlining the impact…

  20. Brain Metastasis: Unique Challenges and Open Opportunities

    PubMed Central

    Lowery, Frank J.; Yu, Dihua

    2016-01-01

    The metastasis of cancer to the central nervous system (CNS) remains a devastating clinical reality, carrying an estimated survival time of less than one year in spite of recent therapeutic breakthroughs for other disease contexts. Advances in brain metastasis research are hindered by a number of reasons, including its complicated nature and the difficulty of modeling metastatic cancer growth in the unique brain microenvironment. In this review, we will discuss the clinical challenge, and compare the values and limitations of the available models for brain metastasis research. Additionally, we will specifically address current knowledge on how brain metastases take advantage of the unique brain environment to benefit their own growth. Finally, we will explore the distinctive metabolic and nutrient characteristics of the brain; how these paradoxically represent barriers to establishment of brain metastasis, but also provide ample supplies for metastatic cells’ growth in the brain. We envision that multi-disciplinary innovative approaches will open opportunities for the field to make breakthroughs in tackling unique challenges of brain metastasis. PMID:27939792

  1. Geo-Hazards and Mountain Road Development in Nepal: Understanding the Science-Policy-Governance Interface

    NASA Astrophysics Data System (ADS)

    Dugar, Sumit; Dahal, Vaskar

    2015-04-01

    The foothills of Nepalese Himalayas located in the neotectonic mountain environment are among some of the most unstable and geomorphologically dynamic landscapes in the world. Young fold mountains in this region are characterized by complex tectonics that influence the occurrence of earthquakes, while climatic processes such as intense orographic rainfall often dictate the occurrence of floods and landslides. Development of linear infrastructures, such as roads, in mountainous terrain characterized by high relief and orogeny is considerably challenging where the complexity of landscape in steep and irregular topography, difficult ground conditions and weak geology, presents engineers and planners with numerous difficulties to construct and maintain mountain roads. Whilst application of engineering geology, geomorphic interpretation of terrain in terms of physiography and hydrology, and identification of geo-hazards along the road corridor is critical for long term operation of mountain roads, low-cost arterial roads in the Himalayan foothills generally fail to incorporate standard road slope engineering structures. This research provides unique insights on policy and governance issues in developing mountainous countries such as Nepal, where achieving a sound balance between sustainability and affordability is a major challenge for road construction. Road development in Nepal is a complex issue where socio-economic and political factors influence the budget allocation for road construction in rural hilly areas. Moreover, most mountain roads are constructed without any geological or geo-technical site investigations due to rampant corruption and lack of adequate engineering supervision. Despite having good examples of rural road construction practices such as the Dharan-Dhankuta Road in Eastern Nepal where comprehensive terrain-evaluation methods and geo-technical surveys led to an improved understanding of road construction, learnings from this project have not informed other road development schemes in Nepal. Geomorphological surveys and robust geo-hazard assessments that factor the spatial and temporal dimensions of the seismic, fluvial and sediment hazards along the road corridor are critical for sustainable development of mountain roads. However, scientific and technical research studies seldom inform mountain road development primarily due to lack of co-ordination between the respective government agencies, access to journal papers in developing countries and unwillingness to adopt novel interventions in rural road construction practices. These challenges are further exacerbated by weak governance and lack of proper policy enforcement that often leads to construction of poorly engineered roads, thereby increasing the risk of rural infrastructural damage from geo-hazards. Though there exists a disconnect between the science-policy-governance interface where information on geo-hazards is neglected in mountain road development due to lack of scientific research and government apathy, there is an opportunity to spur dialogue and sensitize these issues via trans-disciplinary approaches on disaster risk management.

  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. Interoperable Acquisition for Systems of Systems: The Challenges

    DTIC Science & Technology

    2006-09-01

    Interoperable Acquisition for Systems of Systems: The Challenges James D. Smith II D. Mike Phillips September 2006 TECHNICAL NOTE...Failure of Program-Centric Risk Management 10 3.3.2 Absence of System-of-Systems Engineering 12 3.3.3 Disconnect Between System-of-Systems...SOFTWARE ENGINEERING INSTITUTE | vii viii | CMU/SEI-2006-TN-034 Abstract Large, complex systems development has always been challenging , even when the

  4. Nanotechnology: toxicologic pathology.

    PubMed

    Hubbs, Ann F; Sargent, Linda M; Porter, Dale W; Sager, Tina M; Chen, Bean T; Frazer, David G; Castranova, Vincent; Sriram, Krishnan; Nurkiewicz, Timothy R; Reynolds, Steven H; Battelli, Lori A; Schwegler-Berry, Diane; McKinney, Walter; Fluharty, Kara L; Mercer, Robert R

    2013-02-01

    Nanotechnology involves technology, science, and engineering in dimensions less than 100 nm. A virtually infinite number of potential nanoscale products can be produced from many different molecules and their combinations. The exponentially increasing number of nanoscale products will solve critical needs in engineering, science, and medicine. However, the virtually infinite number of potential nanotechnology products is a challenge for toxicologic pathologists. Because of their size, nanoparticulates can have therapeutic and toxic effects distinct from micron-sized particulates of the same composition. In the nanoscale, distinct intercellular and intracellular translocation pathways may provide a different distribution than that obtained by micron-sized particulates. Nanoparticulates interact with subcellular structures including microtubules, actin filaments, centrosomes, and chromatin; interactions that may be facilitated in the nanoscale. Features that distinguish nanoparticulates from fine particulates include increased surface area per unit mass and quantum effects. In addition, some nanotechnology products, including the fullerenes, have a novel and reactive surface. Augmented microscopic procedures including enhanced dark-field imaging, immunofluorescence, field-emission scanning electron microscopy, transmission electron microscopy, and confocal microscopy are useful when evaluating nanoparticulate toxicologic pathology. Thus, the pathology assessment is facilitated by understanding the unique features at the nanoscale and the tools that can assist in evaluating nanotoxicology studies.

  5. Space Human Factors Engineering Gap Analysis Project Final Report

    NASA Technical Reports Server (NTRS)

    Hudy, Cynthia; Woolford, Barbara

    2006-01-01

    Humans perform critical functions throughout each phase of every space mission, beginning with the mission concept and continuing to post-mission analysis (Life Sciences Division, 1996). Space missions present humans with many challenges - the microgravity environment, relative isolation, and inherent dangers of the mission all present unique issues. As mission duration and distance from Earth increases, in-flight crew autonomy will increase along with increased complexity. As efforts for exploring the moon and Mars advance, there is a need for space human factors research and technology development to play a significant role in both on-orbit human-system interaction, as well as the development of mission requirements and needs before and after the mission. As part of the Space Human Factors Engineering (SHFE) Project within the Human Research Program (HRP), a six-month Gap Analysis Project (GAP) was funded to identify any human factors research gaps or knowledge needs. The overall aim of the project was to review the current state of human factors topic areas and requirements to determine what data, processes, or tools are needed to aid in the planning and development of future exploration missions, and also to prioritize proposals for future research and technology development.

  6. Nanotechnology: Toxicologic Pathology

    PubMed Central

    Hubbs, Ann F.; Sargent, Linda M.; Porter, Dale W.; Sager, Tina M.; Chen, Bean T.; Frazer, David G.; Castranova, Vincent; Sriram, Krishnan; Nurkiewicz, Timothy R.; Reynolds, Steven H.; Battelli, Lori A.; Schwegler-Berry, Diane; McKinney, Walter; Fluharty, Kara L.; Mercer, Robert R.

    2015-01-01

    Nanotechnology involves technology, science, and engineering in dimensions less than 100 nm. A virtually infinite number of potential nanoscale products can be produced from many different molecules and their combinations. The exponentially increasing number of nanoscale products will solve critical needs in engineering, science, and medicine. However, the virtually infinite number of potential nanotechnology products is a challenge for toxicologic pathologists. Because of their size, nanoparticulates can have therapeutic and toxic effects distinct from micron-sized particulates of the same composition. In the nanoscale, distinct intercellular and intracellular translocation pathways may provide a different distribution than that obtained by micron-sized particulates. Nanoparticulates interact with subcellular structures including microtubules, actin filaments, centrosomes, and chromatin; interactions that may be facilitated in the nanoscale. Features that distinguish nanoparticulates from fine particulates include increased surface area per unit mass and quantum effects. In addition, some nanotechnology products, including the fullerenes, have a novel and reactive surface. Augmented microscopic procedures including enhanced dark-field imaging, immunofluorescence, field-emission scanning electron microscopy, transmission electron microscopy, and confocal microscopy are useful when evaluating nanoparticulate toxicologic pathology. Thus, the pathology assessment is facilitated by understanding the unique features at the nanoscale and the tools that can assist in evaluating nanotoxicology studies. PMID:23389777

  7. Ultrahigh Elastic Strain Energy Storage in Metal-Oxide-Infiltrated Patterned Hybrid Polymer Nanocomposites

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

    Dusoe, Keith J.; Ye, Xinyi; Kisslinger, Kim

    Modulus of resilience, the measure of a material’s capacity to store and release elastic strain energy, is critical for realizing advanced mechanical actuation technologies in micro/nanoelectromechanical systems. In general, engineering the modulus of resilience is difficult because it requires asymmetrically increasing yield strength and Young’s modulus against their mutual scaling behavior. This task becomes further challenging if it needs to be carried out at the nanometer scale. Here, we demonstrate organic–inorganic hybrid composite nanopillars with one of the highest modulus of resilience per density by utilizing vapor-phase aluminum oxide infiltration in lithographically patterned negative photoresist SU-8. In situ nanomechanical measurementsmore » reveal a metal-like high yield strength (~500 MPa) with an unusually low, foam-like Young’s modulus (~7 GPa), a unique pairing that yields ultrahigh modulus of resilience, reaching up to ~24 MJ/m 3 as well as exceptional modulus of resilience per density of ~13.4 kJ/kg, surpassing those of most engineering materials. The hybrid polymer nanocomposite features lightweight, ultrahigh tunable modulus of resilience and versatile nanoscale lithographic patternability with potential for application as nanomechanical components which require ultrahigh mechanical resilience and strength.« less

  8. Ultrahigh Elastic Strain Energy Storage in Metal-Oxide-Infiltrated Patterned Hybrid Polymer Nanocomposites

    DOE PAGES

    Dusoe, Keith J.; Ye, Xinyi; Kisslinger, Kim; ...

    2017-10-19

    Modulus of resilience, the measure of a material’s capacity to store and release elastic strain energy, is critical for realizing advanced mechanical actuation technologies in micro/nanoelectromechanical systems. In general, engineering the modulus of resilience is difficult because it requires asymmetrically increasing yield strength and Young’s modulus against their mutual scaling behavior. This task becomes further challenging if it needs to be carried out at the nanometer scale. Here, we demonstrate organic–inorganic hybrid composite nanopillars with one of the highest modulus of resilience per density by utilizing vapor-phase aluminum oxide infiltration in lithographically patterned negative photoresist SU-8. In situ nanomechanical measurementsmore » reveal a metal-like high yield strength (~500 MPa) with an unusually low, foam-like Young’s modulus (~7 GPa), a unique pairing that yields ultrahigh modulus of resilience, reaching up to ~24 MJ/m 3 as well as exceptional modulus of resilience per density of ~13.4 kJ/kg, surpassing those of most engineering materials. The hybrid polymer nanocomposite features lightweight, ultrahigh tunable modulus of resilience and versatile nanoscale lithographic patternability with potential for application as nanomechanical components which require ultrahigh mechanical resilience and strength.« less

  9. Constraints and Opportunities in GCM Model Development

    NASA Technical Reports Server (NTRS)

    Schmidt, Gavin; Clune, Thomas

    2010-01-01

    Over the past 30 years climate models have evolved from relatively simple representations of a few atmospheric processes to complex multi-disciplinary system models which incorporate physics from bottom of the ocean to the mesopause and are used for seasonal to multi-million year timescales. Computer infrastructure over that period has gone from punchcard mainframes to modern parallel clusters. Constraints of working within an ever evolving research code mean that most software changes must be incremental so as not to disrupt scientific throughput. Unfortunately, programming methodologies have generally not kept pace with these challenges, and existing implementations now present a heavy and growing burden on further model development as well as limiting flexibility and reliability. Opportunely, advances in software engineering from other disciplines (e.g. the commercial software industry) as well as new generations of powerful development tools can be incorporated by the model developers to incrementally and systematically improve underlying implementations and reverse the long term trend of increasing development overhead. However, these methodologies cannot be applied blindly, but rather must be carefully tailored to the unique characteristics of scientific software development. We will discuss the need for close integration of software engineers and climate scientists to find the optimal processes for climate modeling.

  10. LANL Contributions to the B61 LIfe Extension Program

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

    Corpion, Juan Carlos

    2016-02-10

    The Los Alamos National Laboratory (LANL) has a long, proud heritage in science and innovation that extends 70 years. Although the Laboratory’s primary responsibility is assuring the safety and reliability of the nation’s nuclear deterrent, Laboratory staff work on a broad range of advanced technologies to provide the best, most effective scientific and engineering solutions to the nation’s critical security challenges. The world is rapidly changing, but this essential responsibility remains the LANL’s core mission. LANL is the Design Laboratory for the nuclear explosive package of the B61 Air Force bomb. The B61-12 Life Extension Program (LEP) activities at LANLmore » will increase the lifetime of the bomb and provide safety and security options to meet security environments both today and in the future. The B61’s multiple-platform functionality, unique safety features, and large number of components make the B61-12 LEP one of the most complex LEPs ever attempted. Over 230 LANL scientists, engineers, technicians, and support personnel from across the Laboratory are bringing decades of interdisciplinary knowledge, technical expertise, and leading-edge capabilities to LANL’s work on the LEP.« less

  11. Public health engineering education in India: current scenario, opportunities and challenges.

    PubMed

    Hussain, Mohammad Akhtar; Sharma, Kavya; Zodpey, Sanjay

    2011-01-01

    Public health engineering can play an important and significant role in solving environmental health issues. In order to confront public health challenges emerging out of environmental problems we need adequately trained public health engineers / environmental engineers. Considering the current burden of disease attributable to environmental factors and expansion in scope of applications of public health / environmental engineering science, it is essential to understand the present scenario of teaching, training and capacity building programs in these areas. Against this background the present research was carried out to know the current teaching and training programs in public health engineering and related disciplines in India and to understand the potential opportunities and challenges available. A systematic, predefined approach was used to collect and assemble the data related to various teaching and training programs in public health engineering / environmental engineering in India. Public health engineering / environmental engineering education and training in the country is mainly offered through engineering institutions, as pre-service and in-service training. Pre-service programs include diploma, degree (graduate) and post-graduate courses affiliated to various state technical boards, institutes and universities, whereas in-service training is mainly provided by Government of India recognized engineering and public health training institutes. Though trainees of these programs acquire skills related to engineering sciences, they significantly lack in public health skills. The teaching and training of public health engineering / environmental engineering is limited as a part of public health programs (MD Community Medicine, MPH, DPH) in India. There is need for developing teaching and training of public health engineering or environmental engineering as an interdisciplinary subject. Public health institutes can play an important and significant role in this regard by engaging themselves in initiating specialized programs in this domain.

  12. Managing large energy and mineral resources (EMR) projects in challenging environments

    NASA Astrophysics Data System (ADS)

    Chanmeka, Arpamart

    The viability of energy mineral resources (EMR) construction projects is contingent upon the state of the world economic climate. Oil sands projects in Alberta, Canada exemplify large EMR projects that are highly sensitive to fluctuations in the world market. Alberta EMR projects are constrained by high fixed production costs and are also widely recognized as one of the most challenging construction projects to successfully deliver due to impacts from extreme weather conditions, remote locations and issues with labor availability amongst others. As indicated in many studies, these hardships strain the industry's ability to execute work efficiently, resulting in declining productivity and mounting cost and schedule overruns. Therefore, to enhance the competitiveness of Alberta EMR projects, project teams are targeting effective management strategies to enhance project performance and productivity by countering the uniquely challenging environment in Alberta. The main purpose of this research is to develop industry wide benchmarking tailored to the specific constraints and challenges of Alberta. Results support quantitative assessments and identify the root causes of project performance and ineffective field productivity problems in the heavy industry sector capital projects. Customized metrics produced from the data collected through a web-based survey instrument were used to quantitatively assess project performance in the following dimensions: cost, schedule, change, rework, safety, engineering and construction productivity and construction practices. The system enables the industry to measure project performance more accurately, get meaningful comparisons, while establishing credible norms specific to Alberta projects. Data analysis to identify the root cause of performance problems was conducted. The analysis of Alberta projects substantiated lessons of previous studies to create an improved awareness of the abilities of Alberta-based companies to manage their unique projects. This investigation also compared Alberta-based projects with U.S. projects to point out the differences in project process and management strategies under different environments. The relative impact of factors affecting construction productivity were identified and validated by the input from industry experts. The findings help improve the work processes used by companies developing projects in Alberta.

  13. 40 CFR 94.908 - National security exemption.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES Exclusion and Exemption Provisions § 94.908 National security exemption. (a)(1) Any marine engine, otherwise subject to this part, that is... armor, permanently affixed weaponry, specialized electronic warfare systems, unique stealth performance...

  14. 40 CFR 94.908 - National security exemption.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES Exclusion and Exemption Provisions § 94.908 National security exemption. (a)(1) Any marine engine, otherwise subject to this part, that is... armor, permanently affixed weaponry, specialized electronic warfare systems, unique stealth performance...

  15. 40 CFR 94.908 - National security exemption.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES Exclusion and Exemption Provisions § 94.908 National security exemption. (a)(1) Any marine engine, otherwise subject to this part, that is... armor, permanently affixed weaponry, specialized electronic warfare systems, unique stealth performance...

  16. 40 CFR 94.908 - National security exemption.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES Exclusion and Exemption Provisions § 94.908 National security exemption. (a)(1) Any marine engine, otherwise subject to this part, that is... armor, permanently affixed weaponry, specialized electronic warfare systems, unique stealth performance...

  17. 40 CFR 94.908 - National security exemption.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) CONTROL OF EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES Exclusion and Exemption Provisions § 94.908 National security exemption. (a)(1) Any marine engine, otherwise subject to this part, that is... armor, permanently affixed weaponry, specialized electronic warfare systems, unique stealth performance...

  18. Rotary-Wing Relevant Compressor Aero Research and Technology Development Activities at Glenn Research Center

    NASA Technical Reports Server (NTRS)

    Welch, Gerard E.; Hathaway, Michael D.; Skoch, Gary J.; Snyder, Christopher A.

    2012-01-01

    Technical challenges of compressors for future rotorcraft engines are driven by engine-level and component-level requirements. Cycle analyses are used to highlight the engine-level challenges for 3000, 7500, and 12000 SHP-class engines, which include retention of performance and stability margin at low corrected flows, and matching compressor type, axial-flow or centrifugal, to the low corrected flows and high temperatures in the aft stages. At the component level: power-to-weight and efficiency requirements impel designs with lower inherent aerodynamic stability margin; and, optimum engine overall pressure ratios lead to small blade heights and the associated challenges of scale, particularly increased clearance-to-span ratios. The technical challenges associated with the aerodynamics of low corrected flows and stability management impel the compressor aero research and development efforts reviewed herein. These activities include development of simple models for clearance sensitivities to improve cycle calculations, full-annulus, unsteady Navier-Stokes simulations used to elucidate stall, its inception, and the physics of stall control by discrete tip-injection, development of an actuator-duct-based model for rapid simulation of nonaxisymmetric flow fields (e.g., due inlet circumferential distortion), advanced centrifugal compressor stage development and experimentation, and application of stall control in a T700 engine.

  19. Bringing nanomedicines to market: regulatory challenges, opportunities, and uncertainties.

    PubMed

    Nijhara, Ruchika; Balakrishnan, Krishna

    2006-06-01

    Scientists and entrepreneurs who contemplate developing nanomedicine products face several unique challenges in addition to many of the traditional hurdles of product development. In this review we analyze the major physicochemical, biologic and functional characteristics of several nanomedicine products on the market and explore the question of what made them unique. What made them successful? We also focus on the regulatory challenges faced by nanomedicine product developers. Based on these analyses, we propose the factors that are most likely to contribute to the success of nanomedicine products.

  20. Nanotechnology: Scientific challenges and societal benefits and risks

    NASA Astrophysics Data System (ADS)

    Romig, A. D.

    2004-12-01

    The field of nanotechnology is developing rapidly, as are its practical application in society. In this article, we give examples that demonstrate the enormous potential that exists for this new class of materials, and for devices with critical dimensions of less than 100 nm. We also identify some of the challenges that need to be faced in order to fully realize the practical benefits of nanotechnology, and discuss possible risks that may come with this new technology. In all cases, the unique advantage of nanotechnology can be traced back to nanoscale physical and chemical properties that are quite different from those encountered in more traditional microscopic (micro) or macroscopic (macro) materials and devices. Unique nanoscale properties and behaviors are already being used to increase energy efficiency, improve healthcare, and strengthen national security. However, while progress is rapid, many challenges remain. These include manufacturing at the nanoscale, integration of nanoscale materials and devices with more conventional technology, and predictive modeling that will allow nanotechnology to be engineered reliably into useful applications and products. Nanotechnology can be expected to have an increasing impact on human lives and society at large. As we strive to use nanotechnology to improve human life through better healthcare, cleaner environment, and improved national security, we must also work to detect and assess the negative impacts that nanotechnology science (or any new technology) might bring. We suggest that the conduct of should be allowed to proceed unimpeded, so that we can fully understand and appreciate the rules of nature at the nanometer scale. That said, scientific pursuits that involve self-replication in synthetic systems, encryption, defense technology, or the enhancement of human intelligence should be reviewed. The development of new technology from fundamental science and the process of deciding what new technology is to be created for what purpose are topics for reasoned debate among the general public as well as in the forums of scientific peer review and political decision making.

  1. The common engine concept for ALS application - A cost reduction approach

    NASA Technical Reports Server (NTRS)

    Bair, E. K.; Schindler, C. M.

    1989-01-01

    Future launch systems require the application of propulsion systems which have been designed and developed to meet mission model needs while providing high degrees of reliability and cost effectiveness. Vehicle configurations which utilize different propellant combinations for booster and core stages can benefit from a common engine approach where a single engine design can be configured to operate on either set of propellants and thus serve as either a booster or core engine. Engine design concepts and mission application for a vehicle employing a common engine are discussed. Engine program cost estimates were made and cost savings, over the design and development of two unique engines, estimated.

  2. Advanced technology payoffs for future rotorcraft, commuter aircraft, cruise missile, and APU propulsion systems

    NASA Technical Reports Server (NTRS)

    Turk, M. A.; Zeiner, P. K.

    1986-01-01

    In connection with the significant advances made regarding the performance of larger gas turbines, challenges arise concerning the improvement of small gas turbine engines in the 250 to 1000 horsepower range. In response to these challenges, the NASA/Army-sponsored Small Engine Component Technology (SECT) study was undertaken with the objective to identify the engine cycle, configuration, and component technology requirements for the substantial performance improvements desired in year-2000 small gas turbine engines. In the context of this objective, an American turbine engine company evaluated engines for four year-2000 applications, including a rotorcraft, a commuter aircraft, a supersonic cruise missile, and an auxiliary power unit (APU). Attention is given to reference missions, reference engines, reference aircraft, year-2000 technology projections, cycle studies, advanced engine selections, and a technology evaluation.

  3. Structural Engineering Managers - Innovation Challenges for their Skills

    NASA Astrophysics Data System (ADS)

    Linkeschová, D.; Tichá, A.

    2015-11-01

    The profession of a structural engineer is highly responsible, because the consequences of a structural engineer's errors result not only in economic damage to the property and often irreversible damage to the environment, they can also lead to direct loss of lives. In the current turbulent, dynamically developing society the managerial methods of structural engineers should not stagnate at the level of the last century applications. This paper deals with the challenges which the ongoing century poses to structural engineers and managers. It compares the results of research regarding the current state of managerial skills of structural engineers in Czech building companies to the defined skills of the 21st century's managers according to the global research programme ITL Research and according to the Vision for the Future of Structural Engineering, drawn up by Structural Engineering Institute - SEI ASCE.

  4. Tissue engineering: state of the art in oral rehabilitation

    PubMed Central

    SCHELLER, E. L.; KREBSBACH, P. H.; KOHN, D. H.

    2009-01-01

    SUMMARY More than 85% of the global population requires repair or replacement of a craniofacial structure. These defects range from simple tooth decay to radical oncologic craniofacial resection. Regeneration of oral and craniofacial tissues presents a formidable challenge that requires synthesis of basic science, clinical science and engineering technology. Identification of appropriate scaffolds, cell sources and spatial and temporal signals (the tissue engineering triad) is necessary to optimize development of a single tissue, hybrid organ or interface. Furthermore, combining the understanding of the interactions between molecules of the extracellular matrix and attached cells with an understanding of the gene expression needed to induce differentiation and tissue growth will provide the design basis for translating basic science into rationally developed components of this tissue engineering triad. Dental tissue engineers are interested in regeneration of teeth, oral mucosa, salivary glands, bone and periodontium. Many of these oral structures are hybrid tissues. For example, engineering the periodontium requires growth of alveolar bone, cementum and the periodontal ligament. Recapitulation of biological development of hybrid tissues and interfaces presents a challenge that exceeds that of engineering just a single tissue. Advances made in dental interface engineering will allow these tissues to serve as model systems for engineering other tissues or organs of the body. This review will begin by covering basic tissue engineering principles and strategic design of functional biomaterials. We will then explore the impact of biomaterials design on the status of craniofacial tissue engineering and current challenges and opportunities in dental tissue engineering. PMID:19228277

  5. Tissue engineering: state of the art in oral rehabilitation.

    PubMed

    Scheller, E L; Krebsbach, P H; Kohn, D H

    2009-05-01

    More than 85% of the global population requires repair or replacement of a craniofacial structure. These defects range from simple tooth decay to radical oncologic craniofacial resection. Regeneration of oral and craniofacial tissues presents a formidable challenge that requires synthesis of basic science, clinical science and engineering technology. Identification of appropriate scaffolds, cell sources and spatial and temporal signals (the tissue engineering triad) is necessary to optimize development of a single tissue, hybrid organ or interface. Furthermore, combining the understanding of the interactions between molecules of the extracellular matrix and attached cells with an understanding of the gene expression needed to induce differentiation and tissue growth will provide the design basis for translating basic science into rationally developed components of this tissue engineering triad. Dental tissue engineers are interested in regeneration of teeth, oral mucosa, salivary glands, bone and periodontium. Many of these oral structures are hybrid tissues. For example, engineering the periodontium requires growth of alveolar bone, cementum and the periodontal ligament. Recapitulation of biological development of hybrid tissues and interfaces presents a challenge that exceeds that of engineering just a single tissue. Advances made in dental interface engineering will allow these tissues to serve as model systems for engineering other tissues or organs of the body. This review will begin by covering basic tissue engineering principles and strategic design of functional biomaterials. We will then explore the impact of biomaterials design on the status of craniofacial tissue engineering and current challenges and opportunities in dental tissue engineering.

  6. Workforce Challenges and Retention Success Stories

    NASA Technical Reports Server (NTRS)

    Donohue, John T.

    2008-01-01

    This viewgraph document discusses the current and future challenges in building and retaining the required workforce of scientist and engineers for NASA. Specifically, the talk reviews the current situation at the Goddard Space Flight Center in Greenbelt, Maryland. Several programs at NASA for high school and college students to assist in inspiring the next generation of scientist and engineers are reviewed. The issue of retention of the best of the young scientists and engineers is also reviewed, with a brief review of several young engineers and their success with and for NASA.

  7. Challenges and Opportunities: Building a Relationship Between a Department of Biomedical Engineering and a Medical School.

    PubMed

    George, Steven C; Meyerand, M Elizabeth

    2017-03-01

    A department of biomedical engineering can significantly enhance the impact of their research and training programs if a productive relationship with a medical school can be established. In order to develop such a relationship, significant hurdles must be overcome. This editorial summarizes some of the major challenges and opportunities for a department of biomedical engineering as they seek to build or enhance a relationship with a medical school. The ideas were formulated by engaging the collective wisdom from the Council of Chairs of the biomedical engineering departments.

  8. Regenerative therapy and tissue engineering for the treatment of end-stage cardiac failure: new developments and challenges.

    PubMed

    Finosh, G T; Jayabalan, Muthu

    2012-01-01

    Regeneration of myocardium through regenerative therapy and tissue engineering is appearing as a prospective treatment modality for patients with end-stage heart failure. Focusing on this area, this review highlights the new developments and challenges in the regeneration of myocardial tissue. The role of various cell sources, calcium ion and cytokine on the functional performance of regenerative therapy is discussed. The evolution of tissue engineering and the role of tissue matrix/scaffold, cell adhesion and vascularisation on tissue engineering of cardiac tissue implant are also discussed.

  9. RL10 Engine Ability to Transition from Atlas to Shuttle/Centaur Program

    NASA Technical Reports Server (NTRS)

    Baumeister, Joseph F.

    2015-01-01

    A key launch vehicle design feature is the ability to take advantage of new technologies while minimizing expensive and time consuming development and test programs. With successful space launch experiences and the unique features of both the National Aeronautics and Space Administration (NASA) Space Transportation System (Space Shuttle) and Atlas/Centaur programs, it became attractive to leverage these capabilities. The Shuttle/Centaur Program was created to transition the existing Centaur vehicle to be launched from the Space Shuttle cargo bay. This provided the ability to launch heaver and larger payloads, and take advantage of new unique launch operational capabilities. A successful Shuttle/Centaur Program required the Centaur main propulsion system to quickly accommodate the new operating conditions for two new Shuttle/Centaur configurations and evolve to function in the human Space Shuttle environment. This paper describes the transition of the Atlas/Centaur RL10 engine to the Shuttle/Centaur configurations; shows the unique versatility and capability of the engine; and highlights the importance of ground testing. Propulsion testing outcomes emphasize the value added benefits of testing heritage hardware and the significant impact to existing and future programs.

  10. RL10 Engine Ability to Transition from Atlas to Shuttle/Centaur Program

    NASA Technical Reports Server (NTRS)

    Baumeister, Joseph F.

    2014-01-01

    A key launch vehicle design feature is the ability to take advantage of new technologies while minimizing expensive and time consuming development and test programs. With successful space launch experiences and the unique features of both the National Aeronautics and Space Administration (NASA) Space Transportation System (Space Shuttle) and Atlas/Centaur programs, it became attractive to leverage these capabilities. The Shuttle/Centaur Program was created to transition the existing Centaur vehicle to be launched from the Space Shuttle cargo bay. This provided the ability to launch heaver and larger payloads, and take advantage of new unique launch operational capabilities. A successful Shuttle/Centaur Program required the Centaur main propulsion system to quickly accommodate the new operating conditions for two new Shuttle/Centaur configurations and evolve to function in the human Space Shuttle environment. This paper describes the transition of the Atlas/Centaur RL10 engine to the Shuttle/Centaur configurations; shows the unique versatility and capability of the engine; and highlights the importance of ground testing. Propulsion testing outcomes emphasize the value added benefits of testing heritage hardware and the significant impact to existing and future programs.

  11. Can modeling of HIV treatment processes improve outcomes? Capitalizing on an operations research approach to the global pandemic

    PubMed Central

    Xiong, Wei; Hupert, Nathaniel; Hollingsworth, Eric B; O'Brien, Megan E; Fast, Jessica; Rodriguez, William R

    2008-01-01

    Background Mathematical modeling has been applied to a range of policy-level decisions on resource allocation for HIV care and treatment. We describe the application of classic operations research (OR) techniques to address logistical and resource management challenges in HIV treatment scale-up activities in resource-limited countries. Methods We review and categorize several of the major logistical and operational problems encountered over the last decade in the global scale-up of HIV care and antiretroviral treatment for people with AIDS. While there are unique features of HIV care and treatment that pose significant challenges to effective modeling and service improvement, we identify several analogous OR-based solutions that have been developed in the service, industrial, and health sectors. Results HIV treatment scale-up includes many processes that are amenable to mathematical and simulation modeling, including forecasting future demand for services; locating and sizing facilities for maximal efficiency; and determining optimal staffing levels at clinical centers. Optimization of clinical and logistical processes through modeling may improve outcomes, but successful OR-based interventions will require contextualization of response strategies, including appreciation of both existing health care systems and limitations in local health workforces. Conclusion The modeling techniques developed in the engineering field of operations research have wide potential application to the variety of logistical problems encountered in HIV treatment scale-up in resource-limited settings. Increasing the number of cross-disciplinary collaborations between engineering and public health will help speed the appropriate development and application of these tools. PMID:18680594

  12. Status, Vision, and Challenges of an Intelligent Distributed Engine Control Architecture

    NASA Technical Reports Server (NTRS)

    Behbahani, Alireza; Culley, Dennis; Garg, Sanjay; Millar, Richard; Smith, Bert; Wood, Jim; Mahoney, Tim; Quinn, Ronald; Carpenter, Sheldon; Mailander, Bill; hide

    2007-01-01

    A Distributed Engine Control Working Group (DECWG) consisting of the Department of Defense (DoD), the National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) and industry has been formed to examine the current and future requirements of propulsion engine systems. The scope of this study will include an assessment of the paradigm shift from centralized engine control architecture to an architecture based on distributed control utilizing open system standards. Included will be a description of the work begun in the 1990's, which continues today, followed by the identification of the remaining technical challenges which present barriers to on-engine distributed control.

  13. Engineering Education in K-12 Schools

    NASA Astrophysics Data System (ADS)

    Spence, Anne

    2013-03-01

    Engineers rely on physicists as well as other scientists and mathematicians to explain the world in which we live. Engineers take this knowledge of the world and use it to create the world that never was. The teaching of physics and other sciences as well as mathematics is critical to maintaining our national workforce. Science and mathematics education are inherently different, however, from engineering education. Engineering educators seek to enable students to develop the habits of mind critical for innovation. Through understanding of the engineering design process and how it differs from the scientific method, students can apply problem and project based learning to solve the challenges facing society today. In this talk, I will discuss the elements critical to a solid K-12 engineering education that integrates science and mathematics to solve challenges throughout the world.

  14. Modeling Primary Atomization Processes

    DTIC Science & Technology

    1999-02-01

    consumable , catalytic igniter has shown to provide reliable, reproducible ignition in hydrogen peroxide/polyethylene hybrid engines. Currently, a...verified in a hybrid rocket using hydrogen peroxide as oxidizer and polyethylene as fuel. The engine made use of a unique Consumable Catalytic Bed (CCB...interest to the liquid and hybrid rocket engine community. TECHNOLOGY TRANSFER Performer Customer Result Application 1 S. D. Heister Purdue University

  15. Unique Education and Workforce Development for NASA Engineers

    NASA Technical Reports Server (NTRS)

    Forsgren, Roger C.; Miller, Lauren L.

    2010-01-01

    NASA engineers are some of the world's best-educated graduates, responsible for technically complex, highly significant scientific programs. Even though these professionals are highly proficient in traditional analytical competencies, there is a unique opportunity to offer continuing education that further enhances their overall scientific minds. With a goal of maintaining the Agency's passionate, "best in class" engineering workforce, the NASA Academy of Program/Project & Engineering Leadership (APPEL) provides educational resources encouraging foundational learning, professional development, and knowledge sharing. NASA APPEL is currently partnering with the scientific community's most respected subject matter experts to expand its engineering curriculum beyond the analytics and specialized subsystems in the areas of: understanding NASA's overall vision and its fundamental basis, and the Agency initiatives supporting them; sharing NASA's vast reservoir of engineering experience, wisdom, and lessons learned; and innovatively designing hardware for manufacturability, assembly, and servicing. It takes collaboration and innovation to educate an organization that possesses such a rich and important historyand a future that is of great global interest. NASA APPEL strives to intellectually nurture the Agency's technical professionals, build its capacity for future performance, and exemplify its core valuesalJ to better enable NASA to meet its strategic visionand beyond.

  16. Arsenic Adsorption and As (III) Oxidation on TiO2 Nanoparticles: Macroscopic and Spectroscopic Investigations

    EPA Science Inventory

    Engineered nanoparticles (NPs) (particle sizes ranging from 1-100 nm) have unique physical and chemical properties that differ fundamentally from their macro-sized counterparts. In addition to their smaller particle size, nanoparticles possess unique characteristics such as larg...

  17. Grand challenge commentary: Transforming biosynthesis into an information science.

    PubMed

    Bayer, Travis S

    2010-12-01

    Engineering biosynthetic pathways to natural products is a challenging endeavor that promises to provide new therapeutics and tools to manipulate biology. Information-guided design strategies and tools could unlock the creativity of a wide spectrum of scientists and engineers by decoupling expertise from implementation.

  18. Problem Decomposition and Recomposition in Engineering Design: A Comparison of Design Behavior between Professional Engineers, Engineering Seniors, and Engineering Freshmen

    ERIC Educational Resources Information Center

    Song, Ting; Becker, Kurt; Gero, John; DeBerard, Scott; DeBerard, Oenardi; Reeve, Edward

    2016-01-01

    The authors investigated the differences in using problem decomposition and problem recomposition between dyads of engineering experts, engineering seniors, and engineering freshmen. Participants worked in dyads to complete an engineering design challenge within 1 hour. The entire design process was video and audio recorded. After the design…

  19. Testing Scientific Software: A Systematic Literature Review

    PubMed Central

    Kanewala, Upulee; Bieman, James M.

    2014-01-01

    Context Scientific software plays an important role in critical decision making, for example making weather predictions based on climate models, and computation of evidence for research publications. Recently, scientists have had to retract publications due to errors caused by software faults. Systematic testing can identify such faults in code. Objective This study aims to identify specific challenges, proposed solutions, and unsolved problems faced when testing scientific software. Method We conducted a systematic literature survey to identify and analyze relevant literature. We identified 62 studies that provided relevant information about testing scientific software. Results We found that challenges faced when testing scientific software fall into two main categories: (1) testing challenges that occur due to characteristics of scientific software such as oracle problems and (2) testing challenges that occur due to cultural differences between scientists and the software engineering community such as viewing the code and the model that it implements as inseparable entities. In addition, we identified methods to potentially overcome these challenges and their limitations. Finally we describe unsolved challenges and how software engineering researchers and practitioners can help to overcome them. Conclusions Scientific software presents special challenges for testing. Specifically, cultural differences between scientist developers and software engineers, along with the characteristics of the scientific software make testing more difficult. Existing techniques such as code clone detection can help to improve the testing process. Software engineers should consider special challenges posed by scientific software such as oracle problems when developing testing techniques. PMID:25125798

  20. A Systematic Approach for Obtaining Performance on Matrix-Like Operations

    NASA Astrophysics Data System (ADS)

    Veras, Richard Michael

    Scientific Computation provides a critical role in the scientific process because it allows us ask complex queries and test predictions that would otherwise be unfeasible to perform experimentally. Because of its power, Scientific Computing has helped drive advances in many fields ranging from Engineering and Physics to Biology and Sociology to Economics and Drug Development and even to Machine Learning and Artificial Intelligence. Common among these domains is the desire for timely computational results, thus a considerable amount of human expert effort is spent towards obtaining performance for these scientific codes. However, this is no easy task because each of these domains present their own unique set of challenges to software developers, such as domain specific operations, structurally complex data and ever-growing datasets. Compounding these problems are the myriads of constantly changing, complex and unique hardware platforms that an expert must target. Unfortunately, an expert is typically forced to reproduce their effort across multiple problem domains and hardware platforms. In this thesis, we demonstrate the automatic generation of expert level high-performance scientific codes for Dense Linear Algebra (DLA), Structured Mesh (Stencil), Sparse Linear Algebra and Graph Analytic. In particular, this thesis seeks to address the issue of obtaining performance on many complex platforms for a certain class of matrix-like operations that span across many scientific, engineering and social fields. We do this by automating a method used for obtaining high performance in DLA and extending it to structured, sparse and scale-free domains. We argue that it is through the use of the underlying structure found in the data from these domains that enables this process. Thus, obtaining performance for most operations does not occur in isolation of the data being operated on, but instead depends significantly on the structure of the data.

  1. Facilities Engineering in NASA

    NASA Technical Reports Server (NTRS)

    Pagluiso, M. A.

    1970-01-01

    An overview of NASA facilities is given outlining some of the more interesting and unique aspects of engineering and facilities associated with the space program. Outlined are some of the policies under which the Office of Facilities conducts its business. Included are environmental quality control measures.

  2. Embedded Knowledge in Transportation Engineering : Comparisons Between Engineers and Instructors

    DOT National Transportation Integrated Search

    2012-06-01

    Substantial research in a diversity of fields suggests that being successful in a skilled profession requires ways of thinking that : are unique to the context of that profession and present in practitioners of that field. Two critical concepts are s...

  3. A Case Study of a College-Wide First-Year Undergraduate Engineering Course

    ERIC Educational Resources Information Center

    Aloul, Fadi; Zualkernan, Imran; Husseini, Ghaleb; El-Hag, Ayman; Al-Assaf, Yousef

    2015-01-01

    Introductory engineering courses are either programme specific or expose students to engineering as a broad discipline by including materials from various engineering programmes. A common introductory engineering course that spans different engineering programmes raises challenges, including the high cost of resources as well as the lack of…

  4. Some Future Software Engineering Opportunities and Challenges

    NASA Astrophysics Data System (ADS)

    Boehm, Barry

    This paper provides an update and extension of a 2006 paper, “Some Future Trends and Implications for Systems and Software Engineering Processes,” Systems Engineering, Spring 2006. Some of its challenges and opportunities are similar, such as the need to simultaneously achieve high levels of both agility and assurance. Others have emerged as increasingly important, such as the challenges of dealing with ultralarge volumes of data, with multicore chips, and with software as a service. The paper is organized around eight relatively surprise-free trends and two “wild cards” whose trends and implications are harder to foresee. The eight surprise-free trends are:

  5. The Engineer Model Improvement Program Plan

    DTIC Science & Technology

    1988-08-01

    evaluations of engineer doctrine placed it in a unique position to be a focal point for USACE modeling support. To this end, on 3 December of 1986 the CC...community in a 27 February 1980 memorandum in which the Army Chief of Staff urged the Chief of Engineers "... to relook the manner in which engineers...battlefield is controlled through a system of user-established Movement-Control- Points (MCPs). An MCP is described by X-Y-Z coordinates which define a

  6. The Challenges of Career and Technical Education Concurrent Enrollment: An Administrative Perspective

    ERIC Educational Resources Information Center

    Haag, Patricia W.

    2015-01-01

    Career and technical education concurrent enrollment may pose unique challenges in programming and enrollment for program administrators, and this chapter describes the experiences and challenges of a CTE concurrent enrollment administrator.

  7. Bone Tissue Engineering: Recent Advances and Challenges

    PubMed Central

    Amini, Ami R.; Laurencin, Cato T.; Nukavarapu, Syam P.

    2013-01-01

    The worldwide incidence of bone disorders and conditions has trended steeply upward and is expected to double by 2020, especially in populations where aging is coupled with increased obesity and poor physical activity. Engineered bone tissue has been viewed as a potential alternative to the conventional use of bone grafts, due to their limitless supply and no disease transmission. However, bone tissue engineering practices have not proceeded to clinical practice due to several limitations or challenges. Bone tissue engineering aims to induce new functional bone regeneration via the synergistic combination of biomaterials, cells, and factor therapy. In this review, we discuss the fundamentals of bone tissue engineering, highlighting the current state of this field. Further, we review the recent advances of biomaterial and cell-based research, as well as approaches used to enhance bone regeneration. Specifically, we discuss widely investigated biomaterial scaffolds, micro- and nano-structural properties of these scaffolds, and the incorporation of biomimetic properties and/or growth factors. In addition, we examine various cellular approaches, including the use of mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), adult stem cells, induced pluripotent stem cells (iPSCs), and platelet-rich plasma (PRP), and their clinical application strengths and limitations. We conclude by overviewing the challenges that face the bone tissue engineering field, such as the lack of sufficient vascularization at the defect site, and the research aimed at functional bone tissue engineering. These challenges will drive future research in the field. PMID:23339648

  8. High-speed schlieren imaging of rocket exhaust plumes

    NASA Astrophysics Data System (ADS)

    Coultas-McKenney, Caralyn; Winter, Kyle; Hargather, Michael

    2016-11-01

    Experiments are conducted to examine the exhaust of a variety of rocket engines. The rocket engines are mounted in a schlieren system to allow high-speed imaging of the engine exhaust during startup, steady state, and shutdown. A variety of rocket engines are explored including a research-scale liquid rocket engine, consumer/amateur solid rocket motors, and water bottle rockets. Comparisons of the exhaust characteristics, thrust and cost for this range of rockets is presented. The variety of nozzle designs, target functions, and propellant type provides unique variations in the schlieren imaging.

  9. First Generation College Students in STEM: Counter Stories of Success

    NASA Astrophysics Data System (ADS)

    Hernandez, Carol D.

    First-generation community college Science, Technology, Engineering, and Mathematics (STEM) students have unique challenges in transferring to a four-year college. This is especially true for Latin and African American students who may experience multiple challenges, including discrimination, immigration issues and language issues, and sometimes poor academic preparation in their K-12 education. This project used a grounded theory approach to explore through an equity lens the educational journey of seven Los Medanos College students who have successfully transferred to a four-year institution were interviewed. All of these students that participated in this project were former Mathematics Engineering Science Achievement Program (MESA) students at Los Medanos College. The MESA Program is a learning community that provides academic support for "educationally and economically disadvantaged" students so they can excel in math and science, transfer to four-year institutions as majors in math-based fields, and graduate with baccalaureate degrees in STEM majors. Several intervention strategies are embedded into the program, including: counseling, mentors, a learning center, tutors, financial aid and transfer workshops, and internship and scholarship opportunities. The students were interviewed and asked several questions regarding their high school life, MESA, and community college and transfer experiences. The main theoretical framework utilized to analyze the interviews was Border Lands theory because these students created a safe space that allowed them to straddle their life at home and their life at school. Interviews with these students reveal seven successful, happy, and engaged students. Several themes emerged with respect to the importance of students' finding a major that they love, finding community, and the importance of teachers, family, and engagement in their success. The results of this project also emphasize the importance of hiring passionate teachers, challenging students, and engaging them via their interests and passions. The interviews uncovered Critical Race Theory counter stories, showing that despite the many barriers that these students encountered throughout their educational journey, they were able to succeed at the highest levels.

  10. PASSCAL Instrument Center Support for Cryoseismology: Methodologies, Challenges, Development and Instrumentation

    NASA Astrophysics Data System (ADS)

    Beaudoin, B. C.; Anderson, K. R.; Bilek, S. L.; Carpenter, P.; Childs, D.; Chung, P.; Huerta, A. D.; Lingutla, N.; Nikolaus, K.; Winberry, J. P.

    2017-12-01

    Remote portable seismic stations are, in most cases, constrained by logistics and cost. High latitude operations introduce environmental, technical and logistical challenges that require substantially more engineering work to ensure robust, high quality data return. Since 2006, IRIS PASSCAL has been funded by NSF to develop, deploy, and maintain a pool of polar specific seismic stations. At roughly the same time, PASSCAL began supporting experiments specifically targeting glacier dynamics such as the mechanisms of subglacial hydrology, basal shear stress, ice stream stick slip mechanisms, and glacier seismicity. Although much of the development for high-latitude deployments was directly applicable to cryoseismology, these new experiments introduced a unique series of challenges including high ablation, standing water, and moving stations. Our polar development objectives have focused on: Reducing station power requirements, size and weight; Extending the operational temperature of a station; Simplifying logistics; Engineering solutions that are cost effective, manufacturable, serviceable and reusable; And, developing high-latitude communications for both state-of-health and data transmission. To these ends, PASSCAL continues testing new power storage technology, refining established power systems for lighter and smaller power banks, and exploring telemetry solutions to increase high-bandwidth communication options and abilities for remote seismic stations. Further enhancing PASSCAL's ability to support cryoseismology is a recent NSF funded collaborative effort lead by Central Washing University joined by IRIS and New Mexico Tech to build a Geophysical Earth Observatory for Ice Covered Environments (GEOICE). The GEOICE instrument, power system and other integrated ancillary components are designed to require minimal installation time and logistical load (i.e., size and weight), while maximizing ease-of-use in the field and optimizing costs of instrumentation and experiment consumables. The instrument capability will include a hybrid seismograph pool of broadband and intermediate elements, for observation of both long-period and intermediate-to-short-period signals, and a high-frequency node element.

  11. AiResearch QCGAT engine, airplane, and nacelle design features

    NASA Technical Reports Server (NTRS)

    Heldenbrand, R. W.

    1980-01-01

    The quiet, clean, general aviation turbofan engine and nacelle system was designed and tested. The engine utilized the core of the AiResearch model TFE731-3 engine and incorporated several unique noise- and emissions-reduction features. Components that were successfully adapted to this core include the fan, gearbox, combustor, low-pressure turbine, and associated structure. A highly versatile workhorse nacelle incorporating interchangeable acoustic and hardwall duct liners, showed that large-engine attenuation technology could be applied to small propulsion engines. The application of the mixer compound nozzle demonstrated both performance and noise advantages on the engine. Major performance, emissions, and noise goals were demonstrated.

  12. Preparing engineers for the challenges of community engagement

    NASA Astrophysics Data System (ADS)

    Harsh, Matthew; Bernstein, Michael J.; Wetmore, Jameson; Cozzens, Susan; Woodson, Thomas; Castillo, Rafael

    2017-11-01

    Despite calls to address global challenges through community engagement, engineers are not formally prepared to engage with communities. Little research has been done on means to address this 'engagement gap' in engineering education. We examine the efficacy of an intensive, two-day Community Engagement Workshop for engineers, designed to help engineers better look beyond technology, listen to and learn from people, and empower communities. We assessed the efficacy of the workshop in a non-experimental pre-post design using a questionnaire and a concept map. Questionnaire results indicate participants came away better able to ask questions more broadly inclusive of non-technological dimensions of engineering projects. Concept map results indicate participants have a greater understanding of ways social factors shape complex material systems after completing the programme. Based on the workshop's strengths and weaknesses, we discuss the potential of expanding and supplementing the programme to help engineers account for social aspects central to engineered systems.

  13. 1000542

    NASA Image and Video Library

    2010-04-13

    HORACE STORNG (AEROSPACE ENGINEER, ER31 PROPULSION TURBOMACHINERY DESIGN & DEVELOPMENT BRANCH) ADJUSTS A UNIQUE MECHANICAL TEST SETUP THAT MEASURES STRAIN ON A SINGLE SAMPLE, USING TWO DIFFERENT TECHNIQUES AT THE SAME TIME. THE TEST FIXTURE HOLDS A SPECIMEN THAT REPRESENTS A LIQUID OXYGEN (LOX) BEARING FROM THE J2-X ENGINE

  14. 1000541

    NASA Image and Video Library

    2010-04-13

    TATHAN COFFEE (EM10 MATERIALS TEST ENGINEER, JACOBS ESTS GROUP/JTI) ADJUSTS A UNIQUE MECHANICAL TEST SETUP THAT MEASURES STRAIN ON A SINGLE SAMPLE, USING TWO DIFFERENT TECHNIQUES AT THE SAME TIME. THE TEST FIXTURE HOLDS A SPECIMEN THAT REPRESENTS A LIQUID OXYGEN (LOX) BEARING FROM THE J2-X ENGINE

  15. Heat-driven thermoacoustic cryocooler operating at liquid hydrogen temperature with a unique coupler

    NASA Astrophysics Data System (ADS)

    Hu, J. Y.; Luo, E. C.; Li, S. F.; Yu, B.; Dai, W.

    2008-05-01

    A heat-driven thermoacoustic cryocooler is constructed. A unique coupler composed of a tube, reservoir, and elastic diaphragm is introduced to couple a traveling-wave thermoacoustic engine (TE) and two-stage pulse tube refrigerator (PTR). The amplitude of the pressure wave generated in the engine is first amplified in the coupler and the wave then passes into the refrigerator to pump heat. The TE uses nitrogen as its working gas and the PTR still uses helium as its working gas. With this coupler, the efficiency of the system is doubled. The engine and coupler match at a much lower operating frequency, which is of great benefit for the PTR to obtain a lower cooling temperature. The coupling place between the coupler and engine is also optimized. The onset problem is effectively solved. With these improvements, the heat-driven thermoacoustic cryocooler reaches a lowest temperature of 18.1K, which is the demonstration of heat-driven thermoacoustic refrigeration technology used for cooling at liquid hydrogen temperatures.

  16. The MUSES Satellite Team and Multidisciplinary System Engineering

    NASA Technical Reports Server (NTRS)

    Chen, John C.; Paiz, Alfred R.; Young, Donald L.

    1997-01-01

    In a unique partnership between three minority-serving institutions and NASA's Jet Propulsion Laboratory, a new course sequence, including a multidisciplinary capstone design experience, is to be developed and implemented at each of the schools with the ambitious goal of designing, constructing and launching a low-orbit Earth-resources satellite. The three universities involved are North Carolina A&T State University (NCA&T), University of Texas, El Paso (UTEP), and California State University, Los Angeles (CSULA). The schools form a consortium collectively known as MUSES - Minority Universities System Engineering and Satellite. Four aspects of this project make it unique: (1) Including all engineering disciplines in the capstone design course, (2) designing, building and launching an Earth-resources satellite, (3) sustaining the partnership between the three schools to achieve this goal, and (4) implementing systems engineering pedagogy at each of the three schools. This paper will describe the partnership and its goals, the first design of the satellite, the courses developed at NCA&T, and the implementation plan for the course sequence.

  17. Bioencapsulation technologies in tissue engineering

    PubMed Central

    Majewski, Rebecca L.; Zhang, Wujie; Ma, Xiaojun; Cui, Zhanfeng; Ren, Weiping; Markel, David C.

    2017-01-01

    Bioencapsulation technologies have played an important role in the developing successes of tissue engineering. Besides offering immunoisolation, they also show promise for cell/tissue banking and the directed differentiation of stem cells, by providing a unique microenvironment. This review describes bioencapsulation technologies and summarizes their recent progress in research into tissue engineering. The review concludes with a brief outlook regarding future research directions in this field. PMID:27716872

  18. Effects of Single-Gender Mathematics Classrooms on Self-Perception of Mathematical Ability and Post Secondary Engineering Paths: An Australian Case Study

    ERIC Educational Resources Information Center

    Tully, D.; Jacobs, B.

    2010-01-01

    This study focused on a population of female engineering students, probing the influences of their secondary school experience on their choice to pursue an engineering course of study at university. The motivating question is: Do unique opportunities exist in an all-female secondary school mathematics classroom, which impact a young woman's…

  19. Control Engineering, System Theory and Mathematics: The Teacher's Challenge

    ERIC Educational Resources Information Center

    Zenger, K.

    2007-01-01

    The principles, difficulties and challenges in control education are discussed and compared to the similar problems in the teaching of mathematics and systems science in general. The difficulties of today's students to appreciate the classical teaching of engineering disciplines, which are based on rigorous and scientifically sound grounds, are…

  20. Sustainability: Necessity for a Prosperous Society

    ERIC Educational Resources Information Center

    Fokkema, Jacob; Jansen, Leo; Mulder, Karel

    2005-01-01

    Purpose--To present the challenge of sustainable development, the way in which technology can address that challenge and the task of engineering education to train engineers for it. Design/methodology/approach--The paper describes briefly the history of the environmental and sustainability discourse in The Netherlands, as a densely populated…

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