WorldWideScience

Sample records for technology conversely stem

  1. Induced Pluripotent Stem Cell Technology and Direct Conversion : New Possibilities to Study and Treat Parkinson's Disease

    NARCIS (Netherlands)

    Roessler, Reinhard; Boddeke, Erik; Copray, Sjef

    Recent developments in in vitro disease modeling and regenerative medicine have placed induced pluripotent stem cells (iPSCs) in the center of attention as a unique source to study Parkinson's disease. After only 5 years of intensive research, human iPSCs can be generated without viral integration

  2. Power conversion technologies

    Energy Technology Data Exchange (ETDEWEB)

    Newton, M. A.

    1997-02-01

    The Power Conversion Technologies thrust area identifies and sponsors development activities that enhance the capabilities of engineering at Lawrence Livermore National Laboratory (LLNL) in the area of solid- state power electronics. Our primary objective is to be a resource to existing and emerging LLNL programs that require advanced solid-state power electronic technologies.. Our focus is on developing and integrating technologies that will significantly impact the capability, size, cost, and reliability of future power electronic systems. During FY-96, we concentrated our research efforts on the areas of (1) Micropower Impulse Radar (MIR); (2) novel solid-state opening switches; (3) advanced modulator technology for accelerators; (4) compact accelerators; and (5) compact pulse generators.

  3. Microbial conversion technologies

    Energy Technology Data Exchange (ETDEWEB)

    Lau, P. [National Research Council of Canada, Ottawa, ON (Canada). Bioconversion and Sustainable Development

    2006-07-01

    Microbes are a biomass and an valuable resource. This presentation discussed microbial conversion technologies along with background information on microbial cells, their characteristics and microbial diversity. Untapped opportunities for microbial conversion were identified. Metagenomic and genome mining approaches were also discussed, as they can provide access to uncultivated or unculturable microorganisms in communal populations and are an unlimited resource for biocatalysts, novel genes and metabolites. Genome mining was seen as an economical approach. The presentation also emphasized that the development of microbial biorefineries would require significant insights into the relevant microorganisms and that biocatalysts were the ultimate in sustainability. In addition, the presentation discussed the natural fibres initiative for biochemicals and biomaterials. Anticipated outputs were identified and work in progress of a new enzyme-retting cocktail to provide diversity and/or consistency in fibre characteristics for various applications were also presented. It was concluded that it is necessary to leverage understanding of biological processes to produce bioproducts in a clean and sustainable manner. tabs., figs.

  4. Wavelength conversion technology

    DEFF Research Database (Denmark)

    Stubkjær, Kristian

    1998-01-01

    Optical wavelength conversion is currently attracting much interest. This is because it enables full flexibility and eases management of WDM fibre networks. The tutorial will review existing and potential application areas. Examples of node architectures and network demonstrators that use wavelen...

  5. Energy conversion and utilization technologies

    International Nuclear Information System (INIS)

    1988-01-01

    The DOE Energy Conversion and Utilization Technologies (ECUT) Program continues its efforts to expand the generic knowledge base in emerging technological areas that support energy conservation initiatives by both the DOE end-use sector programs and US private industry. ECUT addresses specific problems associated with the efficiency limits and capabilities to use alternative fuels in energy conversion and end-use. Research is aimed at understanding and improving techniques, processes, and materials that push the thermodynamic efficiency of energy conversion and usage beyond the state of the art. Research programs cover the following areas: combustion, thermal sciences, materials, catalysis and biocatalysis, and tribology. Six sections describe the status of direct contact heat exchange; the ECUT biocatalysis project; a computerized tribology information system; ceramic surface modification; simulation of internal combustion engine processes; and materials-by-design. These six sections have been indexed separately for inclusion on the database. (CK)

  6. Direct digital conversion detector technology

    Science.gov (United States)

    Mandl, William J.; Fedors, Richard

    1995-06-01

    Future imaging sensors for the aerospace and commercial video markets will depend on low cost, high speed analog-to-digital (A/D) conversion to efficiently process optical detector signals. Current A/D methods place a heavy burden on system resources, increase noise, and limit the throughput. This paper describes a unique method for incorporating A/D conversion right on the focal plane array. This concept is based on Sigma-Delta sampling, and makes optimum use of the active detector real estate. Combined with modern digital signal processors, such devices will significantly increase data rates off the focal plane. Early conversion to digital format will also decrease the signal susceptibility to noise, lowering the communications bit error rate. Computer modeling of this concept is described, along with results from several simulation runs. A potential application for direct digital conversion is also reviewed. Future uses for this technology could range from scientific instruments to remote sensors, telecommunications gear, medical diagnostic tools, and consumer products.

  7. Overview of biomass conversion technologies

    International Nuclear Information System (INIS)

    Noor, S.; Latif, A.; Jan, M.

    2011-01-01

    A large part of the biomass is used for non-commercial purposes and mostly for cooking and heating, but the use is not sustainable, because it destroys soil-nutrients, causes indoor and outdoor pollution, adds to greenhouse gases, and results in health problems. Commercial use of biomass includes household fuelwood in industrialized countries and bio-char (charcoal) and firewood in urban and industrial areas in developing countries. The most efficient way of biomass utilization is through gasification, in which the gas produced by biomass gasification can either be used to generate power in an ordinary steam-cycle or be converted into motor fuel. In the latter case, there are two alternatives, namely, the synthesis of methanol and methanol-based motor fuels, or Fischer-Tropsch hydrocarbon synthesis. This paper deals with the technological overview of the state-of-the-art key biomass-conversion technologies that can play an important role in the future. The conversion routes for production of Heat, power and transportation fuel have been summarized in this paper, viz. combustion, gasification, pyrolysis, digestion, fermentation and extraction. (author)

  8. Microturbine Power Conversion Technology Review

    Energy Technology Data Exchange (ETDEWEB)

    Staunton, R.H.

    2003-07-21

    In this study, the Oak Ridge National Laboratory (ORNL) is performing a technology review to assess the market for commercially available power electronic converters that can be used to connect microturbines to either the electric grid or local loads. The intent of the review is to facilitate an assessment of the present status of marketed power conversion technology to determine how versatile the designs are for potentially providing different services to the grid based on changes in market direction, new industry standards, and the critical needs of the local service provider. The project includes data gathering efforts and documentation of the state-of-the-art design approaches that are being used by microturbine manufacturers in their power conversion electronics development and refinement. This project task entails a review of power converters used in microturbines sized between 20 kW and 1 MW. The power converters permit microturbine generators, with their non-synchronous, high frequency output, to interface with the grid or local loads. The power converters produce 50- to 60-Hz power that can be used for local loads or, using interface electronics, synchronized for connection to the local feeder and/or microgrid. The power electronics enable operation in a stand-alone mode as a voltage source or in grid-connect mode as a current source. Some microturbines are designed to automatically switch between the two modes. The information obtained in this data gathering effort will provide a basis for determining how close the microturbine industry is to providing services such as voltage regulation, combined control of both voltage and current, fast/seamless mode transfers, enhanced reliability, reduced cost converters, reactive power supply, power quality, and other ancillary services. Some power quality improvements will require the addition of storage devices; therefore, the task should also determine what must be done to enable the power conversion circuits to

  9. Advances in wind energy conversion technology

    CERN Document Server

    Sathyajith, Mathew

    2011-01-01

    The technology of generating energy from wind has significantly changed during the past five years. The book brings together all the latest aspects of wind energy conversion technology - from wind resource analysis to grid integration of generated electricity.

  10. Advanced conversion technology review panel report

    International Nuclear Information System (INIS)

    Frazier, T.A.

    1998-01-01

    The Department of Energy (DOE), the National Aeronautics and Space Administration (NASA) and the Jet Propulsion Laboratory (JPL) established a DOE lead management team and an Advanced Conversion Technology Review Panel. The panel was tasked with providing the management team with an assessment and ranking of the three advanced conversion technologies. The three advanced conversion technologies were alkali metal thermal to electric converter (AMTEC), Stirling engine converter (SEC), and thermophotovoltaic (TPV). To rate and rank these three technologies, five criteria were developed: (1) Performance, (2) Development and Cost/Production and Cost/Schedule Risk, (3) Spacecraft Interface and Operations, (4) Ability to Scale Conversion, and (5) Safety. Discussed are the relative importance of each of these criteria and the rankings of the three advanced conversion technologies. It was the conclusion of the panel that the technology decision should be based on the risk that DOE and NASA are willing to accept. SEC is the most mature technology and would provide the lowest risk option. However, if more risk is acceptable, AMTEC not only provides benefits in the spacecraft interface but is also predicted to outperform the SEC. It was proposed that if AMTEC were selected, funding should be provided at a reasonable level to support back-up technology to be developed in a parallel fashion until AMTEC has proven its capability. The panel report and conclusion were provided to DOE in February 1997

  11. Wind Energy Conversion Systems Technology and Trends

    CERN Document Server

    2012-01-01

    Wind Energy Conversion System covers the technological progress of wind energy conversion systems, along with potential future trends. It includes recently developed wind energy conversion systems such as multi-converter operation of variable-speed wind generators, lightning protection schemes, voltage flicker mitigation and prediction schemes for advanced control of wind generators. Modeling and control strategies of variable speed wind generators are discussed, together with the frequency converter topologies suitable for grid integration. Wind Energy Conversion System also describes offshore farm technologies including multi-terminal topology and space-based wind observation schemes, as well as both AC and DC based wind farm topologies. The stability and reliability of wind farms are discussed, and grid integration issues are examined in the context of the most recent industry guidelines. Wind power smoothing, one of the big challenges for transmission system operators, is a particular focus. Fault ride th...

  12. Conversion of adult endothelium to immunocompetent haematopoietic stem cells.

    Science.gov (United States)

    Lis, Raphael; Karrasch, Charles C; Poulos, Michael G; Kunar, Balvir; Redmond, David; Duran, Jose G Barcia; Badwe, Chaitanya R; Schachterle, William; Ginsberg, Michael; Xiang, Jenny; Tabrizi, Arash Rafii; Shido, Koji; Rosenwaks, Zev; Elemento, Olivier; Speck, Nancy A; Butler, Jason M; Scandura, Joseph M; Rafii, Shahin

    2017-05-25

    Developmental pathways that orchestrate the fleeting transition of endothelial cells into haematopoietic stem cells remain undefined. Here we demonstrate a tractable approach for fully reprogramming adult mouse endothelial cells to haematopoietic stem cells (rEC-HSCs) through transient expression of the transcription-factor-encoding genes Fosb, Gfi1, Runx1, and Spi1 (collectively denoted hereafter as FGRS) and vascular-niche-derived angiocrine factors. The induction phase (days 0-8) of conversion is initiated by expression of FGRS in mature endothelial cells, which results in endogenous Runx1 expression. During the specification phase (days 8-20), RUNX1 + FGRS-transduced endothelial cells commit to a haematopoietic fate, yielding rEC-HSCs that no longer require FGRS expression. The vascular niche drives a robust self-renewal and expansion phase of rEC-HSCs (days 20-28). rEC-HSCs have a transcriptome and long-term self-renewal capacity similar to those of adult haematopoietic stem cells, and can be used for clonal engraftment and serial primary and secondary multi-lineage reconstitution, including antigen-dependent adaptive immune function. Inhibition of TGFβ and CXCR7 or activation of BMP and CXCR4 signalling enhanced generation of rEC-HSCs. Pluripotency-independent conversion of endothelial cells into autologous authentic engraftable haematopoietic stem cells could aid treatment of haematological disorders.

  13. Energy technology sources, systems and frontier conversion

    CERN Document Server

    Ohta, Tokio

    1994-01-01

    This book provides a concise and technical overview of energy technology: the sources of energy, energy systems and frontier conversion. As well as serving as a basic reference book for professional scientists and students of energy, it is intended for scientists and policy makers in other disciplines (including practising engineers, biologists, physicists, economists and managers in energy related industries) who need an up-to-date and authoritative guide to the field of energy technology.Energy systems and their elemental technologies are introduced and evaluated from the view point

  14. Symposium Promotes Technological Literacy through STEM

    Science.gov (United States)

    Havice, Bill; Marshall, Jerry

    2009-01-01

    This article describes a symposium which promotes technological literacy through science, technology, engineering, and mathematics (STEM). The three-day symposium titled, "The Anderson, Oconee, Pickens Symposium on Teaching and Learning STEM Standards for the 21st Century," was held August 4-6, 2008 at the Tri-County Technical College…

  15. Energy conversion technology by chemical processes

    Energy Technology Data Exchange (ETDEWEB)

    Oh, I W; Yoon, K S; Cho, B W [Korea Inst. of Science and Technology, Seoul (Korea, Republic of); and others

    1996-12-01

    The sharp increase in energy usage according to the industry development has resulted in deficiency of energy resources and severe pollution problems. Therefore, development of the effective way of energy usage and energy resources of low pollution is needed. Development of the energy conversion technology by chemical processes is also indispensable, which will replace the pollutant-producing and inefficient mechanical energy conversion technologies. Energy conversion technology by chemical processes directly converts chemical energy to electrical one, or converts heat energy to chemical one followed by heat storage. The technology includes batteries, fuel cells, and energy storage system. The are still many problems on performance, safety, and manufacturing of the secondary battery which is highly demanded in electronics, communication, and computer industries. To overcome these problems, key components such as carbon electrode, metal oxide electrode, and solid polymer electrolyte are developed in this study, followed by the fabrication of the lithium secondary battery. Polymer electrolyte fuel cell, as an advanced power generating apparatus with high efficiency, no pollution, and no noise, has many applications such as zero-emission vehicles, on-site power plants, and military purposes. After fabricating the cell components and operating the single cells, the fundamental technologies in polymer electrolyte fuel cell are established in this study. Energy storage technology provides the safe and regular heat energy, irrespective of the change of the heat energy sources, adjusts time gap between consumption and supply, and upgrades and concentrates low grade heat energy. In this study, useful chemical reactions for efficient storage and transport are investigated and the chemical heat storage technology are developed. (author) 41 refs., 90 figs., 20 tabs.

  16. Biomass energy conversion: conventional and advanced technologies

    Energy Technology Data Exchange (ETDEWEB)

    Young, B C; Hauserman, W B [Energy and Environmental Research Center, University of North Dakota, Grand Forks, ND (United States)

    1995-12-01

    Increasing interest in biomass energy conversion in recent years has focused attention on enhancing the efficiency of technologies converting biomass fuels into heat and power, their capital and operating costs and their environmental emissions. Conventional combustion systems, such as fixed-bed or grate units and entrainment units, deliver lower efficiencies (<25%) than modem coal-fired combustors (30-35%). The gasification of biomass will improve energy conversion efficiency and yield products useful for heat and power generation and chemical synthesis. Advanced biomass gasification technologies using pressurized fluidized-bed systems, including those incorporating hot-gas clean-up for feeding gas turbines or fuel cells, are being demonstrated. However, many biomass gasification processes are derivatives of coal gasification technologies and do not exploit the unique properties of biomass. This paper examines some existing and upcoming technologies for converting biomass into electric power or heat. Small-scale 1-30 MWe units are emphasized, but brief reference is made to larger and smaller systems, including those that bum coal-biomass mixtures and gasifiers that feed pilot-fuelled diesel engines. Promising advanced systems, such as a biomass integrated gasifier/gas turbine (BIG/GT) with combined-cycle operation and a biomass gasifier coupled to a fuel cell, giving cycle efficiencies approaching 50% are also described. These advanced gasifiers, typically fluid-bed designs, may be pressurized and can use a wide variety of biomass materials to generate electricity, process steam and chemical products such as methanol. Low-cost, disposable catalysts are becoming available for hot-gas clean-up (enhanced gas composition) for turbine and fuel cell systems. The advantages, limitations and relative costs of various biomass gasifier systems are briefly discussed. The paper identifies the best known biomass power projects and includes some information on proposed and

  17. Biomass energy conversion: conventional and advanced technologies

    International Nuclear Information System (INIS)

    Young, B.C.; Hauserman, W.B.

    1995-01-01

    Increasing interest in biomass energy conversion in recent years has focused attention on enhancing the efficiency of technologies converting biomass fuels into heat and power, their capital and operating costs and their environmental emissions. Conventional combustion systems, such as fixed-bed or grate units and entrainment units, deliver lower efficiencies (<25%) than modem coal-fired combustors (30-35%). The gasification of biomass will improve energy conversion efficiency and yield products useful for heat and power generation and chemical synthesis. Advanced biomass gasification technologies using pressurized fluidized-bed systems, including those incorporating hot-gas clean-up for feeding gas turbines or fuel cells, are being demonstrated. However, many biomass gasification processes are derivatives of coal gasification technologies and do not exploit the unique properties of biomass. This paper examines some existing and upcoming technologies for converting biomass into electric power or heat. Small-scale 1-30 MWe units are emphasized, but brief reference is made to larger and smaller systems, including those that bum coal-biomass mixtures and gasifiers that feed pilot-fuelled diesel engines. Promising advanced systems, such as a biomass integrated gasifier/gas turbine (BIG/GT) with combined-cycle operation and a biomass gasifier coupled to a fuel cell, giving cycle efficiencies approaching 50% are also described. These advanced gasifiers, typically fluid-bed designs, may be pressurized and can use a wide variety of biomass materials to generate electricity, process steam and chemical products such as methanol. Low-cost, disposable catalysts are becoming available for hot-gas clean-up (enhanced gas composition) for turbine and fuel cell systems. The advantages, limitations and relative costs of various biomass gasifier systems are briefly discussed. The paper identifies the best known biomass power projects and includes some information on proposed and

  18. Technology advancement for integrative stem cell analyses.

    Science.gov (United States)

    Jeong, Yoon; Choi, Jonghoon; Lee, Kwan Hyi

    2014-12-01

    Scientists have endeavored to use stem cells for a variety of applications ranging from basic science research to translational medicine. Population-based characterization of such stem cells, while providing an important foundation to further development, often disregard the heterogeneity inherent among individual constituents within a given population. The population-based analysis and characterization of stem cells and the problems associated with such a blanket approach only underscore the need for the development of new analytical technology. In this article, we review current stem cell analytical technologies, along with the advantages and disadvantages of each, followed by applications of these technologies in the field of stem cells. Furthermore, while recent advances in micro/nano technology have led to a growth in the stem cell analytical field, underlying architectural concepts allow only for a vertical analytical approach, in which different desirable parameters are obtained from multiple individual experiments and there are many technical challenges that limit vertically integrated analytical tools. Therefore, we propose--by introducing a concept of vertical and horizontal approach--that there is the need of adequate methods to the integration of information, such that multiple descriptive parameters from a stem cell can be obtained from a single experiment.

  19. Technology assessment of wind energy conversion systems

    Energy Technology Data Exchange (ETDEWEB)

    Meier, B. W.; Merson, T. J.

    1980-09-01

    Environmental data for wind energy conversion systems (WECSs) have been generated in support of the Technology Assessment of Solar Energy (TASE) program. Two candidates have been chosen to characterize the WECS that might be deployed if this technology makes a significant contribution to the national energy requirements. One WECS is a large machine of 1.5-MW-rated capacity that can be used by utilities. The other WECS is a small machine that is characteristic of units that might be used to meet residential or small business energy requirements. Energy storage systems are discussed for each machine to address the intermittent nature of wind power. Many types of WECSs are being studied and a brief review of the technology is included to give background for choosing horizontal axis designs for this study. Cost estimates have been made for both large and small systems as required for input to the Strategic Environmental Assessment Simulation (SEAS) computer program. Material requirements, based on current generation WECSs, are discussed and a general discussion of environmental impacts associated with WECS deployment is presented.

  20. The Nature of Primary Students' Conversation in Technology Education

    Science.gov (United States)

    Fox-Turnbull, Wendy H.

    2016-01-01

    Classroom conversations are core to establishing successful learning for students. This research explores the nature of conversation in technology education in the primary classroom and the implications for teaching and learning. Over a year, two units of work in technology were taught in two primary classrooms. Most data was gathered in Round 2…

  1. Neural Conversion and Patterning of Human Pluripotent Stem Cells: A Developmental Perspective.

    Science.gov (United States)

    Zirra, Alexandra; Wiethoff, Sarah; Patani, Rickie

    2016-01-01

    Since the reprogramming of adult human terminally differentiated somatic cells into induced pluripotent stem cells (hiPSCs) became a reality in 2007, only eight years have passed. Yet over this relatively short period, myriad experiments have revolutionized previous stem cell dogmata. The tremendous promise of hiPSC technology for regenerative medicine has fuelled rising expectations from both the public and scientific communities alike. In order to effectively harness hiPSCs to uncover fundamental mechanisms of disease, it is imperative to first understand the developmental neurobiology underpinning their lineage restriction choices in order to predictably manipulate cell fate to desired derivatives. Significant progress in developmental biology provides an invaluable resource for rationalising directed differentiation of hiPSCs to cellular derivatives of the nervous system. In this paper we begin by reviewing core developmental concepts underlying neural induction in order to provide context for how such insights have guided reductionist in vitro models of neural conversion from hiPSCs. We then discuss early factors relevant in neural patterning, again drawing upon crucial knowledge gained from developmental neurobiological studies. We conclude by discussing open questions relating to these concepts and how their resolution might serve to strengthen the promise of pluripotent stem cells in regenerative medicine.

  2. Neural Conversion and Patterning of Human Pluripotent Stem Cells: A Developmental Perspective

    Directory of Open Access Journals (Sweden)

    Alexandra Zirra

    2016-01-01

    Full Text Available Since the reprogramming of adult human terminally differentiated somatic cells into induced pluripotent stem cells (hiPSCs became a reality in 2007, only eight years have passed. Yet over this relatively short period, myriad experiments have revolutionized previous stem cell dogmata. The tremendous promise of hiPSC technology for regenerative medicine has fuelled rising expectations from both the public and scientific communities alike. In order to effectively harness hiPSCs to uncover fundamental mechanisms of disease, it is imperative to first understand the developmental neurobiology underpinning their lineage restriction choices in order to predictably manipulate cell fate to desired derivatives. Significant progress in developmental biology provides an invaluable resource for rationalising directed differentiation of hiPSCs to cellular derivatives of the nervous system. In this paper we begin by reviewing core developmental concepts underlying neural induction in order to provide context for how such insights have guided reductionist in vitro models of neural conversion from hiPSCs. We then discuss early factors relevant in neural patterning, again drawing upon crucial knowledge gained from developmental neurobiological studies. We conclude by discussing open questions relating to these concepts and how their resolution might serve to strengthen the promise of pluripotent stem cells in regenerative medicine.

  3. Hollywood's Conversion to Color: The Technological, Economic and Aesthetic Factors.

    Science.gov (United States)

    Kindem, Forham A.

    1979-01-01

    Discusses the film industry's conversion to color cinematography in the period between the 1920s and 1960s. Cites economic considerations, technological modifications, and aesthetic preferences by audiences as factors in this development. (JMF)

  4. STEM and Technology Education: International State-of-the-Art

    Science.gov (United States)

    Ritz, John M.; Fan, Szu-Chun

    2015-01-01

    This paper reports the perceptions of 20 international technology education scholars on their country's involvement in science, technology, engineering, and mathematics (STEM) education. Survey research was used to obtain data. It was found that the concept of STEM education is being discussed differently by nations. Some consider STEM education…

  5. Advanced Radioisotope Power Conversion Technology Research and Development

    Science.gov (United States)

    Wong, Wayne A.

    2004-01-01

    NASA's Radioisotope Power Conversion Technology program is developing next generation power conversion technologies that will enable future missions that have requirements that cannot be met by either the ubiquitous photovoltaic systems or by current Radioisotope Power System (RPS) technology. Performance goals of advanced radioisotope power systems include improvement over the state-of-practice General Purpose Heat Source/Radioisotope Thermoelectric Generator by providing significantly higher efficiency to reduce the number of radioisotope fuel modules, and increase specific power (watts/kilogram). Other Advanced RPS goals include safety, long-life, reliability, scalability, multi-mission capability, resistance to radiation, and minimal interference with the scientific payload. NASA has awarded ten contracts in the technology areas of Brayton, Stirling, Thermoelectric, and Thermophotovoltaic power conversion including five development contracts that deal with more mature technologies and five research contracts. The Advanced RPS Systems Assessment Team includes members from NASA GRC, JPL, DOE and Orbital Sciences whose function is to review the technologies being developed under the ten Radioisotope Power Conversion Technology contracts and assess their relevance to NASA's future missions. Presented is an overview of the ten radioisotope power conversion technology contracts and NASA's Advanced RPS Systems Assessment Team.

  6. Renewable energy systems advanced conversion technologies and applications

    CERN Document Server

    Luo, Fang Lin

    2012-01-01

    Energy conversion techniques are key in power electronics and even more so in renewable energy source systems, which require a large number of converters. Renewable Energy Systems: Advanced Conversion Technologies and Applications describes advanced conversion technologies and provides design examples of converters and inverters for renewable energy systems-including wind turbine and solar panel energy systems. Learn Cutting-Edge Techniques for Converters and Inverters Setting the scene, the book begins with a review of the basics of astronomy and Earth physics. It then systematically introduc

  7. Emerging electrochemical energy conversion and storage technologies

    Science.gov (United States)

    Badwal, Sukhvinder P. S.; Giddey, Sarbjit S.; Munnings, Christopher; Bhatt, Anand I.; Hollenkamp, Anthony F.

    2014-01-01

    Electrochemical cells and systems play a key role in a wide range of industry sectors. These devices are critical enabling technologies for renewable energy; energy management, conservation, and storage; pollution control/monitoring; and greenhouse gas reduction. A large number of electrochemical energy technologies have been developed in the past. These systems continue to be optimized in terms of cost, life time, and performance, leading to their continued expansion into existing and emerging market sectors. The more established technologies such as deep-cycle batteries and sensors are being joined by emerging technologies such as fuel cells, large format lithium-ion batteries, electrochemical reactors; ion transport membranes and supercapacitors. This growing demand (multi billion dollars) for electrochemical energy systems along with the increasing maturity of a number of technologies is having a significant effect on the global research and development effort which is increasing in both in size and depth. A number of new technologies, which will have substantial impact on the environment and the way we produce and utilize energy, are under development. This paper presents an overview of several emerging electrochemical energy technologies along with a discussion some of the key technical challenges. PMID:25309898

  8. Deep conversion of black oils with Eni Slurry technology

    Energy Technology Data Exchange (ETDEWEB)

    Panariti, Nicoletta; Rispoli, Giacomo

    2010-09-15

    Eni Slurry Technology represents a significant technological innovation in residue conversion and unconventional oils upgrading. EST allows the almost total conversion of heavy feedstocks into useful products, mainly transportation fuels, with a great major impact on the economic and environmental valorization of hydrocarbon resources. The peculiar characteristics of EST in terms of yields, products quality, absence of undesired by-products and feedstock flexibility constitute its superior economic and environmental attractiveness. The first full scale industrial plant based on this new technology will be realized in Eni's Sannazzaro refinery (23,000 bpd). Oil in is scheduled by 4th quarter 2012.

  9. Plasma technology - a novel solution for CO2 conversion?

    Science.gov (United States)

    Snoeckx, Ramses; Bogaerts, Annemie

    2017-10-02

    CO 2 conversion into value-added chemicals and fuels is considered as one of the great challenges of the 21st century. Due to the limitations of the traditional thermal approaches, several novel technologies are being developed. One promising approach in this field, which has received little attention to date, is plasma technology. Its advantages include mild operating conditions, easy upscaling, and gas activation by energetic electrons instead of heat. This allows thermodynamically difficult reactions, such as CO 2 splitting and the dry reformation of methane, to occur with reasonable energy cost. In this review, after exploring the traditional thermal approaches, we have provided a brief overview of the fierce competition between various novel approaches in a quest to find the most effective and efficient CO 2 conversion technology. This is needed to critically assess whether plasma technology can be successful in an already crowded arena. The following questions need to be answered in this regard: are there key advantages to using plasma technology over other novel approaches, and if so, what is the flip side to the use of this technology? Can plasma technology be successful on its own, or can synergies be achieved by combining it with other technologies? To answer these specific questions and to evaluate the potentials and limitations of plasma technology in general, this review presents the current state-of-the-art and a critical assessment of plasma-based CO 2 conversion, as well as the future challenges for its practical implementation.

  10. Review of Biojet Fuel Conversion Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei-Cheng [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tao, Ling [National Renewable Energy Lab. (NREL), Golden, CO (United States); Markham, Jennifer [National Renewable Energy Lab. (NREL), Golden, CO (United States); Zhang, Yanan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tan, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Batan, Liaw [National Renewable Energy Lab. (NREL), Golden, CO (United States); Warner, Ethan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Biddy, Mary [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-07-01

    Biomass-derived jet (biojet) fuel has become a key element in the aviation industry’s strategy to reduce operating costs and environmental impacts. Researchers from the oil-refining industry, the aviation industry, government, biofuel companies, agricultural organizations, and academia are working toward developing commercially viable and sustainable processes that produce long-lasting renewable jet fuels with low production costs and low greenhouse gas emissions. Additionally, jet fuels must meet ASTM International specifications and potentially be a 100% drop-in replacement for the current petroleum jet fuel. The combustion characteristics and engine tests demonstrate the benefits of running the aviation gas turbine with biojet fuels. In this study, the current technologies for producing renewable jet fuels, categorized by alcohols-to-jet, oil-to-jet, syngas-to-jet, and sugar-to-jet pathways, are reviewed. The main challenges for each technology pathway, including feedstock availability, conceptual process design, process economics, life-cycle assessment of greenhouse gas emissions, and commercial readiness, are discussed. Although the feedstock price and availability and energy intensity of the process are significant barriers, biomass-derived jet fuel has the potential to replace a significant portion of conventional jet fuel required to meet commercial and military demand.

  11. Biological Conversion of Sugars to Hydrocarbons Technology Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Ryan; Biddy, Mary J.; Tan, Eric; Tao, Ling; Jones, Susanne B.

    2013-03-31

    In support of the Bioenergy Technologies Office, the National Renewable Energy Laboratory (NREL) and the Pacific Northwest National Laboratory (PNNL) are undertaking studies of biomass conversion technologies to identify barriers and target research toward reducing conversion costs. Process designs and preliminary economic estimates for each of these pathway cases were developed using rigorous modeling tools (Aspen Plus and Chemcad). These analyses incorporated the best information available at the time of development, including data from recent pilot and bench-scale demonstrations, collaborative industrial and academic partners, and published literature and patents. This technology pathway case investigates the biological conversion of biomass derived sugars to hydrocarbon biofuels, utilizing data from recent literature references and information consistent with recent pilot scale demonstrations at NREL. Technical barriers and key research needs have been identified that should be pursued for the pathway to become competitive with petroleum-derived gasoline, diesel and jet range hydrocarbon blendstocks.

  12. Assessment of leaf/stem ratio in wheat straw feedstock and impact on enzymatic conversion

    DEFF Research Database (Denmark)

    Zhang, Heng; Fangel, Jonatan Ulrik; Willats, William George Tycho

    2014-01-01

    . By preparing samples of various leaf-to-stem (L/S) ratios, we found shifting conversion behavior as processing parameters were modified. Increasing the enzyme dosage, pretreatment temperature and pretreatment time all significantly improved conversion rates in samples with more than 50% leaf content, whereas...... less impact was observed on samples with less than 50% leaf content. Enzyme affinity, desorption and readsorption with leaf and stem fractions may affect the sugar yield in wheat straw saccharification. The data suggest that the L/S ratio is an important parameter when adjusting or optimizing...... conversion processes and additionally in feedstock breeding. Furthermore, this highlights the need for rapid techniques for determining L/S ratio in wheat straw harvests. The CoMPP data on specific carbohydrates and leaf pectin highlight carbohydrate epitopes that may be useful as markers in the development...

  13. Immersive STEM: From Fulldome to VR Technologies

    Science.gov (United States)

    Wyatt, R. J.

    2015-12-01

    For more than 15 years, fulldome video technology has transformed planetariums worldwide, using data-driven visualizations to support science storytelling. Fulldome video shares significant technical infrastructure with emerging VR headset technologies, and these personalized VR experiences allow for new audiences and new experiences of an existing library of context—as well as affording new opportunities for fulldome producers to explore. At the California Academy of Sciences, we are translating assets for our planetarium shows into immersive experiences for a variety of HR headsets. We have adapted scenes from our four award-wining features—Fragile Planet (2008), Life: A Cosmic Story (2010), Earthquake: Evidence of a Restless Planet (2012), and Habitat Earth (2015)—to place viewers inside a virtual planetarium viewing the shows. Similarly, we have released two creative-commons mini-shows on various VR outlets. This presentation will also highlight content the Academy will make available from our upcoming 2016 planetarium show about asteroids, comets, and solar system origins, some of which has been formatted for a full four-pi-steradian perspective. The shared immersive environment of digital planetariums offers significant opportunities for education and affective engagement of STEM-hungry audiences—including students, families, and adults. With the advent of VR technologies, we can leverage the experience of fulldome producers and planetarium professionals to create personalized home experiences that allow new ways to experience their content.

  14. Biological Conversion of Sugars to Hydrocarbons Technology Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Davis, R.; Biddy, M.; Tan, E.; Tao, L.; Jones, S.

    2013-03-01

    This technology pathway case investigates the biological conversion of biomass-derived sugars to hydrocarbon biofuels, utilizing data from recent literature references and information consistent with recent pilot-scale demonstrations at NREL. Technical barriers and key research needs have been identified that should be pursued for the pathway to become competitive with petroleum-derived gasoline-, diesel-, and jet-range hydrocarbon blendstocks.

  15. Genome editing: a robust technology for human stem cells.

    Science.gov (United States)

    Chandrasekaran, Arun Pandian; Song, Minjung; Ramakrishna, Suresh

    2017-09-01

    Human pluripotent stem cells comprise induced pluripotent and embryonic stem cells, which have tremendous potential for biological and therapeutic applications. The development of efficient technologies for the targeted genome alteration of stem cells in disease models is a prerequisite for utilizing stem cells to their full potential. Genome editing of stem cells is possible with the help of synthetic nucleases that facilitate site-specific modification of a gene of interest. Recent advances in genome editing techniques have improved the efficiency and speed of the development of stem cells for human disease models. Zinc finger nucleases, transcription activator-like effector nucleases, and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated system are powerful tools for editing DNA at specific loci. Here, we discuss recent technological advances in genome editing with site-specific nucleases in human stem cells.

  16. Electrochemical conversion technologies for optimal design of decentralized multi-energy systems : Modeling framework and technology assessment

    NARCIS (Netherlands)

    Gabrielli, Paolo; Gazzani, Matteo; Mazzotti, Marco

    2018-01-01

    The design and operation of integrated multi-energy systems require models that adequately describe the behavior of conversion and storage technologies. Typically, linear conversion performance or fixed data from technology manufacturers are employed, especially for new or advanced technologies.

  17. New Advanced Technologies in Stem Cell Therapy

    Science.gov (United States)

    2014-11-01

    James, J. N. Zara , M. Corselli et al., “An abundant perivascular source of stem cells for bone tissue engineering,” Stem Cells Translational Medicine...vol. 1, no. 9, pp. 673–684, 2012. [89] A.W. James, J. N. Zara , X. Zhang et al., “Perivascular stem cells: a prospectively purified mesenchymal stem...1, pp. 54–63, 2009. [176] A. Askarinam, A. W. James, J. N. Zara et al., “Human perivas- cular stem cells show enhanced osteogenesis and

  18. Development of New Technologies for Stem Cell Research

    Directory of Open Access Journals (Sweden)

    Xibo Ma

    2012-01-01

    Full Text Available Since the 1960s, the stem cells have been extensively studied including embryonic stem cells, neural stem cells, bone marrow hematopoietic stem cells, and mesenchymal stem cells. In the recent years, several stem cells have been initially used in the treatment of diseases, such as in bone marrow transplant. At the same time, isolation and culture experimental technologies for stem cell research have been widely developed in recent years. In addition, molecular imaging technologies including optical molecular imaging, positron emission tomography, single-photon emission computed tomography, and computed tomography have been developed rapidly in recent the 10 years and have also been used in the research on disease mechanism and evaluation of treatment of disease related with stem cells. This paper will focus on recent typical isolation, culture, and observation techniques of stem cells followed by a concise introduction. Finally, the current challenges and the future applications of the new technologies in stem cells are given according to the understanding of the authors, and the paper is then concluded.

  19. Stem cell technology for drug discovery and development.

    Science.gov (United States)

    Hook, Lilian A

    2012-04-01

    Stem cells have enormous potential to revolutionise the drug discovery process at all stages, from target identification through to toxicology studies. Their ability to generate physiologically relevant cells in limitless supply makes them an attractive alternative to currently used recombinant cell lines or primary cells. However, realisation of the full potential of stem cells is currently hampered by the difficulty in routinely directing stem cell differentiation to reproducibly and cost effectively generate pure populations of specific cell types. In this article we discuss how stem cells have already been used in the drug discovery process and how novel technologies, particularly in relation to stem cell differentiation, can be applied to attain widespread adoption of stem cell technology by the pharmaceutical industry. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Technology and Teaching: A Conversation among Faculty Regarding the Pros and Cons of Technology

    Science.gov (United States)

    Kemp, Andrew T.; Preston, John; Page, C. Steven; Harper, Rebecca; Dillard, Benita; Flynn, Joseph; Yamaguchi, Misato

    2014-01-01

    Technology is often touted as the savior of education (Collins & Haverson, 2009). However, is technology the panacea that it is made out to be? This paper is an extended conversation among a group of faculty members at three different universities and their attitudes and beliefs about technology and education. Three professors shared their…

  1. Assessment of tidal and wave energy conversion technologies in Canada

    International Nuclear Information System (INIS)

    2009-01-01

    This paper presented an attractive option to help meet Canada's future energy needs, notably the vast and energetic Atlantic, Pacific and Arctic coastal waters which make ocean renewable energy, particularly tidal in-stream energy conversion (TISEC) and wave energy conversion (WEC). There is much uncertainty regarding the possible environmental impacts associated with their deployment and operation. In support of commercial development of the industry, a review of scientific knowledge was needed for the development of policy and regulations consistent with Canada's conservation and sustainability priorities. In April 2009, Fisheries and Oceans Canada (DFO) hosted a two-day national science advisory process meeting in order to determine the current state of knowledge on the environmental impacts of tidal and wave energy conversion technologies and their application in the Canadian context based on published reports. Potential mitigation measures were identified and the feasibility of developing a relevant Canadian statement of practice was determined. This report presented an assessment and analysis of wave power, including the impacts on physical processes; impacts on habitat characteristics; impacts on water quality; impacts of noise and vibrations; impacts of electromagnetic fields; impacts of physical encounters; cumulative impacts; and mitigation measures. It was concluded that there is a recognized need to develop and maintain national and regional georeferenced, interoperable, standards-based databases that enable access by governments, developers, academics, non-governmental organizations and the general public. 1 ref., 1 fig.

  2. Integrated STEM: A New Primer for Teaching Technology Education

    Science.gov (United States)

    Asunda, Paul A.; Mativo, John

    2017-01-01

    Part One of this article ("Technology and Engineering Teacher," 75(4), December/January, 2016) presented a process that science, math, engineering, and technology teachers could use to collaborate and design integrated STEM courses. A conceptual framework was discussed that could provide a premise that educators interested in delivery of…

  3. Stem cells technology: a powerful tool behind new brain treatments.

    Science.gov (United States)

    Duru, Lucienne N; Quan, Zhenzhen; Qazi, Talal Jamil; Qing, Hong

    2018-06-18

    Stem cell research has recently become a hot research topic in biomedical research due to the foreseen unlimited potential of stem cells in tissue engineering and regenerative medicine. For many years, medicine has been facing intense challenges, such as an insufficient number of organ donations that is preventing clinicians to fulfill the increasing needs. To try and overcome this regrettable matter, research has been aiming at developing strategies to facilitate the in vitro culture and study of stem cells as a tool for tissue regeneration. Meanwhile, new developments in the microfluidics technology brought forward emerging cell culture applications that are currently allowing for a better chemical and physical control of cellular microenvironment. This review presents the latest developments in stem cell research that brought new therapies to the clinics and how the convergence of the microfluidics technology with stem cell research can have positive outcomes on the fields of regenerative medicine and high-throughput screening. These advances will bring new translational solutions for drug discovery and will upgrade in vitro cell culture to a new level of accuracy and performance. We hope this review will provide new insights into the understanding of new brain treatments from the perspective of stem cell technology especially regarding regenerative medicine and tissue engineering.

  4. Aging of the skeletal muscle extracellular matrix drives a stem cell fibrogenic conversion.

    Science.gov (United States)

    Stearns-Reider, Kristen M; D'Amore, Antonio; Beezhold, Kevin; Rothrauff, Benjamin; Cavalli, Loredana; Wagner, William R; Vorp, David A; Tsamis, Alkiviadis; Shinde, Sunita; Zhang, Changqing; Barchowsky, Aaron; Rando, Thomas A; Tuan, Rocky S; Ambrosio, Fabrisia

    2017-06-01

    Age-related declines in skeletal muscle regeneration have been attributed to muscle stem cell (MuSC) dysfunction. Aged MuSCs display a fibrogenic conversion, leading to fibrosis and impaired recovery after injury. Although studies have demonstrated the influence of in vitro substrate characteristics on stem cell fate, whether and how aging of the extracellular matrix (ECM) affects stem cell behavior has not been investigated. Here, we investigated the direct effect of the aged muscle ECM on MuSC lineage specification. Quantification of ECM topology and muscle mechanical properties reveals decreased collagen tortuosity and muscle stiffening with increasing age. Age-related ECM alterations directly disrupt MuSC responses, and MuSCs seeded ex vivo onto decellularized ECM constructs derived from aged muscle display increased expression of fibrogenic markers and decreased myogenicity, compared to MuSCs seeded onto young ECM. This fibrogenic conversion is recapitulated in vitro when MuSCs are seeded directly onto matrices elaborated by aged fibroblasts. When compared to young fibroblasts, fibroblasts isolated from aged muscle display increased nuclear levels of the mechanosensors, Yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding motif (TAZ), consistent with exposure to a stiff microenvironment in vivo. Accordingly, preconditioning of young fibroblasts by seeding them onto a substrate engineered to mimic the stiffness of aged muscle increases YAP/TAZ nuclear translocation and promotes secretion of a matrix that favors MuSC fibrogenesis. The findings here suggest that an age-related increase in muscle stiffness drives YAP/TAZ-mediated pathogenic expression of matricellular proteins by fibroblasts, ultimately disrupting MuSC fate. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  5. Foresight Study on Advanced Conversion Technologies of Fossil Fuels

    International Nuclear Information System (INIS)

    Claver, A.; Cabrera, J. A.

    2000-01-01

    The Observatorio de Prospectiva Tecnologica Industrial (OPTI) is a Foundation supported by the Ministry of Industry and Energy, (MINER) and has as main objective to provide a basic information and knowledge on technology evolution. This information will be accessible to the Administration and to the Companies and can be taking into account in planning and decision making of technology policies. Ciemat is member of OPTI and is the organism in charge of the actions in the Energy sector. CIEMAT has the responsibility on the realisation of the sector studies to get in three years (1998 to 2001) a foresight vision of the critical technology topics. The OPTI integrated strategic plan undertake the analysis of other seven technology sectors, with the same criteria on methodological aspects. Delphi method was used for the realization of the studies. It consisted of a survey conducted in two rounds using a questionnaire to check the experts opinion. The time frame of the studies was defined from 1999 to 2015. The study presented in this document has been performed by CIEMAT in the second stage of the OPTI activities. The main goal behind this study is to identify the advanced clean and efficient technologies for the conversion of fossil fuels to promote in our country. The questionnaire was addressed to 250 experts and the response rate was about the 37%, ratifying the final results. The spanish position and the barriers for the development of each technology has been determined and also the recommended measures to facilitate their performance in the future. This basic information is consider of main interest, taking in account the actual energetic situation with a foreseeable demand increase and fossil fuels dependence. (Author) 17 refs

  6. Symposium proceedings: environmental aspects of fuel conversion technology, II, December 1975, Hollywood, Florida. [34 papers

    Energy Technology Data Exchange (ETDEWEB)

    Ayer, F.A. (comp.)

    1976-06-01

    The report covers EPA's second symposium on the environmental aspects of fuel conversion technology. Its main objective was to review and discuss environmentally related information in the field of fuel conversion technology. Specific topics were environmental problem definition, process technology, control technology, and process measurements. Thirty-four papers were abstracted and indexed separately.

  7. Low-cost feedstock conversion to biodiesel via ultrasound technology

    Energy Technology Data Exchange (ETDEWEB)

    Babajide, O.; Petrik, L.; Amigun, B.; Ameer, F. [Environmental and Nano Science Research Group, Department of Chemistry, University of the Western Cape, Bellville, Cape Town 7535 (South Africa); Amigun, B. [Sustainable Energy Futures, Council for Scientific and Industrial Research (CSIR), Stellenbosch (South Africa)

    2010-10-15

    Biodiesel has attracted increasing interest and has proved to be a good substitute for fossil-based fuels due to its environmental advantages and availability from renewable resources such as refined and waste vegetable oils. Several studies have shown that biodiesel is a better fuel than the fossil-derived diesel in terms of engine performance, emissions reduction, lubricity and environmental benefits. The increasing popularity of biodiesel has generated great demand for its commercial production methods, which in turn calls for the development of technically and economically sound process technologies. This paper explores the applicability of ultrasound in the optimization of low-cost feedstock - in this case waste cooking oil - in the transesterification conversion to biodiesel. It was found that the conversion efficiency of the waste oil using ultrasound was higher than with the mechanical stirring method. The optimized variables of 6:1 methanol/oil ratio at a reaction temperature of 30 {sup o}C, a reaction time of 30 min and 0.75% KOH (wt/wt) catalyst concentration were obtained for the transesterification of the waste oil via the use of ultrasound. (authors)

  8. Low-Cost Feedstock Conversion to Biodiesel via Ultrasound Technology

    Energy Technology Data Exchange (ETDEWEB)

    Babajide, Omotola [Environmental and Nano Science Research Group, Dept. of Chemistry, Univ. of the Western Cape, Bellville, Cape Town (South Africa); Petrik, Leslie [Environmental and Nano Science Research Group, Dept. of Chemistry, Univ. of the Western Cape, Bellville, Cape Town (South Africa); Amigun, Bamikole [Environmental and Nano Science Research Group, Dept. of Chemistry, Univ. of the Western Cape, Bellville, Cape Town (South Africa) and Sustainable Energy Futures, Council for Scientific and Industrial Research (CSIR), Stellenbosch (South Africa); Ameer, Faraouk [Environmental and Nano Science Research Group, Dept. of Chemistry, Univ. of the Western Cape, Bellville, Cape Town (South Africa)

    2010-09-15

    Biodiesel has attracted increasing interest and has proved to be a good substitute for fossil-based fuels due to its environmental advantages and availability from renewable resources such as refined and waste vegetable oils. Several studies have shown that biodiesel is a better fuel than the fossil-derived diesel in terms of engine performance, emissions reduction, lubricity and environmental benefits. The increasing popularity of biodiesel has generated great demand for its commercial production methods, which in turn calls for the development of technically and economically sound process technologies. This paper explores the applicability of ultrasound in the optimization of low-cost feedstock – in this case waste cooking oil – in the transesterification conversion to biodiesel. It was found that the conversion efficiency of the waste oil using ultrasound was higher than with the mechanical stirring method. The optimized variables of 6:1 methanol/oil ratio at a reaction temperature of 30 deg C and a reaction time of 30 min and 0.75% KOH (wt/wt) catalyst concentration was obtained for the transesterification of the waste oil via the use of ultrasound.

  9. Solid state frequency conversion technology for remote sensing

    International Nuclear Information System (INIS)

    Velsko, S.P.; Webb, M.S.; Cook, W.M.; Neuman, W.A.

    1994-07-01

    Long range remote sensing from airborne or other highly mobile platforms will require high average power tunable radiation from very compact and efficient laser systems. The solid state laser pumped optical parametric oscillator (OPO) has emerged as a leading candidate for such high average power, widely tunable sources. In contrast to laboratory systems, efficiency and simplicity can be the decisive issues which determine the practicality of a particular airborne remote sensing application. The recent advent of diode laser pumped solid state lasers has produced high average power OPO pump sources which are themselves both compact and efficient. However, parametric oscillator technology which can efficiently convert the average powers provided by these pump sources remains to be demonstrated. In addition to the average power requirement, many airborne long range sensing tasks will require a high degree of frequency multiplexing to disentangle data from multiple chemical species. A key advantage in system simplicity can be obtained, for example, if a single OPO can produce easily controlled multispectral output. In this paper the authors address several topics pertaining to the conversion efficiency, power handling, and multispectral capabilities of OPOs which they are currently investigating. In Section 2, single pulse conversion efficiency issues are addressed, while average power effects are treated in Section 3. Section 4 is concerned with multispectral performance of a single OPO. The last section contains a short summary and some concluding remarks

  10. Low-Cost Feedstock Conversion to Biodiesel via Ultrasound Technology

    Directory of Open Access Journals (Sweden)

    Farouk Ameer

    2010-10-01

    Full Text Available Biodiesel has attracted increasing interest and has proved to be a good substitute for fossil-based fuels due to its environmental advantages and availability from renewable resources such as refined and waste vegetable oils. Several studies have shown that biodiesel is a better fuel than the fossil-derived diesel in terms of engine performance, emissions reduction, lubricity and environmental benefits. The increasing popularity of biodiesel has generated great demand for its commercial production methods, which in turn calls for the development of technically and economically sound process technologies. This paper explores the applicability of ultrasound in the optimization of low-cost feedstock – in this case waste cooking oil – in the transesterification conversion to biodiesel. It was found that the conversion efficiency of the waste oil using ultrasound was higher than with the mechanical stirring method. The optimized variables of 6:1 methanol/oil ratio at a reaction temperature of 30 °C and a reaction time of 30 min and 0.75% KOH (wt/wt catalyst concentration was obtained for the transesterification of the waste oil via the use of ultrasound.

  11. Using information technology to support knowledge conversion processes

    Directory of Open Access Journals (Sweden)

    2001-01-01

    Full Text Available One of the main roles of Information Technology in Knowledge Management programs is to accelerate the speed of knowledge transfer and creation. The Knowledge Management tools intend to help the processes of collecting and organizing the knowledge of groups of individuals in order to make this knowledge available in a shared base. Due to the largeness of the concept of knowledge, the software market for Knowledge Management seems to be quite confusing. Technology vendors are developing different implementations of the Knowledge Management concepts in their software products. Because of the variety and quantity of Knowledge Management tools available on the market, a typology may be a valuable aid to organizations that are looking for answers to specific needs. The objective of this article is to present guidelines that help to design such a typology. Knowledge Management solutions such as intranet systems, Electronic Document Management (EDM, groupware, workflow, artificial intelligence-based systems, Business Intelligence (BI, knowledge map systems, innovation support, competitive intelligence tools and knowledge portals are discussed in terms of their potential contributions to the processes of creating, registering and sharing knowledge. A number of Knowledge Management tools (Lotus Notes, Microsoft Exchange, Business Objects, Aris Toolset, File Net, Gingo, Vigipro, Sopheon have been checked. The potential of each category of solutions to support the transfer of tacit and/or explicit knowledge and to facilitate the knowledge conversion spiral in the sense of Nonaka and Takeuchi (1995 is discussed.

  12. Needs, resources and climate change: Clean and efficient conversion technologies

    KAUST Repository

    Ghoniem, Ahmed F.

    2011-02-01

    Energy "powers" our life, and energy consumption correlates strongly with our standards of living. The developed world has become accustomed to cheap and plentiful supplies. Recently, more of the developing world populations are striving for the same, and taking steps towards securing their future energy needs. Competition over limited supplies of conventional fossil fuel resources is intensifying, and more challenging environmental problems are springing up, especially related to carbon dioxide (CO 2) emissions. There is strong evidence that atmospheric CO 2 concentration is well correlated with the average global temperature. Moreover, model predictions indicate that the century-old observed trend of rising temperatures could accelerate as carbon dioxide concentration continues to rise. Given the potential danger of such a scenario, it is suggested that steps be taken to curb energy-related CO 2 emissions through a number of technological solutions, which are to be implemented in a timely fashion. These solutions include a substantial improvement in energy conversion and utilization efficiencies, carbon capture and sequestration, and expanding the use of nuclear energy and renewable sources. Some of these technologies already exist, but are not deployed at sufficiently large scale. Others are under development, and some are at or near the conceptual state. © 2010 Elsevier Ltd. All rights reserved.

  13. Effect of Induced Pluripotent Stem Cell Technology in Blood Banking

    Science.gov (United States)

    Focosi, Daniele

    2016-01-01

    Summary Population aging has imposed cost-effective alternatives to blood donations. Artificial blood is still at the preliminary stages of development, and the need for viable cells seems unsurmountable. Because large numbers of viable cells must be promptly available for clinical use, stem cell technologies, expansion, and banking represent ideal tools to ensure a regular supply. Provided key donors can be identified, induced pluripotent stem cell (iPSC) technology could pave the way to a new era in transfusion medicine, just as it is already doing in many other fields of medicine. The present review summarizes the current state of research on iPSC technology in the field of blood banking, highlighting hurdles, and promises. Significance The aging population in Western countries is causing a progressive reduction of blood donors and a constant increase of blood recipients. Because blood is the main therapeutic option to treat acute hemorrhage, cost-effective alternatives to blood donations are being actively investigated. The enormous replication capability of induced pluripotent stem cells and their promising results in many other fields of medicine could be an apt solution to produce the large numbers of viable cells required in transfusion and usher in a new era in transfusion medicine. The present report describes the potentiality, technological hurdles, and promises of induced pluripotent stem cells to generate red blood cells by redifferentiation. PMID:26819256

  14. The use of high technology in STEM education

    Science.gov (United States)

    Lakshminarayanan, Vasudevan; McBride, Annette C.

    2015-10-01

    There has been a huge increase in the use of high technology in education. In this paper we discuss some aspects of technology that have major applications in STEM education, namely, (a) virtual reality systems, (b) personal electronic response systems aka "clickers", (c) flipped classrooms, (d) mobile learning "m-Learning", (e) massive open online courses "MOOCS", (f) internet-of-things and (g) cloud computing.

  15. Advanced technologies for decomtamination and conversion of scrap metal

    Energy Technology Data Exchange (ETDEWEB)

    Valerie MacNair; Steve Sarten; Thomas Muth; Brajendra Mishra

    1999-05-27

    The Department of Energy (DOE) faces the task of decommissioning much of the vast US weapons complex. One challenge of this effort includes the disposition of large amounts of radioactively contaminated scrap metal (RSM) including but not limited to steel, nickel, copper, and aluminum. The decontamination and recycling of RSM has become a key element in the DOE's strategy for cleanup of contaminated sites and facilities. Recycling helps to offset the cost of decommissioning and saves valuable space in the waste disposal facilities. It also reduces the amount of environmental effects associated with mining new metals. Work on this project is geared toward finding decontamination and/or recycling alternatives for the RSM contained in the decommissioned gaseous diffusion plants including approximately 40,000 tons of nickel. The nickel is contaminated with Technetium-99, and is difficult to remove using traditional decontamination technologies. The project, titled ``Advanced Technologies for Decontamination and Conversion of Scrap Metal'' was proposed as a four phase project. Phase 1 and 2 are complete and Phase 3 will complete May 31, 1999. Stainless steel made from contaminated nickel barrier was successfully produced in Phase 1. An economic evaluation was performed and a market study of potential products from the recycled metal was completed. Inducto-slag refining, after extensive testing, was eliminated as an alternative to remove technetium contamination from nickel. Phase 2 included successful lab scale and pilot scale demonstrations of electrorefining to separate technetium from nickel. This effort included a survey of available technologies to detect technetium in volumetrically contaminated metals. A new process to make sanitary drums from RSM was developed and implemented. Phase 3 included a full scale demonstration of electrorefining, an evaluation of electro-refining alternatives including direct dissolution, melting of nickel into anodes, a

  16. ECUT (Energy Conversion and Utilization Technologies) program: Biocatalysis project

    Science.gov (United States)

    Baresi, Larry

    1989-03-01

    The Annual Report presents the fiscal year (FY) 1988 research activities and accomplishments, for the Biocatalysis Project of the U.S. Department of Energy, Energy Conversion and Utilization Technologies (ECUT) Division. The ECUT Biocatalysis Project is managed by the Jet Propulsion Laboratory, California Institute of Technology. The Biocatalysis Project is a mission-oriented, applied research and exploratory development activity directed toward resolution of the major generic technical barriers that impede the development of biologically catalyzed commercial chemical production. The approach toward achieving project objectives involves an integrated participation of universities, industrial companies and government research laboratories. The Project's technical activities were organized into three work elements: (1) The Molecular Modeling and Applied Genetics work element includes research on modeling of biological systems, developing rigorous methods for the prediction of three-dimensional (tertiary) protein structure from the amino acid sequence (primary structure) for designing new biocatalysis, defining kinetic models of biocatalyst reactivity, and developing genetically engineered solutions to the generic technical barriers that preclude widespread application of biocatalysis. (2) The Bioprocess Engineering work element supports efforts in novel bioreactor concepts that are likely to lead to substantially higher levels of reactor productivity, product yields and lower separation energetics. Results of work within this work element will be used to establish the technical feasibility of critical bioprocess monitoring and control subsystems. (3) The Bioprocess Design and Assessment work element attempts to develop procedures (via user-friendly computer software) for assessing the energy-economics of biocatalyzed chemical production processes, and initiation of technology transfer for advanced bioprocesses.

  17. Advanced technologies for decontamination and conversion of scrap metal

    International Nuclear Information System (INIS)

    Valerie MacNair; Steve Sarten; Thomas Muth; Brajendra Mishra

    1999-01-01

    The Department of Energy (DOE) faces the task of decommissioning much of the vast US weapons complex. One challenge of this effort includes the disposition of large amounts of radioactively contaminated scrap metal (RSM) including but not limited to steel, nickel, copper, and aluminum. The decontamination and recycling of RSM has become a key element in the DOE's strategy for cleanup of contaminated sites and facilities. Recycling helps to offset the cost of decommissioning and saves valuable space in the waste disposal facilities. It also reduces the amount of environmental effects associated with mining new metals. Work on this project is geared toward finding decontamination and/or recycling alternatives for the RSM contained in the decommissioned gaseous diffusion plants including approximately 40,000 tons of nickel. The nickel is contaminated with Technetium-99, and is difficult to remove using traditional decontamination technologies. The project, titled ''Advanced Technologies for Decontamination and Conversion of Scrap Metal'' was proposed as a four phase project. Phase 1 and 2 are complete and Phase 3 will complete May 31, 1999. Stainless steel made from contaminated nickel barrier was successfully produced in Phase 1. An economic evaluation was performed and a market study of potential products from the recycled metal was completed. Inducto-slag refining, after extensive testing, was eliminated as an alternative to remove technetium contamination from nickel. Phase 2 included successful lab scale and pilot scale demonstrations of electrorefining to separate technetium from nickel. This effort included a survey of available technologies to detect technetium in volumetrically contaminated metals. A new process to make sanitary drums from RSM was developed and implemented. Phase 3 included a full scale demonstration of electrorefining, an evaluation of electro-refining alternatives including direct dissolution, melting of nickel into anodes, a laser cutting

  18. Chronic inflammation-elicited liver progenitor cell conversion to liver cancer stem cell with clinical significance.

    Science.gov (United States)

    Li, Xiao-Feng; Chen, Cheng; Xiang, Dai-Min; Qu, Le; Sun, Wen; Lu, Xin-Yuan; Zhou, Teng-Fei; Chen, Shu-Zhen; Ning, Bei-Fang; Cheng, Zhuo; Xia, Ming-Yang; Shen, Wei-Feng; Yang, Wen; Wen, Wen; Lee, Terence Kin Wah; Cong, Wen-Ming; Wang, Hong-Yang; Ding, Jin

    2017-12-01

    The substantial heterogeneity and hierarchical organization in liver cancer support the theory of liver cancer stem cells (LCSCs). However, the relationship between chronic hepatic inflammation and LCSC generation remains obscure. Here, we observed a close correlation between aggravated inflammation and liver progenitor cell (LPC) propagation in the cirrhotic liver of rats exposed to diethylnitrosamine. LPCs isolated from the rat cirrhotic liver initiated subcutaneous liver cancers in nonobese diabetic/severe combined immunodeficient mice, suggesting the malignant transformation of LPCs toward LCSCs. Interestingly, depletion of Kupffer cells in vivo attenuated the LCSC properties of transformed LPCs and suppressed cytokeratin 19/Oval cell 6-positive tumor occurrence. Conversely, LPCs cocultured with macrophages exhibited enhanced LCSC properties. We further demonstrated that macrophage-secreted tumor necrosis factor-α triggered chromosomal instability in LPCs through the deregulation of ubiquitin D and checkpoint kinase 2 and enhanced the self-renewal of LPCs through the tumor necrosis factor receptor 1/Src/signal transducer and activator of transcription 3 pathway, which synergistically contributed to the conversion of LPCs to LCSCs. Clinical investigation revealed that cytokeratin 19/Oval cell 6-positive liver cancer patients displayed a worse prognosis and exhibited superior response to sorafenib treatment. Our results not only clarify the cellular and molecular mechanisms underlying the inflammation-mediated LCSC generation but also provide a molecular classification for the individualized treatment of liver cancer. (Hepatology 2017;66:1934-1951). © 2017 by the American Association for the Study of Liver Diseases.

  19. Induced pluripotent stem cell technology: a decade of progress.

    Science.gov (United States)

    Shi, Yanhong; Inoue, Haruhisa; Wu, Joseph C; Yamanaka, Shinya

    2017-02-01

    Since the advent of induced pluripotent stem cell (iPSC) technology a decade ago, enormous progress has been made in stem cell biology and regenerative medicine. Human iPSCs have been widely used for disease modelling, drug discovery and cell therapy development. Novel pathological mechanisms have been elucidated, new drugs originating from iPSC screens are in the pipeline and the first clinical trial using human iPSC-derived products has been initiated. In particular, the combination of human iPSC technology with recent developments in gene editing and 3D organoids makes iPSC-based platforms even more powerful in each area of their application, including precision medicine. In this Review, we discuss the progress in applications of iPSC technology that are particularly relevant to drug discovery and regenerative medicine, and consider the remaining challenges and the emerging opportunities in the field.

  20. Pre-Service Science Teachers Views on STEM Materials and STEM Competition in Instructional Technologies and Material Development Course

    Science.gov (United States)

    Cetin, Ali; Balta, Nuri

    2017-01-01

    This qualitative study was designed to introduce STEM (Science, Technology, Engineering, Mathematics) activities to preservice science teachers and identify their views about STEM materials. In this context, a competition was organized with 42 preservice science teachers (13 male- 29 female) who took Instructional Technologies and Material…

  1. Technologies for all-optical wavelength conversion in DWDM networks

    DEFF Research Database (Denmark)

    Wolfson, David; Fjelde, Tina; Kloch, Allan

    2001-01-01

    Different techniques for all-optical wavelength conversion are reviewed and the advantages and disadvantages seen from a system perspective are highlighted. All-optical wavelength conversion will play a major role in making cost-effective network nodes in future high-speed WDM networks, where...

  2. Advanced Reactor Technology/Energy Conversion Project FY17 Accomplishments.

    Energy Technology Data Exchange (ETDEWEB)

    Rochau, Gary E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2018-02-01

    The purpose of the ART Energy Conversion (EC) Project is to provide solutions to convert the heat from an advanced reactor to useful products that support commercial application of the reactor designs.

  3. Stem Cell Technology in Cardiac Regeneration: A Pluripotent Stem Cell Promise.

    Science.gov (United States)

    Duelen, Robin; Sampaolesi, Maurilio

    2017-02-01

    Despite advances in cardiovascular biology and medical therapy, heart disorders are the leading cause of death worldwide. Cell-based regenerative therapies become a promising treatment for patients affected by heart failure, but also underline the need for reproducible results in preclinical and clinical studies for safety and efficacy. Enthusiasm has been tempered by poor engraftment, survival and differentiation of the injected adult stem cells. The crucial challenge is identification and selection of the most suitable stem cell type for cardiac regenerative medicine. Human pluripotent stem cells (PSCs) have emerged as attractive cell source to obtain cardiomyocytes (CMs), with potential applications, including drug discovery and toxicity screening, disease modelling and innovative cell therapies. Lessons from embryology offered important insights into the development of stem cell-derived CMs. However, the generation of a CM population, uniform in cardiac subtype, adult maturation and functional properties, is highly recommended. Moreover, hurdles regarding tumorigenesis, graft cell death, immune rejection and arrhythmogenesis need to be overcome in clinical practice. Here we highlight the recent progression in PSC technologies for the regeneration of injured heart. We review novel strategies that might overcome current obstacles in heart regenerative medicine, aiming at improving cell survival and functional integration after cell transplantation. Copyright © 2017. Published by Elsevier B.V.

  4. Stem Cell Technology in Cardiac Regeneration: A Pluripotent Stem Cell Promise

    Directory of Open Access Journals (Sweden)

    Robin Duelen

    2017-02-01

    Full Text Available Despite advances in cardiovascular biology and medical therapy, heart disorders are the leading cause of death worldwide. Cell-based regenerative therapies become a promising treatment for patients affected by heart failure, but also underline the need for reproducible results in preclinical and clinical studies for safety and efficacy. Enthusiasm has been tempered by poor engraftment, survival and differentiation of the injected adult stem cells. The crucial challenge is identification and selection of the most suitable stem cell type for cardiac regenerative medicine. Human pluripotent stem cells (PSCs have emerged as attractive cell source to obtain cardiomyocytes (CMs, with potential applications, including drug discovery and toxicity screening, disease modelling and innovative cell therapies. Lessons from embryology offered important insights into the development of stem cell-derived CMs. However, the generation of a CM population, uniform in cardiac subtype, adult maturation and functional properties, is highly recommended. Moreover, hurdles regarding tumorigenesis, graft cell death, immune rejection and arrhythmogenesis need to be overcome in clinical practice. Here we highlight the recent progression in PSC technologies for the regeneration of injured heart. We review novel strategies that might overcome current obstacles in heart regenerative medicine, aiming at improving cell survival and functional integration after cell transplantation.

  5. Green technology for conversion of renewable hydrocarbon based on plasma-catalytic approach

    Science.gov (United States)

    Fedirchyk, Igor; Nedybaliuk, Oleg; Chernyak, Valeriy; Demchina, Valentina

    2016-09-01

    The ability to convert renewable biomass into fuels and chemicals is one of the most important steps on our path to green technology and sustainable development. However, the complex composition of biomass poses a major problem for established conversion technologies. The high temperature of thermochemical biomass conversion often leads to the appearance of undesirable byproducts and waste. The catalytic conversion has reduced yield and feedstock range. Plasma-catalytic reforming technology opens a new path for biomass conversion by replacing feedstock-specific catalysts with free radicals generated in the plasma. We studied the plasma-catalytic conversion of several renewable hydrocarbons using the air plasma created by rotating gliding discharge. We found that plasma-catalytic hydrocarbon conversion can be conducted at significantly lower temperatures (500 K) than during the thermochemical ( 1000 K) and catalytic (800 K) conversion. By using gas chromatography, we determined conversion products and found that conversion efficiency of plasma-catalytic conversion reaches over 85%. We used obtained data to determine the energy yield of hydrogen in case of plasma-catalytic reforming of ethanol and compared it with other plasma-based hydrogen-generating systems.

  6. Conversion of Isatin to Isatate as Related to Growth Promotion in Avena Coleoptile and Pisum Stem Sections 1

    Science.gov (United States)

    Chen, H.-R.; Galston, A. W.; Milstone, L.

    1966-01-01

    Isatin, (indole 2,3-dione), which promotes elongation of Pisum stem sections at concentrations exceeding 0.1 mm, promotes elongation of Avena coleoptile sections only at higher concentrations, exceeding 1 mm. Aged isatin solutions are more active than fresh solutions, due to the slow, spontaneous conversion to isatate (o-aminophenylglyoxylate). A concentration of 0.1 mm aged isatin is as active in Avena coleoptile sections as in peas. Isatate has been independently synthesized and its auxin activity in both Avena coleoptile and Pisum stem sections confirmed. The synthetic isatate is more effective than isatin in both systems. This suggests that the auxin activity of isatin is due to its conversion to isatate. PMID:16656429

  7. Sox17-Mediated XEN Cell Conversion Identifies Dynamic Networks Controlling Cell-Fate Decisions in Embryo-Derived Stem Cells

    Directory of Open Access Journals (Sweden)

    Angela C.H. McDonald

    2014-10-01

    Full Text Available Little is known about the gene regulatory networks (GRNs distinguishing extraembryonic endoderm (ExEn stem (XEN cells from those that maintain the extensively characterized embryonic stem cell (ESC. An intriguing network candidate is Sox17, an essential transcription factor for XEN derivation and self-renewal. Here, we show that forced Sox17 expression drives ESCs toward ExEn, generating XEN cells that contribute to ExEn when placed back into early mouse embryos. Transient Sox17 expression is sufficient to drive this fate change during which time cells transit through distinct intermediate states prior to the generation of functional XEN-like cells. To orchestrate this conversion process, Sox17 acts in autoregulatory and feedforward network motifs, regulating dynamic GRNs directing cell fate. Sox17-mediated XEN conversion helps to explain the regulation of cell-fate changes and reveals GRNs regulating lineage decisions in the mouse embryo.

  8. Stem Cell Technology for (Epi)genetic Brain Disorders.

    Science.gov (United States)

    Riemens, Renzo J M; Soares, Edilene S; Esteller, Manel; Delgado-Morales, Raul

    2017-01-01

    Despite the enormous efforts of the scientific community over the years, effective therapeutics for many (epi)genetic brain disorders remain unidentified. The common and persistent failures to translate preclinical findings into clinical success are partially attributed to the limited efficiency of current disease models. Although animal and cellular models have substantially improved our knowledge of the pathological processes involved in these disorders, human brain research has generally been hampered by a lack of satisfactory humanized model systems. This, together with our incomplete knowledge of the multifactorial causes in the majority of these disorders, as well as a thorough understanding of associated (epi)genetic alterations, has been impeding progress in gaining more mechanistic insights from translational studies. Over the last years, however, stem cell technology has been offering an alternative approach to study and treat human brain disorders. Owing to this technology, we are now able to obtain a theoretically inexhaustible source of human neural cells and precursors in vitro that offer a platform for disease modeling and the establishment of therapeutic interventions. In addition to the potential to increase our general understanding of how (epi)genetic alterations contribute to the pathology of brain disorders, stem cells and derivatives allow for high-throughput drugs and toxicity testing, and provide a cell source for transplant therapies in regenerative medicine. In the current chapter, we will demonstrate the validity of human stem cell-based models and address the utility of other stem cell-based applications for several human brain disorders with multifactorial and (epi)genetic bases, including Parkinson's disease (PD), Alzheimer's disease (AD), fragile X syndrome (FXS), Angelman syndrome (AS), Prader-Willi syndrome (PWS), and Rett syndrome (RTT).

  9. Technology transfer and design conversion of a dry spent fuel storage system in Ukraine

    International Nuclear Information System (INIS)

    Peacock, R.C.; Marcelli, D.G.

    1998-01-01

    A number of unique issues surfaced in the technology transfer and design conversion of a US dry spent fuel storage technology in Ukraine. Unique challenges were encountered in the areas of nuclear design conversion, technical codes and standards, material selection and qualification, fabrication, construction and testing, quality assurance, documentation, and translation and verification processes. Technology transfer and design conversion were undertaken for both concrete and steel components for the project. The overall effort presented significant technical and cultural challenges to both the US and Ukrainian side, but technical exchange and design improvements to achieve a common goal have been reached. (author)

  10. Science, Technology, Engineering and Math (STEM) Academic Librarian Positions during 2013: What Carnegie Classifications Reveal about Desired STEM Skills

    Science.gov (United States)

    Trei, Kelli

    2015-01-01

    This study analyzes the requirements and preferences of 171 science, technology, engineering, and math (STEM) academic librarian positions in the United States as advertised in 2013. This analysis compares the STEM background experience preferences with the Carnegie rankings of the employing institution. The research examines the extent to which…

  11. Reactor technology: power conversion systems and reactor operation and maintenance

    International Nuclear Information System (INIS)

    Powell, J.R.

    1977-01-01

    The use of advanced fuels permits the use of coolants (organic, high pressure helium) that result in power conversion systems with good thermal efficiency and relatively low cost. Water coolant would significantly reduce thermal efficiency, while lithium and salt coolants, which have been proposed for DT reactors, will have comparable power conversion efficiencies, but will probably be significantly more expensive. Helium cooled blankets with direct gas turbine power conversion cycles can also be used with DT reactors, but activation problems will be more severe, and the portion of blanket power in the metallic structure will probably not be available for the direct cycle, because of temperature limitations. A very important potential advantage of advanced fuel reactors over DT fusion reactors is the possibility of easier blanket maintenance and reduced down time for replacement. If unexpected leaks occur, in most cases the leaking circuit can be shut off and a redundant cooling curcuit will take over the thermal load. With the D-He 3 reactor, it appears practical to do this while the reactor is operating, as long as the leak is small enough not to shut down the reactor. Redundancy for Cat-D reactors has not been explored in detail, but appears feasible in principle. The idea of mobile units operating in the reactor chamber for service and maintenance of radioactive elements is explored

  12. Abstracts of the international scientific-practical conference on space research, technology and conversion-II

    International Nuclear Information System (INIS)

    1997-04-01

    The International Conference on space research, technology and conversion-II was held on 16-18 April, 1997 in Tashkent, Uzbekistan. The specialists discussed various aspects of space research, technology and conversion problems. More than 60 talks were presented in the meeting on the following subjects: remote sensing and the processing of satellite information; space navigation and others, including radiation effects in silicon solar cells caused by cosmic radiation. (A.A.D.)

  13. Technology Student Characteristics: Course Taking Patterns as a Pathway to STEM Disciplines

    Science.gov (United States)

    Asunda, Paul A.; Kim, Eun Sook; Westberry, Richard

    2015-01-01

    Rising concern about America's ability to maintain its competitive position in the global economy has renewed interest in STEM education. The power and the promise of STEM education is based on the need for technological literacy. Technology education is a discipline devoted to the delivery of technological literacy for all. Nevertheless, a…

  14. Wastes to Resources: Appropriate Technologies for Sewage Treatment and Conversion.

    Science.gov (United States)

    Anderson, Stephen P.

    Appropriate technology options for sewage management systems are explained in this four-chapter report. The use of appropriate technologies is advocated for its health, environmental, and economic benefits. Chapter 1 presents background information on sewage treatment in the United States and the key issues facing municipal sewage managers.…

  15. Involvement of African-American Girls in Science, Technology, Engineering, and Mathematics (STEM) Education

    Science.gov (United States)

    Nkere, Nsidi

    2016-01-01

    A qualitative case study was conducted by examining the perceptions of fifth-grade African American girls about their experiences with science, technology, engineering and mathematics (STEM) education and potential for STEM as a future career. As the United States suffers from waning participation across all demographics in STEM and a high level…

  16. The state of the art of wind energy conversion systems and technologies: A review

    International Nuclear Information System (INIS)

    Cheng, Ming; Zhu, Ying

    2014-01-01

    Highlights: • This paper reviews the state of the art of wind energy conversion systems. • Different types of common wind energy conversion systems are classified and compared. • The four most popular MPPT control methods are reviewed and compared. • The latest development of wind energy conversion technologies is introduced. • Future trends of the wind energy conversion technologies are discussed. - Abstract: This paper gives a comprehensive review of the state of the art of wind energy conversion systems (WECS) and technologies, with an emphasis on wind power generator and control. First, different types of common WECSs are classified according to their features and drive train types. The WECSs are compared on the basis of the volume, weight, cost, efficiency, system reliability and fault ride through capability. The maximum power point tracking (MPPT) control, which aims to make the generator speed meet an optimum value to ensure the maximum energy yield, plays a key role in the variable speed WECSs. A comprehensive review and comparison of the four most popular MPPT control methods are carried out and improvements for each method are presented. Furthermore, the latest development of wind energy conversion technologies is introduced, such as the brushless doubly fed induction generator (BDFIG), the stator permanent magnet synchronous generators, the magnetic-geared generators, dual power flow WECS with the electrical variable transmission (EVT) machine, and direct grid-connected WECS. Finally, the future trends of the technologies are discussed

  17. Conversion technologies of the National Academy of Sciences of Ukraine

    International Nuclear Information System (INIS)

    Shpak, A.; Borovik, S.

    1994-01-01

    The National Academy of Sciences of Ukraine has taken active part in creating elements, technology of new kinds of military equipment and armament. There existed a successful and mutually beneficial cooperation among institutes dealing with problems of natural sciences and a number of defence enterprises. Special fundamental research undertaken made significant contribution to general development of fundamental science and technology development in industry. Therefore a number of scientific research laboratories could immediately or after certain improvements be converted from military to civil applications

  18. Assessment of photovoltaic conversion technology for electricity producing in Bulgaria

    International Nuclear Information System (INIS)

    Vitanov, P.; Tyutyundzhiev, N.; Peneva, M.; Delibasheva, M.

    1996-01-01

    Characteristics of a 36W/12V solar photovoltaic converter developed in the Bulgarian Academy of Sciences have been studied. Technical description of the module containing 4 monocrystal Si solar elements is given. Each element is with conversion efficiency more than 12% and has multilayer metallization. The power generated by the module is directly proportional to solar radiation. The electric energy generated in a sunny day is more than 240 Wh and more than 7 kWh in a spring month (April). The system can work without a battery for 8 - 18 hours. The results show that the utilization of such type of economically efficient stand-alone systems is advisable for Bulgaria. 4 figs., 3 refs

  19. Technical and economic assessment of energy conversion technologies for MSW

    Energy Technology Data Exchange (ETDEWEB)

    Livingston, W.R.

    2002-07-01

    Thermal processes for municipal solid wastes (MSW) based on pyrolysis and/or gasification that have relevance to the emerging UK market are described in this report, and the results of the technical and economical assessment of these processes are presented. The Mitsui R21 Technology, the Thermoselect Process, the Nippon Steel Waste Melting Process, the Pyropleq Process, and the Compact Power Process are selected for detailed comparison on the basis of the overall technical concept, the energy balance and the requirements for consumables, environmental performance, and the technical and commercial status of the technology. Details are also given of a comparison of the novel thermal technologies with conventional mass burn incineration for MSW.

  20. Technical and economic assessment of energy conversion technologies for MSW

    International Nuclear Information System (INIS)

    Livingston, W.R.

    2002-01-01

    Thermal processes for municipal solid wastes (MSW) based on pyrolysis and/or gasification that have relevance to the emerging UK market are described in this report, and the results of the technical and economical assessment of these processes are presented. The Mitsui R21 Technology, the Thermoselect Process, the Nippon Steel Waste Melting Process, the Pyropleq Process, and the Compact Power Process are selected for detailed comparison on the basis of the overall technical concept, the energy balance and the requirements for consumables, environmental performance, and the technical and commercial status of the technology. Details are also given of a comparison of the novel thermal technologies with conventional mass burn incineration for MSW

  1. Stem cell research as innovation: expanding the ethical and policy conversation.

    Science.gov (United States)

    Dresser, Rebecca

    2010-01-01

    Research using human embryonic stem cells raises an array of complex ethical issues, including, but by no means limited to, the moral status of developing human life. Unfortunately much of the public discussion fails to take into account this complexity. Advocacy for liberal and conservative positions on human embryonic stem cell research can be simplistic and misleading. Ethical concepts such as truth-telling, scientific integrity, and social justice should be part of the debate over federal support for human embryonic stem cell research. Moreover, the debate should be conducted in accord with principles of deliberative democracy, including respect for people holding competing views.

  2. Selection of biomass thermochemical conversion technology in the Netherlands : A best worst method approach

    NARCIS (Netherlands)

    van de Kaa, G.; Kamp, L.M.; Rezaei, J.

    2017-01-01

    This paper studies the technology battle for biomass conversion in the Netherlands. Three types of technologies are currently fighting the battle for standard dominance: combustion, pyrolysis, and gasification. Twelve relevant factors for standard dominance were found: ‘financial strength’,

  3. Myths and Motives behind STEM (Science, Technology, Engineering, and Mathematics) Education and the STEM-Worker Shortage Narrartive

    Science.gov (United States)

    Stevenson, Heidi J.

    2014-01-01

    The Business Roundtable (2013) website presents a common narrative in regard to STEM (Science, Technology, Engineering and Mathematics) education, "American students are falling behind in math and science. Fewer and fewer students are pursuing careers in science, technology, engineering and mathematics, and American students are performing at…

  4. Pluripotent Conversion of Muscle Stem Cells Without Reprogramming Factors or Small Molecules.

    Science.gov (United States)

    Bose, Bipasha; Shenoy P, Sudheer

    2016-02-01

    Muscle derived stem cells (MDSCs) are multipotent stem cells that can differentiate into several lineages including skeletal muscle precursor cells. Here, we show that MDSCs from myostatin null mice (Mstn (-/-) ) can be readily induced into pluripotent stem cells without using reprogramming factors. Microarray studies revealed a strong upregulation of markers like Leukemia Inhibitory factor (LIF) and Leukemia Inhibitory factor receptor (LIFR) in Mstn (-/-) MDSCs as compared to wild type MDSCs (WT-MDSCs). Furthermore when cultured in mouse embryonic stem cell media with LIF for 95 days, Mstn (-/-) MDSCs formed embryonic stem cell (ES) like colonies. We termed such ES like cells as the culture-induced pluripotent stem cells (CiPSC). CiPSCs from Mstn (-/-) MDSCs were phenotypically similar to ESCs, expressed high levels of Oct4, Nanog, Sox2 and SSEA-1, maintained a normal karyotype. Furthermore, CiPSCs formed embryoid bodies and teratomas when injected into immunocompromised mice. In addition, CiPSCs differentiated into somatic cells of all three lineages. We further show that culturing in ES cell media, resulted in hypermethylation and downregulation of BMP2 in Mstn(-/-) MDSCs. Western blot further confirmed a down regulation of BMP2 signaling in Mstn (-/-) MDSCs in supportive of pluripotent reprogramming. Given that down regulation of BMP2 has been shown to induce pluripotency in cells, we propose that lack of myostatin epigenetically reprograms the MDSCs to become pluripotent stem cells. Thus, here we report the successful establishment of ES-like cells from adult stem cells of the non-germline origin under culture-induced conditions without introducing reprogramming genes.

  5. Advanced technologies for decontamination and conversion of scrap metals

    International Nuclear Information System (INIS)

    Muth, T.R.; Moore, J.; Olson, D.; Mishra, B.

    1994-01-01

    Recycle of radioactive scrap metals (RSM) from decommissioning of DOE uranium enrichment and nuclear weapons manufacturing facilities is mandatory to recapture the value of these metals and avoid the high cost of disposal by burial. The scrap metals conversion project detailed below focuses on the contaminated nickel associated with the gaseous diffusion plants. Stainless steel can be produced in MSC's vacuum induction melting process (VIM) to the S30400 specification using nickel as an alloy constituent. Further the case alloy can be rolled in MSC's rolling mill to the mechanical property specification for S30400 demonstrating the capability to manufacture the contaminated nickel into valuable end products at a facility licensed to handle radioactive materials. Bulk removal of Technetium from scrap nickel is theoretically possible in a reasonable length of time with the high calcium fluoride flux, however the need for the high temperature creates a practical problem due to flux volatility. Bulk decontamination is possible and perhaps more desirable if nickel is alloyed with copper to lower the melting point of the alloy allowing the use of the high calcium fluoride flux. Slag decontamination processes have been suggested which have been proven technically viable at the Colorado School of Mines

  6. Application of radiation technology to biomass conversion processes

    International Nuclear Information System (INIS)

    Castagnet, A.C.G.

    1984-01-01

    The work carried out at the Instituto de Pesquisas Energeticas e Nucleares (IPEN) is reported for the following research projects: wood powdering of pre-irradiated chips; effect of combining electron beam processing (EBP) with other pretreatments on the saccharification of lignocellulosic materials; radiation immobilization of enzymes. The EBP of eucalyptus chips at an average dose of 1.5 x 10 5 Gy allowed a reduction of the energy required to produce a given weight of wood particles smaller than 300 μm by a factor of five. Wood powder of this particle size proved to be an excellent fuel for suspension firing system and could be used as raw material to feed continuous hydrolytic processes. Conversion efficiencies of 25.8% and 53.4%, respectively, were obtained in the production of reducing sugar by enzymatic hydrolysis of eucalyptus wood and sugarcane bagasse when materials were previously irradiated at 10 5 Gy, pulverized at 50 mesh and impregnated with 2% NaOH solution. Immobilization of cellulase by radiation induced polymerization of hydroxy-ethyl-methacrylate(HEMA) was effective when made at - 78 0 C in the presence of silica gel adsorbents or polyethylene glycol. (Author) [pt

  7. Underrepresented Entrepreneurship: A Mixed Method Study Evaluating Postsecondary Persistence Approaches for Minorities in Science Technology Engineering Math (STEM) to Graduate Studies and STEM Entrepreneurship Education

    Science.gov (United States)

    Goodwyn, Kamela Joy

    2017-01-01

    Small businesses with emphasis in science, technology, engineering and math (STEM) are catalytic in launching the United States' global presence and competitiveness into the twenty-first century through innovation and technology. The projected growth compared to non-STEM occupations, is almost twice as high for STEM occupations which further…

  8. TECHNOLOGICAL AND ENVIRONMENTAL PROBLEMS CONNECTED WITH THERMAL CONVERSION OF SEWAGE SLUDGE

    Directory of Open Access Journals (Sweden)

    Alina Żogała

    2016-02-01

    Full Text Available Overview of the most common technological and environmental problems connected with thermal conversion of sewage sludge was presented in the article. Such issues as the influence of content of moisture and mineral matter on fuel properties of sludge, problem of emission of pollutants, problem of management of solid residue, risk of corrosion, were described. Besides, consolidated characteristic of the most important methods of thermal conversion of sewage sludge, with their advantages and disadvantages, was presented in the paper.

  9. Stem cell-derived vasculature: A potent and multidimensional technology for basic research, disease modeling, and tissue engineering.

    Science.gov (United States)

    Lowenthal, Justin; Gerecht, Sharon

    2016-05-06

    Proper blood vessel networks are necessary for constructing and re-constructing tissues, promoting wound healing, and delivering metabolic necessities throughout the body. Conversely, an understanding of vascular dysfunction has provided insight into the pathogenesis and progression of diseases both common and rare. Recent advances in stem cell-based regenerative medicine - including advances in stem cell technologies and related progress in bioscaffold design and complex tissue engineering - have allowed rapid advances in the field of vascular biology, leading in turn to more advanced modeling of vascular pathophysiology and improved engineering of vascularized tissue constructs. In this review we examine recent advances in the field of stem cell-derived vasculature, providing an overview of stem cell technologies as a source for vascular cell types and then focusing on their use in three primary areas: studies of vascular development and angiogenesis, improved disease modeling, and the engineering of vascularized constructs for tissue-level modeling and cell-based therapies. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Life cycle evaluation of emerging lignocellulosic ethanol conversion technologies.

    Science.gov (United States)

    Spatari, Sabrina; Bagley, David M; MacLean, Heather L

    2010-01-01

    Lignocellulosic ethanol holds promise for addressing climate change and energy security issues associated with personal transportation through lowering the fuel mixes' carbon intensity and petroleum demand. We compare the technological features and life cycle environmental impacts of near- and mid-term ethanol bioconversion technologies in the United States. Key uncertainties in the major processes: pre-treatment, hydrolysis, and fermentation are evaluated. The potential to reduce fossil energy use and greenhouse gas (GHG) emissions varies among bioconversion processes, although all options studied are considerably more attractive than gasoline. Anticipated future performance is found to be considerably more attractive than that published in the literature as being achieved to date. Electricity co-product credits are important in characterizing the GHG impacts of different ethanol production pathways; however, in the absence of near-term liquid transportation fuel alternatives to gasoline, optimizing ethanol facilities to produce ethanol (as opposed to co-products) is important for reducing the carbon intensity of the road transportation sector and for energy security.

  11. Application of Stem Cell Technology in Dental Regenerative Medicine.

    Science.gov (United States)

    Feng, Ruoxue; Lengner, Chistopher

    2013-07-01

    In this review, we summarize the current literature regarding the isolation and characterization of dental tissue-derived stem cells and address the potential of these cell types for use in regenerative cell transplantation therapy. Looking forward, platforms for the delivery of stem cells via scaffolds and the use of growth factors and cytokines for enhancing dental stem cell self-renewal and differentiation are discussed. We aim to understand the developmental origins of dental tissues in an effort to elucidate the molecular pathways governing the genesis of somatic dental stem cells. The advantages and disadvantages of several dental stem cells are discussed, including the developmental stage and specific locations from which these cells can be purified. In particular, stem cells from human exfoliated deciduous teeth may act as a very practical and easily accessibly reservoir for autologous stem cells and hold the most value in stem cell therapy. Dental pulp stem cells and periodontal ligament stem cells should also be considered for their triple lineage differentiation ability and relative ease of isolation. Further, we address the potentials and limitations of induced pluripotent stem cells as a cell source in dental regenerative. From an economical and a practical standpoint, dental stem cell therapy would be most easily applied in the prevention of periodontal ligament detachment and bone atrophy, as well as in the regeneration of dentin-pulp complex. In contrast, cell-based tooth replacement due to decay or other oral pathology seems, at the current time, an untenable approach.

  12. The Fountain of Stem Cell-Based Youth? Online Portrayals of Anti-Aging Stem Cell Technologies.

    Science.gov (United States)

    Rachul, Christen M; Percec, Ivona; Caulfield, Timothy

    2015-08-01

    The hype surrounding stem cell science has created a market opportunity for the cosmetic industry. Cosmetic and anti-aging products and treatments that make claims regarding stem cell technology are increasingly popular, despite a lack of evidence for safety and efficacy of such products. This study explores how stem cell-based products and services are portrayed to the public through online sources, in order to gain insight into the key messages available to consumers. A content analysis of 100 web pages was conducted to examine the portrayals of stem cell-based cosmetic and anti-aging products and treatments. A qualitative discourse analysis of one web page further examined how language contributes to the portrayals of these products and treatments to public audiences. The majority of web pages portrayed stem cell-based products as ready for public use. Very few web pages substantiated claims with scientific evidence, and even fewer mentioned any risks or limitations associated with stem cell science. The discourse analysis revealed that the framing and use of metaphor obscures the certainty of the efficacy of and length of time for stem cell-based anti-aging technology to be publicly available. This study highlights the need to educate patients and the public on the current limits of stem cell applications in this context. In addition, generating scientific evidence for stem cell-based anti-aging and aesthetic applications is needed for optimizing benefits and minimizing adverse effects for the public. Having more evidence on efficacy and risks will help to protect patients who are eagerly seeking out these treatments. © 2015 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  13. The Impacts on Illegal Farmland Conversion of Adopting Remote Sensing Technology for Land Inspection in China

    Directory of Open Access Journals (Sweden)

    Taiyang Zhong

    2014-07-01

    Full Text Available While China’s central government has adopted remote sensing technology in land inspection since 2000, little empirical research has been done on its effect. This study aims to measure the effect of satellite imagery-based land inspection (SIBI on illegal farmland conversion. The data used in this study were collected for the period from 1997 to 2010 at the province-level. The econometrics approach for panel data model was used in this research. The results showed that SIBI has a deterrent effect of approximately 2.42 ha for every increase of 1% in proportion to the area of prefecture-level regions inspected in a province-level region. The results also indicate land inspections with RS (Remote Sensing technology saved approximately 11,880 ha farmland from illegal conversion during 2000–2010 with an estimated contribution of reducing illegal farmland conversion by nearly 11%. Furthermore, the governance structure change for land inspection has also contributed to deterring illegal farmland conversion. The deterrent effects due to land inspection by the Supervisor of State Land (SSL are about 7332 ha during 2008–2010 with an estimated contribution of reducing illegal farmland conversion by nearly 33%. In conclusion, although SIBI has strengthened China’s central capacity to uncover illegal farmland conversion and weakened local governments’ abilities to hide illegal farmland conversion, it has limited impact on illegal farmland conversion since it is just a technical tool. Improvements in the land inspection governance structure have also helped to deter illegal farmland conversion.

  14. From STEM to STEAM: Strategies for Enhancing Engineering & Technology Education

    Directory of Open Access Journals (Sweden)

    Andy M. Connor

    2015-05-01

    Full Text Available This paper sets out to challenge the common pedagogies found in STEM (Science, Technology, Engineering and Mathematics education with a particular focus on engineering. The dominant engineering pedagogy remains “chalk and talk”; despite research evidence that demonstrates its ineffectiveness. Such pedagogical approaches do not embrace the possibilities provided by more student-centric approaches and more active learning. The paper argues that there is a potential confusion in engineering education around the role of active learning approaches, and that the adoption of these approaches may be limited as a result of this confusion, combined with a degree of disciplinary egocentrism. The paper presents examples of design, engineering and technology projects that demonstrate the effectiveness of adopting pedagogies and delivery methods more usually attributed to the liberal arts such as studio based learning. The paper concludes with some suggestions about how best to create a fertile environment from which inquiry based learning can emerge as well as a reflection on whether the only real limitation on cultivating such approaches is the disciplinary egocentrism of traditional engineering educators.

  15. Human embryonic stem cell technologies and drug discovery.

    Science.gov (United States)

    Jensen, Janne; Hyllner, Johan; Björquist, Petter

    2009-06-01

    Development of new drugs is costly and takes huge resources into consideration. The big pharmaceutical companies are currently facing increasing developmental costs and a lower success-rate of bringing new compounds to the market. Therefore, it is now of outmost importance that the drug-hunting companies minimize late attritions due to sub-optimal pharmacokinetic properties or unexpected toxicity when entering the clinical programs. To achieve this, a strong need to test new candidate drugs in assays of high human relevance in vitro as early as possible has been identified. The traditionally used cell systems are however remarkably limited in this sense, and new improved technologies are of greatest importance. The human embryonic stem cells (hESC) is one of the most powerful cell types known. They have not only the possibility to divide indefinitely; these cells can also differentiate into all mature cell types of the human body. This makes them potentially very valuable for pharmaceutical development, spanning from use as tools in early target studies, DMPK or safety assessment, as screening models to find new chemical entities modulating adult stem cell fate, or as the direct use in cell therapies. This review illustrates the use of hESC in the drug discovery process, today, as well as in a future perspective. This will specifically be exemplified with the most important cell type for pharmaceutical development-the hepatocyte. We discuss how hESC-derived hepatocyte-like cells could improve this process, and how these cells should be cultured if optimized functionality and usefulness should be achieved. J. Cell. Physiol. 219: 513-519, 2009. (c) 2009 Wiley-Liss, Inc.

  16. Advanced technologies for decontamination and conversion of scrap metal

    International Nuclear Information System (INIS)

    MacNair, V.; Muth, T.; Shasteen, K.; Liby, A.; Hradil, G.; Mishra, B.

    1996-01-01

    In October 1993, Manufacturing Sciences Corporation was awarded DOE contract DE-AC21-93MC30170 to develop and test recycling of radioactive scrap metal (RSM) to high value and intermediate and final product forms. This work was conducted to help solve the problems associated with decontamination and reuse of the diffusion plant barrier nickel and other radioactively contaminated scrap metals present in the diffusion plants. Options available for disposition of the nickel include decontamination and subsequent release or recycled product manufacture for restricted end use. Both of these options are evaluated during the course of this research effort. work during phase I of this project successfully demonstrated the ability to make stainless steel from barrier nickel feed. This paved the way for restricted end use products made from stainless steel. Also, after repeated trials and studies, the inducto-slag nickel decontamination process was eliminated as a suitable alternative. Electro-refining appeared to be a promising technology for decontamination of the diffusion plant barrier material. Goals for phase II included conducting experiments to facilitate the development of an electro-refining process to separate technetium from nickel. In parallel with those activities, phase II efforts were to include the development of the necessary processes to make useful products from radioactive scrap metal. Nickel from the diffusion plants as well as stainless steel and carbon steel could be used as feed material for these products

  17. Conversion of Human Fibroblasts to Stably Self-Renewing Neural Stem Cells with a Single Zinc-Finger Transcription Factor

    Directory of Open Access Journals (Sweden)

    Ebrahim Shahbazi

    2016-04-01

    Full Text Available Direct conversion of somatic cells into neural stem cells (NSCs by defined factors holds great promise for mechanistic studies, drug screening, and potential cell therapies for different neurodegenerative diseases. Here, we report that a single zinc-finger transcription factor, Zfp521, is sufficient for direct conversion of human fibroblasts into long-term self-renewable and multipotent NSCs. In vitro, Zfp521-induced NSCs maintained their characteristics in the absence of exogenous factor expression and exhibited morphological, molecular, developmental, and functional properties that were similar to control NSCs. In addition, the single-seeded induced NSCs were able to form NSC colonies with efficiency comparable with control NSCs and expressed NSC markers. The converted cells were capable of surviving, migrating, and attaining neural phenotypes after transplantation into neonatal mouse and adult rat brains, without forming tumors. Moreover, the Zfp521-induced NSCs predominantly expressed rostral genes. Our results suggest a facilitated approach for establishing human NSCs through Zfp521-driven conversion of fibroblasts.

  18. Combinatorial enzyme technology: Conversion of pectin to oligo species and its effect on microbial growth

    Science.gov (United States)

    Plant cell wall polysaccharides, which consist of polymeric backbones with various types of substitution, were studied using the concept of combinatorial enzyme technology for conversion of agricultural fibers to functional products. Using citrus pectin as the starting substrate, an active oligo spe...

  19. Cogeneration Technology Alternatives Study (CTAS). Volume 3: Energy conversion system characteristics

    Science.gov (United States)

    1980-01-01

    Six current and thirty-six advanced energy conversion systems were defined and combined with appropriate balance of plant equipment. Twenty-six industrial processes were selected from among the high energy consuming industries to serve as a frame work for the study. Each conversion system was analyzed as a cogenerator with each industrial plant. Fuel consumption, costs, and environmental intrusion were evaluated and compared to corresponding traditional values. The advanced energy conversion technologies indicated reduced fuel consumption, costs, and emissions. Fuel energy savings of 10 to 25 percent were predicted compared to traditional on site furnaces and utility electricity. With the variety of industrial requirements, each advanced technology had attractive applications. Fuel cells indicated the greatest fuel energy savings and emission reductions. Gas turbines and combined cycles indicated high overall annual savings. Steam turbines and gas turbines produced high estimated returns. In some applications, diesels were most efficient. The advanced technologies used coal derived fuels, or coal with advanced fluid bed combustion or on site gasifications. Data and information for both current and advanced energy conversion technology are presented. Schematic and physical descriptions, performance data, equipment cost estimates, and predicted emissions are included. Technical developments which are needed to achieve commercialization in the 1985-2000 period are identified.

  20. Reverse engineering human neurodegenerative disease using pluripotent stem cell technology.

    Science.gov (United States)

    Liu, Ying; Deng, Wenbin

    2016-05-01

    With the technology of reprogramming somatic cells by introducing defined transcription factors that enables the generation of "induced pluripotent stem cells (iPSCs)" with pluripotency comparable to that of embryonic stem cells (ESCs), it has become possible to use this technology to produce various cells and tissues that have been difficult to obtain from living bodies. This advancement is bringing forth rapid progress in iPSC-based disease modeling, drug screening, and regenerative medicine. More and more studies have demonstrated that phenotypes of adult-onset neurodegenerative disorders could be rather faithfully recapitulated in iPSC-derived neural cell cultures. Moreover, despite the adult-onset nature of the diseases, pathogenic phenotypes and cellular abnormalities often exist in early developmental stages, providing new "windows of opportunity" for understanding mechanisms underlying neurodegenerative disorders and for discovering new medicines. The cell reprogramming technology enables a reverse engineering approach for modeling the cellular degenerative phenotypes of a wide range of human disorders. An excellent example is the study of the human neurodegenerative disease amyotrophic lateral sclerosis (ALS) using iPSCs. ALS is a progressive neurodegenerative disease characterized by the loss of upper and lower motor neurons (MNs), culminating in muscle wasting and death from respiratory failure. The iPSC approach provides innovative cell culture platforms to serve as ALS patient-derived model systems. Researchers have converted iPSCs derived from ALS patients into MNs and various types of glial cells, all of which are involved in ALS, to study the disease. The iPSC technology could be used to determine the role of specific genetic factors to track down what's wrong in the neurodegenerative disease process in the "disease-in-a-dish" model. Meanwhile, parallel experiments of targeting the same specific genes in human ESCs could also be performed to control

  1. Research and Technology Activities Supporting Closed-Brayton-Cycle Power Conversion System Development

    Science.gov (United States)

    Barrett, Michael J.

    2004-01-01

    The elements of Brayton technology development emphasize power conversion system risk mitigation. Risk mitigation is achieved by demonstrating system integration feasibility, subsystem/component life capability (particularly in the context of material creep) and overall spacecraft mass reduction. Closed-Brayton-cycle (CBC) power conversion technology is viewed as relatively mature. At the 2-kWe power level, a CBC conversion system Technology Readiness Level (TRL) of six (6) was achieved during the Solar Dynamic Ground Test Demonstration (SD-GTD) in 1998. A TRL 5 was demonstrated for 10 kWe-class CBC components during the development of the Brayton Rotating Unit (BRU) from 1968 to 1976. Components currently in terrestrial (open cycle) Brayton machines represent TRL 4 for similar uses in 100 kWe-class CBC space systems. Because of the baseline component and subsystem technology maturity, much of the Brayton technology task is focused on issues related to systems integration. A brief description of ongoing technology activities is given.

  2. Girls and STEM (Science, Technology, Engineering, and Mathematics) in Catholic Schools: A Mixed Methods Exploration of Interest, Confidence, and Perceptions of STEM

    Science.gov (United States)

    McKenna, Rachel Lynn-Pleis

    2016-01-01

    Over the past decade, there has been a considerable push in emphasizing STEM--an acronym standing for Science, Technology, Engineering, and Math--as an integral aspect of educational curriculums. Even though research suggests that females tend to outperform males in standardized testing in STEM areas, they remain underrepresented in STEM careers…

  3. Product information representation for feature conversion and implementation of group technology automated coding

    Science.gov (United States)

    Medland, A. J.; Zhu, Guowang; Gao, Jian; Sun, Jian

    1996-03-01

    Feature conversion, also called feature transformation and feature mapping, is defined as the process of converting features from one view of an object to another view of the object. In a relatively simple implementation, for each application the design features are automatically converted into features specific for that application. All modifications have to be made via the design features. This is the approach that has attracted most attention until now. In the ideal situation, however, conversions directly from application views to the design view, and to other applications views, are also possible. In this paper, some difficulties faced in feature conversion are discussed. A new representation scheme of feature-based parts models has been proposed for the purpose of one-way feature conversion. The parts models consist of five different levels of abstraction, extending from an assembly level and its attributes, single parts and their attributes, single features and their attributes, one containing the geometric reference element and finally one for detailed geometry. One implementation of feature conversion for rotational components within GT (Group Technology) has already been undertaken using an automated coding procedure operating on a design-feature database. This database has been generated by a feature-based design system, and the GT coding scheme used in this paper is a specific scheme created for a textile machine manufacturing plant. Such feature conversion techniques presented here are only in their early stages of development and further research is underway.

  4. Adaptation of the Science, Technology, Engineering, and Mathematics Career Interest Survey (STEM-CIS) into Turkish

    Science.gov (United States)

    Koyunlu Unlu, Zeynep; Dokme, Ilbilge; Unlu, Veli

    2016-01-01

    Problem Statement: Science, technology, engineering, and mathematics (STEM) education has recently become a remarkable research topic, especially in developed countries as a result of the skilled workforce required in the fields of the STEM. Considering that professional tendencies are revealed at early ages, determining students' interest in STEM…

  5. How to Recruit Women and Girls to the Science, Technology, Engineering, and Math (STEM) Classroom

    Science.gov (United States)

    Milgram, Donna

    2011-01-01

    Numbers do not exist for the percentage of girls in science, technology, engineering, and math (STEM) academies across the U.S. The most recent career and technical education statistics at the secondary level from the U.S. Department of Education are from 2005, and they show very low numbers of female students in STEM. The absence of women from…

  6. Integration of Media Design Processes in Science, Technology, Engineering, and Mathematics (STEM) Education

    Science.gov (United States)

    Karahan, Engin; Canbazoglu Bilici, Sedef; Unal, Aycin

    2015-01-01

    Problem Statement: Science, technology, engineering and mathematics (STEM) education aims at improving students' knowledge and skills in science and math, and thus their attitudes and career choices in these areas. The ultimate goal in STEM education is to create scientifically literate individuals who can survive in the global economy. The…

  7. Status of NASA's Advanced Radioisotope Power Conversion Technology Research and Development

    Science.gov (United States)

    Wong, Wayne A.; Anderson, David J.; Tuttle, Karen L.; Tew, Roy C.

    2006-01-01

    NASA s Advanced Radioisotope Power Systems (RPS) development program is funding the advancement of next generation power conversion technologies that will enable future missions that have requirements that can not be met by either the ubiquitous photovoltaic systems or by current Radioisotope Power Systems (RPS). Requirements of advanced radioisotope power systems include high efficiency and high specific power (watts/kilogram) in order to meet mission requirements with less radioisotope fuel and lower mass. Other Advanced RPS development goals include long-life, reliability, and scalability so that these systems can meet requirements for a variety of future space applications including continual operation surface missions, outer-planetary missions, and solar probe. This paper provides an update on the Radioisotope Power Conversion Technology Project which awarded ten Phase I contracts for research and development of a variety of power conversion technologies consisting of Brayton, Stirling, thermoelectrics, and thermophotovoltaics. Three of the contracts continue during the current Phase II in the areas of thermoelectric and Stirling power conversion. The accomplishments to date of the contractors, project plans, and status will be summarized.

  8. Three-dimensional neuroepithelial culture from human embryonic stem cells and its use for quantitative conversion to retinal pigment epithelium.

    Directory of Open Access Journals (Sweden)

    Yu Zhu

    Full Text Available A goal in human embryonic stem cell (hESC research is the faithful differentiation to given cell types such as neural lineages. During embryonic development, a basement membrane surrounds the neural plate that forms a tight, apico-basolaterally polarized epithelium before closing to form a neural tube with a single lumen. Here we show that the three-dimensional epithelial cyst culture of hESCs in Matrigel combined with neural induction results in a quantitative conversion into neuroepithelial cysts containing a single lumen. Cells attain a defined neuroepithelial identity by 5 days. The neuroepithelial cysts naturally generate retinal epithelium, in part due to IGF-1/insulin signaling. We demonstrate the utility of this epithelial culture approach by achieving a quantitative production of retinal pigment epithelial (RPE cells from hESCs within 30 days. Direct transplantation of this RPE into a rat model of retinal degeneration without any selection or expansion of the cells results in the formation of a donor-derived RPE monolayer that rescues photoreceptor cells. The cyst method for neuroepithelial differentiation of pluripotent stem cells is not only of importance for RPE generation but will also be relevant to the production of other neuronal cell types and for reconstituting complex patterning events from three-dimensional neuroepithelia.

  9. Science, Technology, Engineering, and Mathematics (STEM) Education Issues and Legislative Options

    National Research Council Canada - National Science Library

    Kuenzi, Jeffrey J; Matthews, Christine M; Mangan, Bonnie F

    2006-01-01

    There is growing concern that the United States is not preparing a sufficient number of students, teachers, and practitioners in the areas of science, technology, engineering, and mathematics (STEM...

  10. Higher education technological knowledge and patterns of technology adoptions in undergraduate STEM courses

    Science.gov (United States)

    Ali, Zarka Asghar

    Identifying, examining, and understanding faculty members' technological knowledge development and the process of technology adoption in higher education is a multifaceted process. Past studies have used Rogers (1995, 2003) diffusion of innovation theoretical framework to delineate the technology adoption process. These studies, however, have frequently reported the influencing factors based on the statistical analysis such as regression analysis-based approach, and have not focused on the emerging process of technology adoptions or the developing process of technological knowledge and pedagogical knowledge. A mixed method study was designed to see how faculty members acquire different technologies and develop technological knowledge that might help them adopt technologies in their classrooms and online using different pedagogies. A sample of STEM teaching faculty members with different ranks, tenure, teaching experience, and varied degree of experience in the use of educational technologies participated in the study. A survey was designed to identify internal and external factors affecting technology adoption and its effective use in different teaching activities. To elaborate survey results, the study also included class observations as well as pre- and post-observation interviews. Online classrooms used by the faculty via Blackboard learning management system, online flipped classrooms, or other websites such as Piazza were also examined for data triangulation. The findings of the study indicate that faculty members are influenced by their own professional motivations and student learning to improve their teaching methods and to enhance student interactions and learning through the use of different educational technologies. The adoption process was identified as spreading over a period of time and it looked at how faculty members' developed their technological knowledge and pedagogical knowledge. With the recognition of the social, organizational, and

  11. Examining the Quality of Technology Implementation in STEM Classrooms: Demonstration of an Evaluative Framework

    Science.gov (United States)

    Parker, Caroline E.; Stylinski, Cathlyn D.; Bonney, Christina R.; Schillaci, Rebecca; McAuliffe, Carla

    2015-01-01

    Technology applications aligned with science, technology, engineering, and math (STEM) workplace practices can engage students in real-world pursuits but also present dramatic challenges for classroom implementation. We examined the impact of teacher professional development focused on incorporating these workplace technologies in the classroom.…

  12. Applying Laser Cutting Techniques through Horology for Teaching Effective STEM in Design and Technology

    Science.gov (United States)

    Jones, Lewis C. R.; Tyrer, John R.; Zanker, Nigel P.

    2013-01-01

    This paper explores the pedagogy underpinning the use of laser manufacturing methods for the teaching of science, technology, engineering and mathematics (STEM) at key stage 3 design and technology. Clock making (horology) has been a popular project in design and technology (D&T) found in many schools, typically it focuses on aesthetical…

  13. Work Began on Contracts for Radioisotope Power Conversion Technology Research and Development

    Science.gov (United States)

    Wong, Wayne A.

    2005-01-01

    NASA has had a history of successful space flight missions that depended on radioisotope-fueled power systems. These Radioisotope Power Systems (RPSs) converted the heat generated from the decay of radioisotope material into useful electrical power. An RPS is most attractive in applications where photovoltaics are not optimal, such as deep-space applications where the solar flux is too low or extended applications on planets such as Mars where the day/night cycle, settling of dust, and life requirements limit the usefulness of photovoltaics. NASA s Radioisotope Power Conversion Technology (RPCT) Program is developing next-generation power-conversion technologies that will enable future missions that have requirements that cannot be met by the two RPS flight systems currently being developed by the Department of Energy for NASA: the Multi-Mission Radioisotope Thermoelectric Generator and the Stirling Radioisotope Generator (SRG).

  14. Research on novel coal conversion technology for energy and environment in 21st century

    Energy Technology Data Exchange (ETDEWEB)

    T. Takarada [Gunma University (Japan)

    2003-07-01

    In the 21st century, more efficient coal conversion technology will be needed. In this paper, novel gasification, pyrolysis and desulfurization processes using active catalysts are introduced. In particular, the application of ion-exchanged metals in brown coal to coal conversion technology is featured in this study. Other topics discussed include: Catalysis of mineral matter in coal; Catalytic effectiveness of Ni and K{sub 2}CO{sub 3} for various coals; Direct production of methane from steam gasification; Preparation of active catalysts from NaCl and KCl using brown coal; Gasification of high rank coal by mixing K-exchanged brown coal; Recovery of sulfur via catalytic SO{sub 2} gasification of coal char; Research on novel coal conversion technology BTX production by hydropyrolysis of coal in PPFB using catalyst; High BTU gas production by low-temperature catalytic hydropyrolysis of coal; and Ca-exchanged brown coal as SO{sub 2} and H{sub 2}S sorbents. 12 refs., 17 figs.

  15. Food waste-to-energy conversion technologies: current status and future directions.

    Science.gov (United States)

    Pham, Thi Phuong Thuy; Kaushik, Rajni; Parshetti, Ganesh K; Mahmood, Russell; Balasubramanian, Rajasekhar

    2015-04-01

    Food waste represents a significantly fraction of municipal solid waste. Proper management and recycling of huge volumes of food waste are required to reduce its environmental burdens and to minimize risks to human health. Food waste is indeed an untapped resource with great potential for energy production. Utilization of food waste for energy conversion currently represents a challenge due to various reasons. These include its inherent heterogeneously variable compositions, high moisture contents and low calorific value, which constitute an impediment for the development of robust, large scale, and efficient industrial processes. Although a considerable amount of research has been carried out on the conversion of food waste to renewable energy, there is a lack of comprehensive and systematic reviews of the published literature. The present review synthesizes the current knowledge available in the use of technologies for food-waste-to-energy conversion involving biological (e.g. anaerobic digestion and fermentation), thermal and thermochemical technologies (e.g. incineration, pyrolysis, gasification and hydrothermal oxidation). The competitive advantages of these technologies as well as the challenges associated with them are discussed. In addition, the future directions for more effective utilization of food waste for renewable energy generation are suggested from an interdisciplinary perspective. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Symposium proceedings: environmental aspects of fuel conversion technology, IV (April 1979, Hollywood, FL)

    Energy Technology Data Exchange (ETDEWEB)

    Ayer, F.A.; Jones, N.S. (comps.)

    1979-09-01

    The proceedings document presentations made at the symposium on Environmental Aspects of Fuel Conversion Technology are presented. The symposium acted as a colloquium for discussion of environmentally related information on coal gasification and liquefaction. The program included sessions on program approach, environmental assessment, and control technology development. Process developers, process users, research scientists and state and federal government officials participated in this symposium, the fourth to be conducted by IERL-RTP on the subject since 1974. Separate abstracts have been prepared of individual presentations for inclusion in the Energy Data Base.

  17. Organizational Capability Deployment Analysis for Technology Conversion into Processes, Products and Services

    Directory of Open Access Journals (Sweden)

    Tomoe Daniela Hamanaka Gusberti

    2013-12-01

    Full Text Available This article discusses Organizational Capabilities as the basic components of business models that emerged under the New Product Development Process and Technological Management. In the context of the new Technology Based Companies Development, it adopts a qualitative research in order to identify, analyze and underpin the organizational capability deployment in a process of technology conversion into product and service. The analysis was carried out considering concepts from literature review, in a technology based enterprise started by an academic spin-off company. The analysis enabled the elicitation of a Business Model and the discussion of their components, and correspondent evolution hypothesis. The paper provides an example of capability deployment accordingly the established theory illustrated by a case study. The study not just enumerate the needed partners, resources, customer channels, it enabled the description of their connection, representing the logic behind the decision made to develop the conceptual model. This detailed representation of the model allows better addressed discussions.

  18. Perspectives for induced pluripotent stem cell technology: new insights into human physiology involved in somatic mosaicism.

    Science.gov (United States)

    Nagata, Naoki; Yamanaka, Shinya

    2014-01-31

    Induced pluripotent stem cell technology makes in vitro reprogramming of somatic cells from individuals with various genetic backgrounds possible. By applying this technology, it is possible to produce pluripotent stem cells from biopsy samples of arbitrarily selected individuals with various genetic backgrounds and to subsequently maintain, expand, and stock these cells. From these induced pluripotent stem cells, target cells and tissues can be generated after certain differentiation processes. These target cells/tissues are expected to be useful in regenerative medicine, disease modeling, drug screening, toxicology testing, and proof-of-concept studies in drug development. Therefore, the number of publications concerning induced pluripotent stem cells has recently been increasing rapidly, demonstrating that this technology has begun to infiltrate many aspects of stem cell biology and medical applications. In this review, we discuss the perspectives of induced pluripotent stem cell technology for modeling human diseases. In particular, we focus on the cloning event occurring through the reprogramming process and its ability to let us analyze the development of complex disease-harboring somatic mosaicism.

  19. Stem Cell Tracking Technologies for Neurological Regenerative Medicine Purposes

    Directory of Open Access Journals (Sweden)

    Yongtao Zheng

    2017-01-01

    Full Text Available The growing field of stem cell therapy is moving toward clinical trials in a variety of applications, particularly for neurological diseases. However, this translation of cell therapies into humans has prompted a need to create innovative and breakthrough methods for stem cell tracing, to explore the migration routes and its reciprocity with microenvironment targets in the body, to monitor and track the outcome after stem cell transplantation therapy, and to track the distribution and cell viability of transplanted cells noninvasively and longitudinally. Recently, a larger number of cell tracking methods in vivo were developed and applied in animals and humans, including magnetic resonance imaging, nuclear medicine imaging, and optical imaging. This review has been intended to summarize the current use of those imaging tools in tracking stem cells, detailing their main features and drawbacks, including image resolution, tissue penetrating depth, and biosafety aspects. Finally, we address that multimodality imaging method will be a more potential tracking tool in the future clinical application.

  20. Australian Enrolment Trends in Technology and Engineering: Putting the T and E Back into School STEM

    Science.gov (United States)

    Kennedy, JohnPaul; Quinn, Frances; Lyons, Terry

    2018-01-01

    There has been much political and educational focus on Science, Technology, Engineering and Mathematics (STEM) in Australian schools in recent years and while there has been significant research examining science and mathematics enrolments in senior high school, little is known about the corresponding trends in Technologies and engineering.…

  1. Potential Impacts of Hydrokinetic and Wave Energy Conversion Technologies on Aquatic Environments

    Energy Technology Data Exchange (ETDEWEB)

    Čada, Glenn F.

    2007-04-01

    A new generation of hydropower technologies, the kinetic hydro and wave energy conversion devices, offers the possibility of generating electricity from the movements of water, without the need for dams and diversions. The Energy Policy Act of 2005 encouraged the development of these sources of renewable energy in the United States, and there is growing interest in deploying them globally. The technologies that would extract electricity from free-flowing streams, estuaries, and oceans have not been widely tested. Consequently, the U.S. Department of Energy convened a workshop to (1) identify the varieties of hydrokinetic energy and wave energy conversion devices and their stages of development, (2) identify where these technologies can best operate, (3) identify the potential environmental issues associated with these technologies and possible mitigation measures, and (4) develop a list of research needs and/or practical solutions to address unresolved environmental issues. The article reviews the results of that workshop, focusing on potential effects on freshwater, estuarine, and marine ecosystems, and we describe recent national and international developments.

  2. Overview of micro- and nano-technology tools for stem cell applications: micropatterned and microelectronic devices.

    Science.gov (United States)

    Cagnin, Stefano; Cimetta, Elisa; Guiducci, Carlotta; Martini, Paolo; Lanfranchi, Gerolamo

    2012-11-19

    In the past few decades the scientific community has been recognizing the paramount role of the cell microenvironment in determining cell behavior. In parallel, the study of human stem cells for their potential therapeutic applications has been progressing constantly. The use of advanced technologies, enabling one to mimic the in vivo stem cell microenviroment and to study stem cell physiology and physio-pathology, in settings that better predict human cell biology, is becoming the object of much research effort. In this review we will detail the most relevant and recent advances in the field of biosensors and micro- and nano-technologies in general, highlighting advantages and disadvantages. Particular attention will be devoted to those applications employing stem cells as a sensing element.

  3. Science, technology, engineering, mathematics (STEM) as mathematics learning approach in 21st century

    Science.gov (United States)

    Milaturrahmah, Naila; Mardiyana, Pramudya, Ikrar

    2017-08-01

    This 21st century demands competent human resources in science, technology, engineering design and mathematics so that education is expected to integrate the four disciplines. This paper aims to describe the importance of STEM as mathematics learning approach in Indonesia in the 21st century. This paper uses a descriptive analysis research method, and the method reveals that STEM education growing in developed countries today can be a framework for innovation mathematics in Indonesia in the 21st century. STEM education integrate understanding of science, math skills, and the available technology with the ability to perform engineering design process. Implementation of mathematics learning with STEM approach makes graduates trained in using of mathematics knowledge that they have to create innovative products that are able to solve the problems that exist in society.

  4. A feasibility study of conceptual design for international clean energy network using hydrogen conversion technology

    International Nuclear Information System (INIS)

    Sato, Takashi; Hamada, Akiyoshi; Kitamura, Kazuhiro

    1998-01-01

    Clean energy is more and more required worldwide in proportion to actualization of global environmental issues including global warming. Therefore, it is an urgent task to realize promotion of worldwide introduction of clean energy which exists abundantly and is widely distributed in the world, such as hydropower and solar energy, while reducing the dependence on fossil fuel. However, since the renewable energy, differing from so called fossil fuel, is impossible to transport for long distance and store as it is, its utilization is subject to be limited. As one possible resolution of this kind of issues, 'International clean energy network using hydrogen conversion technology' which enables conversion of renewable energy from low cost hydropower into hydrogen energy and also into the transportable and storable form, is a meaningful concept. This system technology enables dealing of this hydrogen energy in international market as in the same manner as fossil fuel. It is considered to enable promotion of international and large scale introduction of such clean energy, along with the contribution to diversified and stabilized international energy supply. In this study, based upon the above-mentioned point of view and assumption of two sites, one on supply side and another on demand side of hydrogen energy, three systems are presumed. One of the systems consists of liquid hydrogen as transportation and storage medium of hydrogen, and the others intermediately convert hydrogen into methanol or ammonia as an energy carrier. A overall conceptual design of each system spanning from hydrogen production to its utilization, is conducted in practical way in order to review the general technical aspects and economical aspects through cost analysis. This study is administrated through the New Energy and Industrial Technology Development Organization (NEDO) as a part of the International Clean Energy Network Using Hydrogen Conversion (so-called WE-NET) Program with funding from

  5. Current Technologies Based on the Knowledge of the Stem Cells Microenvironments.

    Science.gov (United States)

    Mawad, Damia; Figtree, Gemma; Gentile, Carmine

    2017-01-01

    The stem cell microenvironment or niche plays a critical role in the regulation of survival, differentiation and behavior of stem cells and their progenies. Recapitulating each aspect of the stem cell niche is therefore essential for their optimal use in in vitro studies and in vivo as future therapeutics in humans. Engineering of optimal conditions for three-dimensional stem cell culture includes multiple transient and dynamic physiological stimuli, such as blood flow and tissue stiffness. Bioprinting and microfluidics technologies, including organs-on-a-chip, are among the most recent approaches utilized to replicate the three-dimensional stem cell niche for human tissue fabrication that allow the integration of multiple levels of tissue complexity, including blood flow. This chapter focuses on the physico-chemical and genetic cues utilized to engineer the stem cell niche and provides an overview on how both bioprinting and microfluidics technologies are improving our knowledge in this field for both disease modeling and tissue regeneration, including drug discovery and toxicity high-throughput assays and stem cell-based therapies in humans.

  6. Direct Conversion of Equine Adipose-Derived Stem Cells into Induced Neuronal Cells Is Enhanced in Three-Dimensional Culture.

    Science.gov (United States)

    Petersen, Gayle F; Hilbert, Bryan J; Trope, Gareth D; Kalle, Wouter H J; Strappe, Padraig M

    2015-12-01

    The ability to culture neurons from horses may allow further investigation into equine neurological disorders. In this study, we demonstrate the generation of induced neuronal cells from equine adipose-derived stem cells (EADSCs) using a combination of lentiviral vector expression of the neuronal transcription factors Brn2, Ascl1, Myt1l (BAM) and NeuroD1 and a defined chemical induction medium, with βIII-tubulin-positive induced neuronal cells displaying a distinct neuronal morphology of rounded and compact cell bodies, extensive neurite outgrowth, and branching of processes. Furthermore, we investigated the effects of dimensionality on neuronal transdifferentiation, comparing conventional two-dimensional (2D) monolayer culture against three-dimensional (3D) culture on a porous polystyrene scaffold. Neuronal transdifferentiation was enhanced in 3D culture, with evenly distributed cells located on the surface and throughout the scaffold. Transdifferentiation efficiency was increased in 3D culture, with an increase in mean percent conversion of more than 100% compared to 2D culture. Additionally, induced neuronal cells were shown to transit through a Nestin-positive precursor state, with MAP2 and Synapsin 2 expression significantly increased in 3D culture. These findings will help to increase our understanding of equine neuropathogenesis, with prospective roles in disease modeling, drug screening, and cellular replacement for treatment of equine neurological disorders.

  7. Science, Technology, Engineering, and Mathematics (STEM) Education Reform to Enhance Security of the Global Cyberspace

    Science.gov (United States)

    2014-05-01

    towards cloud computing technologies and capabilities demand needs for developing new tools that work in ensemble to handle security challenges. A...programs with the schools and/or hire from their pool of students. Therefore, no real STEM standards exist at the tertiary and beyond levels of education ...successful in cyber operations and network security related jobs much early on into the new STEM education model pipeline. Subjects such as computer

  8. Comparative efficiency of technologies for conversion and transportation of energy resources of Russia's eastern regions to NEA countries

    Science.gov (United States)

    Kler, Aleksandr; Tyurina, Elina; Mednikov, Aleksandr

    2018-01-01

    The paper presents perspective technologies for combined conversion of fossil fuels into synthetic liquid fuels and electricity. The comparative efficiency of various process flows of conversion and transportation of energy resources of Russia's east that are aimed at supplying electricity to remote consumers is presented. These also include process flows based on production of synthetic liquid fuel.

  9. Stem Cell Technology in Cardiac Regeneration: A Pluripotent Stem Cell Promise

    OpenAIRE

    Robin Duelen; Maurilio Sampaolesi

    2017-01-01

    Despite advances in cardiovascular biology and medical therapy, heart disorders are the leading cause of death worldwide. Cell-based regenerative therapies become a promising treatment for patients affected by heart failure, but also underline the need for reproducible results in preclinical and clinical studies for safety and efficacy. Enthusiasm has been tempered by poor engraftment, survival and differentiation of the injected adult stem cells. The crucial challenge is identification and s...

  10. Using Food Science Demonstrations to Engage Students of All Ages in Science, Technology, Engineering, and Mathematics (STEM)

    Science.gov (United States)

    Schmidt, Shelly J.; Bohn, Dawn M.; Rasmussen, Aaron J.; Sutherland, Elizabeth A.

    2012-01-01

    The overarching goal of the Science, Technology, Engineering, and Mathematics (STEM) Education Initiative is to foster effective STEM teaching and learning throughout the educational system at the local, state, and national levels, thereby producing science literate citizens and a capable STEM workforce. To contribute to achieving this goal, we…

  11. National STEM School Education Strategy: A Comprehensive Plan for Science, Technology, Engineering and Mathematics Education in Australia

    Science.gov (United States)

    Education Council, 2015

    2015-01-01

    There are many factors that affect student engagement in science, technology, engineering and mathematics (STEM). Underlying this are the views of the broader community--and parents in particular--about the relevance of STEM, and the approach to the teaching and learning of STEM from the early years and continuing throughout schooling. Connected…

  12. Possible improvements of efficiency by the use of new coal conversion technologies

    International Nuclear Information System (INIS)

    Krieb, K.H.

    1976-01-01

    Following a comparison of the efficiencies of conventional steam power processes, the gas fuel cell and the combined gas steam turbine processes are introduced as new coal utilization technologies. Coal conversion processes which can be coupled to combined gas-steam turbine processes such as the fluidized-bed firing, the solid bed gasification, the dust part-gasification and the fluidized-bed gasification are more closely mentioned and their coupling efficiencies discussed. The decoupling of third energy, such as low-temperature heat, high-temperature heat and chemical energy are briefly dealt with as third possibility for the improvement of the efficiency. (GG/LH) [de

  13. Development and validation of science, technology, engineering and mathematics (STEM) based instructional material

    Science.gov (United States)

    Gustiani, Ineu; Widodo, Ari; Suwarma, Irma Rahma

    2017-05-01

    This study is intended to examine the development and validation of simple machines instructional material that developed based on Science, Technology, Engineering and Mathematics (STEM) framework that provides guidance to help students learn and practice for real life and enable individuals to use knowledge and skills they need to be an informed citizen. Sample of this study consist of one class of 8th grader at a junior secondary school in Bandung, Indonesia. To measure student learning, a pre-test and post-test were given before and after implementation of the STEM based instructional material. In addition, a questionnaire of readability was given to examine the clarity and difficulty level of each page of instructional material. A questionnaire of students' response towards instructional material given to students and teachers at the end of instructional material reading session to measure layout aspects, content aspects and utility aspects of instructional material for being used in the junior secondary school classroom setting. The results show that readability aspect and students' response towards STEM based instructional material of STEM based instructional material is categorized as very high. Pretest and posttest responses revealed that students retained significant amounts information upon completion of the STEM instructional material. Student overall learning gain is 0.67 which is categorized as moderate. In summary, STEM based instructional material that was developed is valid enough to be used as educational materials necessary for conducting effective STEM education.

  14. The Status of Thermophotovoltaic Energy Conversion Technology at Lockheed Martin Corporation

    Energy Technology Data Exchange (ETDEWEB)

    EJ Brown; PF Baldasaro; SR Burger; LR Danielson; DM DePoy; JM Dolatowski; PM Fourspring; GJ Nichols; WF Topper; TD Rahmlow

    2004-07-29

    In a thermophotovoltaic (TPV) energy conversion system, a heated surface radiates in the mid-infrared range onto photocells which are sensitive at these energies. Part of the absorbed energy is converted into electric output. Conversion efficiency is maximized by reducing the absorption of non-convertible energy with some form of spectral control. In a TPV system, many technology options exist. Our development efforts have concentrated on flat-plate geometries with greybody radiators, front surface tandem filters and a multi-chip module (MCM) approach that allows selective fabrication processes to match cell performance. Recently, we discontinued development of GaInAsSb quaternary cell semiconductor material in favor of ternary GaInAs material. In our last publication (Ref. 1), the authors reported conversion efficiencies of about 20% (radiator 950 C, cells 22 C) for small modules (1-4 cm{sup 2}) tested in a prototypic cavity test environment. Recently, we have achieved measured conversion efficiencies of about 12.5% in larger ({approx}100 cm{sup 2}) test arrays. The efficiency reduction in the larger arrays was probably due to quality and variation of the cells as well as non-uniform illumination from the hot radiator to the cold plate. Modules in these tests used GaInAsSb cells with 0.52 eV bandgap and front surface filters for spectral control. This paper provides details of the individual system components and the rationale for our technical decisions. It also describes the measurement techniques used to record these efficiencies.

  15. Development of nuclear technologies and conversion of nuclear weapon testing system infrastructure in Kazakhstan

    International Nuclear Information System (INIS)

    Cherepnin, Yu.; Takibaev, Zh.

    2000-01-01

    The article gives a brief description of the work done by the National Nuclear Center of the Republic of Kazakhstan in development of nuclear technology and conversion of nuclear weapon testing infrastructure in Kazakhstan. Content and trends of works are as follows: 1. Peaceful use of all physical facilities, created earlier for nuclear tests in Kazakhstan; 2. Development of methods and technologies for safe nuclear reactors use; 3. Examination of different materials in field of great neutron flow for thermonuclear reactor's first wall development; 4. Liquidation of all wells, which were formed in the results of underground nuclear explosions in Degelen mountain massif of former Semipalatinsk test site; 5. Study of consequences of nuclear tests in West Kazakhstan (territory of Azgir test site and Karachaganak oil field); 6. Study of radiological situation on the Semipalatinsk test site and surrounding territories; 7. Search of ways for high-level radioactive wastes disposal; 8. Construction of safe nuclear power plants in Kazakhstan

  16. Zero Waste and Conversion Efficiencies of Various Technologies for Disposal of Municipal Solid Waste

    Institute of Scientific and Technical Information of China (English)

    Zhang Wenyang

    2005-01-01

    Zero waste is a philosophy and a design principle of dealing with our waste stream for the 21st century. After reviewing the available information, the goal of zero waste from landfill is considered to be unachievable by using known and proven methods and approaches. The comparison of various technologies shows that the conversion efficiencies depend upon the type of system chosen for processing residual waste, and the best overall diversion rate of waste management system that can be achieved is about 71%. The maximum achievable overall diversion rate can be increased to approximate 92% if current environmental regulations to permit the routine use of the bottom ash or char for advanced thermal technologies.

  17. Prospects of power conversion technology of direct-cycle helium gas turbine for MHTGR

    International Nuclear Information System (INIS)

    Li Yong; Zhang Zuoyi

    1999-01-01

    The modular high temperature gas cooled reactor (MHTGR) is a modern passively safe reactor. The reactor and helium gas turbine may be combined for high efficiency's power conversion, because MHTGR has high outlet temperature up to 950 degree C. Two different schemes are planed separately by USA and South Africa. the helium gas turbine methodologies adopted by them are mainly based on the developed heavy duty industrial and aviation gas turbine technology. The author introduces the differences of two technologies and some design issues in the design and manufacture. Moreover, the author conclude that directly coupling a closed Brayton cycle gas turbine concept to the passively safe MHTGR is the developing direction of MHTGR due to its efficiency which is much higher than that of using steam turbine

  18. Proton conducting polymeric materials for hydrogen based electrochemical energy conversion technologies

    DEFF Research Database (Denmark)

    Aili, David

    on the development and characterization of polymer based proton conducting membranes for operation at temperatures above 100 °C. The most frequently recurring experimental methods and techniques are described in Chapter 2. For PEM steam and liquid water electrolysis at temperatures up to 130 °C (Chapter 3 and 4...... and water electrolyzers. This thesis gives an overview of the principles and the current state-of-the-art technology of the hydrogen based electrochemical energy conversion technologies, with special emphasis on the PEM based water electrolyzers and fuel cells (Chapter 1). The fundamental thermodynamics...... of the recast Nafion® membranes at elevated temperature could be slightly improved by annealing the membrane in order to increase its degree of crystallinity. Short side chain (SSC) PFSA membranes such as Aquivion™ (Solvey Solexis), on the other hand, are generally characterized by a considerably higher degree...

  19. The Problem about Technology in STEM Education: Some Findings from Action Research on the Professional Development & Integrated STEM Lessons in Informal Fields

    Directory of Open Access Journals (Sweden)

    Tomoki Saito

    2015-04-01

    Full Text Available Since 2013, the authors’ Japanese team in the Department of Science Education at Shizuoka University has held trials of STEM Education in informal fields as participatory action research (e.g., Science museum in Shizuoka, Lifelong Learning Center in Fujieda City, and STEM Summer camp for the preparation for implementing STEM education in public schools and for proposing science education reform in a Japanese context. Problems in preparing STEM lessons include numerous new instructional materials and programs and emerging specialized schools. In addition, while most of these initiatives address one or more of the STEM subjects separately, there are increasing calls for emphasizing connections between and among the subjects (Honey, Pearson and Schweingruber, 2014. Unfamiliar problems for Japanese teachers are, What is Engineering? What is Design? and How can they be implemented in lessons? While gathering STEM learning materials to implement in their STEM Summer Camp, the authors noticed a pattern with which to develop a STEM lesson and developed a template “T-SM-E” in reference to prior STEM studies. After the STEM Summer Camp, the authors introduced the model in the pre-service teacher preparation program. As a result, the authors received suggestions about how teachers can develop integrated STEM lessons, how undergraduate (UG teachers can implement it in their lessons, and how teachers can assess student learning in their STEM lessons. From standard based student assessments and reflections written by the UG teachers, the authors found that it was difficult for the UG teachers to include technology in their lessons, and their assessment also indicated that the students did not show performance proficiency in technology. The authors discuss this existing problem in the Japanese education system.

  20. Development of high level radwaste treatment and conversion technology. Transmutation technology development

    Energy Technology Data Exchange (ETDEWEB)

    Park, Won Suk; Song, T Y; Kim, Y H

    2001-03-01

    The final disposition of spent fuel has been, and continues to be, an important issue of nuclear industry. The conceptual design for the accelerator driven transmutation system HYPER is scheduled to be completed by the year of 2006. As the first step for the conceptual design, a study to determine 1. sub-critical core characteristics, 2. fuel concept, 3. coolant system concept, 4. spallation target concept for the HYPER was performed from 1997 to 2000. Most of concept studies were done on the literature basis. The major objectives of the study is to give a guid-line for the second stage research which will be performed during 2001-2003. In addition, the technologies related with TRU-Zr fuel and Pb-Bi coolant can be utilized for the future nuclear reactor development such as generation 4.

  1. Development of high level radwaste treatment and conversion technology. Transmutation technology development

    International Nuclear Information System (INIS)

    Park, Won Suk; Song, T. Y.; Kim, Y. H.

    2001-03-01

    The final disposition of spent fuel has been, and continues to be, an important issue of nuclear industry. The conceptual design for the accelerator driven transmutation system HYPER is scheduled to be completed by the year of 2006. As the first step for the conceptual design, a study to determine 1. sub-critical core characteristics, 2. fuel concept, 3. coolant system concept, 4. spallation target concept for the HYPER was performed from 1997 to 2000. Most of concept studies were done on the literature basis. The major objectives of the study is to give a guid-line for the second stage research which will be performed during 2001-2003. In addition, the technologies related with TRU-Zr fuel and Pb-Bi coolant can be utilized for the future nuclear reactor development such as generation 4

  2. Mobile STEMship Discovery Center: K-12 Aerospace-Based Science, Technology, Engineering, and Mathematics (STEM) Mobile Teaching Vehicle

    Science.gov (United States)

    2015-08-03

    AND SUBTITLE Mobile STEMship Discovery Center: K-12 Aerospace-Based Science, Technology, Engineering, and Mathematics (STEM) Mobile Teaching Vehicle...Center program to be able to expose Science Technology, Engineering and Mathematics (STEM) space-inspired science centers for DC Metro beltway schools

  3. Career Advancement Outcomes in Academic Science, Technology, Engineering and Mathematics (STEM): Gender, Mentoring Resources, and Homophily

    Science.gov (United States)

    Lee, Sang Eun

    2017-01-01

    This dissertation examines gender differences in career advancement outcomes among academic science, technology, engineering and mathematics (STEM) scientists. In particular, this research examines effects of gender, PhD advisors and postdoctoral supervisors mentoring resources and gender homophily in the mentoring dyads on the career advancement…

  4. STEM the Tide: Reforming Science, Technology, Engineering, and Math Education in America

    Science.gov (United States)

    Drew, David E.

    2011-01-01

    One study after another shows American students ranking behind their international counterparts in the STEM fields--science, technology, engineering, and math. Business people such as Bill Gates warn that this alarming situation puts the United States at a serious disadvantage in the high-tech global marketplace of the twenty-first century, and…

  5. Standards for Technological Literacy and STEM Education Delivery through Career and Technical Education Programs

    Science.gov (United States)

    Asunda, Paul A.

    2012-01-01

    At a minimum, employers rely on career and technical education (CTE) and workforce training systems to supply workers able to perform in their jobs. In CTE classes that seek to integrate science, technology, engineering, and mathematics (STEM) concepts, it falls to the instructors to design and sequence the learning experiences that will promote…

  6. A tangible serious game approach to science, technology, engineering, and mathematics (STEM) education

    NARCIS (Netherlands)

    Berta, R.; Bellotti, F.; van der Spek, E.D.; Winkler, T.; Nakatsu, R.; Rauterberg, M.; Ciancarini, P.

    2015-01-01

    The chapter’s idea stems from the observation that technology is difficult to learn in an abstract way (books, lectures, etc.) and practical activities are needed not only to apply concepts but also to help learning itself. This is particularly challenging in a younger age where this concern is

  7. Early embryonic development, assisted reproductive technologies, and pluripotent stem cell biology in domestic mammals

    DEFF Research Database (Denmark)

    Hall, Vanessa Jane; Hinrichs, K.; Lazzari, G.

    2013-01-01

    production and health in animal husbandry. More recently, biomedical applications of these technologies, in particular, SCNT and stem cell culture, have been pursued in domestic mammals in order to create models for human disease and therapy. The following review focuses on presenting important aspects...

  8. Air Force-Wide Needs for Science, Technology, Engineering, and Mathematics (STEM) Academic Degrees

    Science.gov (United States)

    2014-01-01

    anthropology (0190), mathematical statistics (1529), general math (AFIT faculty only), metallurgy (1321), and actuarial science (1510). 97 Tier II. Few...linking or frEE DownloAD At www.rand.org C O R P O R A T I O N Research Report Air Force–Wide Needs for Science , Technology, Engineering, and...00-00-2014 4. TITLE AND SUBTITLE Air Force-Wide Needs for Science , Technology, Engineering, and Mathematics (STEM) Academic Degrees 5a. CONTRACT

  9. Stem cell technology using bioceramics: hard tissue regeneration towards clinical application

    Directory of Open Access Journals (Sweden)

    Hiroe Ohnishi, Yasuaki Oda and Hajime Ohgushi

    2010-01-01

    Full Text Available Mesenchymal stem cells (MSCs are adult stem cells which show differentiation capabilities toward various cell lineages. We have already used MSCs for treatments of osteoarthritis, bone necrosis and bone tumor. For this purpose, culture expanded MSCs were combined with various ceramics and then implanted. Because of rejection response to allogeneic MSC implantation, we have utilized patients' own MSCs for the treatment. Bone marrow is a good cell source of MSCs, although the MSCs also exist in adipose tissue. When comparing osteogenic differentiation of these MSCs, bone marrow MSCs show more extensive bone forming capability than adipose MSCs. Thus, the bone marrow MSCs are useful for bone tissue regeneration. However, the MSCs show limited proliferation and differentiation capabilities that hindered clinical applications in some cases. Recent advances reveal that transduction of plural transcription factors into human adult cells results in generation of new type of stem cells called induced pluripotent stem cells (iPS cells. A drawback of the iPS cells for clinical applications is tumor formation after their in vivo implantation; therefore it is difficult to use iPS cells for the treatment. To circumvent the problem, we transduced a single factor of either SOX2 or NANOG into the MSCs and found high proliferation as well as osteogenic differentiation capabilities of the MSCs. The stem cells could be combined with bioceramics for clinical applications. Here, we summarize our recent technologies using adult stem cells in viewpoints of bone tissue regeneration.

  10. TOPICAL REVIEW: Stem cell technology using bioceramics: hard tissue regeneration towards clinical application

    Science.gov (United States)

    Ohnishi, Hiroe; Oda, Yasuaki; Ohgushi, Hajime

    2010-02-01

    Mesenchymal stem cells (MSCs) are adult stem cells which show differentiation capabilities toward various cell lineages. We have already used MSCs for treatments of osteoarthritis, bone necrosis and bone tumor. For this purpose, culture expanded MSCs were combined with various ceramics and then implanted. Because of rejection response to allogeneic MSC implantation, we have utilized patients' own MSCs for the treatment. Bone marrow is a good cell source of MSCs, although the MSCs also exist in adipose tissue. When comparing osteogenic differentiation of these MSCs, bone marrow MSCs show more extensive bone forming capability than adipose MSCs. Thus, the bone marrow MSCs are useful for bone tissue regeneration. However, the MSCs show limited proliferation and differentiation capabilities that hindered clinical applications in some cases. Recent advances reveal that transduction of plural transcription factors into human adult cells results in generation of new type of stem cells called induced pluripotent stem cells (iPS cells). A drawback of the iPS cells for clinical applications is tumor formation after their in vivo implantation; therefore it is difficult to use iPS cells for the treatment. To circumvent the problem, we transduced a single factor of either SOX2 or NANOG into the MSCs and found high proliferation as well as osteogenic differentiation capabilities of the MSCs. The stem cells could be combined with bioceramics for clinical applications. Here, we summarize our recent technologies using adult stem cells in viewpoints of bone tissue regeneration.

  11. The new technologies and infrastructure conversion of nuclear testing in Kazakhstan

    International Nuclear Information System (INIS)

    Kadyrzhanov, K.K.

    1999-01-01

    It is known, that in August, 1991, in accordance with Decree by the Kazakhstan President, the Semipalatinsk test site (STS) was shut down, and practical works on its conversion were initiated. In 1991 the decision on creation of the Kazakhstan National Nuclear Center (KNNC) on a base of the test site scientific and industrial enterprises and Inst. of Nuclear Physics was taken. In 1993 within frame KNNC three new institutes (Inst. of Atomic Energy, Inst. of Geophysical Research, Inst. of Radiation Safety and Ecology) were created. Owing to this, at the condition of USSR disintegration and liquidation of military division in test site territory, high-qualified personnel was saved, the facilities that represent nuclear danger were left under operation and surveillance, and the full-scale program of STS conversion was developed and put into life. At present guidelines for the major research activities at KNNC on conversion program are as follows: liquidation of consequences of nuclear tests; liquidation of technological structure used before for preparation and implementation of nuclear weapons tests; creation of technology, equipment and locations for receipt and storage of radioactive wastes; working out the concept of nuclear power development in Kazakhstan; investigation of the behaviour of melted reactor core in view of potential heavy accidents at nuclear power plants; development of technique and means for detection of nuclear test in the world, continuous control for nuclear explosions; experimental works on investigation of behaviour of the materials-candidates for role of constructional materials for the thermonuclear reactor ITER; creation of high-technology industries. These and other activities undertaken in this respect allow to attract considerable foreign investments, to create in Kurchatov city hundreds of additional working places.The Government support rendered to KNNC in future will allow to expand substantially this area of activities as well as to

  12. Identification of risks stemming from new communication technologies

    DEFF Research Database (Denmark)

    Lessis, Vasileios; Taylor, J.R.; Kozin, Igor

    Advanced distributed communication technologies play an important role today in the control and maintenance of safety -critical systems. However, the excessively optimistic reliance on the new technology without ecognizing the threats against its successful functioning, being able to maintain...... proved to be effective tools in developing more reliable and robust systems. As technology is developing fast though, a new need for an effective hazard identification methodology has emerged. To enhance the predictive performance of hazard identification in advanced distributed communication systems, we...... have envisioned and currently developing a multilevel-multidimensional HAZOP methodology. The methodology introduces a new creative thinking stimulation model to substitute the conventional guideword-based approaches that is based on a multiple level and dimension exploration of the system under...

  13. The conversion of military science and technology: Former Soviet Union case

    International Nuclear Information System (INIS)

    Martellini, M.

    1998-01-01

    The end of the Cold War which has brought deep changes in the very concept of defence, requires fundamental changes in the defence strategies of all nations, the new international situation is encouraging the conversion of the military sector for the benefit of the civilian economy. This process involves many companies that have previously worked mostly or exclusively on the basis of military orders. In particular, from the nuclear non-proliferation point of view and environmental safety standpoint, some urgent problems arise: civilian management of military nuclear technologies, management and storage of weapon-grade materials, namely plutonium and highly enriched uranium from dismantled nuclear warheads, cleaning and reusing large areas which have been taken up for the production of weapon-grade plutonium and uranium enrichment (in Soviet Union so called 'atomic sites'), retraining scientific personnel and engineers in the nuclear military industry

  14. Surface reflectance and conversion efficiency dependence of technologies for mitigating global warming

    Energy Technology Data Exchange (ETDEWEB)

    Edmonds, Ian [Solartran Pty Ltd., 12 Lentara St, Kenmore, Brisbane 4069 (Australia); Smith, Geoff [Physics and Advanced Materials, University of Technology, Sydney, PO Box 123, Broadway, New South Wales 2007 (Australia)

    2011-05-15

    A means of assessing the relative impact of different renewable energy technologies on global warming has been developed. All power plants emit thermal energy to the atmosphere. Fossil fuel power plants also emit CO{sub 2} which accumulates in the atmosphere and provides an indirect increase in global warming via the greenhouse effect. A fossil fuel power plant may operate for some time before the global warming due to its CO{sub 2} emission exceeds the warming due to its direct heat emission. When a renewable energy power plant is deployed instead of a fossil fuel power plant there may be a significant time delay before the direct global warming effect is less than the combined direct and indirect global warming effect from an equivalent output coal fired plant - the ''business as usual'' case. Simple expressions are derived to calculate global temperature change as a function of ground reflectance and conversion efficiency for various types of fossil fuelled and renewable energy power plants. These expressions are used to assess the global warming mitigation potential of some proposed Australian renewable energy projects. The application of the expressions is extended to evaluate the deployment in Australia of current and new geo-engineering and carbon sequestration solutions to mitigate global warming. Principal findings are that warming mitigation depends strongly on the solar to electric conversion efficiency of renewable technologies, geo-engineering projects may offer more economic mitigation than renewable energy projects and the mitigation potential of reforestation projects depends strongly on the location of the projects. (author)

  15. Recent technological updates and clinical applications of induced pluripotent stem cells.

    Science.gov (United States)

    Diecke, Sebastian; Jung, Seung Min; Lee, Jaecheol; Ju, Ji Hyeon

    2014-09-01

    Induced pluripotent stem cells (iPSCs) were first described in 2006 and have since emerged as a promising cell source for clinical applications. The rapid progression in iPSC technology is still ongoing and directed toward increasing the efficacy of iPSC production and reducing the immunogenic and tumorigenic potential of these cells. Enormous efforts have been made to apply iPSC-based technology in the clinic, for drug screening approaches and cell replacement therapy. Moreover, disease modeling using patient-specific iPSCs continues to expand our knowledge regarding the pathophysiology and prospective treatment of rare disorders. Furthermore, autologous stem cell therapy with patient-specific iPSCs shows great propensity for the minimization of immune reactions and the provision of a limitless supply of cells for transplantation. In this review, we discuss the recent updates in iPSC technology and the use of iPSCs in disease modeling and regenerative medicine.

  16. Science, technology, engineering, and mathematics (STEM) participation among college students with an autism spectrum disorder.

    Science.gov (United States)

    Wei, Xin; Yu, Jennifer W; Shattuck, Paul; McCracken, Mary; Blackorby, Jose

    2013-07-01

    Little research has examined the popular belief that individuals with an autism spectrum disorder (ASD) are more likely than the general population to gravitate toward science, technology, engineering, and mathematics (STEM) fields. This study analyzed data from the National Longitudinal Transition Study-2, a nationally representative sample of students with an ASD in special education. Findings suggest that students with an ASD had the highest STEM participation rates although their college enrollment rate was the third lowest among 11 disability categories and students in the general population. Disproportionate postsecondary enrollment and STEM participation by gender, family income, and mental functioning skills were found for young adults with an ASD. Educational policy implications are discussed.

  17. Foresight Study on Advanced Conversion Technologies of Fossil Fuels; Estudio de Prospectiva Tecnologias Avanzadas de conversion de Combustibles Fosiles

    Energy Technology Data Exchange (ETDEWEB)

    Claver, A; Cabrera, J A [Ciemat, Madrid (Spain)

    2000-07-01

    The Observatorio de Prospectiva Tecnologica Industrial (OPTI) is a Foundation supported by the Ministry of Industry and Energy, (MINER) and has a main objective a basic information and knowledge on technology evolution. This information will be accessible to the Administration and to the Companies and can be taking into account in planning and decision making of technology policies. Ciemat is member of OPTI and is the organism in charge of the actions in the Energy sector. CIEMAT has the responsibility on the realisation of the sector studies to get in three years (1998 to 2001) a foresight vision of the critical technology topics. The OPTI integrated strategic plan undertake the analysis of other seven technology sectors, with the same criteria on methodological aspects. Delphi method was used for the realization of the studies. It consisted of a survey conducted in two rounds using a questionnaire to check the experts opinion. The time frame of the studies was defined from 1999 to 2015. (Author) 17 refs.

  18. Experiences of African American Young Women in Science, Technology, Engineering, and Mathematics (STEM) Education

    Science.gov (United States)

    Kolo, Yovonda Ingram

    African American women are underrepresented in science, technology, engineering, and mathematics (STEM) fields throughout the United States. As the need for STEM professionals in the United States increases, it is important to ensure that African American women are among those professionals making valuable contributions to society. The purpose of this phenomenological study was to describe the experiences of African American young women in relation to STEM education. The research question for this study examined how experiences with STEM in K-10 education influenced African American young women's academic choices in their final years in high school. The theory of multicontextuality was used to provide the conceptual framework. The primary data source was interviews. The sample was composed of 11 African American young women in their junior or senior year in high school. Data were analyzed through the process of open coding, categorizing, and identifying emerging themes. Ten themes emerged from the answers to research questions. The themes were (a) high teacher expectations, (b) participation in extra-curricular activities, (c) engagement in group-work, (d) learning from lectures, (e) strong parental involvement, (f) helping others, (g) self-efficacy, (h) gender empowerment, (i) race empowerment, and (j) strategic recruitment practices. This study may lead to positive social change by adding to the understanding of the experiences of African American young women in STEM. By doing so, these findings might motivate other African American young women to pursue advanced STEM classes. These findings may also provide guidance to parents and educators to help increase the number of African American women in STEM.

  19. Process systems engineering issues and applications towards reducing carbon dioxide emissions through conversion technologies

    DEFF Research Database (Denmark)

    Roh, Kosan; Frauzem, Rebecca; Gani, Rafiqul

    2016-01-01

    This paper reviews issues and applications for design of sustainable carbon dioxide conversion processes, specifically through chemical conversion, and the integration of the conversion processes with other systems from a process systems engineering (PSE) view-point. Systematic and computer......-aided methods and tools for reaction network generation, processing route generation, process design/optimization, and sustainability analysis are reviewed with respect to carbon dioxide conversion. Also, the relevant gaps and opportunities are highlighted. In addition, the integration of carbon dioxide...

  20. The feasibility of using conversational agent technology to improve problem-solving and coping skills of young adults with cancer

    Directory of Open Access Journals (Sweden)

    von Friederichs-Fitzwater M

    2011-04-01

    Full Text Available Marlene M von Friederichs-Fitzwater1, Frederick J Meyers21Division of Hematology/Oncology, Internal Medicine, 2School of Medicine, University of California Davis, Sacramento, CA, USAObjective: Young adults with cancer have unique psychosocial needs and often lack the problem-solving and coping skills for effective resolution. We conducted a study to clarify these needs and then developed and tested an educational intervention to coach young adults with cancer in problem-solving and coping skills using a new conversational agent technology that uses a multi-media format to simulate face-to-face encounters.Methods: We qualitatively assessed online focus groups and chat rooms with 45 young adults with cancer and used the results to develop and test an online 15-minute educational prototype using a new conversational agent technology with 49 young adults (18–35 years of age with cancer.Results: Young adults with cancer are most concerned about reproductive issues, emotional issues, communicating with healthcare providers, and the risks and benefits of treatments. The study participants found the I-COPE prototype to be useful, easy to use, and worth recommending to others. They wanted to have more video segments about the experiences of other young adults with cancer; more video segments of actual procedures and treatments; more Internet links to information and resources; and more opportunities to interact with the conversational agent.Conclusion: New conversational agent technology is useful in coaching problem-solving and coping skills to empower young adults with cancer.Practice implications: New conversational agent technology is a useful tool in patient education and skill development, particularly among young adults.Keywords: young adult cancer patients, conversational agent technology, problem-solving, coping, self-efficacy, survivorship

  1. Dye-sensitized solar cell module realized photovoltaic and photothermal highly efficient conversion via three-dimensional printing technology

    International Nuclear Information System (INIS)

    Huang Qi-Zhang; Zhu Yan-Qing; Shi Ji-Fu; Wang Lei-Lei; Zhong Liu-Wen; Xu Gang

    2017-01-01

    Three-dimensional (3D) printing technology is employed to improve the photovoltaic and photothermal conversion efficiency of dye-sensitized solar cell (DSC) module. The 3D-printed concentrator is optically designed and improves the photovoltaic efficiency of the DSC module from 5.48% to 7.03%. Additionally, with the 3D-printed microfluidic device serving as water cooling, the temperature of the DSC can be effectively controlled, which is beneficial for keeping a high photovoltaic conversion efficiency for DSC module. Moreover, the 3D-printed microfluidic device can realize photothermal conversion with an instantaneous photothermal efficiency of 42.1%. The integrated device realizes a total photovoltaic and photothermal conversion efficiency of 49% at the optimal working condition. (paper)

  2. Dye-sensitized solar cell module realized photovoltaic and photothermal highly efficient conversion via three-dimensional printing technology

    Institute of Scientific and Technical Information of China (English)

    Qi-Zhang Huang; Yan-Qing Zhu; Ji-Fu Shi; Lei-Lei Wang; Liu-Wen Zhong; Gang Xu

    2017-01-01

    Three-dimensional (3D) printing technology is employed to improve the photovoltaic and photothermal conversion efficiency of dye-sensitized solar cell (DSC) module.The 3D-printed concentrator is optically designed and improves the photovoltaic efficiency of the DSC module from 5.48% to 7.03%.Additionally,with the 3D-printed microfluidic device serving as water cooling,the temperature of the DSC can be effectively controlled,which is beneficial for keeping a high photovoltaic conversion efficiency for DSC module.Moreover,the 3D-printed microfluidic device can realize photothermal conversion with an instantaneous photothermal efficiency of 42.1%.The integrated device realizes a total photovoltaic and photothermal conversion efficiency of 49% at the optimal working condition.

  3. Choice and Participation of Career by STEM Professionals with Sensory and Orthopedic Disabilities and the Roles of Assistive Technologies

    Science.gov (United States)

    Pacheco, Heather A.

    This is a qualitative study about sources of self-efficacy and roles of assistive technologies (AT) associated with the science, technology, engineering and mathematics (STEM) choice and participation of STEM professionals and graduate students with sensory and orthopedic disabilities. People with disabilities are underrepresented in STEM, which can be traced back along the STEM pipeline to early undergraduate participation in STEM. Little research exists, however, about pathways and factors associated with successful STEM participation for people with disabilities at any point along their trajectories. Eighteen STEM professionals and graduate students with sensory and orthopedic disabilities were interviewed for this study. Sources of self-efficacy were sought from interview transcripts, as were emergent themes associated with the types, uses and roles of AT. Findings suggest that people with sensory and orthopedic disabilities weigh sources of self-efficacy differently from white males without disabilities in STEM and more like other underrepresented minorities in STEM. Social persuasions were most frequently reported and in far more detail than other sources, suggesting that this source may be most impactful in the development of self-efficacy beliefs for this group. Additionally, findings indicate that AT is critical to the successful participation of people with sensory and orthopedic disabilities in STEM at all points along their STEM pathways. Barriers center around issues of access to full engagement in mainstream STEM classrooms and out of school opportunities as well as the impact of ill-informed perceptions about the capabilities of people with disabilities held by parents, teachers and college faculty who can act as gatekeepers along STEM pathways. Gaps in disability specialists' knowledge about STEM-specific assistive technologies, especially at the college level, are also problematic. The prevalence of mainstream public school attendance reported by

  4. Young, southern women's perceptions of STEM careers: Examining science, technology, engineering & mathematics as a gendered construct

    Science.gov (United States)

    Quinton, Jessica Elizabeth

    Career interests develop over a lifetime and tend to solidify during late adolescence and early adulthood (Lent, Brown, and Hackett, 2002). The primary purpose of the present qualitative study, which is framed in Feminist Standpoint Theory (Haraway, 1988; Harding, 2007; Naples, 2007; Richardson, 2007), is to understand how eighth-grade, young women in a suburban, public, southern, middle school the South Carolina County School District (CCSD) (pseudonym) perceive their accessibility to Science, Technology, Engineering, and Mathematics (STEM) courses and careers. The secondary purpose is to understand these young women's "perceptions and unconscious beliefs about gender in science and mathematics" and how their "perceptions and unconscious beliefs about gender" in the STEM fields may impact the careers that these young women may choose in the future (American Association of University Women, 2010, 9). Within the present study, the perceptions of young women who identified as "Interested in Science," "Somewhat Interested in Science" and "Uninterested in Science" were identified. STEM courses and careers are a major emphasis in education today. Increasing the numbers of Americans who pursue STEM careers is a government priority, as these careers will strengthen the economy (AAUW 2010). The present study reveals how young women who are highly motivated, talented students perceive STEM courses and careers and how they are influenced by their experiences, gendered messages, and knowledge of STEM careers. To analyze the data, four of Saldana's (2010) dramaturgical codes were utilized including: 1. OBJectives, or motives; 2. CONflicts the participants faced; 3. TACtics to dealing with obstacles; and 4. ATTitudes toward the setting, others, and the conflict. The InVivo Codes allowed the participants stories to emerge through the set of dramaturgical codes that allowed for viewing the girls' experience sin different ways that added depth to their stories. The young women in

  5. Differences between the Sexes among Protestant Christian Middle School Students and Their Attitudes toward Science, Technology, Engineering and Math (STEM)

    Science.gov (United States)

    Michael, Kurt Y.; Alsup, Philip R.

    2016-01-01

    Research focusing on science, technology, engineering, and math (STEM) education among conservative Protestant Christian school students is scarce. Crenshaw's intersectionality theory is examined as it pertains to religion as a group identifier. The STEM Semantic Survey was completed by 157 middle school students attending six different private…

  6. Examination of the Effects of STEM Education Integrated as a Part of Science, Technology, Society and Environment Courses

    Science.gov (United States)

    Yildirim, Bekir; Selvi, Mahmut

    2016-01-01

    This study was carried out to determine the view of prospective teachers with regard to STEM education given in Science, Technology, Society and Environment course and the effects of STEM education on prospective teachers' attitudes towards renewable energy sources and awareness of environment problems. The study was carried out in 2014-2015…

  7. Fullness of life as minimal unit: Science, technology, engineering, and mathematics (STEM) learning across the life span.

    NARCIS (Netherlands)

    Roth, W.-M.; Eijck, van M.W.

    2011-01-01

    Challenged by a National Science Foundation–funded conference, 2020 Vision: The Next Generation of STEM Learning Research, in which participants were asked to recognize science, technology, engineering, and mathematics (STEM) learning as lifelong, life-wide, and life-deep, we draw upon 20 years of

  8. Students Who Study Science, Technology, Engineering, and Mathematics (STEM) in Postsecondary Education. Stats in Brief. NCES 2009-161

    Science.gov (United States)

    Chen, Xianglei

    2009-01-01

    Rising concern about America's ability to maintain its competitive position in the global economy has renewed interest in science, technology, engineering and mathematics (STEM) education. To understand who enters into and completes undergraduate programs in STEM fields, this report examined data from three major national studies: the 1995-96…

  9. Measuring the utility of the Science, Technology, Engineering, Mathematics (STEM) Academy Measurement Tool in assessing the development of K-8 STEM academies as professional learning communities

    Science.gov (United States)

    Irish, Teresa J.

    The aim of this study was to provide insights addressing national concerns in Science, Technology, Engineering, and Mathematics (STEM) education by examining how a set of six perimeter urban K-12 schools were transformed into STEM-focused professional learning communities (PLC). The concept of a STEM Academy as a STEM-focused PLC emphasizes the development of a STEM culture where professional discourse and teaching are focused on STEM learning. The STEM Academies examined used the STEM Academy Measurement Tool and Rubric (Tool) as a catalyst for discussion and change. This Tool was developed with input from stakeholders and used for school-wide initiatives, teacher professional development and K-12 student engagement to improve STEM teaching and learning. Two primary goals of this study were to assess the levels of awareness and use of the tool by all stakeholders involved in the project and to determine how the Tool assisted in the development and advancement of these schools as STEM PLCs. Data from the STEM Academy Participant Survey was analyzed to determine stakeholders' perceptions of the Tool in terms of (i) how aware stakeholders were of the Tool, (ii) whether they participated in the use of the Tool, (iii) how the characteristics of PLCs were perceived in their schools, and finally (iv) how the awareness of the Tool influenced teachers' perceptions of the presence of PLC characteristics. Findings indicate that school faculty were aware of the Tool on a number of different levels and evidence exists that the use of the Tool assisted in the development of STEM Academies, however impact varied from school to school. Implications of this study suggest that the survey should be used for a longer period of time to gain more in-depth knowledge on teachers' perceptions of the Tool as a catalyst across time. Additional findings indicate that the process for using the Tool should be ongoing and involve the stakeholders to have the greatest impact on school culture

  10. High-flux/high-temperature solar thermal conversion: technology development and advanced applications

    Directory of Open Access Journals (Sweden)

    Romero Manuel

    2016-01-01

    Full Text Available Solar Thermal Power Plants have generated in the last 10 years a dynamic market for renewable energy industry and a pro-active networking within R&D community worldwide. By end 2015, there are about 5 GW installed in the world, most of them still concentrated in only two countries, Spain and the US, though a rapid process of globalization is taking place in the last few years and now ambitious market deployment is starting in countries like South Africa, Chile, Saudi Arabia, India, United Arab Emirates or Morocco. Prices for electricity produced by today's plants fill the range from 12 to 16 c€/kWh and they are capital intensive with investments above 4000 €/kW, depending on the number of hours of thermal storage. The urgent need to speed up the learning curve, by moving forward to LCOE below 10 c€/kWh and the promotion of sun-to-fuel applications, is driving the R&D programmes. Both, industry and R&D community are accelerating the transformation by approaching high-flux/high-temperature technologies and promoting the integration with high-efficiency conversion systems.

  11. Feasibility survey on international cooperation for high efficiency energy conversion technology in fiscal 1993

    Science.gov (United States)

    1994-03-01

    Following cooperative researches on fuel cell jointly conducted by NEDO and EGAT (Electricity Generating Authority of Thailand), the survey on international cooperation relating to high efficiency energy conversion technology was carried out for the ASEAN countries. The paper summed up the results of the survey. The study of the international cooperation is made for the following three items: a program for periodical exchange of information with EGAT, a project for cooperative research on phosphoric acid fuel cell in Indonesia, and a project for cooperative research with EGAT on electric power storage by advanced battery. In Malaysia, which is small in scale of state, part of the Ministry of Energy, Telecommunication and Posts is only in charge of the energy issue. Therefore, the situation is that they cannot answer well to many items of research/development cooperation brought in from Japan. The item of medium- and long-term developmental research in the Philippines is about the problems which are seen subsequently in the Manila metropolitan area where the problem of outage is being settled. Accordingly, it is essential to promote the cooperative research, well confirming policies and systems of the Ministry of Energy and the national electricity corporation.

  12. Alternate fuel cycle technologies, nitrate-to-oxide conversion project. Progress report, January--June 1977

    International Nuclear Information System (INIS)

    Lehmkuhl, G.D.

    1977-01-01

    Work is being done at the Rocky Flats Plant (RFP) under contract from the Savannah River Operations Office (SROO) of the U.S. Energy Research and Development Administration (ERDA) to critically analyze and evaluate existing technology for converting plutonium nitrate to plutonium oxide, and to recommend flow sheets and equipment for this process. Seven such processes were compared using an expanded process-comparison scheme. The results of the comparison differed somewhat from the initial comparison made in September, 1976. The direct calcination methods, headed by the screw calciner process, received the highest ratings when operating experience was considered with a small weighting factor. These methods are much simpler than the others. The oxalate precipitation methods, headed by the plutonium(IV) oxalate precipitation and calcination process, received highest ratings when operating experience was strongly considered. Thus, in the long term, the screw calciner or other direct-conversion methods should be developed. For a plant to be built in the short term, however, an oxalate precipitation method should be used since a larger amount of experience exists with these processes. The block flow diagrams, material balances, and equipment flow sheets for each of the seven processes compared are included in this report. A process-design criterion is being prepared for a mechanical (screw calciner) direct-denitration process, and includes process flow sheets, a material balance, a process description, equipment performance specifications, the control philosophy and specifications, the operating philosophy, and a general process layout

  13. Applications of Mesenchymal Stem Cells in Sinus Lift Augmentation as a Dental Implant Technology

    Directory of Open Access Journals (Sweden)

    Feridoun Parnia

    2018-01-01

    Full Text Available The potential application of stem cell biology in human dentistry is a new and emerging field of research. The objective of the current review was to study the efficiency of mesenchymal stem cells (MSCs in sinus lift augmentation (SLA. A literature review was performed in PubMed Central using MeSH keywords such as sinus lift, MSCs, dental implants, and augmentation. The searches involved full-text papers written in English, published in the past 10 years (2007–2017. The review included in vitro and in vivo studies on the use of MSCs in SLA. Electronic searching provided 45 titles, and among them, 8 papers were chosen as suitable based on the inclusion requirements of this review. The reviewed studies have revealed the potential of MSCs in SLA. According to these papers, stem cell therapy combined with different biomaterials may considerably improve bone regeneration in previous steps of dental implantation and may veritably lead to efficient clinical usages in the recent future. However, the identification of an ideal source of stem cells as well as long-term studies is vital to assess the success rate of this technology. Further clinical trials are also needed to approve the potential of MSCs in SLA.

  14. Women in STEM disciplines the Yfactor 2016 global report on gender in science, technology, engineering and mathematics

    CERN Document Server

    Schmuck, Claudine

    2017-01-01

    This book presents the findings of a survey that analyzes a unique set of data in science and technolog and provides a clear and simple synthesis of heterogeneous databases on the gender gap in the STEM (Science, Technology, Engineering and Mathematics) setting, helping readers understand key trends and developments. The need for more women in innovative fields, particularly with regard to STEM-based innovations, has now been broadly recognized. The book provides insights into both the education and employment of women in STEM. It investigates how the gender gap has evolved among STEM graduates and professionals around the world, drawing on specific data from public and private databases. As such, the book provides readers an understanding of how the so-called ‘leaky pipeline’ operates, and of how more women than men drop out of STEM studies and jobs by geographical area.

  15. STEMing the tide: using ingroup experts to inoculate women's self-concept in science, technology, engineering, and mathematics (STEM).

    Science.gov (United States)

    Stout, Jane G; Dasgupta, Nilanjana; Hunsinger, Matthew; McManus, Melissa A

    2011-02-01

    Three studies tested a stereotype inoculation model, which proposed that contact with same-sex experts (advanced peers, professionals, professors) in academic environments involving science, technology, engineering, and mathematics (STEM) enhances women's self-concept in STEM, attitudes toward STEM, and motivation to pursue STEM careers. Two cross-sectional controlled experiments and 1 longitudinal naturalistic study in a calculus class revealed that exposure to female STEM experts promoted positive implicit attitudes and stronger implicit identification with STEM (Studies 1-3), greater self-efficacy in STEM (Study 3), and more effort on STEM tests (Study 1). Studies 2 and 3 suggested that the benefit of seeing same-sex experts is driven by greater subjective identification and connectedness with these individuals, which in turn predicts enhanced self-efficacy, domain identification, and commitment to pursue STEM careers. Importantly, women's own self-concept benefited from contact with female experts even though negative stereotypes about their gender and STEM remained active. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

  16. Future of the Pacific: Inspiring the Next Generation of Scientists and Engineers Through Place-Based Problem-Solving Using Innovative STEM Curriculum and Technology Tools

    Science.gov (United States)

    2016-03-30

    Hands-on, Inquiry Learning Methods to Enhance STEM Learning by Engaging Students in Renewable Energy Solutions ( Research to Practice) Strand ...minorities in STEM fields, including engineering. Researchers believe that engaging, context-based engineering activities at the K-12 level could...Office ofNaval Research PD: Professional Development STEM : Science, Technology, Engineering, and Math • WIT: Women in Technology Project 3

  17. Use of nuclear space technology of direct energy conversion for terrestrial application

    International Nuclear Information System (INIS)

    Chitaykin, V.I.; Meleta, Ye.A.; Yarygin, V.I.; Mikheyev, A.S.; Tulin, S.M.

    2000-01-01

    In due time the SSC RF-IPPE exercised the scientific supervision and directly participated in the development, fabrication, space flight test and maintenance of the direct energy conversion nuclear power plants (NPP) for space application under the 'BUK' and 'TOPAZ' programs. We have used the acquired experience and the high technologies developed for the 'BUK' NPP with a thermoelectric conversion of thermal (nuclear) energy into electrical one in the development under the order of RAO 'GAZPROM' of the natural gas fired self contained thermoelectric current sources (AIT-500) and heat and electricity sources (TEP-500). These are intended for electrochemical rust protection of gas pipelines and for the electricity and heat supply to the telemetric and microwave-link systems located along the gas pipelines. Of special interest at the moment are the new developments of self contained current sources with the electrical output of ∼500 Wel for new gas pipelines being constructed under the projects such as the 'Yamal-Europe' project. The electrochemical rust protection of gas pipelines laying on unsettled and non-electrified territory of arctic regions of Russia is performed by means of the so-called Cathodic Protection Stations (CPS). Accounting for a complex of rather rigid requirements imposed by arctic operating conditions, the most attractive sources of electricity supply to the CPS are the thermoelectric heat-into-electricity converters and the generators (TEG). This paper deals with the essential results of the development, investigation and testing of unconventional TEGs using the low-temperature bismuth-tellurium thermoelectric batteries assembled together as tubular thermoelectric batteries with a radial ring geometry built into the gas-heated thermoelectric modules, which are collected to make up either the thermoelectric plants for heat and electricity supply or the self contained power sources. One of the peculiarities of these plants is the combination of

  18. Underpinning the STEM Agenda through Technological Textiles? An Exploration of Design Technology Teachers' Attitudes

    Science.gov (United States)

    Hughes, Chris; Bell, Dawne

    2011-01-01

    This paper discusses ongoing research into the role of design and technology education in emerging post industrial economies. Previous work (Hughes et al., 2010) focused on the changing characteristics of textiles technology in modern times and discussed how this could inform a design and technology curriculum related to the needs of a modern…

  19. Fiscal 1998 research report. Research on energy conversion technology using biomass resources; 1998 nendo chosa hokokusho. Biomass shigen wo genryo to suru energy henkan gijutsu ni kansuru chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Feasibility study was made on construction of the new energy production system by thermochemical conversion or combination of thermochemical and biological conversions of agricultural, fishery and organic waste system biomass resources. This report first outlines types and characteristics of biomass over the world, proposes the classification method of biomass from the viewpoint of biomass energy use, and shows the introduction scenario of biomass energy. The energy potential is calculated of agricultural waste, forestry waste and animal waste as the most promising biomass energy resources, and the biomass energy potential of energy plantation is estimated. The present and future of biochemical energy conversion technologies are viewed. The present and future of thermochemical energy conversion technologies are also viewed. Through evaluation of every conversion technology, the difference in feature between each conversion technology was clarified, and the major issues for further R and D were showed. (NEDO)

  20. Technologies, Multitasking, and Driving: Attending to and Preparing for a Mobile Phone Conversation in a Car

    Science.gov (United States)

    Haddington, Pentti; Rauniomaa, Mirka

    2011-01-01

    This article investigates mobile phone calls initiated or received by drivers and passengers in cars and focuses on the participants' actions before the telephone conversation proper. Drawing on video-recorded data of real driving situations, and building on conversation analysis and multimodal interaction analysis, this article discusses how…

  1. Image Format Conversion to DICOM and Lookup Table Conversion to Presentation Value of the Japanese Society of Radiological Technology (JSRT) Standard Digital Image Database.

    Science.gov (United States)

    Yanagita, Satoshi; Imahana, Masato; Suwa, Kazuaki; Sugimura, Hitomi; Nishiki, Masayuki

    2016-01-01

    Japanese Society of Radiological Technology (JSRT) standard digital image database contains many useful cases of chest X-ray images, and has been used in many state-of-the-art researches. However, the pixel values of all the images are simply digitized as relative density values by utilizing a scanned film digitizer. As a result, the pixel values are completely different from the standardized display system input value of digital imaging and communications in medicine (DICOM), called presentation value (P-value), which can maintain a visual consistency when observing images using different display luminance. Therefore, we converted all the images from JSRT standard digital image database to DICOM format followed by the conversion of the pixel values to P-value using an original program developed by ourselves. Consequently, JSRT standard digital image database has been modified so that the visual consistency of images is maintained among different luminance displays.

  2. Direct conversion of human pluripotent stem cells into cranial motor neurons using a piggyBac vector

    Directory of Open Access Journals (Sweden)

    Riccardo De Santis

    2018-05-01

    Full Text Available Human pluripotent stem cells (PSCs are widely used for in vitro disease modeling. One of the challenges in the field is represented by the ability of converting human PSCs into specific disease-relevant cell types. The nervous system is composed of a wide variety of neuronal types with selective vulnerability in neurodegenerative diseases. This is particularly relevant for motor neuron diseases, in which different motor neurons populations show a different susceptibility to degeneration. Here we developed a fast and efficient method to convert human induced Pluripotent Stem Cells into cranial motor neurons of the branchiomotor and visceral motor subtype. These populations represent the motor neuron subgroup that is primarily affected by a severe form of amyotrophic lateral sclerosis with bulbar onset and worst prognosis. This goal was achieved by stable integration of an inducible vector, based on the piggyBac transposon, allowing controlled activation of Ngn2, Isl1 and Phox2a (NIP. The NIP module effectively produced electrophysiologically active cranial motor neurons. Our method can be easily extended to PSCs carrying disease-associated mutations, thus providing a useful tool to shed light on the cellular and molecular bases of selective motor neuron vulnerability in pathological conditions. Keywords: Spinal motor neuron, Cranial motor neuron, Induced pluripotent stem cells, Amyotrophic lateral sclerosis, Phox2a, piggyBac

  3. Capture, transformation and conversion of the solar energy by the technologies of concentration; Captation, transformation et conversion de l'energie solaire par les technologies a concentration

    Energy Technology Data Exchange (ETDEWEB)

    Ferriere, A.; Flamant, G

    2003-07-01

    The specificities of the solar technologies at concentration are: high energy efficiency with increasing possibilities and the possibility of storage the solar energy by heat for a local and short dated utilization or by chemical storage (hydrogen for instance) for a delayed utilization or far from the capture area. This document takes stock on the concentration solar techniques, the electric power production by concentrated solar energy and the performance of concentrated solar plants, the industrial american experience of the SEGS plants, the hydrogen production by concentrated solar energy and discusses the scientific and technological locks. (A.L.B.)

  4. Sustainable resource recovery and energy conversion processes using microbial electrochemical technologies

    Science.gov (United States)

    Yates, Matthew D.

    Microbial Electrochemical Technologies (METs) are emerging technological platforms for the conversion of waste into usable products. METs utilize naturally occurring bacteria, called exoelectrogens, capable of transferring electrons to insoluble terminal electron acceptors. Electron transfer processes in the exoelectrogen Geobacter sulfurreducens were exploited here to develop sustainable processes for synthesis of industrially and socially relevant end products. The first process examined was the removal of soluble metals from solution to form catalytic nanoparticles and nanoporous structures. The second process examined was the biocatalytic conversion of electrons into hydrogen gas using electrons supplied directly to an electrode. Nanoparticle formation is desirable because materials on the nanoscale possess different physical, optical, electronic, and mechanical properties compared to bulk materials. In the first process, soluble palladium was used to form catalytic palladium nanoparticles using extracellular electron transfer (EET) processes of G. sulfurreducens, typically the dominant member of mixedculture METs. Geobacter cells reduced the palladium extracellularly using naturally produced pili, which provided extracellular adsorption and reduction sites to help delay the diffusion of soluble metals into the cell. The extracellular reduction prevented cell inactivation due to formation of intracellular particles, and therefore the cells could be reused in multiple palladium reduction cycles. A G. sulfurreducens biofilm was next investigated as a biotemplate for the formation of a nanoporous catalytic palladium structure. G. sulfurreducens biofilms have a dense network of pili and extracellular cytochromes capable of high rates of electron transfer directly to an electrode surface. These pili and cytochromes provide a dense number of reduction sites for nanoparticle formation without the need for any synthetic components. The cells within the biofilm also can

  5. Basic and applied research related to the technology of space energy conversion systems, 1982 - 1983

    Science.gov (United States)

    Hertzberg, A.

    1983-01-01

    Topics on solar energy conversion concepts and applications are discussed. An overview of the current status and future utilization of radiation receivers for electrical energy generation, liquid droplet radiation systems, and liquid droplet heat exchangers is presented.

  6. Gas Turbine Energy Conversion Systems for Nuclear Power Plants Applicable to LiFTR Liquid Fluoride Thorium Reactor Technology

    Science.gov (United States)

    Juhasz, Albert J.

    2014-01-01

    This panel plans to cover thermal energy and electric power production issues facing our nation and the world over the next decades, with relevant technologies ranging from near term to mid-and far term.Although the main focus will be on ground based plants to provide baseload electric power, energy conversion systems (ECS) for space are also included, with solar- or nuclear energy sources for output power levels ranging tens of Watts to kilo-Watts for unmanned spacecraft, and eventual mega-Watts for lunar outposts and planetary surface colonies. Implications of these technologies on future terrestrial energy systems, combined with advanced fracking, are touched upon.Thorium based reactors, and nuclear fusion along with suitable gas turbine energy conversion systems (ECS) will also be considered by the panelists. The characteristics of the above mentioned ECS will be described, both in terms of their overall energy utilization effectiveness and also with regard to climactic effects due to exhaust emissions.

  7. Technology Development Program for an Advanced Potassium Rankine Power Conversion System Compatible with Several Space Reactor Designs

    Energy Technology Data Exchange (ETDEWEB)

    Yoder, G.L.

    2005-10-03

    This report documents the work performed during the first phase of the National Aeronautics and Space Administration (NASA), National Research Announcement (NRA) Technology Development Program for an Advanced Potassium Rankine Power Conversion System Compatible with Several Space Reactor Designs. The document includes an optimization of both 100-kW{sub e} and 250-kW{sub e} (at the propulsion unit) Rankine cycle power conversion systems. In order to perform the mass optimization of these systems, several parametric evaluations of different design options were investigated. These options included feed and reheat, vapor superheat levels entering the turbine, three different material types, and multiple heat rejection system designs. The overall masses of these Nb-1%Zr systems are approximately 3100 kg and 6300 kg for the 100- kW{sub e} and 250-kW{sub e} systems, respectively, each with two totally redundant power conversion units, including the mass of the single reactor and shield. Initial conceptual designs for each of the components were developed in order to estimate component masses. In addition, an overall system concept was presented that was designed to fit within the launch envelope of a heavy lift vehicle. A technology development plan is presented in the report that describes the major efforts that are required to reach a technology readiness level of 6. A 10-year development plan was proposed.

  8. Analysis of an Interactive Technology Supported Problem-Based Learning STEM Project Using Selected Learning Sciences Interest Areas (SLSIA)

    Science.gov (United States)

    Kumar, David Devraj

    2017-01-01

    This paper reports an analysis of an interactive technology-supported, problem-based learning (PBL) project in science, technology, engineering and mathematics (STEM) from a Learning Sciences perspective using the Selected Learning Sciences Interest Areas (SLSIA). The SLSIA was adapted from the "What kinds of topics do ISLS [International…

  9. Progressing science, technology, engineering, and math (STEM) education in North Dakota with near-space ballooning

    Science.gov (United States)

    Saad, Marissa Elizabeth

    The United States must provide quality science, technology, engineering, and math (STEM) education in order to maintain a leading role in the global economy. Numerous initiatives have been established across the United States that promote and encourage STEM education within the middle school curriculum. Integrating active learning pedagogy into instructors' lesson plans will prepare the students to think critically - a necessary skill for the twenty first century. This study integrated a three-week long Near Space Balloon project into six eighth grade Earth Science classes from Valley Middle School in Grand Forks, North Dakota. It was hypothesized that after the students designed, constructed, launched, and analyzed their payload experiments, they would have an increased affinity for high school science and math classes. A pre- and post-survey was distributed to the students (n=124), before and after the project to analyze how effective this engineering and space mission was regarding high school STEM interests. The surveys were statistically analyzed, comparing means by the Student's t-Test, specifically the Welch-Satterthwaite test. Female students displayed a 57.1% increase in math and a 63.6% increase in science; male students displayed a 46.6% increase in science and 0% increase in math. Most Likert-scale survey questions experienced no statistically significant change, supporting the null hypothesis. The only survey question that supported the hypothesis was, "I Think Engineers Work Alone," which experienced a 0.24% decrease in student understanding. The results suggest that integrating a three-week long Near Space Balloon project into middle school curricula will not directly influence the students' excitement to pursue STEM subjects and careers. An extensive, yearlong ballooning mission is recommended so that it can be integrated with multiple core subjects. Using such an innovative pedagogy method as with this balloon launch will help students master the

  10. Harnessing Technology to Improve Formative Assessment of Student Conceptions in STEM: Forging a National Network

    Science.gov (United States)

    Haudek, Kevin C.; Kaplan, Jennifer J.; Knight, Jennifer; Long, Tammy; Merrill, John; Munn, Alan; Nehm, Ross; Smith, Michelle; Urban-Lurain, Mark

    2011-01-01

    Concept inventories, consisting of multiple-choice questions designed around common student misconceptions, are designed to reveal student thinking. However, students often have complex, heterogeneous ideas about scientific concepts. Constructed-response assessments, in which students must create their own answer, may better reveal students’ thinking, but are time- and resource-intensive to evaluate. This report describes the initial meeting of a National Science Foundation–funded cross-institutional collaboration of interdisciplinary science, technology, engineering, and mathematics (STEM) education researchers interested in exploring the use of automated text analysis to evaluate constructed-response assessments. Participants at the meeting shared existing work on lexical analysis and concept inventories, participated in technology demonstrations and workshops, and discussed research goals. We are seeking interested collaborators to join our research community. PMID:21633063

  11. Combining Induced Pluripotent Stem Cells and Genome Editing Technologies for Clinical Applications.

    Science.gov (United States)

    Chang, Chia-Yu; Ting, Hsiao-Chien; Su, Hong-Lin; Jeng, Jing-Ren

    2018-01-01

    In this review, we introduce current developments in induced pluripotent stem cells (iPSCs), site-specific nuclease (SSN)-mediated genome editing tools, and the combined application of these two novel technologies in biomedical research and therapeutic trials. The sustainable pluripotent property of iPSCs in vitro not only provides unlimited cell sources for basic research but also benefits precision medicines for human diseases. In addition, rapidly evolving SSN tools efficiently tailor genetic manipulations for exploring gene functions and can be utilized to correct genetic defects of congenital diseases in the near future. Combining iPSC and SSN technologies will create new reliable human disease models with isogenic backgrounds in vitro and provide new solutions for cell replacement and precise therapies.

  12. CRADA Final Report for CRADA Number NFE-10-02991 "Development and Commercialization of Alternative Carbon Precursors and Conversion Technologies"

    Energy Technology Data Exchange (ETDEWEB)

    Norris, Rober [ORNL; Paulauskas, Felix [ORNL; Naskar, Amit [ORNL; Kaufman, Michael [ORNL; Yarborough, Ken [ORNL; Derstine, Chris [The Dow Chemical Company

    2013-10-01

    The overall objective of the collaborative research performed by the Oak Ridge National Laboratory (ORNL) and the Dow Chemical Company under this Cooperative Research And Development Agreement (CRADA NFE-10-02991) was to develop and establish pathways to commercialize new carbon fiber precursor and conversion technology. This technology is to produce alternative polymer fiber precursor formulations as well as scaled energy-efficient advanced conversion technology to enable continuous mode conversion to obtain carbonized fibers that are technically and economically viable in industrial markets such as transportation, wind energy, infrastructure and oil drilling applications. There have been efforts in the past to produce a low cost carbon fiber. These attempts have to be interpreted against the backdrop of the market needs at the time, which were strictly military aircraft and high-end aerospace components. In fact, manufacturing costs have been reduced from those days to current practice, where both process optimization and volume production have enabled carbon fiber to become available at prices below $20/lb. However, the requirements of the lucrative aerospace market limits further price reductions from current practice. This approach is different because specific industrial applications are targeted, most specifically wind turbine blade and light vehicle transportation, where aircraft grade carbon fiber is not required. As a result, researchers are free to adjust both manufacturing process and precursor chemistry to meet the relaxed physical specifications at a lower cost. This report documents the approach and findings of this cooperative research in alternative precursors and advanced conversion for production of cost-effective carbon fiber for energy missions. Due to export control, proprietary restrictions, and CRADA protected data considerations, specific design details and processing parameters are not included in this report.

  13. Technologies and methods used for the detection, enrichment and characterization of cancer stem cells.

    Science.gov (United States)

    Williams, Anthony; Datar, Ram; Cote, Richard

    2010-01-01

    Cancer stem cells (CSCs) represent a subclass of tumour cells with the ability for self-renewal, production of differentiated progeny, prolonged survival, resistance to damaging therapeutic agents, and anchorage-independent survival, which together make this population effectively equipped to metastasize, invade and colonize secondary tissues in the face of therapeutic intervention. In recent years, investigators have increasingly focused on the characterization of CSCs to better understand the mechanisms that govern malignant disease progression in an effort to develop more effective, targeted therapeutic agents. The primary obstacle to the study of CSCs, however, is their rarity. Thus, the study of CSCs requires the use of sensitive and efficient technologies for their enrichment and detection. This review discusses technologies and methods that have been adapted and used to isolate and characterize CSCs to date, as well as new potential directions for the enhanced enrichment and detection of CSCs. While the technologies used for CSC enrichment and detection have been useful thus far for their characterization, each approach is not without limitations. Future studies of CSCs will depend on the enhanced sensitivity and specificity of currently available technologies, and the development of novel technologies for increased detection and enrichment of CSCs.

  14. Vectors to Increase Production Efficiency of Inducible Pluripotent Stem Cell (iPSC) | NCI Technology Transfer Center | TTC

    Science.gov (United States)

    This invention describes the discovery that specific p53 isoform increase the number of inducible pluripotent stem cells (iPS). It is known that the activity of p53 regulates the self-renewal and pluripotency of normal and cancer stem cells, and also affects re-programming efficiency of iPS cells. This p53 isoform-based technology provides a more natural process of increasing iPS cell production than previous methods of decreasing p53. NCI seeks licensees for this technology.

  15. Concise Review: Microfluidic Technology Platforms: Poised to Accelerate Development and Translation of Stem Cell-Derived Therapies

    Science.gov (United States)

    Titmarsh, Drew M.; Chen, Huaying; Glass, Nick R.; Cooper-White, Justin J.

    2014-01-01

    Stem cells are a powerful resource for producing a variety of cell types with utility in clinically associated applications, including preclinical drug screening and development, disease and developmental modeling, and regenerative medicine. Regardless of the type of stem cell, substantial barriers to clinical translation still exist and must be overcome to realize full clinical potential. These barriers span processes including cell isolation, expansion, and differentiation; purification, quality control, and therapeutic efficacy and safety; and the economic viability of bioprocesses for production of functional cell products. Microfluidic systems have been developed for a myriad of biological applications and have the intrinsic capability of controlling and interrogating the cellular microenvironment with unrivalled precision; therefore, they have particular relevance to overcoming such barriers to translation. Development of microfluidic technologies increasingly utilizes stem cells, addresses stem cell-relevant biological phenomena, and aligns capabilities with translational challenges and goals. In this concise review, we describe how microfluidic technologies can contribute to the translation of stem cell research outcomes, and we provide an update on innovative research efforts in this area. This timely convergence of stem cell translational challenges and microfluidic capabilities means that there is now an opportunity for both disciplines to benefit from increased interaction. PMID:24311699

  16. Conversion of adult human peripheral blood mononuclear cells into induced neural stem cell by using episomal vectors

    Directory of Open Access Journals (Sweden)

    Xihe Tang

    2016-03-01

    Full Text Available Human neural stem cells (NSCs hold great promise for research and therapy in neural diseases. Many studies have shown direct induction of NSCs from human fibroblasts, which require an invasive skin biopsy and a prolonged period of expansion in cell culture prior to use. Peripheral blood (PB is routinely used in medical diagnoses, and represents a noninvasive and easily accessible source of cells. Here we show direct derivation of NSCs from adult human PB mononuclear cells (PB-MNCs by employing episomal vectors for transgene delivery. These induced NSCs (iNSCs can expand more than 60 passages, can exhibit NSC morphology, gene expression, differentiation potential, and self-renewing capability and can give rise to multiple functional neural subtypes and glial cells in vitro. Furthermore, the iNSCs carry a specific regional identity and have electrophysiological activity upon differentiation. Our findings provide an easily accessible approach for generating human iNSCs which will facilitate disease modeling, drug screening, and possibly regenerative medicine.

  17. Direct Conversion of Human Umbilical Cord Blood into Induced Neural Stem Cells with SOX2 and HMGA2.

    Science.gov (United States)

    Kim, Jae-Jun; Shin, Ji-Hee; Yu, Kyung-Rok; Lee, Byung-Chul; Kang, Insung; Lee, Jin Young; Kim, Da-Hyun; Seo, Yoojin; Kim, Hyung-Sik; Choi, Soon Won; Kang, Kyung-Sun

    2017-11-30

    Recent advances have shown the direct reprogramming of mouse and human fibroblasts into induced neural stem cells (iNSCs) without passing through an intermediate pluripotent state. Thus, direct reprogramming strategy possibly provides a safe and homogeneous cellular platform. However, the applications of iNSCs for regenerative medicine are limited by the restricted availability of cell sources. Human umbilical cord blood (hUCB) cells hold great potential in that immunotyped hUCB units can be immediately obtained from public banks. Moreover, hUCB samples do not require invasive procedures during collection or an extensive culture period prior to reprogramming. We recently reported that somatic cells can be directly converted into iNSCs with high efficiency and a short turnaround time. Here, we describe the detailed method for the generation of iNSCs derived from hUCB (hUCB iNSCs) using the lineage-specific transcription factors SOX2 and HMGA2. The protocol for deriving iNSC-like colonies takes 1∼2 weeks and establishment of homogenous hUCB iNSCs takes additional 2 weeks. Established hUCB iNSCs are clonally expandable and multipotent producing neurons and glia. Our study provides an accessible method for generating hUCB iNSCs, contributing development of in vitro neuropathological model systems.

  18. Evaluation of environmental-control technologies for commercial nuclear fuel-conversion (UF6) facilities

    International Nuclear Information System (INIS)

    Perkins, B.L.

    1982-10-01

    At present in the United States, there are two commercial conversion facilities. These facilities process uranium concentrate into UF 6 for shipment to the enrichment facilities. One conversion facility uses a dry hydrofluor process, whereas the other facility uses a process known as the wet solvent extraction-fluorination process. Because of the different processes used in the two plants, waste characteristics, quantities, and treatment practices differ at each facility. Wastes and effluent streams contain impurities found in the concentrate (such as uranium daughters, vanadium, molybdenum, selenium, arsenic, and ammonia) and process chemicals used in the circuit (including fluorine, nitrogen, and hydrogen), as well as small quantities of uranium. Studies of suitable disposal options for the solid wastes and sludges generated at the facilities and the long-term effects of emissions to the ambient environment are needed. 30 figures, 34 tables

  19. The alkali metal thermoelectric converter /AMTEC/ - A new direct energy conversion technology for aerospace power

    Science.gov (United States)

    Bankston, C. P.; Cole, T.; Jones, R.; Ewell, R.

    1982-01-01

    A thermally regenerative electrochemical device for the direct conversion of heat to electrical energy, the alkali metal thermoelectric converter (AMTEC), is characterized by potential efficiencies on the order of 15-40% and possesses no moving parts, making it a candidate for space power system applications. Device conversion efficiency is projected on the basis of experimental voltage vs current curves exhibiting power densities of 0.7 W/sq cm and measured electrode efficiencies of up to 40%. Preliminary radiative heat transfer measurements presented may be used in an investigation of methods for the reduction of AMTEC parasitic radiation losses. AMTEC assumes heat input and rejection temperatures of 900-1300 K and 400-800 K, respectively. The working fluid is liquid sodium, and the porous electrode employed is of molybdenum.

  20. Cost update technology, safety, and costs of decommissioning a reference uranium hexafluoride conversion plant

    International Nuclear Information System (INIS)

    Miles, T.L.; Liu, Y.

    1995-08-01

    The purpose of this study is to update the cost estimates developed in a previous report, NUREG/CR-1757 (Elder 1980) for decommissioning a reference uranium hexafluoride conversion plant from the original mid-1981 dollars to values representative of January 1993. The cost updates were performed by using escalation factors derived from cost index trends over the past 11.5 years. Contemporary price quotes wee used for costs that have increased drastically or for which is is difficult to find a cost trend. No changes were made in the decommissioning procedures or cost element requirements assumed in NUREG/CR-1757. This report includes only information that was changed from NUREG/CR-1757. Thus, for those interested in detailed descriptions and associated information for the reference uranium hexafluoride conversion plant, a copy of NUREG/CR-1757 will be needed

  1. Low conversion loss 94 GHz and 188 GHz doublers in InP DHBT technology

    DEFF Research Database (Denmark)

    Zhurbenko, Vitaliy; Johansen, Tom Keinicke; Squartecchia, Michele

    2017-01-01

    An Indium Phosphide (InP) Double Heterojunction Bipolar Transistor (DHBT) process has been utilized to design two doublers to cover the 94 GHz and 188 GHz bands. The 94 GHz doubler employs 4-finger DHBTs and provides conversion loss of 2 dB. A maximum output power of nearly 3 dBm is measured whil...... operate over a broad bandwidth. The total circuit area of each chip is 1.41 mm2....

  2. Career Advancement Outcomes in Academic Science, Technology, Engineering and Mathematics (STEM): Gender, Mentoring Resources, and Homophily

    Science.gov (United States)

    Lee, Sang Eun

    This dissertation examines gender differences in career advancement outcomes among academic science, technology, engineering and mathematics (STEM) scientists. In particular, this research examines effects of gender, PhD advisors and postdoctoral supervisors mentoring resources and gender homophily in the mentoring dyads on the career advancement outcomes at early career stages. Female academic scientists have disadvantages in the career progress in the academic STEM. They tend to fall behind throughout their career paths and to leave the field compared to their male colleagues. Researchers have found that gender differences in the career advancement are shaped by gender-biased evaluations derived from gender stereotypes. Other studies demonstrate the positive impacts of mentoring and gender homophily in the mentoring dyads. To add greater insights to the current findings of female academic scientists' career disadvantages, this dissertation investigates comprehensive effects of gender, mentoring, and gender homophily in the mentoring dyads on female scientists' career advancement outcomes in academic science. Based on the Status Characteristics Theory, the concept of mentoring, Social Capital Theory, and Ingroup Bias Theory, causal path models are developed to test direct and indirect effects of gender, mentoring resources, and gender homophily on STEM faculty's career advancement. The research models were tested using structural equation modeling (SEM) with data collected from a national survey, funded by the National Science Foundation, completed in 2011 by tenured and tenure-track academic STEM faculty from higher education institutions in the United States. Findings suggest that there is no gender difference in career advancement controlling for mentoring resources and gender homophily in the mentoring dyads and other factors including research productivity and domestic caregiving responsibilities. Findings also show that the positive relationship between

  3. OPTIMIZED WTE CONVERSION OF MUNICIPAL SOLID WASTE IN SHANGHAI APPLYING THERMOCHEMICAL TECHNOLOGIES

    OpenAIRE

    Dai, Siyang

    2016-01-01

    Thermochemical technologies have been proven effective in treating municipal solid waste (MSW) for many years. China, with a rapid increase of MSW, plans to implement more environmental friendly ways to treat MSW than landfill, which treats about 79 % of total MSW currently. The aim of this master thesis was to find out a suitable thermochemical technology to treat MSW in Shanghai, China. Several different thermochemical technologies are compared in this thesis and plasma gasification was sel...

  4. Microencapsulation Technology: A Powerful Tool for Integrating Expansion and Cryopreservation of Human Embryonic Stem Cells

    Science.gov (United States)

    Malpique, Rita; Brito, Catarina; Jensen, Janne; Bjorquist, Petter; Carrondo, Manuel J. T.; Alves, Paula M.

    2011-01-01

    The successful implementation of human embryonic stem cells (hESCs)-based technologies requires the production of relevant numbers of well-characterized cells and their efficient long-term storage. In this study, cells were microencapsulated in alginate to develop an integrated bioprocess for expansion and cryopreservation of pluripotent hESCs. Different three-dimensional (3D) culture strategies were evaluated and compared, specifically, microencapsulation of hESCs as: i) single cells, ii) aggregates and iii) immobilized on microcarriers. In order to establish a scalable bioprocess, hESC-microcapsules were cultured in stirred tank bioreactors. The combination of microencapsulation and microcarrier technology resulted in a highly efficient protocol for the production and storage of pluripotent hESCs. This strategy ensured high expansion ratios (an approximately twenty-fold increase in cell concentration) and high cell recovery yields (>70%) after cryopreservation. When compared with non-encapsulated cells, cell survival post-thawing demonstrated a three-fold improvement without compromising hESC characteristics. Microencapsulation also improved the culture of hESC aggregates by protecting cells from hydrodynamic shear stress, controlling aggregate size and maintaining cell pluripotency for two weeks. This work establishes that microencapsulation technology may prove a powerful tool for integrating the expansion and cryopreservation of pluripotent hESCs. The 3D culture strategy developed herein represents a significant breakthrough towards the implementation of hESCs in clinical and industrial applications. PMID:21850261

  5. Integration and Exploitation of Advanced Visualization and Data Technologies to Teach STEM Subjects

    Science.gov (United States)

    Brandon, M. A.; Garrow, K. H.

    2014-12-01

    We live in an age where the volume of content available online to the general public is staggering. Integration of data from new technologies gives us amazing educational opportunities when appropriate narratives are provided. We prepared a distance learning credit bearing module that showcased many currently available data sets and state of the art technologies. It has been completed by many thousands of students with good feedback. Module highlights were the wide ranging and varied online activities which taught a wide range of STEM content. For example: it is well known that on Captain Scott's Terra Nova Expedition 1910-13, three researchers completed the "the worst journey in the world" to study emperor penguins. Using their primary records and clips from location filmed television documentaries we can tell their story and the reasons why it was important. However using state of the art content we can go much further. Using satellite data students can trace the path the researchers took and observe the penguin colony that they studied. Linking to modern Open Access literature students learn how they can estimate the numbers of animals in this and similar locations. Then by linking to freely available data from Antarctic Automatic Weather Stations students can learn quantitatively about the climatic conditions the animals are enduring in real time. They can then download and compare this with the regional climatic record to see if their observations are what could be expected. By considering the environment the penguins live in students can be taught about the evolutionary and behavioural adaptations the animals have undergone to survive. In this one activity we can teach a wide range of key learning points in an engaging and coherent way. It opened some students' eyes to the range of possibilities available to learn about our, and other planets. The addition and integration of new state of the art techniques and data sets only increases the opportunities to

  6. Technology, Safety and Costs of Decommissioning a Reference Uranium Hexafluoride Conversion Plant

    Energy Technology Data Exchange (ETDEWEB)

    Elder, H. K.

    1981-10-01

    Safety and cost information is developed for the conceptual decommissioning of a commercial uranium hexafluoride conversion (UF{sub 6}) plant. Two basic decommissioning alternatives are studied to obtain comparisons between cost and safety impacts: DECON, and passive SAFSTOR. A third alternative, DECON of the plant and equipment with stabilization and long-term care of lagoon wastes. is also examined. DECON includes the immediate removal (following plant shutdown) of all radioactivity in excess of unrestricted release levels, with subsequent release of the site for public use. Passive SAFSTOR requires decontamination, preparation, maintenance, and surveillance for a period of time after shutdown, followed by deferred decontamination and unrestricted release. DECON with stabilization and long-term care of lagoon wastes (process wastes generated at the reference plant and stored onsite during plant operation} is also considered as a decommissioning method, although its acceptability has not yet been determined by the NRC. The decommissioning methods assumed for use in each decommissioning alternative are based on state-of-the-art technology. The elapsed time following plant shutdown required to perform the decommissioning work in each alternative is estimated to be: for DECON, 8 months; for passive SAFSTOR, 3 months to prepare the plant for safe storage and 8 months to accomplish deferred decontamination. Planning and preparation for decommissioning prior to plant shutdown is estimated to require about 6 months for either DECON or passive SAFSTOR. Planning and preparation prior to starting deferred decontamination is estimated to require an additional 6 months. OECON with lagoon waste stabilization is estimated to take 6 months for planning and about 8 months to perform the decommissioning work. Decommissioning cost, in 1981 dollars, is estimated to be $5.91 million for OECON. For passive SAFSTOR, preparing the facility for safe storage is estimated to cost $0

  7. Sustainable energy conversion for electricity and coproducts principles, technologies, and equipment

    CERN Document Server

    Rao, Ashok

    2015-01-01

    Provides an introduction to energy systems going on to describe various forms of energy sources Provides a comprehensive and a fundamental approach to the study of sustainable fuel conversion for the generation of electricity and for coproducing synthetic fuels and chemicals Covers the underlying principles of physics and their application to engineering including thermodynamics of combustion and power cycles, fluid flow, heat transfer, and mass transfer Details the coproduction of fuels and chemicals including key equipment used in synthesis and specific examples of coproduction in integrated

  8. Development of high-level radioactive waste treatment and conversion technologies 'Dry decontamination technology development for highly radioactive contaminants'

    International Nuclear Information System (INIS)

    Oh, Won Zin; Lee, K. W.; Won, H. J.; Jung, C. J.; Choi, W. K.; Kim, G. N.; Moon, J. K.

    2001-04-01

    The followings were studied through the project entitled 'Dry Decontamination Technology Development for Highly Radioactive Contaminants'. 1.Contaminant Characteristics Analysis of Domestic Nuclear Fuel Cycle Projects(NFCP) and Applicability Study of the Unit Dry-Decontamination Techniques A. Classification of contaminated equipments and characteristics analysis of contaminants B. Applicability study of the unit dry-decontamination techniques 2.Performance Evaluation of Unit Dry Decontamination Technique A. PFC decontamination technique B. CO2 decontamination technique C. Plasma decontamination technique 3.Development of Residual Radiation Assessment Methodology for High Radioactive Facility Decontamination A. Development of radioactive nuclide diffusion model on highly radioactive facility structure B. Obtainment of the procedure for assessment of residual radiation dose 4.Establishment of the Design Concept of Dry Decontamination Process Equipment Applicable to Highly Radioactive Contaminants 5.TRIGA soil unit decontamination technology development A. Development of soil washing and flushing technologies B. Development of electrokinetic soil decontamination technology

  9. Gender Gap in Science, Technology, Engineering, and Mathematics (STEM): Current Knowledge, Implications for Practice, Policy, and Future Directions

    Science.gov (United States)

    Wang, Ming-Te; Degol, Jessica L.

    2017-01-01

    Although the gender gap in math course-taking and performance has narrowed in recent decades, females continue to be underrepresented in math-intensive fields of Science, Technology, Engineering, and Mathematics (STEM). Career pathways encompass the ability to pursue a career as well as the motivation to employ that ability. Individual differences…

  10. The Implementation of Integrated Science Technology, Engineering and Mathematics (STEM) Instruction Using Robotics in the Middle School Science Classroom

    Science.gov (United States)

    Ntemngwa, Celestin; Oliver, J. Steve

    2018-01-01

    The research study reported here was conducted to investigate the implementation of integrated STEM lessons within courses that have a single subject science focus. The purpose also included development of a pedagogical theory. This technology-based teaching was conceptualized by school administrators and teachers in order to provide middle school…

  11. Effect of Makerspace Professional Development Activities on Elementary and Middle School Educator Perceptions of Integrating Technologies with STEM (Science, Technology, Engineering, Mathematics)

    Science.gov (United States)

    Miller, Jennifer Renea

    2016-01-01

    This study investigated a Makerspace professional development program, the Makers' Guild, provided to teachers within north Texas over the course of a semester. The research employed a constructionist approach delivered via 2D and 3D technologies during STEM instructional activities within a creative space. Participants reported statistically…

  12. Tracking the conversion of nitrogen during pyrolysis of antibiotic mycelial fermentation residues using XPS and TG-FTIR-MS technology

    International Nuclear Information System (INIS)

    Zhu, Xiangdong; Yang, Shijun; Wang, Liang; Liu, Yuchen; Qian, Feng; Yao, Wenqing; Zhang, Shicheng; Chen, Jianmin

    2016-01-01

    Antibiotic mycelial fermentation residues (AMFRs), which are emerging solid pollutants, have been recognized as hazardous waste in China since 2008. Nitrogen (N), which is an environmental sensitivity element, is largely retained in AMFR samples derived from fermentation substrates. Pyrolysis is a promising technology for the treatment of solid waste. However, the outcomes of N element during the pyrolysis of AMFRs are still unknown. In this study, the conversion of N element during the pyrolysis of AMFRs was tracked using XPS (X-ray photoelectron spectroscopy) and online TG-FTIR-MS (Thermogravimetry-Fourier transform infrared-Mass spectrometry) technology. In the AMFR sample, organic amine-N, pyrrolic-N, protein-N, pyridinic-N, was the main N-containing species. XPS results indicated that pyrrolic-N and pyridinic-N were retained in the AMFR-derived pyrolysis char. More stable species, such as N-oxide and quaternary-N, were also produced in the char. TG-FTIR-MS results indicated that NH_3 and HCN were the main gaseous species, and their contents were closely related to the contents of amine-N and protein-N, and pyrrolic-N and pyridinic-N of AMFRs, respectively. Increases in heating rate enhanced the amounts of NH_3 and HCN, but had less of an effect on the degradation degree of AMFRs. N-containing organic compounds, including amine-N, nitrile-N and heterocyclic-N, were discerned from the AMFR pyrolysis process. Their release range was extended with increasing of heating rate and carbon content of AMFR sample. This work will help to take appropriate measure to reduce secondary pollution from the treatment of AMFRs. - Highlights: • Hazardous AMFR material was treated by slow pyrolysis reaction. • TG-FTIR-MS were used to study the N conversion for pyrolysis gas and bio-oil. • NH_3 and HCN were observed as the main N-containing gas species. • XPS were used to study the N conversion for pyrolysis char. • Stable species, such as N-oxide and quaternary-N, were

  13. Circulating fluidized-bed technologies for the conversion of biomass into energy

    International Nuclear Information System (INIS)

    Greil, C.; Hirschfelder, H.

    1995-01-01

    The paper introduces circulating fluidized-bed (CFB) combustion and CFB gasification. CFB combustion units are state-of-the-art and have proven their ability to convert biomass into power and/or steam. The existing units and projects in developing countries are discussed as examples of conventional technology. To illustrate advanced technologies, CFB gasification is discussed. Important process parameters of plants already in operation or under construction in developed countries are shown, Criteria for the selection of CFB combustion or gasification based on available feedstocks and products required are discussed. Finally, a procedure for implementing Lurgi's CFB technology in developing countries is proposed. (author)

  14. Review: the development of neural stem cell biology and technology in regenerative medicine

    OpenAIRE

    Shanmuganathan, Divyanjali; Sivakumaran, Nivethika

    2018-01-01

    In the middle of the last century, it has been known that neural stem cells (NSCs) play a key role in regenerative medicine to cure the neurodegenerative disease. This review article covers about the introduction to neural stem cell biology and the isolation, differentiation and transplantation methods/techniques of neural stem cells. The neural stem cells can be transplanted into the human brain in the future to replace the damaged and dead neurons. The highly limited access to embryonic ste...

  15. Investigation of the available technologies and their feasibility for the conversion of food waste into fish feed in Hong Kong.

    Science.gov (United States)

    Cheng, Jack Y K; Lo, Irene M C

    2016-04-01

    Food waste is the largest constituent of municipal solid waste in Hong Kong, but food waste recycling is still in its infancy. With the imminent saturation of all landfill sites by 2020, multiple technologies are needed to boost up the food waste recycling rate in Hong Kong. Conversion of food waste into animal feeds is prevalent in Japan, South Korea, and Taiwan, treating over 40 % of their recycled food waste. This direction is worth exploring in Hong Kong once concerns over food safety are resolved. Fortunately, while feeding food waste to pigs and chickens poses threats to public health, feeding it to fish is considered low risk. In order to examine the feasibility of converting food waste into fish feed in Hong Kong, this paper investigates the market demand, technical viability, feed quality, regulatory hurdles, and potential contribution. The results show that a significant amount of food waste can be recycled by converting it into fish feed due to the enormous demand from feed factories in mainland China. Two conversion technologies, heat drying and black soldier fly bioconversion, are studied extensively. Black soldier fly bioconversion is preferable because the end-product, insect powder, is anticipated to gain import approval from mainland China. The authors suggest further research efforts to speed up its application for food waste recycling in urban cities.

  16. Conversion of Wastes into Bioelectricity and Chemicals by Using Microbial Electrochemical Technologies

    KAUST Repository

    Logan, B. E.; Rabaey, K.

    2012-01-01

    Waste biomass is a cheap and relatively abundant source of electrons for microbes capable of producing electrical current outside the cell. Rapidly developing microbial electrochemical technologies, such as microbial fuel cells, are part of a

  17. National Defense Education Program (NDEP) - Science, Technology, Engineering, and Mathematics (STEM) Education

    Science.gov (United States)

    2013-09-01

    inquiry and scientific pedagogy . 2.0 PROGRAM OBJECTIVES The DoD selected AFRL/XPPD, Domestic Partnering Branch, as the NDEP coordinator at...users access to LabTV, STEM career videos , STEM Education Quality Framework and Curriculum developed by the Dayton Regional STEM Center. In October

  18. Rethinking Teaching in STEM Education in a Community College: Role of Instructional Consultation and Digital Technologies

    Science.gov (United States)

    Kurland, Shelley Chih-Hsian

    Community college faculty members educate almost half of all U.S. undergraduates, who are often more diverse and more academically underprepared when compared to undergraduate students who attend four-year institutions. In addition, faculty members in community colleges are facing increased accountability for meeting student learning outcomes, expectations to adjust their teaching practices to include active learning practices, and expectations to incorporate more technologies into the classroom. Faculty developers are one of the support structures that faculty members can look to in order to meet those challenges. A survey of literature in faculty development suggests that instructional consultation can play an important role in shaping and transforming teaching practices. Hence, this action research study examined my work using instructional consulting with four full-time STEM faculty colleagues in order to examine and shape their teaching practices with and without the use of digital technologies. The two foci of the research, examining shifts in faculty participants' teaching practices, and my instructional consulting practices, were informed by Thomas and Brown's (2011) social view of learning and the concept of teaching and learning in a "co-learning" environment. Two dominant factors emerged regarding faculty participants' shift in teaching practices. These factors concerned: 1) the perception of control and 2) individual faculty participant's comfort level, expectations, and readiness. In addition to these two dominant factors, the instructional consultation process also supported a range of shifts in either mindset and/or teaching practices. My analysis showed that the use of digital technologies was not an essential factor in shifting faculty participant mindset and/or teaching practices, instead digital technologies were used to enhance the teaching process and students' learning experiences.

  19. Magneto-plasma separating technologies and their possible application for conversion spent fuel and radioactive waste

    International Nuclear Information System (INIS)

    Kovtun, Yu.V.; Skyibenko, Je.Yi.; Yuferov, V.B.

    2007-01-01

    A problem of spent fuel (SF) and radioactive waste (RAW) processing is considered in the views of using magneto-plasma technologies. Basing on this analysis, the block-diagram of RAW processing by the technology using a magneto-plasma separator is offered. The paper describes the device for material element separation, where the main physical mechanism of plasma formation and heating are collective processes involved by the plasma-beam interaction. The dimensions of a pilot-separating device are determined

  20. Alcoholysis: A Promising Technology for Conversion of Lignocellulose and Platform Chemicals.

    Science.gov (United States)

    Zhu, Shanhui; Guo, Jing; Wang, Xun; Wang, Jianguo; Fan, Weibin

    2017-06-22

    In the catalytic conversion of lignocellulose to valuable products, the first entry point is to break down these biopolymers to sugar units or aromatic monomers, which is conventionally achieved by hydrolysis in water medium. Recent years have seen tremendous progress in the alcoholysis process, which has remarkable advantages, such as the avoidance of treating waste water, suppression of humins or chars, and enhancement of reaction rate and product yield. Advances have been focused on the alcoholysis of cellulose, hemicellulose, and lignin to alkyl glucosides, xylosides, and aromatic monomers, respectively. Alcoholysis of the platform molecule furfuryl alcohol (FAL) to alkyl levulinate (AL) and integrated alcoholysis of cellulose and furfural into AL are also summarized. This Minireview highlights the comparisons between alcoholysis and hydrolysis, the reaction mechanism of alcoholysis, and future challenges for industrial applications. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. 1-,2-,3-e - Engaging All Exceptional Students in Science, Technology, Engineering and Mathematics (STEM)

    Science.gov (United States)

    Runyon, C. R.; Hall, C.; Baber, M.

    2013-12-01

    There are more than 50 million Americans with disabilities, approximately half of whom are students in a mainstreamed classroom. The National Association for Gifted Children estimates that approximately 3 million of those, 6% of the student population, are academically gifted, and 150,000 - 300,000 students of those are twice or triple exceptional (2e and 3e, respectively). The 2e and 3e refers to intellectually gifted children who also have some form(s) of disability. Unfortunately most schools in the US identify children by their giftedness or by their disability, but rarely by both. An apparent trend with 2e children, particularly when autism is paired with gifted, is that students identify with their disability instead of their strengths. 2e students have shown a propensity for interests in the science and technology fields. Few specialized programs and/or resources in STEM exist to engage and involve these exceptional students and fewer still is the number of faculty and staff trained to work with the twice and triple exceptionalities. Palmetto Scholars Academy (PSA), Charleston, SC a school for gifted and talented, provides a differentiated program to meet the educational needs of gifted learners, while also addressing the students' social/emotional needs. The Brown/MIT NASA Lunar Science Institute, in conjunction with the NASA South Carolina Space Grant Consortium, is working directly with educators from the PSA to identify what kinds of materials they need and what mediums work best for the different student (cap)abilities. This partnership will provide a means of 'consciousness raising' for teachers to help students develop their strengths and educators will gain a new understanding of 2e and 3e that will transfer into better instruction. One technique being implemented is the use of STEM-oriented engineering and technology design challenges and problem solving. These tasks allow students to use a variety of integrative and multi-disciplinary skills for

  2. Developing de novo human artificial chromosomes in embryonic stem cells using HSV-1 amplicon technology.

    Science.gov (United States)

    Moralli, Daniela; Monaco, Zoia L

    2015-02-01

    De novo artificial chromosomes expressing genes have been generated in human embryonic stem cells (hESc) and are maintained following differentiation into other cell types. Human artificial chromosomes (HAC) are small, functional, extrachromosomal elements, which behave as normal chromosomes in human cells. De novo HAC are generated following delivery of alpha satellite DNA into target cells. HAC are characterized by high levels of mitotic stability and are used as models to study centromere formation and chromosome organisation. They are successful and effective as gene expression vectors since they remain autonomous and can accommodate larger genes and regulatory regions for long-term expression studies in cells unlike other viral gene delivery vectors currently used. Transferring the essential DNA sequences for HAC formation intact across the cell membrane has been challenging for a number of years. A highly efficient delivery system based on HSV-1 amplicons has been used to target DNA directly to the ES cell nucleus and HAC stably generated in human embryonic stem cells (hESc) at high frequency. HAC were detected using an improved protocol for hESc chromosome harvesting, which consistently produced high-quality metaphase spreads that could routinely detect HAC in hESc. In tumour cells, the input DNA often integrated in the host chromosomes, but in the host ES genome, it remained intact. The hESc containing the HAC formed embryoid bodies, generated teratoma in mice, and differentiated into neuronal cells where the HAC were maintained. The HAC structure and chromatin composition was similar to the endogenous hESc chromosomes. This review will discuss the technological advances in HAC vector delivery using HSV-1 amplicons and the improvements in the identification of de novo HAC in hESc.

  3. China's science, technology, engineering, and mathematics (STEM) research environment: A snapshot.

    Science.gov (United States)

    Han, Xueying; Appelbaum, Richard P

    2018-01-01

    In keeping with China's President Xi Jinping's "Chinese Dream," China has set a goal of becoming a world-class innovator by 2050. China's higher education Science, Technology, Engineering, and Math (STEM) research environment will play a pivotal role in influencing whether China is successful in transitioning from a manufacturing-based economy to an innovation-driven, knowledge-based economy. Past studies on China's research environment have been primarily qualitative in nature or based on anecdotal evidence. In this study, we surveyed STEM faculty from China's top 25 universities to get a clearer understanding of how faculty members view China's overall research environment. We received 731 completed survey responses, 17% of which were from individuals who received terminal degrees from abroad and 83% of which were from individuals who received terminal degrees from domestic institutions of higher education. We present results on why returnees decided to study abroad, returnees' decisions to return to China, and differences in perceptions between returnees and domestic degree holders on the advantages of having a foreign degree. The top five challenges to China's research environment identified by survey respondents were: a promotion of short-term thinking and instant success (37% of all respondents); research funding (33%); too much bureaucratic or governmental intervention (31%); the evaluation system (27%); and a reliance on human relations (26%). Results indicated that while China has clearly made strides in its higher education system, there are numerous challenges that must be overcome before China can hope to effectively produce the kinds of innovative thinkers that are required if it is to achieve its ambitious goals. We also raise questions about the current direction of education and inquiry in China, particularly indications that government policy is turning inward, away from openness that is central to innovative thinking.

  4. Queer in STEM: Workplace Experiences Reported in a National Survey of LGBTQA Individuals in Science, Technology, Engineering, and Mathematics Careers.

    Science.gov (United States)

    Yoder, Jeremy B; Mattheis, Allison

    2016-01-01

    A survey of individuals working in science, technology, engineering, and mathematics (STEM) fields who identify as lesbian, gay, bisexual, trans*, queer, or asexual (LGTBQA) was administered online in 2013. Participants completed a 58-item questionnaire to report their professional areas of expertise, levels of education, geographic location, and gender and sexual identities and rated their work and social communities as welcoming or hostile to queer identities. An analysis of 1,427 responses to this survey provided the first broad portrait of this population, and it revealed trends related to workplace practices that can inform efforts to improve queer inclusivity in STEM workplaces.

  5. Conversion of wastes into bioelectricity and chemicals by using microbial electrochemical technologies.

    Science.gov (United States)

    Logan, Bruce E; Rabaey, Korneel

    2012-08-10

    Waste biomass is a cheap and relatively abundant source of electrons for microbes capable of producing electrical current outside the cell. Rapidly developing microbial electrochemical technologies, such as microbial fuel cells, are part of a diverse platform of future sustainable energy and chemical production technologies. We review the key advances that will enable the use of exoelectrogenic microorganisms to generate biofuels, hydrogen gas, methane, and other valuable inorganic and organic chemicals. Moreover, we examine the key challenges for implementing these systems and compare them to similar renewable energy technologies. Although commercial development is already underway in several different applications, ranging from wastewater treatment to industrial chemical production, further research is needed regarding efficiency, scalability, system lifetimes, and reliability.

  6. Circulating fluidized-bed technologies for the conversion of biomass into energy

    Energy Technology Data Exchange (ETDEWEB)

    Greil, C; Hirschfelder, H [Lurgi Energid und Umwelt GmbH, Frankfurt am Main (Germany)

    1995-12-01

    The paper introduces circulating fluidized-bed (CFB) combustion and CFB gasification. CFB combustion units are state-of-the-art and have proven their ability to convert biomass into power and/or steam. The existing units and projects in developing countries are discussed as examples of conventional technology. To illustrate advanced technologies, CFB gasification is discussed. Important process parameters of plants already in operation or under construction in developed countries are shown, Criteria for the selection of CFB combustion or gasification based on available feedstocks and products required are discussed. Finally, a procedure for implementing Lurgi`s CFB technology in developing countries is proposed. (author) 7 refs, 4 figs, 3 tabs

  7. Conversion of Wastes into Bioelectricity and Chemicals by Using Microbial Electrochemical Technologies

    KAUST Repository

    Logan, B. E.

    2012-08-09

    Waste biomass is a cheap and relatively abundant source of electrons for microbes capable of producing electrical current outside the cell. Rapidly developing microbial electrochemical technologies, such as microbial fuel cells, are part of a diverse platform of future sustainable energy and chemical production technologies. We review the key advances that will enable the use of exoelectrogenic microorganisms to generate biofuels, hydrogen gas, methane, and other valuable inorganic and organic chemicals. Moreover, we examine the key challenges for implementing these systems and compare them to similar renewable energy technologies. Although commercial development is already underway in several different applications, ranging from wastewater treatment to industrial chemical production, further research is needed regarding efficiency, scalability, system lifetimes, and reliability.

  8. Genome engineering through CRISPR/Cas9 technology in the human germline and pluripotent stem cells.

    Science.gov (United States)

    Vassena, R; Heindryckx, B; Peco, R; Pennings, G; Raya, A; Sermon, K; Veiga, A

    2016-06-01

    With the recent development of CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 genome editing technology, the possibility to genetically manipulate the human germline (gametes and embryos) has become a distinct technical possibility. Although many technical challenges still need to be overcome in order to achieve adequate efficiency and precision of the technology in human embryos, the path leading to genome editing has never been simpler, more affordable, and widespread. In this narrative review we seek to understand the possible impact of CRISR/Cas9 technology on human reproduction from the technical and ethical point of view, and suggest a course of action for the scientific community. This non-systematic review was carried out using Medline articles in English, as well as technical documents from the Human Fertilisation and Embryology Authority and reports in the media. The technical possibilities of the CRISPR/Cas9 technology with regard to human reproduction are analysed based on results obtained in model systems such as large animals and laboratory rodents. Further, the possibility of CRISPR/Cas9 use in the context of human reproduction, to modify embryos, germline cells, and pluripotent stem cells is reviewed based on the authors' expert opinion. Finally, the possible uses and consequences of CRISPR/cas9 gene editing in reproduction are analysed from the ethical point of view. We identify critical technical and ethical issues that should deter from employing CRISPR/Cas9 based technologies in human reproduction until they are clarified. Overcoming the numerous technical limitations currently associated with CRISPR/Cas9 mediated editing of the human germline will depend on intensive research that needs to be transparent and widely disseminated. Rather than a call to a generalized moratorium, or banning, of this type of research, efforts should be placed on establishing an open, international, collaborative and regulated research

  9. Changing the conversation: how ANS is telling a different story about nuclear science and technology

    International Nuclear Information System (INIS)

    Raap, B.

    2014-01-01

    'Full text': As nuclear scientists and engineers, our focus and expertise is in science and technology that yields benefits for society. Yet, we are also often in the position of explaining what can be very complex and technical issues to individuals who are not technical, and who perhaps are guided by misinformation about nuclear science and technology. Being effective communicators, and having an effective communications program at organizations like ANS,is critical if we are to maintain support for nuclear energy. Nuclear plants have shut down in the United States over the past year largely due to economic circumstances. The low price of natural gas and other factors make it extremely challenging for some nuclear plants to be competitive right now. Although this situation will eventually change, clear communications is critical.Fostering a good understanding of nuclear science and technology is needed now more than ever to help people gain an appreciation for the benefits that nuclear energy offers. Last year, ANS created a strategic communications plan. This communications plan called for improvements in all of our communication and outreach efforts. We have many work groups actively working on those improvements, which will be highlighted during the session. We also publicly launched the Center for Nuclear Science and Technology Information, a special communications initiative of ANS. The Center allows ANS to better leverage resources while building awareness about nuclear science and technology among a variety of audiences. Through the Center, ANS seeks to improve public understanding of nuclear science and technology, inform policy makers and their staff about nuclear fundamentals,engage journalists in telling a truthful story based on science, and inspire young people to explore nuclear science and technology. The Center allows ANS to produce improved public education tools that nuclear professionals and advocates can use when doing outreach. The

  10. Changing the conversation: how ANS is telling a different story about nuclear science and technology

    Energy Technology Data Exchange (ETDEWEB)

    Raap, B. [American Nuclear Society, La Grange Park, IL (United States)

    2014-07-01

    'Full text': As nuclear scientists and engineers, our focus and expertise is in science and technology that yields benefits for society. Yet, we are also often in the position of explaining what can be very complex and technical issues to individuals who are not technical, and who perhaps are guided by misinformation about nuclear science and technology. Being effective communicators, and having an effective communications program at organizations like ANS,is critical if we are to maintain support for nuclear energy. Nuclear plants have shut down in the United States over the past year largely due to economic circumstances. The low price of natural gas and other factors make it extremely challenging for some nuclear plants to be competitive right now. Although this situation will eventually change, clear communications is critical.Fostering a good understanding of nuclear science and technology is needed now more than ever to help people gain an appreciation for the benefits that nuclear energy offers. Last year, ANS created a strategic communications plan. This communications plan called for improvements in all of our communication and outreach efforts. We have many work groups actively working on those improvements, which will be highlighted during the session. We also publicly launched the Center for Nuclear Science and Technology Information, a special communications initiative of ANS. The Center allows ANS to better leverage resources while building awareness about nuclear science and technology among a variety of audiences. Through the Center, ANS seeks to improve public understanding of nuclear science and technology, inform policy makers and their staff about nuclear fundamentals,engage journalists in telling a truthful story based on science, and inspire young people to explore nuclear science and technology. The Center allows ANS to produce improved public education tools that nuclear professionals and advocates can use when doing outreach. The

  11. Capture, transformation and conversion of the solar energy by the technologies of concentration

    International Nuclear Information System (INIS)

    Ferriere, A.; Flamant, G.

    2003-01-01

    The specificities of the solar technologies at concentration are: high energy efficiency with increasing possibilities and the possibility of storage the solar energy by heat for a local and short dated utilization or by chemical storage (hydrogen for instance) for a delayed utilization or far from the capture area. This document takes stock on the concentration solar techniques, the electric power production by concentrated solar energy and the performance of concentrated solar plants, the industrial american experience of the SEGS plants, the hydrogen production by concentrated solar energy and discusses the scientific and technological locks. (A.L.B.)

  12. The Case for Using SMS Technologies to Support Distance Education Students in South Africa: Conversations

    Science.gov (United States)

    Viljoen, Jeanne-Marie; Du Preez, Carl; Cook, Antoinette

    2005-01-01

    The rate of adoption of mobile technologies in Africa's developing countries is amongst the highest in the world and by 2005 there may be almost 100 billion mobile users in Africa (Keegan, 2002; Brown, 2005). This is just one of the reasons why servicing distance students in this country through m-learning support tools should enjoy…

  13. Chapter 11: New Conversion Technologies for Liquid Biofuels Production in Africa

    NARCIS (Netherlands)

    Batidzirai, B.; Smeets, E.M.W.; Faaij, A.P.C.

    2012-01-01

    On the longer term, the production of second generation biofuels from lignocellulosic biomass is expected to become economically competitive with gasoline and diesel. A pre-requisite is that several technological hurdles will be overcome and that a large, stable supply of lignocellulosic biomass

  14. Science, Technology, Engineering, Math (STEM) in Higher Education from the Perspective of Female Students: An Institutional Ethnography

    Science.gov (United States)

    Parson, Laura J.

    A persistent disadvantage for females is systemically embedded in Science, Technology, Engineering, and Math (STEM) education in postsecondary institutions. As a result, undergraduate women majoring in STEM fields face a uniquely difficult path; yet, for the most part, recommendations made and supported in the literature have focused on recruitment of women to STEM fields or on ways to make women more successful and comfortable in their STEM major. These recommendations have so far proved to be insufficient to remedy a gender gap and serve to replicate the existing male hierarchy. In order to truly make the STEM classroom one in which women are welcome and comfortable and to challenge the existing social and scientific systems, it is necessary to explore and understand the social and political implications embedded within teaching and learning choices. This institutional ethnography addresses that gap. The purpose of this study was to uncover and describe the institutional practices of STEM education at a Midwest research university (MRU) from the standpoint of female undergraduate students. Using the framework of feminist standpoint theory, this study explored the everyday "work" of female undergraduate STEM students to provide a unique perspective on the STEM education teaching and learning environment. Data collection began with in-depth interviews with female undergraduate math and physics students. As the institutional processes shaping undergraduate participant experiences were identified, subsequent data collection included classroom observations, additional interviews with students and faculty, and analysis of the texts that mediate these processes (e.g., syllabi and student handbooks). Data analysis followed Carspecken's process of ethnographic data analysis that began with low-level coding, followed by high-level coding, and concluded by pulling codes together through the creation of themes. Analysis of data led to three key findings. First, undergraduate

  15. Technological advances in CO2 conversion electro-biorefinery: A step toward commercialization.

    Science.gov (United States)

    ElMekawy, Ahmed; Hegab, Hanaa M; Mohanakrishna, Gunda; Elbaz, Ashraf F; Bulut, Metin; Pant, Deepak

    2016-09-01

    The global atmospheric warming due to increased emissions of carbon dioxide (CO2) has attracted great attention in the last two decades. Although different CO2 capture and storage platforms have been proposed, the utilization of captured CO2 from industrial plants is progressively prevalent strategy due to concerns about the safety of terrestrial and aquatic CO2 storage. Two utilization forms were proposed, direct utilization of CO2 and conversion of CO2 to chemicals and energy products. The latter strategy includes the bioelectrochemical techniques in which electricity can be used as an energy source for the microbial catalytic production of fuels and other organic products from CO2. This approach is a potential technique in which CO2 emissions are not only reduced, but it also produce more value-added products. This review article highlights the different methodologies for the bioelectrochemical utilization of CO2, with distinctive focus on the potential opportunities for the commercialization of these techniques. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Taking Advantage of STEM (Science, Technology, Engineering, and Math) Popularity to Enhance Student/Public Engagement

    Science.gov (United States)

    Dittrich, T. M.

    2011-12-01

    For a student group on campus, "the public" can refer to other students on campus or citizens from the community (including children, parents, teenagers, professionals, tradespeople, older people, and others). All of these groups have something to offer that can enrich the experiences of a student group. Our group focuses on science, technology, engineering and math (STEM) education in K-12 schools, university courses, and outreach activities with the general public. We will discuss the experiences of "All Things STEM" on the University of Colorado-Boulder campus and outreach in Boulder and Weld County, CO. Our experiences include (1) tours and events that offer an opportunity for student/public interaction, (2) grant requests and projects that involve community outreach, and (3) organizing conferences and events with campus/public engagement. Since our group is STEM-oriented, tours of water treatment plants, recycling centers, and science museums are a great way to create connections. Our most successful campus/public tour is our annual tour of the Valmont Station coal power plant near Boulder. We solicit students from all over campus and Boulder public groups with the goal to form a diverse and intimate 8 person group (students, school teachers, mechanics, hotel managers, etc.) that takes a 1.5 hr tour of the plant guided by the Chief Engineer. This includes a 20 minute sit-down discussion of anything the group wants to talk about including energy policy, plant history, recent failures, coal versus other fuels, and environmental issues. The tour concludes with each member placing a welding shield over their face and looking at the flames in the middle of the boiler, a little excitement that adds to the connections the group forms with each other. We have received over 11,000 to work with local K-12 schools and CU-Boulder undergraduate and graduate classes to develop a platform to help students learn and explain water quality concepts in a more practical manner

  17. Preliminary Accident Analyses for Conversion of the Massachusetts Institute of Technology Reactor (MITR) from Highly Enriched to Low Enriched Uranium

    Energy Technology Data Exchange (ETDEWEB)

    Dunn, Floyd E. [Argonne National Lab. (ANL), Argonne, IL (United States); Olson, Arne P. [Argonne National Lab. (ANL), Argonne, IL (United States); Wilson, Erik H. [Argonne National Lab. (ANL), Argonne, IL (United States); Sun, Kaichao S. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Newton, Jr., Thomas H. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Hu, Lin-wen [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2013-09-30

    The Massachusetts Institute of Technology Reactor (MITR-II) is a research reactor in Cambridge, Massachusetts designed primarily for experiments using neutron beam and in-core irradiation facilities. It delivers a neutron flux comparable to current LWR power reactors in a compact 6 MW core using Highly Enriched Uranium (HEU) fuel. In the framework of its non-proliferation policies, the international community presently aims to minimize the amount of nuclear material available that could be used for nuclear weapons. In this geopolitical context most research and test reactors, both domestic and international, have started a program of conversion to the use of LEU fuel. A new type of LEU fuel based on an alloy of uranium and molybdenum (U-Mo) is expected to allow the conversion of U.S. domestic high performance reactors like MITR. This report presents the preliminary accident analyses for MITR cores fueled with LEU monolithic U-Mo alloy fuel with 10 wt% Mo. Preliminary results demonstrate adequate performance, including thermal margin to expected safety limits, for the LEU accident scenarios analyzed.

  18. Military conversion and its impacts on science and technology: Elements of the Italian case

    International Nuclear Information System (INIS)

    Farinelli, F.; Perani, G.

    1994-01-01

    Italy represents on of the success stories of post-war economic growth, gross national product has been higher in Italy than in most other industrialized countries. On the other hand the research and development growth initially did not result in successful performance in high technology products. This is due to existing of two innovation systems: a small firms network and core R and D system. These systems are quiet different in terms of capabilities, organization and performance. From the performed analysis of innovation system and military R and D activity it is suggested that the role of small/medium sized firms should be emphasized and that different public policies should be coordinated more efficiently. The industrial and technological policy should be matched together and investments on dual use technologies should be increased. A more selective procurement policy should lead to a wide process of restructuring military R and D and production system, the number of military firms should probably diminish and the remaining ones should have to increase their presence in competitive civilian markets

  19. Advanced gasifier and water gas shift technologies for low cost coal conversion to high hydrogen syngas

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, Andrew Kramer [Gas Technology Inst., Des Plaines, IL (United States)

    2016-09-30

    The Gas Technology Institute (GTI) and team members RTI International (RTI), Coanda Research and Development, and Nexant, are developing and maturing a portfolio of technologies to meet the United States Department of Energy (DOE) goals for lowering the cost of producing high hydrogen syngas from coal for use in carbon capture power and coal-to-liquids/chemicals. This project matured an advanced pilot-scale gasifier, with scalable and commercially traceable components, to readiness for use in a first-of-a-kind commercially-relevant demonstration plant on the scale of 500-1,000 tons per day (TPD). This was accomplished through cold flow simulation of the gasifier quench zone transition region at Coanda and through an extensive hotfire gasifier test program on highly reactive coal and high ash/high ash fusion temperature coals at GTI. RTI matured an advanced water gas shift process and catalyst to readiness for testing at pilot plant scale through catalyst development and testing, and development of a preliminary design basis for a pilot scale reactor demonstrating the catalyst. A techno-economic analysis was performed by Nexant to assess the potential benefits of the gasifier and catalyst technologies in the context of power production and methanol production. This analysis showed an 18%reduction in cost of power and a 19%reduction in cost of methanol relative to DOE reference baseline cases.

  20. Catalyst technology for biofuel production: Conversion of renewable lipids into biojet and biodiesel

    Directory of Open Access Journals (Sweden)

    Scharff Yves

    2013-09-01

    Full Text Available Renewable lipids based biofuels are an important tool to address issues raised by policies put in place in order to reduce the dependence of transportation sector on fossil fuels and to promote the development of non-food based, sustainable and eco-friendly fuels. This paper presents the main features of the heterogeneous catalysis technologies Axens has developed for the production of biofuels from renewable lipids: the first by transesterification to produce fatty acid methyl esters or biodiesel and the second by hydrotreating to produce isoparaffinic hydroprocessed ester and fatty acids, high blending rate drop-in diesel and jet biofuels.

  1. Environmental assessment of gasification technology for biomass conversion to energy in comparison with other alternatives

    DEFF Research Database (Denmark)

    Nguyen, T Lan T; Hermansen, John Erik; Nielsen, Rasmus Glar

    2013-01-01

    that the combustion of biomass and fossil fuel references for electricity production takes place in a combined heat and power plant, but as a sensitivity analysis, we also consider combustion in a condensing mode power plant where only electricity is produced. Our results show that the production of 1 k...... on gasification technology appears to be more environmentally friendly than straw direct combustion in all impact categories considered. The comparison with coal results in the same conclusion as that reached in the comparison with straw direct combustion. The comparison with natural gas shows that using straw...... about whether or not heat recovery is considered....

  2. Future mission opportunities and requirements for advanced space photovoltaic energy conversion technology

    Science.gov (United States)

    Flood, Dennis J.

    1990-01-01

    The variety of potential future missions under consideration by NASA will impose a broad range of requirements on space solar arrays, and mandates the development of new solar cells which can offer a wide range of capabilities to mission planners. Major advances in performance have recently been achieved at several laboratories in a variety of solar cell types. Many of those recent advances are reviewed, the areas are examined where possible improvements are yet to be made, and the requirements are discussed that must be met by advanced solar cell if they are to be used in space. The solar cells of interest include single and multiple junction cells which are fabricated from single crystal, polycrystalline and amorphous materials. Single crystal cells on foreign substrates, thin film single crystal cells on superstrates, and multiple junction cells which are either mechanically stacked, monolithically grown, or hybrid structures incorporating both techniques are discussed. Advanced concentrator array technology for space applications is described, and the status of thin film, flexible solar array blanket technology is reported.

  3. Fiscal 1994 achievement report. International Clean Energy Network Using Hydrogen Conversion (WE-NET) technology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    Research and development was made for the WE-NET (World Energy Network) project which aims to carry out hydrogen production, transportation, and supply to consumers, by the use of renewable energy. In this fiscal year, surveys were conducted of the status of research and development in each of the fields, and research was started on element technologies in some of the fields. Under subtask 1, surveys and studies were started for pilot plant phase 2. Under subtask 2, an international symposium was held for the enhancement of technical information exchange. Under subtask 3, a liquid hydrogen system conceptual design was prepared for the estimation of facility cost, etc. Under subtask 4, small experimental cells were fabricated for evaluating electrode bonding methods. Under subtask 5, studies were made about the processes of the helium Brayton cycle and hydrogen Claude cycle for the development of a large-scale hydrogen liquefaction plant. Under subtasks 6-9, furthermore, surveys and studies were conducted about low-temperature substance technology, hydrogen energy, hydrogen combustion turbines, and so forth. (NEDO)

  4. Development of High Yield Feedstocks and Biomass Conversion Technology for Renewable Energy

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Andrew G. [Univ. of Hawaii, Honolulu, HI (United States); Crow, Susan [Univ. of Hawaii, Honolulu, HI (United States); DeBeryshe, Barbara [Univ. of Hawaii, Honolulu, HI (United States); Ha, Richard [Hamakua Springs County Farms, Hilo, HI (United States); Jakeway, Lee [Hawaiian Commercial and Sugar Company, Puunene, HI (United States); Khanal, Samir [Univ. of Hawaii, Honolulu, HI (United States); Nakahata, Mae [Hawaiian Commercial and Sugar Company, Puunene, HI (United States); Ogoshi, Richard [Univ. of Hawaii, Honolulu, HI (United States); Shimizu, Erik [Univ. of Hawaii, Honolulu, HI (United States); Stern, Ivette [Univ. of Hawaii, Honolulu, HI (United States); Turano, Brian [Univ. of Hawaii, Honolulu, HI (United States); Turn, Scott [Univ. of Hawaii, Honolulu, HI (United States); Yanagida, John [Univ. of Hawaii, Honolulu, HI (United States)

    2015-04-09

    This project had two main goals. The first goal was to evaluate several high yielding tropical perennial grasses as feedstock for biofuel production, and to characterize the feedstock for compatible biofuel production systems. The second goal was to assess the integration of renewable energy systems for Hawaii. The project focused on high-yield grasses (napiergrass, energycane, sweet sorghum, and sugarcane). Field plots were established to evaluate the effects of elevation (30, 300 and 900 meters above sea level) and irrigation (50%, 75% and 100% of sugarcane plantation practice) on energy crop yields and input. The test plots were extensive monitored including: hydrologic studies to measure crop water use and losses through seepage and evapotranspiration; changes in soil carbon stock; greenhouse gas flux (CO2, CH4, and N2O) from the soil surface; and root morphology, biomass, and turnover. Results showed significant effects of environment on crop yields. In general, crop yields decrease as the elevation increased, being more pronounced for sweet sorghum and energycane than napiergrass. Also energy crop yields were higher with increased irrigation levels, being most pronounced with energycane and less so with sweet sorghum. Daylight length greatly affected sweet sorghum growth and yields. One of the energy crops (napiergrass) was harvested at different ages (2, 4, 6, and 8 months) to assess the changes in feedstock characteristics with age and potential to generate co-products. Although there was greater potential for co-products from younger feedstock, the increased production was not sufficient to offset the additional cost of harvesting multiple times per year. The feedstocks were also characterized to assess their compatibility with biochemical and thermochemical conversion processes. The project objectives are being continued through additional support from the Office of Naval Research, and the Biomass Research and Development

  5. Vehicle test report: South Coast technology electric conversion of a Volkswagen Rabbit

    Science.gov (United States)

    Price, T. W.; Shain, T. W.; Bryant, J. A.

    1981-01-01

    The South Coast Technology Volkswagen Rabbit, was tested at the Jet Propulsion Laboratory's (JPL) dynamometer facility and at JPL's Edwards Test Station (ETS). The tests were performed to characterize certain parameters of the South Coast Rabbit and to provide baseline data that will be used for the comparison of near term batteries that are to be incorporated into the vehicle. The vehicle tests were concentrated on the electrical drive system; i.e., the batteries, controller, and motor. The tests included coastdowns to characterize the road load, maximum effort acceleration, and range evaluation for both cyclic and constant speed conditions. A qualitative evaluation of the vehicle was made by comparing its constant speed range performance with those vehicles described in the document 'state of the Art assessment of Electric and Hybrid Vehicles'. The Rabbit performance was near to the best of the 1977 vehicles.

  6. A new oxalate co-conversion technology based on liquid/liquid extraction columns

    International Nuclear Information System (INIS)

    Borda, Gilles; Ode, Denis; Duhamet, Jean; Allegri, Patrick

    2008-01-01

    The current objective of fabricating non proliferating nuclear fuel by 'direct' coprecipitation of uranium, plutonium and minor actinides requires a new process to replace the (co)precipitation step. The technological impact of an increased capacity on the work zone could require the development of a different concept for a continuous device capable of ensuring the proposed goal. A new type of device designed and patented by the Cea was tested in 2007. The patent is for organic confinement in a pulsed column. First, precipitation of cerium or neodymium alone has been carried out in this device, with satisfactory results. Moreover, a recent test campaign demonstrated that a uranium-cerium co-precipitate easily forms when the two nitrates are mixed in a pulsed column of the same size operating under very similar process conditions. Qualitatively, the co-precipitate meets the process requirements. (authors)

  7. A new oxalate co-conversion technology based on liquid/liquid extraction columns

    Energy Technology Data Exchange (ETDEWEB)

    Borda, Gilles; Ode, Denis; Duhamet, Jean; Allegri, Patrick [CEA Nuclear Energy Division - Fuel Cycle Technology Division - System and Chemical Engineering Device Marcoule - 30207 Bagnols sur Ceze (France)

    2008-07-01

    The current objective of fabricating non proliferating nuclear fuel by 'direct' coprecipitation of uranium, plutonium and minor actinides requires a new process to replace the (co)precipitation step. The technological impact of an increased capacity on the work zone could require the development of a different concept for a continuous device capable of ensuring the proposed goal. A new type of device designed and patented by the Cea was tested in 2007. The patent is for organic confinement in a pulsed column. First, precipitation of cerium or neodymium alone has been carried out in this device, with satisfactory results. Moreover, a recent test campaign demonstrated that a uranium-cerium co-precipitate easily forms when the two nitrates are mixed in a pulsed column of the same size operating under very similar process conditions. Qualitatively, the co-precipitate meets the process requirements. (authors)

  8. Fiscal 1996 achievement report. International Clean Energy Network Using Hydrogen Conversion (WE-NET) technology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Research and development was performed for the WE-NET (World Energy Network) project which aims to carry out hydrogen production, transportation, and supply to consumers, by the use of renewable energy. Under subtask 1, the whole WE-NET project was subjected to evaluation, which included coordination between the respective tasks. Under subtask 2, information exchange and research cooperation were carried out with research institutes overseas. Under subtask 3, a conceptual design was prepared of a total system using ammonia as the medium for hydrogen transportation, accident data were collected and screened, and safety measures and evaluation techniques were developed and improved. Under subtask 4, the hot press method and the electroless plating method were selected as better electrode bonding methods. Under subtask 5, hydrogen liquefaction cycle processes, liquid hydrogen tankers, storage facilities, etc., were studied. Under subtasks 6-9, furthermore, investigations were conducted about low-temperature substance technology, hydrogen energy, hydrogen combustion turbine, etc. (NEDO)

  9. Solar cell array design handbook - The principles and technology of photovoltaic energy conversion

    Science.gov (United States)

    Rauschenbach, H. S.

    1980-01-01

    Photovoltaic solar cell array design and technology for ground-based and space applications are discussed from the user's point of view. Solar array systems are described, with attention given to array concepts, historical development, applications and performance, and the analysis of array characteristics, circuits, components, performance and reliability is examined. Aspects of solar cell array design considered include the design process, photovoltaic system and detailed array design, and the design of array thermal, radiation shielding and electromagnetic components. Attention is then given to the characteristics and design of the separate components of solar arrays, including the solar cells, optical elements and mechanical elements, and the fabrication, testing, environmental conditions and effects and material properties of arrays and their components are discussed.

  10. A new co conversion technology based on liquid/liquid extraction column

    Energy Technology Data Exchange (ETDEWEB)

    Borda, Gilles; Ode, Denis; Duhamet, Jean; Brackx, Emmanuelle [CEA Valrho - Marcoule - BP 17171 - 30207 Bagnols sur Ceze Cedex (France)

    2009-06-15

    The current objective of implementing 'direct' coprecipitation of uranium, plutonium and minor actinides for nuclear fuel re-fabrication leads to reconsider the (co)precipitation step, and more precisely its adaptability to new flowrates' specifications. Indeed, coprecipitation of a uranium fraction together with plutonium results in an appreciable increase in the process flow rates for this step. The technological impact of the increase in capacity could require the development of a different concept for a continuous device capable of ensuring the proposed process. A new type of device designed and patented by the CEA has been tested since 2007. The patent is for organic confinement in a pulsed column (PC) or Couette column (CC). The precipitation reaction between the oxalate complexing agent and a surrogate nitrate-cerium(II) or neodymium(III) alone, or coprecipitated uranium(IV) and cerium(III), occurs within an emulsion created in the device by these two phases flowing with a counter-current chemically inert organic phase (for example TPH) produced by the stirring action of the pulsator (PC) or the central rotor (CC). The precipitate is confined and thus does not form deposits on the vessel walls (which are also water-repellent); it flows downward by gravity and exits the column continuously into a settling tank. This paper describes the recent results obtained with this new technology for precipitation of Ce and Nd and coprecipitation of U + Ce in pulsed column and Couette column. It describes a first modeling allowing further extrapolation of this device to high capacities. (authors)

  11. Underrepresented Racial/Ethnic Minority Graduate Students in Science, Technology, Engineering, and Math (STEM) Disciplines: A Cross Institutional Analysis of their Experiences

    Science.gov (United States)

    Figueroa, Tanya

    Considering the importance of a diverse science, technology, engineering, and math (STEM) research workforce for our country's future, it is troubling that many underrepresented racial minority (URM) students start graduate STEM programs, but do not finish. However, some institutional contexts better position students for degree completion than others. The purpose of this study was to uncover the academic and social experiences, power dynamics, and programmatic/institutional structures URM students face within their graduate STEM programs that hinder or support degree progression. Using a critical socialization framework applied in a cross-comparative qualitative study, I focused on how issues of race, ethnicity, and underrepresentation within the educational contexts shape students' experiences. Data was collected from focus group interviews involving 53 URM graduate students pursuing STEM disciplines across three institution types -- a Predominately White Institution, a Hispanic-Serving Institution, and a Historically Black University. Results demonstrate that when students' relationships with faculty advisors were characterized by benign neglect, students felt lost, wasted time and energy making avoidable mistakes, had less positive views of their experiences, and had more difficulty progressing through classes or research, which could cause them to delay time to degree completion or to leave with a master's degree. Conversely, faculty empowered students when they helped them navigate difficult processes/milestones with regular check-ins, but also allowed students room to make decisions and solve problems independently. Further, faculty set the tone for the overall interactional culture and helping behavior in the classroom and lab contexts; where faculty modeled collaboration and concern for students, peers were likely to do the same. International peers sometimes excluded domestic students both socially and academically, which had a negative affect on

  12. Motivating Children to Develop Their Science, Technology, Engineering, and Mathematics (STEM) Talent

    Science.gov (United States)

    Andersen, Lori

    2013-01-01

    Motivation in mathematics and science appears to be more important to STEM occupational choice than ability. Using the expectancy value model, parents may be able to recognize potential barriers to children's selection of a STEM occupation and take actions to help facilitate talent development. These are especially important for parents of…

  13. Can Financial Aid Help to Address the Growing Need for STEM Education? The Effects of Need-Based Grants on the Completion of Science, Technology, Engineering, and Math Courses and Degrees

    Science.gov (United States)

    Castleman, Benjamin L.; Long, Bridget Terry; Mabel, Zachary

    2018-01-01

    Although workers in science, technology, engineering, and math (STEM) fields earn above-average wages, the number of college graduates prepared for STEM jobs lags behind employer demand. A key question is how to recruit and retain college students in STEM majors. We offer new evidence on the role of financial aid in supporting STEM attainment.…

  14. ORC technology for waste-wood to energy conversion in the furniture manufacturing industry

    Directory of Open Access Journals (Sweden)

    Moro Riccardo

    2008-01-01

    Full Text Available Exploitation of low and medium temperature thermal sources, in particular those based on biomass combustion and on industrial residual heat recovery, has been increasingly investigated in the last decades, accordingly to the growing interest towards reduction in primary energy consumption and environmental issues. Organic Rankine cycle technology allows designing power plants that are less demanding in terms of auxiliaries, safety systems, maintenance and operating costs when compared to conventional water steam power plants. To support the preliminary technical and economic design of this kind of plants in different contexts, a simulation code of part load and off-design operation of an organic Rankine cycle unit for combined heat and power has been developed. In the paper, taking the real situation of a furniture manufacturing factory as a starting point, it is shown how all energy flows occurring all year long inside the combined heat and power plant, can be estimated on the basis of the thermal user duty time profile, the available biomass flow rate and the adopted operation strategy. This information is the basis in order to correctly evaluate the energetic, economic and environmental advantages of the proposed technical solution, with respect to a particular context, as it is shown in the concluding part of the paper.

  15. Technologies enabling autologous neural stem cell-based therapies for neurodegenerative disease and injury

    Science.gov (United States)

    Bakhru, Sasha H.

    The intrinsic abilities of mammalian neural stem cells (NSCs) to self-renew, migrate over large distances, and give rise to all primary neural cell types of the brain offer unprecedented opportunity for cell-based treatment of neurodegenerative diseases and injuries. This thesis discusses development of technologies in support of autologous NSC-based therapies, encompassing harvest of brain tissue biopsies from living human patients; isolation of NSCs from harvested tissue; efficient culture and expansion of NSCs in 3D polymeric microcapsule culture systems; optimization of microcapsules as carriers for efficient in vivo delivery of NSCs; genetic engineering of NSCs for drug-induced, enzymatic release of transplanted NSCs from microcapsules; genetic engineering for drug-induced differentiation of NSCs into specific therapeutic cell types; and synthesis of chitosan/iron-oxide nanoparticles for labeling of NSCs and in vivo tracking by cellular MRI. Sub-millimeter scale tissue samples were harvested endoscopically from subventricular zone regions of living patient brains, secondary to neurosurgical procedures including endoscopic third ventriculostomy and ventriculoperitoneal shunt placement. On average, 12,000 +/- 3,000 NSCs were isolated per mm 3 of subventricular zone tissue, successfully demonstrated in 26 of 28 patients, ranging in age from one month to 68 years. In order to achieve efficient expansion of isolated NSCs to clinically relevant numbers (e.g. hundreds of thousands of cells in Parkinson's disease and tens of millions of cells in multiple sclerosis), an extracellular matrix-inspired, microcapsule-based culture platform was developed. Initial culture experiments with murine NSCs yielded unprecedented expansion folds of 30x in 5 days, from initially minute NSC populations (154 +/- 15 NSCs per 450 mum diameter capsule). Within 7 days, NSCs expanded as almost perfectly homogenous populations, with 94.9% +/- 4.1% of cultured cells staining positive for

  16. A Decade of Building a STEM Educational Community of Practice from the Ground Up: Leveraging Technology, Visualization, and Evaluation

    Science.gov (United States)

    Pisut, D.; MacIntosh, E.; McDougall, C.; Peddicord, H.; Russell, E. L.; Zepecki, S., III

    2017-12-01

    A small group of scientists and museum directors sit in a room and ponder, "What do we do with this thing?" It was ten years ago, and the Science On a Sphere was a nascent educational technology. Since that time, NOAA has built a energetic community of practice, with over 150 institutional network members ranging from museums and aquariums, to scientific laboratories, and even documentary producers. A key to the long term success of this educational community has been its constant evolution - driven by needs assessments of the network partners, NOAA's foresight on how to improve user experiences by integrating new visualizations, storytelling, and improved technology, and the ability of institutions to integrate the technologies into their other STEM offerings. In this talk we'll cover specific examples of the challenges that have arisen, and how NOAA, and its close partner NASA, has evolved the program offerings and technologies to meet the needs of this educational community of practice, along with some thoughts on the future of the Science On a Sphere Collaborative Network and NOAA's STEM educational technology portfolio.

  17. Student and high-school characteristics related to completing a science, technology, engineering or mathematics (STEM) major in college

    Science.gov (United States)

    LeBeau, Brandon; Harwell, Michael; Monson, Debra; Dupuis, Danielle; Medhanie, Amanuel; Post, Thomas R.

    2012-04-01

    Background: The importance of increasing the number of US college students completing degrees in science, technology, engineering or mathematics (STEM) has prompted calls for research to provide a better understanding of factors related to student participation in these majors, including the impact of a student's high-school mathematics curriculum. Purpose: This study examines the relationship between various student and high-school characteristics and completion of a STEM major in college. Of specific interest is the influence of a student's high-school mathematics curriculum on the completion of a STEM major in college. Sample: The sample consisted of approximately 3500 students from 229 high schools. Students were predominantly Caucasian (80%), with slightly more males than females (52% vs 48%). Design and method: A quasi-experimental design with archival data was used for students who enrolled in, and graduated from, a post-secondary institution in the upper Midwest. To be included in the sample, students needed to have completed at least three years of high-school mathematics. A generalized linear mixed model was used with students nested within high schools. The data were cross-sectional. Results: High-school predictors were not found to have a significant impact on the completion of a STEM major. Significant student-level predictors included ACT mathematics score, gender and high-school mathematics GPA. Conclusions: The results provide evidence that on average students are equally prepared for the rigorous mathematics coursework regardless of the high-school mathematics curriculum they completed.

  18. Exploiting pluripotent stem cell technology for drug discovery, screening, safety, and toxicology assessments.

    Science.gov (United States)

    McGivern, Jered V; Ebert, Allison D

    2014-04-01

    In order for the pharmaceutical industry to maintain a constant flow of novel drugs and therapeutics into the clinic, compounds must be thoroughly validated for safety and efficacy in multiple biological and biochemical systems. Pluripotent stem cells, because of their ability to develop into any cell type in the body and recapitulate human disease, may be an important cellular system to add to the drug development repertoire. This review will discuss some of the benefits of using pluripotent stem cells for drug discovery and safety studies as well as some of the recent applications of stem cells in drug screening studies. We will also address some of the hurdles that need to be overcome in order to make stem cell-based approaches an efficient and effective tool in the quest to produce clinically successful drug compounds. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Can mammalian cloning combined with embryonic stem cell technologies be used to treat human diseases?

    Science.gov (United States)

    Hadjantonakis, Anna-Katerina; Papaioannou, Virginia E

    2002-01-01

    Cloning is commonly perceived as a means of generating genetically identical individuals, but it can also be used to obtain genetically matched embryo-derived stem cells, which could potentially be used in the treatment of patients. A recent report offers the first 'proof of principle' of such cloning for therapeutic purposes, referred to as nuclear transplantation to produce stem cells for autologous transplantation. PMID:12186652

  20. Conversion of Low Quality Waste Heat to Electric Power with Small-Scale Organic Rankine Cycle (ORC) Engine/Generator Technology

    Science.gov (United States)

    2016-08-01

    efficiency by reducing energy consumption associated with electrical generation and reduces greenhouse gas emissions by increasing electrical generating...integrated system fuel economy test conditions This computation requires prediction of fuel consumption over baseline and integrated system load...EW-201251) Conversion of Low Quality Waste Heat to Electric Power with Small-Scale Organic Rankine Cycle (ORC) Engine/Generator Technology

  1. Adipose-derived adult stem cells: available technologies for potential clinical regenerative applications in dentistry.

    Science.gov (United States)

    Catalano, Enrico; Cochis, Andrea; Varoni, Elena; Rimondini, Lia; Carrassi, Antonio; Azzimonti, Barbara

    2013-01-01

    Tissue homeostasis depends closely on the activity and welfare of adult stem cells. These cells represent a promising tool for biomedical research since they can aid in treatment and promote the regeneration of damaged organs in many human disorders. Adult stem cells indefinitely preserve their ability to self-renew and differentiate into various phenotypes; this capacity could be promoted in vitro by particular culture conditions (differentiation media) or spontaneously induced in vivo by exploiting the biochemical and mechanical properties of the tissue in which the stem cells are implanted. Among the different sources of adult stem cells, adipose tissue is an attractive possibility thanks to its ready availability and the standard extraction techniques at our disposal today. This review discusses the isolation, characterization, and differentiation of human adipose-derived adult stem cells, as well as regeneration strategies, therapeutic uses, and adverse effects of their delivery. In particular, since oral disorders (e.g., trauma, erosion, and chronic periodontitis) often cause the loss of dental tissue along with functional, phonetic, and aesthetic impairment, this review focuses on the application of human adipose-derived adult stem cells, alone or in combination with biomaterials, in treating oral diseases.

  2. CO2 injection into submarine, CH4-hydrate bearing sediments: Parameter studies towards the development of a hydrate conversion technology

    Science.gov (United States)

    Deusner, Christian; Bigalke, Nikolaus; Kossel, Elke; Haeckel, Matthias

    2013-04-01

    the reservoir is minimized. Our results clearly indicate that the formation of mixed CH4-CO2-hydrates is an important aspect in the conversion process. The experimental studies have shown that the injection of heated CO2 into the hydrate reservoir induces a variety of spatial and temporal processes which result in substantial bulk heterogeneity. Current numerical simulators are not able to predict these process dynamics and it is important to improve available transport-reaction models (e.g. to include the effect of bulk sediment permeability on the conversion dynamics). Our results confirm that experimental studies are important to better understand the mechanisms of hydrate dissociation and conversion at CO2-injection conditions as a basis towards the development of a suitable hydrate conversion technology. The application of non-invasive analytical methods such as Magnetic Resonance Imaging (MRI) and Raman microscopy are important tools, which were applied to resolve process dynamics on the pore scale. Additionally, the NESSI system is being modified to allow high-pressure flow-through experiments under triaxial loading to better simulate hydrate-sediment mechanics. This aspect is important for overall process development and evaluation of process safety issues.

  3. An Overview of Natural Gas Conversion Technologies for Co-Production of Hydrogen and Value-Added Solid Carbon Products

    Energy Technology Data Exchange (ETDEWEB)

    Dagle, Robert A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Dagle, Vanessa [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bearden, Mark D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Holladay, Jamelyn D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Krause, Theodore R. [Argonne National Lab. (ANL), Argonne, IL (United States); Ahmed, Shabbir [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-11-16

    This report was prepared in response to the U.S. Department of Energy Fuel Cell Technologies Office Congressional Appropriation language to support research on carbon-free production of hydrogen using new chemical processes that utilize natural gas to produce solid carbon and hydrogen. The U.S. produces 9-10 million tons of hydrogen annually with more than 95% of the hydrogen produced by steam-methane reforming (SMR) of natural gas. SMR is attractive because of its high hydrogen yield; but it also converts the carbon to carbon dioxide. Non-oxidative thermal decomposition of methane to carbon and hydrogen is an alternative to SMR and produces CO2-free hydrogen. The produced carbon can be sold as a co-product, thus providing economic credit that reduces the delivered net cost of hydrogen. The combination of producing hydrogen with potentially valuable carbon byproducts has market value in that this allows greater flexibility to match the market prices of hydrogen and carbon. That is, the higher value product can subsidize the other in pricing decisions. In this report we highlight the relevant technologies reported in the literature—primarily thermochemical and plasma conversion processes—and recent research progress and commercial activities. Longstanding technical challenges include the high energetic requirements (e.g., high temperatures and/or electricity requirements) necessary for methane activation and, for some catalytic processes, the separation of solid carbon product from the spent catalyst. We assess current and new carbon product markets that could be served given technological advances, and we discuss technical barriers and potential areas of research to address these needs. We provide preliminary economic analysis for these processes and compare to other emerging (e.g., electrolysis) and conventional (e.g., SMR) processes for hydrogen production. The overarching conclusion of this study is that the cost of hydrogen can be potentially

  4. Tracking the conversion of nitrogen during pyrolysis of antibiotic mycelial fermentation residues using XPS and TG-FTIR-MS technology.

    Science.gov (United States)

    Zhu, Xiangdong; Yang, Shijun; Wang, Liang; Liu, Yuchen; Qian, Feng; Yao, Wenqing; Zhang, Shicheng; Chen, Jianmin

    2016-04-01

    Antibiotic mycelial fermentation residues (AMFRs), which are emerging solid pollutants, have been recognized as hazardous waste in China since 2008. Nitrogen (N), which is an environmental sensitivity element, is largely retained in AMFR samples derived from fermentation substrates. Pyrolysis is a promising technology for the treatment of solid waste. However, the outcomes of N element during the pyrolysis of AMFRs are still unknown. In this study, the conversion of N element during the pyrolysis of AMFRs was tracked using XPS (X-ray photoelectron spectroscopy) and online TG-FTIR-MS (Thermogravimetry-Fourier transform infrared-Mass spectrometry) technology. In the AMFR sample, organic amine-N, pyrrolic-N, protein-N, pyridinic-N, was the main N-containing species. XPS results indicated that pyrrolic-N and pyridinic-N were retained in the AMFR-derived pyrolysis char. More stable species, such as N-oxide and quaternary-N, were also produced in the char. TG-FTIR-MS results indicated that NH3 and HCN were the main gaseous species, and their contents were closely related to the contents of amine-N and protein-N, and pyrrolic-N and pyridinic-N of AMFRs, respectively. Increases in heating rate enhanced the amounts of NH3 and HCN, but had less of an effect on the degradation degree of AMFRs. N-containing organic compounds, including amine-N, nitrile-N and heterocyclic-N, were discerned from the AMFR pyrolysis process. Their release range was extended with increasing of heating rate and carbon content of AMFR sample. This work will help to take appropriate measure to reduce secondary pollution from the treatment of AMFRs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Towards the realization of a basic professional prole model forScience, Technology and Mathematics (STEM teachers

    Directory of Open Access Journals (Sweden)

    Juan Quílez

    2017-01-01

    Full Text Available In  this  work  it  is  both  discussed  and  provided  a  framework  of  specific  competences  that  may  serve  as a  guide  for  setting  up  an  ongoing  process  in  the  professional  development  of  Science,  Technology  and Mathematics  (STEM  teachers.  The  fundamentals  of  the  TPACK  model  serve  to  base  the  theoretical background of this scheme, to which we have incorporated an additional feature which means to consider the linguistic (L dimension, thus transforming it into the TPACLK model. The different detailed professional STEM capacities have been classified into six main sections. The two first points discussed establish the STEM disciplinary and didactic capacities; the third section corresponds to the role of language in the STEM classroom; the fourth category is focused on the motivational elements of the teaching and learning process;  the   fifth  corresponds  to  the  self-perception  of  teachers  and  the  last  section  summarises  how  to integrate effectively the information and communication technologies into the educational STEM activity. This professional development is framed within innovative and research educational activities.

  6. Generation of human hepatocytes by stem cell technology: definition of the hepatocyte.

    Science.gov (United States)

    Hengstler, Jan G; Brulport, Marc; Schormann, Wiebke; Bauer, Alexander; Hermes, Matthias; Nussler, Andreas K; Fandrich, Fred; Ruhnke, Maren; Ungefroren, Hendrik; Griffin, Louise; Bockamp, Ernesto; Oesch, Franz; von Mach, Marc-Alexander

    2005-06-01

    Since 1999, numerous articles have reported the generation of hepatocytes from different types of extrahepatic stem or precursor cells. This opens exciting new possibilities for pharmacology and toxicology, as well as for cell therapy. Hepatocyte marker expression, including albumin, cytokeratin 18, c-met, alpha-fetoprotein and cytochrome P450 3A4 and -2B6, has been observed after transplantation of different types of human stem cells into the liver of laboratory animals or in vitro after incubation with cytokines. These intriguing observations have prompted scientists to classify stem cell-derived cell populations as hepatocytes. However, this conclusion may be premature. It has been shown that factors of the liver microenvironment can induce expression of a limited number of hepatocyte marker genes in nonhepatic cell types. To conclude on the grounds of a limited number of markers that these cells are true hepatocytes is not indicated. In this case one should carefully evaluate crucial hepatocyte-defining enzymatic properties. The present article: i) reviews studies describing the fate of extrahepatic human stem and precursor cells in livers of laboratory animals, including the possibility of cell fusion; and ii) critically discusses the phenotype of stem cells after application of various differentiation protocols aimed at generating human hepatocytes. In addition, the necessary criteria needed for defining a true hepatocyte are suggested. Establishing the necessary properties for stem cell-derived hepatocytes is timely and reasonable, and thus avoids further misleading semantic confusion. Finally, it is essential to understand that the definition of a bona fide hepatocyte should not be limited to qualitative assays, such as reverse transcriptase polymerase chain reaction and immunohistochemistry, but has to include a quantitative analysis of enzymatic activities, which allows direct comparison with primary hepatocytes. Although the stem cell

  7. Systematic review of induced pluripotent stem cell technology as a potential clinical therapy for spinal cord injury.

    Science.gov (United States)

    Kramer, Anne S; Harvey, Alan R; Plant, Giles W; Hodgetts, Stuart I

    2013-01-01

    Transplantation therapies aimed at repairing neurodegenerative and neuropathological conditions of the central nervous system (CNS) have utilized and tested a variety of cell candidates, each with its own unique set of advantages and disadvantages. The use and popularity of each cell type is guided by a number of factors including the nature of the experimental model, neuroprotection capacity, the ability to promote plasticity and guided axonal growth, and the cells' myelination capability. The promise of stem cells, with their reported ability to give rise to neuronal lineages to replace lost endogenous cells and myelin, integrate into host tissue, restore functional connectivity, and provide trophic support to enhance and direct intrinsic regenerative ability, has been seen as a most encouraging step forward. The advent of the induced pluripotent stem cell (iPSC), which represents the ability to "reprogram" somatic cells into a pluripotent state, hails the arrival of a new cell transplantation candidate for potential clinical application in therapies designed to promote repair and/or regeneration of the CNS. Since the initial development of iPSC technology, these cells have been extensively characterized in vitro and in a number of pathological conditions and were originally reported to be equivalent to embryonic stem cells (ESCs). This review highlights emerging evidence that suggests iPSCs are not necessarily indistinguishable from ESCs and may occupy a different "state" of pluripotency with differences in gene expression, methylation patterns, and genomic aberrations, which may reflect incomplete reprogramming and may therefore impact on the regenerative potential of these donor cells in therapies. It also highlights the limitations of current technologies used to generate these cells. Moreover, we provide a systematic review of the state of play with regard to the use of iPSCs in the treatment of neurodegenerative and neuropathological conditions. The

  8. Characteristics of Exemplary Science, Technology, Engineering, and Math (STEM)-Related Experiential Learning Opportunities

    Science.gov (United States)

    Simmons, Jamie Munn

    Experiential opportunities at the secondary level give students the "intimate and necessary relation between the processes of actual experience and education" (Dewey, 1938, p. 19- 20). Career and Technical Education classes (CTE) and co-curricular experiences, one type of experiential learning, underpin and cultivate student curiosity and often channel interests into STEM-related post-secondary disciplines and career choices. There is little existent research on the characteristics of exemplary experiential learning opportunities and the impact on stakeholders. This study is intended to identify the qualities and characteristics of an exemplary secondary experience through the lived experiences of the stakeholders; students, STEM-related teachers, and CTE/STEM Administrators. A qualitative research design was used to examine characteristics and implications for students of four STEM-related programs throughout Virginia. Conclusions from the study include fundamental principles for providing exemplary experiential STEM-related learning opportunities. These principles include: providing hands-on, real world learning opportunities for students, providing learning opportunities that will enhance student ownership in their learning, providing unique and comprehensive career exploration opportunities for students, providing a schedule for teachers that will give them time to plan, deliver, and manage exemplary experiential learning opportunities, providing continual teacher and administrator in-service training relative to planning and implementing exemplary experiential learning opportunities, investing appropriate funds for providing exemplary experiential learning opportunities. Establishing and maintaining active partnerships with business/industry and colleges/universities, and maintaining active advisory communities, providing appropriate staff to support the provision of exemplary experiential learning opportunities is needed. The need for adequate funding

  9. STEM Career Cluster Engineering and Technology Education pathway in Georgia: Perceptions of Georgia engineering and technology education high school teachers and CTAE administrators as measured by the Characteristics of Engineering and Technology Education survey

    Science.gov (United States)

    Crenshaw, Mark VanBuren

    This study examined the perceptions held by Georgia Science, Technology, Engineering, and Mathematics (STEM) Career Cluster Engineering and Technology Education (ETE) high school pathway teachers and Georgia's Career, Technical and Agriculture Education (CTAE) administrators regarding the ETE pathway and its effect on implementation within their district and schools. It provides strategies for ETE teaching methods, curriculum content, STEM integration, and how to improve the ETE pathway program of study. Current teaching and curricular trends were examined in ETE as well as the role ETE should play as related to STEM education. The study, using the Characteristics of Engineering and Technology Education Survey, was conducted to answer the following research questions: (a) Is there a significant difference in the perception of ETE teaching methodology between Georgia ETE high school teachers and CTAE administrators as measured by the Characteristics of Engineering and Technology Education Survey? (b) Is there a significant difference in the perception of ETE curriculum content between Georgia ETE high school teachers and CTAE administrators as measured by the Characteristics of Engineering and Technology Education Survey? (c) Is there a significant difference in the perception of STEM integration in the ETE high school pathway between Georgia ETE high school teachers and CTAE administrators as measured by the Characteristics of Engineering and Technology Education Survey? and (d) Is there a significant difference in the perception of how to improve the ETE high school pathway between Georgia ETE high school teachers and CTAE administrators as measured by the Characteristics of Engineering and Technology Education Survey? Suggestions for further research also were offered.

  10. Conversational sensing

    Science.gov (United States)

    Preece, Alun; Gwilliams, Chris; Parizas, Christos; Pizzocaro, Diego; Bakdash, Jonathan Z.; Braines, Dave

    2014-05-01

    Recent developments in sensing technologies, mobile devices and context-aware user interfaces have made it pos- sible to represent information fusion and situational awareness for Intelligence, Surveillance and Reconnaissance (ISR) activities as a conversational process among actors at or near the tactical edges of a network. Motivated by use cases in the domain of Company Intelligence Support Team (CoIST) tasks, this paper presents an approach to information collection, fusion and sense-making based on the use of natural language (NL) and controlled nat- ural language (CNL) to support richer forms of human-machine interaction. The approach uses a conversational protocol to facilitate a ow of collaborative messages from NL to CNL and back again in support of interactions such as: turning eyewitness reports from human observers into actionable information (from both soldier and civilian sources); fusing information from humans and physical sensors (with associated quality metadata); and assisting human analysts to make the best use of available sensing assets in an area of interest (governed by man- agement and security policies). CNL is used as a common formal knowledge representation for both machine and human agents to support reasoning, semantic information fusion and generation of rationale for inferences, in ways that remain transparent to human users. Examples are provided of various alternative styles for user feedback, including NL, CNL and graphical feedback. A pilot experiment with human subjects shows that a prototype conversational agent is able to gather usable CNL information from untrained human subjects.

  11. Gender Gap in Science, Technology, Engineering, and Mathematics (STEM): Current Knowledge, Implications for Practice, Policy, and Future Directions.

    Science.gov (United States)

    Wang, Ming-Te; Degol, Jessica L

    2017-03-01

    Although the gender gap in math course-taking and performance has narrowed in recent decades, females continue to be underrepresented in math-intensive fields of Science, Technology, Engineering, and Mathematics (STEM). Career pathways encompass the ability to pursue a career as well as the motivation to employ that ability. Individual differences in cognitive capacity and motivation are also influenced by broader sociocultural factors. After reviewing research from the fields of psychology, sociology, economics, and education over the past 30 years, we summarize six explanations for US women's underrepresentation in math-intensive STEM fields: (a) cognitive ability, (b) relative cognitive strengths, (c) occupational interests or preferences, (d) lifestyle values or work-family balance preferences, (e) field-specific ability beliefs, and (f) gender-related stereotypes and biases. We then describe the potential biological and sociocultural explanations for observed gender differences on cognitive and motivational factors and demonstrate the developmental period(s) during which each factor becomes most relevant. We then propose evidence-based recommendations for policy and practice to improve STEM diversity and recommendations for future research directions.

  12. 浮法玻璃品种改换的工艺技术研究%Technology study on Conversion to the Production of Other Float Glass

    Institute of Scientific and Technical Information of China (English)

    李晓青; 王自强; 陈江

    2011-01-01

    运用质量守恒定律和浮法玻璃成形理论,对影响浮法玻璃改换品种的工艺条件进行研究,提出在改换品种时拉引量、主传动、拉边机等关键参数的设计操作原则,通过科学设计改品种程序,实现不同品种间的平稳快速过渡。%Investigation on effect of technology parameters on product-conversion of float glass was carried out by means of the mass conservation law and float glass forming theory.Some design operating rules of daily output,main transmission and edge roller parameters during product conversion were presented.The smooth and rapid transition of production can be realized by scientifically programmed schedule of species conversion.

  13. African American women making race work in science, technology, engineering, and math (STEM)

    Science.gov (United States)

    Galloway, Stephanie Nicole

    African American women maintain distinctive social locations at the intersection of race, gender, and class (Crenshaw, 1991; Collins, 1986; 2000; Wing, 2003). However, their voices, interpretation of experiences, and concern with the use of formal education as a mechanism for racial uplift have not been priorities in feminist movements (hooks, 1981; 1989; Perkins, 1993; Smith, 1998; Spitzack & Carter, 1987). Alternatively, Black feminist thought (Collins, 1990; 2000) is a theory constructed by and for African American women. Given the consequences of pursuing formal education in the histories of African American women and the paucity of African American women represented in STEM fields, the purpose of this study was to (a) reveal how African American women conducting research in STEM disciplines accomplished their professional goals, (b) learn how the women negotiated their multiple identities (i.e. race, gender, and class), (c) link the history of educational experiences among African Americans with agendas for social justice, (d) understand how African American women in STEM align their personal accomplishments with broader agendas for activism in higher education, and (e) discover whether there is a collective identity that successful African American women in STEM share. Using Black feminist thought (Collins, 1986; 2000) and narrative analysis of semi- interviews with eight African American women in STEM, the findings from this study revealed: (a) the women in this study described the challenges of pursuing a career in STEM from a feminist perspective, identifying gender as more significant than race; (b) the women in this study experienced more positive interactions with Black male, White female, and White male mentors than with Black female mentors; (c) the women in this study described the use of empowering strategies for overcoming obstacles in their academic pathways; and (d) their collective academic identities were formed by early interactions with

  14. Coupling between Metacognition and Emotions during STEM Learning with Advanced Learning Technologies: A Critical Analysis, Implications for Future Research, and Design of Learning Systems

    Science.gov (United States)

    Azevedo, Roger; Mudrick, Nicholas; Taub, Michelle; Wortha, Franz

    2017-01-01

    Metacognition and emotions play a critical role in learners' ability to monitor and regulate their learning about 21st-century skills related to science, technology, engineering, and mathematics (STEM) content while using advanced learning technologies (ALTs; e.g., intelligent tutoring systems, serious games, hypermedia, augmented reality). In…

  15. Functionalizing Ascl1 with Novel Intracellular Protein Delivery Technology for Promoting Neuronal Differentiation of Human Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Robinson, Meghan; Chapani, Parv; Styan, Tara; Vaidyanathan, Ranjani; Willerth, Stephanie Michelle

    2016-08-01

    Pluripotent stem cells can become any cell type found in the body. Accordingly, one of the major challenges when working with pluripotent stem cells is producing a highly homogenous population of differentiated cells, which can then be used for downstream applications such as cell therapies or drug screening. The transcription factor Ascl1 plays a key role in neural development and previous work has shown that Ascl1 overexpression using viral vectors can reprogram fibroblasts directly into neurons. Here we report on how a recombinant version of the Ascl1 protein functionalized with intracellular protein delivery technology (Ascl1-IPTD) can be used to rapidly differentiate human induced pluripotent stem cells (hiPSCs) into neurons. We first evaluated a range of Ascl1-IPTD concentrations to determine the most effective amount for generating neurons from hiPSCs cultured in serum free media. Next, we looked at the frequency of Ascl1-IPTD supplementation in the media on differentiation and found that one time supplementation is sufficient enough to trigger the neural differentiation process. Ascl1-IPTD was efficiently taken up by the hiPSCs and enabled rapid differentiation into TUJ1-positive and NeuN-positive populations with neuronal morphology after 8 days. After 12 days of culture, hiPSC-derived neurons produced by Ascl1-IPTD treatment exhibited greater neurite length and higher numbers of branch points compared to neurons derived using a standard neural progenitor differentiation protocol. This work validates Ascl1-IPTD as a powerful tool for engineering neural tissue from pluripotent stem cells.

  16. Why STEM?

    Science.gov (United States)

    Mitts, Charles R.

    2016-01-01

    The International Technology and Engineering Educators Association (ITEEA) defines STEM as a new transdisciplinary subject in schools that integrates the disciplines of science, technology, engineering, and mathematics into a single course of study. There are three major problems with this definition: There is no consensus in support of the ITEEA…

  17. "The good into the pot, the bad into the crop!"--a new technology to free stem cells from feeder cells.

    Directory of Open Access Journals (Sweden)

    Annette Schneider

    Full Text Available A variety of embryonic and adult stem cell lines require an initial co-culturing with feeder cells for non-differentiated growth, self renewal and maintenance of pluripotency. However for many downstream ES cell applications the feeder cells have to be considered contaminations that might interfere not just with the analysis of experimental data but also with clinical application and tissue engineering approaches. Here we introduce a novel technique that allows for the selection of pure feeder-freed stem cells, following stem cell proliferation on feeder cell layers. Complete and reproducible separation of feeder and embryonic stem cells was accomplished by adaptation of an automated cell selection system that resulted in the aspiration of distinct cell colonies or fraction of colonies according to predefined physical parameters. Analyzing neuronal differentiation we demonstrated feeder-freed stem cells to exhibit differentiation potentials comparable to embryonic stem cells differentiated under standard conditions. However, embryoid body growth as well as differentiation of stem cells into cardiomyocytes was significantly enhanced in feeder-freed cells, indicating a feeder cell dependent modulation of lineage differentiation during early embryoid body development. These findings underline the necessity to separate stem and feeder cells before the initiation of in vitro differentiation. The complete separation of stem and feeder cells by this new technology results in pure stem cell populations for translational approaches. Furthermore, a more detailed analysis of the effect of feeder cells on stem cell differentiation is now possible, that might facilitate the identification and development of new optimized human or genetically modified feeder cell lines.

  18. Cognitive and Motivational Factors that Inspire Hispanic Female Students to Pursue STEM-Related Academic Programs that Lead to Careers in Science, Technology, Engineering, and Mathematics

    Science.gov (United States)

    Morel-Baker, Sonaliz

    Hispanics, and women in particular, continue to be underrepresented in the fields of science, technology, engineering, and mathematics (STEM). The purpose of this study was to analyze cognitive and motivational factors that inspired Hispanic female college students to major in STEM programs and aspire to academic success. This mixed methods study was conducted using both quantitative and qualitative data collection and analysis techniques in a sequential phase. Quantitative data were collected through the use of the 80-item Honey and Mumford Learning Styles Questionnaire, which was focused on the students' learning styles and how they impact Hispanic female students upon engaging in a STEM-related curriculum. Qualitative data were collected during interviews focusing on factors that led students to select, participate in, and make a commitment to some aspect of a STEM-related program. The questions that were asked during the interviews were intended to examine whether the existence of role models and STEM initiatives motivate Hispanic female students to major in STEM-related academic programs and aspire to academic success. The participants in this study were undergraduate Hispanic female students majoring in STEM-related academic programs and at a four-year university. The results indicate that the majority of the participants (88%) identified as reflectors, 4% as activists, 4% as theorists, and 4% as pragmatists. The results from the interviews suggested that the existence of role models (family members, educators, or STEM professionals) was a factor that motivated Hispanic females to major in STEM-related subjects and that exposure to STEM initiatives during K-12 education motivated Hispanic females to pursue a career in STEM.

  19. Introduction to thematic minireview series: Development of human therapeutics based on induced pluripotent stem cell (iPSC) technology.

    Science.gov (United States)

    Rao, Mahendra; Gottesfeld, Joel M

    2014-02-21

    With the advent of human induced pluripotent stem cell (hiPSC) technology, it is now possible to derive patient-specific cell lines that are of great potential in both basic research and the development of new therapeutics for human diseases. Not only do hiPSCs offer unprecedented opportunities to study cellular differentiation and model human diseases, but the differentiated cell types obtained from iPSCs may become therapeutics themselves. These cells can also be used in the screening of therapeutics and in toxicology assays for potential liabilities of therapeutic agents. The remarkable achievement of transcription factor reprogramming to generate iPSCs was recognized by the award of the Nobel Prize in Medicine to Shinya Yamanaka in 2012, just 6 years after the first publication of reprogramming methods to generate hiPSCs (Takahashi, K., Tanabe, K., Ohnuki, M., Narita, M., Ichisaka, T., Tomoda, K., and Yamanaka, S. (2007) Cell 131, 861-872). This minireview series highlights both the promises and challenges of using iPSC technology for disease modeling, drug screening, and the development of stem cell therapeutics.

  20. STEM Education.

    Science.gov (United States)

    Xie, Yu; Fang, Michael; Shauman, Kimberlee

    2015-08-01

    Improving science, technology, engineering, and mathematics (STEM) education, especially for traditionally disadvantaged groups, is widely recognized as pivotal to the U.S.'s long-term economic growth and security. In this article, we review and discuss current research on STEM education in the U.S., drawing on recent research in sociology and related fields. The reviewed literature shows that different social factors affect the two major components of STEM education attainment: (1) attainment of education in general, and (2) attainment of STEM education relative to non-STEM education conditional on educational attainment. Cognitive and social psychological characteristics matter for both major components, as do structural influences at the neighborhood, school, and broader cultural levels. However, while commonly used measures of socioeconomic status (SES) predict the attainment of general education, social psychological factors are more important influences on participation and achievement in STEM versus non-STEM education. Domestically, disparities by family SES, race, and gender persist in STEM education. Internationally, American students lag behind those in some countries with less economic resources. Explanations for group disparities within the U.S. and the mediocre international ranking of US student performance require more research, a task that is best accomplished through interdisciplinary approaches.

  1. Flicker noise comparison of direct conversion mixers using Schottky and HBT dioderings in SiGe:C BiCMOS technology

    DEFF Research Database (Denmark)

    Michaelsen, Rasmus Schandorph; Johansen, Tom Keinicke; Tamborg, Kjeld

    2015-01-01

    In this paper, we present flicker noise measurements of two X-band direct conversion mixers implemented in a SiGe:C BiCMOS technology. Both mixers use a ring structure with either Schottky diodes or diode-connected HBTs for double balanced operation. The mixers are packaged in a metal casing on a...... circuit demonstrates a 1/f noise corner frequency around 10 kHz....

  2. Mobile Technology and Mathematics Learning in the Early Grades. Interactive STEM Research + Practice Brief

    Science.gov (United States)

    Presser, Ashley Lewis; Busey, Amy

    2016-01-01

    This research brief describes the value of using mobile technologies in and out of elementary mathematics classrooms, and investigates the view that teachers may not be getting the guidance they need to best leverage those technologies. The authors explore three areas of concern: How can teachers use technology in developmentally appropriate ways…

  3. Too Much of a Good Thing ? Radioisotope Power Conversion Technology and `Waste' Heat in the Titan Environment

    Science.gov (United States)

    Lorenz, Ralph

    Unlike most solar system surface environments, Titan has an atmosphere that is both cold and dense. This means heat transfer to and from a vehicle is determined by convection, rather than by radiation which dominates on Earth and Mars. With surface temperatures near 94K, batteries and systems require heating to operate. Solar power is impractical, so a spacecraft intended to operate for longer than a few hours on Titan must have a radioisotope power source (RPS). Such sources convert heat from Plutonium decay into electricity, with an efficiency that varies from about 5% for thermoelectric systems to 20% for engine cycles such as Stirling. For vehicles with 100-200W electrical power, the 500-4000 W ‘waste’ heat in the Titan environment can be valuable in that it can be exploited to maintain thermal conditions inside the vehicle. The generally benign Titan environment, and the outstanding scientific and popular interest in its exploration, has attracted a number of mission concepts including a lander for Titan’s equatorial dunefields, light gas and hot air (‘Montgolfière’) balloons, airplanes, and capsules that float on its polar seas (e.g. the proposed Titan Mare Explorer.) However, the choice of conversion technology is key to the success of these different platforms. Waste heat can perturb meteorological measurements in several ways. First by creating a warm air plume (an effect observed on Viking and Curiosity.) Second, rain or seaspray falling onto hot radiator surfaces can evaporate causing a local enhancement of methane humidity. Third, sufficiently strong heating could perturb local winds. Similar effects, and the potential generation of effervescence or even fog, may result for capsules floating in liquid hydrocarbons. For landers and drifting buoys, these perturbations may significantly degrade environmental measurements, or at least demand tall meteorology masts, for the higher waste heat output of thermoelectric systems, and a Stirling system

  4. Stem Cell Extracellular Vesicles: Extended Messages of Regeneration

    Science.gov (United States)

    Riazifar, Milad; Pone, Egest J.; Lötvall, Jan; Zhao, Weian

    2017-01-01

    Stem cells are critical to maintaining steady-state organ homeostasis and regenerating injured tissues. Recent intriguing reports implicate extracellular vesicles (EVs) as carriers for the distribution of morphogens and growth and differentiation factors from tissue parenchymal cells to stem cells, and conversely, stem cell–derived EVs carrying certain proteins and nucleic acids can support healing of injured tissues. We describe approaches to make use of engineered EVs as technology platforms in therapeutics and diagnostics in the context of stem cells. For some regenerative therapies, natural and engineered EVs from stem cells may be superior to single-molecule drugs, biologics, whole cells, and synthetic liposome or nanoparticle formulations because of the ease of bioengineering with multiple factors while retaining superior biocompatibility and biostability and posing fewer risks for abnormal differentiation or neoplastic transformation. Finally, we provide an overview of current challenges and future directions of EVs as potential therapeutic alternatives to cells for clinical applications. PMID:27814025

  5. Moving Toward an Anti-Deficit Perspective: African American Science, Technology, Engineering, Mathematics (STEM) Students at Hispanic-Serving Institutions (HSI)

    Science.gov (United States)

    Mahoney, Melissa M.

    The increased demand for qualified STEM workers, necessitates addressing the bachelor's science, technology, engineering and mathematics (STEM) degree achievement among African Americans and other underrepresented populations. Using inquiry derived from Harper's (2010) Anti-Deficit Achievement Framework, this study sought to explore the factors that contribute to the successful degree completion of African American STEM students within a large comprehensive university system. Coding of the twelve semi-structured interviews revealed six major themes: a) K-12/precollege educational experiences, b) motivation to complete a STEM degree, c) systems of social support, d) extracurricular activities and out-of-class experiences, e) addressing stereotyping and discrimination, and f) faculty behaviors and dispositions. All themes were intertwined at each phase of participants' academic careers, thereby, highlighting the complexity of this population's experience and what is needed to address their low STEM degree attainment. Findings indicated that this student population benefits from positive, sustained faculty-student interactions, holistic STEM success programming, and genuine networks of social support. Furthermore, Harper's framework can be modified to explore the motivation of African American STEM students as well as the African American student's relationship with disability support services.

  6. Exploring the undergraduate experience of Latina students in Science, Technology, Engineering, and Mathematics (STEM) majors: Motivators and strategies for achieving baccalaureate attainment

    Science.gov (United States)

    Carbajal, Sandy C.

    Drawing from Latino/a Critical Race Theory and the related Community Cultural Wealth (CCW) model, I concentrate on three forms of CCW---aspirational, navigational, and resistance capital---for this qualitative study on the undergraduate experience of Latina students in Science, Technology, Engineering, and Mathematics (STEM) majors, focusing on strategies and achieving baccalaureate attainment. I interviewed ten Latina students and asked them questions regarding their educational experiences in STEM majors, what contributed to their degree completion, and the strategies they employed for achieving baccalaureate attainment. I identified and described six themes within the study (the underrepresentation of Latinas in STEM majors, the lack of preparation by academic programs for upper division courses, motivators, involvement, time management, and support networks) that, when combined, contributed to participants' degree attainment. This study concludes with implications for policy and practice that would allow universities to better assist Latinas in STEM majors to achieve baccalaureate attainment.

  7. Understanding why women are under-represented in Science, Technology, Engineering and Mathematics (STEM within Higher Education: a regional case study

    Directory of Open Access Journals (Sweden)

    Michael Christie

    Full Text Available Abstract Participation rates of women in Science, Technology, Engineering and Mathematics (STEM is comparatively low and their attrition rates high. An obvious solution is to attract more women to study such subjects. In 2016 the authors undertook research to find out why so few women enrolled in STEM subjects and investigate ways of increasing their recruitment and retention in this area. The informants in our study were enrolled in a tertiary preparation course as well as nursing and education programs. A critique of the literature was used to develop a survey that informed focus group and interview schedules which were used in collecting data. Our study found that many of the factors that hindered women from applying for STEM courses twenty years ago still apply today and recommends actions that can help increase recruitment of women into STEM and assist their retention and graduation in those areas of tertiary education.

  8. Human-Induced Pluripotent Stem Cell Technology and Cardiomyocyte Generation: Progress and Clinical Applications

    Directory of Open Access Journals (Sweden)

    Angela Di Baldassarre

    2018-05-01

    Full Text Available Human-induced pluripotent stem cells (hiPSCs are reprogrammed cells that have hallmarks similar to embryonic stem cells including the capacity of self-renewal and differentiation into cardiac myocytes. The improvements in reprogramming and differentiating methods achieved in the past 10 years widened the use of hiPSCs, especially in cardiac research. hiPSC-derived cardiac myocytes (CMs recapitulate phenotypic differences caused by genetic variations, making them attractive human disease models and useful tools for drug discovery and toxicology testing. In addition, hiPSCs can be used as sources of cells for cardiac regeneration in animal models. Here, we review the advances in the genetic and epigenetic control of cardiomyogenesis that underlies the significant improvement of the induced reprogramming of somatic cells to CMs; the methods used to improve scalability of throughput assays for functional screening and drug testing in vitro; the phenotypic characteristics of hiPSCs-derived CMs and their ability to rescue injured CMs through paracrine effects; we also cover the novel approaches in tissue engineering for hiPSC-derived cardiac tissue generation, and finally, their immunological features and the potential use in biomedical applications.

  9. Human-Induced Pluripotent Stem Cell Technology and Cardiomyocyte Generation: Progress and Clinical Applications.

    Science.gov (United States)

    Di Baldassarre, Angela; Cimetta, Elisa; Bollini, Sveva; Gaggi, Giulia; Ghinassi, Barbara

    2018-05-25

    Human-induced pluripotent stem cells (hiPSCs) are reprogrammed cells that have hallmarks similar to embryonic stem cells including the capacity of self-renewal and differentiation into cardiac myocytes. The improvements in reprogramming and differentiating methods achieved in the past 10 years widened the use of hiPSCs, especially in cardiac research. hiPSC-derived cardiac myocytes (CMs) recapitulate phenotypic differences caused by genetic variations, making them attractive human disease models and useful tools for drug discovery and toxicology testing. In addition, hiPSCs can be used as sources of cells for cardiac regeneration in animal models. Here, we review the advances in the genetic and epigenetic control of cardiomyogenesis that underlies the significant improvement of the induced reprogramming of somatic cells to CMs; the methods used to improve scalability of throughput assays for functional screening and drug testing in vitro; the phenotypic characteristics of hiPSCs-derived CMs and their ability to rescue injured CMs through paracrine effects; we also cover the novel approaches in tissue engineering for hiPSC-derived cardiac tissue generation, and finally, their immunological features and the potential use in biomedical applications.

  10. Disease-in-a-dish: the contribution of patient-specific induced pluripotent stem cell technology to regenerative rehabilitation.

    Science.gov (United States)

    Mack, David L; Guan, Xuan; Wagoner, Ashley; Walker, Stephen J; Childers, Martin K

    2014-11-01

    Advances in regenerative medicine technologies will lead to dramatic changes in how patients in rehabilitation medicine clinics are treated in the upcoming decades. The multidisciplinary field of regenerative medicine is developing new tools for disease modeling and drug discovery based on induced pluripotent stem cells. This approach capitalizes on the idea of personalized medicine by using the patient's own cells to discover new drugs, increasing the likelihood of a favorable outcome. The search for compounds that can correct disease defects in the culture dish is a conceptual departure from how drug screens were done in the past. This system proposes a closed loop from sample collection from the diseased patient, to in vitro disease model, to drug discovery and Food and Drug Administration approval, to delivering that drug back to the same patient. Here, recent progress in patient-specific induced pluripotent stem cell derivation, directed differentiation toward diseased cell types, and how those cells can be used for high-throughput drug screens are reviewed. Given that restoration of normal function is a driving force in rehabilitation medicine, the authors believe that this drug discovery platform focusing on phenotypic rescue will become a key contributor to therapeutic compounds in regenerative rehabilitation.

  11. Positioning Technology and Engineering Education as a Key Force in STEM Education

    Science.gov (United States)

    Strimel, Greg; Grubbs, Michael E.

    2016-01-01

    As the presence of engineering content and practices increases in science education, the distinction between the two fields of science and technology education becomes even more vague than previously theorized. Furthermore, the addition of engineering to the title of the profession raises the question of the true aim of technology education. As a…

  12. Gender Differences in Self-Efficacy and Sense of Class and School Belonging for Majors in Science, Technology, Engineering, and Mathematics (STEM) Disciplines

    Science.gov (United States)

    Hogue, Barbara A.

    Research into women's underrepresentation in science, technology, engineering, and mathematics (STEM) disciplines has become a topic of interest due to the increasing need for employees with technical expertise and a shortage of individuals to fill STEM jobs. The discrepancy in women's representation between STEM and other fields cannot adequately be explained by factors such as women's need to balance work and family (medicine and law are both extremely demanding careers), women's fear of competition (admissions into medical and law schools are highly competitive), or women's inability to excel in science (e.g., entry into medicine requires excellent achievement in the basic sciences). The purpose of this study is to gain a deeper understanding of the role and/or impact a sense of belonging has inside and outside of STEM classrooms. Research questions focused on the role and/or impact of belonging contributes to students' self-efficacy beliefs as a STEM major. Bandura's self-efficacy theory serves as the theoretical framework. Data sources include close-ended surveys of 200 sophomore- and junior-level college students majoring in a STEM discipline. A quantitative exploratory approach allowed participants' responses to be analyzed using both correlation and multiple regression analyses to understand whether a student's sense of belonging is associated with his or her self-efficacy beliefs. Findings suggested that positive support systems impact students' self-efficacy and play a role in fostering students' motivation and decision to major in STEM disciplines. This study contributes to positive social change by providing empirical evidence faculty and administrators may use to promote university-based STEM support programs reflecting the impact belonging has on students' self-efficacy and potentially increasing the number of students majoring in STEM disciplines.

  13. STEAMakers- a global initiative to connect STEM career professionals with the public to inspire the next generation and nurture a creative approach to science, technology, maths & engineering

    Science.gov (United States)

    Shaw, Niamh; Sorkhabi, Elburz; Gasquez, Oriol; Yajima, Saho

    2016-04-01

    STEAMakers is a global initiative founded by Niamh Shaw, Elburz Sorkhabi, Oriol Gasquez & Saho Yajima, four alumni of The International Space University's Space Studies Programme 2015 who each shared a vision to inspire the next generation to embrace science, technology, engineering & maths (STEM) in new ways, by embedding the Arts within STEM, putting the 'A' in STEAM. STEAMakers invited STEM professionals around the world to join their community, providing training and a suite of STEAM events, specially designed to encourage students to perceive science, technology, engineering & maths as a set of tools with which to create, design, troubleshoot, innovate, and imagine. The ultimate goal of STEAMakers is to grow this community and create a global culture of non-linear learning among the next generation, to nurture within them a new multidisciplinary mindset and incubate new forms of innovation and thought leadership required for the future through the power of inspiration and creativity.

  14. Creative Teaching in STEM

    Science.gov (United States)

    Pollard, Vikki; Hains-Wesson, Rachael; Young, Karen

    2018-01-01

    If Science, Technology, Engineering and Mathematics (STEM) disciplines in higher education are to retain students, there needs to be a shift towards teaching in more enriching and interesting ways. Creative teaching needs to become more prominent in STEM. This article presents a study that defines creative teaching in the STEM context and…

  15. Measuring Student Career Interest within the Context of Technology-Enhanced STEM Projects: A Cross-Project Comparison Study Based on the Career Interest Questionnaire

    Science.gov (United States)

    Peterman, Karen; Kermish-Allen, Ruth; Knezek, Gerald; Christensen, Rhonda; Tyler-Wood, Tandra

    2016-01-01

    This article describes Energy for ME and Going Green! Middle Schoolers Out to Save the World, two Science, Technology, Engineering, and Mathematics (STEM) education programs with the common goal of improving students' attitudes about scientific careers. The authors represent two project teams, each with funding from the National Science…

  16. Online Mentoring as an Extracurricular Measure to Encourage Talented Girls in STEM (Science, Technology, Engineering, and Mathematics): An Empirical Study of One-on-One versus Group Mentoring

    Science.gov (United States)

    Stoeger, Heidrun; Hopp, Manuel; Ziegler, Albert

    2017-01-01

    Online mentoring provides an effective means of extracurricular gifted education for talented girls in science, technology, engineering, and mathematics (STEM). Comparative studies on the effectiveness of one-on-one versus group mentoring are lacking, however. The authors investigated this question in the context of a Germany-wide online mentoring…

  17. Development of Analytical Thinking Ability and Attitudes towards Science Learning of Grade-11 Students through Science Technology Engineering and Mathematics (STEM Education) in the Study of Stoichiometry

    Science.gov (United States)

    Chonkaew, Patcharee; Sukhummek, Boonnak; Faikhamta, Chatree

    2016-01-01

    The purpose of this study was to investigate the analytical thinking abilities and attitudes towards science learning of grade-11 students through science, technology, engineering, and mathematics (STEM) education integrated with a problem-based learning in the study of stoichiometry. The research tools consisted of a pre- and post-analytical…

  18. Seamless Genetic Conversion of SMN2 to SMN1 via CRISPR/Cpf1 and Single-Stranded Oligodeoxynucleotides in Spinal Muscular Atrophy Patient-Specific Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Zhou, Miaojin; Hu, Zhiqing; Qiu, Liyan; Zhou, Tao; Feng, Mai; Hu, Qian; Zeng, Baitao; Li, Zhuo; Sun, Qianru; Wu, Yong; Liu, Xionghao; Wu, Lingqian; Liang, Desheng

    2018-05-09

    Spinal muscular atrophy (SMA) is a kind of neuromuscular disease characterized by progressive motor neuron loss in the spinal cord. It is caused by mutations in the survival motor neuron 1 (SMN1) gene. SMN1 has a paralogous gene, survival motor neuron 2 (SMN2), in humans that is present in almost all SMA patients. The generation and genetic correction of SMA patient-specific induced pluripotent stem cells (iPSCs) is a viable, autologous therapeutic strategy for the disease. Here, c-Myc-free and non-integrating iPSCs were generated from the urine cells of an SMA patient using an episomal iPSC reprogramming vector, and a unique crRNA was designed that does not have similar sequences (≤3 mismatches) anywhere in the human reference genome. In situ gene conversion of the SMN2 gene to an SMN1-like gene in SMA-iPSCs was achieved using CRISPR/Cpf1 and single-stranded oligodeoxynucleotide with a high efficiency of 4/36. Seamlessly gene-converted iPSC lines contained no exogenous sequences and retained a normal karyotype. Significantly, the SMN expression and gems localization were rescued in the gene-converted iPSCs and their derived motor neurons. This is the first report of an efficient gene conversion mediated by Cpf1 homology-directed repair in human cells and may provide a universal gene therapeutic approach for most SMA patients.

  19. Learning from our global competitors: A comparative analysis of science, technology, engineering and mathematics (STEM) education pipelines in the United States, Mainland China and Taiwan

    Science.gov (United States)

    Chow, Christina M.

    Maintaining a competitive edge within the 21st century is dependent on the cultivation of human capital, producing qualified and innovative employees capable of competing within the new global marketplace. Technological advancements in communications technology as well as large scale, infrastructure development has led to a leveled playing field where students in the U.S. will ultimately be competing for jobs with not only local, but also international, peers. Thus, the ability to understand and learn from our global competitors, starting with the examination of innovative education systems and best practice strategies, is tantamount to the economic development, and ultimate survival, of the U.S. as a whole. The purpose of this study was to investigate the current state of science, technology, engineering and mathematics (STEM) education and workforce pipelines in the U.S., China, and Taiwan. Two broad research questions examined STEM workforce production in terms of a) structural differences in primary and secondary school systems, including analysis of minimum high school graduation requirements and assessments as well as b) organizational differences in tertiary education and trends in STEM undergraduate and graduate degrees awarded in each region of interest. While each of the systems studied had their relative strengths and weaknesses, each of the Asian economies studied had valuable insights that can be categorized broadly in terms of STEM capacity, STEM interest and a greater understanding of global prospects that led to heightened STEM awareness. In China and Taiwan, STEM capacity was built via both traditional and vocational school systems. Focused and structured curriculum during the primary and early secondary school years built solid mathematics and science skills that translated into higher performance on international assessments and competitions. Differentiated secondary school options, including vocational high school and technical colleges and

  20. ECUT: Energy Conversion and Utilization Technologies program. Industry, university and research interest in the US Department of Energy ECUT biocatalysis research activity

    Science.gov (United States)

    Wilcox, R. E.

    1983-01-01

    The results of a Research Opportunity Notice (RON) disseminated by the Jet Propulsion Laboratory for the U.S. Department of Energy Conversion and Utilization Technologies (ECUT) Program's Biocatalysis Research Activity are presented. The RON was issued in late April of 1983 and solicited expressions of interest from petrochemical and chemical companies, bioengineering firms, biochemical engineering consultants, private research laboratories, and universities for participating in a federal research program to investigate potential applications of biotechnology in producing chemicals. The RON results indicate that broad interest exists within the nation's industry, universities, and research institutes for the Activity and its planned research and development program.

  1. Development of an Interdisciplinary STEM Classroom Activity for Radio Receiver Technology

    Science.gov (United States)

    Davis, Kristina

    2015-01-01

    Introduction The development of a mini STEM-based classroom activity designed to integrate these two fields into one project for middle school aged students is presented here. This lesson involves small groups of students constructing a small AM radio receivers. The lesson surrounding the activity focuses on both the physical nature of electromagnetic and AC waves, circuit design, practical applications to AM radio broadcasting, and research applications of radio telescopes. These tools have shown a significant increase in the lesson's primary concept understanding among 6th grade students, as well as net positive STEM awareness and enthusiasm.Content The primary teaching point for the students to consider and learn during this lesson is 'How does scientific application influence engineering design, and vice versa?' The lesson surrounds the hands-on activity of having students construct their own AM radio receiver. Wave theory and the use of radio instruments for astronomy research are also taught in a traditional lecture format. The activity is designed to complement middle school curriculum, although it has been tested and found suitable for high school and older students as well as the general public.Evaluation and ImpactThe evaluation tool that used for the student groups in this project was a Fryer chart, which is a four panel chart with the main topic listed in the center and a single question in each of the four panels. The students are asked to answer the questions in the chart before and after they participate in the lesson activity, each time in a different colored pencil so that the scores can be given to each student before and after they participated in the activity. Student scores improved from 4.5 to 17.9 out of a total of 20 possible points. This is an overall increase of 67% of the total possible points. The questions asked on the quiz cover the range of wave theory, circuit design, and scientific explanation. This factor of improvement shows that

  2. A New Era of Science Education: Science Teachers' Perceptions and Classroom Practices of Science, Technology, Engineering, and Mathematics (STEM) Integration

    Science.gov (United States)

    Wang, Hui-Hui

    Quality STEM education is the key in helping the United States maintain its lead in global competitiveness and in preparing for new economic and security challenges in the future. Policymakers and professional societies emphasize STEM education by legislating the addition of engineering standards to the existing science standards. On the other hand, the nature of the work of most STEM professionals requires people to actively apply STEM knowledge to make critical decisions. Therefore, using an integrated approach to teaching STEM in K-12 is expected. However, science teachers encounter numerous difficulties in adapting the new STEM integration reforms into their classrooms because of a lack of knowledge and experience. Therefore, high quality STEM integration professional development programs are an urgent necessity. In order to provide these high quality programs, it is important to understand teachers' perceptions and classroom practices regarding STEM integration. A multiple-case study was conducted with five secondary school science teachers in order to gain a better understanding of teachers' perceptions and classroom practices in using STEM integration. This study addresses the following research questions: 1) What are secondary school science teachers' practices of STEM integration? 2) What are secondary science teachers' overall perceptions of STEM integration? and 3) What is the connection between secondary science teachers' perceptions and understanding of STEM integration with their classroom practices? This research aims to explore teachers' perceptions and classroom practices in order to set up the baseline for STEM integration and also to determine STEM integration professional development best practices in science education. Findings from the study provide critical data for making informed decision about the direction for STEM integration in science education in K-12.

  3. Integrating Cognitive Science and Technology Improves Learning in a STEM Classroom

    Science.gov (United States)

    Butler, Andrew C.; Marsh, Elizabeth J.; Slavinsky, J. P.; Baraniuk, Richard G.

    2014-01-01

    The most effective educational interventions often face significant barriers to widespread implementation because they are highly specific, resource intense, and/or comprehensive. We argue for an alternative approach to improving education: leveraging technology and cognitive science to develop interventions that generalize, scale, and can be…

  4. Conversion of adipose-derived stem cells into natural killer-like cells with anti-tumor activities in nude mice.

    Directory of Open Access Journals (Sweden)

    Hongxiu Ning

    Full Text Available Efforts to develop peripheral blood-derived nature killer (NK cells into therapeutic products have been hampered by these cells' low abundance and histoincompatibility. On the other hand, derivation of NK-like cells from more abundant cell sources such as embryonic stem cells (ESCs and umbilical cord blood (UCB requires the selection of rare CD34+ cells. Thus, we sought to convert adipose-derived stem cells (ADSCs, which are abundant and natively CD34+, into NK-like cells. When grown in hematopoietic induction medium, ADSCs formed sphere clusters and expressed hematopoietic markers CD34, CD45, and KDR. Further induction in NK cell-specific medium resulted in a population of cells that expressed NK cell marker CD56, and thus termed ADSC-NK. Alternatively, the hematopoietically induced ADSCs were transduced with NK cell-specific transcription factor E4BP4 prior to induction in NK cell-specific medium. This latter population of cells, termed ADSC-NKE, expressed CD56 and additional NK cell markers such as CD16, CD94, CD158, CD314, FasL, and NKp46. ADSC-NKE was as potent as NK leukemia cell NKL in killing breast cancer cell MCF7 and prostate cancer cells DU145, PC3, LnCap, DuPro, C4-2 and CWR22, but exhibited no killing activity toward normal endothelial and smooth muscle cells. In nude mice test ADSC-NKE was able to significantly delay the progression of tumors formed by MCF7 and PC3. When injected into immunocompetent rats, ADSC-NKE was detectable in bone marrow and spleen for at least 5 weeks. Together, these results suggest that ADSCs can be converted into NK-like cells with anti-tumor activities.

  5. Technology for Obtaining Large Size Complex Oxide Crystals for Experiments on Muon-Electron Conversion Registration in High Energy Physics

    Directory of Open Access Journals (Sweden)

    Gerasymov, Ya.

    2014-11-01

    Full Text Available Technological approaches for qualitative large size scintillation crystals growing based on rare-earth silicates are proposed. A method of iridium crucibles charging using eutectic phase instead of a oxyorthosilicate was developed.

  6. STEM in Afterschool: Changing Perspectives. Shaping Lives. The Impact of Afterschool rograms on Young People's Aspirations and Skills in Science, Technology, Engineering and Mathematics (STEM)

    Science.gov (United States)

    Afterschool Alliance, 2014

    2014-01-01

    After the school bell rings, young people are learning, exploring, making and questioning. Afterschool programs have long influenced students' personal development and supported their social and emotional growth. Today, the afterschool field has enthusiastically embraced STEM as an integral part of their educational offerings. This handout…

  7. Stem Cells

    Science.gov (United States)

    Stem cells are cells with the potential to develop into many different types of cells in the body. ... the body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  8. The Implementation of a One-Day Science, Technology, Engineering and Mathematics (STEM) Career Exploration Workshop for Middle School Girls in Elmira, New York

    Science.gov (United States)

    Turner, Carol-Witkowski CW

    Even now, women are underrepresented in Science, Technology, Engineering, and Mathematics (STEM) careers. The literature shows that one significant approach to address this issue is to work with middle school girls, ages eleven to thirteen, to get them interested and excited about STEM career paths. In addition to appropriate in-school support a review of many different middle school programs indicates that such programs exist in certain service areas but are still missing in others, especially the rural areas. To address this situation, a one-day STEM workshop called "Full STEAHM Ahead!" was implemented spring 2012 in Elmira, New York, to address the career exploration "turning point" for rural middle school girls. The implementation involved pre-workshop, workshop, and post-workshop phases. The success and effectiveness of the workshop was demonstrated by survey comments and verbal feedback from both the girls and educators who attended.

  9. Genetic Tools for Self-Organizing Culture of Mouse Embryonic Stem Cells via Small Regulatory RNA-Mediated Technologies, CRISPR/Cas9, and Inducible RNAi.

    Science.gov (United States)

    Takata, Nozomu; Sakakura, Eriko; Sakuma, Tetsushi; Yamamoto, Takashi

    2017-01-01

    Approaches to investigate gene functions in experimental biology are becoming more diverse and reliable. Furthermore, several kinds of tissues and organs that possess their original identities can be generated in petri dishes from stem cells including embryonic, adult and induced pluripotent stem cells. Researchers now have several choices of experimental methods and their combinations to analyze gene functions in various biological systems. Here, as an example we describe one of the better protocols, which combines three-dimensional embryonic stem cell culture with small regulatory RNA-mediated technologies, clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9), and inducible RNA interference (RNAi). This protocol allows investigation of genes of interest to better understand gene functions in target tissues (or organs) during in vitro development.

  10. Technology Integration Actions in Mathematics teaching in Brazilian Basic Education: Stimulating STEM disciplines

    Directory of Open Access Journals (Sweden)

    Priscila Cadorin Nicolete

    2017-01-01

    Full Text Available A pesar de que la matemática es una habilidad fundamental, la falta de motivación está causando estudiantes brasileños un pobre desempeño en esta disciplina. El trabajo presentado en este documento tiene como objetivo contribuir al desarrollo de diversas prácticas de enseñanza y aprendizaje a través del uso de las Tecnologías de la información y la comunicación (TIC, co n el fin de motivar el estudio de las matemáticas desde los primeros años de educación básica. Las actividades se dividen en dos áreas: un a enfocada en la formación y capacitación de los maestro s y la otra centrada en la integración de tecnologías e n el aula a través del uso del aprendizaje móvil. La experiencia se realizó con niños de 5º año, mediante la enseñanza de los conceptos de fracciones. Las actividades son parte del proyecto denominado " Propuesta de i ntegración de la tecnología e n la enseñanza de disciplinas STEM e n la educación básica pública", co n el apoyo del CNPq - Consejo Nacional de Desarrollo Científico y Tecnológico, y el proyecto "U so de e xperimentación remota en dispositivos móviles para la educación básica e n las escuelas públicas" co n el apoyo de FRIDA ( Fondo Regional para la Innovación Digital en América Latina y el Caribe . En 2011, este proyecto fue seleccionado como uno de los cuatro proyectos más innovadores e n la educación brasileña , en una selección realizada por el Instituto para el Desarrollo y la Innovación Educativa (IDIE de la Organización de Estados Iberoamericanos para la Educación, Ciencia y Cultura (OEI y patrocinado por la Fundación Telefónica.

  11. At Hesitant Doors: The lived experience of women in STEM

    Directory of Open Access Journals (Sweden)

    Romina B. da Costa

    2016-12-01

    Full Text Available This phenomenological investigation aims to explore the lived experience of women in Science, Technology, Engineering and Mathematics (STEM disciplines. As a minority group within a traditionally male-dominated space, women are still underrepresented in the upper echelons of science, even if the number of women in STEM is increasing. The author draws from her experiences as an “undesirable statistic,” a woman who entered college as a STEM student but ended up getting a degree in the social sciences. The author attempts to gain some new insights and understanding of the issue of women in STEM, engaging in two in-depth phenomenological conversations with a female engineering student in a large public university of US Mid-Atlantic region.

  12. Pluripotent stem cells and reprogrammed cells in farm animals.

    Science.gov (United States)

    Nowak-Imialek, Monika; Kues, Wilfried; Carnwath, Joseph W; Niemann, Heiner

    2011-08-01

    Pluripotent cells are unique because of their ability to differentiate into the cell lineages forming the entire organism. True pluripotent stem cells with germ line contribution have been reported for mice and rats. Human pluripotent cells share numerous features of pluripotentiality, but confirmation of their in vivo capacity for germ line contribution is impossible due to ethical and legal restrictions. Progress toward derivation of embryonic stem cells from domestic species has been made, but the derived cells were not able to produce germ line chimeras and thus are termed embryonic stem-like cells. However, domestic animals, in particular the domestic pig (Sus scrofa), are excellent large animals models, in which the clinical potential of stem cell therapies can be studied. Reprogramming technologies for somatic cells, including somatic cell nuclear transfer, cell fusion, in vitro culture in the presence of cell extracts, in vitro conversion of adult unipotent spermatogonial stem cells into germ line derived pluripotent stem cells, and transduction with reprogramming factors have been developed with the goal of obtaining pluripotent, germ line competent stem cells from domestic animals. This review summarizes the present state of the art in the derivation and maintenance of pluripotent stem cells in domestic animals.

  13. Who Chooses STEM Careers? Using A Relative Cognitive Strength and Interest Model to Predict Careers in Science, Technology, Engineering, and Mathematics.

    Science.gov (United States)

    Wang, Ming-Te; Ye, Feifei; Degol, Jessica Lauren

    2017-08-01

    Career aspirations in science, technology, engineering, and mathematics (STEM) are formulated in adolescence, making the high school years a critical time period for identifying the cognitive and motivational factors that increase the likelihood of future STEM employment. While past research has mainly focused on absolute cognitive ability levels in math and verbal domains, the current study tested whether relative cognitive strengths and interests in math, science, and verbal domains in high school were more accurate predictors of STEM career decisions. Data were drawn from a national longitudinal study in the United States (N = 1762; 48 % female; the first wave during ninth grade and the last wave at age 33). Results revealed that in the high-verbal/high-math/high-science ability group, individuals with higher science task values and lower orientation toward altruism were more likely to select STEM occupations. In the low-verbal/moderate-math/moderate-science ability group, individuals with higher math ability and higher math task values were more likely to select STEM occupations. The findings suggest that youth with asymmetrical cognitive ability profiles are more likely to select careers that utilize their cognitive strengths rather than their weaknesses, while symmetrical cognitive ability profiles may grant youth more flexibility in their options, allowing their interests and values to guide their career decisions.

  14. Interactive physics apparatus: influence on interest of secondary school students in pursuing a career path in science, technology, engineering and mathematics (STEM)

    Science.gov (United States)

    Lubrica, Joel V.; Abiasen, Jovalson T.; Dolipas, Bretel B.; Ramos, Jennifer Lyn S.

    2017-01-01

    In this article, we present results of our endeavours as physics educators to facilitate and support pedagogical change and development in the educational system of a developing country, the Philippines. We have discovered that the interaction of junior high school (years 7-10) students with physics apparatus can influence students’ interest in pursuing a career in science, technology, engineering and mathematics (STEM). This assertion stems from self-reports of students who gave their views immediately after their exposure to interactive apparatus in their own school, outside of their usual lessons. Participants claimed that their interest in following a STEM career path was ‘greatly increased’ due to their exposure to these apparatus. This was true even for students who were intending to take a non-STEM career path. Thus, we recommend that, in settings that have constraints involving access to practical equipment, ways to introduce school level interactive physics apparatus to secondary school students be conducted in order to attract more students towards STEM courses. Possibly, policies encouraging this type of exposure should also be formulated.

  15. Survey report for fiscal 1998. Survey of creation of highly efficient renewable resources and bioconversion technologies; 1998 nendo chosa hokokusho. Kokoritsu saisei kano shigen no sosei narabini bio conversion gijutsu ni kansuru chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    A survey is conducted concerning environmentally friendly industrial technologies that utilize renewable resources, which are technologies of creating highly renewable resources and converting renewable resources by breeding industrial vegetation. In relation with the creation technologies, the state of research and development of basic technologies is surveyed, which involves the fabrication of environmental stress resisting vegetation, studies for the application of the gene expression control mechanism, introduction of multigenes and site-directed genes, etc. Concerning the respective target products expected to be produced by industrial vegetation, as much information as possible relative to genes is collected on the current state of production, metabolism in vegetation and microbials, and biosynthesis. Surveyed in relation with the bioconversion technology are the conversion of vegetation-derived polymers, construction of environmentally friendly ligno-bioprocess, conversion of sugar, production of biofuels, etc. Furthermore, the technology of treating ligneous wastes with supercritical water is surveyed, this to determine the practicality of the technology at the current stage. (NEDO)

  16. Technology data for energy plants. Generation of electricity and district heating, energy storage and energy carrier generation and conversion

    Energy Technology Data Exchange (ETDEWEB)

    2012-05-15

    The Danish Energy Agency and Energinet.dk, the Danish electricity transmission and system operator, have at regular intervals published a catalogue of energy producing technologies. The previous edition was published in June 2010. This report presents the results of the most recent update. The primary objective of publishing a technology catalogue is to establish a uniform, commonly accepted and up-to-date basis for energy planning activities, such as future outlooks, evaluations of security of supply and environmental impacts, climate change evaluations, and technical and economic analyses, e.g. on the framework conditions for the development and deployment of certain classes of technologies. With this scope in mind, it has not been the intention to establish a comprehensive catalogue, including all main gasification technologies or all types of electric batteries. Only selected, representative, technologies are included, to enable generic comparisons of e.g. thermal gasification versus combustion of biomass and electricity storage in batteries versus hydro-pumped storage. It has finally been the intention to offer the catalogue for the international audience, as a contribution to similar initiatives aiming at forming a public and concerted knowledge base for international analyses and negotiations. A guiding principle for developing the catalogue has been to rely primarily on well-documented and public information, secondarily on invited expert advice. Since many experts are reluctant in estimating future quantitative performance data, the data tables are not complete, in the sense that most data tables show several blank spaces. This approach has been chosen in order to achieve data, which to some extent are equivalently reliable, rather than to risk a largely incoherent data set including unfounded guesstimates. The current update has been developed with an unbalanced focus, i.e. most attention to technologies which are most essential for current and short

  17. Laminin-521 Promotes Rat Bone Marrow Mesenchymal Stem Cell Sheet Formation on Light-Induced Cell Sheet Technology

    Directory of Open Access Journals (Sweden)

    Zhiwei Jiang

    2017-01-01

    Full Text Available Rat bone marrow mesenchymal stem cell sheets (rBMSC sheets are attractive for cell-based tissue engineering. However, methods of culturing rBMSC sheets are critically limited. In order to obtain intact rBMSC sheets, a light-induced cell sheet method was used in this study. TiO2 nanodot films were coated with (TL or without (TN laminin-521. We investigated the effects of laminin-521 on rBMSCs during cell sheet culturing. The fabricated rBMSC sheets were subsequently assessed to study cell sheet viability, reattachment ability, cell sheet thickness, collagen type I deposition, and multilineage potential. The results showed that laminin-521 could promote the formation of rBMSC sheets with good viability under hyperconfluent conditions. Cell sheet thickness increased from an initial 26.7 ± 1.5 μm (day 5 up to 47.7 ± 3.0 μm (day 10. Moreover, rBMSC sheets maintained their potential of osteogenic, adipogenic, and chondrogenic differentiation. This study provides a new strategy to obtain rBMSC sheets using light-induced cell sheet technology.

  18. Active Learning Strategies: An illustrative approach to bring out better learning outcomes from Science, Technology, Engineering and Mathematics (STEM students

    Directory of Open Access Journals (Sweden)

    Adusumilli Srinath

    2014-10-01

    Full Text Available Teaching in a Teacher centric manner has been the mainframe teaching style in engineering education, however students feel it as a single sided approach and feel they are only passive listeners thus this style has now paved way to a Learner centric style of teaching-learning which is ACTIVE LEARNING, wherein every student is actively involved in one or the other form of learning and thus gets a chance to develop the key aspects of the course either on their own or by being a member of an active-learning group. They thus not only learn and practice the course contents but also learn managerial and team skills which are of much importance in present scenario in regard to Industries and companies where these students will be ultimately hired as employees. Professional education is making one’s students ready for the profession which includes team work, management and technical skills, thus Active learning has emerged as a mainframe tool for cherishing this aim of professional education, especially Science, Technology, Engineering and Management (STEM education. This paper aims to focus on a few facets of this active learning process and give an overview to the teaching faculty as well as students on what their individual roles must be like in this process for getting the most out of this process.

  19. Basic research needs in seven energy-related technologies, conservation, conversion, transmission and storage, environmental fission, fossil, geothermal, and solar

    Energy Technology Data Exchange (ETDEWEB)

    1980-07-01

    This volume comprises seven studies performed by seven groups at seven national laboratories. The laboratories were selected because of their assigned lead roles in research pertaining to the respective technologies. Researches were requested to solicit views of other workers in the fields.

  20. Development of high-level radioactive waste treatment and conversion technologies 'Dry decontamination technology development for highly radioactive contaminants'

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Won Zin; Lee, K. W.; Won, H. J.; Jung, C. J.; Choi, W. K.; Kim, G. N.; Moon, J. K

    2001-04-01

    The followings were studied through the project entitled 'Dry Decontamination Technology Development for Highly Radioactive Contaminants'. 1.Contaminant Characteristics Analysis of Domestic Nuclear Fuel Cycle Projects(NFCP) and Applicability Study of the Unit Dry-Decontamination Techniques A. Classification of contaminated equipments and characteristics analysis of contaminants B. Applicability study of the unit dry-decontamination techniques 2.Performance Evaluation of Unit Dry Decontamination Technique A. PFC decontamination technique B. CO2 decontamination technique C. Plasma decontamination technique 3.Development of Residual Radiation Assessment Methodology for High Radioactive Facility Decontamination A. Development of radioactive nuclide diffusion model on highly radioactive facility structure B. Obtainment of the procedure for assessment of residual radiation dose 4.Establishment of the Design Concept of Dry Decontamination Process Equipment Applicable to Highly Radioactive Contaminants 5.TRIGA soil unit decontamination technology development A. Development of soil washing and flushing technologies B. Development of electrokinetic soil decontamination technology.

  1. A Review of Science, Technology, Engineering & Mathematics (STEM) Education Research from 1999-2013: A Malaysian Perspective

    Science.gov (United States)

    Jayarajah, Kamaleswaran; Saat, Rohaida Mohd; Rauf, Rose Amnah Abdul

    2014-01-01

    The purpose of this study is to explore the research base of STEM education in Malaysia through an analysis review of articles for a 14-year period, from 1999 to 2013. The research base review focuses on identifying four characteristics of STEM education: a) temporal distribution, b) the research areas involved in each discipline, c) the types of…

  2. Availability of advanced foreign energy conversion and conservation technology for use in the United States. Biennial report

    Energy Technology Data Exchange (ETDEWEB)

    Straus, R W; Thurman, R S; Carsey, J N; Fujishima, C; Hammel, J; Dietrich, P; Pfeil, R; Bottomley, K

    1978-12-01

    The assignment by DOE requested Galaxy to, Review and evaluate all field data and to define areas where foreign work is ready to be implemented by US; areas where US work might be dropped since foreign R and D is more advanced; areas where foreign R and D indicate sufficient promise for the US to initiate work in; areas where cooperative R and D ventures or licensing agreements might prove beneficial, etc. The specific technologies to be investigated by Galaxy were set forth in Tasks I and V of the contract as follows: Task I: (A) waste heat utilization, (B) advanced cycles, (C) component reliability and efficiency, (D) heat transfer, and (E) combustion and materials; Task V: (A) controls and process efficiency; (B) materials and fabrication; (C) components and heat engines; (D) thermodynamics and heat transfer; (E) fuel cells; (F) combustion and alternate fuels; and (G) heat utilization, planning and analysis. The foreign technology is briefly identified within the areas set forth. (WHK)

  3. Measuring Student Career Interest within the Context of Technology-Enhanced STEM Projects: A Cross-Project Comparison Study Based on the Career Interest Questionnaire

    Science.gov (United States)

    Peterman, Karen; Kermish-Allen, Ruth; Knezek, Gerald; Christensen, Rhonda; Tyler-Wood, Tandra

    2016-12-01

    This article describes Energy for ME and Going Green! Middle Schoolers Out to Save the World, two Science, Technology, Engineering, and Mathematics (STEM) education programs with the common goal of improving students' attitudes about scientific careers. The authors represent two project teams, each with funding from the National Science Foundation's ITEST program. Using different approaches and technology, both projects challenged students to use electricity monitoring system data to create action plans for conserving energy in their homes and communities. The impact of each project on students' career interests was assessed via a multi-method evaluation that included the Career Interest Questionnaire (CIQ), a measure that was validated within the context of ITEST projects and has since become one of the instruments used most commonly across the ITEST community. This article explores the extent to which the CIQ can be used to document the effects of technology-enhanced STEM educational experiences on students' career attitudes and intentions in different environments. The results indicate that the CIQ, and the Intent subscale in particular, served as significant predictors of students' self-reported STEM career aspirations across project context. Results from each project also demonstrated content gains by students and demonstrated the impact of project participation and gender on student outcomes. The authors conclude that the CIQ is a useful tool for providing empirical evidence to document the impact of technology-enhanced science education programs, particularly with regard to Intent to purse a STEM career. The need for additional cross-project comparison studies is also discussed.

  4. Utilization of excess weapon plutonium: scientific and technological aspects of the conversion of military capacities for civilian use and sustainable development

    International Nuclear Information System (INIS)

    Winkelmann, H.-P.

    1996-01-01

    The scientific and technological aspects of the conversion of military capacities for civilian use and sustainable development concerning the utilisation of excess weapon plutonium consist of the following main issues: The new understanding of 'security'; industrial restructuring for sustainable development; human resources issues; cleaning up of the world legacy; developing timely alternate use plans for military facilities. The issues and problems of nuclear disarmament management are linked to sustainable development and are related to safe and environmentally sound management of radioactive wastes, meaning also safe transport, storage and disposal with a view to protect human health and the environment. Special emphasis is laid on the international and regional cooperation as the main basis for action

  5. Uranium conversion

    International Nuclear Information System (INIS)

    Oliver, Lena; Peterson, Jenny; Wilhelmsen, Katarina

    2006-03-01

    FOI, has performed a study on uranium conversion processes that are of importance in the production of different uranium compounds in the nuclear industry. The same conversion processes are of interest both when production of nuclear fuel and production of fissile material for nuclear weapons are considered. Countries that have nuclear weapons ambitions, with the intention to produce highly enriched uranium for weapons purposes, need some degree of uranium conversion capability depending on the uranium feed material available. This report describes the processes that are needed from uranium mining and milling to the different conversion processes for converting uranium ore concentrate to uranium hexafluoride. Uranium hexafluoride is the uranium compound used in most enrichment facilities. The processes needed to produce uranium dioxide for use in nuclear fuel and the processes needed to convert different uranium compounds to uranium metal - the form of uranium that is used in a nuclear weapon - are also presented. The production of uranium ore concentrate from uranium ore is included since uranium ore concentrate is the feed material required for a uranium conversion facility. Both the chemistry and principles or the different uranium conversion processes and the equipment needed in the processes are described. Since most of the equipment that is used in a uranium conversion facility is similar to that used in conventional chemical industry, it is difficult to determine if certain equipment is considered for uranium conversion or not. However, the chemical conversion processes where UF 6 and UF 4 are present require equipment that is made of corrosion resistant material

  6. Conversation Analysis.

    Science.gov (United States)

    Schiffrin, Deborah

    1990-01-01

    Summarizes the current state of research in conversation analysis, referring primarily to six different perspectives that have developed from the philosophy, sociology, anthropology, and linguistics disciplines. These include pragmatics; speech act theory; interactional sociolinguistics; ethnomethodology; ethnography of communication; and…

  7. Design-based online teacher professional development to introduce integration of STEM in Pakistan

    Science.gov (United States)

    Anwar, Tasneem

    In today's global society where innovations spread rapidly, the escalating focus on science, technology, engineering and mathematics (STEM) has quickly intensified in the United States, East Asia and much of Western Europe. Our ever-changing, increasingly global society faces many multidisciplinary problems, and many of the solutions require the integration of multiple science, technology, engineering, and mathematics (STEM) concepts. Thus, there is a critical need to explore the integration of STEM subjects in international education contexts. This dissertation study examined the exploration of integration of STEM in the unique context of Pakistan. This study used three-phase design-based methodological framework derived from McKenney and Reeves (2012) to explore the development of a STEM focused online teacher professional development (oTPD-STEM) and to identify the design features that facilitate teacher learning. The oTPD-STEM program was designed to facilitate eight Pakistani elementary school teachers' exploration of the new idea of STEM integration through both practical and theoretical considerations. This design-based study employed inductive analysis (Strauss and Corbin, 1998) to analyze multiple data sources of interviews, STEM perception responses, reflective learning team conversations, pre-post surveys and artifacts produced in oTPD-STEM. Findings of this study are presented as: (1) design-based decisions for oTPD-STEM, and (2) evolution in understanding of STEM by sharing participant teachers' STEM model for Pakistani context. This study advocates for the potential of school-wide oTPD for interdisciplinary collaboration through support for learner-centered practices.

  8. Global Collaborative STEM Education

    Science.gov (United States)

    Meabh Kelly, Susan; Smith, Walter

    2016-04-01

    Global Collaborative STEM Education, as the name suggests, simultaneously supports two sets of knowledge and skills. The first set is STEM -- science, technology, engineering and math. The other set of content knowledge and skills is that of global collaboration. Successful global partnerships require awareness of one's own culture, the biases embedded within that culture, as well as developing awareness of the collaborators' culture. Workforce skills fostered include open-mindedness, perseverance when faced with obstacles, and resourceful use of technological "bridges" to facilitate and sustain communication. In respect for the 2016 GIFT Workshop focus, Global Collaborative STEM Education projects dedicated to astronomy research will be presented. The projects represent different benchmarks within the Global Collaborative STEM Education continuum, culminating in an astronomy research experience that fully reflects how the global STEM workforce collaborates. To facilitate wider engagement in Global Collaborative STEM Education, project summaries, classroom resources and contact information for established international collaborative astronomy research projects will be disseminated.

  9. Engaging Historically Black Colleges and Universities through Science, Technology, Engineering and Math (STEM) Education and Community Engagement

    Science.gov (United States)

    EPA’s STEM Outreach Program in RTP began in 2004, with the aim of supporting EPA’s mission of protecting human health and the environment by increasing awareness, providing education, and inspiring the public, especially K-12 students.

  10. Modeling the mitochondrial cardiomyopathy of Barth syndrome with induced pluripotent stem cell and heart-on-chip technologies

    NARCIS (Netherlands)

    Wang, Gang; McCain, Megan L.; Yang, Luhan; He, Aibin; Pasqualini, Francesco Silvio; Agarwal, Ashutosh; Yuan, Hongyan; Jiang, Dawei; Zhang, Donghui; Zangi, Lior; Geva, Judith; Roberts, Amy E.; Ma, Qing; Ding, Jian; Chen, Jinghai; Wang, Da-Zhi; Li, Kai; Wang, Jiwu; Wanders, Ronald J. A.; Kulik, Wim; Vaz, Frédéric M.; Laflamme, Michael A.; Murry, Charles E.; Chien, Kenneth R.; Kelley, Richard I.; Church, George M.; Parker, Kevin Kit; Pu, William T.

    2014-01-01

    Study of monogenic mitochondrial cardiomyopathies may yield insights into mitochondrial roles in cardiac development and disease. Here, we combined patient-derived and genetically engineered induced pluripotent stem cells (iPSCs) with tissue engineering to elucidate the pathophysiology underlying

  11. Clean Fuel, Clean Energy Conversion Technology: Experimental and Numerical Investigation of Palm Oil Mill Effluent Biogas Flameless Combustion

    Directory of Open Access Journals (Sweden)

    Seyed Ehsan Hosseini

    2015-08-01

    Full Text Available The combustion of effluent biogas from a palm oil mill is not feasible on a large scale because of its low calorific value (LCV. Therefore, the captured biogas is usually flared because of a lack of appropriate combustion technology. However, such biogas could be an excellent source of energy for combined heat and power (CHP generation in palm oil mills. In this paper, the feasibility of using biogas from palm oil mills in flameless combustion systems is investigated. In computational fluid dynamic (CFD modeling, a two-step reaction scheme is employed to simulate the eddy dissipation method (EDM. In such biogas flameless combustion, the temperature inside the chamber is uniform and hot spots are eliminated. The peak of the non-luminous flame volume and the maximum temperature uniformity occur under stoichiometric conditions when the concentration of oxygen in the oxidizer is 7%. In these conditions, as the concentration of oxygen in the oxidizer increases, the efficiency of palm oil mill effluent biogas flameless combustion increases. The maximum efficiency (around 61% in the experiment is achieved when the percentage of oxygen in the oxidizer is 7%.

  12. Conversational flow promotes solidarity.

    Science.gov (United States)

    Koudenburg, Namkje; Postmes, Tom; Gordijn, Ernestine H

    2013-01-01

    Social interaction is fundamental to the development of various aspects of "we-ness". Previous research has focused on the role the content of interaction plays in establishing feelings of unity, belongingness and shared reality (a cluster of variables referred to as solidarity here). The present paper is less concerned with content, but focuses on the form of social interaction. We propose that the degree to which conversations flow smoothly or not is, of itself, a cue to solidarity. We test this hypothesis in samples of unacquainted and acquainted dyads who communicate via headsets. Conversational flow is disrupted by introducing a delay in the auditory feedback (vs. no delay). Results of three studies show that smoothly coordinated conversations (compared with disrupted conversations and a control condition) increase feelings of belonging and perceptions of group entitativity, independently of conversation content. These effects are driven by the subjective experience of conversational flow. Our data suggest that this process occurs largely beyond individuals' control. We conclude that the form of social interaction is a powerful cue for inferring group solidarity. Implications for the impact of modern communication technology on developing a shared social identity are discussed.

  13. Conversational flow promotes solidarity.

    Directory of Open Access Journals (Sweden)

    Namkje Koudenburg

    Full Text Available Social interaction is fundamental to the development of various aspects of "we-ness". Previous research has focused on the role the content of interaction plays in establishing feelings of unity, belongingness and shared reality (a cluster of variables referred to as solidarity here. The present paper is less concerned with content, but focuses on the form of social interaction. We propose that the degree to which conversations flow smoothly or not is, of itself, a cue to solidarity. We test this hypothesis in samples of unacquainted and acquainted dyads who communicate via headsets. Conversational flow is disrupted by introducing a delay in the auditory feedback (vs. no delay. Results of three studies show that smoothly coordinated conversations (compared with disrupted conversations and a control condition increase feelings of belonging and perceptions of group entitativity, independently of conversation content. These effects are driven by the subjective experience of conversational flow. Our data suggest that this process occurs largely beyond individuals' control. We conclude that the form of social interaction is a powerful cue for inferring group solidarity. Implications for the impact of modern communication technology on developing a shared social identity are discussed.

  14. The Hidden STEM Economy

    Science.gov (United States)

    Rothwell, Jonathan

    2013-01-01

    Workers in STEM (science, technology, engineering, and math) fields play a direct role in driving economic growth. Yet, because of how the STEM economy has been defined, policymakers have mainly focused on supporting workers with at least a bachelor's (BA) degree, overlooking a strong potential workforce of those with less than a BA. This report…

  15. What drives the gender gap in STEM? The SAGA Science, Technology and Innovation Gender Objectives List (STI GOL) as a new approach to linking indicators to STI policies

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, E.; Schaaper, M.; Bello, A.

    2016-07-01

    There is a large imbalance in the participation of women in Science, Technology, Engineering and Mathematics (STEM) fields across all of Latin American countries despite the fact that the region has one of the highest proportions of female researchers worldwide (44% according to UIS statistics). Female researchers face persisting institutional and cultural barriers, which limit the development of their careers and constrains their access to decision-making positions. In this framework, UNESCO has launched the STEM and Gender Advancement (SAGA) project, which has for objective to address the gender gap in STEM fields in all countries at all levels of education and research as well as to promote women’s participation in science. SAGA is a global UNESCO project with the support of the Swedish Government through the Swedish International Development Cooperation Agency (Sida). One of the outcomes of this project is the SAGA Science, Technology and Innovation Gender Objectives List (STI GOL), which is an innovative tool that aids in the identification of gaps in the policy mix. Additionally, the STI GOL configures the conceptual backbone of the SAGA project, by linking gender equality STI policy instruments with indicators. By using the STI GOL, and identifying the gender gaps, policy-makers will be able to implement evidence-based policies in STEM fields. The SAGA STI GOL is a new and innovative way of contributing to the development of effective gender sensitive policies in STI fields, both in education and in the workplace. Likewise, it enables the categorization of STI policies and instruments, with the objective of identifying gaps in the policy mix and aid in the creation and design of evidence-based public policies to promote gender equality. (Author)

  16. Mathematical learning instruction and teacher motivation factors affecting science technology engineering and math (STEM) major choices in 4-year colleges and universities: Multilevel structural equation modeling

    Science.gov (United States)

    Lee, Ahlam

    2011-12-01

    Using the Educational Longitudinal Study of 2002/06, this study examined the effects of the selected mathematical learning and teacher motivation factors on graduates' science, technology, engineering, and math (STEM) related major choices in 4-year colleges and universities, as mediated by math performance and math self-efficacy. Using multilevel structural equation modeling, I analyzed: (1) the association between mathematical learning instruction factors (i.e., computer, individual, and lecture-based learning activities in mathematics) and students' STEM major choices in 4-year colleges and universities as mediated by math performance and math self-efficacy and (2) the association between school factor, teacher motivation and students' STEM major choices in 4-year colleges and universities via mediators of math performance and math self-efficacy. The results revealed that among the selected learning experience factors, computer-based learning activities in math classrooms yielded the most positive effects on math self-efficacy, which significantly predicted the increase in the proportion of students' STEM major choice as mediated by math self-efficacy. Further, when controlling for base-year math Item Response Theory (IRT) scores, a positive relationship between individual-based learning activities in math classrooms and the first follow-up math IRT scores emerged, which related to the high proportion of students' STEM major choices. The results also indicated that individual and lecture-based learning activities in math yielded positive effects on math self-efficacy, which related to STEM major choice. Concerning between-school levels, teacher motivation yielded positive effects on the first follow up math IRT score, when controlling for base year IRT score. The results from this study inform educators, parents, and policy makers on how mathematics instruction can improve student math performance and encourage more students to prepare for STEM careers. Students

  17. Pictorial Conversations.

    Science.gov (United States)

    Hooper, Kristina

    1982-01-01

    Provides the rationale for considering communication in a graphic domain and suggests a specific goal for designing work stations which provide graphic capabilities in educational settings. The central element of this recommendation is the "pictorial conversation", a highly interactive exchange that includes pictures as the central elements.…

  18. Integrative STEM Education Defined

    OpenAIRE

    Sanders, Mark E.

    2015-01-01

    “My work with integrative STEM education began in 1990 with the NSF-funded Technology, Science, Mathematics Integration Project… By 2008, I was convinced “STEM Education” was (and always would be) a hopelessly ambiguous phrase, and therefore felt we absolutely needed to rename our “STEM Education” graduate program and develop a tight operational definition of the central idea underlying our program, in hopes of preventing the sort of hopeless ambiguity that ruined the term “STEM education” fr...

  19. Innovation and STEM Schools

    Science.gov (United States)

    Roberts, Julia Link

    2015-01-01

    How do schools with a focus on science, technology, engineering, and mathematics (STEM) fit in with state goals to increase innovation and to boost the economy? This article briefly discusses how educators can encourage creativity and innovation.

  20. Biomass thermochemical conversion program: 1987 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Schiefelbein, G.F.; Stevens, D.J.; Gerber, M.A.

    1988-01-01

    The objective of the Biomass Thermochemical Conversion Program is to generate a base of scientific data and conversion process information that will lead to establishment of cost-effective processes for conversion of biomass resources into clean fuels. To accomplish this objective, in fiscal year 1987 the Thermochemical Conversion Program sponsored research activities in the following four areas: Liquid Hydrocarbon Fuels Technology; Gasification Technology; Direct Combustion Technology; Program Support Activities. In this report an overview of the Thermochemical Conversion Program is presented. Specific research projects are then described. Major accomplishments for 1987 are summarized.

  1. Biomass thermochemical conversion program. 1985 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Schiefelbein, G.F.; Stevens, D.J.; Gerber, M.A.

    1986-01-01

    Wood and crop residues constitute a vast majority of the biomass feedstocks available for conversion, and thermochemical processes are well suited for conversion of these materials. The US Department of Energy (DOE) is sponsoring research on this conversion technology for renewable energy through its Biomass Thermochemical Conversion Program. The Program is part of DOE's Biofuels and Municipal Waste Technology Division, Office of Renewable Technologies. This report briefly describes the Thermochemical Conversion Program structure and summarizes the activities and major accomplishments during fiscal year 1985. 32 figs., 4 tabs.

  2. The stem factor challenge

    International Nuclear Information System (INIS)

    Russell, M.J.; Steele, R. Jr.; DeWall, K.G.; Watkins, J.C.; Bramwell, D.

    1994-01-01

    One of the most important challenges that still needs to be met in the effort to understand the operation of motor-operated, rising-stem valves is the ability to determine stem factor throughout the valve's load range. The stem factor represents the conversion of operator torque to stem thrust. Determining the stem factor is important because some motor-operated valves (MOVs) cannot be tested in the plant at design basis conditions. The ability of these valves to perform their design basis function (typically, to operate against specified flow and pressure loads) must be ensured by analytical methods or by extrapolating from the results of tests conducted at lower loads. Because the stem factor tends to vary in response to friction and lubrication phenomena that occur during loading and wedging, analytical methods and extrapolation methods have been difficult to develop and implement. Early investigations into variability in the stem factor tended to look only at the tip of the iceberg; they focused on what was happening at torque switch trip, which usually occurs at full wedging. In most stems, the stem factor is better (lower) in the wedging transient than before wedging, so working with torque switch trip data alone led many early researchers to false conclusions about the relationship between stem factor and load. However, research at the Idaho National Engineering Laboratory (INEL) has taken a closer look at what happens during the running portion of the closing stroke along with the wedging portion. This shift in focus is important, because functional failure of a valve typically consists of a failure to isolate flow, not a failure to achieve full wedging. Thus, the stem factor that must be determined for a valve's design basis closing requirements is the one that corresponds with the running load before wedging

  3. [The bioethics law revision: comparative analysis of contributions from different public and professional offices. Assisted Reproductive Technology, embryo and stem cells research, umbilical cord blood bank].

    Science.gov (United States)

    Merviel, P; Cabry, R; Lourdel, E; Brasseur, F; Devaux, A; Copin, H

    2009-09-01

    The revision of the bioethics law of 2004 must occur in a five year's time. For this revision, the authorities decided to organize general states of bioethics and requested the production of contributions by the companies, institutions or associations. These texts tackle various subjects, like the Assisted Reproductive Technologies, research on the embryo and the stem cells and the banks of umbilical cord blood. Certain opinions converge, others differ, but all take part in the great debate which will take place at the time of the general conference.

  4. Promoting Students' Problem Solving Skills and Knowledge of STEM Concepts in a Data-Rich Learning Environment: Using Online Data as a Tool for Teaching about Renewable Energy Technologies

    Science.gov (United States)

    Thurmond, Brandi

    2011-01-01

    This study sought to compare a data-rich learning (DRL) environment that utilized online data as a tool for teaching about renewable energy technologies (RET) to a lecture-based learning environment to determine the impact of the learning environment on students' knowledge of Science, Technology, Engineering, and Math (STEM) concepts related…

  5. Quantum conversion

    OpenAIRE

    Mazilu, Michael

    2015-01-01

    ICOAM 2015 The electromagnetic momentum transferred transferred to scattering particles is proportional to the intensity of the incident fields, however, the momentum of single photons ℏk does not naturally appear in these classical expressions. Here, we discuss an alternative to Maxwell's stress tensor that renders the classical electromagnetic field momentum compatible to the quantum mechanical one. This is achieved through the introduction of the quantum conversion which allows the tran...

  6. Conversational sensemaking

    Science.gov (United States)

    Preece, Alun; Webberley, Will; Braines, Dave

    2015-05-01

    Recent advances in natural language question-answering systems and context-aware mobile apps create opportunities for improved sensemaking in a tactical setting. Users equipped with mobile devices act as both sensors (able to acquire information) and effectors (able to act in situ), operating alone or in collectives. The currently- dominant technical approaches follow either a pull model (e.g. Apple's Siri or IBM's Watson which respond to users' natural language queries) or a push model (e.g. Google's Now which sends notifications to a user based on their context). There is growing recognition that users need more flexible styles of conversational interaction, where they are able to freely ask or tell, be asked or told, seek explanations and clarifications. Ideally such conversations should involve a mix of human and machine agents, able to collaborate in collective sensemaking activities with as few barriers as possible. Desirable capabilities include adding new knowledge, collaboratively building models, invoking specific services, and drawing inferences. As a step towards this goal, we collect evidence from a number of recent pilot studies including natural experiments (e.g. situation awareness in the context of organised protests) and synthetic experiments (e.g. human and machine agents collaborating in information seeking and spot reporting). We identify some principles and areas of future research for "conversational sensemaking".

  7. [Progress in stem cells and regenerative medicine].

    Science.gov (United States)

    Wang, Libin; Zhu, He; Hao, Jie; Zhou, Qi

    2015-06-01

    Stem cells have the ability to differentiate into all types of cells in the body and therefore have great application potential in regenerative medicine, in vitro disease modelling and drug screening. In recent years, stem cell technology has made great progress, and induced pluripotent stem cell technology revolutionizes the whole stem cell field. At the same time, stem cell research in our country has also achieved great progress and becomes an indispensable power in the worldwide stem cell research field. This review mainly focuses on the research progress in stem cells and regenerative medicine in our country since the advent of induced pluripotent stem cell technology, including induced pluripotent stem cells, transdifferentiation, haploid stem cells, and new gene editing tools.

  8. Learning for STEM Literacy: STEM Literacy for Learning

    Science.gov (United States)

    Zollman, Alan

    2012-01-01

    We are in the STEM generation whose comprehensive purpose is to resolve (1) societal needs for new technological and scientific advances; (2) economic needs for national security; and (3) personal needs to become a fulfilled, productive, knowledgeable citizen. STEM specifically refers to science, technology, engineering, and mathematics, but now…

  9. The Current Status of STEM Education Research

    Science.gov (United States)

    Brown, Josh

    2012-01-01

    This paper explores the current Science, Technology, Engineering and Mathematics (STEM) education research base through an analysis of articles from eight journals focused on the STEM disciplines. Analyzed are both practitioner and research publications to determine the current scope of STEM education research, where current STEM education…

  10. Germany as a Study Abroad Destination of U.S. Students in the Science, Technology, Engineering and Mathematics (STEM) Fields

    Science.gov (United States)

    Comp, David

    2010-01-01

    Of the 205,000 U.S. students abroad during the 2004-2005 academic year, only 6,557 or slightly more than 3% of them studied in Germany. The Ohio Alliance reports that only 13% of all U.S. students who studied abroad during the 2004-2005 academic year were from the STEM fields of study. The Institute of International Education Open Doors Report,…

  11. FY 2000 report on the results of the survey on the biomass-derived energy conversion technology. III; 2000 nendo biomass shigen wo genryo to suru energy henkan gijutsu ni kansuru chosa. 3

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    In relation to the biomass-derived energy conversion technology which was regarded as promising from the results of the survey already made, the survey was made on the present situation and subjects of the technical development, social needs, energy efficiency, economical efficiency and the future. Studies were conducted on the development of technology for effective biomass utilization and the conceptual design and evaluation of a system for effective biomass utilization. As to the effective biomass utilization technology, the survey was made on the biomass combustion power generation technology/gasification power generation technology, gasification methanol synthesis of biomass, biomass gasification dimethyl ether synthesis, technology of ethanol production by alcohol fermentation via saccharification of biomass, methy-esterification of grease biomass, especially palm oil, and diesel oil production via reformation of by-product glycerin, and energy production from biomass using super- (sub- ) critical reaction. As to the system for effective biomass utilization, the survey was carried out of the regional outline, resource amount and sampling amount, selection of the conversion technology, and economical efficiency of Takatsuki city, Osaka, Shimokawa town, Hokkaido, Yufutsu/Hidaka region, Hokkaido, and Aogaki town, Hyogo. (NEDO)

  12. Report on a survey in fiscal 1999. Part 2. Survey on the biomass-derived energy conversion technology; 1999 nendo biomass shigen wo genryo to suru energy henkan gijutsu ni kansuru chosa hokokusho. 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    Biomass energy is positioned as a promising environment harmonizing energy in the 21st century because it does not break down the CO2 balance in the global scale. The present survey has investigated quantity of biomass resources utilizable as energy resources, investigated and analyzed the biomass-derived energy conversion technology, searched for a promising practically usable technology, and discussed the means to achieve the technological introduction. The foreword chapter describes that now is the good time to recognize importance of and introduce the biomass-derived technology. First and second chapters estimate energy potential and utilizable quantity of wastes-based biomass in Indonesia, Malaysia, the Philippines, and Brazil. Chapter 3 investigates feasibility of methane fermentation and ethanol fermentation as a promising bio-chemical conversion process. Chapter 4 has performed feasibility studies on biomass electric power generation, methanol synthesis by gasification, thermal decomposition and gasification as promising thermo-chemical conversion processes. Chapter 5 proposed a biomass electric power generation system, a biomass-gasified methanol synthesizing system, and a dimethyl ether production system. (NEDO)

  13. Predictability of Conversation Partners

    Science.gov (United States)

    Takaguchi, Taro; Nakamura, Mitsuhiro; Sato, Nobuo; Yano, Kazuo; Masuda, Naoki

    2011-08-01

    Recent developments in sensing technologies have enabled us to examine the nature of human social behavior in greater detail. By applying an information-theoretic method to the spatiotemporal data of cell-phone locations, [C. Song , ScienceSCIEAS0036-8075 327, 1018 (2010)] found that human mobility patterns are remarkably predictable. Inspired by their work, we address a similar predictability question in a different kind of human social activity: conversation events. The predictability in the sequence of one’s conversation partners is defined as the degree to which one’s next conversation partner can be predicted given the current partner. We quantify this predictability by using the mutual information. We examine the predictability of conversation events for each individual using the longitudinal data of face-to-face interactions collected from two company offices in Japan. Each subject wears a name tag equipped with an infrared sensor node, and conversation events are marked when signals are exchanged between sensor nodes in close proximity. We find that the conversation events are predictable to a certain extent; knowing the current partner decreases the uncertainty about the next partner by 28.4% on average. Much of the predictability is explained by long-tailed distributions of interevent intervals. However, a predictability also exists in the data, apart from the contribution of their long-tailed nature. In addition, an individual’s predictability is correlated with the position of the individual in the static social network derived from the data. Individuals confined in a community—in the sense of an abundance of surrounding triangles—tend to have low predictability, and those bridging different communities tend to have high predictability.

  14. Predictability of Conversation Partners

    Directory of Open Access Journals (Sweden)

    Taro Takaguchi

    2011-09-01

    Full Text Available Recent developments in sensing technologies have enabled us to examine the nature of human social behavior in greater detail. By applying an information-theoretic method to the spatiotemporal data of cell-phone locations, [C. Song et al., Science 327, 1018 (2010SCIEAS0036-8075] found that human mobility patterns are remarkably predictable. Inspired by their work, we address a similar predictability question in a different kind of human social activity: conversation events. The predictability in the sequence of one’s conversation partners is defined as the degree to which one’s next conversation partner can be predicted given the current partner. We quantify this predictability by using the mutual information. We examine the predictability of conversation events for each individual using the longitudinal data of face-to-face interactions collected from two company offices in Japan. Each subject wears a name tag equipped with an infrared sensor node, and conversation events are marked when signals are exchanged between sensor nodes in close proximity. We find that the conversation events are predictable to a certain extent; knowing the current partner decreases the uncertainty about the next partner by 28.4% on average. Much of the predictability is explained by long-tailed distributions of interevent intervals. However, a predictability also exists in the data, apart from the contribution of their long-tailed nature. In addition, an individual’s predictability is correlated with the position of the individual in the static social network derived from the data. Individuals confined in a community—in the sense of an abundance of surrounding triangles—tend to have low predictability, and those bridging different communities tend to have high predictability.

  15. The conversational interface talking to smart devices

    CERN Document Server

    McTear, Michael; Griol, David

    2016-01-01

    This book provides a comprehensive introduction to the conversational interface, which is becoming the main mode of interaction with virtual personal assistants, smart devices, various types of wearables, and social robots. The book consists of four parts: Part I presents the background to conversational interfaces, examining past and present work on spoken language interaction with computers; Part II covers the various technologies that are required to build a conversational interface along with practical chapters and exercises using open source tools; Part III looks at interactions with smart devices, wearables, and robots, and then goes on to discusses the role of emotion and personality in the conversational interface; Part IV examines methods for evaluating conversational interfaces and discusses future directions. · Presents a comprehensive overview of the various technologies that underlie conversational user interfaces; · Combines descriptions of conversational user interface technologies with a gui...

  16. Technological progress and challenges towards cGMP manufacturing of human pluripotent stem cells based therapeutic products for allogeneic and autologous cell therapies.

    Science.gov (United States)

    Abbasalizadeh, Saeed; Baharvand, Hossein

    2013-12-01

    Recent technological advances in the generation, characterization, and bioprocessing of human pluripotent stem cells (hPSCs) have created new hope for their use as a source for production of cell-based therapeutic products. To date, a few clinical trials that have used therapeutic cells derived from hESCs have been approved by the Food and Drug Administration (FDA), but numerous new hPSC-based cell therapy products are under various stages of development in cell therapy-specialized companies and their future market is estimated to be very promising. However, the multitude of critical challenges regarding different aspects of hPSC-based therapeutic product manufacturing and their therapies have made progress for the introduction of new products and clinical applications very slow. These challenges include scientific, technological, clinical, policy, and financial aspects. The technological aspects of manufacturing hPSC-based therapeutic products for allogeneic and autologous cell therapies according to good manufacturing practice (cGMP) quality requirements is one of the most important challenging and emerging topics in the development of new hPSCs for clinical use. In this review, we describe main critical challenges and highlight a series of technological advances in all aspects of hPSC-based therapeutic product manufacturing including clinical grade cell line development, large-scale banking, upstream processing, downstream processing, and quality assessment of final cell therapeutic products that have brought hPSCs closer to clinical application and commercial cGMP manufacturing. © 2013.

  17. Leadership is a conversation.

    Science.gov (United States)

    Groysberg, Boris; Slind, Michael

    2012-06-01

    Globalization and new technologies have sharply reduced the efficacy of command-and-control management and its accompanying forms of corporate communication. In the course of a recent research project, the authors concluded that by talking with employees, rather than simply issuing orders, leaders can promote operational flexibility, employee engagement, and tight strategic alignment. Groysberg and Slind have identified four elements of organizational conversation that reflect the essential attributes of interpersonal conversation: intimacy, interactivity, inclusion, and intentionality. Intimacy shifts the focus from a top-down distribution of information to a bottom-up exchange of ideas. Organizational conversation is less corporate in tone and more casual. And it's less about issuing and taking orders than about asking and answering questions. Interactivity entails shunning the simplicity of monologue and embracing the unpredictable vitality of dialogue. Traditional one-way media-print and broadcast, in particular-give way to social media buttressed by social thinking. Inclusion turns employees into full-fledged conversation partners, entitling them to provide their own ideas, often on company channels. They can create content and act as brand ambassadors, thought leaders, and storytellers. Intentionality enables leaders and employees to derive strategically relevant action from the push and pull of discussion and debate.

  18. Patient-derived mesenchymal stem cells as delivery vehicles for oncolytic virotherapy: novel state-of-the-art technology

    Directory of Open Access Journals (Sweden)

    Ramírez M

    2015-10-01

    Full Text Available Manuel Ramírez,1 Javier García-Castro,2 Gustavo J Melen,1 África González-Murillo,1 Lidia Franco-Luzón1 1Oncohematología, Hospital Universitario Niño Jesús, 2Unidad de Biotecnología Celular, Instituto de Salud Carlos III, Madrid, Spain Abstract: Oncolytic virotherapy is gaining interest in the clinic as a new weapon against cancer. In vivo administration of oncolytic viruses showed important limitations that decrease their effectiveness very significantly: the antiviral immune response causes the elimination of the therapeutic effect, and the poor natural ability of oncolytic viruses to infect micrometastatic lesions significantly minimizes the effective dose of virus. This review will focus on updating the technical and scientific foundations of one of the strategies developed to overcome these limitations, ie, using cells as vehicles for oncolytic viruses. Among many candidates, a special type of adult stem cell, mesenchymal stem cells (MSCs, have already been used in the clinic as cell vehicles for oncolytic viruses, partly due to the fact that these cells are actively being evaluated for other indications. MSC carrier cells are used as Trojan horses loaded with oncoviruses, are administered systemically, and release their cargos at the right places. MSCs are equipped with an array of molecules involved in cell arrest in the capillaries (integrins and selectins, migration toward specific parenchymal locations within tissues (chemokine receptors, and invasion and degradation of the extracellular matrix (proteases. In addition to anatomical targeting capacity, MSCs have a well-recognized role in modulating immune responses by affecting cells of the innate (antigen-presenting cells, natural killer cells and adaptive immune system (effector and regulatory lymphocytes. Therefore, carrier MSCs may also modulate the immune responses taking place after therapy, ie, the antiviral and the antitumor immune responses. Keywords: virotherapy

  19. STEM Careers Are Out of This World--No Need to Fear Science, Technology, Engineering, or Math

    Science.gov (United States)

    Griffin, Amanda; Manning, Kelvin

    2012-01-01

    At NASA, we fully support the President's Educate to Innovate Program in the hopes that American students move from the middle of the pack to the top in the next decade; and that we are expanding STEM education and career opportunities for underrepresented groups, including minorities and females. The first goal we have implemented to help accomplish this is to Strengthen NASA and the Nation's future workforce - Many of you in the audience could be our potential workforce, and the co-op and intern program at NASA is helping students like you. The second goal is to Attract and retain students in STEM disciplines-To compete effectively for the minds, imaginations and career ambitions of young people like you, throughout NASA, we regularly send educators and NASA speakers into classrooms to work directly with you, encouraging you to follow in the footsteps of NASA engineers and scientists. The Third goal is to Engage Americans in NASA's mission- To get young people involved in NASA's mission, we have many exciting programs for college students like the Lunabotics Mining Competition and the Cubes Satellites sent to space

  20. Student Teachers of Technology and Design: Can Short Periods of STEM-Related Industrial Placement Change Student Perceptions of Engineering and Technology?

    Science.gov (United States)

    Gibson, Ken S.

    2012-01-01

    This is a report, on a small-scale case study, of a programme of short industrial placements (5 day block) for student teachers of technology and design in Northern Ireland. Such placements increase student awareness and understanding of the nature of Engineering and Technology and therefore better prepare them to teach these subjects, as integral…

  1. Fiscal 1996 achievement report. Development of liquid fuel conversion technology (Development for practical application of a new production process); 1996 nendo ekitai nenryo tenkan gijutsu kaihatsu seika hokokusho. Shinseizo process jitsuyoka kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The research and development aims to establish, through verification tests, practical application technologies for two methods, namely, a 'low-temperature liquid phase method' by which cost will be reduced thanks to simplified plant facilities and a 'vapor phase fluidized bed method' in which a composite reforming process may be combined for better economics of scale with a vapor phase fluidized methanol synthesizing method whose facilities may be built to be very large. For the former method, development efforts are made to enable catalyst performance characterization and low-temperature liquid phase methanol production using a small pyrolysis reactor. In the research on pyrolysis reaction, a Raney copper/KOMe/MeOH-based catalyst is used, and this attains a raw material gas conversion efficiency of 92.7%. In the construction of a low temperature liquid phase process, it is found that a single spun conversion efficiency of not less than 90% may be achieved using a heterogeneous catalyst. For the latter method, studies are conducted for the development of, and for the establishment of technologies for designing, synthetic gas production technologies in the development of a heat exchanger type composite reforming furnace and a fluidized bed methanol production process, the development of a catalyst manufacturing technology for fluidized bed practical application, the development of a fluidized bed methanol production technology, and the optimization of the process and its economic efficiency. (NEDO)

  2. Types of Stem Cells

    Science.gov (United States)

    ... Stem Cell Glossary Search Toggle Nav Types of Stem Cells Stem cells are the foundation from which all ... Learn About Stem Cells > Types of Stem Cells Stem cells Stem cells are the foundation for every organ ...

  3. A Study of the Experience of Female African-American Seventh Graders in a Science, Technology, Engineering, and Math (STEM) Afterschool Program

    Science.gov (United States)

    Hinds, Beverley Fiona

    The purpose of this qualitative study was to determine what inspires or leads seventh-grade African-American girls toward an interest in STEM, to characterize and describe the context of an out-of-school STEM learning environment, explore the impact on the seventh- grade African-American girls who participated in the program as it relates to individual STEM identity, and identify personal and academic experiences of seventh-grade African- American girls that contribute to the discouragement or pursuit of science and math-related academic pathways and careers. Notable findings in this study included the following: 1. Participants were interested in STEM and able to identify both external and internal influences that supported their involvement and interest in STEM activities. External influences expanded and elevated exposure to STEM experiences. 2. The MJS program provided an opportunity for participants to overcome challenges related to science and math knowledge and skills in school. 3. The MJS program increased levels of interest in STEM for the participants. 4. All participants increased their capacity to demonstrate increased knowledge in STEM content as a result of the learning experiences within the MJS program, and participants transferred this knowledge to experiences outside of the program including school. 5. The STEM learning environment provided multiple opportunities for participants to meet high expectation and access to engaging activities within a supportive, well-managed setting. 6. The MJS program participants demonstrated behaviors related to building a STEM identity through the components described by Carlone and Johnson (2007), including recognition-internal and external acknowledgement of being a STEM person; competence-demonstrating an understanding of STEM content; and performance-publically exhibiting STEM knowledge and skills. The findings in this study suggested that African-American seventh-grade girls interested in STEM are inspired

  4. Haematopoietic stem and progenitor cells from human pluripotent stem cells

    Science.gov (United States)

    Sugimura, Ryohichi; Jha, Deepak Kumar; Han, Areum; Soria-Valles, Clara; da Rocha, Edroaldo Lummertz; Lu, Yi-Fen; Goettel, Jeremy A.; Serrao, Erik; Rowe, R. Grant; Malleshaiah, Mohan; Wong, Irene; Sousa, Patricia; Zhu, Ted N.; Ditadi, Andrea; Keller, Gordon; Engelman, Alan N.; Snapper, Scott B.; Doulatov, Sergei; Daley, George Q.

    2018-01-01

    A variety of tissue lineages can be differentiated from pluripotent stem cells by mimicking embryonic development through stepwise exposure to morphogens, or by conversion of one differentiated cell type into another by enforced expression of master transcription factors. Here, to yield functional human haematopoietic stem cells, we perform morphogen-directed differentiation of human pluripotent stem cells into haemogenic endothelium followed by screening of 26 candidate haematopoietic stem-cell-specifying transcription factors for their capacity to promote multi-lineage haematopoietic engraftment in mouse hosts. We recover seven transcription factors (ERG, HOXA5, HOXA9, HOXA10, LCOR, RUNX1 and SPI1) that are sufficient to convert haemogenic endothelium into haematopoietic stem and progenitor cells that engraft myeloid, B and T cells in primary and secondary mouse recipients. Our combined approach of morphogen-driven differentiation and transcription-factor-mediated cell fate conversion produces haematopoietic stem and progenitor cells from pluripotent stem cells and holds promise for modelling haematopoietic disease in humanized mice and for therapeutic strategies in genetic blood disorders. PMID:28514439

  5. Multifaceted Interpretation of Colon Cancer Stem Cells.

    Science.gov (United States)

    Hatano, Yuichiro; Fukuda, Shinya; Hisamatsu, Kenji; Hirata, Akihiro; Hara, Akira; Tomita, Hiroyuki

    2017-07-05

    Colon cancer is one of the leading causes of cancer-related deaths worldwide, despite recent advances in clinical oncology. Accumulating evidence sheds light on the existence of cancer stem cells and their role in conferring therapeutic resistance. Cancer stem cells are a minor fraction of cancer cells, which enable tumor heterogeneity and initiate tumor formation. In addition, these cells are resistant to various cytotoxic factors. Therefore, elimination of cancer stem cells is difficult but essential to cure the malignant foci completely. Herein, we review the recent evidence for intestinal stem cells and colon cancer stem cells, methods to detect the tumor-initiating cells, and clinical significance of cancer stem cell markers. We also describe the emerging problems of cancer stem cell theory, including bidirectional conversion and intertumoral heterogeneity of stem cell phenotype.

  6. A Multi-Case Study of Student Interactions with Educational Robots and Impact on Science, Technology, Engineering, and Math (STEM) Learning and Attitudes

    Science.gov (United States)

    Holmquist, Stephanie Kaye

    2014-01-01

    The demand for STEM trained workers continues to increase not only in the United States, but globally. Reports have indicated that the United States is not doing a good job encouraging students to pursue STEM oriented degrees. In particular, it has become increasingly important to emphasize STEM connections at an early level in order to encourage…

  7. Stem cells

    NARCIS (Netherlands)

    Jukes, Jojanneke; Both, Sanne; Post, Janine; van Blitterswijk, Clemens; Karperien, Marcel; de Boer, Jan; van Blitterswijk, Clemens A.

    2008-01-01

    This chapter defines stem cells and their properties. It identifies the major differences between embryonic and adult stem cells. Stem cells can be defined by two properties: the ability to make identical copies of themselves and the ability to form other cell types of the body. These properties are

  8. Microbial Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, Merry [American Society for Microbiology (ASM), Washington, DC (United States); Wall, Judy D. [Univ. of Missouri, Columbia, MO (United States)

    2006-10-01

    The American Academy of Microbiology convened a colloquium March 10-12, 2006, in San Francisco, California, to discuss the production of energy fuels by microbial conversions. The status of research into various microbial energy technologies, the advantages and disadvantages of each of these approaches, research needs in the field, and education and training issues were examined, with the goal of identifying routes for producing biofuels that would both decrease the need for fossil fuels and reduce greenhouse gas emissions. Currently, the choices for providing energy are limited. Policy makers and the research community must begin to pursue a broader array of potential energy technologies. A diverse energy portfolio that includes an assortment of microbial energy choices will allow communities and consumers to select the best energy solution for their own particular needs. Funding agencies and governments alike need to prepare for future energy needs by investing both in the microbial energy technologies that work today and in the untested technologies that will serve the world’s needs tomorrow. More mature bioprocesses, such as ethanol production from starchy materials and methane from waste digestors, will find applications in the short term. However, innovative techniques for liquid fuel or biohydrogen production are among the longer term possibilities that should also be vigorously explored, starting now. Microorganisms can help meet human energy needs in any of a number of ways. In their most obvious role in energy conversion, microorganisms can generate fuels, including ethanol, hydrogen, methane, lipids, and butanol, which can be burned to produce energy. Alternatively, bacteria can be put to use in microbial fuel cells, where they carry out the direct conversion of biomass into electricity. Microorganisms may also be used some day to make oil and natural gas technologies more efficient by sequestering carbon or by assisting in the recovery of oil and

  9. Findings on the Development and Use of Technology-Infused Curricula in Preschool Classrooms. Interactive STEM Research Brief

    Science.gov (United States)

    Stiles, Jennifer; Louie, Jo

    2016-01-01

    Mobile tablets are becoming more prevalent in educational settings, but little is known about the impact of using technology-infused curricula in preschool classrooms. The research summarized in this brief suggests that well-designed tablet-based activities can indeed improve student learning outcomes at the preschool level. These positive…

  10. Examining Teacher Mental Models for the Implementation of a STEM-Focused Curriculum Paradigm in Engineering and Technology Education

    Science.gov (United States)

    Kerr, Janel M.

    2013-01-01

    The purpose of this study was to explore the role of mental models in Idaho's Engineering and Technology Education teachers' in decision making when faced with major curriculum changes. Senge (1990) defined mental models as, "deeply ingrained assumptions, generalizations, or even pictures or images that influence how we understand the world…

  11. Section 7033 of the America COMPETES Act: Hispanic-Serving Institutions and Science, Technology, Engineering and Mathematics (STEM)

    Science.gov (United States)

    Gartrell, Sandra

    2009-01-01

    On March 1, 2009 from 2 pm to 5 pm at the Madison Hotel in Washington, DC, the National Science Foundation hosted a listening session, requesting input on Section 7033 of the America COMPETES (Creating Opportunities to Meaningfully Promote Excellence in Technology, Education, and Science) Act regarding Hispanic-serving institutions and science,…

  12. Hydrogen photoproduction by photoelectrochemical conversion

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    The water-splitting reaction by photoelectrochemical processes has gained much more attention than any of many reactions proposed for solar generation of energy-rich molecules (fuels). The conversion efficiency of the photosystem is the key factor. The higher the efficiency, the more economically feasible will be the conversion scheme. The conversion efficiency is a function of the semiconductor properties, light intensity, spectral quality, properties of the electrolyte, counterelectrode, cell configuration, etc. The semiconductor parameters include band gap, absorption coefficient and diffusion length. The area and material used for a counterelectrode are important when considering polarization losses in a two-electrode system. Besides, the stability problem is also a very important one to meet the requirement for practical applications. This paper reviews some important issues on photoelectrochemical generation of hydrogen by water splitting. It includes energy conversion efficiency, market assessment and cost goal, state of the technology, and future directions for research

  13. Science Self-Efficacy and Innovative Behavior (IB) in Nigerian College Students Enrolled in Science, Technology, Engineering, and Mathematics (STEM) Programs

    Science.gov (United States)

    Okonkwo, Charles

    This study will explore how science self-efficacy among college students in science, technology, engineering, and mathematics (STEM) fields in Nigeria predicts their innovation. Several reports on African development argue that science, technology and innovation underpin targets for dramatically reducing poverty in its many dimensions---income poverty, hunger, disease, exclusion, lack of infrastructure and shelter---while promoting gender equality, education, health, and environmental sustainability (UN Millennium Project, 2005). If African countries in general, including Nigeria, are to move from the exploitation of natural resources to technological innovation as the foundation for development, stakeholders in these countries must encourage development of individual ability to innovate products, services and work processes in crucial organizations (DeJong & DenHartog, 2010). The common denominator in the scientific and technological development of any country or organization is the individuals that make up these entities. An individual's engagement is the foundation for group motivation, innovation and improvement. These ideas inform the purpose of this study: to investigate how science self-efficacy among college students in various engineering fields in Nigeria predicts self-reported innovative behavior (IB), also referred to as Innovative Work Behavior (IWB). IB involves initiating new and useful ideas, processes, products or procedures, as well as the process of implementing these ideas (Farr & Ford, 1990; Scott & Bruce, 1994). The general findings of this study align with the dictates of social cognitive theory. Specifically, research indicates self-efficacy has the most predictive power for performance when it is measured at a level specific to the expected task (Bandura, 1997; Pajares, 1996). The findings from the hierarchical multiple regressions confirm that individuals' perceived science efficacy plays an important role in their perceived self

  14. A Conversation with Adam Heller

    OpenAIRE

    Heller, A; Cairns, EJ

    2015-01-01

    © 2015 by Annual Reviews. All rights reserved. Adam Heller, Ernest Cockrell Sr. Chair in Engineering Emeritus of the John J. McKetta Department of Chemical Engineering at The University of Texas at Austin, recalls his childhood in the Holocaust and his contributions to science and technology that earned him the US National Medal of Technology and Innovation in a conversation with Elton J. Cairns, Professor of Chemical and Biomolecular Engineering at the University of California, Berkeley. Dr....

  15. Evolution of energy conversion plants

    International Nuclear Information System (INIS)

    Osnaghi, C.

    2001-01-01

    The paper concerns the evolution and the future development of energy conversion plants and puts into evidence the great importance of the scientific and technological improvement in machines design, in order to optimize the use of energy resources and to improve ambient compatibility [it

  16. Advancing STEM Education: A 2020 Vision

    Science.gov (United States)

    Bybee, Rodger W.

    2010-01-01

    STEM (an acronym for science, technology, engineering and mathematics) had its origins in the 1990s at the National Science Foundation (NSF) and has been used as a generic label for any event, policy, program, or practice that involves one or several of the STEM disciplines. However, a recent survey on the "perception of STEM" found that most…

  17. Enhancing the Psychology STEM Student Journey

    Science.gov (United States)

    Hill, Kimberley M.

    2017-01-01

    Psychology is a valuable Science, Technology, Engineering, and Mathematics (STEM) discipline, but one which could do far more at communicating its value to the wider public. This paper discusses how popular initiatives, such as "The University of Northampton's STEM Champions" programme, enhance psychology's STEM membership, while…

  18. Biomass Thermochemical Conversion Program: 1986 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Schiefelbein, G.F.; Stevens, D.J.; Gerber, M.A.

    1987-01-01

    Wood and crop residues constitute a vast majority of the biomass feedstocks available for conversion, and thermochemical processes are well suited for conversion of these materials. Thermochemical conversion processes can generate a variety of products such as gasoline hydrocarbon fuels, natural gas substitutes, or heat energy for electric power generation. The US Department of Energy is sponsoring research on biomass conversion technologies through its Biomass Thermochemical Conversion Program. Pacific Northwest Laboratory has been designated the Technical Field Management Office for the Biomass Thermochemical Conversion Program with overall responsibility for the Program. This report briefly describes the Thermochemical Conversion Program structure and summarizes the activities and major accomplishments during fiscal year 1986. 88 refs., 31 figs., 5 tabs.

  19. "Excellence" in STEM Education

    Science.gov (United States)

    Clark, Aaron C.

    2012-01-01

    So what does it take to achieve excellence in STEM education? That is the title of the author's presentation delivered at International Technology and Engineering Educators Association's (ITEEA's) FTEE "Spirit of Excellence" Breakfast on March 16, 2012, in Long Beach, California. In preparation for this presentation, the author went back and read…

  20. Frequency conversion of structured light.

    Science.gov (United States)

    Steinlechner, Fabian; Hermosa, Nathaniel; Pruneri, Valerio; Torres, Juan P

    2016-02-15

    Coherent frequency conversion of structured light, i.e. the ability to manipulate the carrier frequency of a wave front without distorting its spatial phase and intensity profile, provides the opportunity for numerous novel applications in photonic technology and fundamental science. In particular, frequency conversion of spatial modes carrying orbital angular momentum can be exploited in sub-wavelength resolution nano-optics and coherent imaging at a wavelength different from that used to illuminate an object. Moreover, coherent frequency conversion will be crucial for interfacing information stored in the high-dimensional spatial structure of single and entangled photons with various constituents of quantum networks. In this work, we demonstrate frequency conversion of structured light from the near infrared (803 nm) to the visible (527 nm). The conversion scheme is based on sum-frequency generation in a periodically poled lithium niobate crystal pumped with a 1540-nm Gaussian beam. We observe frequency-converted fields that exhibit a high degree of similarity with the input field and verify the coherence of the frequency-conversion process via mode projection measurements with a phase mask and a single-mode fiber. Our results demonstrate the suitability of exploiting the technique for applications in quantum information processing and coherent imaging.

  1. Bioprinting for stem cell research

    Science.gov (United States)

    Tasoglu, Savas; Demirci, Utkan

    2012-01-01

    Recently, there has been a growing interest to apply bioprinting techniques to stem cell research. Several bioprinting methods have been developed utilizing acoustics, piezoelectricity, and lasers to deposit living cells onto receiving substrates. Using these technologies, spatially defined gradients of immobilized proteins can be engineered to direct stem cell differentiation into multiple subpopulations of different lineages. Stem cells can also be patterned in a high-throughput manner onto flexible implementation patches for tissue regeneration or onto substrates with the goal of accessing encapsulated stem cell of interest for genomic analysis. Here, we review recent achievements with bioprinting technologies in stem cell research, and identify future challenges and potential applications including tissue engineering and regenerative medicine, wound healing, and genomics. PMID:23260439

  2. An Online Student Research Institute Designed to Engage Students in Original Scientific Research Using State of the Art Technologies to Increase Participation in STEM Fields

    Science.gov (United States)

    Freed, R.

    2015-12-01

    Affordable and accessible technology has advanced tremendously in the last decade allowing educational paradigms to change dramatically to more student-centered, experiential and project-based models. Additionally, as the need to increase the number of students entering STEM fields in the United States becomes more critical it is imperative to understand the factors that determine student career pathways and to provide opportunities for students to experience, understand and pursue scientific endeavors. The Institute for Student Astronomical Research was founded in order to provide a means for high school and early undergraduate students to engage in meaningful and relevant scientific research. A major goal is to give students the experience of true-to-life scientific investigation from the planning and proposal stages to the data collection and analysis, writing up and presenting of scientific findings and finally to the publication of results. Furthermore, the Institute is designed to collect data on how involvement in the Science Research Seminars influences educational and career choices for students in longitudinal studies following participants for several years. In the first year of the online course of the Institute 10 student teams conducted original research and published their findings in peer-reviewed journals. Lessons learned from the pilot year are being applied to the Institute as efforts to scale up the program are underway.

  3. Engaging learners in STEM education

    Directory of Open Access Journals (Sweden)

    Joseph Krajcik

    2017-04-01

    Full Text Available In this manuscript we focus on how to develop STEM learning environments, and how STEM can be implemented in K-12 schools. We focus on the following question: “How can we support students in building a deep, integrated knowledge of STEM so that they have the practical knowledge and problem solving skills necessary to live in and improve the world?” We also discuss criteria for evaluating STEM learning environments and the challenges teachers face in implementing STEM. We define STEM as the integration of science, engineering, technology, and mathematics to focus on solving pressing individual and societal problems. Engaging students in STEM also means engaging learners in the design process. Design is integral to student thinking in the STEM world. The design process is very non-linear and iterative in its nature but requires clearly articulating and identifying the design problem, researching what is known about the problem, generating potential solutions, developing prototype designs (artifacts that demonstrate solutions, and sharing and receiving feedback. With the integration of design, STEM education has the potential to support students in learning big ideas in science and engineering, as well as important scientific and engineering practices, and support students in developing important motivational outcomes such as ownership, agency and efficacy. Moreover, students who engage in STEM learning environments will also develop 21st century capabilities such as problem solving, communication, and collaboration skills.

  4. NASA Earth Systems, Technology and Energy Education for Minority University and Research Education Program Promotes Climate Literacy by Engaging Students at Minority Serving Institutions in STEM

    Science.gov (United States)

    Murray, B.; Alston, E. J.; Chambers, L. H.; Bynum, A.; Montgomery, C.; Blue, S.; Kowalczak, C.; Leighton, A.; Bosman, L.

    2017-12-01

    NASA Earth Systems, Technology and Energy Education for Minority University Research & Education Program - MUREP (ESTEEM) activities enhance institutional capacity of minority serving institutions (MSIs) related to Earth System Science, Technology and energy education; in turn, increasing access of underrepresented groups to science careers and opportunities. ESTEEM is a competitive portfolio that has been providing funding to institutions across the United States for 10 years. Over that time 76 separate activities have been funded. Beginning in 2011 ESTEEM awards focused on MSIs and public-school districts with high under-represented enrollment. Today ESTEEM awards focus on American Indian/Alaska Native serving institutions (Tribal Colleges and Universities), the very communities most severely in need of ability to deal with climate adaptation and resiliency. ESTEEM engages a multi-faceted approach to address economic and cultural challenges facing MSI communities. PIs (Principal Investigators) receive support from a management team at NASA, and are supported by a larger network, the ESTEEM Cohort, which connects regularly through video calls, virtual video series and in-person meetings. The cohort acts as a collective unit to foster interconnectivity and knowledge sharing in both physical and virtual settings. ESTEEM partners with NASA's Digital Learning Network (DLNTM) in a unique non-traditional model to leverage technical expertise. DLN services over 10,000 participants each year through interactive web-based synchronous and asynchronous events. These events allow for cost effective (no travel) engagement of multiple, geographically dispersed audiences to share local experiences with one another. Events allow PIs to grow their networks, technical base, professional connections, and develop a sense of community, encouraging expansion into larger and broader interactions. Over 256 connections, beyond the 76 individual members, exist within the cohort. PIs report

  5. The Effect of STEM Learning through the Project of Designing Boat Model toward Student STEM Literacy

    Science.gov (United States)

    Tati, T.; Firman, H.; Riandi, R.

    2017-09-01

    STEM Learning focusses on development of STEM-literate society, the research about implementation of STEM learning to develope students’ STEM literacy is still limited. This study is aimed to examine the effect of implementation STEM learning through the project of designing boat model on students STEM literacy in energy topic. The method of this study was a quasi-experiment with non-randomized pretest-posttest control group design. There were two classes involved, the experiment class used Project Based Learning with STEM approach and control class used Project-Based Learning without STEM approach. A STEM Literacy test instrument was developed to measure students STEM literacy which consists of science literacy, mathematics literacy, and technology-engineering literacy. The analysis showed that there were significant differences on improvement science literacy, mathematics technology-engineering between experiment class and control class with effect size more than 0.8 (large effect). The difference of improvement of STEM literacy between experiment class and control class is caused by the existence of design engineering activity which required students to apply the knowledge from every field of STEM. The challenge that was faced in STEM learning through design engineering activity was how to give the students practice to integrate STEM field in solving the problems. In additional, most of the students gave positive response toward implementation of STEM learning through design boat model project.

  6. Communal biomass conversion plants

    International Nuclear Information System (INIS)

    1991-06-01

    The Coordinating Committee set up by the Danish government in 1986 were given the responsibility of investigating the potentials for biomass conversion plants in Denmark, especially in relation to agricultural, environmental and energy aspects. The results of the Committee's plan of management for this project are presented. This main report covers 13 background reports which deal with special aspects in detail. The report describes the overall plan of management, the demonstration and follow-up programme and the individual biogas demonstration plants. Information gained from these investigations is presented. The current general status, (with emphasis on the technical and economical aspects) and the prospects for the future are discussed. The interest other countries have shown in Danish activities within the field of biogas production is described, and the possibilities for Danish export of technology and know-how in this relation are discussed. It is claimed that Denmark is the first country that has instigated a coordinated development programme for biomass conversion plants. (AB) 24 refs

  7. Solar spectrum conversion for photovoltaics using nanoparticles

    NARCIS (Netherlands)

    Sark, W.G.J.H.M. van; Meijerink, A.; Schropp, R.E.I.

    2012-01-01

    The possibility to tune chemical and physical properties in nanosized materials has a strong impact on a variety of technologies, including photovoltaics. One of the prominent research areas of nanomaterials for photovoltaics involves spectral conversion. Conventional single-junction

  8. International conference on military conversion and science. Utilization/disposal of the excess fissile weapon materials: scientific, technological and socio-economic aspects

    International Nuclear Information System (INIS)

    Kouzminov, V.; Martellini, M.

    1996-01-01

    The Proceedings of the Conference includes the papers presented by the eminent specialists in the field of utilisation and/or disposal of excess fissile materials, each with a separate abstract, as well as the Conference opening and introduction speeches. According to the concerned subjects presentations were divided into following five sessions: perspectives of nuclear research and development; Technical problems and possibilities of civilian utilization of Highly enriched uranium (HEU) and plutonium including alternate strategies (application of MOX fuel) and operational and safety problems; Comparison of different options for weapon-grade Pu utilization connected to present programme for recycling of civilian Pu; Socio-economic aspects including cost of Pu conversion and fabrication of MOX fuel; Effects of different strategies of waste disposal including environmental and safety related issues

  9. Conversational Agents in E-Learning

    Science.gov (United States)

    Kerry, Alice; Ellis, Richard; Bull, Susan

    This paper discusses the use of natural language or 'conversational' agents in e-learning environments. We describe and contrast the various applications of conversational agent technology represented in the e-learning literature, including tutors, learning companions, language practice and systems to encourage reflection. We offer two more detailed examples of conversational agents, one which provides learning support, and the other support for self-assessment. Issues and challenges for developers of conversational agent systems for e-learning are identified and discussed.

  10. Environmental effects of energy conversion

    International Nuclear Information System (INIS)

    Hansmeyer, K.H.; Fortak, H.; Knoepp, H.; Lindackers, K.H.; Schafhausen, F.; Schoedel, J.P.

    1984-01-01

    The article presents an analysis of energy conversion systems by the ''Council of Environmental Experts'' in order to correct the erroneous assumption that small energy conversion systems will also be small-scale and negligible emitters of pollutants. The additional pollution caused by Neurath power plant is considered to be low, at least in its immediate vicinity, owing to the implementation of the most recent technical developments. The environmental effects of energy conversion processes are discussed, including the waste heat problem and processes for water-cooling of power plants. General aspects of a new concept of energy taxation are discussed which is to reduce energy consumption. The problem of radioactive waste is discussed from spent fuel storage and reprocessing to the decommissioning of older power plants. The author points out that also new fossil-fuel technologies will pollute the environment. (orig.) [de

  11. The 3R anthracite clean coal technology: Economical conversion of brown coal to anthracite type clean coal by low temperature carbonization pre-treatment process

    Directory of Open Access Journals (Sweden)

    Someus Edward

    2006-01-01

    Full Text Available The preventive pre-treatment of low grade solid fuels is safer, faster, better, and less costly vs. the "end-of-the-pipe" post treatment solutions. The "3R" (Recycle-Reduce-Reuse integrated environment control technology provides preventive pre-treatment of low grade solid fuels, such as brown coal and contaminated solid fuels to achieve high grade cleansed fuels with anthracite and coke comparable quality. The goal of the 3R technology is to provide cost efficient and environmentally sustainable solutions by preventive pre-treatment means for extended operations of the solid fuel combustion power plants with capacity up to 300 MWe power capacities. The 3R Anthracite Clean Coal end product and technology may advantageously be integrated to the oxyfuel-oxy-firing, Foster Wheeler anthracite arc-fired utility type boiler and Heat Pipe Reformer technologies in combination with CO2 capture and storage programs. The 3R technology is patented original solution. Advantages. Feedstock flexibility: application of pre-treated multi fuels from wider fuel selection and availability. Improved burning efficiency. Technology flexibility: efficient and advantageous inter-link to proven boiler technologies, such as oxyfuel and arcfired boilers. Near zero pollutants for hazardous-air-pollutants: preventive separation of halogens and heavy metals into small volume streams prior utilization of cleansed fuels. >97% organic sulphur removal achieved by the 3R thermal pre-treatment process. Integrated carbon capture and storage (CCS programs: the introduction of monolitic GHG gas is improving storage safety. The 3R technology offers significant improvements for the GHG CCS conditions. Cost reduction: decrease of overall production costs when all real costs are calculated. Improved safety: application of preventive measures. For pre-treatment a specific purpose designed, developed, and patented pyrolysis technology used, consisting of a horizontally arranged externally

  12. Coal conversion processes and analysis methodologies for synthetic fuels production. [technology assessment and economic analysis of reactor design for coal gasification

    Science.gov (United States)

    1979-01-01

    Information to identify viable coal gasification and utilization technologies is presented. Analysis capabilities required to support design and implementation of coal based synthetic fuels complexes are identified. The potential market in the Southeast United States for coal based synthetic fuels is investigated. A requirements analysis to identify the types of modeling and analysis capabilities required to conduct and monitor coal gasification project designs is discussed. Models and methodologies to satisfy these requirements are identified and evaluated, and recommendations are developed. Requirements for development of technology and data needed to improve gasification feasibility and economies are examined.

  13. Biomechanics of stem cells

    Science.gov (United States)

    Spector, A. A.; Yuan, D.; Somers, S.; Grayson, W. L.

    2018-04-01

    Stem cells play a key role in the healthy development and maintenance of organisms. They are also critically important in medical treatments of various diseases. It has been recently demonstrated that the mechanical factors such as forces, adhesion, stiffness, relaxation, etc. have significant effects on stem cell functions. Under physiological conditions, cells (stem cells) in muscles, heart, and blood vessels are under the action of externally applied strains. We consider the stem cell microenvironment and performance associated with their conversion (differentiation) into skeletal muscle cells. Two problems are studied by using mathematical models whose parameters are then optimized by fitting experiments. First, we present our analysis of the process of stem cell differentiation under the application of cyclic unidirectional strain. This process is interpreted as a transition through several (six) stages where each of them is defined in terms of expression of a set of factors typical to skeletal muscle cells. The stem cell evolution toward muscle cells is described by a system of nonlinear ODEs. The parameters of the model are determined by fitting the experimental data on the time course of expression of the factors under consideration. Second, we analyse the mechanical (relaxation) properties of a scaffold that serves as the microenvironment for stem cells differentiation into skeletal muscle cells. This scaffold (surrounded by a liquid solution) is composed of unidirectional fibers with pores between them. The relaxation properties of the scaffold are studied in an experiment where a long cylindrical specimen is loaded by the application of ramp displacement until the strain reaches a prescribed value. The magnitude of the corresponding load is recorded. The specimen is considered as transversely isotropic poroelastic cylinder whose force relaxation is associated with liquid diffusion through the pores. An analytical solution for the total force applied to

  14. Learn About Stem Cells

    Science.gov (United States)

    ... Patient Handbook Stem Cell Glossary Search Toggle Nav Stem Cell Basics Stem cells are the foundation from which ... original cell’s DNA, cytoplasm and cell membrane. About stem cells Stem cells are the foundation of development in ...

  15. Increasing College Students' Interest and Engagement in STEM: A Comparison of Strategies for Challenging STEM Stereotypes

    Science.gov (United States)

    Shin, Jiyun Elizabeth L.

    2016-01-01

    Increasing science, technology, engineering, and mathematics (STEM) graduates has become an important part of the education agenda in the U.S. in recent years. Stereotypes about STEM (i.e., belief that STEM abilities are innate, and that European American men are best suited for STEM) have been identified as one of the critical factors that may…

  16. Students' Attitude towards STEM Education

    Science.gov (United States)

    Popa, Roxana-Alexandra; Ciascai, Liliana

    2017-01-01

    STEM is the acronym of Science, Technology, Engineering, and Mathematics fields. STEM education refers both to teaching and learning in the above-mentioned disciplines, but especially to teaching and learning a new discipline based on the integration of Science, Technology, Engineering, and Mathematics. The present survey aims to investigate the…

  17. Confronting Color-Blind STEM Talent Development: Toward a Contextual Model for Black Student STEM Identity

    Science.gov (United States)

    Collins, Kristina Henry

    2018-01-01

    What is Black student's science, technology, engineering, and mathematics (STEM) identity? The author addresses this question through a synthesis of the literature that includes studies that explore Black student identity. Background information regarding STEM achievement and persistence followed by empirical studies that explore STEM attitudes…

  18. Expanding educational access and opportunities: The globalization and foreign direct investment of multinational corporations and their influence on STEM, project-based learning and the national science and technology fair in schools in Costa Rica

    Science.gov (United States)

    Valdez, Joaquin G.

    The purpose of this qualitative study was to examine the influence of globalization and the foreign direct investment (FDI) of multinational corporations (MNCs) on the curriculum in schools in Costa Rica. The study focused primarily on Science, Technology, Engineering and Mathematics (STEM), Project-Based Learning (PBL), 21st century skills, and the national science and technology fair. The high influx of MNCs such as Intel has changed the global and educational culture of the country increasing the number of knowledge-based workers in Costa Rica. As a result, policy changes have been instituted in education to mirror the demands of sustaining the country's global economy. This study was supported by the creation of three research questions that would attempt to answer 1) the extent that teachers implementing STEM curriculum trace their practices back to policy, globalization, and multinational corporations as well as the extent to which the economic growth of Costa Rica and STEM education are related, 2) how mandating the national science and technology fair has influenced 21st century skills through project-based learning and the use of technology by teachers and its impact on curriculum and instruction, and 3) how has the national science and technology fair policy changed the value of STEM education for students, teachers, and educational leaders. To further understand the outcome of this study, four theoretical frameworks were applied that included, Spring's theory of world educational culture, Friedman's world flatteners, Wagner's 21st century skills and partnerships for 21st century skills, and Slough and Milam's STEM project-based learning theoretical framework. Each framework was applied to support the changes to the educational system; survival skills necessary to compete in the global job market; application of 21st century skills in the classroom and in the science projects students created. A research team comprised of 14 doctoral students, led by Dr

  19. Rapid determination of eight bioactive alkaloids in Portulaca oleracea L. by the optimal microwave extraction combined with positive-negative conversion multiple reaction monitor (+/-MRM) technology.

    Science.gov (United States)

    Liang, Xiao; Tian, Jinlong; Li, Lingzhi; Gao, Jun; Zhang, Qingyi; Gao, Pinyi; Song, Shaojiang

    2014-03-01

    A rapid and reliable microwave extraction and the triple quadrupole-linear ion trap mass spectrometry method was developed and validated for the determination of eight alkaloids in Portulaca oleracea L. The optimal microwave extraction (MWE) condition was performed at 60 °C for 12 min with ethanol-water (70:30, v/v) as the extracting solvent, and the solvent to solid ratio was 30:1. The alkaloids were first detected simultaneously by electrospray ionization tandem mass spectrometry under positive-negative conversion multiple reaction monitor ((+/-)MRM) technique. With investigating three different columns, samples were separated in only 8 min on a Waters ACQUITY UPLC HSS T3 (50 × 2.1 mm(2), 1.8 μm) column using acetonitrile and formic acid-water solution as a mobile phase with a flow rate at 0.2 mL/min. All calibration curves showed good linearity (r>0.999) within the test ranges. The method developed was validated with acceptable sensitivity, intra- and inter-day precision, reproducibility, and extraction recoveries. It was successfully applied to the determination of eight alkaloids in Portulaca oleracea L. from different sources and different harvest periods. The method also provide a reference for extraction and determination of alkaloids in other complex systems. © 2013 Elsevier B.V. All rights reserved.

  20. Overview of fuel conversion

    International Nuclear Information System (INIS)

    Green, A.E.S.

    1991-01-01

    The conversion of solid fuels to cleaner-burning and more user-friendly solid liquid or gaseous fuels spans many technologies. In this paper, the authors consider coal, residual oil, oil shale, tar sends tires, municipal oil waste and biomass as feedstocks and examine the processes which can be used in the production of synthetic fuels for the transportation sector. The products of mechanical processing to potentially usable fuels include coal slurries, micronized coal, solvent refined coal, vegetable oil and powdered biomall. The thermochemical and biochemical processes considered include high temperature carbide production, liquefaction, gasification, pyrolysis, hydrolysis-fermentation and anaerobic digestion. The products include syngas, synthetic natural gas, methanol, ethanol and other hydrocarbon oxygenates synthetic gasoline and diesel and jet engine oils. The authors discuss technical and economic aspects of synthetic fuel production giving particular attention and literature references to technologies not discussed in the five chapters which follow. Finally the authors discuss economic energy, and environmental aspects of synthetic fuels and their relationship to the price of imported oil

  1. Special issue: Plasma Conversion

    NARCIS (Netherlands)

    Nozaki, T.; Bogaerts, A.; Tu, X.; van de Sanden, M. C. M.

    2017-01-01

    With growing concern of energy and environmental issues, the combination of plasma and heterogeneous catalysts receives special attention in greenhouse gas conversion, nitrogen fixation and hydrocarbon chemistry. Plasma gas conversion driven by renewable electricity is particularly important for the

  2. The National Conversion Pilot Project

    International Nuclear Information System (INIS)

    Roberts, A.V.

    1995-01-01

    The National Conversion Pilot Project (NCPP) is a recycling project under way at the U.S. Department of Energy (DOE) Rocky Flats Environmental Technology Site (RFETS) in Colorado. The recycling aim of the project is threefold: to reuse existing nuclear weapon component production facilities for the production of commercially marketable products, to reuse existing material (uranium, beryllium, and radioactively contaminated scrap metals) for the production of these products, and to reemploy former Rocky Flats workers in this process

  3. Generation of a human induced pluripotent stem cell line from urinary cells of a patient with primary congenital glaucoma using integration free Sendai technology.

    Science.gov (United States)

    Zhang, Jingxue; Wu, Shen; Hu, Man; Liu, Qian

    2018-04-09

    We have generated a human induced pluripotent stem cell (iPSC) line derived from urinary cells of a 10years old patient with primary congenital glaucoma (PCG). The cells were reprogrammed with the human OSKM transcription factors using the Sendai-virus delivery system and shown to have full differentiation potential. The line is available and registered in the human pluripotent stem cell registry as BIOi001-A. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  4. STEM Education

    Science.gov (United States)

    & Development (LDRD) National Security Education Center (NSEC) Office of Science Programs Richard P Databases National Security Education Center (NSEC) Center for Nonlinear Studies Engineering Institute Scholarships STEM Education Programs Teachers (K-12) Students (K-12) Higher Education Regional Education

  5. A Model for Conversation

    DEFF Research Database (Denmark)

    Ayres, Phil

    2012-01-01

    This essay discusses models. It examines what models are, the roles models perform and suggests various intentions that underlie their construction and use. It discusses how models act as a conversational partner, and how they support various forms of conversation within the conversational activity...

  6. Direct Conversion of Energy.

    Science.gov (United States)

    Corliss, William R.

    This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. Direct energy conversion involves energy transformation without moving parts. The concepts of direct and dynamic energy conversion plus the laws governing energy conversion are investigated. Among the topics…

  7. Pluripotent stem cell-derived neural stem cells: From basic research to applications

    OpenAIRE

    Otsu, Masahiro; Nakayama, Takashi; Inoue, Nobuo

    2014-01-01

    Basic research on pluripotent stem cells is designed to enhance understanding of embryogenesis, whereas applied research is designed to develop novel therapies and prevent diseases. Attainment of these goals has been enhanced by the establishment of embryonic stem cell lines, the technological development of genomic reprogramming to generate induced-pluripotent stem cells, and improvements in vitro techniques to manipulate stem cells. This review summarizes the techniques required to generate...

  8. STEM crisis or STEM surplus? Yes and yes.

    Science.gov (United States)

    Xue, Yi; Larson, Richard C

    2015-05-01

    The last decade has seen considerable concern regarding a shortage of science, technology, engineering, and mathematics (STEM) workers to meet the demands of the labor market. At the same time, many experts have presented evidence of a STEM worker surplus. A comprehensive literature review, in conjunction with employment statistics, newspaper articles, and our own interviews with company recruiters, reveals a significant heterogeneity in the STEM labor market: the academic sector is generally oversupplied, while the government sector and private industry have shortages in specific areas.

  9. Elements of energy conversion

    CERN Document Server

    Russell, Charles R

    2013-01-01

    Elements of Energy Conversion brings together scattered information on the subject of energy conversion and presents it in terms of the fundamental thermodynamics that apply to energy conversion by any process. Emphasis is given to the development of the theory of heat engines because these are and will remain most important power sources. Descriptive material is then presented to provide elementary information on all important energy conversion devices. The book contains 10 chapters and opens with a discussion of forms of energy, energy sources and storage, and energy conversion. This is foll

  10. Iterated multidimensional wave conversion

    International Nuclear Information System (INIS)

    Brizard, A. J.; Tracy, E. R.; Johnston, D.; Kaufman, A. N.; Richardson, A. S.; Zobin, N.

    2011-01-01

    Mode conversion can occur repeatedly in a two-dimensional cavity (e.g., the poloidal cross section of an axisymmetric tokamak). We report on two novel concepts that allow for a complete and global visualization of the ray evolution under iterated conversions. First, iterated conversion is discussed in terms of ray-induced maps from the two-dimensional conversion surface to itself (which can be visualized in terms of three-dimensional rooms). Second, the two-dimensional conversion surface is shown to possess a symplectic structure derived from Dirac constraints associated with the two dispersion surfaces of the interacting waves.

  11. Land usage attributed to corn ethanol production in the United States: sensitivity to technological advances in corn grain yield, ethanol conversion, and co-product utilization.

    Science.gov (United States)

    Mumm, Rita H; Goldsmith, Peter D; Rausch, Kent D; Stein, Hans H

    2014-01-01

    Although the system for producing yellow corn grain is well established in the US, its role among other biofeedstock alternatives to petroleum-based energy sources has to be balanced with its predominant purpose for food and feed as well as economics, land use, and environmental stewardship. We model land usage attributed to corn ethanol production in the US to evaluate the effects of anticipated technological change in corn grain production, ethanol processing, and livestock feeding through a multi-disciplinary approach. Seven scenarios are evaluated: four considering the impact of technological advances on corn grain production, two focused on improved efficiencies in ethanol processing, and one reflecting greater use of ethanol co-products (that is, distillers dried grains with solubles) in diets for dairy cattle, pigs, and poultry. For each scenario, land area attributed to corn ethanol production is estimated for three time horizons: 2011 (current), the time period at which the 15 billion gallon cap for corn ethanol as per the Renewable Fuel Standard is achieved, and 2026 (15 years out). Although 40.5% of corn grain was channeled to ethanol processing in 2011, only 25% of US corn acreage was attributable to ethanol when accounting for feed co-product utilization. By 2026, land area attributed to corn ethanol production is reduced to 11% to 19% depending on the corn grain yield level associated with the four corn production scenarios, considering oil replacement associated with the soybean meal substituted in livestock diets with distillers dried grains with solubles. Efficiencies in ethanol processing, although producing more ethanol per bushel of processed corn, result in less co-products and therefore less offset of corn acreage. Shifting the use of distillers dried grains with solubles in feed to dairy cattle, pigs, and poultry substantially reduces land area attributed to corn ethanol production. However, because distillers dried grains with solubles

  12. Adolescent Girls’ STEM Identity Formation and Media Images of STEM Professionals: Considering the Influence of Contextual Cues

    Science.gov (United States)

    Steinke, Jocelyn

    2017-01-01

    Popular media have played a crucial role in the construction, representation, reproduction, and transmission of stereotypes of science, technology, engineering, and mathematics (STEM) professionals, yet little is known about how these stereotypes influence STEM identity formation. Media images of STEM professionals may be important sources of information about STEM and may be particularly salient and relevant for girls during adolescence as they actively consider future personal and professional identities. This article describes gender-stereotyped media images of STEM professionals and examines theories to identify variables that explain the potential influence of these images on STEM identity formation. Understanding these variables is important for expanding current conceptual frameworks of science/STEM identity to better determine how and when cues in the broader sociocultural context may affect adolescent girls’ STEM identity. This article emphasizes the importance of focusing on STEM identity relevant variables and STEM identity status to explain individual differences in STEM identity formation. PMID:28603505

  13. Adolescent Girls' STEM Identity Formation and Media Images of STEM Professionals: Considering the Influence of Contextual Cues.

    Science.gov (United States)

    Steinke, Jocelyn

    2017-01-01

    Popular media have played a crucial role in the construction, representation, reproduction, and transmission of stereotypes of science, technology, engineering, and mathematics (STEM) professionals, yet little is known about how these stereotypes influence STEM identity formation. Media images of STEM professionals may be important sources of information about STEM and may be particularly salient and relevant for girls during adolescence as they actively consider future personal and professional identities. This article describes gender-stereotyped media images of STEM professionals and examines theories to identify variables that explain the potential influence of these images on STEM identity formation. Understanding these variables is important for expanding current conceptual frameworks of science/STEM identity to better determine how and when cues in the broader sociocultural context may affect adolescent girls' STEM identity. This article emphasizes the importance of focusing on STEM identity relevant variables and STEM identity status to explain individual differences in STEM identity formation.

  14. A Microfabricated Segmented-Involute-Foil Regenerator for Enhancing Reliability and Performance of Stirling Engines. Phase III Final Report for the Radioisotope Power Conversion Technology NRA

    Science.gov (United States)

    Ibrahim, Mounir B.; Gedeon, David; Wood, Gary; McLean, Jeffrey

    2009-01-01

    Under Phase III of NASA Research Announcement contract NAS3-03124, a prototype nickel segmented-involute-foil regenerator was microfabricated and tested in a Sunpower Frequency-Test-Bed (FTB) Stirling convertor. The team for this effort consisted of Cleveland State University, Gedeon Associates, Sunpower Inc. and International Mezzo Technologies. Testing in the FTB convertor produced about the same efficiency as testing with the original random-fiber regenerator. But the high thermal conductivity of the prototype nickel regenerator was responsible for a significant performance degradation. An efficiency improvement (by a 1.04 factor, according to computer predictions) could have been achieved if the regenerator was made from a low-conductivity material. Also, the FTB convertor was not reoptimized to take full advantage of the microfabricated regenerator s low flow resistance; thus, the efficiency would likely have been even higher had the FTB been completely reoptimized. This report discusses the regenerator microfabrication process, testing of the regenerator in the Stirling FTB convertor, and the supporting analysis. Results of the pre-test computational fluid dynamics (CFD) modeling of the effects of the regenerator-test-configuration diffusers (located at each end of the regenerator) are included. The report also includes recommendations for further development of involute-foil regenerators from a higher-temperature material than nickel.

  15. Extensible Adaptive System for STEM Learning

    Science.gov (United States)

    2013-07-16

    Copyright 2013 Raytheon BBN Technologies Corp. All Rights Reserved ONR STEM Grand Challenge Extensible Adaptive System for STEM Learning ...Contract # N00014-12-C-0535 Raytheon BBN Technologies Corp. (BBN) Reference # 14217 In partial fulfillment of contract deliverable item # A001...Quarterly Progress Report #2 April 7, 2013 –July 6, 2013 Submitted July 16, 2013 BBN Technical POC: John Makhoul Raytheon BBN Technologies

  16. Functional Properties of Human Stem Cell-Derived Neurons in Health and Disease

    Directory of Open Access Journals (Sweden)

    Jason P. Weick

    2016-01-01

    Full Text Available Stem cell-derived neurons from various source materials present unique model systems to examine the fundamental properties of central nervous system (CNS development as well as the molecular underpinnings of disease phenotypes. In order to more accurately assess potential therapies for neurological disorders, multiple strategies have been employed in recent years to produce neuronal populations that accurately represent in vivo regional and transmitter phenotypes. These include new technologies such as direct conversion of somatic cell types into neurons and glia which may accelerate maturation and retain genetic hallmarks of aging. In addition, novel forms of genetic manipulations have brought human stem cells nearly on par with those of rodent with respect to gene targeting. For neurons of the CNS, the ultimate phenotypic characterization lies with their ability to recapitulate functional properties such as passive and active membrane characteristics, synaptic activity, and plasticity. These features critically depend on the coordinated expression and localization of hundreds of ion channels and receptors, as well as scaffolding and signaling molecules. In this review I will highlight the current state of knowledge regarding functional properties of human stem cell-derived neurons, with a primary focus on pluripotent stem cells. While significant advances have been made, critical hurdles must be overcome in order for this technology to support progression toward clinical applications.

  17. Stem Cell Basics

    Science.gov (United States)

    ... Tips Info Center Research Topics Federal Policy Glossary Stem Cell Information General Information Clinical Trials Funding Information Current ... Basics » Stem Cell Basics I. Back to top Stem Cell Basics I. Introduction: What are stem cells, and ...

  18. Stem and ICT education in intelligent environments

    CERN Document Server

    Kanematsu, Hideyuki

    2016-01-01

    This book combines information communication technology (ICT) with the creative interdisciplinary teaching approach known as STEM (science, technology, engineering, and mathematics). It introduces STEM and Creative Education and shows (through examples and creative activities) the importance and impact that ICT has for STEM and modern education.  The book describes the audio visual classroom, the use of the Internet, Social Networking and STEM, and provides STEM lessons for both the real and virtual worlds. Instructors will find this unique textbook to be very useful with students, of various ages, in creative education and engineering classes. This special book offers something for everyone. It serves as a guide for teachers in charge of science fairs and creative classes, especially those which require STEM education. It also includes activities to help develop creative thinking and problem-solving skills, and prepares students who plan to become teachers and mentors of the future. Readers in general can s...

  19. Stem Cells

    DEFF Research Database (Denmark)

    Sommerlund, Julie

    2004-01-01

    In his influential essay on markets, An essay on framing and overflowing (1998), Michel Callon writes that `the growing complexity of industrialized societies [is] due in large part to the movements of the technosciences, which are causing connections and interdependencies to proliferate'. This p...... and tantalizing than stem cells, in research, in medicine, or as products.......'. This paper is about tech-noscience, and about the proliferation of connections and interdependencies created by it.More specifically, the paper is about stem cells. Biotechnology in general has the power to capture the imagination. Within the field of biotechnology nothing seems more provocative...

  20. Stem cell facelift: between reality and fiction.

    Science.gov (United States)

    Atiyeh, Bishara S; Ibrahim, Amir E; Saad, Dibo A

    2013-03-01

    Stem cells are "big business" throughout medical technology, and their potential application in cosmetic procedures is no exception. One of the latest nonsurgical facial treatments (and new catchphrases) in plastic surgery is the "stem cell facelift." It is evident from the currently available scientific literature that the use of stem cell therapy for facial rejuvenation is limited to the theoretical induction of skin tightening and can in no way be equated to a facelift. In fact, what is advertised and promoted as a new and original technique of stem cell facelifting is mostly stem cell-enriched lipofilling. Despite encouraging data suggesting that adult stem cells hold promise for future applications, the data from clinical evidence available today do not substantiate the marketing and promotional claims being made to patients. To claim that the "stem cell facelift" is a complete facial rejuvenation procedure surgery is unethical.

  1. NASA-OAST program in photovoltaic energy conversion

    Science.gov (United States)

    Mullin, J. P.; Flood, D. J.

    1982-01-01

    The NASA program in photovoltaic energy conversion includes research and technology development efforts on solar cells, blankets, and arrays. The overall objectives are to increase conversion efficiency, reduce mass, reduce cost, and increase operating life. The potential growth of space power requirements in the future presents a major challenge to the current state of technology in space photovoltaic systems.

  2. Computers and conversation

    CERN Document Server

    Luff, Paul; Gilbert, Nigel G

    1986-01-01

    In the past few years a branch of sociology, conversation analysis, has begun to have a significant impact on the design of human*b1computer interaction (HCI). The investigation of human*b1human dialogue has emerged as a fruitful foundation for interactive system design.****This book includes eleven original chapters by leading researchers who are applying conversation analysis to HCI. The fundamentals of conversation analysis are outlined, a number of systems are described, and a critical view of their value for HCI is offered.****Computers and Conversation will be of interest to all concerne

  3. Analog-to-digital conversion

    CERN Document Server

    Pelgrom, Marcel

    2017-01-01

    This textbook is appropriate for use in graduate-level curricula in analog-to-digital conversion, as well as for practicing engineers in need of a state-of-the-art reference on data converters. It discusses various analog-to-digital conversion principles, including sampling, quantization, reference generation, nyquist architectures and sigma-delta modulation. This book presents an overview of the state of the art in this field and focuses on issues of optimizing accuracy and speed, while reducing the power level. This new, third edition emphasizes novel calibration concepts, the specific requirements of new systems, the consequences of 22-nm technology and the need for a more statistical approach to accuracy. Pedagogical enhancements to this edition include additional, new exercises, solved examples to introduce all key, new concepts and warnings, remarks and hints, from a practitioner’s perspective, wherever appropriate. Considerable background information and practical tips, from designing a PCB, to lay-o...

  4. IMAGE CONVERSION FOR LASER PYROGRAPHY

    Directory of Open Access Journals (Sweden)

    Adrian PETRU

    2015-12-01

    Full Text Available All previous studies of pyrography have been focussed on colour obtained through modifying the work parameters. This paper analyses colour nuances obtained by laser woodworking by measuring colour changes digitally. The investigated parameter is colour reproduction by laser technology, using different image conversion methods (Halftone Round, Jarvis, and so on. The changes of image reproduction are analysed globally and colour by colour. The results show that the colour nuances are represented to a more and less degree, according to the conversion method selected. To evaluate the aesthetic changes, CIEL*a*b* colour measurements were applied. The results show that laser burning on wood surfaces has a great influence on wood colour. These findings will be useful to develop innovative design possibilities for wood surfaces for furniture and other products.

  5. Progress in understanding conversion disorder

    Science.gov (United States)

    Allin, Matthew; Streeruwitz, Anna; Curtis, Vivienne

    2005-01-01

    Conversion disorder has a history that may reach back into antiquity, and it continues to present a clinical challenge to both psychiatrists and neurologists. This article reviews the current state of knowledge surrounding the prevalence, etiology, and neurobiology of conversion disorder. There have been improvements in the accuracy of diagnosis that are possibly related to improved technologies such as neuroimaging. Once the diagnosis is made, it is important to develop a therapeutic alliance between the patient and the medical team, and where comorbid psychiatric diagnoses have been made, these need to be adequately treated. While there have been no formal trials of medication or psychoanalytic treatments in this disorder, case reports suggest that a combination of antidepressants, psychotherapy, and a multidisciplinary approach to rehabilitation may be beneficial. PMID:18568070

  6. The Role of Non-Formal Contexts in Teacher Education for STEM: The Case of Horno[superscript 3] Science and Technology Interactive Centre

    Science.gov (United States)

    Fernández-Limón, Claudia; Fernández-Cárdenas, Juan Manuel; Gómez Galindo, Alma Adrianna

    2018-01-01

    Teacher education can benefit directly from experiences in non-formal settings. This article presents a research study with elementary teachers who were teaching in public schools in the state of Nuevo León, México, and participated in a STEM Continuous Professional Development (CPD) workshop. The workshop provided a platform for teachers to…

  7. Technology.

    Science.gov (United States)

    Online-Offline, 1998

    1998-01-01

    Focuses on technology, on advances in such areas as aeronautics, electronics, physics, the space sciences, as well as computers and the attendant progress in medicine, robotics, and artificial intelligence. Describes educational resources for elementary and middle school students, including Web sites, CD-ROMs and software, videotapes, books,…

  8. A hybrid geothermal energy conversion technology: Auxiliary heating of geothermally preheated water or CO2 - a potential solution for low-temperature resources

    Science.gov (United States)

    Saar, Martin; Garapati, Nagasree; Adams, Benjamin; Randolph, Jimmy; Kuehn, Thomas

    2016-04-01

    Safe, sustainable, and economic development of deep geothermal resources, particularly in less favourable regions, often requires employment of unconventional geothermal energy extraction and utilization methods. Often "unconventional geothermal methods" is synonymously and solely used as meaning enhanced geothermal systems, where the permeability of hot, dry rock with naturally low permeability at greater depths (4-6 km), is enhanced. Here we present an alternative unconventional geothermal energy utilization approach that uses low-temperature regions that are shallower, thereby drastically reducing drilling costs. While not a pure geothermal energy system, this hybrid approach may enable utilization of geothermal energy in many regions worldwide that can otherwise not be used for geothermal electricity generation, thereby increasing the global geothermal resource base. Moreover, in some realizations of this hybrid approach that generate carbon dioxide (CO2), the technology may be combined with carbon dioxide capture and storage (CCS) and CO2-based geothermal energy utilization, resulting in a high-efficiency (hybrid) geothermal power plant with a negative carbon footprint. Typically, low- to moderate-temperature geothermal resources are more effectively used for direct heat energy applications. However, due to high thermal losses during transport, direct use requires that the heat resource is located near the user. Alternatively, we show here that if such a low-temperature geothermal resource is combined with an additional or secondary energy resource, the power production is increased compared to the sum from two separate (geothermal and secondary fuel) power plants (DiPippo et al. 1978) and the thermal losses are minimized because the thermal energy is utilized where it is produced. Since Adams et al. (2015) found that using CO2 as a subsurface working fluid produces more net power than brine at low- to moderate-temperature geothermal resource conditions, we

  9. Increasing College Students' Interest and Engagement in STEM: A Comparison of Strategies for Challenging STEM Stereotypes

    Science.gov (United States)

    Shin, Jiyun Elizabeth L.

    Increasing science, technology, engineering, and mathematics (STEM) graduates has become an important part of the education agenda in the U.S. in recent years. Stereotypes about STEM (i.e., belief that STEM abilities are innate, and that European American men are best suited for STEM) have been identified as one of the critical factors that may contribute to low recruitment and retention of STEM students. Drawing from the literatures on biological essentialism and role models, this study compared different strategies for challenging STEM stereotypes among undergraduate students in STEM and non-STEM fields. STEM stereotypes were challenged directly with research articles that provided non-biological explanations for STEM success and interest (a strategy used in the essentialism research) and indirectly with biographies of successful STEM role models who are underrepresented in their field and who succeeded through hard work (a strategy used in the role model research). Contrary to the predictions, exposure to the role model biographies, research articles, or combination of both did not have statistically significant effects on participants' reported STEM interest and academic intentions. Possible explanations for the lack of significant findings as well as suggestions for developing effective interventions to promote STEM engagement among students are discussed.

  10. Research and development of utilization technology of solar thermal system for industrial and other use. Research and development of key technology (energy conversion on technology using chemical reactions); Sangyoyo nado solar system jitsuyoka gijutsu kaihatsu. Yoso gijutsu no kenkyu (kagaku energy henkan gijutsu no kenkyu)

    Energy Technology Data Exchange (ETDEWEB)

    Takita, M [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    Described herein are the results of the FY1994 research program for energy conversion technology using chemical reactions by the aid of solar energy. The demonstration runs were conducted by a bench-scale unit, which was operated stably for 100h, to produce promising results. The catalyst exhibits stable performance, without showing a sign of deactivation. It is found that the heat pump system works well, without being interfered with accumulated by-products. A heat of approximately 2,100kcal/h is recovered. It is confirmed that steam of 150{degree}C and 200{degree}C is generated from hot water of 80{degree}C and 95{degree}C, respectively. The bench-scale runs show a thermal efficiency of around 10%, which is lower than the target level. However, the runs with hydrogen-occluding alloy attain a process thermal efficiency of 30%. The system in which solar collector and chemical heat pump units are combined is evaluated with respect to its economic efficiency and operability for its eventual commercialization. 6 figs., 2 tabs.

  11. After-school enrichment and the activity theory: How can a management service organization assist schools with reducing the achievement gap among minority and non-minority students in science, technology, engineering, and mathematics (STEM) during the after-school hours?

    Science.gov (United States)

    Flowers, Reagan D.

    The primary purpose of this study was to investigate how a management service organization can assist schools with reducing the achievement gap between minority and non-minority students in science, technology, engineering, and mathematics (STEM) during the after-school hours. Developing a strategic plan through creating a program that provides support services for the implementation of hands-on activities in STEM for children during the after-school hours was central to this purpose. This Project Demonstrating Excellence (PDE), a social action project, also presents historical and current after-school program developments in the nation. The study is quantitative and qualitative in nature. Surveys were utilized to quantitatively capture the opinions of participants in the social action project on three specific education related issues: (1) disparity in academic motivation of students to participate in after-school STEM enrichment programs; (2) whether teachers and school administrators saw a need for STEM after-school enrichment; and (3) developing STEM after-school programs that were centered on problem-solving and higher-order thinking skills to develop students' interest in STEM careers. The sample consisted of 50 participants comprised of students, teachers, and administrators. The focus groups and interviews provided the qualitative data for the study. The qualitative sample consisted of 14 participants comprised of students, parents and teachers, administrators, an education consultant, and a corporate sponsor. The empirical data obtained from the study survey, focus groups, and interviews provided a comprehensive profile on the current views and future expectations of STEM after-school enrichment, student and school needs, and community partnerships with STEM companies. Results of the study and review of the implementation of the social action project, C-STEM (communication, science, technology, engineering, and mathematics) Teacher and Student Support

  12. Energy conversion alternatives study

    Science.gov (United States)

    Shure, L. T.

    1979-01-01

    Comparison of coal based energy systems is given. Study identifies and compares various advanced energy conversion systems using coal or coal derived fuels for baselaoad electric power generation. Energy Conversion Alternatives Study (ECAS) reports provede government, industry, and general public with technically consistent basis for comparison of system's options of interest for fossilfired electric-utility application.

  13. Hydrothermal conversion of biomass

    NARCIS (Netherlands)

    Knezevic, D.

    2009-01-01

    This thesis presents research of hydrothermal conversion of biomass (HTC). In this process, hot compressed water (subcritical water) is used as the reaction medium. Therefore this technique is suitable for conversion of wet biomass/ waste streams. By working at high pressures, the evaporation of

  14. Conversations in African Philosophy

    African Journals Online (AJOL)

    JONATHAN

    Conversational philosophy is articulated by Jonathan O. Chimakonam as the new wave of philosophical practice both in “place” and in “space”. This journal adopts and promotes this approach to philosophizing for African philosophy. Readers are encouraged to submit their conversational piece (maximum of 2000 words) ...

  15. Microwave plasma mode conversion

    International Nuclear Information System (INIS)

    Torres, H.S.; Sakanaka, P.H.; Villarroel, C.H.

    1985-01-01

    The behavior of hot electrons during the process of laser-produced plasma is studied. The basic equations of mode conversion from electromagnetic waves to electrostatic waves are presented. It is shown by mode conversion, that, the resonant absorption and parametric instabilities appear simultaneously, but in different plasma regions. (M.C.K.) [pt

  16. Political conversations on Facebook

    DEFF Research Database (Denmark)

    Sørensen, Mads P.

    2016-01-01

    Political conversations are according to theories on deliberative democracy essential to well-functioning democracies. Traditionally these conversations have taken place in face-to-face settings, in e.g. party meetings and town meetings. However, social media such as Facebook and Twitter offers new...... possibilities for online political conversations between citizens and politicians. This paper examines the presence on Facebook and Twitter of Members of the Danish national Parliament, the Folketing, and focusses on a quantitative mapping of the political conversation activities taking place in the threads...... following Facebook posts from Danish Members of Parliament (MPs). The paper shows that, in comparison with previous findings from other countries, Danish MPs have a relatively high degree of engagement in political conversations with citizens on Facebook – and that a large number of citizens follow MPs...

  17. Preparation Matters Most in STEM. Issue Brief

    Science.gov (United States)

    Hayes, Shannon

    2017-01-01

    Serious attention has been directed in recent years towards the need for increasing the number of high school graduates in the United States who are prepared for postsecondary education, training and careers in the fields of science, technology, engineering, and mathematics (STEM). The number of jobs in U.S. STEM occupations grew by 10.5 percent…

  18. Universities Conducting STEM Outreach: A Conceptual Framework

    Science.gov (United States)

    Eilam, Efrat; Bigger, Stephen W.; Sadler, Kirsten; Barry, Fiachra; Bielik, Tom

    2016-01-01

    This paper addresses the positioning of science, technology, engineering and mathematics (STEM) outreach programmes within universities' operations. Though universities in many respects form a rather homogenous international community, there is wide diversity in regard to the provision of STEM outreach by different institutions. To explain this…

  19. STEM Leadership Qualification: Tomorrow's Leaders Today

    Science.gov (United States)

    Williams, Chris

    2009-01-01

    This article features the Science, Technology, Engineering and Mathematics (STEM) Leadership Qualification programme, developed by the Centre for Science Education (CSE) at Sheffield Hallam University in collaboration with Edexcel, which sets out to develop leadership skills and capabilities through contexts in STEM. With six units to complete…

  20. STEM Education in Canada: A Knowledge Synthesis

    Science.gov (United States)

    DeCoito, Isha

    2016-01-01

    Across Canada many initiatives have been initiated to generate more interest in science, technology, engineering, and mathematics (STEM) education; however, no single or comprehensive overview has been conducted that takes into account the impact of these STEM initiatives on teaching/learning outcomes in K-12 education. This knowledge synthesis of…

  1. Psychosocial Factors Impacting STEM Career Selection

    Science.gov (United States)

    Lamb, Richard; Annetta, Leonard; Vallett, David; Firestone, Jonah; Schmitter-Edgecombe, Maureen; Walker, Heather; Deviller, Nicole; Hoston, Douglas

    2018-01-01

    Attention on P-20 science, technology, engineering, and mathematics (STEM) education has increased tremendously in recent years. Many efforts are underway to promote STEM major and career selection across the nation; specifically, in engineering and computer science. The authors' purpose was to examine an underlying profile combinations of latent…

  2. Natural gas conversion. Part VI

    International Nuclear Information System (INIS)

    Iglesia, E.; Spivey, J.J.; Fleisch, T.H.

    2001-01-01

    This volume contains peer-reviewed manuscripts describing the scientific and technological advances presented at the 6th Natural Gas Conversion Symposium held in Alaska in June 2001. This symposium continues the tradition of excellence and the status as the premier technical meeting in this area established by previous meetings. The 6th Natural Gas Conversion Symposium is conducted under the overall direction of the Organizing Committee. The Program Committee was responsible for the review, selection, editing of most of the manuscripts included in this volume. A standing International Advisory Board has ensured the effective long-term planning and the continuity and technical excellence of these meetings. The titles of the contributions are: Impact of syngas generation technology selection on a GTL FPSO; Methane conversion via microwave plasma initiated by a metal initiator; Mechanism of carbon deposit/removal in methane dry reforming on supported metal catalysts; Catalyst-assisted oxidative dehydrogenation of light paraffins in short contact time reactors; Catalytic dehydrogenation of propane over a PtSn/SiO 2 catalyst with oxygen addition: selective oxidation of H2 in the presence of hydrocarbons; Hydroconversion of a mixture of long chain n-paraffins to middle distillate: effect of the operating parameters and products properties; Decomposition/reformation processes and CH4 combustion activity of PdO over Al2O3 supported catalysts for gas turbine applications; Lurgi's mega-methanol technology opens the door for a new era in down-stream applications;Expanding markets for GTL fuels and specialty products; Some critical issues in the analysis of partial oxidation reactions in monolith reactors

  3. Development of FR fuel cycle in Japan (3) - Current state on unified technology of De-nitration conversion and granulation for the simplified pellet fuel production based on microwave heating

    International Nuclear Information System (INIS)

    Suzuki, M.; Ishii, K.; Yamamoto, T.; Kato, Y.; Kurita, T.; Yoshimoto, K.; Kihara, Y.; Namekawa, T.; Fujii, K. I.

    2008-01-01

    The major experimental results and current state on unified and simplified de-nitration conversion processing are explained. This technology was enabled by the nitrate solutions mixing method which is our original idea proposed in FS phase II project and transferred to present FaCT project where the mass production is the supreme subject. The major results obtained up to present, which are based on the two originalities, are as follows; (1) The mixing rate of the plutonium nitrate solution (PNS) into the uranium nitrate solution (UNS) was satisfactorily adjusted by the feeding of 0.5 litter step, (2) Excellent size uniformity around 10 μm was obtained in the MOX powders including 30 wt% of PUO 2 products, (3) In the microwave heating, a mild and stable boiling occurred at whole space in the evaporation dish and the size of bubbles gradually became smaller closing to the finishing stage, (4) The Can coefficient of raw MOX powders containing 30 wt% of PUO 2 was ranged 20-40 just before granulation, being rather difficult to pack them in a die, but after the granulation, the packing rate reached 100 %. (authors)

  4. Annual Report (fiscal 1995, No. 10) of Research Laboratory of Carbonaceous Resources Conversion Technology, Kyoto University; Kyoto Daigaku Kogakubu jushitsu tanso shigen tenkan kogaku jikken shisetsu nenpo (19995 nendo No. 10)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    The report covers Laboratory research activities and a decision that the Laboratory, established in April 1986, will be abolished as scheduled in April 1996. Important coal-related achievements of the Laboratory include the development of a rapid pyrolytic process, studies on coal gasification, propositions for enabling coal to dissolve into general-purpose solvents and for a liquid phase oxidation process, manufacture of advanced-function carbon materials from heavy-weight carbonaceous resources (development of next-generation coke production techniques and of various element techniques for the clean use of coal), etc. As for its activities both domestic and international, the Laboratory, engaged in Education Ministry-financed high-priority scientific research projects, represented the general affairs division in a study titled 'Utilization of various energy resources,' and represented groups participating in other projects titled 'Development of new coal-gasification process' and 'Development of integral conversion process aiming at comprehensive coal utilization.' Furthermore, the Laboratory led the 'Japan-Canada cooperative scientific research relating to the development of technologies for effective coal utilization.' (NEDO)

  5. Annual Report (fiscal 1995, No. 10) of Research Laboratory of Carbonaceous Resources Conversion Technology, Kyoto University; Kyoto Daigaku Kogakubu jushitsu tanso shigen tenkan kogaku jikken shisetsu nenpo (19995 nendo No. 10)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-01

    The report covers Laboratory research activities and a decision that the Laboratory, established in April 1986, will be abolished as scheduled in April 1996. Important coal-related achievements of the Laboratory include the development of a rapid pyrolytic process, studies on coal gasification, propositions for enabling coal to dissolve into general-purpose solvents and for a liquid phase oxidation process, manufacture of advanced-function carbon materials from heavy-weight carbonaceous resources (development of next-generation coke production techniques and of various element techniques for the clean use of coal), etc. As for its activities both domestic and international, the Laboratory, engaged in Education Ministry-financed high-priority scientific research projects, represented the general affairs division in a study titled 'Utilization of various energy resources,' and represented groups participating in other projects titled 'Development of new coal-gasification process' and 'Development of integral conversion process aiming at comprehensive coal utilization.' Furthermore, the Laboratory led the 'Japan-Canada cooperative scientific research relating to the development of technologies for effective coal utilization.' (NEDO)

  6. Annual Report (No. 9, fiscal 1994) of Research Laboratory of Carbonaceous Resources Conversion Technology, Kyoto University; Kyoto Daigaku Kogakubu jushitsu tanso shigen tenkan kogaku jikken shisetsu nenpo (1994 nendo No.9)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    Research activities at the above institute are reported. In an effort to develop advanced coal utilization techniques aiming at reduction in environmental impact, coals of Canadian origin are investigated in cooperation with Canadian researchers. Outstanding among the achievements are Professor Morio Okazaki's 'Study of manipulation of transfer of heat and substance in porous solid bodies' (winner of prize from The Society of Chemical Engineers, Japan), and Professor Tomoyuki Inui's 'Study of fuel synthesis using porous crystalline catalysts' (winner of prize from The Japan Institute of Energy). Various studies are now under way, which include the development of a technique of high-efficiency pyrolysis for coal etc. at the Research Laboratory of Carbonaceous Resources Conversion Technology; development of a zeolite separation membrane on a ceramic filter at the Hashimoto Laboratory specializing in chemical engineering; measurement of the effect of hydrostatic pressure in active carbon adsorption, research on the state of liquid phase adsorption, etc., at the Okazaki Laboratory; analysis of heated fluid in porous structures by means of the lattice Boltzmann method etc. at the Ogino Laboratory; research on coal liquefaction using iron/sulfur-based catalysts etc. at the Watanabe Laboratory. (NEDO)

  7. Annual Report (No. 9, fiscal 1994) of Research Laboratory of Carbonaceous Resources Conversion Technology, Kyoto University; Kyoto Daigaku Kogakubu jushitsu tanso shigen tenkan kogaku jikken shisetsu nenpo (1994 nendo No.9)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-06-01

    Research activities at the above institute are reported. In an effort to develop advanced coal utilization techniques aiming at reduction in environmental impact, coals of Canadian origin are investigated in cooperation with Canadian researchers. Outstanding among the achievements are Professor Morio Okazaki's 'Study of manipulation of transfer of heat and substance in porous solid bodies' (winner of prize from The Society of Chemical Engineers, Japan), and Professor Tomoyuki Inui's 'Study of fuel synthesis using porous crystalline catalysts' (winner of prize from The Japan Institute of Energy). Various studies are now under way, which include the development of a technique of high-efficiency pyrolysis for coal etc. at the Research Laboratory of Carbonaceous Resources Conversion Technology; development of a zeolite separation membrane on a ceramic filter at the Hashimoto Laboratory specializing in chemical engineering; measurement of the effect of hydrostatic pressure in active carbon adsorption, research on the state of liquid phase adsorption, etc., at the Okazaki Laboratory; analysis of heated fluid in porous structures by means of the lattice Boltzmann method etc. at the Ogino Laboratory; research on coal liquefaction using iron/sulfur-based catalysts etc. at the Watanabe Laboratory. (NEDO)

  8. WITHDRAWN: Generation of a human induced pluripotent stem cell line from urinary cells of a healthy donor using integration free Sendai technology.

    Science.gov (United States)

    Rossbach, Bella; Hildebrand, Laura; El-Ahmad, Linda; Stachelscheid, Harald; Reinke, Petra; Kurtz, Andreas

    2016-01-01

    The Publisher regrets that this article is an accidental duplication of an article that has already been published in Stem Cell Res., 16 (2016) 133–136, http://dx.doi.org/10.1016/j.scr.2015.12.021. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  9. Technology

    Directory of Open Access Journals (Sweden)

    Xu Jing

    2016-01-01

    Full Text Available The traditional answer card reading method using OMR (Optical Mark Reader, most commonly, OMR special card special use, less versatile, high cost, aiming at the existing problems proposed a method based on pattern recognition of the answer card identification method. Using the method based on Line Segment Detector to detect the tilt of the image, the existence of tilt image rotation correction, and eventually achieve positioning and detection of answers to the answer sheet .Pattern recognition technology for automatic reading, high accuracy, detect faster

  10. Uranium conversion; Urankonvertering

    Energy Technology Data Exchange (ETDEWEB)

    Oliver, Lena; Peterson, Jenny; Wilhelmsen, Katarina [Swedish Defence Research Agency (FOI), Stockholm (Sweden)

    2006-03-15

    FOI, has performed a study on uranium conversion processes that are of importance in the production of different uranium compounds in the nuclear industry. The same conversion processes are of interest both when production of nuclear fuel and production of fissile material for nuclear weapons are considered. Countries that have nuclear weapons ambitions, with the intention to produce highly enriched uranium for weapons purposes, need some degree of uranium conversion capability depending on the uranium feed material available. This report describes the processes that are needed from uranium mining and milling to the different conversion processes for converting uranium ore concentrate to uranium hexafluoride. Uranium hexafluoride is the uranium compound used in most enrichment facilities. The processes needed to produce uranium dioxide for use in nuclear fuel and the processes needed to convert different uranium compounds to uranium metal - the form of uranium that is used in a nuclear weapon - are also presented. The production of uranium ore concentrate from uranium ore is included since uranium ore concentrate is the feed material required for a uranium conversion facility. Both the chemistry and principles or the different uranium conversion processes and the equipment needed in the processes are described. Since most of the equipment that is used in a uranium conversion facility is similar to that used in conventional chemical industry, it is difficult to determine if certain equipment is considered for uranium conversion or not. However, the chemical conversion processes where UF{sub 6} and UF{sub 4} are present require equipment that is made of corrosion resistant material.

  11. Thermionic conversion reactor technology assessment. Final report

    International Nuclear Information System (INIS)

    1984-02-01

    The in-core thermionic space nuclear power supply may be the only identified reactor-power concept that can meet the SP-100 size functional requirements with demonstrated state-of-the-art reactor system and space-qualified power system component temperatures. The SP-100 configuration limits provide a net 40 m 2 of primary non-deployed radiator area. If a reasonable 7-year degradation allowance of 15% to 20% is provided then the beginning of life (BOL) net power output requirement is about 120 kWe. Consequently, the SP-100 power system must produce a P/A of 2.7 kWe/m 2 . This non-deployed radiator area power density performance can only be reasonably achieved by the thermionic in-core convertr system, the potassium Rankine turbine system and the Stirling engine system. The purpose of this study is to examine past and current tests and data, and to assess the potential for successful development of suitable fueled-thermionic converters that will meet SP-100 and growth requirements. The basis for the assessment will be provided and the recommended key developments plan set forth

  12. Socrates and Technology a New Millennium Conversation

    Science.gov (United States)

    Howard, W. Gary

    2006-01-01

    The Socratic Method has impacted thinkers and instructors from Hegel, who moved through the negation to the negation of the negation, to Marx, who viewed history through dialectical materialism, to C.C. Langdell, who introduced case law as an innovative method to study law as a science, to present-day professors who use this method to compel…

  13. FY 1998 annual summary report on International Clean Energy Network Using Hydrogen Conversion (WE-NET) system technology. Subtask 9. Research and evaluation of innovative and leading technologies; 1998 nendo seika hokokusho. Suiso riyo kokusai clean energy system gijutsu (WE-NET) subtask 9 (kakushinteki, sendoteki gijutsu ni kansuru chosa kenkyu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    In order to make useful suggestions and proposals for the International Clean Energy Network Using Hydrogen Conversion (WE-NET) project and thereby to promote the research and development activities, the innovative and leading technologies have been studied, investigated and evaluated. In FY 1998, a total of 6 proposals were collected, and evaluated to prioritize for the conceptual studies. These are related to methanol-fueled power generation turbine system, conceptual design of high-efficiency production system for high-efficiency solar cell by the 10 GW/y scale production process, investigation of potential of wind power, CO2 recycling methanol fuel cell, investigation of catalysis materials for hydrogen combustion and catalytic combustion systems, development of reversible high-temperature steam electrolysis cell/solid oxide fuel cell by the synthesis from aqueous solutions, and mobile heat recovery hydrogen production system. Promising technologies to be reflected on the WE-NET project were examined, based on the new technologies acquired from the research and investigation so far. As a result, two candidates were selected; hydrogen liquefaction by magnetic refrigeration technology, and catalytic combustion gas turbine. (NEDO)

  14. Solar energy conversion systems

    CERN Document Server

    Brownson, Jeffrey R S

    2013-01-01

    Solar energy conversion requires a different mind-set from traditional energy engineering in order to assess distribution, scales of use, systems design, predictive economic models for fluctuating solar resources, and planning to address transient cycles and social adoption. Solar Energy Conversion Systems examines solar energy conversion as an integrative design process, applying systems thinking methods to a solid knowledge base for creators of solar energy systems. This approach permits different levels of access for the emerging broad audience of scientists, engineers, architects, planners

  15. Energy conversion statics

    CERN Document Server

    Messerle, H K; Declaris, Nicholas

    2013-01-01

    Energy Conversion Statics deals with equilibrium situations and processes linking equilibrium states. A development of the basic theory of energy conversion statics and its applications is presented. In the applications the emphasis is on processes involving electrical energy. The text commences by introducing the general concept of energy with a survey of primary and secondary energy forms, their availability, and use. The second chapter presents the basic laws of energy conversion. Four postulates defining the overall range of applicability of the general theory are set out, demonstrating th

  16. Uranium Conversion & Enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Karpius, Peter Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-02-06

    The isotopes of uranium that are found in nature, and hence in ‘fresh’ Yellowcake’, are not in relative proportions that are suitable for power or weapons applications. The goal of conversion then is to transform the U3O8 yellowcake into UF6. Conversion and enrichment of uranium is usually required to obtain material with enough 235U to be usable as fuel in a reactor or weapon. The cost, size, and complexity of practical conversion and enrichment facilities aid in nonproliferation by design.

  17. Postoperative conversion disorder.

    Science.gov (United States)

    Afolabi, Kola; Ali, Sameer; Gahtan, Vivian; Gorji, Reza; Li, Fenghua; Nussmeier, Nancy A

    2016-05-01

    Conversion disorder is a psychiatric disorder in which psychological stress causes neurologic deficits. A 28-year-old female surgical patient had uneventful general anesthesia and emergence but developed conversion disorder 1 hour postoperatively. She reported difficulty speaking, right-hand numbness and weakness, and right-leg paralysis. Neurologic examination and imaging revealed no neuronal damage, herniation, hemorrhage, or stroke. The patient mentioned failing examinations the day before surgery and discontinuing her prescribed antidepressant medication, leading us to diagnose conversion disorder, with eventual confirmation by neuroimaging and follow-up examinations. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Uranium conversion wastes

    International Nuclear Information System (INIS)

    Vicente, R.; Dellamano, J.C.

    1989-12-01

    A set of mathematical equations was developed and used to estimate the radiological significance of each radionuclide potentially present in the uranium refining industry effluents. The equations described the evolution in time of the radionuclides activities in the uranium fuel cycle, from mining and milling, through the yellowcake, till the conversion effluents. Some radionuclides that are not usually monitored in conversion effluents (e.g. Pa-231 and Ac-227) were found to be potentially relevant from the radiological point of view in conversion facilities, and are certainly relevant in mining and milling industry, at least in a few waste streams. (author) [pt

  19. Freely flowing conversations

    DEFF Research Database (Denmark)

    Aakjær, Marie Kirstejn; Andrade, David; Dexters, Peter

    and in regards to rehabilitation efforts. In the context of prisons UDI is inspired by the complexity approach (Stacey 2005). We seek to facilitate freely flowing conversations between inmates, staff and managers – pushing the boundaries of existing norms, roles and beliefs. In the end however we rely...... relations by changing conversations. Through the theoretical framework of the complexity approach, we discuss how this may lead to organizational change. Finally we suggest that inviting inmates to take part in conversations about core organizational development may be a fundamental strategy in trying...

  20. Women in STEM hit by discrimination

    Science.gov (United States)

    Randall, Ian

    2016-02-01

    Almost a third of women in science, technology, engineering and mathematics (STEM) in Australia are considering leaving their job within the next five years, according to a survey by the employee association Professionals Australia.

  1. 2010 Federal STEM Education Inventory Data Set

    Data.gov (United States)

    Office of Science and Technology Policy, Executive Office of the President — This data set provides information for STEM education (pre-kindergarten through graduate) investments funded by Federal agencies at the level of $300,000 or above.

  2. Financial Barriers to STEM Study in College: Causal Effect Estimates of Need-Based Grants on the Pursuit and Completion of Courses and Degrees in STEM Fields

    Science.gov (United States)

    Castleman, Benjamin L.; Long, Bridget Terry; Mabel, Zachary A.

    2014-01-01

    The fastest growing supply of jobs in the United States today is in Science, Technology, Engineering, and Mathematics (STEM) fields. Yet despite the availability of work in STEM, there is not a sufficient supply of workers to fill open positions. Amidst the growing demand for STEM workers, educational achievement and attainment in STEM fields in…

  3. Expanding STEM opportunities through inclusive STEM-focused high schools.

    Science.gov (United States)

    Means, Barbara; Wang, Haiwen; Wei, Xin; Lynch, Sharon; Peters, Vanessa; Young, Viki; Allen, Carrie

    2017-09-01

    Inclusive STEM high schools (ISHSs) (where STEM is science, technology, engineering, and mathematics) admit students on the basis of interest rather than competitive examination. This study examines the central assumption behind these schools-that they provide students from subgroups underrepresented in STEM with experiences that equip them academically and attitudinally to enter and stay in the STEM pipeline. Hierarchical modeling was applied to data from student surveys and state longitudinal data records for 5113 students graduating from 39 ISHSs and 22 comprehensive high schools in North Carolina and Texas. Compared to peers from the same demographic group with similar Grade 8 achievement levels, underrepresented minority and female ISHS students in both states were more likely to undertake advanced STEM coursework. Hispanics in Texas and females in both states expressed more STEM career interest in Grade 12 if they attended an ISHS. Positive relationships between ISHS attendance and grade point average were found in the total sample and each subgroup in North Carolina. Positive ISHS advantages in terms of test scores for the total student sample were found for science in both states and for mathematics in Texas. For the various student subgroups, test score differences favored the ISHS samples but attained statistical significance only for African Americans' science achievement scores in the Texas study.

  4. Trends and Challenges in Catalytic Biomass Conversion

    DEFF Research Database (Denmark)

    Osmundsen, Christian Mårup; Egeblad, Kresten; Taarning, Esben

    2013-01-01

    The conversion of biomass to the plethora of chemicals used in modern society is one of the major challenges of the 21st century. Due to the significant differences between biomass resources and the current feedstock, crude oil, new technologies need to be developed encompassing all steps...... in the value chain, from pretreatment to purification. Heterogeneous catalysis is at the heart of the petrochemical refinery and will likely play an equally important role in the future biomass-based chemical industry. Three potentially important routes to chemicals from biomass are highlighted in this chapter....... The conversion of biomass-derived substrates, such as glycerol, by hydrogenolysis to the important chemicals ethylene glycol and propane diols. Secondly, the conversion of carbohydrates by Lewis acidic zeolites to yield alkyl lactates, and finally the conversion of lignin, an abundant low value source of biomass...

  5. Condenser design for AMTEC power conversion

    Science.gov (United States)

    Crowley, Christopher J.

    1991-01-01

    The condenser and the electrodes are the two elements of an alkali metal thermal-to-electric conversion (AMTEC) cell which most greatly affect the energy conversion performance. A condenser is described which accomplishes two critical functions in an AMTEC cell: management of the fluid under microgravity conditions and optimization of conversion efficiency. The first function is achieved via the use of a controlled surface shape, along with drainage grooves and arteries to collect the fluid. Capillary forces manage the fluid in microgravity and dominate hydrostatic effects on the ground so the device is ground-testable. The second function is achieved via a smooth film of highly reflective liquid sodium on the condensing surface, resulting in minimization of parasitic heat losses due to radiation heat transfer. Power conversion efficiencies of 25 percent to 30 percent are estimated with this condenser using present technology for the electrodes.

  6. Going beyond Fun in STEM

    Science.gov (United States)

    Pittinsky, Todd L.; Diamante, Nicole

    2015-01-01

    The United States education system must improve its ability to produce scientists, engineers, and programmers. Despite numerous national, state, and local efforts to make the study of STEM (science, technology, engineering, and mathematics) subjects more fun in K-12, initial interest in those subjects drops off precipitously in middle and later…

  7. Cyberinfrastructure for Undergraduate STEM Education

    Science.gov (United States)

    Swaid, Samar

    2013-01-01

    Cyberinfrastructure (CI) is a term that usually appears in scientific research, but rarely to be noticed as a scientific education tool. In this paper, I describe a transformative Cyberinfrastructure-based strategy to improve Science, Technology, Engineering and Mathematics (STEM) education at one of the historically black colleges. This strategy…

  8. STEM Equality and Diversity Toolkit

    Science.gov (United States)

    Collins, Jill

    2011-01-01

    In 2008, the Centre for Science Education at Sheffield Hallam University teamed up with VT Enterprise (now Babcock International) in their submission of a successful bid to deliver the national STEM (Science, Technology, Engineering and Maths) Subject Choice and Careers Project. An integral part of the bid was the promotion of equality and…

  9. Bioinspiring an Interest in STEM

    Science.gov (United States)

    Laut, Jeffrey; Bartolini, Tiziana; Porfiri, Maurizio

    2015-01-01

    Attracting K-12 students to pursue careers in science, technology, engineering, and mathematics (STEM) is viewed as a critical element for benefiting both the economy and society. This paper describes an outreach program, conducted in a Brooklyn, New York, USA, public middle school, aimed at educating students in mechatronics, biology, and…

  10. Increasing conversion efficiency of two-step photon up-conversion solar cell with a voltage booster hetero-interface.

    Science.gov (United States)

    Asahi, Shigeo; Kusaki, Kazuki; Harada, Yukihiro; Kita, Takashi

    2018-01-17

    Development of high-efficiency solar cells is one of the attractive challenges in renewable energy technologies. Photon up-conversion can reduce the transmission loss and is one of the promising concepts which improve conversion efficiency. Here we present an analysis of the conversion efficiency, which can be increased by up-conversion in a single-junction solar cell with a hetero-interface that boosts the output voltage. We confirm that an increase in the quasi-Fermi gap and substantial photocurrent generation result in a high conversion efficiency.

  11. Pathways in STEM: Factors Affecting the Retention and Attrition of Talented Men and Women from the STEM Pipeline

    Science.gov (United States)

    Heilbronner, Nancy N.

    2009-01-01

    Many men and women who are talented in science, technology, engineering, and/or mathematics (STEM) choose not to pursue undergraduate majors or careers in these fields. To develop talents in STEM, educators must understand the factors that contribute to an individual's retention in STEM domains, as well as the factors that act as barriers to…

  12. Induced Pluripotent Stem Cells for Regenerative Medicine

    OpenAIRE

    Hirschi, Karen K.; Li, Song; Roy, Krishnendu

    2014-01-01

    With the discovery of induced pluripotent stem (iPS) cells, it is now possible to convert differentiated somatic cells into multipotent stem cells that have the capacity to generate all cell types of adult tissues. Thus, there is a wide variety of applications for this technology, including regenerative medicine, in vitro disease modeling, and drug screening/discovery. Although biological and biochemical techniques have been well established for cell reprogramming, bioengineering technologies...

  13. Strategies for future histocompatible stem cell therapy

    DEFF Research Database (Denmark)

    Nehlin, Jan; Barington, Torben

    2009-01-01

    Stem cell therapy based on the safe and unlimited self-renewal of human pluripotent stem cells is envisioned for future use in tissue or organ replacement after injury or disease. A gradual decline of regenerative capacity has been documented among the adult stem cell population in some body organs...... during the aging process. Recent progress in human somatic cell nuclear transfer and inducible pluripotent stem cell technologies has shown that patient-derived nuclei or somatic cells can be reprogrammed in vitro to become pluripotent stem cells, from which the three germ layer lineages can be generated......, genetically identical to the recipient. Once differentiation protocols and culture conditions can be defined and optimized, patient-histocompatible pluripotent stem cells could be directed towards virtually every cell type in the human body. Harnessing this capability to enrich for given cells within...

  14. Therapeutic potential of adult stem cells

    DEFF Research Database (Denmark)

    Serakinci, Nedime; Keith, W. Nicol

    2006-01-01

    is the necessity to be able to identify, select, expand and manipulate cells outside the body. Recent advances in adult stem cell technologies and basic biology have accelerated therapeutic opportunities aimed at eventual clinical applications. Adult stem cells with the ability to differentiate down multiple...... lineages are an attractive alternative to human embryonic stem cells (hES) in regenerative medicine. In many countries, present legislation surrounding hES cells makes their use problematic, and indeed the origin of hES cells may represent a controversial issue for many communities. However, adult stem...... cells are not subject to these issues. This review will therefore focus on adult stem cells. Based on their extensive differentiation potential and, in some cases, the relative ease of their isolation, adult stem cells are appropriate for clinical development. Recently, several observations suggest...

  15. Stem cell biobanks.

    Science.gov (United States)

    Bardelli, Silvana

    2010-04-01

    Stem cells contribute to innate healing and harbor a promising role for regenerative medicine. Stem cell banking through long-term storage of different stem cell platforms represents a fundamental source to preserve original features of stem cells for patient-specific clinical applications. Stem cell research and clinical translation constitute fundamental and indivisible modules catalyzed through biobanking activity, generating a return of investment.

  16. Mining Conversational Social Video

    OpenAIRE

    Biel, Joan-Isaac

    2013-01-01

    The ubiquity of social media in our daily life, the intense user participation, and the explo- sion of multimedia content have generated an extraordinary interest from computer and social scientists to investigate the traces left by users to understand human behavior online. From this perspective, YouTube can be seen as the largest collection of audiovisual human behavioral data, among which conversational video blogs (vlogs) are one of the basic formats. Conversational vlogs have evolved fro...

  17. Persuasion detection in conversation

    OpenAIRE

    Gilbert, Henry T.

    2010-01-01

    Approved for public release; distribution is unlimited In this thesis, we present a system for annotating persuasion in conversation based on a social-psychological model. We augmented the social model developed by James Cialdini with some of our own categories for annotators to label. The conversations consisted of 37 hostage negotiation transcripts from private and public sources, with all personal information removed from the private source transcripts. We evaluated the level of agre...

  18. Perspective on direct conversion

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, W B

    1963-10-15

    The objective of direct conversion is high electrical output for minimum total cost, and not always high conversion efficiency. The wide range of techniques embracing cryogenics and hot plasma derives from the special requirements of source, environment, and application. Sources include solar and other radiation, nuclear fission and fusion, chemical energy, and heat. Environments and applications range from space vehicles to submarines and from giant power networks to isolated buoys and pocket devices. (auth)

  19. Conversion of Semipalatinsk test site

    International Nuclear Information System (INIS)

    Cherepnin, Yu. S.

    1997-01-01

    The conversion of the former defense enterprises of STS (Semipalatinsk Test Sate) started under very difficult conditions, when not only research and production activity, but all social life of Kurchatov city were conversed which was caused by a fast curtailment and restationing of Russian military units from the test site. A real risk of a complete destruction of the whole research and production structure of the city existed. From this point of view, the decision of the Republic of Kazakhstan Government to create the National Nuclear Center on the base of the test site research enterprises was actual and timely. During 1993, three research institutes of NNC RK - Institute of Atomic Energy, Institute of Geophysics Research and Institute of Radiation Safety and Environment were established. This decision, under conditions of the Ussr disintegration and liquidation of the test site military divisions, allowed to preserve the qualified personnel, to provide and follow-up the operation of nuclear dangerous facilities, to develop and start the realization of the full scale conversion program.At present time, directions and structure of basic research work in NNC RK are as follows: - liquidation of nuclear explosions consequences; - liquidation of technological infrastructure used for preparation and conduction of nuclear weapon testing; - creation of technology, equipment and places for acceptance and storage of radioactive wastes; - working out of atomic energy development conception in Kazakhstan; - study of reactor core melt behavior under severe accidents in NPP; - development of methods and means of nuclear testing detection, continuous monitoring of nuclear explosions; - experimental work on a study of structure materials behavior of ITER thermonuclear reactor; - creation of industries requiring a lage implementation of science

  20. Narrative Inquiry on the Teaching of STEM to Blind High School Students

    Directory of Open Access Journals (Sweden)

    Idalis Villanueva

    2017-12-01

    Full Text Available This study aimed to elevate the experiences and voices of teachers who led the STEM informal education program summer series: National Federation of the Blind Engineering Quotient (NFB EQ. Through its integration with science, technology, engineering, and math (STEM, NFB EQ opened opportunities from 2013–2016 in Baltimore, Maryland, for 60 blind students (Grades 9–12 to learn about engineering. The purpose of this narrative inquiry study was to understand how teachers foster interest towards STEM among blind students. The participants were two sighted teachers, one blind teacher, one sighted teacher–researcher, and one sighted researcher participant. We collected data in the form of field notes, semi-structured interviews, personal narratives, collective narratives, a focus group discussion, and teaching artifacts. We engaged in conversation analysis and used MAXQDA 12 software for data analysis. Guided by the principles of community of practices and universal design for learning, our results identified the importance of teacher awareness and positionalities in guiding blind students’ inclusion and identity in the STEM classroom. Findings also suggest teachers are in a unique position to allow or prevent inclusive opportunities from occurring in their classrooms.

  1. Toward a Framework for Multicultural STEM-Focused Career Interventions

    Science.gov (United States)

    Byars-Winston, Angela

    2015-01-01

    Numerous federal and national commissions have called for policies, funds, and initiatives aimed at expanding the nation's science, technology, engineering, and mathematics (STEM) workforce and education investments to create a significantly larger, more diverse talent pool of individuals who pursue technical careers. Career development professionals are poised to contribute to the equity discourse about broadening STEM participation. However, few are aware of STEM-related career development matters, career opportunities and pathways, or strategies for promoting STEM pursuits. The author summarizes STEM education and workforce trends and articulates an equity imperative for broadening and diversifying STEM participation. The author then offers a multicultural STEM-focused career development framework to encourage career development professionals' knowledge and awareness of STEM education and careers and delineates considerations for practice aimed at increasing the attainment and achievement of diverse groups in STEM fields. PMID:25750480

  2. Encouraging Creativity in a STEM Classroom

    Directory of Open Access Journals (Sweden)

    David L. Byrum

    2015-01-01

    Full Text Available The Thailand Ministry of Education’s “Institute for the Promotion of Teaching Science and Technology” (IPST uses the following as its working definition of STEM: “STEM education integrates science, engineering, technology and mathematics focusing on the application of knowledge to real-life problem solving and development of new products or procedures benefiting daily living and livelihood. STEM education infuses the engineering process into the existing science, mathematics and technology curricula to enable utilization of the knowledge to solve actual problems and aid future occupational undertakings.”

  3. Electrochemistry of Nanocomposite Materials for Energy Conversion

    OpenAIRE

    Boni, Alessandro

    2016-01-01

    Energy is the most relevant technological issue that the world experiences today, and the development of efficient technologies able to store and convert energy in different forms is urgently needed. The storage of electrical energy is of major importance and electrochemical processes are particularly suited for the demanding task of an efficient inter-conversion. A potential strategy is to store electricity into the chemical bonds of electrogenerated fuels, like hydrogen and/or energy-den...

  4. Stem cells in the human breast

    DEFF Research Database (Denmark)

    Petersen, Ole William; Polyak, Kornelia

    2010-01-01

    The origins of the epithelial cells participating in the development, tissue homeostasis, and cancer of the human breast are poorly understood. However, emerging evidence suggests a role for adult tissue-specific stem cells in these processes. In a hierarchical manner, these generate the two main...... mammary cell lineages, producing an increasing number of cells with distinct properties. Understanding the biological characteristics of human breast stem cells and their progeny is crucial in attempts to compare the features of normal stem cells and cancer precursor cells and distinguish these from...... nonprecursor cells and cells from the bulk of a tumor. A historical overview of research on human breast stem cells in primary tissue and in culture reveals the progress that has been made in this area, whereas a focus on the cell-of-origin and reprogramming that occurs during neoplastic conversion provides...

  5. Biomass Thermochemical Conversion Program. 1984 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Schiefelbein, G.F.; Stevens, D.J.; Gerber, M.A.

    1985-01-01

    The objective of the program is to generate scientific data and conversion process information that will lead to establishment of cost-effective process for converting biomass resources into clean fuels. The goal of the program is to develop the data base for biomass thermal conversion by investigating the fundamental aspects of conversion technologies and by exploring those parameters that are critical to the conversion processes. The research activities can be divided into: (1) gasification technology; (2) liquid fuels technology; (3) direct combustion technology; and (4) program support activities. These activities are described in detail in this report. Outstanding accomplishments during fiscal year 1984 include: (1) successful operation of 3-MW combustor/gas turbine system; (2) successful extended term operation of an indirectly heated, dual bed gasifier for producing medium-Btu gas; (3) determination that oxygen requirements for medium-Btu gasification of biomass in a pressurized, fluidized bed gasifier are low; (4) established interdependence of temperature and residence times on biomass pyrolysis oil yields; and (5) determination of preliminary technical feasibility of thermally gasifying high moisture biomass feedstocks. A bibliography of 1984 publications is included. 26 figs., 1 tab.

  6. Research on fabrication technology for thin film solar cells for practical use. Technological development for qualitative improvement (improvement of conversion efficiency of amorphous silicon solar cells after degradation); Usumaku taiyo denchi seizo gijutsu no jitsuyoka kenkyu. Kohinshitsuka gijutsu (amorphous taiyo denchi no shoki rekkago koritsu kojo no gijutsu kaihatsu)

    Energy Technology Data Exchange (ETDEWEB)

    Tatsuta, M [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1994-12-01

    This paper reports the study results on technological development for qualitative improvement of a-Si solar cells after initial degradation in fiscal 1994. On the fabrication technology of light-stable a-Si films, the film formation method possible to control combined hydrogen by repetitive formation/treatment was developed. The obtained high-quality light-stable a-Si film was featured by low defect density in a wide optical band gap range, and defect density of nearly 3 {times} 10{sup 16}/cm{sup -3} after light irradiation. The light degradation rate of the cell where the a-Si film was applied to i layer was relatively stable by 10% or less. The a-Si/a-Si double-layer tandem cell fabricated by this technology produced a high conversion efficiency of 10.5%. By applying {mu}c-Si material to photoactive layer as narrow band gap material, the cell with optical sensitivity even in long wavelength ranges more than 1000nm was obtained. The a-Si/{mu}c-Si double-layer tandem cell produced an initial efficiency of 8.0% and an efficiency after degradation of 7.5%. 12 figs., 3 tabs.

  7. A Prospective Treatment Option for Lysosomal Storage Diseases: CRISPR/Cas9 Gene Editing Technology for Mutation Correction in Induced Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Chloe L. Christensen

    2017-02-01

    Full Text Available Ease of design, relatively low cost and a multitude of gene-altering capabilities have all led to the adoption of the sophisticated and yet simple gene editing system: clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9. The CRISPR/Cas9 system holds promise for the correction of deleterious mutations by taking advantage of the homology directed repair pathway and by supplying a correction template to the affected patient’s cells. Currently, this technique is being applied in vitro in human-induced pluripotent stem cells (iPSCs to correct a variety of severe genetic diseases, but has not as of yet been used in iPSCs derived from patients affected with a lysosomal storage disease (LSD. If adopted into clinical practice, corrected iPSCs derived from cells that originate from the patient themselves could be used for therapeutic amelioration of LSD symptoms without the risks associated with allogeneic stem cell transplantation. CRISPR/Cas9 editing in a patient’s cells would overcome the costly, lifelong process associated with currently available treatment methods, including enzyme replacement and substrate reduction therapies. In this review, the overall utility of the CRISPR/Cas9 gene editing technique for treatment of genetic diseases, the potential for the treatment of LSDs and methods currently employed to increase the efficiency of this re-engineered biological system will be discussed.

  8. A Prospective Treatment Option for Lysosomal Storage Diseases: CRISPR/Cas9 Gene Editing Technology for Mutation Correction in Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Christensen, Chloe L; Choy, Francis Y M

    2017-02-24

    Ease of design, relatively low cost and a multitude of gene-altering capabilities have all led to the adoption of the sophisticated and yet simple gene editing system: clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 (CRISPR/Cas9). The CRISPR/Cas9 system holds promise for the correction of deleterious mutations by taking advantage of the homology directed repair pathway and by supplying a correction template to the affected patient's cells. Currently, this technique is being applied in vitro in human-induced pluripotent stem cells (iPSCs) to correct a variety of severe genetic diseases, but has not as of yet been used in iPSCs derived from patients affected with a lysosomal storage disease (LSD). If adopted into clinical practice, corrected iPSCs derived from cells that originate from the patient themselves could be used for therapeutic amelioration of LSD symptoms without the risks associated with allogeneic stem cell transplantation. CRISPR/Cas9 editing in a patient's cells would overcome the costly, lifelong process associated with currently available treatment methods, including enzyme replacement and substrate reduction therapies. In this review, the overall utility of the CRISPR/Cas9 gene editing technique for treatment of genetic diseases, the potential for the treatment of LSDs and methods currently employed to increase the efficiency of this re-engineered biological system will be discussed.

  9. Oceanography and Geoscience Scholars at Texas A&M University Funded through the NSF S-STEM (Scholarships in Science, Technology, Engineering and Mathematics) Program

    Science.gov (United States)

    Richardson, M. J.; Gardner, W. D.

    2016-02-01

    Over the last seven years we have led the creation and implementation of the Oceanography and Geoscience Scholars programs at Texas A&M University. Through these programs we have been able to provide scholarship support for 92 undergraduates in Geosciences and 29 graduate students in Oceanography. Fifty-seven undergraduate scholars have graduated in Geosciences: 30 undergraduate students in Meteorology, 7 in Geology, and 20 in Environmental Geosciences. Two students have graduated in other STEM disciplines. Twenty-four students are in the process of completing their undergraduate degrees in STEM disciplines. Twenty-three students have graduated with MS or PhD degrees in Oceanography and five PhD students are completing their dissertations. As specified in the program solicitation all of the scholars are academically talented students with demonstrated financial need as defined by the FAFSA (Free Application for Federal Student Aid). We have endeavored to recruit students from underrepresented groups. One-third of the undergraduate scholars were from underrepresented groups; 28% of the graduate students. We will present the challenges and successes of these programs.

  10. NOTCH-Mediated Maintenance and Expansion of Human Bone Marrow Stromal/Stem Cells: A Technology Designed for Orthopedic Regenerative Medicine.

    Science.gov (United States)

    Dong, Yufeng; Long, Teng; Wang, Cuicui; Mirando, Anthony J; Chen, Jianquan; O'Keefe, Regis J; Hilton, Matthew J

    2014-12-01

    Human bone marrow-derived stromal/stem cells (BMSCs) have great therapeutic potential for treating skeletal disease and facilitating skeletal repair, although maintaining their multipotency and expanding these cells ex vivo have proven difficult. Because most stem cell-based applications to skeletal regeneration and repair in the clinic would require large numbers of functional BMSCs, recent research has focused on methods for the appropriate selection, expansion, and maintenance of BMSC populations during long-term culture. We describe here a novel biological method that entails selection of human BMSCs based on NOTCH2 expression and activation of the NOTCH signaling pathway in cultured BMSCs via a tissue culture plate coated with recombinant human JAGGED1 (JAG1) ligand. We demonstrate that transient JAG1-mediated NOTCH signaling promotes human BMSC maintenance and expansion while increasing their skeletogenic differentiation capacity, both ex vivo and in vivo. This study is the first of its kind to describe a NOTCH-mediated methodology for the maintenance and expansion of human BMSCs and will serve as a platform for future clinical or translational studies aimed at skeletal regeneration and repair. ©AlphaMed Press.

  11. Learning from Our Global Competitors: A Comparative Analysis of Science, Technology, Engineering and Mathematics (STEM) Education Pipelines in the United States, Mainland China and Taiwan

    Science.gov (United States)

    Chow, Christina M.

    2011-01-01

    Maintaining a competitive edge within the 21st century is dependent on the cultivation of human capital, producing qualified and innovative employees capable of competing within the new global marketplace. Technological advancements in communications technology as well as large scale, infrastructure development has led to a leveled playing field…

  12. From Flavr Savr Tomatoes to STEM Cell Therapy: Young People's Understandings of Gene Technology, 15 Years On

    Science.gov (United States)

    Lewis, Jenny

    2014-01-01

    This paper explores knowledge and understanding of basic genetics and gene technologies in school students who have been taught to a "science for all" National Curriculum and compares 482 students in 1995 (gene technology was a new and rapidly developing area of science with potential to impact on everyday life; the first cohort of…

  13. Single-cell sequencing in stem cell biology.

    Science.gov (United States)

    Wen, Lu; Tang, Fuchou

    2016-04-15

    Cell-to-cell variation and heterogeneity are fundamental and intrinsic characteristics of stem cell populations, but these differences are masked when bulk cells are used for omic analysis. Single-cell sequencing technologies serve as powerful tools to dissect cellular heterogeneity comprehensively and to identify distinct phenotypic cell types, even within a 'homogeneous' stem cell population. These technologies, including single-cell genome, epigenome, and transcriptome sequencing technologies, have been developing rapidly in recent years. The application of these methods to different types of stem cells, including pluripotent stem cells and tissue-specific stem cells, has led to exciting new findings in the stem cell field. In this review, we discuss the recent progress as well as future perspectives in the methodologies and applications of single-cell omic sequencing technologies.

  14. Boiler conversions for biomass

    Energy Technology Data Exchange (ETDEWEB)

    Kinni, J [Tampella Power Inc., Tampere (Finland)

    1997-12-31

    Boiler conversions from grate- and oil-fired boilers to bubbling fluidized bed combustion have been most common in pulp and paper industry. Water treatment sludge combustion, need for additional capacity and tightened emission limits have been the driving forces for the conversion. To accomplish a boiler conversion for biofuel, the lower part of the boiler is replaced with a fluidized bed bottom and new fuel, ash and air systems are added. The Imatran Voima Rauhalahti pulverized-peat-fired boiler was converted to bubbling fluidized bed firing in 1993. In the conversion the boiler capacity was increased by 10 % to 295 MWth and NO{sub x} emissions dropped. In the Kymmene Kuusankoski boiler, the reason for conversion was the combustion of high chlorine content biosludge. The emissions have been under general European limits. During the next years, the emission limits will tighten and the boilers will be designed for most complete combustion and compounds, which can be removed from flue gases, will be taken care of after the boiler. (orig.) 3 refs.

  15. Boiler conversions for biomass

    Energy Technology Data Exchange (ETDEWEB)

    Kinni, J. [Tampella Power Inc., Tampere (Finland)

    1996-12-31

    Boiler conversions from grate- and oil-fired boilers to bubbling fluidized bed combustion have been most common in pulp and paper industry. Water treatment sludge combustion, need for additional capacity and tightened emission limits have been the driving forces for the conversion. To accomplish a boiler conversion for biofuel, the lower part of the boiler is replaced with a fluidized bed bottom and new fuel, ash and air systems are added. The Imatran Voima Rauhalahti pulverized-peat-fired boiler was converted to bubbling fluidized bed firing in 1993. In the conversion the boiler capacity was increased by 10 % to 295 MWth and NO{sub x} emissions dropped. In the Kymmene Kuusankoski boiler, the reason for conversion was the combustion of high chlorine content biosludge. The emissions have been under general European limits. During the next years, the emission limits will tighten and the boilers will be designed for most complete combustion and compounds, which can be removed from flue gases, will be taken care of after the boiler. (orig.) 3 refs.

  16. Dragons, Ladybugs, and Softballs: Girls' STEM Engagement with Human-Centered Robotics

    Science.gov (United States)

    Gomoll, Andrea; Hmelo-Silver, Cindy E.; Šabanovic, Selma; Francisco, Matthew

    2016-01-01

    Early experiences in science, technology, engineering, and math (STEM) are important for getting youth interested in STEM fields, particularly for girls. Here, we explore how an after-school robotics club can provide informal STEM experiences that inspire students to engage with STEM in the future. Human-centered robotics, with its emphasis on the…

  17. Effects of Transferring to STEM-Focused Charter and Magnet Schools on Student Achievement

    Science.gov (United States)

    Judson, Eugene

    2014-01-01

    There have been strong calls to action in recent years to promote both school choice and the learning of science, technology, engineering, and mathematics (STEM). This has led to the burgeoning development of STEM-focused schools. Nine STEM-focused charter and 2 STEM-focused magnet schools that serve elementary-aged students were examined to…

  18. Biochemical Conversion: Using Enzymes, Microbes, and Catalysis to Make Fuels and Chemicals

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-07-26

    This fact sheet describes the Bioenergy Technologies Office's biochemical conversion work and processes. BETO conducts collaborative research, development, and demonstration projects to improve several processing routes for the conversion of cellulosic biomass.

  19. Photovoltaic solar energy conversion

    CERN Document Server

    Bauer, Gottfried H

    2015-01-01

    This concise primer on photovoltaic solar energy conversion invites readers to reflect on the conversion of solar light into energy at the most fundamental level and encourages newcomers to the field to help find meaningful answers on how photovoltaic solar energy conversion can work (better), eventually contributing to its ongoing advancement. The book is based on lectures given to graduate students in the Physics Department at the University of Oldenburg over the last two decades, yet also provides an easy-to-follow introduction for doctoral and postdoctoral students from related disciplines such as the materials sciences and electrical engineering. Inspired by classic textbooks in the field, it reflects the author’s own ideas on how to understand, visualize and eventually teach the microscopic physical mechanisms and effects, while keeping the text as concise as possible so as to introduce interested readers to the field and balancing essential knowledge with open questions.

  20. Catalytic Conversion of Carbohydrates

    DEFF Research Database (Denmark)

    Osmundsen, Christian Mårup

    a renewable route to aromatics. The conversion of biomass by high temperature processes is a desirable prospect due to the high volumetric production rates which can be achieved, and the ability of these types of processes to convert a wide range of substrates. Current processes however typically have rather...... with the production of commodity chemicals from the most abundantly available renewable source of carbon, carbohydrates. The production of alkyl lactates by the Lewis acid catalyzed conversion of hexoses is an interesting alternative to current fermentation based processes. A range of stannosilicates were...... to be an efficient initial conversion step in the utilization of biomass for chemicals production. The shift from an oil based chemical industry to one based on renewable resources is bound to happen sooner or later, however the environmental problems associated with the burning of fossil resources means...