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. 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

    2013-01-01

    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 a

  3. Direct conversion technology

    Energy Technology Data Exchange (ETDEWEB)

    Massier, P.F.; Back, L.H.; Ryan, M.A.; Fabris, G.

    1992-01-07

    The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. This report contains progress of research on the Alkali Metal Thermal-to-Electric Converter (AMTEC) and on the Two-Phase Liquid-Metal MHD Electrical Generator (LMMHD) for the period January 1, 1991 through December 31, 1991. Research on AMTEC and on LMMHD was initiated during October 1987. Reports prepared on previous occasions (Refs. 1--5) contain descriptive and performance discussions of the following direct conversion concepts: thermoelectric, pyroelectric, thermionic, thermophotovoltaic, thermoacoustic, thermomagnetic, thermoelastic (Nitionol heat engine); and also, more complete descriptive discussions of AMTEC and LMMHD systems.

  4. 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.

  5. 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...

  6. 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

  7. STEM: Science Technology Engineering Mathematics

    Science.gov (United States)

    Carnevale, Anthony P.; Smith, Nicole; Melton, Michelle

    2011-01-01

    The generative economic power and social influence of Science, Technology, Engineering, and Mathematics (STEM) has made the production of a capable science and engineering workforce a priority among business and policy leaders. They are rightly concerned that without a robust STEM workforce, the nation will become less competitive in the global…

  8. The Role of Conversation in Technology Education

    Science.gov (United States)

    Fox-Turnbull, Wendy

    2010-01-01

    This article investigates recent literature in the area of classroom conversation and dialogue with the aim of gaining a better understanding of the role that classroom conversation and dialogue plays in learning. It also investigates literature on the constructivist, collaborative nature of technology education and suggests that to enhance our…

  9. 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...

  10. Integrating Technology in STEM Education

    Directory of Open Access Journals (Sweden)

    Priya Chacko

    2015-03-01

    Full Text Available Students have access to the Internet at their fingertips via e-tablets and smart phones. However, the STEM fields are struggling to remain relevant in students’ lives outside the classroom. In an effort to improve high school science curricula and to keep students engaged in the classroom, we developed a technology-rich bioengineering summer program for high school students in grades 9-12. The program utilized touch screen technology in conjunction with hands-on experiments and traditional lecturing to create an entertaining, relevant, and effective classroom experience.

  11. 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

  12. Stem cell technology for neurodegenerative diseases.

    Science.gov (United States)

    Lunn, J Simon; Sakowski, Stacey A; Hur, Junguk; Feldman, Eva L

    2011-09-01

    Over the past 20 years, stem cell technologies have become an increasingly attractive option to investigate and treat neurodegenerative diseases. In the current review, we discuss the process of extending basic stem cell research into translational therapies for patients suffering from neurodegenerative diseases. We begin with a discussion of the burden of these diseases on society, emphasizing the need for increased attention toward advancing stem cell therapies. We then explain the various types of stem cells utilized in neurodegenerative disease research, and outline important issues to consider in the transition of stem cell therapy from bench to bedside. Finally, we detail the current progress regarding the applications of stem cell therapies to specific neurodegenerative diseases, focusing on Parkinson disease, Huntington disease, Alzheimer disease, amyotrophic lateral sclerosis, and spinal muscular atrophy. With a greater understanding of the capacity of stem cell technologies, there is growing public hope that stem cell therapies will continue to progress into realistic and efficacious treatments for neurodegenerative diseases.

  13. Polymer microarray technology for stem cell engineering.

    Science.gov (United States)

    Coyle, Robert; Jia, Jia; Mei, Ying

    2016-04-01

    Stem cells hold remarkable promise for applications in tissue engineering and disease modeling. During the past decade, significant progress has been made in developing soluble factors (e.g., small molecules and growth factors) to direct stem cells into a desired phenotype. However, the current lack of suitable synthetic materials to regulate stem cell activity has limited the realization of the enormous potential of stem cells. This can be attributed to a large number of materials properties (e.g., chemical structures and physical properties of materials) that can affect stem cell fate. This makes it challenging to design biomaterials to direct stem cell behavior. To address this, polymer microarray technology has been developed to rapidly identify materials for a variety of stem cell applications. In this article, we summarize recent developments in polymer array technology and their applications in stem cell engineering. Stem cells hold remarkable promise for applications in tissue engineering and disease modeling. In the last decade, significant progress has been made in developing chemically defined media to direct stem cells into a desired phenotype. However, the current lack of the suitable synthetic materials to regulate stem cell activities has been limiting the realization of the potential of stem cells. This can be attributed to the number of variables in material properties (e.g., chemical structures and physical properties) that can affect stem cells. Polymer microarray technology has shown to be a powerful tool to rapidly identify materials for a variety of stem cell applications. Here we summarize recent developments in polymer array technology and their applications in stem cell engineering. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  14. 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.

  15. STEM: Science Technology Engineering Mathematics. Executive Summary

    Science.gov (United States)

    Carnevale, Anthony P.; Smith, Nicole; Melton, Michelle

    2011-01-01

    Science, Technology, Engineering, and Mathematics (STEM) occupations are critical to the nation's continued economic competitiveness because of their direct ties to innovation, economic growth, and productivity, even though they will only be 5 percent of all jobs in the U.S. economy by 2018. The disproportionate influence of STEM raises a…

  16. Conversational Knowledge Process for Social Technology

    Science.gov (United States)

    Nishida, Toyoaki

    The conversational knowledge process is a collective activity for knowledge creation, management, and application where conversational communications are used as a primary means of interaction among participating actors. In this article, I survey a suite of communication tools that augment the conversational knowledge process in order to accelerate social problem solving.

  17. 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…

  18. Solar to fuels conversion technologies: a perspective.

    Science.gov (United States)

    Tuller, Harry L

    2017-01-01

    To meet increasing energy needs, while limiting greenhouse gas emissions over the coming decades, power capacity on a large scale will need to be provided from renewable sources, with solar expected to play a central role. While the focus to date has been on electricity generation via photovoltaic (PV) cells, electricity production currently accounts for only about one-third of total primary energy consumption. As a consequence, solar-to-fuel conversion will need to play an increasingly important role and, thereby, satisfy the need to replace high energy density fossil fuels with cleaner alternatives that remain easy to transport and store. The solar refinery concept (Herron et al. in Energy Environ Sci 8:126-157, 2015), in which captured solar radiation provides energy in the form of heat, electricity or photons, used to convert the basic chemical feedstocks CO2 and H2O into fuels, is reviewed as are the key conversion processes based on (1) combined PV and electrolysis, (2) photoelectrochemically driven electrolysis and (3) thermochemical processes, all focused on initially converting H2O and CO2 to H2 and CO. Recent advances, as well as remaining challenges, associated with solar-to-fuel conversion are discussed, as is the need for an intensive research and development effort to bring such processes to scale.

  19. 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.

  20. 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

  1. 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.

  2. Emerging electrochemical energy conversion and storage technologies

    Directory of Open Access Journals (Sweden)

    Sukhvinder P.S. BADWAL

    2014-09-01

    Full Text Available 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.

  3. Emerging electrochemical energy conversion and storage technologies

    Science.gov (United States)

    Badwal, Sukhvinder; Giddey, Sarbjit; Munnings, Christopher; Bhatt, Anand; Hollenkamp, Tony

    2014-09-01

    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.

  4. Metallurgical technologies, energy conversion, and magnetohydrodynamic flows

    Energy Technology Data Exchange (ETDEWEB)

    Branover, H.; Unger, Y.

    1993-01-01

    The present volume discusses metallurgical applications of MHD, R D on MHD devices employing liquid working medium for process applications, electromagnetic (EM) modulation of molten metal flow, EM pump performance of superconducting MHD devices, induction EM alkali-metal pumps, a physical model for EM-driven flow in channel-induction furnaces, grain refinement in Al alloys via EM vibrational method, dendrite growth of solidifying metal in dc magnetic field, MHD for mass and heat transfer in single-crystal melt growth, inverse EM shaping, and liquid-metal MHD development in Israel. Also discussed are the embrittlement of steel by lead, an open cycle MHD disk generator, the acceleration of gas-liquid piston flows for molten-metal MHD generators, MHD flow around a cylinder, new MHD drag coefficients, liquid-metal MHD two-phase flow, and two-phase liquid gas mixers for MHD energy conversion.

  5. 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.

  6. 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…

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

    Science.gov (United States)

    Snoeckx, Ramses; Bogaerts, Annemie

    2017-08-21

    CO2 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 CO2 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 CO2 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 CO2 conversion, as well as the future challenges for its practical implementation.

  8. 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.

  9. 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.

  10. 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.

  11. STEM: Science Technology Engineering Mathematics. State-Level Analysis

    Science.gov (United States)

    Carnevale, Anthony P.; Smith, Nicole; Melton, Michelle

    2011-01-01

    The science, technology, engineering, and mathematics (STEM) state-level analysis provides policymakers, educators, state government officials, and others with details on the projections of STEM jobs through 2018. This report delivers a state-by-state snapshot of the demand for STEM jobs, including: (1) The number of forecast net new and…

  12. Science, Technology, Engineering, Mathematics (STEM): Catalyzing Change Amid the Confusion

    Science.gov (United States)

    Barakos, Lynn; Lujan, Vanessa; Strang, Craig

    2012-01-01

    Over the past eight years or so, educators have struggled to make sense of the many views and definitions of science, technology, engineering, and mathematics (STEM) education and what constitutes quality in STEM practices. The multitude of recent STEM funding opportunities has done little to create a common understanding about how to best engage…

  13. Key Issue: Recruiting Science, Technology, Engineering, and Mathematics (STEM) Teachers

    Science.gov (United States)

    McGraner, Kristin L.

    2009-01-01

    A STEM teacher is one who teaches in the fields of science, technology, engineering, and mathematics. In K-12 schooling, most STEM teachers instruct mathematics and science classes, which continue to be critical shortage areas. As part of a comprehensive human capital strategy, designing recruitment initiatives to attract qualified STEM teachers…

  14. Thermoelectric Energy Conversion: Future Directions and Technology Development Needs

    Science.gov (United States)

    Fleurial, Jean-Pierre

    2007-01-01

    This viewgraph presentation reviews the process of thermoelectric energy conversion along with key technology needs and challenges. The topics include: 1) The Case for Thermoelectrics; 2) Advances in Thermoelectrics: Investment Needed; 3) Current U.S. Investment (FY07); 4) Increasing Thermoelectric Materials Conversion Efficiency Key Science Needs and Challenges; 5) Developing Advanced TE Components & Systems Key Technology Needs and Challenges; 6) Thermoelectrics; 7) 200W Class Lightweight Portable Thermoelectric Generator; 8) Hybrid Absorption Cooling/TE Power Cogeneration System; 9) Major Opportunities in Energy Industry; 10) Automobile Waste Heat Recovery; 11) Thermoelectrics at JPL; 12) Recent Advances at JPL in Thermoelectric Converter Component Technologies; 13) Thermoelectrics Background on Power Generation and Cooling Operational Modes; 14) Thermoelectric Power Generation; and 15) Thermoelectric Cooling.

  15. Science and society: a stem cell technology model.

    Science.gov (United States)

    Kiatpongsan, Sorapop

    2008-02-01

    Stem cell technology has been recognized as an emerging technology that could transform current supportive approach toward curing many chronic disorders and degenerative conditions. Regenerative medicine is the promising area of medical practice in the coming decade. However, stem cell technology also brings up controversial issues from the bioethical perspective such as the destruction of human embryos to derive embryonic stem cells or putting the egg donors at risk when retrieving oocytes used in somatic cell nuclear transfer technique. Recently, scientists have discovered a novel method to derive human embryonic stem cell-like cells (iPS; induced pluripotent stem cells) from human skin cells. This innovative approach would not only be a breakthrough discovery to advance the knowledge of stem cell research and the landmark for future stem cell-based therapy but will also provide viable solutions for social concerns on bioethical issues.

  16. Technology-Conversant Management Education: Introducing A New Discipline

    Directory of Open Access Journals (Sweden)

    Van Wyk, Rias Johann

    2014-05-01

    Full Text Available In the first quarter of 2013, the Department of Industrial Engineering at the University of Stellenbosch launched a new academic course, Strategic Technology Analysis (STA, as an elective in its M.Sc. in Engineering Management and M.Eng. Industrial Engineering degrees. STA views technology as a knowledge area in its own right, focuses on the inherent characteristics of technology, and explores its natural order. The purpose was to ascertain whether a course of this nature, which offered the outline for a new academic discipline, would be of benefit to a technology-conversant management programme. The course was well-received. It encouraged a greater awareness of technological positioning i.e., aligning overall corporate strategy with new opportunities across the entire technological frontier. This article describes the background to this initiative, the history of STA, its inherent structure, and its role in professional practice. It then looks ahead at the possible dissemination of this knowledge into different settings where technology-conversant management is taught.

  17. 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.

  18. 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…

  19. 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.

  20. 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

    The composition of wheat straw leaf and stem fractions were characterized using traditional strong acid hydrolysis, and monoclonal antibodies using comprehensive microarray polymer profiling (CoMPP). These results are then related to high throughput lignocellulose pretreatment and saccharification....... 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...... 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...

  1. New Advanced Technologies in Stem Cell Therapy

    Science.gov (United States)

    2013-09-01

    Stem Cells and Development , vol. 21, no. 8, pp. 1299–1308, 2012. [25] B. Zheng, B...Matsumoto, H. Eto et al., “Functional implications of CD34 expression in human adipose-derived stem/progenitor cells,” Stem Cells and Development , vol...and progenitor cells within adipose tissue,” Stem Cells and Development , vol. 17, no. 6, pp. 1053–1063, 2008. [43] H. Li, L. Zimmerlin, K. G. Marra,

  2. 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.

  3. Direct conversion technology: Annual summary report CY 1988

    Energy Technology Data Exchange (ETDEWEB)

    Massier, P.F.; Bankston, C.P.; Fabris, G.; Kirol, L.D.

    1988-12-01

    The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct thermal-to-electric energy conversion systems that have potential application for energy conservation in the end-use sectors. This report contains progress of research on the Alkali Metal Thermal-to-Electric Converter (AMTEC), and on the Two-Phase Liquid-Metal MHD Electrical Generator (LMMHD) for the period January 1988 through December 1988. Research on these concepts was initiated during October 1987. In addition, status reviews and assessments are presented for thermomagnetic converter concepts and for thermoelastic converters (Nitinol heat engines). Reports prepared on previous occasions contain discussions on the following other direct conversion concepts: thermoelectric, pyroelectric, thermionic thermophotovoltaic and thermoacoustic; and also, more complete discussions of AMTEC and LMMHD systems. A tabulated summary of the various systems which have been reviewed thus far has been prepared. Some of the important technical research needs are listed and a schematic of each system is shown. These tabulations are included herein as figures. 43 refs., 26 figs., 1 tab.

  4. Women of Color in Science, Technology, Engineering, and Mathematics (STEM)

    Science.gov (United States)

    Johnson, Dawn R.

    2011-01-01

    Scholars have theorized and examined women's underrepresentation in science, technology, engineering and mathematics (STEM) fields for well over thirty years. However, much of this research has paid little attention to issues of racial and ethnic diversity among women, suggesting that all women have the same experiences in STEM. Women of color…

  5. Life cycle impact assessment of various waste conversion technologies.

    Science.gov (United States)

    Khoo, Hsien H

    2009-06-01

    Advanced thermal treatment technologies utilizing pyrolysis or gasification, as well as a combined approach, are introduced as sustainable methods to treat wastes in Singapore. Eight different technologies are evaluated: pyrolysis-gasification of MSW; pyrolysis of MSW; thermal cracking gasification of granulated MSW; combined pyrolysis, gasification and oxidation of MSW; steam gasification of wood; circulating fluidized bed (CFB) gasification of organic wastes; gasification of RDF; and the gasification of tyres. Life cycle assessment is carried out to determine the environmental impacts of the various waste conversion systems including global warming potential, acidification potential, terrestrial eutrophication and ozone photochemical formation. The normalization and weighting results, calculated according to Singapore national emission inventories, showed that the two highest impacts are from thermal cracking gasification of granulated MSW and the gasification of RDF; and the least are from the steam gasification of wood and the pyrolysis-gasification of MSW. A simplified life cycle cost comparison showed that the two most costs-effective waste conversion systems are the CFB gasification of organic waste and the combined pyrolysis, gasification and oxidation of MSW. The least favorable - highest environmental impact as well as highest costs - are the thermal cracking gasification of granulated MSW and the gasification of tyres.

  6. Stem Cells in Skeletal Tissue Engineering: Technologies and Models

    Science.gov (United States)

    Langhans, Mark T.; Yu, Shuting; Tuan, Rocky S.

    2017-01-01

    This review surveys the use of pluripotent and multipotent stem cells in skeletal tissue engineering. Specific emphasis is focused on evaluating the function and activities of these cells in the context of development in vivo, and how technologies and methods of stem cell-based tissue engineering for stem cells must draw inspiration from developmental biology. Information on the embryonic origin and in vivo differentiation of skeletal tissues is first reviewed, to shed light on the persistence and activities of adult stem cells that remain in skeletal tissues after embryogenesis. Next, the development and differentiation of pluripotent stem cells is discussed, and some of their advantages and disadvantages in the context of tissue engineering is presented. The final section highlights current use of multipotent adult mesenchymal stem cells, reviewing their origin, differentiation capacity, and potential applications to tissue engineering. PMID:26423296

  7. New Advanced Technologies in Stem Cell Therapy

    Science.gov (United States)

    2014-11-01

    bacterial products, viruses, growth factors, and oxidative stress, the complex is activated. Activated IKKβ phosphorylates IkB, leading to its...eye may prove more straightforward targets for cell ther- apy. Loss of the retinal pigment epithelium (RPE) in age-related macular degeneration has...Buchholz et al., Rapid and efficient directed differentiation of human pluripotent stem cells into retinal pigmented epithelium. Stem Cells Transl. Med. 2

  8. Discrimination of Stem Cell Status after Subjecting Cynomolgus Monkey Pluripotent Stem Cells to Naïve Conversion

    Science.gov (United States)

    Honda, Arata; Kawano, Yoshihiro; Izu, Haruna; Choijookhuu, Narantsog; Honsho, Kimiko; Nakamura, Tomonori; Yabuta, Yukihiro; Yamamoto, Takuya; Takashima, Yasuhiro; Hirose, Michiko; Sankai, Tadashi; Hishikawa, Yoshitaka; Ogura, Atsuo; Saitou, Mitinori

    2017-01-01

    Experimental animal models have played an indispensable role in the development of human induced pluripotent stem cell (iPSC) research. The derivation of high-quality (so-called “true naïve state”) iPSCs of non-human primates enhances their application and safety for human regenerative medicine. Although several attempts have been made to convert human and non-human primate PSCs into a truly naïve state, it is unclear which evaluation methods can discriminate them as being truly naïve. Here we attempted to derive naïve cynomolgus monkey (Cm) (Macaca fascicularis) embryonic stem cells (ESCs) and iPSCs. Several characteristics of naïve Cm ESCs including colony morphology, appearance of naïve-related mRNAs and proteins, leukaemia inhibitory factor dependency, and mitochondrial respiration were confirmed. Next, we generated Cm iPSCs and converted them to a naïve state. Transcriptomic comparison of PSCs with early Cm embryos elucidated the partial achievement (termed naïve-like) of their conversion. When these were subjected to in vitro neural differentiation, enhanced differentiating capacities were observed after naïve-like conversion, but some lines exhibited heterogeneity. The difficulty of achieving contribution to chimeric mouse embryos was also demonstrated. These results suggest that Cm PSCs could ameliorate their in vitro neural differentiation potential even though they could not display true naïve characteristics. PMID:28349944

  9. 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.

  10. Advanced Energy Conversion Technologies and Architectures for Earth and Beyond

    Science.gov (United States)

    Howell, Joe T.; Fikes, John C.; Phillips, Dane J.; Laycock, Rustin L.; ONeill, Mark; Henley, Mark W.; Fork, Richard L.

    2006-01-01

    Research, development and studies of novel space-based solar power systems, technologies and architectures for Earth and beyond are needed to reduce the cost of clean electrical power for terrestrial use and to provide a stepping stone for providing an abundance of power in space, i.e., manufacturing facilities, tourist facilities, delivery of power between objects in space, and between space and surface sites. The architectures, technologies and systems needed for space to Earth applications may also be used for in-space applications. Advances in key technologies, i.e., power generation, power management and distribution, power beaming and conversion of beamed power are needed to achieve the objectives of both terrestrial and extraterrestrial applications. There is a need to produce "proof-ofconcept" validation of critical WPT technologies for both the near-term, as well as far-term applications. Investments may be harvested in near-term beam safe demonstrations of commercial WPT applications. Receiving sites (users) include ground-based stations for terrestrial electrical power, orbital sites to provide power for satellites and other platforms, future space elevator systems, space vehicle propulsion, and space surface sites. Space surface receiving sites of particular interest include the areas of permanent shadow near the moon s North and South poles, where WPT technologies could enable access to ice and other useful resources for human exploration. This paper discusses work addressing a promising approach to solar power generation and beamed power conversion. The approach is based on a unique high-power solar concentrator array called Stretched Lens Array (SLA) applied to both solar power generation and beamed power conversion. Since both versions (solar and laser) of SLA use many identical components (only the photovoltaic cells need to be different), economies of manufacturing and scale may be realized by using SLA on both ends of the laser power beaming

  11. Highly Efficient Neural Conversion of Human Pluripotent Stem Cells in Adherent and Animal-Free Conditions.

    Science.gov (United States)

    Lukovic, Dunja; Diez Lloret, Andrea; Stojkovic, Petra; Rodríguez-Martínez, Daniel; Perez Arago, Maria Amparo; Rodriguez-Jimenez, Francisco Javier; González-Rodríguez, Patricia; López-Barneo, José; Sykova, Eva; Jendelova, Pavla; Kostic, Jelena; Moreno-Manzano, Victoria; Stojkovic, Miodrag; Bhattacharya, Shomi S; Erceg, Slaven

    2017-04-01

    Neural differentiation of human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) can produce a valuable and robust source of human neural cell subtypes, holding great promise for the study of neurogenesis and development, and for treating neurological diseases. However, current hESCs and hiPSCs neural differentiation protocols require either animal factors or embryoid body formation, which decreases efficiency and yield, and strongly limits medical applications. Here we develop a simple, animal-free protocol for neural conversion of both hESCs and hiPSCs in adherent culture conditions. A simple medium formula including insulin induces the direct conversion of >98% of hESCs and hiPSCs into expandable, transplantable, and functional neural progenitors with neural rosette characteristics. Further differentiation of neural progenitors into dopaminergic and spinal motoneurons as well as astrocytes and oligodendrocytes indicates that these neural progenitors retain responsiveness to instructive cues revealing the robust applicability of the protocol in the treatment of different neurodegenerative diseases. The fact that this protocol includes animal-free medium and human extracellular matrix components avoiding embryoid bodies makes this protocol suitable for the use in clinic. Stem Cells Translational Medicine 2017;6:1217-1226.

  12. 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…

  13. Direct conversion of root primordium into shoot meristem relies on timing of stem cell niche development.

    Science.gov (United States)

    Rosspopoff, Olga; Chelysheva, Liudmila; Saffar, Julie; Lecorgne, Lena; Gey, Delphine; Caillieux, Erwann; Colot, Vincent; Roudier, François; Hilson, Pierre; Berthomé, Richard; Da Costa, Marco; Rech, Philippe

    2017-04-01

    To understand how the identity of an organ can be switched, we studied the transformation of lateral root primordia (LRP) into shoot meristems in Arabidopsis root segments. In this system, the cytokinin-induced conversion does not involve the formation of callus-like structures. Detailed analysis showed that the conversion sequence starts with a mitotic pause and is concomitant with the differential expression of regulators of root and shoot development. The conversion requires the presence of apical stem cells, and only LRP at stages VI or VII can be switched. It is engaged as soon as cell divisions resume because their position and orientation differ in the converting organ compared with the undisturbed emerging LRP. By alternating auxin and cytokinin treatments, we showed that the root and shoot organogenetic programs are remarkably plastic, as the status of the same plant stem cell niche can be reversed repeatedly within a set developmental window. Thus, the networks at play in the meristem of a root can morph in the span of a couple of cell division cycles into those of a shoot, and back, through transdifferentiation. © 2017. Published by The Company of Biologists Ltd.

  14. 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.

  15. 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.

  16. 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

  17. 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.

  18. Stream conversion technology and gas condensate field development

    Energy Technology Data Exchange (ETDEWEB)

    Kuntadi, Arif

    2012-07-01

    In the last few years, integrated modeling has become a preferred tool in the petroleum industry to manage the value chain of different assets. It is slowly replacing the traditional modeling approach that treats each petroleum asset model separately. Having different discipline models and applications in a single platform will ensure more consistency of the value chain from one asset to another. Integrated modeling also enables engineers to optimize assets, both locally and globally, using an automatic approach. Coupling of different petroleum assets entails transferring and combining petroleum streams from one asset to the others. Stream conversion is a key requirement in integrated modeling because petroleum assets usually have their own fluid model, and it is rare to have a single common fluid model in both the subsurface and surface simulation models. This thesis investigates different stream conversion methods and provides important technologies for integrating different petroleum assets into an integrated asset model. These stream conversions are expected to have highly accurate results and reduce the computational time. Reservoir engineers have utilized both compositional and black-oil reservoir simulations for many years. Due to the CPU-time consideration, the EOS model used in a compositional simulation is normally limited to 6-10 components, a so-called lumped EOS model. We propose a delumping method to generate detailed compositional streams from either black-oil or compositional (lumped-EOS) reservoir simulations, performed as a simple post-processing step. These methods are based on a set of phase-specific and pressure-dependent split factors. The reservoir simulation phase behavior can be approximated by a PVT depletion experiment, such as the CCE depletion experiment. We have used this approach to develop the blackoil and compositional delumping method applied to the reservoir simulation output. The split factors are generated from simulated

  19. ECUT (Energy Conversion and Utilization Technologies Program). Biocatalysis Project

    Science.gov (United States)

    1986-01-01

    Presented are the FY 1985 accomplishments, activities, and planned research efforts of the Biocatalysis Project of the U.S. Department of Energy, Energy Conversion and Utilization Technologies (ECUT) Program. The Project's technical activities were organized as follows: In the Molecular Modeling and Applied Genetics work element, research focused on (1) modeling and simulation studies to establish the physiological basis of high temperature tolerance in a selected enzyme and the catalytic mechanisms of three species of another enzyme, and (2) determining the degree of plasmid amplification and stability of several DNA bacterial strains. In the Bioprocess Engineering work element, research focused on (1) studies of plasmid propagation and the generation of models, (2) developing methods for preparing immobilized biocatalyst beads, and (3) developing an enzyme encapsulation method. In the Process Design and Analysis work element, research focused on (1) further refinement of a test case simulation of the economics and energy efficiency of alternative biocatalyzed production processes, (2) developing a candidate bioprocess to determine the potential for reduced energy consumption and facility/operating costs, and (3) a techno-economic assessment of potential advancements in microbial ammonia production.

  20. Cancer Stem Cell Biomarker Discovery Using Antibody Array Technology.

    Science.gov (United States)

    Burgess, Rob; Huang, Ruo-Pan

    2016-01-01

    Cancer is a complex disease involving hundreds of pathways and numerous levels of disease progression. In addition, there is a growing body of evidence that the origins and growth rates of specific types of cancer may involve "cancer stem cells," which are defined as "cells within a tumor that possess the capacity to self-renew and to cause the development of heterogeneous lineages of cancer cells that comprise the tumor.(1)" Many types of cancer are now thought to harbor cancer stem cells. These cells themselves are thought to be unique in comparison to other cells types present within the tumor and to exhibit characteristics that allow for the promotion of tumorigenesis and in some cases metastasis. In addition, it is speculated that each type of cancer stem cell exhibits a unique set of molecular and biochemical markers. These markers, alone or in combination, may act as a signature for defining not only the type of cancer but also the progressive state. These biomarkers may also double as signaling entities which act autonomously or upon neighboring cancer stem cells or other cells within the local microenvironment to promote tumorigenesis. This review describes the heterogeneic properties of cancer stem cells and outlines the identification and application of biomarkers and signaling molecules defining these cells as they relate to different forms of cancer. Other examples of biomarkers and signaling molecules expressed by neighboring cells in the local tumor microenvironment are also discussed. In addition, biochemical signatures for cancer stem cell autocrine/paracrine signaling, local site recruitment, tumorigenic potential, and conversion to a stem-like phenotype are described.

  1. Lab-on-a-chip technologies for stem cell analysis.

    Science.gov (United States)

    Ertl, Peter; Sticker, Drago; Charwat, Verena; Kasper, Cornelia; Lepperdinger, Günter

    2014-05-01

    The combination of microfabrication-based technologies with cell biology has laid the foundation for the development of advanced in vitro diagnostic systems capable of analyzing cell cultures under physiologically relevant conditions. In the present review, we address recent lab-on-a-chip developments for stem cell analysis. We highlight in particular the tangible advantages of microfluidic devices to overcome most of the challenges associated with stem cell identification, expansion and differentiation, with the greatest advantage being that lab-on-a-chip technology allows for the precise regulation of culturing conditions, while simultaneously monitoring relevant parameters using embedded sensory systems. State-of-the-art lab-on-a-chip platforms for in vitro assessment of stem cell cultures are presented and their potential future applications discussed.

  2. [Stem cell research and science and technology policy in Japan].

    Science.gov (United States)

    Yashiro, Yoshimi

    2011-12-01

    In this paper I review the present condition of the regeneration medicine research using pluripotency and a somatic stem cell, and I describe the subject of the science and technology policy in Japan towards realization of regeneration medicine. The Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) supported research promotion by the prompt action in 2007 when establishment of the iPS cell was reported by Shinya Yamanaka. Although the hospitable support of the Japanese government to an iPS cell is continued still now, there are some problems in respect of the support to other stem cell researches, and industrialization of regeneration medicine. In order to win a place in highly competitive area of investigation, MEXT needs to change policy so that funds may be widely supplied also to stem cell researches other than iPS cell research.

  3. Gene targeting in embryonic stem cells, II: conditional technologies

    Science.gov (United States)

    Genome modification via transgenesis has allowed researchers to link genotype and phenotype as an alternative approach to the characterization of random mutations through evolution. The synergy of technologies from the fields of embryonic stem (ES) cells, gene knockouts, and protein-mediated recombi...

  4. 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 fun...

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

    Science.gov (United States)

    Focosi, Daniele; Pistello, Mauro

    2016-03-01

    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.

  6. LIN28 Regulates Stem Cell Metabolism and Conversion to Primed Pluripotency.

    Science.gov (United States)

    Zhang, Jin; Ratanasirintrawoot, Sutheera; Chandrasekaran, Sriram; Wu, Zhaoting; Ficarro, Scott B; Yu, Chunxiao; Ross, Christian A; Cacchiarelli, Davide; Xia, Qing; Seligson, Marc; Shinoda, Gen; Xie, Wen; Cahan, Patrick; Wang, Longfei; Ng, Shyh-Chang; Tintara, Supisara; Trapnell, Cole; Onder, Tamer; Loh, Yuin-Han; Mikkelsen, Tarjei; Sliz, Piotr; Teitell, Michael A; Asara, John M; Marto, Jarrod A; Li, Hu; Collins, James J; Daley, George Q

    2016-07-07

    The RNA-binding proteins LIN28A and LIN28B play critical roles in embryonic development, tumorigenesis, and pluripotency, but their exact functions are poorly understood. Here, we show that, like LIN28A, LIN28B can function effectively with NANOG, OCT4, and SOX2 in reprogramming to pluripotency and that reactivation of both endogenous LIN28A and LIN28B loci are required for maximal reprogramming efficiency. In human fibroblasts, LIN28B is activated early during reprogramming, while LIN28A is activated later during the transition to bona fide induced pluripotent stem cells (iPSCs). In murine cells, LIN28A and LIN28B facilitate conversion from naive to primed pluripotency. Proteomic and metabolomic analysis highlighted roles for LIN28 in maintaining the low mitochondrial function associated with primed pluripotency and in regulating one-carbon metabolism, nucleotide metabolism, and histone methylation. LIN28 binds to mRNAs of proteins important for oxidative phosphorylation and modulates protein abundance. Thus, LIN28A and LIN28B play cooperative roles in regulating reprogramming, naive/primed pluripotency, and stem cell metabolism. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. 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.

  8. 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…

  9. Induced Pluripotent Stem Cell Technology in Regenerative Medicine and Biology

    Science.gov (United States)

    Pei, Duanqing; Xu, Jianyong; Zhuang, Qiang; Tse, Hung-Fat; Esteban, Miguel A.

    The potential of human embryonic stem cells (ESCs) for regenerative medicine is unquestionable, but practical and ethical considerations have hampered clinical application and research. In an attempt to overcome these issues, the conversion of somatic cells into pluripotent stem cells similar to ESCs, commonly termed nuclear reprogramming, has been a top objective of contemporary biology. More than 40 years ago, King, Briggs, and Gurdon pioneered somatic cell nuclear reprogramming in frogs, and in 1981 Evans successfully isolated mouse ESCs. In 1997 Wilmut and collaborators produced the first cloned mammal using nuclear transfer, and then Thomson obtained human ESCs from in vitro fertilized blastocysts in 1998. Over the last 2 decades we have also seen remarkable findings regarding how ESC behavior is controlled, the importance of which should not be underestimated. This knowledge allowed the laboratory of Shinya Yamanaka to overcome brilliantly conceptual and technical barriers in 2006 and generate induced pluripotent stem cells (iPSCs) from mouse fibroblasts by overexpressing defined combinations of ESC-enriched transcription factors. Here, we discuss some important implications of human iPSCs for biology and medicine and also point to possible future directions.

  10. Progress Report on Coordinating Federal Science, Technology, Engineering, and Mathematics (STEM) Education

    Science.gov (United States)

    Executive Office of the President, 2016

    2016-01-01

    As called for in the America COMPETES Reauthorization Act of 2010, the National Science and Technology Council's (NSTC) Committee on STEM Education (CoSTEM) released, in May of 2013, the Federal Science, Technology, Engineering, and Mathematics (STEM) Education 5- Year Strategic Plan (Strategic Plan). As required by the Act, this report includes…

  11. 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.…

  12. 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...... conversion processes with other systems including coexisting infrastructure and carbon dioxide sources is described.Then, the importance of PSE based studies for such application is discussed. Finally, some perspectives on the status and future directions of carbon dioxide conversion technology...

  13. 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.

  14. 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.

  15. Design requirements for interfaces in solar energy conversion technologies

    Science.gov (United States)

    Butler, B. L.

    1982-04-01

    Candidate materials for improving the durability and economics of solar energy conversion systems (SECS) are reviewed. A 30-yr lifetime is regarded as necessary for solar collector and concentrator materials in order to offset the high initial costs of SECS in parabolic dish, heliostat, parabolic trough, flat plate collector, OTEC, solar cell, and wind turbine configurations. The materials are required to transfer a maximum amount of intercepted energy without degrading from exposure to UV radiation, wind, water, dust, and temperature cycling. Glass and mirrored surfaces for reflecting or refracting optical subsystems are currently made from soda-lime, boro- and aluminosilicate, and must resist chemicals, abrasion, and permeability, and have good strength, flexibility, coefficient of expansion, and Young's modulus. Additional concerns are present in photochemical, solar cell, and in substrata components and systems.

  16. Advanced Electric Distribution, Switching, and Conversion Technology for Power Control

    Science.gov (United States)

    Soltis, James V.

    1998-01-01

    The Electrical Power Control Unit currently under development by Sundstrand Aerospace for use on the Fluids Combustion Facility of the International Space Station is the precursor of modular power distribution and conversion concepts for future spacecraft and aircraft applications. This unit combines modular current-limiting flexible remote power controllers and paralleled power converters into one package. Each unit includes three 1-kW, current-limiting power converter modules designed for a variable-ratio load sharing capability. The flexible remote power controllers can be used in parallel to match load requirements and can be programmed for an initial ON or OFF state on powerup. The unit contains an integral cold plate. The modularity and hybridization of the Electrical Power Control Unit sets the course for future spacecraft electrical power systems, both large and small. In such systems, the basic hybridized converter and flexible remote power controller building blocks could be configured to match power distribution and conversion capabilities to load requirements. In addition, the flexible remote power controllers could be configured in assemblies to feed multiple individual loads and could be used in parallel to meet the specific current requirements of each of those loads. Ultimately, the Electrical Power Control Unit design concept could evolve to a common switch module hybrid, or family of hybrids, for both converter and switchgear applications. By assembling hybrids of a common current rating and voltage class in parallel, researchers could readily adapt these units for multiple applications. The Electrical Power Control Unit concept has the potential to be scaled to larger and smaller ratings for both small and large spacecraft and for aircraft where high-power density, remote power controllers or power converters are required and a common replacement part is desired for multiples of a base current rating.

  17. 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.

  18. The Long Conversation Maximizing Business Value from Information Technology Investment

    CERN Document Server

    Lorenzo, Oswaldo; González, Gastón; Ramdani, Boumediene

    2011-01-01

    For many years companies have been investing in enterprise systems and IT initiatives but they are now struggling to achieve the desired results. It takes a long time to make the best of your enterprise systems so businesses must stop looking for the next technology 'silver bullet' and instead maximize the value of existing IT investments.

  19. Induced pluripotent stem cell technology and aquatic animal species.

    Science.gov (United States)

    Temkin, Alexis M; Spyropoulos, Demetri D

    2014-06-01

    Aquatic animal species are the overall leaders in the scientific investigation of tough but important global health issues, including environmental toxicants and climate change. Historically, aquatic animal species also stand at the forefront of experimental biology, embryology and stem cell research. Over the past decade, intensive and high-powered investigations principally involving mouse and human cells have brought the generation and study of induced pluripotent stem cells (iPSCs) to a level that facilitates widespread use in a spectrum of species. A review of key features of these investigations is presented here as a primer for the use of iPSC technology to enhance ongoing aquatic animal species studies. iPSC and other cutting edge technologies create the potential to study individuals from "the wild" closer to the level of investigation applied to sophisticated inbred mouse models. A wide variety of surveys and hypothesis-driven investigations can be envisioned using this new capability, including comparisons of organism-specific development and exposure response and the testing of fundamental dogmas established using inbred mice. However, with these new capabilities, also come new criteria for rigorous baseline assessments and testing. Both the methods for inducing pluripotency and the source material can negatively impact iPSC quality and bourgeoning applications. Therefore, more rigorous strategies not required for inbred mouse models will have to be implemented to approach global health issues using individuals from "the wild" for aquatic animal species. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. 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.

  1. Development of an Instrument to Assess Attitudes toward Science, Technology, Engineering, and Mathematics (STEM)

    Science.gov (United States)

    Guzey, S. Selcen; Harwell, Michael; Moore, Tamara

    2014-01-01

    There is a need for more students to be interested in science, technology, engineering, and mathematics (STEM) careers to advance U.S. competitiveness and economic growth. A consensus exists that improving STEM education is necessary for motivating more students to pursue STEM careers. In this study, a survey to measure student (grades 4-6)…

  2. Thermoelectric Energy Conversion Technology for High-Altitude Airships

    Science.gov (United States)

    Choi, Sang H.; Elliott, James R.; King, Glen C.; Park, Yeonjoon; Kim, Jae-Woo; Chu, Sang-Hyon

    2011-01-01

    The High Altitude Airship (HAA) has various application potential and mission scenarios that require onboard energy harvesting and power distribution systems. The power technology for HAA maneuverability and mission-oriented applications must come from its surroundings, e.g. solar power. The energy harvesting system considered for HAA is based on the advanced thermoelectric (ATE) materials being developed at NASA Langley Research Center. The materials selected for ATE are silicon germanium (SiGe) and bismuth telluride (Bi2Te3), in multiple layers. The layered structure of the advanced TE materials is specifically engineered to provide maximum efficiency for the corresponding range of operational temperatures. For three layers of the advanced TE materials that operate at high, medium, and low temperatures, correspondingly in a tandem mode, the cascaded efficiency is estimated to be greater than 60 percent.

  3. Implementing STEM technology in a Title One middle school classroom

    Science.gov (United States)

    Holcomb, Carolyn

    2013-05-01

    What do a modern day CSI forensics lab and an electron microscope have in common? It offers the ability to engage students in a scientific investigation, exploring the world of nanotechnology using modern day equipment. 7th grade students at Western Heights Middle School at Hagerstown, MD, used Hitachi's TM3000 to better understand how technology is utilized when investigating contemporary questions. Using the TM3000, students learned how to load samples, scan, take pictures, and focus the SEM. This experience was an eye opener to students who otherwise would never have had such a learning opportunity. As a result many verbalized interest in pursuing careers in STEM related fields, if only to be able to use such fun equipment. In this session the teacher will present how the instrument was used, and the lessons learned both by the instructor and her students.

  4. 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…

  5. Direct conversion technology. Annual summary report CY 1991, January 1, 1991--December 31, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Massier, P.F.; Back, L.H.; Ryan, M.A.; Fabris, G.

    1992-01-07

    The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. This report contains progress of research on the Alkali Metal Thermal-to-Electric Converter (AMTEC) and on the Two-Phase Liquid-Metal MHD Electrical Generator (LMMHD) for the period January 1, 1991 through December 31, 1991. Research on AMTEC and on LMMHD was initiated during October 1987. Reports prepared on previous occasions (Refs. 1--5) contain descriptive and performance discussions of the following direct conversion concepts: thermoelectric, pyroelectric, thermionic, thermophotovoltaic, thermoacoustic, thermomagnetic, thermoelastic (Nitionol heat engine); and also, more complete descriptive discussions of AMTEC and LMMHD systems.

  6. 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.

  7. Teachers conversations during design of technology rich curriculum activities for early literacy

    NARCIS (Netherlands)

    Boschman, Ferry; McKenney, Susan; Voogt, Joke

    2014-01-01

    Boschman, F., McKenney, S. & Voogt (2013). Teachers conversations during design of technology rich curriculum activities for early literacy. Paper presentation at the European Association for Practitioner Research on Improving Learning (EAPRIL) Annual Conference. November 27-29, Biel/Bienne, Switzer

  8. 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

  9. 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.

  10. 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.

  11. The Need for an Effective Collaboration across Science, Technology, Engineering & Mathematics (STEM) Fields for a Meaningful Technological Development in Nigeria

    Science.gov (United States)

    Haruna, Umar Ibrahim

    2015-01-01

    Collaboration plays a major role in interdisciplinary activities among Science, Technology, Engineering & Mathematics (STEM) disciplines or fields. It also affects the relationships among cluster members on the management team. Although effective collaboration does not guarantee success among STEM disciplines, its absence usually assures…

  12. Conversion of embryonic stem cells into extraembryonic lineages by CRISPR-mediated activators

    OpenAIRE

    2016-01-01

    The recently emerged CRISPR/Cas9 technique has opened a new perspective on readily editing specific genes. When combined with transcription activators, it can precisely manipulate endogenous gene expression. Here, we enhanced the expression of endogenous Cdx2 and Gata6 genes by CRISPR-mediated activators, thus mouse embryonic stem cells (ESCs) were directly converted into two extraembryonic lineages, i.e., typical trophoblast stem cells (TSCs) and extraembryonic endoderm cells (XENCs), which ...

  13. Evaluation of Various Technologies for Wave Energy Conversion in the Portuguese Nearshore

    Directory of Open Access Journals (Sweden)

    Carlos Guedes Soares

    2013-03-01

    Full Text Available The objective of the present work is to perform an evaluation of the performance provided by various technologies for wave energy conversion in the Portuguese continental coastal environment. The wave climate in the target area is first analyzed using the results from three years of simulations with a wave prediction system based on numerical models. Based on the above data, diagrams for the bivariate distributions of the sea states occurrences, defined by the significant wave height and the energy period, are designed for both winters and whole years. On this basis, the output of five different technologies for the conversion of wave energy is assessed in some relevant locations from the Portuguese nearshore. According to the results obtained, the Portuguese continental coastal environment appears to be appropriate for the wave energy extraction. At the same time, the present work shows that the output of the wave energy conversion devices does not depend only on the average wave energy but is also dependent on the distribution of the wave energy among the sea states of different periods. For this reason, a good agreement between the characteristics of the power matrices of the wave energy converters operating in a certain place and the diagrams for the bivariate distributions of the sea states occurrences corresponding to the considered location represents a key issue in selecting the most appropriate technology for wave energy conversion.

  14. Escargot Restricts Niche Cell to Stem Cell Conversion in the Drosophila Testis

    Directory of Open Access Journals (Sweden)

    Justin Voog

    2014-05-01

    Full Text Available Stem cells reside within specialized microenvironments, or niches, that control many aspects of stem cell behavior. Somatic hub cells in the Drosophila testis regulate the behavior of cyst stem cells (CySCs and germline stem cells (GSCs and are a primary component of the testis stem cell niche. The shutoff (shof mutation, characterized by premature loss of GSCs and CySCs, was mapped to a locus encoding the evolutionarily conserved transcription factor Escargot (Esg. Hub cells depleted of Esg acquire CySC characteristics and differentiate as cyst cells, resulting in complete loss of hub cells and eventually CySCs and GSCs, similar to the shof mutant phenotype. We identified Esg-interacting proteins and demonstrate an interaction between Esg and the corepressor C-terminal binding protein (CtBP, which was also required for maintenance of hub cell fate. Our results indicate that niche cells can acquire stem cell properties upon removal of a single transcription factor in vivo.

  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. 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.

  17. The Federal Science, Technology, Engineering, and Mathematics (STEM) Education Portfolio. A Report from the Federal Inventory of STEM Education Fast-Track Action Committee, Committee on STEM Education

    Science.gov (United States)

    2011-12-01

    Track Action Committee on Federal Investments in STEM Education (FI-STEM) Co-chairs Michael Feder (OSTP) Joan Ferrini-Mundy (NSF) Susan Heller...Foundation Joan Ferrini-Mundy Analytic Support Science & Technology Policy Institute Executive Office of the President Greg Gershuny (OSTP) Sarah Watson...Feder (OSTP) Department of Commerce Larry Robinson Department of Health and Human Services Dora Hughes National Aeronautics and Space

  18. Realising new health technologies: problems of regulating human stem cells in the USA.

    Science.gov (United States)

    Warren-Jones, Amanda

    2012-01-01

    Stem cell technology holds the promise of radically changing medicine through the provision of better disease models; the creation of tissue, cells, and organs for therapeutic uses; and the increased personalisation of healthcare. However, the degree to which any of these developments can be realised in the USA rests upon how effective the regulatory environment is in nurturing the technology to market. This article assesses the regulation in terms of its ability to minimise factors which erode the public interest in developing medical innovations (abuse) and promoting them to the market. This requires an overarching review of patent law (and how it fits with anti-trust and contract law); as well as the general regulation of innovation through ethical review, clinical trials, market authorisation, post-market oversight; government lead regulation of stem cells; and finally incorporating the impact of self-regulation by industry. From this assessment, it becomes possible to appreciate that the optimal system of regulation is reliant upon the gentle tweaking of many factors, rather than the wholesale revision of only a few. It also becomes possible to identify that individual tools of regulation have varying impacts. For example, the patent system may be the most open to abuse by individual companies, but as a regulatory framework it has the most mechanisms for dealing with such abuses. However, the biggest impact upon curtailing abuse derives from the self-regulation of the industry. Conversely, government led regulation is open to abuse from political agendas, but it has the greatest capacity to nurture innovation productively.

  19. CO2 conversion by plasma technology: insights from modeling the plasma chemistry and plasma reactor design

    Science.gov (United States)

    Bogaerts, A.; Berthelot, A.; Heijkers, S.; Kolev, St.; Snoeckx, R.; Sun, S.; Trenchev, G.; Van Laer, K.; Wang, W.

    2017-06-01

    In recent years there has been growing interest in the use of plasma technology for CO2 conversion. To improve this application, a good insight into the underlying mechanisms is of great importance. This can be obtained from modeling the detailed plasma chemistry in order to understand the chemical reaction pathways leading to CO2 conversion (either in pure form or mixed with another gas). Moreover, in practice, several plasma reactor types are being investigated for CO2 conversion, so in addition it is essential to be able to model these reactor geometries so that their design can be improved, and the most energy efficient CO2 conversion can be achieved. Modeling the detailed plasma chemistry of CO2 conversion in complex reactors is, however, very time-consuming. This problem can be overcome by using a combination of two different types of model: 0D chemical reaction kinetics models are very suitable for describing the detailed plasma chemistry, while the characteristic features of different reactor geometries can be studied by 2D or 3D fluid models. In the first instance the latter can be developed in argon or helium with a simple chemistry to limit the calculation time; however, the ultimate aim is to implement the more complex CO2 chemistry in these models. In the present paper, examples will be given of both the 0D plasma chemistry models and the 2D and 3D fluid models for the most common plasma reactors used for CO2 conversion in order to emphasize the complementarity of both approaches. Furthermore, based on the modeling insights, the paper discusses the possibilities and limitations of plasma-based CO2 conversion in different types of plasma reactors, as well as what is needed to make further progress in this field.

  20. 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

  1. Progress in the technology of energy conversion from woody biomass in Indonesia

    Institute of Scientific and Technical Information of China (English)

    Tjutju Nurhayati; Yani Waridi; Han Roliadi

    2006-01-01

    Sustainable and renewable natural resources as biomass that contains carbon and hydrogen elements can be a potential raw materials for energy conversion. In Indonesia, they comprise variable-sized wood from forests (i.e. natural forests, plantations and community forests that commonly produce small-diameter logs used as firewood by local people), woody residues from logging and wood industries, oil-palm shell waste from crude palm oil factories, coconut shell wastes from coconut plantations, traditional markets as well as skimmed coconut oil and straws from rice cultivation.Four kinds of energy-conversion technologies have been empirically tested in Indonesia. First, gasification of rubber wood from unproductive rubber trees to generate heat energy for the drying of fermented chocolate seeds. Secondly, energy conversion from organic vegetable waste by implementing thermophylic fermentation methods that produce biogas as a fuel and for generating electricity and also concurrently generate organic by-products called hygen compost. Thirdly, gasification of charcoal and wood sawdust for electricity generation. Finally, environment-friendly energy conversion by carbonizing small-diameter logs, sawdust, wood slabs and coconut shells into charcoal. This yielded charcoal integrated with wood vinegar production through condensation of smoke/vapors emitted during carbonization, thereby mitigating the impact of air pollution. Among the four experimental technologies that of integrated charcoal and wood vinegar production had been spectacularly developed and favored by rural communities. This technology brought added value to the process and product due to the wood vinegar,useful as bio-pesticide,plant-growth hormone and organic fertilizer. Such integrated and environment-friendly production, therefore,should be sustained, because Indonesia occupies a significant and worldwide position as charcoal-producing and marketing country.The technology of integrated wood vinegar

  2. 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.

  3. Mathematical modelling of phenotypic plasticity and conversion to a stem-cell state under hypoxia

    Science.gov (United States)

    Dhawan, Andrew; Madani Tonekaboni, Seyed Ali; Taube, Joseph H.; Hu, Stephen; Sphyris, Nathalie; Mani, Sendurai A.; Kohandel, Mohammad

    2016-02-01

    Hypoxia, or oxygen deficiency, is known to be associated with breast tumour progression, resistance to conventional therapies and poor clinical prognosis. The epithelial-mesenchymal transition (EMT) is a process that confers invasive and migratory capabilities as well as stem cell properties to carcinoma cells thus promoting metastatic progression. In this work, we examined the impact of hypoxia on EMT-associated cancer stem cell (CSC) properties, by culturing transformed human mammary epithelial cells under normoxic and hypoxic conditions, and applying in silico mathematical modelling to simulate the impact of hypoxia on the acquisition of CSC attributes and the transitions between differentiated and stem-like states. Our results indicate that both the heterogeneity and the plasticity of the transformed cell population are enhanced by exposure to hypoxia, resulting in a shift towards a more stem-like population with increased EMT features. Our findings are further reinforced by gene expression analyses demonstrating the upregulation of EMT-related genes, as well as genes associated with therapy resistance, in hypoxic cells compared to normoxic counterparts. In conclusion, we demonstrate that mathematical modelling can be used to simulate the role of hypoxia as a key contributor to the plasticity and heterogeneity of transformed human mammary epithelial cells.

  4. 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.

  5. 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…

  6. Strategies to Increase Representation of Students with Disabilities in Science, Technology, Engineering and Mathematics (STEM)

    Science.gov (United States)

    White, Jeffry L.; Massiha, G. H.

    2015-01-01

    As a nation wrestles with the need to train more professionals, persons with disabilities are undereducated and underrepresented in science, technology, engineering, and mathematics (STEM). The following project was proposed to increase representation of students with disabilities in the STEM disciplines. The program emphasizes an integrated…

  7. Preparing the Future Workforce: Science, Technology, Engineering and Math (STEM) Policy in K-12 Education

    Science.gov (United States)

    Dickman, Anneliese; Schwabe, Amy; Schmidt, Jeff; Henken, Rob

    2009-01-01

    Last December, the Science, Technology, Engineering, and Mathematics (STEM) Education Coalition--a national organization of more than 600 groups representing knowledge workers, educators, scientists, engineers, and technicians--wrote to President-elect Obama urging him to "not lose sight of the critical role that STEM education plays in…

  8. Successful K-12 STEM Education: Identifying Effective Approaches in Science, Technology, Engineering, and Mathematics

    Science.gov (United States)

    National Academies Press, 2011

    2011-01-01

    Science, technology, engineering, and mathematics (STEM) are cultural achievements that reflect our humanity, power our economy, and constitute fundamental aspects of our lives as citizens, consumers, parents, and members of the workforce. Providing all students with access to quality education in the STEM disciplines is important to our nation's…

  9. Facilitating Collaboration across Science, Technology, Engineering & Mathematics (STEM) Fields in Program Development

    Science.gov (United States)

    Ejiwale, James A.

    2014-01-01

    Collaboration plays a major role in interdisciplinary activities among Science, Technology, Engineering & Mathematics (STEM) disciplines or fields. It also affects the relationships among cluster members on the management team. Although effective collaboration does not guarantee success among STEM disciplines, its absence usually assures…

  10. 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.…

  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. 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

    Over many decades assisted reproductive technologies, including artificial insemination, embryo transfer, in vitro production (IVP) of embryos, cloning by somatic cell nuclear transfer (SCNT), and stem cell culture, have been developed with the aim of refining breeding strategies for improved...... of pre-implantation development in cattle, pigs, horses, and dogs. Biological aspects and impact of assisted reproductive technologies including IVP, SCNT, and culture of pluripotent stem cells are also addressed. © 2013 Elsevier Ltd....

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

    OpenAIRE

    Hall, V.; Hinrichs, K.; Lazzari, G.; Betts, D.H.; Hyttel, P.

    2013-01-01

    Over many decades assisted reproductive technologies, including artificial insemination, embryo transfer, in vitro production (IVP) of embryos, cloning by somatic cell nuclear transfer (SCNT), and stem cell culture, have been developed with the aim of refining breeding strategies for improved 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 creat...

  14. 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.

  15. Bioengineering and Stem Cell Technology in the Treatment of Congenital Heart Disease

    Science.gov (United States)

    Bosman, Alexis; Edel, Michael J.; Blue, Gillian; Dilley, Rodney J.; Harvey, Richard P.; Winlaw, David S.

    2015-01-01

    Congenital heart disease places a significant burden on the individual, family and community despite significant advances in our understanding of aetiology and treatment. Early research in ischaemic heart disease has paved the way for stem cell technology and bioengineering, which promises to improve both structural and functional aspects of disease. Stem cell therapy has demonstrated significant improvements in cardiac function in adults with ischaemic heart disease. This finding, together with promising case studies in the paediatric setting, demonstrates the potential for this treatment in congenital heart disease. Furthermore, induced pluripotent stems cell technology, provides a unique opportunity to address aetiological, as well as therapeutic, aspects of disease. PMID:26239354

  16. Systems analysis research for energy conversion and utilization technologies (ECUT). FY 1985 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Eberhardt, J.J.; Gunn, M.E.; Levinson, T.M.

    1985-11-01

    This Annual Report highlights ECUT accomplishments in the Systems Analysis Project for FY 1985. The Systems Analysis Project was established in 1980 along with the ECUT Division. The Systems Analysis mission is to identify, analyze, and assess R and D needs and research program strategies for advanced conservation technologies. The PNL Systems Analysis staff conducts topical research, provides technical studies, and plans program activities in three areas related to energy conversion and utilization technologies: (1) technology assessment, (2) engineering analysis, and (3) project evaluation and review. This report summarizes the technical results and accomplishments of the FY 1985 projects. They relate mostly to tribology, improved ctalysts, regenerative heat exchangers, robotics and electronics industries, and bioprocessing.

  17. Conversion of primordial germ cells to pluripotent stem cells: methods for cell tracking and culture conditions.

    Science.gov (United States)

    Nagamatsu, Go; Suda, Toshio

    2013-01-01

    Primordial germ cells (PGCs) are unipotent cells committed to germ lineage: PGCs can only differentiate into gametes in vivo. However, upon fertilization, germ cells acquire the capacity to differentiate into all cell types in the body, including germ cells. Therefore, germ cells are thought to have the potential for pluripotency. PGCs can convert to pluripotent stem cells in vitro when cultured under specific conditions that include bFGF, LIF, and the membrane-bound form of SCF (mSCF). Here, the culture conditions which efficiently convert PGCs to pluripotent embryonic germ (EG) cells are described, as well as methods used for identifying pluripotent candidate cells during culture.

  18. Preparation for commercial demonstration of biomass-to-ethanol conversion technology. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-01

    The objective of this program was to complete the development of a commercially viable process to produce fuel ethanol from renewable cellulosic biomass. The program focused on pretreatment, enzymatic hydrolysis, and fermentation technologies where Amoco has a unique proprietary position. Assured access to low-cost feedstock is a cornerstone of attractive economics for cellulose to ethanol conversion in the 1990s. Most of Amoco`s efforts in converting cellulosic feedstocks to ethanol before 1994 focused on using paper from municipal solid waste as the feed. However, while many municipalities and MSW haulers expressed interest in Amoco`s technology, none were willing to commit funding to process development. In May, 1994 several large agricultural products companies showed interest in Amoco`s technology, particularly for application to corn fiber. Amoco`s initial work with corn fiber was encouraging. The project work plan was designed to provide sufficient data on corn fiber conversion to convince a major agriculture products company to participate in the construction of a commercial demonstration facility.

  19. Available technology for indirect conversion of coal to methanol and gasoline: a technology and economics assessment. [Technology assessment and comparative evaluation of available processes

    Energy Technology Data Exchange (ETDEWEB)

    Wham, R. M.; Forrester, III, R. C.

    1980-01-01

    The objective of the work was to review and assess the present state of the art of indirect liquid fuels synthesis, with particular emphasis to be placed upon those processes which produce methanol suitable for use as fuel. Following this review, four conceptual designs for indirect conversion of a Western subbituminous coal to methanol and gasoline were prepared. Capital and operating costs for each of the four cases were then estimated. This information was used to calculate the required product selling prices under a base case set of financial ground rules. Results of the methanol production technology assessment and economic assessments of four coal conversion plants are presented.

  20. Therapeutic application of stem cell technology toward the treatment of Parkinson's disease.

    Science.gov (United States)

    Nishimura, Kaneyasu; Takahashi, Jun

    2013-01-01

    Parkinson's disease (PD) is one of the candidate diseases for cell transplantation therapy, since successful clinical experiments have accumulated using human fetal tissue grafting for PD patients. Although some grafted PD patients have shown drastic improvements, several issues still remain with regard to using human fetal tissue. This review highlights the recent advances in stem cell technology toward clinical applications using human pluripotent stem cells. In particular, pluripotent stem cells, such as embryonic stem cells and induced pluripotent stem cells (iPSCs), are the focus as a source of cell transplantation therapy that can be used instead of human fetal tissues. Additionally, efficient methods for stem cell maintenance and differentiation have been developed and improved toward the clinical transition. These advances in the basic technologies have helped accelerate the realization of regenerative medicine. We also review the current topics regarding disease modeling and drug screening using iPSC technology. Finally, we also describe the future prospects of these stem cell research fields toward clinical application.

  1. Small Molecules Greatly Improve Conversion of Human-Induced Pluripotent Stem Cells to the Neuronal Lineage

    Directory of Open Access Journals (Sweden)

    Sally K. Mak

    2012-01-01

    Key success factors for neuronal differentiation are the yield of desired neuronal marker expression, reproducibility, length, and cost. Three main neuronal differentiation approaches are stromal-induced neuronal differentiation, embryoid body (EB differentiation, and direct neuronal differentiation. Here, we describe our neurodifferentiation protocol using small molecules that very efficiently promote neural induction in a 5-stage EB protocol from six induced pluripotent stem cells (iPSC lines from patients with Parkinson’s disease and controls. This protocol generates neural precursors using Dorsomorphin and SB431542 and further maturation into dopaminergic neurons by replacing sonic hedgehog with purmorphamine or smoothened agonist. The advantage of this approach is that all patient-specific iPSC lines tested in this study were successfully and consistently coaxed into the neural lineage.

  2. 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.

  3. Looking to the future following 10 years of induced pluripotent stem cell technologies.

    Science.gov (United States)

    Li, Mo; Izpisua Belmonte, Juan Carlos

    2016-09-01

    The development of induced pluripotent stem cells (iPSCs) has fundamentally changed our view on developmental cell-fate determination and led to a cascade of technological innovations in regenerative medicine. Here we provide an overview of the progress in the field over the past decade, as well as our perspective on future directions and clinical implications of iPSC technology.

  4. Impact of Robotics and Geospatial Technology Interventions on Youth STEM Learning and Attitudes

    Science.gov (United States)

    Nugent, Gwen; Barker, Bradley; Grandgenett, Neal; Adamchuk, Viacheslav I.

    2010-01-01

    This study examined the impact of robotics and geospatial technologies interventions on middle school youth's learning of and attitudes toward science, technology, engineering, and mathematics (STEM). Two interventions were tested. The first was a 40-hour intensive robotics/GPS/GIS summer camp; the second was a 3-hour event modeled on the camp…

  5. Pre-Service Science Teachers' Cognitive Structures Regarding Science, Technology, Engineering, Mathematics (STEM) and Science Education

    Science.gov (United States)

    Hacioglu, Yasemin; Yamak, Havva; Kavak, Nusret

    2016-01-01

    The aim of this study is to reveal pre-service science teachers' cognitive structures regarding Science, Technology, Engineering, Mathematics (STEM) and science education. The study group of the study consisted of 192 pre-service science teachers. A Free Word Association Test (WAT) consisting of science, technology, engineering, mathematics and…

  6. Neutronic Analyses for HEU to LEU fuel conversion of the Massachusetts Institute of Technology.

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, E. H.; Newton, T. H.; Bergeron, A.; Horelik, N.; Stevens, J. G (Nuclear Engineering Division); ( NS)

    2011-03-02

    The Massachusetts Institute of Technology (MIT) reactor (MITR-II), based in Cambridge, Massachusetts, is a research reactor 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 Low Enriched Uranium (LEU) fuel. A new type of LEU fuel based on a mixture of uranium and molybdenum (UMo) is expected to allow the conversion of compact high performance reactors like the MITR-II. This report presents the results of steady state neutronic safety analyses for conversion of MITR-II from the use of HEU fuel to the use of U-Mo LEU fuel. The objective of this work was to demonstrate that the safety analyses meet current requirements for an LEU core replacement of MITR-II.

  7. Advances in stem cells technologies and their commercialization potential.

    Science.gov (United States)

    Kamarul, Tunku

    2013-07-01

    The World Stem Cells & Regenerative Medicine Congress Asia 2013 held in Singapore from 19-21 March 2013 was attended by over 2000 industry attendees and 5000 registered visitors. The focus of the congress was to discuss potential uses of stem cells for various diagnostic and therapeutic applications, their market opportunity and the latest R&D, which would potentially find its way into the market in not too distant future. In addition to the traditional lectures presented by academic and industry experts, there were forums, discussions, posters and exhibits, which provided various platforms for researchers, potential industry partners and even various interest groups to discuss prospective development of the stem cell-related industry.

  8. Nanofluidic Diodes with Dynamic Rectification Properties Stemming from Reversible Electrochemical Conversions in Conducting Polymers.

    Science.gov (United States)

    Pérez-Mitta, Gonzalo; Marmisollé, Waldemar A; Trautmann, Christina; Toimil-Molares, María Eugenia; Azzaroni, Omar

    2015-12-16

    The use of solid state nanochannels as nanofluidic diodes is currently a topic of large interest in nanotechnology. Particularly, there is a focus in the development of nanochannels with surface functionalities that make them responsive to multiple environmental variables. Here, we present for the first time the construction of electrochemical potential- and pH-responsive nanofluidic diodes using a novel approach based on a controlled electrochemical polymerization of aniline on gold-coated polycarbonate asymmetric nanochannels. The polyaniline-modified nanochannels showed three different levels of reversible ionic rectification corresponding to the degrees of oxidation of the conducting polymer. Our results demonstrate that this strategy enables an accurate and reversible control of the rectification properties due to the well-defined and predictable electrochemical conversion of charged species generated on the pore walls. We envision that these results will create novel avenues to fabricate electrochemically modulated nanofluidic diodes using conducting polymers integrated into single conical nanopores.

  9. Electrodeposition of Alloys and Compounds in the Era of Microelectronics and Energy Conversion Technology

    Directory of Open Access Journals (Sweden)

    Giovanni Zangari

    2015-06-01

    Full Text Available Electrochemical deposition methods are increasingly being applied to advanced technology applications, such as microelectronics and, most recently, to energy conversion. Due to the ever growing need for device miniaturization and enhanced performance, vastly improved control of the growth process is required, which in turn necessitates a better understanding of the fundamental phenomena involved. This overview describes the current status of and latest advances in electrodeposition science and technology. Electrochemical growth phenomena are discussed at the macroscopic and atomistic scale, while particular attention is devoted to alloy and compound formation, as well as surface-limited processes. Throughout, the contribution of Professor Foresti and her group to the understanding of electrochemical interfaces and electrodeposition, is highlighted.

  10. 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.

  11. Report of feasibility study on international-cooperation in high efficient energy conversion technology

    Science.gov (United States)

    1993-03-01

    With regard to accelerated introduction of high efficient energy conversion technology to developing countries, the paper investigates the countries' thoughts of the introduction of the technology and the status of the introduction bases. The countries for survey are the Philippines, Indonesia, Malaysia and Thailand. The Philippine government expects to develop cogeneration as well as large power sources and to widen effective use of natural energy. In Indonesia, they largely expect effective use of biomass energy using Stirling engines by international cooperation and the promoted local electrification using standalone distributed fuel cells. In Malaysia, they have great expectations of the introduction of air conditioning facilities using Stirling engines and the use of standalone distributed fuel cells for promotion of local electrification. Thailand hopes for the use of Stirling engines to air conditioning systems, and the development of solar Stirling generators with solar energy as a heat source and electric vehicles.

  12. 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.

  13. VLSI circuit techniques and technologies for ultrahigh speed data conversion interfaces

    Science.gov (United States)

    Wooley, Bruce A.

    1991-04-01

    The performance of digital VLSI signal processing and communications systems is often limited by the data conversion interfaces between digital system-level components and the analog environment in which those components are embedded. The focus of this program has been research into the fundamental nature of such interfaces in systems that digitally process high-bandwidth signals for purposes such as radar imaging, high-resolution graphics, high-definition video, mobile and fiber-optic communications, and broadband instrumentation. Effort has been devoted to the study of both generic circuit functions, such as sampling and comparison, and architectural alternatives relevant to the implementation of high-speed data converters in present and emerging VLSI technologies. Specific results of the research include the design and realization of novel low-power CMOS and BiCMOS sampled-data comparators operating at rates as high as 200 MHz, the exploration of various design approaches to the implementation of high-speed sample-and-hold circuits in CMOS and BiCMOS technologies, and the design of a subranging CMOS analog-to-digital converter that provides 12-bit resolution at a conversion rate of 10 MHz.

  14. Recent Stirling Conversion Technology Developments and Operational Measurements at NASA Glenn Research Center

    Science.gov (United States)

    Oriti, Salvatore M.; Schifer, Nicholas A.

    2010-01-01

    In support of the Advanced Stirling Radioisotope Generator (ASRG) project and other potential applications, NASA Glenn Research Center (GRC) has initiated convertor technology development efforts in the areas of acoustic emission, electromagnetic field mitigation, thermoacoustic Stirling conversion, and multiple-cylinder alpha arrangements of Stirling machines. The acoustic emission measurement effort was developed as a health monitoring metric for several Stirling convertors undergoing life testing. While accelerometers have been used in the past to monitor dynamic signature, the acoustic sensors were chosen to monitor cycle events, such gas bearing operation. Several electromagnetic interference (EMI) experiments were performed on a pair of Advanced Stirling Convertors (ASC). These tests demonstrated that a simple bucking coil was capable of reducing the alternating current (ac) magnetic field below the ASRG system specification. The thermoacoustic Stirling concept eliminates the displacer typically found in Stirling machines by making use of the pressure oscillations of a traveling acoustic wave. A 100 W-class thermoacoustic Stirling prototype manufactured by Northrop Grumman Space and Technology was received and tested. Another thermoacoustic prototype designed and fabricated by Sunpower, Inc., will be tested in the near future. A four cylinder free piston alpha prototype convertor was received from Sunpower, Inc. and has been tested at GRC. This hardware was used as a proof of concept to validate thermodynamic models and demonstrate stable operation of multiple-cylinder free-piston Stirling conversion. This paper will discuss each of these activities and the results they produced.

  15. 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.

  16. 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.

  17. 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.

  18. Conversion of embryonic stem cells into pancreatic beta-cell surrogates guided by ontogeny.

    Science.gov (United States)

    Lees, Justin G; Tuch, Bernard E

    2006-05-01

    Cellular therapies to treat Type 1 diabetes are being devised and the use of human embryonic stem cells (hESCs) offers a solution to the issue of supply, because hESCs can be maintained in a pluripotent state indefinitely. Furthermore, hESCs have advantages in terms of their plasticity and reduced immunogenicity. Several strategies that have so far been investigated indicate that hESCs are capable of differentiating into insulin producing beta-cell surrogates. However the efficiency of the differentiation procedures used is generally quite low and the cell populations derived are often highly heterogenous. A strategy that appears to have long term potential is to design differentiation procedures based on the ontogeny of the beta-cell. The focus of this strategy is to replicate signaling processes that are known to be involved in the maturation of a beta-cell. The earliest pancreatic progenitors found in the developing vertebrate fetus are produced via a process known as gastrulation and form part of the definitive endoderm germ layer. hESCs have recently been differentiated into definitive endoderm with high efficiency using a differentiation procedure that mimics the signaling that occurs during gastrulation and the formation of the definitive endoderm. Subsequent events during pancreas development involve a section of the definitive endoderm forming into pancreatic epithelium, which then branches into the pancreatic mesenchyme to form islet clusters of endocrine cells. A proportion of the endocrine precursor cells within islets develop into insulin producing beta-cells. The challenge currently is to design hESC differentiation procedures that mimic the combined events of these stages of beta-cell development.

  19. Improving K-12 STEM Education Outcomes through Technological Integration

    Science.gov (United States)

    Urban, Michael J., Ed.; Falvo, David A., Ed.

    2016-01-01

    The application of technology in classroom settings has equipped educators with innovative tools and techniques for effective teaching practice. Integrating digital technologies at the elementary and secondary levels helps to enrich the students' learning experience and maximize competency in the areas of science, technology, engineering, and…

  20. Local BMP-SMAD1 Signaling Increases LIF Receptor-Dependent STAT3 Responsiveness and Primed-to-Naive Mouse Pluripotent Stem Cell Conversion Frequency

    Directory of Open Access Journals (Sweden)

    Kento Onishi

    2014-07-01

    Full Text Available Conversion of EpiSCs to naive ESCs is a rare event that is driven by the reestablishment of the naive transcription factor network. In mice, STAT3 activation is sufficient to drive conversion of EpiSCs to the naive pluripotent stem cell (PSC state. However, the lack of responsiveness of EpiSCs to LIF presents a bottleneck in this conversion process. Here, we demonstrate that local accumulation of BMP-SMAD1 signaling, in cooperation with GP130 ligands, enhances the recovery of LIF responsiveness by directly controlling transcription of the LIF receptor (Lif-r. Addition of BMP and LIF to EpiSCs increases both LIF responsiveness and conversion frequencies to naive PSCs. Mechanistically, we show that the transcriptional cofactor P300 plays a critical role by mediating complex formation between STAT3 and SMAD1. This demonstration of how the local microenvironment or stem cell niche reactivates dormant signaling responsiveness and developmental potential may be applicable to other stem cell niche-containing systems.

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

    Science.gov (United States)

    Hall, V; Hinrichs, K; Lazzari, G; Betts, D H; Hyttel, P

    2013-08-01

    Over many decades assisted reproductive technologies, including artificial insemination, embryo transfer, in vitro production (IVP) of embryos, cloning by somatic cell nuclear transfer (SCNT), and stem cell culture, have been developed with the aim of refining breeding strategies for improved 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 of pre-implantation development in cattle, pigs, horses, and dogs. Biological aspects and impact of assisted reproductive technologies including IVP, SCNT, and culture of pluripotent stem cells are also addressed.

  2. 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

    Over many decades assisted reproductive technologies, including artificial insemination, embryo transfer, in vitro production (IVP) of embryos, cloning by somatic cell nuclear transfer (SCNT), and stem cell culture, have been developed with the aim of refining breeding strategies for improved...... 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...... of pre-implantation development in cattle, pigs, horses, and dogs. Biological aspects and impact of assisted reproductive technologies including IVP, SCNT, and culture of pluripotent stem cells are also addressed. © 2013 Elsevier Ltd....

  3. 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…

  4. Supporting Technology at GRC to Mitigate Risk as Stirling Power Conversion Transitions to Flight

    Science.gov (United States)

    Schreiber, Jeffrey G.; Thieme, Lanny G.; Wong, Wayne A.

    2009-01-01

    Stirling power conversion technology has been reaching more advanced levels of maturity during its development for space power applications. The current effort is in support of the Advanced Stirling Radioisotope Generator (ASRG), which is being developed by the U.S. Department of Energy (DOE), Lockheed Martin Space Systems Company (LMSSC), Sunpower Inc., and the NASA Glenn Research Center (GRC). This generator would use two high-efficiency Advanced Stirling Convertors (ASCs) to convert thermal energy from a radioisotope heat source into electricity. Of paramount importance is the reliability of the power system and as a part of this, the Stirling power convertors. GRC has established a supporting technology effort with tasks in the areas of reliability, convertor testing, high-temperature materials, structures, advanced analysis, organics, and permanent magnets. The project utilizes the matrix system at GRC to make use of resident experts in each of the aforementioned fields. Each task is intended to reduce risk and enhance reliability of the convertor as this technology transitions toward flight status. This paper will provide an overview of each task, outline the recent efforts and accomplishments, and show how they mitigate risk and impact the reliability of the ASC s and ultimately, the ASRG.

  5. A Case Study on the Nature of Informal Conversation in an Organization Utilizing Microblogging Technology

    Science.gov (United States)

    Dembeck, Thomas J.

    2013-01-01

    The purpose of this case study was to determine the nature of conversations that occur within an organizational microblog and compare them to traditional informal conversations. Since informal conversations are closely associated with reaction to change, this study explored how organizational microblog conversations may be understood to affect…

  6. A Case Study on the Nature of Informal Conversation in an Organization Utilizing Microblogging Technology

    Science.gov (United States)

    Dembeck, Thomas J.

    2013-01-01

    The purpose of this case study was to determine the nature of conversations that occur within an organizational microblog and compare them to traditional informal conversations. Since informal conversations are closely associated with reaction to change, this study explored how organizational microblog conversations may be understood to affect…

  7. 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)

  8. STEM-Based Computational Modeling for Technology Education

    Science.gov (United States)

    Clark, Aaron C.; Ernst, Jeremy V.

    2008-01-01

    According to professionals in education, change is an ever-present and evolving process. With transformation in education at both state and national levels, technology education must determine a position in this climate of change. This paper reflects the views on the future of technology education based on an ongoing research project. The purpose…

  9. 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.

  10. 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.

  11. McNair Scholars' Science, Technology, Engineering, and Mathematics (STEM) Graduate Experience: A Pilot Study

    Science.gov (United States)

    Bancroft, Senetta F.; Benson, Susan Kushner; Johnson-Whitt, Eugenia

    2016-01-01

    Nationally, racial and gender disparities persist in science, technology, engineering, and mathematics (STEM) disciplines. These disparities are most notable at the doctoral level and are also found in the doctoral outcomes of Ronald E. McNair Postbaccalaureate Achievement Program participants (Scholars) despite opportunities designed to promote…

  12. Diversifying Science, Technology, Engineering, and Mathematics (STEM): An Inquiry into Successful Approaches in Chemistry

    Science.gov (United States)

    Wilson, Zakiya S.; McGuire, Saundra Y.; Limbach, Patrick A.; Doyle, Michael P.; Marzilli, Luigi G.; Warner, Isiah M.

    2014-01-01

    For many years, the U.S. has underutilized its human resources, as evidenced by the pervasive underrepresentation of several racial and ethnic groups within academia in general and the science, technology, engineering, and mathematics (STEM) disciplines, in particular. To address this underutilization, academic departments within U.S. universities…

  13. 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…

  14. Science, Technology, Engineering, and Mathematics (STEM) Curriculum and Seventh Grade Mathematics and Science Achievement

    Science.gov (United States)

    James, Jamie Smith

    2014-01-01

    The purpose of this quantitative research study was to evaluate to what degree Science, Technology, Engineering and Mathematics (STEM) education influenced mathematics and science achievement of seventh grade students in one Middle Tennessee school district. This research used an independent samples t test at the a = 0.05 level to evaluate…

  15. 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.

  16. 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...... barriers or/and eliminate or reduce the risks may result in impairments compromising the opportunities. At the current state of knowledge it is even unclear whether we can develop trustful causal paths between hazards of different natures and their consequences. Hazard identification and risk analysis have...

  17. 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.

  18. 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.

  19. 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.

  20. Conversion of Industrial Buildings and Areas in Terms of Sustainable Development by Using BIM Technology: Analysis and Further Developments

    Directory of Open Access Journals (Sweden)

    Miroslavas Pavlovskis

    2016-02-01

    Full Text Available The article deals with abandoned industrial buildings and lands conversion concept, objectives, problems, beneficial results of a successful conversion for urban expansion, as a complex process of sustainable development. The tools for making effective management and usage of abandoned buildings decisions are considered. The article analyzes the 5D BIM model throughout the life cycle of the building. The foreign good practice is analyzed, where the modern digital technology is used for reconstruction of old buildings. The building information model application possibilities are examined throughout the lifespan of a building. The measures for CO2 emission reduction in the construction sector are proposed. Finaly, the model for conversion of abanoded buildings is proposed, based on MCDM and BIM technologies.

  1. Ethical and social issues of embryonic stem cell technology.

    Science.gov (United States)

    Cregan, K

    2005-02-01

    Therapeutic cloning is debated as a cure for a host of diseases in the developed world. The likely source for the materials for therapeutic cloning, human ova, would be poor women and women from the developing world. The ethics and potential social consequences inherent in this technology are fraught and encourage the com modification and abstraction of one of the fundamental conditions of human life.

  2. New and advanced energy conversion technologies. Analysis of cogeneration, combined and integrated cycles

    Energy Technology Data Exchange (ETDEWEB)

    Korobitsyn, M.A.

    1998-04-03

    Advances within power cycles, integration of cycles, and combination of existing technologies are the possible ways to improve performance of small- and medium-scale power technology. Identification and development of new energy conversion technologies and systems for distributed power generation applications are the objectives of the New Energy Conversion Technologies (NECT) programme of the Netherlands Agency for Energy and Environment (Novem). The part of the programme, which is dedicated to the development of new and improved combinations of existing energy conversion technologies, defines the structure of this thesis. At the beginning, the basic thermodynamic cycles and their specific features are described. Because no single cycle can offer high efficiency due to the intrinsic limitations and the impossibility to operate within a broad temperature range, combined and advanced cycles are addressed. Combined cycles do not suffer from the drawbacks of the single cycles, since the heat rejected by the topping cycle is utilized by the bottoming one, and better performance can be obtained. The basic cycles are combined according to their temperature level: high-temperature cycles are good candidates for the topping application, and medium- or low-temperature cycles for bottoming. Of the combined cycles considered, each cycle is outlined and its schematic diagram is given. In addition to the combined cycles, improvements within a particular cycle are discussed. The scope of the NECT programme covers power and heat production, so industrial cogeneration is assessed in various configurations (steam boiler, gas turbine, heat pumps) and operating modes. Subsequently, several technologies, which are selected for further development within the NECT programme, are analyzed in detail. One of the configurations is the Joule/Joule combined cycle, which consists of an existing gas turbine and an air bottoming turbine. The bottoming cycle adds 20-30% to the power output, which

  3. 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.

  4. Ke Alahaka Program of the Advanced Technology Solar Telescope (ATST) Mitigation Initiative Provides STEM Workshops for Native Hawaiian Students

    Science.gov (United States)

    Coopersmith, A.; Cie, D. K.; Naho`olewa, D.; Chirico, J.

    2012-12-01

    The Advanced Technology Solar Telescope (ATST) Mitigation Initiative and the Kahikina O Ka Lā Program are NSF-funded projects at the University of Hawai`i Maui College. These projects will provide instruction and activities intended to increase diversity in STEM or STEM-related careers. Ke Alahaka, the 2012 summer bridge program, was offered to Native Hawaiian high-school students who indicated an interest in STEM areas. Three STEM-content workshops were offered including Marine Science, Sustainable Energy Technology, and Computer Science and Engineering. Students attended hands-on classes three days a week for a month concentrating on only one of the three topics. On the other days, students participated in a Hawaiian Studies course designed to provide a cultural context for the STEM instruction. Focus groups and other program assessments indicate that 50% of the 60 students attending the workshops intend to pursue a STEM major during their undergraduate studies.

  5. 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.

  6. Technology Outlook for STEM+ Education 2013-2018: An NMC Horizon Project Sector Analysis

    Science.gov (United States)

    Johnson, L.; Adams Becker, S.; Estrada, V.; Martín, S.

    2013-01-01

    The "Technology Outlook for STEM+ Education 2013-2018: An NMC Horizon Project Sector Analysis" reflects a collaborative research effort between the New Media Consortium (NMC), the Centro Superior para la Enseñanza Virtual (CSEV), the Departamento de Ingeniería Eléctrica, Electrónica y de Control at the Universidad Nacional de Educación a…

  7. Integrative Technologies and Knowledge Gatekeepers: Bridging the Gap between Epistemic Communities in the Case of Stem Cell Science

    Science.gov (United States)

    Wink, Rudiger

    2008-01-01

    The article analyses the role of gatekeepers between regional and disciplinary innovation systems in stem cell research as a case of integrative technologies. Which kind of gatekeepers is needed and which function can be fulfilled, differs along the knowledge value chain. Empirical results are used to explain the rationality of stem cell policies…

  8. 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…

  9. Integrative Technologies and Knowledge Gatekeepers: Bridging the Gap between Epistemic Communities in the Case of Stem Cell Science

    Science.gov (United States)

    Wink, Rudiger

    2008-01-01

    The article analyses the role of gatekeepers between regional and disciplinary innovation systems in stem cell research as a case of integrative technologies. Which kind of gatekeepers is needed and which function can be fulfilled, differs along the knowledge value chain. Empirical results are used to explain the rationality of stem cell policies…

  10. Science and Technology Educators' Enacted Curriculum: Areas of Possible Collaboration for an Integrative STEM Approach in Public Schools

    Science.gov (United States)

    Brown, Josh; Brown, Ryan; Merrill, Chris

    2012-01-01

    Science, Technology, Engineering, and Mathematics (STEM) teachers teach multiple concepts that lend themselves to possible collaboration on a daily basis. Much like Metz's (2009) insightful discussion about the importance of science educators creating partnerships in the community "outside the school walls," integrative STEM teaching also requires…

  11. The Development and Validation of a Measure of Student Attitudes toward Science, Technology, Engineering, and Math (S-STEM)

    Science.gov (United States)

    Unfried, Alana; Faber, Malinda; Stanhope, Daniel S.; Wiebe, Eric

    2015-01-01

    Using an iterative design along with multiple methodological approaches and a large representative sample, this study presents reliability, validity, and fairness evidence for two surveys measuring student attitudes toward science, technology, engineering, and math (S-STEM) and interest in STEM careers for (a) 4th- through 5th-grade students…

  12. 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

  13. 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

  14. 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.)

  15. 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…

  16. I. Evaluation of the impact of alternative light technology on male broiler chicken growth, feed conversion, and allometric characteristics.

    Science.gov (United States)

    Rogers, Allison G; Pritchett, Elizabeth M; Alphin, Robert L; Brannick, Erin M; Benson, Eric R

    2015-03-01

    This study evaluates the impact of light-emitting diode (LED), cold cathode fluorescent (CCFL), and incandescent lamps on broiler performance. Male Ross 708 broilers (n=672) were raised to 6 wk age in 8 black-out modified large colony houses, under identical intermittent lighting conditions using 4 unique types of lamps, which were gradually dimmed throughout the study. Incandescent lamps served as the control; experimental technologies tested included CCFL and 2 different LED lamps. Each technology was tested in duplicate for each of 4 trials (8 replications total per technology) conducted across the course of one year to account for seasonal variance. Live performance for each technology was evaluated using live broiler body weight (BW), weight gain, feed conversion, and mortality. Birds were removed from each house at 7, 14, 35, and 42 d to be humanely euthanized, weighed, and necropsied for allometric tissue sample analysis. Relative to the technologies tested, results indicate that birds raised under incandescent lamps had significantly higher BW by 42 d, compared to birds raised under CCFL lamps, which had poorer BW performance (P=0.03). Birds raised under both LED technologies grew to final BWs similar to those raised under incandescent light, with significant differences in neither feed conversion nor mortality.

  17. Concise Review: Stem Cell Microenvironment on a Chip: Current Technologies for Tissue Engineering and Stem Cell Biology.

    Science.gov (United States)

    Park, DoYeun; Lim, Jaeho; Park, Joong Yull; Lee, Sang-Hoon

    2015-11-01

    Stem cells have huge potential in many therapeutic areas. With conventional cell culture methods, however, it is difficult to achieve in vivo-like microenvironments in which a number of well-controlled stimuli are provided for growing highly sensitive stem cells. In contrast, microtechnology-based platforms offer advantages of high precision, controllability, scalability, and reproducibility, enabling imitation of the complex physiological context of in vivo. This capability may fill the gap between the present knowledge about stem cells and that required for clinical stem cell-based therapies. We reviewed the various types of microplatforms on which stem cell microenvironments are mimicked. We have assigned the various microplatforms to four categories based on their practical uses to assist stem cell biologists in using them for research. In particular, many examples are given of microplatforms used for the production of embryoid bodies and aggregates of stem cells in vitro. We also categorized microplatforms based on the types of factors controlling the behaviors of stem cells. Finally, we outline possible future directions for microplatform-based stem cell research, such as research leading to the production of well-defined environments for stem cells to be used in scaled-up systems or organs-on-a-chip, the regulation of induced pluripotent stem cells, and the study of the genetic states of stem cells on microplatforms. Stem cells are highly sensitive to a variety of physicochemical cues, and their fate can be easily altered by a slight change of environment; therefore, systematic analysis and discrimination of the extracellular signals and intracellular pathways controlling the fate of cells and experimental realization of sensitive and controllable niche environments are critical. This review introduces diverse microplatforms to provide in vitro stem cell niches. Microplatforms could control microenvironments around cells and have recently attracted much

  18. Concise Review: Stem Cell Microenvironment on a Chip: Current Technologies for Tissue Engineering and Stem Cell Biology

    Science.gov (United States)

    Park, DoYeun; Lim, Jaeho; Park, Joong Yull

    2015-01-01

    Stem cells have huge potential in many therapeutic areas. With conventional cell culture methods, however, it is difficult to achieve in vivo-like microenvironments in which a number of well-controlled stimuli are provided for growing highly sensitive stem cells. In contrast, microtechnology-based platforms offer advantages of high precision, controllability, scalability, and reproducibility, enabling imitation of the complex physiological context of in vivo. This capability may fill the gap between the present knowledge about stem cells and that required for clinical stem cell-based therapies. We reviewed the various types of microplatforms on which stem cell microenvironments are mimicked. We have assigned the various microplatforms to four categories based on their practical uses to assist stem cell biologists in using them for research. In particular, many examples are given of microplatforms used for the production of embryoid bodies and aggregates of stem cells in vitro. We also categorized microplatforms based on the types of factors controlling the behaviors of stem cells. Finally, we outline possible future directions for microplatform-based stem cell research, such as research leading to the production of well-defined environments for stem cells to be used in scaled-up systems or organs-on-a-chip, the regulation of induced pluripotent stem cells, and the study of the genetic states of stem cells on microplatforms. Significance Stem cells are highly sensitive to a variety of physicochemical cues, and their fate can be easily altered by a slight change of environment; therefore, systematic analysis and discrimination of the extracellular signals and intracellular pathways controlling the fate of cells and experimental realization of sensitive and controllable niche environments are critical. This review introduces diverse microplatforms to provide in vitro stem cell niches. Microplatforms could control microenvironments around cells and have recently

  19. 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.

  20. 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

  1. An Investigation of the Linkage between Technology-Based Activities and STEM Major Selection in 4-Year Postsecondary Institutions in the United States: Multilevel Structural Equation Modelling

    Science.gov (United States)

    Lee, Ahlam

    2015-01-01

    Among the disciplines of science, technology, engineering, and math (STEM), much attention has been paid to the influences of math- and science-related learning contexts on students' STEM major selection. However, the technology and engineering learning contexts that are linked to STEM major selection have been overlooked. In response, a…

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

    CERN Document Server

    Schmuck, Claudine

    2016-01-01

    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.

  3. 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

  4. 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.

  5. 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.

  6. Efficient Conversion of Spermatogonial Stem Cells to Phenotypic and Functional Dopaminergic Neurons via the PI3K/Akt and P21/Smurf2/Nolz1 Pathway.

    Science.gov (United States)

    Yang, Hao; Liu, Yang; Hai, Yanan; Guo, Ying; Yang, Shi; Li, Zheng; Gao, Wei-Qiang; He, Zuping

    2015-12-01

    Parkinson's disease (PD) is a common neurodegenerative syndrome characterized by loss of midbrain dopaminergic (DA) neurons. Generation of functional dopaminergic (DA) neurons is of unusual significance for treating Parkinson's disease (PD). However, direct conversion of spermatogonial stem cells (SSCs) to functional DA neurons without being reprogrammed to a pluripotent status has not been achieved. Here, we report an efficient approach to obtain morphological, phenotypic, and functional DA neurons from SSCs using a specific combination of olfactory ensheathing cell-conditioned medium (OECCM) and several defined growth factors (DGF). By following the current protocol, direct conversion of SSCs (both SSC line and primary SSCs) to neural cells and DA neurons was demonstrated by expression of numerous phenotypic genes and proteins for neural cells, as well as cell morphological features. More significantly, SSCs-derived DA neurons acquired neuronal functional properties such as synapse formation, electrophysiology activity, and dopamine secretion. Furthermore, PI3K/Akt pathway and p21/Nolz1 cascades were activated whereas Smurf2 was inactivated, leading to cell cycle exit during the conversion of SSCs into DA neurons. Collectively, this study could provide sufficient neural cells from SSCs for applications in the treatment of PD and offers novel insights into mechanisms underlying neural system development from the line of germ cells.

  7. Precision Analysis of Trimble Rtx Surveying Technology with Xfill Function in the Context of Obtained Conversion Observations

    Directory of Open Access Journals (Sweden)

    Krzyżek Robert

    2015-02-01

    Full Text Available As a result of traditional geodetic surveying we usually achieve observations which are then used for calculating rectangular coordinates onto a plane along with precision evaluation. In this article the surveying methods are presented in which the situation is different. Test measurements were carried out, consisting in the measurement of a fragment of detailed control network in RTK (Real Time Kinematic and RTX (Real Time Extended mode with xFill function. First, the rectangular coordinates onto a plane (through the transformation of data ellipsoidal were obtained, on the basis of which the conversion observations were determined and they were compared with each other, as well as with reference parameters - conversion observations out of detailed control network adjustment with use of the method of least squares. The results of the study allow to verify the precision and application possibilities of conversion observations obtained thanks to Trimble RTX technology with xFill function. Application of this surveying method in typical geodetic tasks is fully justifiable. Nevertheless, it is recommendable to be aware of the correlations of absolute or relative values obtained in RTX procedure to reference parameters, which in turn will enable conclusive verification of the possibilities of Trimble RTX technology application in certain geodetic surveys.

  8. Federal Science, Technology, Engineering, and Mathematics (STEM) Education: 5-Year Strategic Plan. A Report from the Committee on STEM Education National Science and Technology Council

    Science.gov (United States)

    Executive Office of the President, 2013

    2013-01-01

    Given that many jobs of the future will be STEM jobs, that our K-12 system is "middle of the pack" in international comparisons, and that progress on STEM education at multiple levels is critical to building a just and inclusive society, there is an urgent need to continue to improve STEM education in the United States. Much knowledge…

  9. Using Pivotal Response Training and Technology to Engage Preschoolers with Autism in Conversations

    Science.gov (United States)

    Stockall, Nancy; Dennis, Lindsay R.

    2014-01-01

    It is well known that children with autism spectrum disorder (ASD) demonstrate a significant delay in language development that impacts their ability to engage in robust conversations. In this article the authors discuss two specific elements of pivotal response training--motivation and self-initiations--for children with ASD. Specific…

  10. Assuring the U.S. Department of Defense a Strong Science, Technology, Engineering, and Mathematics (STEM) Workforce

    Science.gov (United States)

    National Academies Press, 2012

    2012-01-01

    The ability of the nation's military to prevail during future conflicts, and to fulfill its humanitarian and other missions, depends on continued advances in the nation's technology base. A workforce with robust Science, Technology, Engineering and Mathematics (STEM) capabilities is critical to sustaining U.S. preeminence. Today, however, the STEM…

  11. 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…

  12. 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

  13. Instructional Technology Innovation in the Liberal Arts Classroom: A Conversation with the Maryville College Faculty Instructional Technology (FIT) Fellows.

    Science.gov (United States)

    Roberts, Gina; Berry, Chad; Nugent, Chris; Wentz, Karen; Cowan, Peggy; O'Gorman, Mark

    Maryville College's (Tennessee) first Faculty Instructional Technology (FIT) Fellows, who received funding and release time to develop technology-based instructional materials for their courses, are developing and implementing exciting projects in history, religion, freshman seminar, and political sciences courses. In this paper, the FIT Fellows…

  14. PDGF-AB and 5-Azacytidine induce conversion of somatic cells into tissue-regenerative multipotent stem cells

    Science.gov (United States)

    Chandrakanthan, Vashe; Yeola, Avani; Kwan, Jair C.; Oliver, Rema A.; Qiao, Qiao; Kang, Young Chan; Zarzour, Peter; Beck, Dominik; Boelen, Lies; Unnikrishnan, Ashwin; Villanueva, Jeanette E.; Nunez, Andrea C.; Knezevic, Kathy; Palu, Cintia; Nasrallah, Rabab; Carnell, Michael; Macmillan, Alex; Whan, Renee; Yu, Yan; Hardy, Philip; Grey, Shane T.; Gladbach, Amadeus; Delerue, Fabien; Ittner, Lars; Mobbs, Ralph; Walkley, Carl R.; Purton, Louise E.; Ward, Robyn L.; Wong, Jason W. H.; Hesson, Luke B.; Walsh, William; Pimanda, John E.

    2016-01-01

    Current approaches in tissue engineering are geared toward generating tissue-specific stem cells. Given the complexity and heterogeneity of tissues, this approach has its limitations. An alternate approach is to induce terminally differentiated cells to dedifferentiate into multipotent proliferative cells with the capacity to regenerate all components of a damaged tissue, a phenomenon used by salamanders to regenerate limbs. 5-Azacytidine (AZA) is a nucleoside analog that is used to treat preleukemic and leukemic blood disorders. AZA is also known to induce cell plasticity. We hypothesized that AZA-induced cell plasticity occurs via a transient multipotent cell state and that concomitant exposure to a receptive growth factor might result in the expansion of a plastic and proliferative population of cells. To this end, we treated lineage-committed cells with AZA and screened a number of different growth factors with known activity in mesenchyme-derived tissues. Here, we report that transient treatment with AZA in combination with platelet-derived growth factor–AB converts primary somatic cells into tissue-regenerative multipotent stem (iMS) cells. iMS cells possess a distinct transcriptome, are immunosuppressive, and demonstrate long-term self-renewal, serial clonogenicity, and multigerm layer differentiation potential. Importantly, unlike mesenchymal stem cells, iMS cells contribute directly to in vivo tissue regeneration in a context-dependent manner and, unlike embryonic or pluripotent stem cells, do not form teratomas. Taken together, this vector-free method of generating iMS cells from primary terminally differentiated cells has significant scope for application in tissue regeneration. PMID:27044077

  15. 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

    2017-02-17

    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.

  16. Folded down-conversion mixer for a 60 GHz receiver architecture in 65-nm CMOS technology

    Institute of Scientific and Technical Information of China (English)

    Najam Muhammad AMIN; Zhi-gong WANG‡; Zhi-qun LI

    2014-01-01

    We present the design of a folded down-conversion mixer which is incorporated at the final down-conversion stage of a 60 GHz receiver. The mixer employs an ac-coupled current reuse transconductance stage. It performs well under low supply voltages, and is less sensitive to temperature variations and process spread. The mixer operates at an input radio frequency (RF) band ranging from 10.25 to 13.75 GHz, with a fixed local oscillator (LO) frequency of 12 GHz, which down-converts the RF band to an intermediate frequency (IF) band ranging from dc to 1.75 GHz. The mixer is designed in a 65 nm low power (LP) CMOS process with an active chip area of only 0.0179 mm2. At a nominal supply voltage of 1.2 V and an IF of 10 MHz, a maximum voltage conversion gain (VCG) of 9.8 dB, a double sideband noise figure (DSB-NF) of 11.6 dB, and a linearity in terms of input 1 dB compression point (Pin,1dB) of−13 dBm are measured. The mixer draws a current of 5 mA from a 1.2 V supply dissipating a power of only 6 mW.

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

    Science.gov (United States)

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

    2017-03-01

    Not Available Project supported by the National Natural Science Foundation of China (Grant Nos. 21103194, 51506205, and 21673243), the Science and Technology Planning Project of Guangdong Province, China (Grant Nos. 2014A010106018 and 2013A011401011), the Guangdong-Hong Kong Joint Innovation Project of Guangdong Province, China (Grant No. 2014B050505015), the Special Support Program of Guangdong Province, China (Grant No. 2014TQ01N610), the Director Innovation Foundation of Guangzhou Institute of Energy Conversion, China (Grant No. y307p81001), and the Solar Photothermal Advanced Materials Engineering Research Center Construction Project of Guangdong Province, China (Grant No. 2014B090904071).

  18. Active High Power Conversion Efficiency Rectifier With Built-In Dual-Mode Back Telemetry in Standard CMOS Technology.

    Science.gov (United States)

    Bawa, G; Ghovanloo, M

    2008-09-01

    In this paper, we present an active rectifier with high power conversion efficiency (PCE) implemented in a 0.5- mum 5 V standard CMOS technology with two modes of built-in back telemetry; short- and open-circuit. As a rectifier, it ensures a PCE > 80%, taking advantage of active synchronous rectification technique in the frequency range of 0.125-1 MHz. The built-in complementary back telemetry feature can be utilized in implantable microelectronic devices (IMD), wireless sensors, and radio frequency identification (RFID) applications to reduce the silicon area, increase the data rate, and improve the reading range and robustness in load shift keying (LSK).

  19. The AECT HistoryMakers Project: Conversations with Leaders in Educational Technology

    Science.gov (United States)

    Lockee, Barbara B.; Song, Kibong; Li, Wei

    2014-01-01

    The early beginnings and evolution of the field of educational technology (ET) have been documented by various scholars in the field. Recently, another form of historical documentation has been undertaken through a project of the Association for Educational Communications and Technology (AECT). The AECT HistoryMakers Project is a collaborative…

  20. Conversion to stem-cell state in response to microenvironmental cues is regulated by balance between epithelial and mesenchymal features in lung cancer cells.

    Science.gov (United States)

    Andriani, Francesca; Bertolini, Giulia; Facchinetti, Federica; Baldoli, Erika; Moro, Massimo; Casalini, Patrizia; Caserini, Roberto; Milione, Massimo; Leone, Giorgia; Pelosi, Giuseppe; Pastorino, Ugo; Sozzi, Gabriella; Roz, Luca

    2016-02-01

    Cancer cells within a tumor are functionally heterogeneous and specific subpopulations, defined as cancer initiating cells (CICs), are endowed with higher tumor forming potential. The CIC state, however, is not hierarchically stable and conversion of non-CICs to CICs under microenvironment signals might represent a determinant of tumor aggressiveness. How plasticity is regulated at the cellular level is however poorly understood. To identify determinants of plasticity in lung cancer we exposed eight different cell lines to TGFβ1 to induce EMT and stimulate modulation of CD133(+) CICs. We show that response to TGFβ1 treatment is heterogeneous with some cells readily switching to stem cell state (1.5-2 fold CICs increase) and others being unresponsive to stimulation. This response is unrelated to original CICs content or extent of EMT engagement but is tightly dependent on balance between epithelial and mesenchymal features as measured by the ratio of expression of CDH1 (E-cadherin) to SNAI2. Epigenetic modulation of this balance can restore sensitivity of unresponsive models to microenvironmental stimuli, including those elicited by cancer-associated fibroblasts both in vitro and in vivo. In particular, tumors with increased prevalence of cells with features of partial EMT (hybrid epithelial/mesenchymal phenotype) are endowed with the highest plasticity and specific patterns of expression of SNAI2 and CDH1 markers identify a subset of tumors with worse prognosis. In conclusion, here we describe a connection between a hybrid epithelial/mesenchymal phenotype and conversion to stem-cell state in response to external stimuli. These findings have implications for current endeavors to identify tumors with increased plasticity.

  1. 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

  2. Uncovering Underlying Assumptions Regarding Education and Technology in Educational Reform Efforts A conversation with Dr. Larry Johnson

    Directory of Open Access Journals (Sweden)

    Gabriela Melano

    2000-11-01

    Full Text Available Educational systems around the world, and specifically in the United States, have long been awaiting for genuine reform efforts. Technology is often perceived as a panacea, if not as a crucial instrument in any educational reform effort. In a conversation with one of his students, Doctor Johnson discusses how the underlying assumptions embedded in our current schooling practices need to be seriously reviewed before any technology strategy is considered. New understandings, as opposed to mere information, is what schools need to reach in order to transform themselves. Finally, Dr. Johnson provides two brief examples, one in the United States and another in México, were hermeneutical approaches have been used for educational reform endeavors.

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. Microencapsulation technology: a powerful tool for integrating expansion and cryopreservation of human embryonic stem cells.

    Science.gov (United States)

    Serra, Margarida; Correia, Cláudia; 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.

  8. Microencapsulation technology: a powerful tool for integrating expansion and cryopreservation of human embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Margarida Serra

    Full Text Available 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.

  9. 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

  10. China Pushes Ahead with Technology for "Conversion of Coal into Oil"

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Chinese's Academy of Sciences has recently announced an R&D project of a pilot plant scale process on the basis of the Fischer-Tropsch synthesis technology developed in the Institute of Coal Chemistry (ICC),according to the recent reports from the Chinese news media.Currently, major breakthroughs have been made in the low cost catalyst production, the efficient reactor design, and the process integration, Sun Yuhan, director of ICC, said recently. He added that recent technology developed in ICC has greatly reduced the cost ofsynthesis part in the whole process, indicating the economic and environmental feasibility for the development of commercial complexes in China, and a pilot plant test is under way in coalenriched Shanxi province.

  11. FCJ-172 Posthumanism, Technogenesis, and Digital Technologies: A Conversation with N. Katherine Hayles

    Directory of Open Access Journals (Sweden)

    Holger Pötzsch

    2014-12-01

    Full Text Available An interview with N. Katherine Hayles by Holger Pötzsch. Hayles discusses the arc of her work, from her book How We Became Posthuman to her current exploration of nonconscious cognition. She also discusses technogenesis, the digital humanities and digital technologies more generally, and more recent engagements with objects and the sciences, including the work of object oriented ontology and Karen Barad.

  12. 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...college. Three students have gone through the NRL internships and now are full time employees at NRL. This pattern of direct corporate, government and

  13. 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.

  14. Development of Hydrothermal Liquefaction and Upgrading Technologies for Lipid-Extracted Algae Conversion to Liquid Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Yunhua; Albrecht, Karl O.; Elliott, Douglas C.; Hallen, Richard T.; Jones, Susanne B.

    2013-10-01

    Bench-scale tests were performed for lipid-extracted microalgae (LEA) conversion to liquid fuels via hydrotreating liquefaction (HTL) and upgrading processes. Process simulation and economic analysis for a large-scale LEA HTL and upgrading system were developed based on the best available test results. The system assumes an LEA feed rate of 608 dry metric ton/day and that the feedstock is converted to a crude HTL bio-oil and further upgraded via hydrotreating and hydrocracking to produce liquid hydrocarbon fuels, mainly alkanes. Performance and cost results demonstrate that HTL would be an effective option to convert LEA to liquid fuel. The liquid fuels annual yield was estimated to be 26.9 million gallon gasoline-equivalent and the overall energy efficiency at higher heating value basis was estimated to be 69.5%. The minimum fuel selling price (MFSP) was estimated to be $0.75/L with LEA feedstock price at $33.1 metric ton at dry basis and 10% internal rate of return. A sensitivity analysis indicated that the largest effects to production cost would come from the final products yields and the upgrading equipments cost. The impact of plant scale on MFSP was also investigated.

  15. Rapid and efficient conversion of integration-free human induced pluripotent stem cells to GMP-grade culture conditions.

    Directory of Open Access Journals (Sweden)

    Jens Durruthy-Durruthy

    Full Text Available Data suggest that clinical applications of human induced pluripotent stem cells (hiPSCs will be realized. Nonetheless, clinical applications will require hiPSCs that are free of exogenous DNA and that can be manufactured through Good Manufacturing Practice (GMP. Optimally, derivation of hiPSCs should be rapid and efficient in order to minimize manipulations, reduce potential for accumulation of mutations and minimize financial costs. Previous studies reported the use of modified synthetic mRNAs to reprogram fibroblasts to a pluripotent state. Here, we provide an optimized, fully chemically defined and feeder-free protocol for the derivation of hiPSCs using synthetic mRNAs. The protocol results in derivation of fully reprogrammed hiPSC lines from adult dermal fibroblasts in less than two weeks. The hiPSC lines were successfully tested for their identity, purity, stability and safety at a GMP facility and cryopreserved. To our knowledge, as a proof of principle, these are the first integration-free iPSCs lines that were reproducibly generated through synthetic mRNA reprogramming that could be putatively used for clinical purposes.

  16. 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.

  17. 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

    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...... gas as an alternative energy source reduces global warming, non-renewable energy use and eutrophication but increases acidification and respiratory inorganics. The relative performance of straw gasification versus direct combustion and fossil fuel references does not change with varying assumptions...

  18. 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.

  19. Development and characterization of functional composite materials for advanced energy conversion technologies

    OpenAIRE

    Fan, Liangdong

    2013-01-01

    The solid oxide fuel cell (SOFC) is a potential high efficient electrochemical device for vehicles, auxiliary power units and large-scale stationary power plants combined heat and power application. The main challenges of this technology for market acceptance are associated with cost and lifetime due to the high temperature (700-1000 oC) operation and complex cell structure, i.e. the conventional membrane electrode assemblies. Therefore, it has become a top R&D goal to develop SOFCs for l...

  20. Advanced imaging approaches for regenerative medicine: Emerging technologies for monitoring stem cell fate in vitro and in vivo.

    Science.gov (United States)

    Kupfer, Molly E; Ogle, Brenda M

    2015-10-01

    The future of regenerative medicine relies on our ability to control stem cell fate in order to produce functional tissues. Stem cells are the preferred cell source for tissue engineering endeavors and regenerative medicine therapies due to their high potency and capacity for expansion. However, their potency also makes them very difficult to control, as they are in a constant state of flux. Therefore, in order to advance research in regenerative medicine, it is necessary to be able to monitor cell state and phenotype both in vitro and in vivo. This review will detail the imaging technologies currently in use to monitor stem cell phenotype, migration, and differentiation. In addition to providing examples of the most recent work in this area, we will also discuss the future of imaging technologies for regenerative medicine, and how current imaging modalities might be utilized to image specific cell functionality in order to track stem cell fate. The research area of imaging stem cells is progressing toward identifying mature and differentiating cells not only by phenotypic markers, but also by visualizing cell function. Many of the cutting-edge modalities detailed in this review have the potential to be harnessed toward this goal.

  1. On the challenge of developing advanced technologies for electrochemical energy storage and conversion

    Directory of Open Access Journals (Sweden)

    Hyun Deog Yoo

    2014-04-01

    Full Text Available The accelerated production of sophisticated miniaturized mobile electronic devices, challenges such as the electrochemical propulsion of electric vehicles (EVs, and the need for large-scale storage of sustainable energy (i.e. load-levelling applications motivate and stimulate the development of novel rechargeable batteries and super-capacitors. While batteries deliver high energy density but limited cycle life and power density, super-capacitors provide high power density and very prolonged cycling. Lithium-ion batteries are the focus of intensive R&D efforts because they promise very high energy density that may be suitable for electrical propulsion. Here, we review research on batteries with an emphasis on Li-ion battery technology, examining its suitability for EV applications. We also briefly examine other battery systems that may be of importance for load-levelling applications, including rechargeable magnesium batteries. We give a short review of the status of technologies beyond Li-ion batteries, including Li–sulfur and Li–oxygen systems. Finally, we briefly discuss recent progress in the R&D of advanced super-capacitors.

  2. Materials technology for coal-conversion processes. Seventeenth quarterly report, January-March 1979

    Energy Technology Data Exchange (ETDEWEB)

    Ellingson, W. A.

    1979-01-01

    Studies of slag attack on refractories were continued, utilizing conditions relevant to MHD applications. Addition of 10 wt % K/sub 2/O seed to the slag did not increase its corrosive effect on the refractories tested. A hot gas-stream cleanup erosion-monitoring system using an ANL-developed nondestructive ultrasonic system was installed at the Morgantown Energy Technology Center (METC) during this period and was 75% completed. Characteristic-slope values obtained from broadband and resonant-band acoustic-emission transducers during rapid heating of a 95% Al/sub 2/O/sub 3/ refractory panel are consistent with theory. Corrosion information on type and thickness of corrosion-product layers was obtained on Incoloy 800, 310 stainless steel, Inconel 671 and 871 and 982/sup 0/C. Fluid-bed corrosion studies involving sulfation accelerators have shown that addition of 0.3 mol % CaCl/sub 2/ has no significant effect on corrosion behavior of the alloys studied. However, 0.5 mol % NaCl or 1.9 mol % Na/sub 2/CO/sub 3/ increases the corrosion rates of most materials. Failure analyses were performed on components from the slagging gasifier and liquefaction unit at the Grand Forks Energy Technology Center, and a ball valve from the METC Valve Dynamic Test Unit.

  3. 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.

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

    Science.gov (United States)

    2014-05-01

    believe; that gender and socioeconomic gaps related to STEM develop in the preschool years; and that teaching STEM at these early ages does not require...2  3.  Current U.S. STEM Status 5  3.1  Current STEM Education Curriculum in Preschools ......................................................7  3.2...could result in no funding support, such as with No Child Left Behind. Recent statistics released by Condoleezza Rice and Joel I. Klein, chairs of the

  5. 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

  6. 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

  7. 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.

  8. 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.

  9. 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)

  10. 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.

  11. ECUT: Energy Conversion and Utilization Technologies program. Heterogeneous catalysis modeling program concept

    Science.gov (United States)

    Voecks, G. E.

    1983-01-01

    Insufficient theoretical definition of heterogeneous catalysts is the major difficulty confronting industrial suppliers who seek catalyst systems which are more active, selective, and stable than those currently available. In contrast, progress was made in tailoring homogeneous catalysts to specific reactions because more is known about the reaction intermediates promoted and/or stabilized by these catalysts during the course of reaction. However, modeling heterogeneous catalysts on a microscopic scale requires compiling and verifying complex information on reaction intermediates and pathways. This can be achieved by adapting homogeneous catalyzed reaction intermediate species, applying theoretical quantum chemistry and computer technology, and developing a better understanding of heterogeneous catalyst system environments. Research in microscopic reaction modeling is now at a stage where computer modeling, supported by physical experimental verification, could provide information about the dynamics of the reactions that will lead to designing supported catalysts with improved selectivity and stability.

  12. 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

  13. 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)

  14. Direct cell fate conversion of human somatic stem cells into cone and rod photoreceptor-like cells by inhibition of microRNA-203

    OpenAIRE

    Choi, Soon Won; Shin, Ji-Hee; Kim, Jae-Jun; Shin, Tae-Hoon; Seo, Yoojin; Kim, Hyung-Sik; Kang, Kyung-Sun

    2016-01-01

    Stem cell-based photoreceptor differentiation strategies have been the recent focus of therapies for retinal degenerative diseases. Previous studies utilized embryonic stem (ES) cells and neural retina differentiation cocktails, including DKK1 and Noggin. Here, we show a novel microRNA-mediated strategy of retina differentiation from somatic stem cells, which are potential allogeneic cell sources. Human amniotic epithelial stem cells (AESCs) and umbilical cord blood-derived mesenchymal stem c...

  15. 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.

  16. 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.

  17. Modelling and treating amyotrophic lateral sclerosis through induced-pluripotent stem cells technology.

    Science.gov (United States)

    Bohl, Delphine; Pochet, Roland; Mitrecic, Dinko; Nicaise, Charles

    2016-01-01

    Amyotrophic lateral sclerosis (ALS) is an adult-onset neurodegenerative disease affecting primarily the population of motor neurons, even though a non-cell autonomous component, involving neighbouring non-neuronal cells, is more and more described. Despite 140 years of disease experience, still no efficient treatment exists against ALS. The inability to readily obtain the faulty cell types relevant to ALS has impeded progress in drug discovery for decades. However, the pioneer work of Shinya Yamanaka in 2007 in the stem cell field was a real breakthrough. Recent advances in cell reprogramming now grant access to significant quantities of CNS disease-affected cells. Induced pluripotent stem cells (iPSc) have been recently derived from patients carrying mutations linked to familial forms of ALS as well as from sporadic patients. Precise and mature protocols allow now their differentiation into ALS-relevant cell subtypes; sustainable and renewable sources of human motor neurons or glia are being available for ALS disease modelling, drug screening or for the development of cell therapies. In few years, the proof-of-concept was made that ALS disease-related phenotypes can be reproduced with iPSc and despite some remaining challenges, we are now not so far to provide platforms for the investigation of ALS therapeutics. This paper also reviews the pioneering studies regarding the applicability of iPSc technology in ALS animal models. From modest slowing down of ALS progression to no severe adverse effects, iPSc-based cell therapy resulted in promising premises in ALS preclinical paradigms, although long-term surveys are highly recommended.

  18. 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.

  19. Materials technology for coal-conversion processes. Progress report, January-March 1980

    Energy Technology Data Exchange (ETDEWEB)

    Ellingson, William A.

    1980-06-01

    The program entails nondestructive testing, failure analysis, and studies of erosive wear, corrosion, and refractory degradation. Analysis of recent refractory-slag interaction tests suggests that as the chromia content is increased from 10 to 32%, the primary reaction product changes from calcium hexaluminate to spinel, significantly increasing the corrosion resistance of the refractory. Field reliability of the high-temperature ultrasonic erosion scanner was demonstrated at both a coal liquefaction plant (SRC at Tacoma, WA) and a coal gasification plant (Morgantown, WV). Continuous high-temperature operation has been demonstrated and an accuracy of +-0.025 mm seems achievable. Equipment has been ordered for field tests of passive acoustic systems at Exxon. This includes a four-channel tape recorder, differential amplifiers, and signal conditioners. Corrosion studies have been completed on effects of multicomponent gas environments on corrosion mechanisms and uniaxial tensile properties of Fe-Ni-Cr alloys. Results of these and other tests utilizing 10,000-h exposures suggest that corrosion rates of 0.6 mm/y can be expected. Failure analysis activities included studies of compressor diaphragms from the Grand Forks Energy Technology Center coal-liquefaction continuous-process unit. Cracks were found in two of the three diaphragms. Failure of an internal solids transfer line from HYGAS appears to have been caused by severe localized sulfidation of the high-nickel Inconel 182 weld metal used to fabricate the line.

  20. 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

  1. 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

  2. The potential application of a Cobalt Chrome Molybdenum femoral stem with functionally graded orthotropic structures manufactured using Laser Melting technologies.

    Science.gov (United States)

    Hazlehurst, K B; Wang, C J; Stanford, M

    2013-12-01

    The cementless fixation of porous coated femoral stems is a common technique employed for Total Hip Arthroplasty (THA). With the rate of revision surgery appearing to rise and younger more active patients requiring primary surgery it can be thought that alternative methods for increasing implant longevity need to be considered. The stress shielding of periprosthetic bone still remains a contributing factor to implant loosening, caused through a mismatch in stiffness between the implant and the bone. However, the ability to achieve stiffness matching characteristics is being realised through the use of Additive Layer Manufacturing (ALM) technologies and Functionally Graded Materials (FGM). This paper proposes an alternative design methodology for a monoblock Cobalt Chrome Molybdenum (CoCrMo) femoral stem. It hypothesises that a femoral stem suitable for cementless fixation can be manufactured using Laser Melting (LM) technology offering orthotropic functionally graded porous structures with similar mechanical properties to human bone. The structure and mechanical properties of the natural femur have been used as a basis for the design criteria which hypothesises that through a combination of numerical analysis and physical testing, an optimal design can be proposed to provide a lightweight, customised femoral stem that can reduce the risk of implant loosening through stress shielding whilst maintaining bone-implant interface stability.

  3. Development of 3D in vitro platform technology to engineer mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Hosseinkhani H

    2012-06-01

    Full Text Available Hossein Hosseinkhani,1 Po-Da Hong,1 Dah-Shyong Yu,2 Yi-Ru Chen,3 Diana Ickowicz,4 Ira-Yudovin Farber,4 Abraham J Domb41Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology (TAIWANTECH, 2Nanomedicine Research Center, National Defense Medical Center, Taipei, Taiwan, 3Department of Biomedical Engineering, National Yang-Ming University, Taipei, Taiwan, 4Institute of Drug Research, The Center for Nanoscience and Nanotechnology, School of Pharmacy-Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, IsraelAbstract: This study aims to develop a three-dimensional in vitro culture system to genetically engineer mesenchymal stem cells (MSC to express bone morphogenic protein-2. We employed nanofabrication technologies borrowed from the spinning industry, such as electrospinning, to mass-produce identical building blocks in a variety of shapes and sizes to fabricate electrospun nanofiber sheets comprised of composites of poly (glycolic acid and collagen. Homogenous nanoparticles of cationic biodegradable natural polymer were formed by simple mixing of an aqueous solution of plasmid DNA encoded bone morphogenic protein-2 with the same volume of cationic polysaccharide, dextran-spermine. Rat bone marrow MSC were cultured on electrospun nanofiber sheets comprised of composites of poly (glycolic acid and collagen prior to the incorporation of the nanoparticles into the nanofiber sheets. Bone morphogenic protein-2 was significantly detected in MSC cultured on nanofiber sheets incorporated with nanoparticles after 2 days compared with MSC cultured on nanofiber sheets incorporated with naked plasmid DNA. We conclude that the incorporation of nanoparticles into nanofiber sheets is a very promising strategy to genetically engineer MSC and can be used for further applications in regenerative medicine therapy.Keywords: 3D culture, nanoparticles, nanofibers, polycations, tissue engineering

  4. Human Inducible Pluripotent Stem Cells and Autism Spectrum Disorder: Emerging Technologies.

    Science.gov (United States)

    Nestor, Michael W; Phillips, Andre W; Artimovich, Elena; Nestor, Jonathan E; Hussman, John P; Blatt, Gene J

    2016-05-01

    Autism Spectrum Disorder (ASD) is a behaviorally defined neurodevelopmental condition. Symptoms of ASD cover the spectrum from mild qualitative differences in social interaction to severe communication and social and behavioral challenges that require lifelong support. Attempts at understanding the pathophysiology of ASD have been hampered by a multifactorial etiology that stretches the limits of current behavioral and cell based models. Recent progress has implicated numerous autism-risk genes but efforts to gain a better understanding of the underlying biological mechanisms have seen slow progress. This is in part due to lack of appropriate models for complete molecular and pharmacological studies. The advent of induced pluripotent stem cells (iPSC) has reinvigorated efforts to establish more complete model systems that more reliably identify molecular pathways and predict effective drug targets and candidates in ASD. iPSCs are particularly appealing because they can be derived from human patients and controls for research purposes and provide a technology for the development of a personalized treatment regimen for ASD patients. The pluripotency of iPSCs allow them to be reprogrammed into a number of CNS cell types and phenotypically screened across many patients. This quality is already being exploited in protocols to generate 2-dimensional (2-D) and three-dimensional (3-D) models of neurons and developing brain structures. iPSC models make powerful platforms that can be interrogated using electrophysiology, gene expression studies, and other cell-based quantitative assays. iPSC technology has limitations but when combined with other model systems has great potential for helping define the underlying pathophysiology of ASD. Autism Res 2016, 9: 513-535. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

  5. Development of 3D in vitro platform technology to engineer mesenchymal stem cells.

    Science.gov (United States)

    Hosseinkhani, Hossein; Hong, Po-Da; Yu, Dah-Shyong; Chen, Yi-Ru; Ickowicz, Diana; Farber, Ira-Yudovin; Domb, Abraham J

    2012-01-01

    This study aims to develop a three-dimensional in vitro culture system to genetically engineer mesenchymal stem cells (MSC) to express bone morphogenic protein-2. We employed nanofabrication technologies borrowed from the spinning industry, such as electrospinning, to mass-produce identical building blocks in a variety of shapes and sizes to fabricate electrospun nanofiber sheets comprised of composites of poly (glycolic acid) and collagen. Homogenous nanoparticles of cationic biodegradable natural polymer were formed by simple mixing of an aqueous solution of plasmid DNA encoded bone morphogenic protein-2 with the same volume of cationic polysaccharide, dextran-spermine. Rat bone marrow MSC were cultured on electrospun nanofiber sheets comprised of composites of poly (glycolic acid) and collagen prior to the incorporation of the nanoparticles into the nanofiber sheets. Bone morphogenic protein-2 was significantly detected in MSC cultured on nanofiber sheets incorporated with nanoparticles after 2 days compared with MSC cultured on nanofiber sheets incorporated with naked plasmid DNA. We conclude that the incorporation of nanoparticles into nanofiber sheets is a very promising strategy to genetically engineer MSC and can be used for further applications in regenerative medicine therapy.

  6. Prospects of static energy conversion technology for nuclear power application%核能利用中的静态能量转换技术

    Institute of Scientific and Technical Information of China (English)

    王心亮; 段宗武; 陈虹

    2011-01-01

    Static energy conversion is a technology without moving mechanical parts to convert heat into electricity. The static energy conversion technology is paid much attention in nucleat power application field for its little maintenance, low vibration, eximious sealability and so on. Today thermoelectric and thermionic converters has been used,but the efficiencies of energy conversion are too low. In order to make the efficiencies competitive with dynamic system many new technologies are studied, involved thermophtovoltaic, alkali metal thermoelectric conversion, thermoacoustic power conversion and magnetohydrodynamics conversion. In this paper the principles and status of these future thchnologies are introduced, and the feasibility for application of each technology is evaluated.%静态能量转换是没有旋转部件的能量转换技术,因其所具有的运行维护少、振动噪声低、系统密封性能好等优点而在核能应用领域一直受到关注.已应用的是热电偶和热离子技术,但转换效率太低.目前出现了多种高效率的静态能量转换技术,包括热光伏、碱金属热电转换、热声转换和磁流体发电等,本文对这些未来的静态能量转换技术的原理和研究状况进行了介绍,并对未来实用化的可能进行了评估.

  7. 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.

  8. 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

  9. Department of Defense Science, Technology, Engineering, and Mathematics (STEM) Education Workshop on Computing Education

    Science.gov (United States)

    2010-10-18

    School Cybercampus ChicTech Tech Ambassadors Competition Arduino Project Lead the Way Pico Crickets™ Workshops MIT Media Lab , STEM Rays, UMASS...Computer Science Equity Alliance Way Arduino “Kids Ahead” SMU Caruth August 2010 14 , STEM Rays, UMASS US FIRST Robotics Competition Autonomous

  10. 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…

  11. 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 an Arlon 25N substrate to shield the sensitive noise measurement. Conversion loss measurements of both mixers is performed both for on-wafer and packaged versions. The experimental results shows that the Schottky diode mixer exhibits a 1/f noise corner frequency of 250 kHz, while the diode connected HBT...

  12. 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

  13. 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.

  14. Non-viral approaches for direct conversion into mesenchymal cell types: Potential application in tissue engineering.

    Science.gov (United States)

    Lee, Eun-Seo; Kim, Seung Hyun L; Lee, Hwajin; Hwang, Nathaniel S

    2016-05-01

    Acquiring adequate number of cells is one of the crucial factors to apply tissue engineering strategies in order to recover critical-sized defects. While the reprogramming technology used for inducing pluripotent stem cells (iPSCs) opened up a direct path for generating pluripotent stem cells, a direct conversion strategy may provide another possibility to obtain desired cells for tissue engineering. In order to convert a somatic cell into any other cell type, diverse approaches have been investigated. Conspicuously, in contrast to traditional viral transduction method, non-viral delivery of conversion factors has the merit of lowering immune responses and provides safer genetic manipulation, thus revolutionizing the generation of directly converted cells and its application in therapeutics. In addition, applying various microenvironmental modulations have potential to ameliorate the conversion of somatic cells into different lineages. In this review, we discuss the recent progress in direct conversion technologies, specifically focusing on generating mesenchymal cell types. © 2016 Wiley Periodicals, Inc.

  15. 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.

  16. Conversion of a CHO cell culture process from perfusion to fed-batch technology without altering product quality.

    Science.gov (United States)

    Meuwly, F; Weber, U; Ziegler, T; Gervais, A; Mastrangeli, R; Crisci, C; Rossi, M; Bernard, A; von Stockar, U; Kadouri, A

    2006-05-03

    During the development of a new drug product, it is a common strategy to develop a first-generation process with the aim to rapidly produce material for pre-clinical and early stage clinical trials. At a later stage of the development, a second-generation process is then introduced with the aim to supply late-stage clinical trials as well as market needs. This work was aimed at comparing the performance of two different CHO cell culture processes (perfusion and fed-batch) used for the production of a therapeutically active recombinant glycoprotein at industrial pilot-scale. The first-generation process was based on the Fibra-Cel packed-bed perfusion technology. It appeared during the development of the candidate drug that high therapeutic doses were required (>100mg per dose), and that future market demand would exceed 100 kg per year. This exceeded by far the production capacity of the first-generation process, and triggered a change of technology from a packed-bed perfusion process with limited scale-up capabilities to a fed-batch process with scale-up potential to typical bioreactor sizes of 15m(3) or more. The productivity per bioreactor unit volume (in product m(-3)year(-1)) of the fed-batch process was about 70% of the level reached with the first-generation perfusion process. However, since the packed-bed perfusion system was limited in scale (0.6m(3) maximum) compared to the volumes reached in suspension cultures (15m(3)), the fed-batch was selected as second-generation process. In fact, the overall process performance (in product year(-1)) was about 18-fold higher for the fed-batch compared to the perfusion mode. Data from perfusion and fed-batch harvests samples indicated that comparable product quality (relative abundance of monomers dimers and aggregates; N-glycan sialylation level; isoforms distribution) was obtained in both processes. To further confirm this observation, purification to homogeneity of the harvest material from both processes, followed

  17. Science, Technology, Engineering, and Mathematics (STEM) career attractiveness system dynamics modeling

    Energy Technology Data Exchange (ETDEWEB)

    Kelic, Andjelka [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Zagonel, Aldo A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2008-12-01

    A system dynamics model was developed in response to the apparent decline in STEM candidates in the United States and a pending shortage. The model explores the attractiveness of STEM and STEM careers focusing on employers and the workforce. Policies such as boosting STEM literacy, lifting the H-1B visa cap, limiting the offshoring of jobs, and maintaining training are explored as possible solutions. The system is complex, with many feedbacks and long time delays, so solutions that focus on a single point of the system are not effective and cannot solve the problem. A deeper understanding of parts of the system that have not been explored to date is necessary to find a workable solution.

  18. Science, Technology, Engineering, and Mathematics (STEM) career attractiveness system dynamics modeling.

    Energy Technology Data Exchange (ETDEWEB)

    Kelic, Andjelka; Zagonel, Aldo A.

    2008-12-01

    A system dynamics model was developed in response to the apparent decline in STEM candidates in the United States and a pending shortage. The model explores the attractiveness of STEM and STEM careers focusing on employers and the workforce. Policies such as boosting STEM literacy, lifting the H-1B visa cap, limiting the offshoring of jobs, and maintaining training are explored as possible solutions. The system is complex, with many feedbacks and long time delays, so solutions that focus on a single point of the system are not effective and cannot solve the problem. A deeper understanding of parts of the system that have not been explored to date is necessary to find a workable solution.

  19. 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.

  20. 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.

  1. Exploiting bacterial peptide display technology to engineer biomaterials for neural stem cell culture.

    Science.gov (United States)

    Little, Lauren E; Dane, Karen Y; Daugherty, Patrick S; Healy, Kevin E; Schaffer, David V

    2011-02-01

    Stem cells are often cultured on substrates that present extracellular matrix (ECM) proteins; however, the heterogeneous and poorly defined nature of ECM proteins presents challenges both for basic biological investigation of cell-matrix investigations and translational applications of stem cells. Therefore, fully synthetic, defined materials conjugated with bioactive ligands, such as adhesive peptides, are preferable for stem cell biology and engineering. However, identifying novel ligands that engage cellular receptors can be challenging, and we have thus developed a high throughput approach to identify new adhesive ligands. We selected an unbiased bacterial peptide display library for the ability to bind adult neural stem cells (NSCs), and 44 bacterial clones expressing peptides were identified and found to bind to NSCs with high avidity. Of these clones, four contained RGD motifs commonly found in integrin binding domains, and three exhibited homology to ECM proteins. Three peptide clones were chosen for further analysis, and their synthetic analogs were adsorbed on tissue culture polystyrene (TCPS) or grafted onto an interpenetrating polymer network (IPN) for cell culture. These three peptides were found to support neural stem cell self-renewal in defined medium as well as multi-lineage differentiation. Therefore, bacterial peptide display offers unique advantages to isolate bioactive peptides from large, unbiased libraries for applications in biomaterials engineering.

  2. Stem cell technology for tendon regeneration: current status, challenges, and future research directions

    Directory of Open Access Journals (Sweden)

    Lui PP

    2015-12-01

    Full Text Available Pauline Po Yee Lui Headquarter, Hospital Authority, Hong Kong SAR, People's Republic of China Abstract: Tendon injuries are a common cause of physical disability. They present a clinical challenge to orthopedic surgeons because injured tendons respond poorly to current treatments without tissue regeneration and the time required for rehabilitation is long. New treatment options are required. Stem cell-based therapies offer great potential to promote tendon regeneration due to their high proliferative, synthetic, and immunomodulatory activities as well as their potential to differentiate to the target cell types and undergo genetic modification. In this review, I first recapped the challenges of tendon repair by reviewing the anatomy of tendon. Next, I discussed the advantages and limitations of using different types of stem cells compared to terminally differentiated cells for tendon tissue engineering. The safety and efficacy of application of stem cells and their modified counterparts for tendon tissue engineering were then summarized after a systematic literature search in PubMed. The challenges and future research directions to enhance, optimize, and standardize stem cell-based therapies for augmenting tendon repair were then discussed. Keywords: stem cells, tendon repair, tendon tissue engineering, tendon injuries

  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. 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…

  5. The Use of Virtual and Simulated Teaching and Learning Environments: Inviting Gifted Students into Science, Technology, Engineering, and Mathematics Careers (STEM) through Summer Partnerships

    Science.gov (United States)

    Dieker, Lisa; Grillo, Kelly; Ramlakhan, Nirmala

    2012-01-01

    New technologies and virtual environments are emerging globally, yet the way these tools can impact the learning and future career paths of students who are gifted is limited in the literature at this time. The purpose of this article is to provide a summary of how a science, technology, engineering, and mathematics (STEM) summer camp, based on…

  6. Direct cell fate conversion of human somatic stem cells into cone and rod photoreceptor-like cells by inhibition of microRNA-203.

    Science.gov (United States)

    Choi, Soon Won; Shin, Ji-Hee; Kim, Jae-Jun; Shin, Tae-Hoon; Seo, Yoojin; Kim, Hyung-Sik; Kang, Kyung-Sun

    2016-07-05

    Stem cell-based photoreceptor differentiation strategies have been the recent focus of therapies for retinal degenerative diseases. Previous studies utilized embryonic stem (ES) cells and neural retina differentiation cocktails, including DKK1 and Noggin. Here, we show a novel microRNA-mediated strategy of retina differentiation from somatic stem cells, which are potential allogeneic cell sources. Human amniotic epithelial stem cells (AESCs) and umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) treated with a retina differentiation cocktail induced gene expressions of retina development-relevant genes. Furthermore, microRNA-203 (miR-203) is abundantly expressed in human AESCs and human UCB-MSCs. This miR-203 is predicted to target multiple retina development-relevant genes, particularly DKK1, CRX, RORβ, NEUROD1, NRL and THRB. The inhibition of miR-203 induced a retina differentiation of AESCs and UCB-MSCs. Moreover, successive treatments of anti-miR-203 led to the expression of both mature photoreceptor (PR) markers, rhodopsin and opsin. In addition, we determined that CRX, NRL and DKK1 are direct targets of miR-203 using a luciferase assay. Thus, the work presented here suggests that somatic stem cells can potentially differentiate into neural retina cell types when treated with anti-miR-203. They may prove to be a source of both PR subtypes for future allogeneic stem cell-based therapies of non-regenerative retina diseases.

  7. Undergraduate Experiences of Division I Athlete Science, Technology, Engineering, and Mathematics (STEM) Graduates

    Science.gov (United States)

    Comeaux, Eddie; Bachman, Tina; Burton, Rena M.; Aliyeva, Aida

    2016-08-01

    Employing the conceptual model developed by Comeaux and Harrison (Coll Stud Aff J 30(1):75-87, 2011), this study explored the undergraduate experience of Division I athlete STEM graduates. Data collection involved 17 in-depth interviews with former athletes at two research-intensive, public institutions. Results revealed that pre-college characteristics, involvement in purposeful STEM-related activities, and sport participation, as well as academic support and guidance within athletic departments, play important roles in shaping the experiences of athletes who earn STEM degrees. Implications for student affairs professionals, faculty, and others who frequently interact with college athletes and are committed to creating more equitable educational environments are discussed.

  8. Undergraduate Experiences of Division I Athlete Science, Technology, Engineering, and Mathematics (STEM) Graduates

    Science.gov (United States)

    Comeaux, Eddie; Bachman, Tina; Burton, Rena M.; Aliyeva, Aida

    2017-02-01

    Employing the conceptual model developed by Comeaux and Harrison (Coll Stud Aff J 30(1):75-87, 2011), this study explored the undergraduate experience of Division I athlete STEM graduates. Data collection involved 17 in-depth interviews with former athletes at two research-intensive, public institutions. Results revealed that pre-college characteristics, involvement in purposeful STEM-related activities, and sport participation, as well as academic support and guidance within athletic departments, play important roles in shaping the experiences of athletes who earn STEM degrees. Implications for student affairs professionals, faculty, and others who frequently interact with college athletes and are committed to creating more equitable educational environments are discussed.

  9. Safety and efficient ex vivo expansion of stem cells using platelet-rich plasma technology.

    Science.gov (United States)

    Anitua, Eduardo; Prado, Roberto; Orive, Gorka

    2013-09-01

    The goal of this Review is to provide an overview of the cell culture media supplements used in the ex vivo expansion of stem cells intended for cell therapy. Currently, the gold standard is the culture supplemented with fetal bovine serum, however, their use in cell therapy raises many concerns. The alternatives to its use are presented, ranging from the use of human serum to platelet-rich plasma (PRP), to serum-free media or extracellular matrix components. Finally, various growth factors present in PRP are described, which make it a safe and effective stem cell expansion supplement. These growth factors could be responsible for their efficiency, as they increase both stem cell proliferation and survival. The different PRP formulations are also discussed, as well as the need for protocol standardization.

  10. Emerging technologies and developing countries: stem cell research regulation and Argentina.

    Science.gov (United States)

    Harmon, Shawn H E

    2008-08-01

    Given its intimate relationship with the human body and its environment, biotechnology innovation, and more particularly stem cell research innovations as a part thereof, implicate diverse social and moral/ethical issues. This paper explores some of the most important and controversial moral concerns raised by human embryonic stem cell research (and the closely associated field of cloning), focusing on concerns relating to the wellbeing of the embryo and the wellbeing of society (the collective). It then considers how and whether these concerns are dealt with in regulatory instruments in Argentina, a southern developing country, examining in particular whether the values underlying these concerns have been translated into practical and effective rules reflective of the primary moral positions advanced. It concludes that Argentina's current state of stem cell research governance fails to consistently reflect the moral positions that have formed and is inadequate given Argentina's activity in this field.

  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. Using database technology to improve STEM student retention: A total quality management approach to early alert and intervention

    Directory of Open Access Journals (Sweden)

    Sam Khoury

    2012-04-01

    Full Text Available Students at risk of dropping out of Science, Technology, Engineering, and Mathematics (STEM programs often display signs that indicate they are at risk. A need exists to identify at risk STEM students early and to develop and implement effective intervention strategies that utilize the Total Quality Management (TQM approach. Most of all, a database system is needed to track this early intervention process, if retention rates are to be improved. To address this need at a small community college in North Carolina, a system was developed and underwent a pilot study in Fall 2009 and Spring 2010. The two pilot groups were compared to the two control groups to identify differences in retention, course credit completion rates, and grade point averages (GPA. The first pilot group displayed no significant differences, while the second pilot group displayed significant differences in most of the areas analyzed in the study, indicating a database system can be used to improve STEM student retention. While the second of the two pilot groups displayed promising results, managerial and logistical issues, such as less than optimal instructor involvement, impeded success were identified. This paper will describe the design, implementation, and the preliminary results of this study and outlines the need for further research that confirms these preliminary findings.

  13. [Pluripotent stem cells: maintenance of genetic and epigenetic stability and prospects of cell technologies].

    Science.gov (United States)

    Gordeeva, O F; Mitalipov, Sh M

    2008-01-01

    Permanent lines of pluripotent stem cells can be obtained from humans and monkeys using different techniques and from different sources--inner cell mass of the blastocyst, primary germ cells, parthenogenetic oocytes, and mature spermatogonia--as well as by transgenic modification of various adult somatic cells. Despite different origin, all pluripotent lines demonstrate considerable similarity of the major biological properties: active self-renewal and differentiation into various somatic and germ cells in vitro and in vivo, similar gene expression profiles, and similar cell cycle structure. Ten years of intense studies on the stability of different human and monkey embryonic stem cells demonstrated that, irrespective of their origin, long-term in vitro cultures lead to the accumulation of chromosomal and gene mutations as well as epigenetic changes that can cause oncogenic transformation of cells. This review summarizes the research data on the genetic and epigenetic stability of different lines of pluripotent stem cells after long-term in vitro culture. These data were used to analyze possible factors of the genome and epigenome instability in pluripotent lines. The prospects of using pluripotent stem cells of different origin in cell therapy and pharmacological studies were considered.

  14. Undergraduate Experiences of Division I Athlete Science, Technology, Engineering, and Mathematics (STEM) Graduates

    Science.gov (United States)

    Comeaux, Eddie; Bachman, Tina; Burton, Rena M.; Aliyeva, Aida

    2017-01-01

    Employing the conceptual model developed by Comeaux and Harrison ("Coll Stud Aff J" 30(1):75-87, 2011), this study explored the undergraduate experience of Division I athlete STEM graduates. Data collection involved 17 in-depth interviews with former athletes at two research-intensive, public institutions. Results revealed that…

  15. 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

  16. 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.

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

    Science.gov (United States)

    Schneider, Annette; Spitkovsky, Dimitry; Riess, Peter; Molcanyi, Marek; Kamisetti, Naidu; Maegele, Marc; Hescheler, Jürgen; Schaefer, Ute

    2008-01-01

    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. 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…

  19. Conversational Dominance.

    Science.gov (United States)

    Esau, Helmut; Poth, Annette

    Details of conversational behavior can often not be interpreted until the social interaction, including the rights and obligations of the participants, their intent, the topic, etc., has been defined. This paper presents a model of conversation in which the conversational image a person presents in a given conversational situation is a function of…

  20. Stem cell technology for tendon regeneration: current status, challenges, and future research directions

    OpenAIRE

    2015-01-01

    Pauline Po Yee Lui Headquarter, Hospital Authority, Hong Kong SAR, People's Republic of China Abstract: Tendon injuries are a common cause of physical disability. They present a clinical challenge to orthopedic surgeons because injured tendons respond poorly to current treatments without tissue regeneration and the time required for rehabilitation is long. New treatment options are required. Stem cell-based therapies offer great potential to promote tendon regeneration due to their h...

  1. Induced pluripotent stem cell (iPS) technology: promises and challenges

    Institute of Scientific and Technical Information of China (English)

    MIGUELA Esteban; GAN Yi; QIN DaJiang; PEI DuanQing

    2009-01-01

    In 2006,an article published in Cell by Shinya Yamanaka took by surprise the stem cell research community.By performing systematic retroviral transduction of factors enriched in embryonic stem (ES) cells,the authors demonstrated the reprogramming of mouse fibroblasts into an ES cell-like state.These cells,baptized iPS (induced pluripotent stem) cells,were immediately recognized as a ground-breaking discovery.Subsequently,the same authors and other groups reported a similar achievement with human fibroblasts.Two years later,the number of top quality papers on iPS is astonishing,and interest in the scientific community has risen to a fever pitch.But although iPS has the potential to revolutionize Regenerative Medicine,important questions still remain unanswered.Work from multiple laboratories worldwide including ours is focused on deciphering the molecular mechanisms of iPS,and trying to improve the technique to make it suitable for the clinic.In this review article we briefly discuss the past,present and future of iPS,with emphasis on urgent issues to be solved.

  2. Stem cell technology for bone regeneration: current status and potential applications

    Directory of Open Access Journals (Sweden)

    Asatrian G

    2015-02-01

    Full Text Available Greg Asatrian,1 Dalton Pham,1,2 Winters R Hardy,3 Aaron W James,1–3 Bruno Peault3,4 1Dental and Craniofacial Research Institute and Section of Orthodontics, School of Dentistry, 2Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, 3UCLA/Orthopaedic Hospital Department of Orthopaedic Surgery and the Orthopaedic Hospital Research Center, Los Angeles, CA, USA; 4Medical Research Council Centre for Regenerative Medicine, Edinburgh, Scotland, UK Abstract: Continued improvements in the understanding and application of mesenchymal stem cells (MSC have revolutionized tissue engineering. This is particularly true within the field of skeletal regenerative medicine. However, much remains unknown regarding the native origins of MSC, the relative advantages of different MSC populations for bone regeneration, and even the biologic safety of such unpurified, grossly characterized cells. This review will first summarize the initial discovery of MSC, as well as the current and future applications of MSC in bone tissue engineering. Next, the relative advantages and disadvantages of MSC isolated from distinct tissue origins are debated, including the MSC from adipose, bone marrow, and dental pulp, among others. The perivascular origin of MSC is next discussed. Finally, we briefly comment on pluripotent stem cell populations and their possible application in bone tissue engineering. While continually expanding, the field of MSC-based bone tissue engineering and regeneration shows potential to become a clinical reality in the not-so-distant future.Keywords: mesenchymal stem cell, pericyte, bone tissue engineering, MSC, ASC, DMSC

  3. Intensified technology for microalgal CO2 fixation and conversion from flue gas%微藻固定转化烟气CO2强化技术

    Institute of Scientific and Technical Information of China (English)

    姜加伟; 程丽华; 徐新华; 张林; 陈欢林

    2014-01-01

    全球气候变暖和能源危机是21世纪影响人类生存发展的重要问题。微藻由于具有利用太阳能、固定CO2并转化为油脂等产物的能力以及环境适应性强、光合效率高、繁殖快等优势,微藻固碳技术有望成为缓解温室效应和能源危机的有效方法之一,但是该技术目前仍存在去除烟气 CO2转化油脂效率低的问题。本文分析了微藻固碳过程中碳传递转化途径,介绍了强化微藻固定与转化烟气 CO2的技术研究,包括微藻固碳与转化油脂的生物强化、微藻固定 CO2的反应器强化、微藻固定与转化 CO2技术的耦合,重点讨论了强化微藻固碳与转化的生物技术和膜技术研究现状及存在问题。最后指出微藻固碳的生物技术、膜技术及其他多技术的耦合有望进一步提升烟气CO2的高效固定与转化,是强化微藻固定转化烟气CO2的重要研究方向。%Microalgae has the strong ability to convert CO2 into cellular lipid product , better environmental adaptability , higher photosynthetic efficiency and the higher reproduction rate. Therefore,carbon dioxide fixation by microalgae has become one of the effective solutions to greenhouse effect and energy crisis. The bottle neck of this technology lies in the low efficiency of CO2 fixation and conversion into cellular lipid product. This paper introduced the process of CO2 fixation and conversion into organic carbon components of microalgae cell. The progresses on intensified fixation and conversion of CO2 from flue gas,including the stimulated CO2 fixation and conversion into lipid,the intensified CO2 fixation by membrane technology in a photobioreactor and the coupling of various technologies. The application of biotechnology and the membrane technology in microalgae field were elaborated and discussed. This paper also discussed the integration of microalgae biotechnology,membrane technology and the coupling of other technologies

  4. 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…

  5. 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.

  6. Evaluation of a novel non-destructive catch and release technology for harvesting autologous adult stem cells.

    Directory of Open Access Journals (Sweden)

    Nicholas Bryan

    Full Text Available BACKGROUND: Cell based therapies are required now to meet the critical care needs of paediatrics and healthy ageing in an increasingly long-lived human population. Repair of compromised tissue by supporting autologous regeneration is a life changing objective uniting the fields of medical science and engineering. Adipose stem cells (adSCs are a compelling candidate for use in cell based medicine due to their plasticity and residence in numerous tissues. Adipose found in all animals contains a relatively high concentration of stem cells and is easily isolated by a minimally invasive clinical intervention; such as liposuction. METHODS: This study utilised primary rat adipose to validate a novel strategy for selecting adult stem cells. Experiments explored the use of large, very dense cell-specific antibody loaded isolation beads (diameter 5x-10x greater than target cells which overcome the problem of endocytosis and have proved to be very effective in cell isolation from minimally processed primary tissue. The technique also benefited from pH mediated release, which enabled elution of captured cells using a simple pH shift. RESULTS: Large beads successfully captured and released adSCs from rat adipose, which were characterised using a combination of microscopy, flow cytometry and PCR. The resultant purified cell population retains minimal capture artefact facilitating autologous reperfusion or application in in vitro models. CONCLUSION: Although evidenced here for adSCs, this approach provides a technological advance at a platform level; whereby it can be applied to isolate any cell population for which there is a characterised surface antigen.

  7. 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…

  8. 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.

  9. Communication protocol conversion platform based on OPC technology%基于OPC技术的通信协议转换平台

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

      在通信领域,OPC技术满足了现场设备与操作系统之间的通信要求,把现场的数据转化成统一的、规范的OPC数据,有利于科学集中地管理通信数据。文章在OPC技术的基础上,探究其在通信协议转换平台中的实践应用。%OPC technology has meet the communication demand between site equipment and operating system in the communications field,changing spot data into unitive and normative OPC data is of benefit to administrate communication data intensively.The applica-tion of the OPC technology in the communication protocol conversion platform is discussed in this paper.

  10. Optical materials technology for energy efficiency and solar energy conversion VI; Proceedings of the Meeting, San Diego, CA, Aug. 18, 19, 1987

    Science.gov (United States)

    Lampert, Carl M.

    1987-01-01

    Recent advances in optical materials for energy conversion are discussed in reviews and reports. Sections are devoted to transparent IR reflectors and large-area deposition technology; optical switching materials; holographic films and reflector technology; and absorbers, photovoltaics, and solar materials. Topics addressed include bendable Ag-based low-emissivity coating on glass, plasma oxidation of Ag and Zn in low-emissivity stacks, smart window coatings, improved colored-state reflectivity in lithiated WO3 films, photochromic and thermochromic pigments for solar absorbing-reflecting coatings, the design and optimization of holographic solar concentrators, the properties of black cobalt coatings, and interface states and Fermi-level pinning in CdSe thin-film solar cells.

  11. Implementation of Performance Assessment in STEM (Science, Technology, Engineering, Mathematics) Education to Detect Science Process Skill

    Science.gov (United States)

    Septiani, A.; Rustaman, N. Y.

    2017-02-01

    A descriptive study about the implementation of performance assessment in STEM based instruction was carried out to investigate the tenth grade of Vocational school students’ science process skills during the teaching learning processes. A number of tenth grade agriculture students was involved as research subjects selected through cluster random sampling technique (n=35). Performance assessment was planned on skills during the teaching learning process through observation and on product resulted from their engineering practice design. The procedure conducted in this study included thinking phase (identifying problem and sharing idea), designing phase, construction phase, and evaluation phase. Data was collected through the use of science process skills (SPS) test, observation sheet on student activity, as well as tasks and rubrics for performance assessment during the instruction. Research findings show that the implementation of performance assessment in STEM education in planting media could detect students science process skills better from the observation individually compared through SPS test. It was also found that the result of performance assessment was diverse when it was correlated to each indicator of SPS (strong and positive; weak and positive).

  12. 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.

  13. 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.

  14. STEM Education

    Science.gov (United States)

    Xie, Yu; Fang, Michael; Shauman, Kimberlee

    2015-01-01

    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. PMID:26778893

  15. Conversion disorder

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000954.htm Conversion disorder To use the sharing features on this page, please enable JavaScript. Conversion disorder is a mental condition in which a person ...

  16. 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.

  17. Environmental remediation and conversion of carbon dioxide (CO(2)) into useful green products by accelerated carbonation technology.

    Science.gov (United States)

    Lim, Mihee; Han, Gi-Chun; Ahn, Ji-Whan; You, Kwang-Suk

    2010-01-01

    This paper reviews the application of carbonation technology to the environmental industry as a way of reducing carbon dioxide (CO(2)), a green house gas, including the presentation of related projects of our research group. An alternative technology to very slow natural carbonation is the co-called 'accelerated carbonation', which completes its fast reaction within few hours by using pure CO(2). Carbonation technology is widely applied to solidify or stabilize solid combustion residues from municipal solid wastes, paper mill wastes, etc. and contaminated soils, and to manufacture precipitated calcium carbonate (PCC). Carbonated products can be utilized as aggregates in the concrete industry and as alkaline fillers in the paper (or recycled paper) making industry. The quantity of captured CO(2) in carbonated products can be evaluated by measuring mass loss of heated samples by thermo-gravimetric (TG) analysis. The industrial carbonation technology could contribute to both reduction of CO(2) emissions and environmental remediation.

  18. Environmental Remediation and Conversion of Carbon Dioxide (CO2 into Useful Green Products by Accelerated Carbonation Technology

    Directory of Open Access Journals (Sweden)

    Kwang-Suk You

    2010-01-01

    Full Text Available This paper reviews the application of carbonation technology to the environmental industry as a way of reducing carbon dioxide (CO2, a green house gas, including the presentation of related projects of our research group. An alternative technology to very slow natural carbonation is the co-called ‘accelerated carbonation’, which completes its fast reaction within few hours by using pure CO2. Carbonation technology is widely applied to solidify or stabilize solid combustion residues from municipal solid wastes, paper mill wastes, etc. and contaminated soils, and to manufacture precipitated calcium carbonate (PCC. Carbonated products can be utilized as aggregates in the concrete industry and as alkaline fillers in the paper (or recycled paper making industry. The quantity of captured CO2 in carbonated products can be evaluated by measuring mass loss of heated samples by thermo-gravimetric (TG analysis. The industrial carbonation technology could contribute to both reduction of CO2 emissions and environmental remediation.

  19. 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.

  20. 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…

  1. 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…

  2. What Motivates High-School Students to Pursue STEM Careers? The Influence of Public Attitudes towards Science and Technology in Comparative Perspective

    Science.gov (United States)

    Han, Seong Won

    2017-01-01

    This study examines the degree of association between students' STEM occupational expectations and between-country differences in public attitudes toward science and technology (S&T). This study focuses on public attitudes among two different populations: students and adults. Three-level Hierarchical Generalised Linear Models are employed to…

  3. 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…

  4. 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

  5. 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

  6. A 2-GHz Low-Power Down-Conversion Mixer in 0.18-μm CMOS Technology

    Science.gov (United States)

    Chen, Jun-Da; Lin, Zhi-Ming; Row, Jeen-Sheen

    A low-voltage and low-power RF mixer for WCDMA applications is presented. The paper presents a novel topology mixer that leads to a better performance in terms of isolation and power consumption for low supply voltage. The measuring results of the proposed mixer achieve: 7dB power conversion gain, 10.4dB double side band (DSB) noise figure, -2dBm input third-order intercept point (IIP3), and the total dc power consumption of this mixer including output buffers is 2.2mW from a 1V supply voltage. The current output buffer is about 1.96mW, the excellent LO-RF, LO-IF and RF-IF isolation achieved up to 49dB, 39.5dB and 57.3dB, respectively.

  7. Enhancing conversation skills in children with autism via video technology. Which is better, "self" or "other" as a model?

    Science.gov (United States)

    Sherer, M; Pierce, K L; Paredes, S; Kisacky, K L; Ingersoll, B; Schreibman, L

    2001-01-01

    The present study was designed to compare the efficacy of "self" versus "other" video-modeling interventions. Five children with autism ranging in age from 4 to 11 were taught to answer a series of conversation questions in both self and other video-modeled conditions. Results were evaluated using a combination of a multiple baseline and alternating treatments design. Three out of the five participants performed at levels of 100% accuracy at posttreatment. Results indicated no overall difference in rate of task acquisition between the two conditions, implying that children who were successful at learning from video in general, learned equally as well via both treatment approaches. Anecdotal evidence suggested that participants who were successful with video treatment had higher visual learning skills than children who were unsuccessful with this approach. Results are discussed in terms of a visual learning model for children with autism.

  8. 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.

  9. 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.

  10. Technology and economics of conversion of cellulose (wood) and corn starch to sugars, alcohol and yeast. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Wolnak, B.

    1978-08-01

    The present status of the technology and economics for the production of glucose, alcohol, and yeast from cellulose (wood), corn starch, and molasses is analyzed. The basic processes for producing glucose and the factors affecting the economics of its production are reviewed. The costs of producing ethanol and yeast from the glucose are derived. Market availability of glucose, ethanol, and yeast is surveyed. (JSR)

  11. Predictability of conversation partners

    CERN Document Server

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

    2011-01-01

    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, Song et al. (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 close sensor nodes. We find t...

  12. 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

  13. 技术学习与企业技术能力链条:知识转化整合的作用%Technological Learning and Technological Capability Chain:the Impact of Knowledge Conversion and Integration

    Institute of Scientific and Technical Information of China (English)

    彭纪生; 王秀江

    2014-01-01

    借鉴知识管理、组织学习等研究成果,提出并从理论上论证了一个整合性研究框架,揭示从技术学习上升到技术能力的演进过程。研究表明:技术能力演进需经过知识转化整合这一中介机制;在动态环境和知识转化整合过程中,即兴学习起着调节作用。研究成果为实证提供了新的研究命题和研究视角,丰富与发展了企业技术能力理论。%Based on the latest research on knowledge management and organizational learning ,a new integrative conceptual model is proposed to reveal the process through w hich technological learning transforms into the enterprises'technological capability .The study suggests the mediating role of knowledge conversion and integration in the development of techno-logical capability .And in the dynamic environment ,the effect of technological learning on technological capability is mod-erated by the improvisational learning .The findings provide new points of view to the research on technological capability theories .

  14. Progress of research and technology in conversion and utilization of carbon dioxide%CO2的绿色利用技术研究进展

    Institute of Scientific and Technical Information of China (English)

    王文珍; 张生琦; 倪炳华; 屈撑囤; 黄风林; 黄俊; 王丽莎

    2013-01-01

      近年来 CO2的综合利用越来越引起人们的重视。本文介绍了近年来通过化学途径实现CO2资源化利用的研究方向及进展,并报道了最新的研究技术和成果。通过适当的化学反应,CO2可以转化为液体燃料、甲醇、碳酸酯类等高附加值的产品,还可通过 CH4–CO2催化重整制成合成气来制备乙烯或含氧化合物等。另外,本文还介绍了其它新型 CO2化学利用技术,如通过合理设计的化学肺可将 CO2直接转换为氧气,利用太阳能、电能和生物微藻技术实现CO2向有用化学品的转化以及作为新型储氢材料的研究利用进展。%This paper reviewed and analyzed the progress on research and technology of conversion and utilization of CO2 by chemical route in recent years. CO2 can be converted into liquid fuel, methanol,carbonates,and other high value products through proper chemical reactions. CO2 can also be converted to olefin or oxygen-containing compounds through the process of CO2 – Methane synthesis. Other new technologies of CO2 utilization,including direct conversion of CO2 into oxygen through rational designed chemical lungs,conversion of CO2 into useful chemicals by solar energy, electricity and biological microalgae technologies,and progress of CO2 utilization as new hydrogen storage materials.

  15. Tenogenic induction of equine mesenchymal stem cells by means of growth factors and low-level laser technology.

    Science.gov (United States)

    Gomiero, Chiara; Bertolutti, Giulia; Martinello, Tiziana; Van Bruaene, Nathalie; Broeckx, Sarah Y; Patruno, Marco; Spaas, Jan H

    2016-03-01

    Tendons regenerate poorly due to a dense extracellular matrix and low cellularity. Cellular therapies aim to improve tendon repair using mesenchymal stem cells and tenocytes; however, a current limitation is the low proliferative potential of tenocytes in cases of severe trauma. The purpose of this study was to develop a method useful in veterinary medicine to improve the differentiation of Peripheral Blood equine mesenchymal stem cells (PB-MSCs) into tenocytes. PB-MSCs were used to study the effects of the addition of some growth factors (GFs) as TGFβ3 (transforming growth factor), EGF2 (Epidermal growth factor), bFGF2 (Fibroblast growth factor) and IGF-1 (insulin-like growth factor) in presence or without Low Level Laser Technology (LLLT) on the mRNA expression levels of genes important in the tenogenic induction as Early Growth Response Protein-1 (EGR1), Tenascin (TNC) and Decorin (DCN). The singular addition of GFs did not show any influence on the mRNA expression of tenogenic genes whereas the specific combinations that arrested cell proliferation in favour of differentiation were the following: bFGF2 + TGFβ3 and bFGF2 + TGFβ3 + LLLT. Indeed, the supplement of bFGF2 and TGFβ3 significantly upregulated the expression of Early Growth Response Protein-1 and Decorin, while the use of LLLT induced a significant increase of Tenascin C levels. In conclusion, the present study might furnish significant suggestions for developing an efficient approach for tenocyte induction since the external administration of bFGF2 and TGFβ3, along with LLLT, influences the differentiation of PB-MSCs towards the tenogenic fate.

  16. 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)

  17. Great expectations: autism spectrum disorder and induced pluripotent stem cell technologies.

    Science.gov (United States)

    Liu, Emily Yang; Scott, Christopher Thomas

    2014-04-01

    New applications of iPSC technology to research on complex idiopathic conditions raise several important ethical and social considerations for potential research participants and their families. In this short review, we examine these issues through the lens of emerging research on autism spectrum disorder (ASD). We begin by describing the current state of iPSC technology in research on ASD. Then we discuss how the social history of and current controversies in autism research combined with the emergence of autism-specific iPSC biobanks indicate an urgent need for researchers to clearly communicate the limitations and possibilities of iPSC research to ensure research participants have the ability to provide fully informed, voluntary consent. We conclude by offering recommendations to bolster informed consent for research involving iPSC biobanks, both in the specific context of ASD and more broadly.

  18. Comparative investigation of the detective quantum efficiency of direct and indirect conversion detector technologies in dedicated breast CT.

    Science.gov (United States)

    Kuttig, Jan D; Steiding, Christian; Kolditz, Daniel; Hupfer, Martin; Karolczak, Marek; Kalender, Willi A

    2015-06-01

    To investigate the dose saving potential of direct-converting CdTe photon-counting detector technology for dedicated breast CT. We analyzed the modulation transfer function (MTF), the noise power spectrum (NPS) and the detective quantum efficiency (DQE) of two detector technologies, suitable for breast CT (BCT): a flat-panel energy-integrating detector with a 70 μm and a 208 μm thick gadolinium oxysulfide (GOS) and a 150 μm thick cesium iodide (CsI) scintillator and a photon-counting detector with a 1000 μm thick CdTe sensor. The measurements for GOS scintillator thicknesses of 70 μm and 208 μm delivered 10% pre-sampled MTF values of 6.6 mm(-1) and 3.2 mm(-1), and DQE(0) values of 23% and 61%. The 10% pre-sampled MTF value for the 150 μm thick CsI scintillator 6.9 mm(-1), and the DQE(0) value was 49%. The CdTe sensor reached a 10% pre-sampled MTF value of 8.5 mm(-1) and a DQE(0) value of 85%. The photon-counting CdTe detector technology allows for significant dose reduction compared to the energy-integrating scintillation detector technology used in BCT today. Our comparative evaluation indicates that a high potential dose saving may be possible for BCT by using CdTe detectors, without loss of spatial resolution. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  19. Development of 3D in vitro platform technology to engineer mesenchymal stem cells

    OpenAIRE

    Hosseinkhani H; Hong P; Yu D; Chen Y.; Ickowicz D; Farber I; Domb AJ

    2012-01-01

    Hossein Hosseinkhani,1 Po-Da Hong,1 Dah-Shyong Yu,2 Yi-Ru Chen,3 Diana Ickowicz,4 Ira-Yudovin Farber,4 Abraham J Domb41Graduate Institute of Biomedical Engineering, National Taiwan University of Science and Technology (TAIWANTECH), 2Nanomedicine Research Center, National Defense Medical Center, Taipei, Taiwan, 3Department of Biomedical Engineering, National Yang-Ming University, Taipei, Taiwan, 4Institute of Drug Research, The Center for Nanoscience and Nanotechnology, School of Pharmacy-Facu...

  20. Optical materials technology for energy efficiency and solar energy conversion VII; Proceedings of the Meeting, Hamburg, Federal Republic of Germany, Sept. 19-21, 1988

    Science.gov (United States)

    Granqvist, Claes G.; Lampert, Carl M.

    Various papers on optical materials technology for energy efficiency and solar energy conversion are presented. Individual topics addressed include: nonlinear optical effects in organic molecules and polymers, optical and electrical properties of amorphous Li(x)WO3 films, electrochromism in sputtered vanadium pentoxide, characterization of nickel oxide electrochromic films, radiative cooling with pigmented polyethylene foils, plasma-film interactions in RF sputtered a-Si:H and a-Ge:H, metal oxyfluoride coatings for energy-efficient windows, fatigue-resistant photochromic plastics, evaporated VO(x) thin films, electrochromism in nickel oxide films, system design for high-rate deposition of indium oxide solar coatings, performance and bandwidth analysis of holographic solar reflectors, laser and spectroscopic characterization of thin films, high-efficiency collectors for solar energy applications, influence of surface roughness on the optical properties of cermet coatings, and sputtered aluminum composite selective absorbing surfaces.

  1. Glycogen synthase kinase 3 (GSK3)-inhibitor SB216763 promotes the conversion of human umbilical cord mesenchymal stem cells into neural precursors in adherent culture.

    Science.gov (United States)

    Gao, Liyang; Zhao, Mingyan; Li, Peng; Kong, Junchao; Liu, Zhijun; Chen, Yonghua; Huang, Rui; Chu, Jiaqi; Quan, Juanhua; Zeng, Rong

    2017-01-01

    The ability to generate neural progenitor cells from human umbilical cord mesenchymal stem cells (hUC-MSCs) has provided an option to treat neurodegenerative diseases. To establish a method for this purpose, we characterized the early neural markers of hUC-MSCs-derived cells under different conditions. We found that neither the elimination of signals for alternative fate nor N2 supplement was sufficient to differentiate hUC-MSCs into neural precursor cells, but the GSK3 inhibitor SB216763 could promote an efficient neural commitment of hUC-MSCs. The results indicated that Wnt/β-catenin might play an important role during the early neural differentiation of hUC-MSCs. Here, we report a method for hUC-MSCs to commit efficiently into a neural fate within a short period of time. This protocol provides an efficient method for hUC-MSCs-based neural regeneration.

  2. 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.

  3. Conversational Narcissism.

    Science.gov (United States)

    Vangelisti, Anita L.; And Others

    1990-01-01

    Examines narcissistic communication and the ways it is exhibited in everyday conversation. Identifies the following behavioral referents: boasting, refocusing the topic of conversation on the self, exaggerating hand and body movements, using a loud tone of voice, and "glazing over" when others speak. Suggests that conversational…

  4. Contentious Conversations

    Science.gov (United States)

    Zuidema, Leah A.

    2011-01-01

    The idea of joining a conversation through reading and writing is not new; in his 1941 book "The Philosophy of Literary Form: Studies in Symbolic Action," Kenneth Burke suggests that the acts of reading and writing are like entering a parlor where others are already conversing. The author explores the place of professional debate within NCTE and…

  5. 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.

  6. 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.

  7. Application of Hydrogen Technologies for Increasing the Operating Characteristic of Stem of Hip Implant Made of Titanium Alloy, Procured By Mold Castings

    Directory of Open Access Journals (Sweden)

    Skvortsova SV

    2016-11-01

    Full Text Available This work deals with the possibility of using the thermo hydrogen technology in the process of manufacturing the stem of hip implant made of titanium alloy, procured by mold castings. The influence of modes of thermo hydrogen processing on the transformation of the cast structure and mechanical properties of mold castings is analyzed in this work. It is shown that the use of thermo hydrogen processing ensures good physical and chemical contact and lets substantially increase the adhesion strength of Osseo integrating porous coating made of unalloyed titanium with titanium alloy VT6 (Ti-6-4 surface of the stem of hip implant. It identifies the elements of the processing technology of the implant elements, allowing to obtain products correspond to the international standard is identified in the work.

  8. 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.

  9. Snow snakes and science agency: Empowering American Indian students through a culturally-based science, technology, engineering, and mathematics (STEM) curriculum

    Science.gov (United States)

    Miller, Brant Gregory

    Mainstream curricula have struggled to provide American Indian students with meaningful learning experiences. This research project studied a novel approach to engaging students with science, technology, engineering, and mathematics (STEM) content through a culturally-based context. The traditional American Indian game of Snow Snakes (shushumeg in Ojibwe) presented a highly engaging context for delivering STEM content. Through the engaging context of snow snakes, the designed STEM curriculum explicitly applied mathematics (scaling and data), and science (force and motion) to an engineering prototype iteration that used available materials and tools (technology) for success. It was hypothesized that by engaging students through the carefully integrated STEM curriculum, driven by the culturally based context of snow snakes, students would exhibit an increase in science agency and achievement. The overarching research question explored for this study was: How does a culturally-based and integrated STEM curriculum impact student's science agency? Associated sub-questions were: (1) What does science agency look like for 6th grade students? (2) What key experiences are involved in the development of science agency through a culturally-based STEM curriculum context? And (3) What are the impacts on the community associated with the implementation of a culturally-based STEM curriculum? A case study research design was implemented for this research. Yin (2003) defines a case study as investigating a phenomenon (e.g. science agency) which occurs within authentic contexts (e.g. snow snakes, Adventure Learning, and Eagle Soaring School) especially when the boundaries between phenomenon and context are unclear. For this case study Eagle Soaring School acted as the bounded case with students from the 6th grade class representing the embedded units. Science agency was the theoretical framework for data analysis. Major findings were categorized as science and STEM learning, agency

  10. 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

    2016-03-01

    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.

  11. 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.

  12. Multilevel Structural Equation Models for Investigating the Effects of Computer-Based Learning in Math Classrooms on Science Technology Engineering and Math (STEM) Major Selection in 4-Year Postsecondary Institutions

    Science.gov (United States)

    Lee, Ahlam

    2017-01-01

    Background/Context: Because of the growing concern over the decline of bachelor degree recipients in the disciplines of science, technology, engineering, and math (STEM) in the U.S., several studies have been devoted to identifying the factors that affect students' STEM major choices. A majority of these studies have focused on factors relevant to…

  13. Solar energy conversion

    OpenAIRE

    Crabtree, George W.; Lewis, Nathan S.

    2007-01-01

    If solar energy is to become a practical alternative to fossil fuels, we must have efficient ways to convert photons into electricity, fuel, and heat. The need for better conversion technologies is a driving force behind many recent developments in biology, materials, and especially nanoscience.

  14. 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…

  15. 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…

  16. Conversion Disorder

    Science.gov (United States)

    ... Recent significant stress or emotional trauma Being female — women are much more likely to develop conversion disorder Having a mental health condition, such as mood or anxiety disorders, dissociative disorder or certain personality disorders Having ...

  17. 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…

  18. 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…

  19. Strategic conversation

    Directory of Open Access Journals (Sweden)

    Nicholas Asher

    2013-08-01

    Full Text Available Models of conversation that rely on a strong notion of cooperation don’t apply to strategic conversation — that is, to conversation where the agents’ motives don’t align, such as courtroom cross examination and political debate. We provide a game-theoretic framework that provides an analysis of both cooperative and strategic conversation. Our analysis features a new notion of safety that applies to implicatures: an implicature is safe when it can be reliably treated as a matter of public record. We explore the safety of implicatures within cooperative and non cooperative settings. We then provide a symbolic model enabling us (i to prove a correspondence result between a characterisation of conversation in terms of an alignment of players’ preferences and one where Gricean principles of cooperative conversation like Sincerity hold, and (ii to show when an implicature is safe and when it is not. http://dx.doi.org/10.3765/sp.6.2 BibTeX info

  20. Glial cell derived neurotrophic factor induces spermatogonial stem cell marker genes in chicken mesenchymal stem cells.

    Science.gov (United States)

    Boozarpour, Sohrab; Matin, Maryam M; Momeni-Moghaddam, Madjid; Dehghani, Hesam; Mahdavi-Shahri, Naser; Sisakhtnezhad, Sajjad; Heirani-Tabasi, Asieh; Irfan-Maqsood, Muhammad; Bahrami, Ahmad Reza

    2016-06-01

    Mesenchymal stem cells (MSCs) are known with the potential of multi-lineage differentiation. Advances in differentiation technology have also resulted in the conversion of MSCs to other kinds of stem cells. MSCs are considered as a suitable source of cells for biotechnology purposes because they are abundant, easily accessible and well characterized cells. Nowadays small molecules are introduced as novel and efficient factors to differentiate stem cells. In this work, we examined the potential of glial cell derived neurotrophic factor (GDNF) for differentiating chicken MSCs toward spermatogonial stem cells. MSCs were isolated and characterized from chicken and cultured under treatment with all-trans retinoic acid (RA) or glial cell derived neurotrophic factor. Expression analysis of specific genes after 7days of RA treatment, as examined by RT-PCR, proved positive for some germ cell markers such as CVH, STRA8, PLZF and some genes involved in spermatogonial stem cell maintenance like BCL6b and c-KIT. On the other hand, GDNF could additionally induce expression of POU5F1, and NANOG as well as other genes which were induced after RA treatment. These data illustrated that GDNF is relatively more effective in diverting chicken MSCs towards Spermatogonial stem cell -like cells in chickens and suggests GDNF as a new agent to obtain transgenic poultry, nevertheless, exploitability of these cells should be verified by more experiments.

  1. 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 ...

  2. Direct Conversion of Energy

    Energy Technology Data Exchange (ETDEWEB)

    Corliss, William R

    1964-01-01

    Topics include: direct versus dynamic energy conversion; laws governing energy conversion; thermoelectricity; thermionic conversion; magnetohydrodynamic conversion; chemical batteries; the fuel cell; solar cells; nuclear batteries; and advanced concepts including ferroelectric conversion and thermomagnetic conversion.

  3. 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.

  4. 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.

  5. 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.

  6. Novel Method To Differentiate Human Embryonic Stem Cells Into Dopaminergic Nerve Cells | NCI Technology Transfer Center | TTC

    Science.gov (United States)

    The National Institute on Drug Abuse's Development and Plasticity Section is seeking statements of capability or interest from parties interested in collaborative research to further develop, evaluate, or commercialize novel methods to differentiate human embryonic stem cells into dopaminergic nerve cells. The invention described here is a novel method of differentiating human embryonic stem cells (hESCs) into dopaminergic nerve cells, which is preferable to the currently available dopaminergic differentiation techniques.

  7. 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.

  8. Power electronics advanced conversion technologies

    CERN Document Server

    Luo, Fang Lin

    2010-01-01

    Introduction Symbols and Factors Used in This Book AC/DC Rectifiers DC/DC Converters DC/AC Inverters AC/AC Converters AC/DC/AC and DC/AC/DC Converters Uncontrolled AC/DC Converters Single-Phase Half-Wave Converters Single-Phase Full-Wave Converters Three-Phase Half-Wave Converters Six-Phase Half-Wave Converters Three-Phase Full-Wave Converters Multiphase Full-Wave Converters Controlled AC/DC Converters Single-Phase Half-Wave Controlled Converters Single-Phase Full-Wave Controlled Converters Three-Phase Half-Wave Controlled Rectifiers Six-Phase Half-Wave Controlled Rectifiers Three-Phase Full-W

  9. 激光频率上转换回波信号探测技术研究%Echo Signal Detection Technology of Laser Frequency Up-conversion

    Institute of Scientific and Technical Information of China (English)

    滕岳; 吕勇; 陈青山; 牛春晖; 刘力双

    2016-01-01

    Frequency conversion characteristics, produced by interact between laser and the object, are of great significance for target detection. The echo signal of frequency up-conversion has weak strength, pulse stretching, phase shift characteristics etc. According to this echo feature, we use the PIN photodiode as detector, and extract echo signal using lock-in amplification technology. With the help of the preamplifier circuit and AC signal amplifier circuit, the transformation and amplification of echo signal can be achieved, as well as phase sensitive detector, which is used to realize echo signal extraction. Echo detection system is set up and experimental tests show that detection system based on lock-in amplifier can suppress noise signal, as a consequence, the system can extract echo signal from background of big noise. When target at 1.5 meters in front of detection system, the output signal-noise ratio (SNR) of the system is 16.9 dB.%激光与物体相互作用产生的频率转换特性,对于目标探测具有重要的意义。频率上转换回波信号具有强度弱、脉冲展宽、有相移等特性。根据这种回波特性,论文以PIN光电二极管为探测器件,采用锁定放大技术进行回波信号检测。通过前置放大电路、交流信号放大电路完成回波信号的转换放大,运用相敏检波器实现回波信号提取,并搭建了回波探测系统。实验测试表明,基于锁定放大器的探测系统能够抑制杂波信号,从强噪声背景中提取有效回波信号,针对探测系统前方1.5 m处的探测靶标,系统的输出信噪比为16.9 dB。

  10. 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)

  11. 香蕉假茎纤维造纸技术的研究%Study on Paper Making Technology of Banana Stem Fiber

    Institute of Scientific and Technical Information of China (English)

    陈致水; 李粤; 梁栋; 王娟

    2011-01-01

    [Objective] The aim was to study paper making technology of banana stem fiber. [ Method] The paper quality, paper output, cost and investment on raw material base were analyzed. [ Result ] Paper produced by banana stem fiber was durable without acid substance, the toughness is 30 times more than common paper. Compared with other plant fibers, paper making technology by banana stem fiber has its own advantages at cost, environment etc. [Conclusion] With banana stem as paper making material has profound development value and application prospect.%[目的]对香蕉假茎纤维造纸技术进行研究.[方法]分别对纸质、出纸率、成本、原料基地投资进行分析.[结果]从香蕉假茎中提取的纤维制成的纸张不含酸性物质,很耐用,韧度是一般纸张的30倍,能防火、吸油却不透水;与其他植物纤维相比,香蕉假茎纤维虽然纤维素含量中等,但综合成本、环境各方面的因素,香蕉假茎纤维造纸技术具有一定优势.[结论]香蕉假茎作为造纸原料,具有很大的开发价值和应用前景.

  12. 变频调速技术对静叶可调轴流风机结构设计的影响%Influence of Frequency Conversion Technology on the Structure Design of Axial Fan with Static Adjustable Vanes

    Institute of Scientific and Technical Information of China (English)

    邓辉; 王吉珍; 胡灿

    2013-01-01

      针对静叶可调轴流风机采用变频调速的运行特点,从引风机结构方面进行分析,介绍风机加装变频调速装置后对风机结构的影响及解决方法。%Aiming at the operating characteristic of axial fan with static adjustable vanes adopting frequency conversion technology, this paper has analyzed the structure of fan and introduced the influence of frequency conversion equipment installed on the fan’ s structure and the solving methods.

  13. Induced neural stem cells as a means of treatment in Huntington's disease.

    Science.gov (United States)

    Choi, Kyung-Ah; Hong, Sunghoi

    2017-08-09

    Huntington's disease (HD) is an inherited neurodegenerative disease characterized by chorea, dementia, and depression caused by progressive nerve cell degeneration, which is triggered by expanded CAG repeats in the huntingtin (Htt) gene. Currently, there is no cure for this disease, nor is there an effective medicine available to delay or improve the physical, mental, and behavioral severities caused by it. Areas covered: In this review, the authors describe the use of induced neural stem cells (iNSCs) by direct conversion technology, which offers great advantages as a therapeutic cell type to treat HD. Expert opinion: Cell conversion of somatic cells into a desired stem cell type is one of the most promising treatments for HD because it could be facilitated for the generation of patient-specific neural stem cells. The induced pluripotent stem cells (iPSCs) have a powerful potential for differentiation into neurons, but they may cause teratoma formation due to an undifferentiated pluripotent stem cell after transplantation Therefore, direct conversion of somatic cells into iNSCs is a promising alternative technology in regenerative medicine and the iNSCs may be provided as a therapeutic cell source for Huntington's disease.

  14. Conversational Telugu.

    Science.gov (United States)

    Beinstein, Judith; And Others

    The purpose of this text is to develop elementary conversational skills in Telugu. The language materials consist of four types of language learning activities. The first, and most predominant, is the unit microwave cycle. These cycles divide the learning process into two basic phases, the first of which involves mimicry, memorization, and…

  15. Conversion Disorder

    National Research Council Canada - National Science Library

    Fisher, Robert S; Stonnington, Cynthia M; Barry, John J

    2006-01-01

    ... to proceed after establishing a diagnosis of conversion disorder. Case Presentation "Ms. A," a 53-year-old left-handed woman, was admitted to our epilepsy monitoring unit for evaluation of a 4-month history of tremors, head bobbing, and episodic loss of awareness. The onset of these symptoms was 1 week after she had visited an emergency department...

  16. Technology for Preparing Black Conversion Film on Aluminum Alloys and Properties of the Conversion Coating%铝合金表面黑色化学转化工艺及膜层耐蚀性能

    Institute of Scientific and Technical Information of China (English)

    王爱荣; 陶建中; 马春全

    2009-01-01

    Black chemical conversion film was prepared on the surface of Al alloy.The corrosion resistance of the chemical conversion film was evaluated by conducting dropping test and immersion test and measuring polarization curve as well.The morphology and elemental composition of the chemical conversion film were analyzed by means of scanning electron microscopy and energy dispersive X-ray analysis.Results show that the chemical conversion film on Al alloy surface looks beautifully black and has good corrosion resistance,mainly consisting of the oxides of Al,Co and Mn.%采用化学氧化着黑色法制备了铝合金化学转化膜,用点滴、浸泡试验及电化学极化曲线评价了膜的耐蚀性能,利用扫描电子显微镜(SEM)、能量散射谱(EDS)观察了化学转化膜的表面形貌,测定了其元素组成.结果表明:转化膜具有较高的耐蚀性和美观的黑色外表,主要由铝、钴和锰的各种氧化物组成.

  17. 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

  18. 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.

  19. 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…

  20. 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…

  1. Conversion Disorder

    Directory of Open Access Journals (Sweden)

    Yacov Rofé

    2013-11-01

    Full Text Available Conversion disorder remains a mystery that has only become more complicated with the decline of the scientific status of psychoanalysis (e.g., Piper, Lillevik, & Kritzer, 2008; Rofé, 2008 and recent neurological findings suggest that this behavior is controlled by biological mechanisms (van Beilen, Vogt, & Leenders, 2010. Moreover, existing theories have difficulty explaining the efficacy of various interventions, such as psychoanalysis, behavior therapy, drug therapy and religious therapy. This article reviews research and clinical evidence pertaining to both the development and treatment of conversion disorder and shows that this seemingly incompatible evidence can be integrated within a new theory, the Rational-Choice Theory of Neurosis (RCTN; Rofé, 2010. Despite the striking differences, RCTN continues Freud's framework of thinking as it employs a new concept of repression and replaces the unconscious with self-deception. Moreover, it incorporates Freud's idea, implicitly expressed in his theory, that neurotic disorders are, in fact, rational behaviors.

  2. Progess in technology development for conversion of {sup 99}Mo production--BATAN's (Indonesia) conversion program, progress in the CNEA (Argentina) LEU foil/base-side process, and development of inorganic sorbents for {sup 99}Mo production.

    Energy Technology Data Exchange (ETDEWEB)

    Bakel, A. J.; Stepinski, D. C.; Vandegrift, G. F.; Leyva, A.; Gelis, A. V.; Bond, A. H.; Mayes, H.; Chemical Engineering

    2005-01-01

    Currently, nearly all of the world's supply of {sup 99}Mo is produced fiom the fissioning of {sup 235}U in targets of high-enriched uranium (HEU). Conversion of these targets to low-enriched uranium (LEU) would ease worldwide concern over the use and transport of this weapons-grade material. This paper reviews three projects: (1) the ongoing conversion of BATAN's {sup 99}Mo production process from HEU oxide targets (Cintichem processing) to LEU foil targets (Cintichem processing), (2) demonstration of LEU foil targets and base-side processing in CNEA's facility, and (3) the evaluation of two inorganic Thermoxid sorbents for Mo recovery and purification in acidic U-bearing solutions.

  3. Making STEM Connections

    Science.gov (United States)

    Stump, Sheryl L.; Bryan, Joel A.; McConnell, Tom J.

    2016-01-01

    Integrated approaches to education in science, technology, engineering, and mathematics (STEM), especially those set in the context of real-world situations, can motivate and deepen students' learning of the STEM subjects (National Academy of Engineering and National Research Council 2014). This article describes two integrated investigations used…

  4. Teaching STEM by Design

    Science.gov (United States)

    Billiar, Kristen; Hubelbank, Jeanne; Oliva, Thomas; Camesano, Terri

    2014-01-01

    Developing innovative science, technology, engineering and mathematics (STEM) curricula that elicit student excitement for learning is a continuous challenge for K-12 STEM teachers. Generating these lessons while meeting conflicting pedagogical objectives and constraints of time, content, and cost from various parties is truly a challenging task…

  5. Making the Connection: The Impact of Support Systems on Female Transfer Students in Science, Technology, Engineering, and Mathematics (STEM)

    Science.gov (United States)

    Jackson, Dimitra L.

    2013-01-01

    The availability of student support systems and mentee-mentor relationships provide effective ways to increase the representation of women in STEM areas (Creamer & Laughlin, 2005). Support systems allow students the opportunity to engage in discussion and activities with individuals, including family, faculty, staff, or administrators with…

  6. Research Progress of Spermatogonial Stem Cells Transplantation Technology%精原干细胞移植相关技术研究进展

    Institute of Scientific and Technical Information of China (English)

    刘玲; 王栋; 朱化彬; 王琛; 郝海生; 赵学明; 冯荣; 杜卫华; 秦彤; 刘岩

    2012-01-01

    The culture and transplantation ofspermatogonial stem cells(SSCs) and related researches will be significant in some fields, such as male infertility, spermatogenesis mechanism research and set-up of transgenic technology. Biological characteristics of mouse SSCs had been studied clearly. The technology system of isolating, purifying and cultivating these stem cells had been built, as well as recipient preparation and transplantation technology. However, the efficiency of these technologies is not high. Reviewing all the above technologies, not only the optimum preparation time of the stem cells can be determined, but also the technique of recipient preparation and the techniques of purification, cultivation and transplantation of SSCs will be improved. And these will also provide guidance for the future study on farm animals in this field%精原干细胞的分离培养及移植等相关技术对于雄性动物不育、精子发生机理的研究及转基因新技术的建立都具有重要意义.虽然小鼠精原干细胞的生物学特性已经研究得较为清晰,并建立了较为成熟的分离、纯化、培养技术体系,其受体制备和移植技术也较为成熟,但是,技术效率仍然很低.对小鼠精原干细胞生物学特性、分离培养及受体制备与移植方法的分析总结,将对于细胞制备最佳时机的确定、已有精原干细胞分离纯化、培养和受体准备及移植方法的改进提高起到重要的推动作用,也为今后大型动物的相关研究指明了方向.

  7. Bringing Fenton Hill into the Digital Age: Data Conversion in Support of the Geothermal Technologies Office Code Comparison Study Challenge Problems

    Energy Technology Data Exchange (ETDEWEB)

    White, Signe K.; Kelkar, Sharad M.; Brown, Don W.

    2016-03-01

    The Geothermal Technologies Office Code Comparison Study (GTO-CCS) was established by the U.S. Department of Energy to facilitate collaboration among members of the geothermal modeling community and to evaluate and improve upon the ability of existing codes to simulate thermal, hydrological, mechanical, and chemical processes associated with complex enhanced geothermal systems (EGS). The first stage of the project, which has been completed, involved comparing simulations for seven benchmark problems that were primarily designed using well-prescribed, simplified data sets. In the second stage, the participating teams are tackling two challenge problems based on the EGS research conducted in hot dry rock (HDR) at Fenton Hill, near Los Alamos, New Mexico. The Fenton Hill project, conducted by Los Alamos National Laboratory (LANL) from 1970 to 1995, was the world’s first HDR demonstration project. One of the criteria for selecting this experiment as the basis for the challenge problems was the amount and availability of data for generating model inputs. The Fenton Hill HDR system consisted of two reservoirs – an earlier Phase I reservoir tested from 1974 to 1981 and a deeper Phase II reservoir tested from 1980 to 1995. Detailed accounts of both phases of the HDR project have been presented in a number of books and reports, including a recently published summary of the lessons learned and a final report with a chronological description of the Fenton Hill project, prepared by LANL. Project documents and records have been archived and made public through the National Geothermal Data System (NGDS). Some of the data acquired from Phase II are available in electronic format readable on modern computers. These include the microseismic data from some of the important experiments (e.g. the massive hydraulic fracturing test conducted in 1983) and the injection/production wellhead data from the circulation tests conducted between 1992-1995. However, much of the data collected

  8. 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.

  9. NASA y Tú (NASA and You) - NASA's partnership with UNIVISION to promote Science, Technology, Engineering, and Math (STEM) careers among Hispanic youth

    Science.gov (United States)

    Colon-Robles, M.; Gilman, I.; Verstynen, S.; Jaramillo, R.; Bednar, S.; Shortridge, T.; Bravo, J.; Bowers, S.

    2010-12-01

    NASA is working with Univision Communications Inc. in support of the Spanish-language media outlet's initiative to improve high school graduation rates, prepare Hispanic students for college, and encourage them to pursue careers in science, technology, engineering and mathematics, or STEM, disciplines. A total of 52 Public Service Announcements (PSAs) named “Visión NASA” or “Vision: NASA” are being developed by NASA centered on current innovative technologies from all four NASA mission directorates (Science, Exploration Systems, Space Operations, and Aerodynamics). Public service announcements are being produced from scratch in both English and Spanish for a total of 26 announcements in each language. Interviews were conducted with NASA Hispanic Scientists or Engineers on the selected PSAs topics to both supply information on their subject matter and to serve as role models for Hispanic youth. Each topic selected for the PSAs has an accompanying website which includes the announcements, interviews with a Hispanic scientists or engineers, background information on the topic, and educational resources for students, parents and teachers. Products developed through this partnership will be presented including the websites of each PSA and their accompanying educational resources. The use of these educational resources for professional development, outreach and informal events, and for in-classroom uses will also be presented. This collaboration with Univision complements NASA's current education efforts to engage underrepresented and underserved students in the critical STEM fields.

  10. 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...

  11. STEM--Beyond the Acronym

    Science.gov (United States)

    Vasquez, Jo Anne

    2015-01-01

    When most educators think of STEM education, they think of fully integrated projects seamlessly combining all four disciplines--science, technology, engineering, and mathematics. Although such transdisciplinary STEM units are ideal, writes Vasquez, they are not the only way to give students valuable STEM experiences. She gives examples of two…

  12. 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.

  13. 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.

  14. 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,…

  15. Detection of Prostate Stem Cell Antigen Expression in Human Prostate Cancer Using Quantum-Dot-Based Technology

    OpenAIRE

    Stéphane Larré; Yuan Ruan; Weimin Yu; Fan Cheng; Xiaobin Zhang

    2012-01-01

    Quantum dots (QDs) are a new class of fluorescent labeling for biological and biomedical applications. In this study, we detected prostate stem cell antigen (PSCA) expression correlated with tumor grade and stage in human prostate cancer by QDs-based immunolabeling and conventional immunohistochemistry (IHC), and evaluated the sensitivity and stability of QDs-based immunolabeling in comparison with IHC. Our data revealed that increasing levels of PSCA expression accompanied advanced tumor gra...

  16. [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.

  17. 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…

  18. Research and Realization of DWG to SHP Format Conversion Technology%DWG 到 SHP 格式转换技术的研究与实现

    Institute of Scientific and Technical Information of China (English)

    肖锋; 吕宝奇; 林蒙恩

    2013-01-01

    The current surveying and mapping industry is based on topographic map database establishment with the key step of DWG to SHP format lossless conversion , especially property conversion .There is no readily available software which can realize one step conversion.Through the DWG and SHP format data structure , using VC++2005 and ObjectARX SDK development environment , secondary development on AutoCAD platform , graphics data conversion in terms of the point , line and polygon, attribute data, XData XRecord, OData, OProperty conversion , DWG to SHP format conversion is achieved , and requirements of graphics and attributes are satisfied with simple and quick operation and good application in the actual production .%当前测绘行业很多都是基于DWG地形图数据的数据库建设,生产中一个关键的环节就是DWG到SHP格式的无损转换,尤其是属性的转换。目前,没有现成的软件能一步到位地实现转换,通过对DWG和SHP格式数据结构的研究,采用VC++2005和ObjectARX SDK开发环境,在AutoCAD平台上二次开发,图形数据按点、线、面转换,属性数据分扩展数据、扩展记录、对象数据、对象特性转换,完成了DWG到SHP的格式转换,同时满足图形和属性的要求,操作简单快捷,在实际生产中取得较好的应用效果。

  19. 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

  20. Attainment of biofuel in pilot unity by using the low temperature conversion technology; Obtencao de biocombustivel em unidade piloto utilizando a tecnologia de conversao a baixa temperatura

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Roberto Guimaraes [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Engenharia Mecanica]|[Universidade Federal Fluminense, Niteroi, RJ (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica; Romeiro, Gilberto Alves; Damasceno, Raimundo Nonato [Universidade Federal Fluminense, Niteroi, RJ (Brazil). Dept. de Quimica Organica]|[Universidade Federal Fluminense, Niteroi, RJ (Brazil). Programa de Pos-Graduacao em Quimica Organica; Senra, Paulo Mauricio de Albuquerque [Light Servicos de Eletricidade S.A., Rio de Janeiro, RJ (Brazil). Gerencia de Estudos e Gestao de Geracao

    2004-07-01

    This paper refers the oil attainment in a pilot unity, trough the low temperature conversion process applied to the industrial residue generated in petrochemistry industry effluent treatment station. Physical-chemical parameters such as sulfur density content, flash point, point of fluidity and calorific power were obtained. The characterization of oil indicates the possibility in classifying as fuel oil.

  1. Roadmap on optical energy conversion

    Science.gov (United States)

    Boriskina, Svetlana V.; Green, Martin A.; Catchpole, Kylie; Yablonovitch, Eli; Beard, Matthew C.; Okada, Yoshitaka; Lany, Stephan; Gershon, Talia; Zakutayev, Andriy; Tahersima, Mohammad H.; Sorger, Volker J.; Naughton, Michael J.; Kempa, Krzysztof; Dagenais, Mario; Yao, Yuan; Xu, Lu; Sheng, Xing; Bronstein, Noah D.; Rogers, John A.; Alivisatos, A. Paul; Nuzzo, Ralph G.; Gordon, Jeffrey M.; Wu, Di M.; Wisser, Michael D.; Salleo, Alberto; Dionne, Jennifer; Bermel, Peter; Greffet, Jean-Jacques; Celanovic, Ivan; Soljacic, Marin; Manor, Assaf; Rotschild, Carmel; Raman, Aaswath; Zhu, Linxiao; Fan, Shanhui; Chen, Gang

    2016-07-01

    For decades, progress in the field of optical (including solar) energy conversion was dominated by advances in the conventional concentrating optics and materials design. In recent years, however, conceptual and technological breakthroughs in the fields of nanophotonics and plasmonics combined with a better understanding of the thermodynamics of the photon energy-conversion processes reshaped the landscape of energy-conversion schemes and devices. Nanostructured devices and materials that make use of size quantization effects to manipulate photon density of states offer a way to overcome the conventional light absorption limits. Novel optical spectrum splitting and photon-recycling schemes reduce the entropy production in the optical energy-conversion platforms and boost their efficiencies. Optical design concepts are rapidly expanding into the infrared energy band, offering new approaches to harvest waste heat, to reduce the thermal emission losses, and to achieve noncontact radiative cooling of solar cells as well as of optical and electronic circuitries. Light-matter interaction enabled by nanophotonics and plasmonics underlie the performance of the third- and fourth-generation energy-conversion devices, including up- and down-conversion of photon energy, near-field radiative energy transfer, and hot electron generation and harvesting. Finally, the increased market penetration of alternative solar energy-conversion technologies amplifies the role of cost-driven and environmental considerations. This roadmap on optical energy conversion provides a snapshot of the state of the art in optical energy conversion, remaining challenges, and most promising approaches to address these challenges. Leading experts authored 19 focused short sections of the roadmap where they share their vision on a specific aspect of this burgeoning research field. The roadmap opens up with a tutorial section, which introduces major concepts and terminology. It is our hope that the roadmap

  2. Roadmap on optical energy conversion

    Energy Technology Data Exchange (ETDEWEB)

    Boriskina, Svetlana V.; Green, Martin A.; Catchpole, Kylie; Yablonovitch, Eli; Beard, Matthew C.; Okada, Yoshitaka; Lany, Stephan; Gershon, Talia; Zakutayev, Andriy; Tahersima, Mohammad H.; Sorger, Volker J.; Naughton, Michael J.; Kempa, Krzysztof; Dagenais, Mario; Yao, Yuan; Xu, Lu; Sheng, Xing; Bronstein, Noah D.; Rogers, John A.; Alivisatos, A. Paul; Nuzzo, Ralph G.; Gordon, Jeffrey M.; Wu, Di M.; Wisser, Michael D.; Salleo, Alberto; Dionne, Jennifer; Bermel, Peter; Greffet, Jean-Jacques; Celanovic, Ivan; Soljacic, Marin; Manor, Assaf; Rotschild, Carmel; Raman, Aaswath; Zhu, Linxiao; Fan, Shanhui; Chen, Gang

    2016-06-24

    For decades, progress in the field of optical (including solar) energy conversion was dominated by advances in the conventional concentrating optics and materials design. In recent years, however, conceptual and technological breakthroughs in the fields of nanophotonics and plasmonics combined with a better understanding of the thermodynamics of the photon energy-conversion processes reshaped the landscape of energy-conversion schemes and devices. Nanostructured devices and materials that make use of size quantization effects to manipulate photon density of states offer a way to overcome the conventional light absorption limits. Novel optical spectrum splitting and photon-recycling schemes reduce the entropy production in the optical energy-conversion platforms and boost their efficiencies. Optical design concepts are rapidly expanding into the infrared energy band, offering new approaches to harvest waste heat, to reduce the thermal emission losses, and to achieve noncontact radiative cooling of solar cells as well as of optical and electronic circuitries. Light-matter interaction enabled by nanophotonics and plasmonics underlie the performance of the third- and fourth-generation energy-conversion devices, including up- and down-conversion of photon energy, near-field radiative energy transfer, and hot electron generation and harvesting. Finally, the increased market penetration of alternative solar energy-conversion technologies amplifies the role of cost-driven and environmental considerations. This roadmap on optical energy conversion provides a snapshot of the state of the art in optical energy conversion, remaining challenges, and most promising approaches to address these challenges. Leading experts authored 19 focused short sections of the roadmap where they share their vision on a specific aspect of this burgeoning research field. The roadmap opens up with a tutorial section, which introduces major concepts and terminology. It is our hope that the roadmap

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

    Science.gov (United States)

    Ramírez, Manuel; García-Castro, Javier; Melen, Gustavo J; González-Murillo, África; Franco-Luzón, Lidia

    2015-01-01

    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.

  4. 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

  5. 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

  6. Methods and technologies for surveying and forecasting the rice stem borers%水稻钻蛀性螟虫田间调查及测报技术

    Institute of Scientific and Technical Information of China (English)

    陆明星; 陆自强; 杜予州

    2014-01-01

    For a long time, the rice stem borers are main insect pest in rice. With the change of rice cultivation and climate change, the populations of the rice stem borers increase gradually, which damage the rice yield more and more seriously in recent years. Therefore, it’s very meaningful for the integrated management of the rice stem borers to investigate the dynamics scientifically and forecast accurately their trends. According to biological characteristics of Sesamia inferens (Walker), Chilo suppressalis (Walker), Scirpophaga incertulas (Walker), the surveying methods of these borers in the field were summarized. And three forecasting methods of occurrence stage were demonstrated. Moreover, some attentions during the survey were discussed. In conclusion, these methods and technologies will provide a strong foundation for the integrated management of the rice stem borers.%长期以来,水稻钻蛀性螟虫都是我国水稻上的重要害虫。近年来,随着水稻栽培制度的变更及全球性气候的变化,种群数量逐渐回升,为害日趋严重。因此,科学的调查方法和准确的预测预报,对该类害虫的综合治理具有重要意义。本文根据大螟Sesamia inferens(Walker)、二化螟Chilo suppressalis(Walker)和三化螟Scirpophaga incertulas(Walker)的生物学特性,总结了这3种水稻钻蛀性螟虫的田间调查方法;阐述了它们的发生期预测方法;探讨了在调查取样过程中的注意事项,以期为我国水稻钻蛀性螟虫的综合防治提供可靠的数据支撑。

  7. 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

  8. Expanding STEM Education | Poster

    Science.gov (United States)

    Editor’s note: This article is written as a reflection on experiential STEM education by a student who completed her Werner H. Kirsten internship in June 2015. Here, she advocates for incorporating hands-on experience into STEM curricula. If the only way for high school students to learn science, technology, engineering, and mathematics (STEM) is through textbooks, then count me out. But how then do you get students to learn STEM outside of the classroom? The focus of this article is to advocate for high school STEM education through experiential learning. Tom Freston, one of the founders and the chief executive officer (CEO) of MTV Productions, said in an interview in Men’s Journal that “innovation is taking two things that already exist and...

  9. 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. ...

  10. Whole-blastocyst culture followed by laser drilling technology enhances the efficiency of inner cell mass isolation and embryonic stem cell derivation from good- and poor-quality mouse embryos: new insights for derivation of human embryonic stem cell lines.

    Science.gov (United States)

    Cortes, J L; Sánchez, L; Catalina, P; Cobo, F; Bueno, C; Martínez-Ramirez, A; Barroso, A; Cabrera, C; Ligero, G; Montes, R; Rubio, R; Nieto, A; Menendez, P

    2008-04-01

    The optimization of human embryonic stem (hES) cell line derivation methods is challenging because many worldwide laboratories have neither access to spare human embryos nor ethical approval for using supernumerary human embryos for hES cell derivation purposes. Additionally, studies performed directly on human embryos imply a waste of precious human biological material. In this study, we developed a new strategy based on the combination of whole-blastocyst culture followed by laser drilling destruction of the trophoectoderm for improving the efficiency of inner cell mass (ICM) isolation and ES cell derivation using murine embryos. Embryos were divided into good- and poor-quality embryos. We demonstrate that the efficiency of both ICM isolation and ES cell derivation using this strategy is significantly superior to whole-blastocyst culture or laser drilling technology itself. Regardless of the ICM isolation method, the ES cell establishment depends on a feeder cell growth surface. Importantly, this combined methodology can be successfully applied to poor-quality blastocysts that otherwise would not be suitable for laser drilling itself nor immunosurgery in an attempt to derive ES cell lines due to the inability to distinguish the ICM. The ES cell lines derived by this combined method were characterized and shown to maintain a typical morphology, undifferentiated phenotype, and in vitro and in vivo three germ layer differentiation potential. Finally, all ES cell lines established using either technology acquired an aneuploid karyotype after extended culture periods, suggesting that the method used for ES cell derivation does not seem to influence the karyotype of the ES cells after extended culture. This methodology may open up new avenues for further improvements for the derivation of hES cells, the majority of which are derived from frozen, poor-quality human embryos.

  11. Part I: Minicircle vector technology limits DNA size restrictions on ex vivo gene delivery using nanoparticle vectors: Overcoming a translational barrier in neural stem cell therapy.

    Science.gov (United States)

    Fernandes, Alinda R; Chari, Divya M

    2016-09-28

    Genetically engineered neural stem cell (NSC) transplant populations offer key benefits in regenerative neurology, for release of therapeutic biomolecules in ex vivo gene therapy. NSCs are 'hard-to-transfect' but amenable to 'magnetofection'. Despite the high clinical potential of this approach, the low and transient transfection associated with the large size of therapeutic DNA constructs is a critical barrier to translation. We demonstrate for the first time that DNA minicircles (small DNA vectors encoding essential gene expression components but devoid of a bacterial backbone, thereby reducing construct size versus conventional plasmids) deployed with magnetofection achieve the highest, safe non-viral DNA transfection levels (up to 54%) reported so far for primary NSCs. Minicircle-functionalized magnetic nanoparticle (MNP)-mediated gene delivery also resulted in sustained gene expression for up to four weeks. All daughter cell types of engineered NSCs (neurons, astrocytes and oligodendrocytes) were transfected (in contrast to conventional plasmids which usually yield transfected astrocytes only), offering advantages for targeted cell engineering. In addition to enhancing MNP functionality as gene delivery vectors, minicircle technology provides key benefits from safety/scale up perspectives. Therefore, we consider the proof-of-concept of fusion of technologies used here offers high potential as a clinically translatable genetic modification strategy for cell therapy.

  12. 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,…

  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 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…

  15. 变频技术在发电厂的应用%Application of Frequency Conversion Technology in the Power Plant

    Institute of Scientific and Technical Information of China (English)

    司春生; 刘树昌

    2001-01-01

    Annual savings of electricity was 2650kWh by installation of Hitachi J300 frequency conversion speed regulations in the power plant, which has effectively prevented motors against trip caused by the fluctuation of voltage.%在电厂送风机、凝结水泵、疏水泵和除盐水泵等机组上加装了变频调速装置后,年节电265万kWh,并有效的防止了由于电压波动造成的电机跳闸。

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

    Science.gov (United States)

    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

    2014-06-01

    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 the cardiomyopathy of Barth syndrome (BTHS), a mitochondrial disorder caused by mutation of the gene encoding tafazzin (TAZ). Using BTHS iPSC-derived cardiomyocytes (iPSC-CMs), we defined metabolic, structural and functional abnormalities associated with TAZ mutation. BTHS iPSC-CMs assembled sparse and irregular sarcomeres, and engineered BTHS 'heart-on-chip' tissues contracted weakly. Gene replacement and genome editing demonstrated that TAZ mutation is necessary and sufficient for these phenotypes. Sarcomere assembly and myocardial contraction abnormalities occurred in the context of normal whole-cell ATP levels. Excess levels of reactive oxygen species mechanistically linked TAZ mutation to impaired cardiomyocyte function. Our study provides new insights into the pathogenesis of Barth syndrome, suggests new treatment strategies and advances iPSC-based in vitro modeling of cardiomyopathy.

  17. Detection of Prostate Stem Cell Antigen Expression in Human Prostate Cancer Using Quantum-Dot-Based Technology

    Directory of Open Access Journals (Sweden)

    Stéphane Larré

    2012-04-01

    Full Text Available Quantum dots (QDs are a new class of fluorescent labeling for biological and biomedical applications. In this study, we detected prostate stem cell antigen (PSCA expression correlated with tumor grade and stage in human prostate cancer by QDs-based immunolabeling and conventional immunohistochemistry (IHC, and evaluated the sensitivity and stability of QDs-based immunolabeling in comparison with IHC. Our data revealed that increasing levels of PSCA expression accompanied advanced tumor grade (QDs labeling, r = 0.732, p < 0.001; IHC, r = 0.683, p < 0.001 and stage (QDs labeling, r = 0.514, p = 0.001; IHC, r = 0.432, p = 0.005, and the similar tendency was detected by the two methods. In addition, by comparison between the two methods, QDs labeling was consistent with IHC in detecting the expression of PSCA in human prostate tissue correlated with different pathological types (K = 0.845, p < 0.001. During the observation time, QDs exhibited superior stability. The intensity of QDs fluorescence remained stable for two weeks (p = 0.083 after conjugation to the PSCA protein, and nearly 93% of positive expression with their fluorescence still could be seen after four weeks.

  18. Recombinant messenger RNA technology and its application in cancer immunotherapy, transcript replacement therapies, pluripotent stem cell induction, and beyond.

    Science.gov (United States)

    Vallazza, Britta; Petri, Sebastian; Poleganov, Marco A; Eberle, Florian; Kuhn, Andreas N; Sahin, Ugur

    2015-01-01

    In recent years, the interest in using messenger RNA (mRNA) as a therapeutic means to tackle different diseases has enormously increased. This holds true not only for numerous preclinical studies, but mRNA has also entered the clinic to fight cancer. The advantages of using mRNA compared to DNA were recognized very early on, e.g., the lack of risk for genomic integration, or the expression of the encoded protein in the cytoplasm without the need to cross the nuclear membrane. However, it was generally assumed that mRNA is just not stable enough to give rise to sufficient expression of the encoded protein. Yet, an initially small group of mRNA aficionados could demonstrate that the stability of mRNA and the efficiency, by which the encoded protein is translated, can be significantly increased by selecting the right set of cis-acting structural elements (including the 5'-cap, 5'- and 3'-untranslated regions, poly(A)-tail, and modified building blocks). In parallel, significant advances in RNA packaging and delivery have been made, extending the potential for this molecule. This paved the way for further work to prove mRNA as a promising therapeutic for multiple diseases. Here, we review the developments to optimize mRNA regarding stability, translational efficiency, and immune-modulating properties to enhance its functionality and efficacy as a therapeutic. Furthermore, we summarize the current status of preclinical and clinical studies that use mRNA for cancer immunotherapy, for the expression of functional proteins as so-called transcript (or protein) replacement therapy, as well as for induction of pluripotent stem cells.

  19. The Application of Three-level Voltage Type High Voltage Frequency Conversion Technology in Ocean Engineering Ships%三电平电压型高压变频技术在海洋工程船的应用

    Institute of Scientific and Technical Information of China (English)

    宋艳琼

    2014-01-01

    节能减排、绿色环保,变频电力驱动技术是国内外船舶上应用的发展趋势.特别体现在海洋工程船的大型施工设备和施工设备的驱动系统上.阐述了变频电力驱动技术应用于海洋工程船的优点,介绍了三电平电压型高压变频技术的发展.对三电平电压型高压变频技术进行原理简述,给出了三电平空间电压矢量控制调速系统的主电路拓扑结构,分析了三电平空间电压矢量控制算法的实现,利用MATLAB 7.0/SIMULINK 6.0进行了三电平电压型高压变频调速系统的建模和仿真.%For the purpose of energy saving and emission reduction and green environmental protection , frequency conversion electric drive technology in the world is a development trend applied in ships .Especially this is embodied in large-scale construction equipment of ocean engineering ships and the drive system to construction equipment .This paper elaborates the advantages of variable frequency electric drive technology application in ocean engineering ships , and introduces the development of three-level voltage type high voltage frequency conversion technology.Also, the author illustrates the theories of three-level voltage type high voltage frequency conversion technology , and gives the main circuit topology structure of the three-level space voltage vector control speed regulation system , and analyzes the three-level space voltage vector control algorithm implementation , and finally builds a modeling and simulation of the three-level voltage type high voltage variable frequency speed regulation system by using MATLAB 7.0/SIMULINK 6.0 modules.

  20. 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 ...

  1. 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.

  2. 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

  3. 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.

  4. 无铬磷酸盐稀土转化膜工艺研究%Study on Chromium- Free Phosphate Rare Earth Conversion Coatings Technology

    Institute of Scientific and Technical Information of China (English)

    娄淑芳; 李红玲

    2011-01-01

    常温下对6061铝合金表面转化膜进行了研究,分别讨论了Zn2+、Po3-4、F-、Fe2+、Ce3+、Cu2+对磷化膜质量的影响,同时通过正交试验和综合评定法确定出了一种不含铬的铝合金稀土磷化液的介质组成及相应的工艺参数.转化膜成分含有Zn、Fe、P、O、Ce的复合磷酸盐,结果表明:此磷化液在常温下,8 min即可在6061铝合金表面上生成一层均匀、致密、耐蚀性良好的磷化膜.该方法工艺简单,在整个工艺过程中不需要使用铬元素,对环境影响小,具有良好的应用前景.%Conversion coating on 6061 aluminum alloy surface has been studied under ordinary temperature. The effects of Zn2+ , pO34- , F-, Fe2+ , Ce3+ , Cu2+ on the quality of phosphating coating were discussed. In addition, by use of orthogonal experiment and synthetic evaluation method, the composition and corresponding process parameters of a chromium - free rare earth phosphating solution are determined. The conversion film conponent contains compound phospates of Zn, Fe, P, O, Ce. The results show that this phosphating solution at room temperature can form a uniform, dense and corrosion protective layer in 8 min on 6061 aluminum alloy surface. This method is simple, and needs no chromium element completely, with less harmful effects on environment and good application prospect.

  5. 基于太阳能辐射技术的热能转换空调制冷技术研究%Research on Cooler Air conditioner Based on Thermal Conversion of Solar Radiation Technology

    Institute of Scientific and Technical Information of China (English)

    李裕斌

    2016-01-01

    This paper presents technical approach on cooler air conditioner based on thermal conver-sion of solar radiation technology,i.e.transforming solar energy to heat energy,and use the heat energy to achieve refrigeration.We developed a new solar absorption air conditioning system based on the thermal conversion of solar radiation technology.Through verification studies,the operating characteristics of so-lar collector and heat storage system of air conditioning systems,and operating characteristics of the re-frigeration unit are verified.The experiment shows:the air conditioning system can operate continuously and stably for 8 hours.The average cooling capacity is 4 kW,and the maximum cooling capacity is 4.7 kW.The system COP average is 0.3.Therefore,this new solar absorption air conditioning system based on thermal conversion of solar radiation technology provides a feasible method to realize large scale,low cost application of solar energy.%给出了以太阳能辐射技术为基础的热能转换空调制冷技术的技术方法,即将太阳能转变成热能,使用热能进行制冷。以太阳能辐射技术的热能转换为基础,研制了新型的太阳能吸收式空调系统,并且通过实验研究,验证了该系统的集热、蓄热特性以及制冷机组的运行热性。实验表明,该空调系统可连续8 h 稳定地工作,最大制冷量可达到4.7 kW,平均值也可达到4 kW,该空调系统性能参数 COP,平均可达到0.3。因此,基于太阳能辐射技术的热能转换空调制冷技术为太阳能规模化、低成本应用提供了行之有效的新方法。

  6. Compartmental Hollow Fiber Capillary Membrane–Based Bioreactor Technology for In Vitro Studies on Red Blood Cell Lineage Direction of Hematopoietic Stem Cells

    Science.gov (United States)

    Housler, Greggory J.; Miki, Toshio; Schmelzer, Eva; Pekor, Christopher; Zhang, Xiaokui; Kang, Lin; Voskinarian-Berse, Vanessa; Abbot, Stewart; Zeilinger, Katrin

    2012-01-01

    Continuous production of red blood cells (RBCs) in an automated closed culture system using hematopoietic stem cell (HSC) progenitor cell populations is of interest for clinical application because of the high demand for blood transfusions. Previously, we introduced a four-compartment bioreactor that consisted of two bundles of hollow fiber microfiltration membranes for transport of culture medium (forming two medium compartments), interwoven with one bundle of hollow fiber membranes for transport of oxygen (O2), carbon dioxide (CO2), and other gases (forming one gas compartment). Small-scale prototypes were developed of the three-dimensional (3D) perfusion cell culture systems, which enable convection-based mass transfer and integral oxygenation in the cell compartment. CD34+ HSC were isolated from human cord blood units using a magnetic separation procedure. Cells were inoculated into 2- or 8-mL scaled-down versions of the previously designed 800-mL cell compartment devices and perfused with erythrocyte proliferation and differentiation medium. First, using the small-scale 2-mL analytical scale bioreactor, with an initial seeding density of 800,000 cells/mL, we demonstrated approximately 100-fold cell expansion and differentiation after 7 days of culture. An 8-mL laboratory-scale bioreactor was then used to show pseudocontinuous production by intermediately harvesting cells. Subsequently, we were able to use a model to demonstrate semicontinuous production with up to 14,288-fold expansion using seeding densities of 800,000 cells/mL. The down-scaled culture technology allows for expansion of CD34+ cells and stimulating these progenitors towards RBC lineage, expressing approximately 40% CD235+ and enucleation. The 3D perfusion technology provides an innovative tool for studies on RBC production, which is scalable. PMID:21933020

  7. 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.

  8. The Investigation of Sudden Arrhythmic Death Syndrome (SADS – the current approach to family screening and the future role of genomics & stem cell technology

    Directory of Open Access Journals (Sweden)

    Vishal eVyas

    2013-09-01

    Full Text Available SADS is defined as sudden death under the age of 40 years old in the absence of structural heart disease. Family screening studies are able to identify a cause in up to 50% of cases-most commonly long QT syndrome, Brugada and early repolarisation syndrome, and catecholaminergic polymorphic ventricular tachycardia using standard clinical screening investigations including pharmacological challenge testing. These diagnoses may be supported by genetic testing which can aid cascade screening and may help guide management. In the current era it is possible to undertake molecular autopsy provided suitable samples of DNA can be obtained from the proband. With the evolution of rapid sequencing techniques it is possible to sequence the whole exome for candidate genes. This major advance offers the opportunity to identify novel causes of lethal arrhythmia but also poses the challenge of managing the volume of data generated and evaluating variants of unknown significance. The emergence of induced pluripotent stem cell technology could enable evaluation of the electrophysiological relevance of specific ion channel mutations in the proband or their relatives and will potentially enable screening of idiopathic ventricular fibrillation survivors combining genetic and electrophysiological studies in derived myocytes. This also could facilitate the assessment of personalised preventative pharmacological therapies. This review will evaluate the current screening strategies in SADS families, the role of molecular autopsy and genetic testing and the potential applications of molecular and cellular diagnostic strategies on the horizon.

  9. Deconstruction Geography: A STEM Approach

    Science.gov (United States)

    Gehlhar, Adam M.; Duffield, Stacy K.

    2015-01-01

    This article will define the engineering design process used to create an integrated curriculum at STEM Center Middle School, and it features the planning, implementation, and revision of the Deconstruction Geography unit. The Science Technology Engineering and Math (STEM) Center opened in the fall of 2009 as a way to relieve overcrowding at the…

  10. 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

    OpenAIRE

    Mumm, Rita H.; Goldsmith, Peter D.; Rausch, Kent D; Stein, Hans H

    2014-01-01

    Background 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 feedi...

  11. Photovoltaic energy conversion: Power from the sun. Technology, economic efficiency, market trends. 4. rev. and act. ed.; Photovoltaik - Strom aus der Sonne. Technologie, Wirtschaftlichkeit und Marktentwicklung

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, J. (ed.)

    1999-07-01

    The book reviews the physical and technical fundamentals of photovoltaic energy conversion, outlines the state of the art and presents examples, and goes into future prospects. [German] Mit Photovoltaik-Systemen laesst sich aus Solarenergie besonders umweltfreundlich und wartungsarm Elektrizitaet erzeugen. Diese Technologie traegt zur Schonung der fossilen Energievorraete und zum Abbau von Risiken in der Energieversorgung bei. In vielen Faellen ist sie nicht nur die komfortablere, sondern auch die wirtschaftlichere Loesung. Sie bietet besonders in den Laendern der Dritten Welt sehr guenstige, noch zu wenig genutzte Moeglichkeiten der Energieversorgung. Schwerpunkte heutiger Forschung sind die Erhoehung des Wirkungsgrades, die Zuverlaessigkeit der Komponenten und die Reduzierung der Kosten. Wirtschaftlichkeit ist jedoch eines von mehreren Kriterien bei der Wahl der optimalen Energieversorgung. Andere Vorzuege der Photovoltaik wie Geraeusch- und Emissionsfreiheit, Zuverlaessigkeit und Wartungsarmut koennen in vielen Faellen von groesserer Bedeutung sein als reine Kostenueberlegungen. Dieser Band fuehrt in die physikalischen und technischen Grundlagen ein, beschreibt, auch anhand von zahlreichen Beispielen, den Stand der Anwendungstechnik und zeigt Zukunftsperspektiven auf. (orig.)

  12. 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…

  13. European stem cell research in legal shackles

    NARCIS (Netherlands)

    Nielen, M.G.; de Vries, S.A.; Geijsen, N.

    2013-01-01

    Advances in stem cell biology have raised legal challenges to the patentability of stem cells and any derived technologies and processes. In 1999, Oliver Brustle was granted a patent for the generation and therapeutic use of neural cells derived from human embryonic stem cells (hESCs). The patent wa

  14. Understanding the STEM Pipeline. Working Paper 125

    Science.gov (United States)

    Sass, Tim R.

    2015-01-01

    I investigate the determinants of high school completion and college attendance, the likelihood of taking science, technology, engineering or math (STEM) courses in the first year of college and the probability of earning a degree in a STEM field. The focus is on women and minorities, who tend to be underrepresented in STEM fields. Tracking four…

  15. A State Policymaker's STEM Playbook. Promising Practices

    Science.gov (United States)

    Zinth, Jennifer; Goetz, Tami

    2016-01-01

    Science, technology, engineering and mathematics (STEM) has captured the attention of state policymakers who are concerned about equitable access to high-quality educational experiences and preparing and inspiring students to pursue STEM careers. Yet in many states, STEM policymaking efforts have not achieved their intended return on investment…

  16. New Technology of Drilling Fluids Conversion after Gas Drilling%气体钻井后气液转换新工艺

    Institute of Scientific and Technical Information of China (English)

    马庆涛

    2013-01-01

    In order to solve the problems such as formation hydration ,erosion ,borehole collapse ,loss of circulation ,which are likely to occur during drilling fluid conversion after gas drilling ,the gas-drilling fluid alteration process after gas drilling was studied .Three kinds of risks associated with conventional gas-drill-ing fluid conversion were analyzed .According to wettability reversal theory ,spraying wet reversal agent to borehole to make it oil-wet for keeping borehole stability .The procedure includes pulling the bit back up to the last casing ,then rotating bit ,spraying wet reversal agent to change the borehole wettability .Finally ,the drilling bit can be run to the bottom ,and pumping drilling fluids at low flow rate w hile tripping out at slow speed .The application of the procedure in Well Yuanye HF 1 in Yuanba Block showed ,the operation time was only 47% that of conversional method ,and the consumption of wet reversal agent was only 13% of that in conversional ways ,was no trouble occurred .It indicated that new alteration process for gas-drilling fluid was safe ,simple ,economic ,and effective ,could provide technical support for drilling fluid alteration after gas drilling in the future .%为了解决气体钻井后气液转换过程中容易出现的地层水化剥蚀、井壁坍塌、钻井液漏失等问题,对气体钻井后的气液转换工艺进行了研究。分析了3种常规气液转换工艺存在的风险,根据井壁润湿反转理论,在井壁上喷淋润湿反转剂使其形成亲油状态,保护井壁不坍塌;在注入钻井液前先将钻头提至上一层套管内,然后旋转钻头喷淋润湿反转剂,对井壁进行润湿反转处理;最后将钻头下到井底,边慢速起钻边小排量注入钻井液。在元坝区块元页H F 1井的应用表明,转换时间仅为常规气液转换工艺的47%,润湿反转剂消耗量仅为常规气液转换工艺的13%,整个过程无井下故障发生。这

  17. 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,…

  18. Fish stem cell cultures.

    Science.gov (United States)

    Hong, Ni; Li, Zhendong; Hong, Yunhan

    2011-04-13

    Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES) cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on "Fish Stem Cells and Nuclear Transfer", we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  19. Fish Stem Cell Cultures

    Directory of Open Access Journals (Sweden)

    Ni Hong, Zhendong Li, Yunhan Hong

    2011-01-01

    Full Text Available Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on “Fish Stem Cells and Nuclear Transfer”, we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  20. Technical and economic assessment of processes for the production of butanol and acetone. Phase two: analysis of research advances. Energy Conversion and Utilization Technologies Program

    Energy Technology Data Exchange (ETDEWEB)

    None

    1984-08-01

    The initial objective of this work was to develop a methodology for analyzing the impact of technological advances as a tool to help establish priorities for R and D options in the field of biocatalysis. As an example of a biocatalyzed process, butanol/acetone fermentation (ABE process) was selected as the specific topic of study. A base case model characterizing the technology and economics associated with the ABE process was developed in the previous first phase of study. The project objectives were broadened in this second phase of work to provide parametric estimates of the economic and energy impacts of a variety of research advances in the hydrolysis, fermentation and purification sections of the process. The research advances analyzed in this study were based on a comprehensive literature review. The six process options analyzed were: continuous ABE fermentaton; vacuum ABE fermentation; Baelene solvent extraction; HRI's Lignol process; improved prehydrolysis/dual enzyme hydrolysis; and improved microorganism tolerance to butanol toxicity. Of the six options analyzed, only improved microorganism tolerance to butanol toxicity had a significant positive effect on energy efficiency and economics. This particular process option reduced the base case production cost (including 10% DCF return) by 20% and energy consumption by 16%. Figures and tables.

  1. A Problem with STEM

    Science.gov (United States)

    Marder, Michael

    2013-01-01

    Striking differences between physics and biology have important implications for interdisciplinary science, technology, engineering, and mathematics (STEM) education. The author is a physicist with interdisciplinary connections. The research group in which he works, the Center for Nonlinear Dynamics at the University of Texas at Austin, is…

  2. STEM Sense and Nonsense

    Science.gov (United States)

    Charette, Robert N.

    2015-01-01

    If you can believe the daily flood of mass media stories, journal articles, and white papers, the United States is facing a STEM worker crisis. Business leaders and politicians warn that the nation is falling hopelessly behind in the global economic race because our students are unprepared for and uninterested in science, technology, engineering,…

  3. Application of Rotor Frequency Conversion Technology to Electric Control System of Mine Hoist%转子变频技术在矿井提升机电控系统中的应用

    Institute of Scientific and Technical Information of China (English)

    刘连君; 张传明; 李艳辉; 李军

    2011-01-01

    提升机TKD高压交流电控系统的节能变频改造一般选用高压变频方案,而矿井交流提升机普遍使用中小功率电机,高压变频的成本较高、性价比低,因此提出一种采用高压交流绕线电机转子变频调速控制系统的节能变频改造方案,将高压交流绕线电机的定子短封,使用低压变频器对电机的转子供电,实现高压交流绕线电机的变频调速控制。首先在山东新矿集团华恒公司副斜井提升机进行了工业运行试验,对电机性能进行测试分析,并统计了系统的节能效果,结果表明,电机的综合效率没有明显变化,功率因数提高到0.95,节电率效果显著。%The energy saving and frequency conversion reconstruction of the TKD high voltage AC electric control system for the mine hoist generally would adopt a high voltage frequency conversion alternative.In fact,the mine AC hoist would apply a medium or small power motor generally.The high voltage frequency conversion would have a high cost and a low performance and cost ratio.Therefore an energy saving and frequency conversion reconstruction alternative of the stator frequency conversion control system for the high voltage AC winding motor was provided.The stator would be short sealed for the high voltage AC winding motor.The low transformer would be applied to supply the power for the stator of the motor.Thus the frequency converted speed control could be realized for the high voltage AC winding motor.A industrial trial of the frequency conversion technology was first conducted on the hoist applied to the mine auxiliary inclined shaft of Huanheng Mine,Shandong Xinwen Coal Mining Group.The measurement and analysis were conducted on the performances of the electric motor and there was a statistic on the energy saving effect of the system.The results showed that the comprehensive efficiency of the electric motor had no obvious change,but the power factor was improved by 0.95 and the power

  4. The effects of science-technology-engineering-math (STEM integration on 5th grade students’ perceptions and attitudes towards these areasFen-teknoloji-mühendislik-matematik entegrasyonunun (STEM 5. sınıf öğrencilerinin bu alanlarla ilgili algı ve tutumlarına etkisi

    Directory of Open Access Journals (Sweden)

    Filiz Gülhan

    2016-01-01

    Full Text Available Science-Technology-Engineering-Math provide a basis to multiple disciplines. Nowadays STEM is a popular approach that consist of teaching Science-Technology-Engineering-Math in an interdisciplinary way. This research is conducted to study the effects of the integration of STEM on the attitude and perception of 5th grade students. In this research the quasi-experimental design with a pretest - posttest was conducted. The study group of the study in consist of 5th grade students who receive education in Istanbul. The control group consisted of 27 students and experimental group 28 students. In the research ‘STEM Perception Test’ and ‘STEM Attitude Test’ were used a quantitative data collecting device. For the ‘STEM Perception Test’ in the reliability analysis it was designated that the Cronbach Alpha worths of the test’s sub-dimensions changed between 0,703 and 0,892. For ‘STEM Attitude Test’ in the reliability analysis it was designated that the Cronbach Alpha worths of the test’s sub-dimensions changed between 0,786 and 0,900. In the control group the activities based on inquiry activities in the science books of Ministry of National Education were practiced and in the experimental group in addition to these activities the STEM activities developed by the researchers were practiced. In the research it was concluded that STEM activities developed the students’ perceptions and attitudes in these area. In the research it is regarded being development especially on engineering, technology, career areas in the perception test; and on science, engineering-technology areas in the attitude test. According to this results practicing of the STEM training was proposed to the teachers, researchers and the program makers.   Özet Günümüzde öne çıkan STEM eğitimi, birçok disipline temel oluşturan Fen-Teknoloji-Mühendislik-Matematik alanlarının disiplinlerarası yaklaşımla öğretilmesi fikrine dayanmaktadır. Bu ara

  5. Bioprinting for stem cell research.

    Science.gov (United States)

    Tasoglu, Savas; Demirci, Utkan

    2013-01-01

    Recently, there has been growing interest in applying 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 biomolecules 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 cells 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.

  6. Discussion of the Integration of Curriculum of Frequency Conversion Technology Teaching%变频技术一体化课程教学的探讨

    Institute of Scientific and Technical Information of China (English)

    范宝华

    2015-01-01

    Inverter technology is a basic course for automation specialty, is an emerging discipline, teaching has certain difficulty and learning. This article first analyzed the common problems in integrated curriculum "inverter technology", the significance and importance of the teaching of. Then expounds the specific reform measures on teaching materials, teachers, teaching content, teaching methods, teaching means and methods of assessment in the process of teaching. Practice has proved: using the new teaching method, integrated curriculum teaching new teaching methods is not only beneficial to the students' mastery of the theory of knowledge, but also for the students to improve industrial automation equipment, to adapt to the social development of industrial modernization, Shi Yingxin's assessment methods with non constant important role.%变频技术是自动化专业的基础课程,是一门不断发展的新兴学科,教与学都具有一定的难度。首先分析了变频技术一体化课程的重要性、意义和教学中存在的普遍问题。然后阐述了教学过程中对教材、教师、教学内容、教学方法、教学手段和考核方式的具体改革措施。实践证明,进行一体化课程教学采用新教学方法、新教学手段不仅有利于学生对理论知识的掌握,而且对于学生提高工业自动化设备认识,适应社会工业现代化发展、适应新的考核方式等有着非常重要的作用。

  7. 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

  8. 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

  9. Do conversations with virtual avatars increase feelings of social anxiety?

    Science.gov (United States)

    Powers, Mark B; Briceno, Nicole F; Gresham, Robert; Jouriles, Ernest N; Emmelkamp, Paul M G; Smits, Jasper A J

    2013-05-01

    Virtual reality (VR) technology provides a way to conduct exposure therapy with patients with social anxiety. However, the primary limitation of current technology is that the operator is limited to pre-programed avatars that cannot be controlled to interact/converse with the patient in real time. The current study piloted new technology allowing the operator to directly control the avatar (including speaking) during VR conversations. Using an incomplete repeated measures (VR vs. in vivo conversation) design and random starting order with rotation counterbalancing, participants (N = 26) provided ratings of fear and presence during both VR and in vivo conversations. Results showed that VR conversation successfully elevated fear ratings relative to baseline (d = 2.29). Participants also rated their fear higher during VR conversation than during in vivo conversation (d = 0.85). However, in vivo conversation was rated as more realistic than VR conversation (d = 0.74). No participants dropped out and 100% completed both VR and in vivo conversations. Qualitative participant comments suggested that the VR conversations would be more realistic if they did not meet the actor/operator and if they were not in the same room as the participant. Overall, the data suggest that the novel technology allowing real time interaction/conversation in VR may prove useful for the treatment of social anxiety in future studies.

  10. Conversion chimique du gaz naturel Chemical Conversion of Natural Gas

    Directory of Open Access Journals (Sweden)

    Chaumette P.

    2006-11-01

    Full Text Available Dans cet article sont passés en revue les travaux de recherche et développement et les procédés existants dans le domaine de la conversion chimique du gaz naturel. Les deux voies possibles, conversion directe du méthane et conversion indirecte, via le gaz de synthèse, sont présentées. Tant la préparation d'hydrocarbures utilisables comme carburants, que celle des composés de bases pour la pétrochimie ou la chimie sont évoquées. L'accent est mis sur l'étape clé du développement de chaque procédé qui, selon le produit visé, consiste en la mise au point d'un nouveau système catalytique, en un changement de la technologie du réacteur, ou en la mise au point d'une section fractionnement moins complexe. This article reviews the research and development work and the existing processes in the area of chemical conversion of natural gas. The two possible methods, direct conversion of methane and indirect conversion via synthesis gas, are discussed. The preparation of hydrocarbons that can be used as fuels and the production of building blocks for the petrochemical and chemical industries are both dealt with. The accent is placed on the key step in developing each process. Depending on the target product, this key step consists in working out a new catalytic system, changing reactor technology or engineering a less complex fractionation section.

  11. Stem Cells

    Directory of Open Access Journals (Sweden)

    Madhukar Thakur

    2015-02-01

    Full Text Available Objective: The objective of this presentation is to create awareness of stem cell applications in the ISORBE community and to foster a strategy of how the ISORBE community can disseminate information and promote the use of radiolabeled stem cells in biomedical applications. Methods: The continued excitement in Stem Cells, in many branches of basic and applied biomedical science, stems from the remarkable ability of stem cells to divide and develop into different types of cells in the body. Often called as Magic Seeds, stem cells are produced in bone marrow and circulate in blood, albeit at a relatively low concentration. These virtues together with the ability of stem cells to grow in tissue culture have paved the way for their applications to generate new and healthy tissues and to replace diseased or injured human organs. Although possibilities of stem cell applications are many, much remains yet to be understood of these remarkable magic seeds. Conclusion: This presentation shall briefly cover the origin of stem cells, the pros and cons of their growth and division, their potential application, and shall outline some examples of the contributions of radiolabeled stem cells, in this rapidly growing branch of biomedical science

  12. Analysis of the Two Conversion Technology of I/O Interface Control Computer%计算机I/O接口控制二次转换技术分析

    Institute of Scientific and Technical Information of China (English)

    陈显; 蒋明礼

    2015-01-01

    The computer technology is the products of information technology era,with the powerful data processing function, and can meet the different needs of the user data manipulation.The I /O interface is the core part of a computer system,and can be used as the data transmission and control,realize the control integration of data resources.Taking into account the user data processing requirements are more and more high,we must carry on the optimization of I /O interface function,strengthen the overall efficiency of the original data structure operation.This paper analyzes the existing problems of computer I /O inter-face application,summed up the two characteristics of conversion technology,and I /O interface conversion of two proposed sci-entific measures.%计算机技术是信息化时代产物,具备强大的数据处理功能特点,满足了不同用户操控数据的使用需求。I /O 接口是计算机系统的核心部分,可用作各类数据传输与操控处理,实现了数据资源的一体化控制。考虑到用户数据操作处理要求越来越高,必须要对 I /O 接口功能进行优化改造,强化原始数据结构运行的总体效率。本文分析了计算机 I /O 接口应用存在的问题,总结二次转换技术使用特点,对 I /O 接口二次转换处理提出科学的措施。

  13. Chinese Conversation Structure

    Institute of Scientific and Technical Information of China (English)

    LIU Yan

    2016-01-01

    This paper aims to describe the features of Chinese conversation structure. Specifically speaking, the structure will be analyzed from the following four aspects:openings and pre-sequence, adjacency pairs, pre-closing and closing. Generally speak-ing, Chinese conversation structure is similar to English conversation structure. But still a lot of differences are found due to cul-tural factors.

  14. Cost-effectiveness analysis comparing continuation of assisted reproductive technology with conversion to intrauterine insemination in patients with low follicle numbers.

    Science.gov (United States)

    Yu, Bo; Mumford, Sunni; Royster, G Donald; Segars, James; Armstrong, Alicia Y

    2014-08-01

    To compare the cost effectiveness of proceeding with oocyte retrieval vs. converting to intrauterine insemination (IUI) in patients with ≤4 mature follicles during assisted reproductive technology (ART) cycles. Probabilistic decision analysis. The cost effectiveness of completing ART cycles in poor responders was compared to that for converting the cycles to IUI. Not applicable. Not applicable. Cost-effectiveness analysis. Cost effectiveness, which was defined as the average direct medical costs per ongoing pregnancy. In patients with 1-3 mature follicles, completing ART was more cost effective if the cost of a single ART cycle was between $10,000 and $25,000. For patients with 4 mature follicles, if an ART cycle costcost effective to continue with oocyte retrieval than to convert to IUI. In patients with ≤4 mature follicles following ovarian stimulation in ART cycles, it was on average more cost effective to proceed with oocyte retrieval rather than convert to IUI. However, important factors, such as age, prior ART failures, other fertility factors, and medications used in each individual case need to be considered before this analysis model can be adapted by individual practices. Copyright © 2014 American Society for Reproductive Medicine. All rights reserved.

  15. 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.

  16. Inclusive STEM High School Design: 10 Critical Components

    Science.gov (United States)

    Peters-Burton, Erin E.; Lynch, Sharon J.; Behrend, Tara S.; Means, Barbara B.

    2014-01-01

    Historically, the mission of science, technology, engineering, and mathematics (STEM) schools emphasized providing gifted and talented students with advanced STEM coursework. However, a newer type of STEM school is emerging in the United States: inclusive STEM high schools (ISHSs). ISHSs have open enrollment and are focused on preparing…

  17. 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

  18. Biomass Conversion into Solid Composite Fuel for Bed-Combustion

    Directory of Open Access Journals (Sweden)

    Tabakaev Roman B.

    2015-01-01

    Full Text Available The purpose of this research is the conversion of different types of biomass into solid composite fuel. The subject of research is the heat conversion of biomass into solid composite fuel. The research object is the biomass of the Tomsk region (Russia: peat, waste wood, lake sapropel. Physical experiment of biomass conversion is used as method of research. The new experimental unit for thermal conversion of biomass into carbon residue, fuel gas and pyrolysis condensate is described. As a result of research such parameters are obtained: thermotechnical biomass characteristics, material balances and product characteristics of the heat-technology conversion. Different methods of obtaining solid composite fuel from the products of thermal technologies are considered. As a result, it is established: heat-technology provides efficient conversion of the wood chips and peat; conversion of the lake sapropel is inefficient since the solid composite fuel has the high ash content and net calorific value.

  19. iSTEM: Learning Mathematics through Minecraft

    Science.gov (United States)

    Bos, Beth; Wilder, Lucy; Cook, Marcelina; O'Donnell, Ryan

    2014-01-01

    The Common Core State Standards can be taught with Minecraft, an interactive creative Lego®-like game. Integrating Science, Technology, Engineering, and Mathematics (iSTEM) authors share ideas and activities that stimulate student interest in the integrated fields of science, technology, engineering, and mathematics (STEM) in K-grade 6 classrooms.

  20. 永磁风力发电系统及其功率变换技术%Wind Energy Conversion System Based on PMSG and Its Power Converter Technology

    Institute of Scientific and Technical Information of China (English)

    夏长亮

    2012-01-01

    As a kind of efficient and clean renewable energy, wind energy receives much concern. Wind energy conversion system (WECS) based on permanent magnet synchronous generator (PMSG) has become one of the most significant development directions of wind energy technologies because of its outstanding comprehensive superiority. This paper discusses the structures, driven types and operation characteristics of PMSGs in WECSs. Then the topologies, controls and applications of the power converters suitable for WECSs based on PMSG are illustrated. The development trend of WECS based on PMSG technologies are analyzed finally. With rapid development of wind energy and its related technologies, the WESCs based on PMSGs will have broad prospects.%风能作为一种高效清洁的可再生能源备受关注。作为风力发电领域中主要机型之一,永磁风力发电系统的综合优势较为突出,使其成为风力发电技术发展的重要方向之一。本文重点论述了永磁风力发电系统中永磁同步发电机的结构特点、驱动形式以及运行特性;阐述了永磁风力发电系统中功率变换器的拓扑结构、控制特点及适用场合;分析了永磁风力发电技术的发展趋势。随着风电技术及相关领域技术的飞速发展,永磁风力发电技术将具有广阔的发展前景。

  1. 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

  2. NGL data conversion system

    Science.gov (United States)

    Shoji, Masahiro; Horiuchi, Nobuyasu

    2005-06-01

    We are developing a NGL data conversion system for EPL, for LEEPL, and for EBDW, which is based on our established photomask data conversion system, PATACON PC-cluster. For EPL data conversion, it has SF division, Complementary division, Stitching, Proximity effect correction, Alignment mark insertion, EB stepper control data creation, and Mask inspection data creation. For LEEPL data conversion, it has Pattern checking, Complementary division, Stitching, Stress distortion correction, Alignment mark insertion, and Mask inspection data creation. For EB direct-writing data conversion, it has Proximity effect correction and Extraction of aperture pattern for cell projection exposure.

  3. STEM on the radio

    Science.gov (United States)

    Showstack, Randy

    2011-10-01

    Looking for an Internet radio station focusing on programing about science, technology, engineering, and math (STEM)? The U.S. National Science Foundation (NSF) announced on 26 September the launch of Science360 Radio, which it says is the first Internet radio stream dedicated to STEM programing. Science360 includes more than 100 radio shows and podcasts that are available on the Web as well as on iPhone and Android devices. The shows originate from a variety of sources, including NSF, other U.S. government agencies, science organizations, universities, and media outlets. For more information, see http://science360.gov/files/.

  4. Research of Low-Voltage Frequency Conversion Shore Connection Technology in Qinhuangdao Port%秦皇岛港低压变频岸电技术方案研究

    Institute of Scientific and Technical Information of China (English)

    李婷

    2012-01-01

    为进一步实现港口节能减排,秦皇岛港提出低压变频岸电技术方案。分析国内外港口采用的岸电技术与发展趋势,结合秦皇岛港煤五期码头到港主力船型、码头供电设施等情况,进行低压变频岸电方案研究。提出切实可行的岸电设计方案,并分析优缺点,为该港岸电最终方案择选提供可靠的方案支撑。可持续发展是秦皇岛港中远期提升煤炭运输市场竞争力的需要。%In order to realize further power-saving and exhaustion-reducing of Port, a technical plan of low-voltage frequency conversion is put forward by Qinhuangdao Port. The technology and development trend of shore connection in domestic and foreign ports is analyzed. Low-voltage frequency conversion shore connection project is researched , combined with the main ship type in port and connection supply facilities of the wharf in QHD port. The practical and feasible shore connection scheme is proposed, and the advantages and disadvantages of the scheme is analyzed for providing reliable solutions to support to the final choice. The project is the need of raising coal transport market competitiveness in long-term for Qinhuangdao Port.

  5. 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.

  6. 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.

  7. 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

  8. SPS Energy Conversion Power Management Workshop

    Science.gov (United States)

    1980-01-01

    Energy technology concerning photovoltaic conversion, solar thermal conversion systems, and electrical power distribution processing is discussed. The manufacturing processes involving solar cells and solar array production are summarized. Resource issues concerning gallium arsenides and silicon alternatives are reported. Collector structures for solar construction are described and estimates in their service life, failure rates, and capabilities are presented. Theories of advanced thermal power cycles are summarized. Power distribution system configurations and processing components are presented.

  9. Pluripotent stem cell-derived neural stem cells: From basic research to applications

    Institute of Scientific and Technical Information of China (English)

    Masahiro; Otsu; Takashi; Nakayama; Nobuo; Inoue

    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 in vitro techniques to manipulate stem cells. This review summarizes the techniques required to generate neural cells from pluripotent stem cells. In particular, this review describes current research applications of a simple neural differentiation method, the neural stem sphere method, which we developed.

  10. Energy conversion & storage program. 1994 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Cairns, E.J.

    1995-04-01

    The Energy Conversion and Storage Program investigates state-of-the-art electrochemistry, chemistry, and materials science technologies for: (1) development of high-performance rechargeable batteries and fuel cells; (2) development of high-efficiency thermochemical processes for energy conversion; (3) characterization of complex chemical processes and chemical species; (4) study and application of novel materials for energy conversion and transmission. Research projects focus on transport process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis.

  11. Stem Cells

    DEFF Research Database (Denmark)

    Sommerlund, Julie

    2004-01-01

    '. 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...... and tantalizing than stem cells, in research, in medicine, or as products....

  12. Uranium conversion; Conversion de l`uranium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-01

    This booklet is a presentation of the activities of the Comurhex company, created in 1971 and which became a 100% Cogema`s daughter company in 1992. The Comurhex company is in charge of the conversion of natural uranium into gaseous uranium hexafluoride (UF{sub 6}). The two steps of the conversion operation are performed in the Malvesi and Pierrelatte (France) industrial sites and represent 31% (14000 t/year) of the uranium conversion capacity of western countries. The refining and UF{sub 4} production (Malvesi) and the UF{sub 6} fabrication (Pierrelatte) processes are described. Comurhex is also one of the few companies in the world which produces UF{sub 6} from the uranium of spent fuels. (J.S.)

  13. 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.

  14. 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

  15. 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...

  16. Development and application of stem cells

    Institute of Scientific and Technical Information of China (English)

    HUI Guo-zhen; SHAN Li-dong

    2005-01-01

    @@ Stem cells are defined by two important characteristics: the ability to proliferate by a process of self-renewal and the potential to form at least one specialized cell type. Transient population of pluripotent or multipotent stem cells first appear during the development at the first days post coitum. The cells of the inner cell mass (ICM) of the blastocyst, of which embryonic stem cells (ES) are the in vitro counterpart, can give rise to any differentiated cell type in the three primary germ layers of the embryo (endoderm, mesoderm and ectoderm).1-3 These cells gradually mature into committed, organ- and tissue-specific stem cells or adult stem cells, such as neural stem cells, mesenchymal stem cells, hematopoietic stem cells, etc. Over the past years, studies have focused on two aspects: molecular level and application, and some new methods and technology have been used.

  17. Ethics and Governance of Stem Cell Banks.

    Science.gov (United States)

    Chalmers, Donald; Rathjen, Peter; Rathjen, Joy; Nicol, Dianne

    2017-01-01

    This chapter examines the ethical principles and governance frameworks for stem cell banks. Good governance of stem cell banks should balance facilitation of the clinical use of stem cells with the proper respect and protection of stem cell sample providers and stem cell recipients and ensure compliance with national regulatory requirements to foster public trust in the use of stem cell technology. Stem cell banks must develop with regard to the science, the needs of scientists, and the requirements of the public, which will benefit from this science. Given the international reach of this promising research and its clinical application, it is necessary for stem cell bank governance frameworks to be harmonized across jurisdictions.

  18. 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 ...

  19. 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

  20. Emerging molecular approaches in stem cell biology.

    Science.gov (United States)

    Jaishankar, Amritha; Vrana, Kent

    2009-04-01

    Stem cells are characterized by their ability to self-renew and differentiate into multiple adult cell types. Although substantial progress has been made over the last decade in understanding stem cell biology, recent technological advances in molecular and systems biology may hold the key to unraveling the mystery behind stem cell self-renewal and plasticity. The most notable of these advances is the ability to generate induced pluripotent cells from somatic cells. In this review, we discuss our current understanding of molecular similarities and differences among various stem cell types. Moreover, we survey the current state of systems biology and forecast future needs and direction in the stem cell field.

  1. Optimization of three-dimensional imaging on in vitro produced porcine blastocysts and chimeras for stem cell testing: A technology report

    DEFF Research Database (Denmark)

    Secher, Jan; Freude, Karla; Li, Rong

    2015-01-01

    Differential staining is an immunocytochemical staining that visualizes trophectoderm (TE) and the inner cell mass (ICM) of the blastocysts. It is used to determine the blastocyst quality, but could also be a useful tool to assess the integration site of injected cells into the early embryo....... This is relevant for testing of presumed pluripotent stem cells. The gold standard for pluripotent stem cells is to test if the cells are capable of contributing to germline chimeras. Differential staining can be used to evaluate the possibility of chimeric contribution; if the cells are located in the area...... of the ICM they are likely to contribute to the fetus and if they are located in the area of the TE they are likely to contribute to the fetal membranes. In this article, we optimize on methods for embryo staining and mounting so that the exact location of injected stem cells within preimplantation porcine...

  2. Perceptions, Engagement, and Practices of Teachers Seeking Professional Development in Place-Based Integrated STEM

    Science.gov (United States)

    Nadelson, Louis S.; Seifert, Anne

    2013-01-01

    As science, technology, engineering, and mathematics (STEM) continue to grow in economic and social importance, it is critical that citizenry are prepared to be STEM literate. Furthermore, the workforce demands on STEM necessitate students seeking STEM degrees and pursuing STEM careers. Primary and secondary (K-12) teachers play an important role…

  3. 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

    We have generated a human induced pluripotent stem cell (iPSC) line derived from urinary cells of 1 28-30 year old healthy female donor. The cells were reprogrammed using a non-integrating viral vector and shown to have full differentiation potential. Together with the iPSC-lines, the donors provided blood cells for the study of immunological effects of the iPSC line and its derivatives in autologous and allogeneic settings. The line is available and registered in the human pluripotent stem cell registry as BCRTi004-A.

  4. Observe-reflect-act: The cycle of reflective practice on questioning in STEM education

    Science.gov (United States)

    Ginley, Erica

    Countless studies have been conducted on questioning techniques in education. However, little research has been focused on the use of reflective practice in relation to teachers' questioning techniques in STEM: Science, Technology, Engineering and Math education. Within this action research study of my own teaching, six lessons were taught, observed, and reflected upon. The main focus was on whether and how reflective practice influences questioning. Through the analysis of video footage, conversation transcriptions, reflective journal entries, pre-service teacher survey, and student work, the importance of different questioning techniques became apparent. They demonstrated that reflective practice has an impact on improving questioning skills and, thus, better engaging students in the learning process.

  5. 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…

  6. 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…

  7. 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.

  8. Wavelength conversion based spectral imaging

    DEFF Research Database (Denmark)

    Dam, Jeppe Seidelin

    There has been a strong, application driven development of Si-based cameras and spectrometers for imaging and spectral analysis of light in the visible and near infrared spectral range. This has resulted in very efficient devices, with high quantum efficiency, good signal to noise ratio and high...... resolution for this spectral region. Today, an increasing number of applications exists outside the spectral region covered by Si-based devices, e.g. within cleantech, medical or food imaging. We present a technology based on wavelength conversion which will extend the spectral coverage of state of the art...... visible or near infrared cameras and spectrometers to include other spectral regions of interest....

  9. A Nuanced Look at Women in STEM Fields at Two-Year Colleges: Factors That Shape Female Students' Transfer Intent

    Science.gov (United States)

    Wang, Xueli; Chan, Hsun-yu; Soffa, Sara Jimenez; Nachman, Brett Ranon

    2017-01-01

    In this study, we explored the relationship between the intent to transfer upward and a set of motivational, contextual, and socio-demographic background factors among 696 female students beginning in science, technology, engineering, and mathematics (STEM) programs or courses at two-year colleges in a Midwestern state. Drawing upon survey data and administrative records, our multinomial logistic regression analysis revealed that students' math and science self-efficacy beliefs, as well as transfer-oriented interaction, were significant and positive predictors for their intent to transfer into STEM fields as opposed to having no intent to transfer. In addition, the association between transfer intent and these key motivational and contextual factors was moderated by students' racial/ethnic backgrounds, marital status, and childcare obligations. For example, despite the positive relationship between transfer-oriented interaction and the intention to transfer into STEM fields, Black women were less likely to have intent to transfer into STEM fields than White students until Black students reported a moderate level of transfer-oriented interaction. Conversely, Hispanic students were more likely to report intent to transfer into STEM fields than their White peers, even when Hispanic students reported a relatively low level of engagement in transfer-oriented interaction. These and other reported findings bear important and nuanced implications as policymakers, educators, and researchers continue to discover ways to better support women's educational pathways and success in STEM fields at and through two-year colleges. PMID:28220102

  10. A Nuanced Look at Women in STEM Fields at Two-Year Colleges: Factors That Shape Female Students' Transfer Intent.

    Science.gov (United States)

    Wang, Xueli; Chan, Hsun-Yu; Soffa, Sara Jimenez; Nachman, Brett Ranon

    2017-01-01

    In this study, we explored the relationship between the intent to transfer upward and a set of motivational, contextual, and socio-demographic background factors among 696 female students beginning in science, technology, engineering, and mathematics (STEM) programs or courses at two-year colleges in a Midwestern state. Drawing upon survey data and administrative records, our multinomial logistic regression analysis revealed that students' math and science self-efficacy beliefs, as well as transfer-oriented interaction, were significant and positive predictors for their intent to transfer into STEM fields as opposed to having no intent to transfer. In addition, the association between transfer intent and these key motivational and contextual factors was moderated by students' racial/ethnic backgrounds, marital status, and childcare obligations. For example, despite the positive relationship between transfer-oriented interaction and the intention to transfer into STEM fields, Black women were less likely to have intent to transfer into STEM fields than White students until Black students reported a moderate level of transfer-oriented interaction. Conversely, Hispanic students were more likely to report intent to transfer into STEM fields than their White peers, even when Hispanic students reported a relatively low level of engagement in transfer-oriented interaction. These and other reported findings bear important and nuanced implications as policymakers, educators, and researchers continue to discover ways to better support women's educational pathways and success in STEM fields at and through two-year colleges.

  11. Journal of STEM Education

    OpenAIRE

    Ernst, Jeremy V.; Clark, Aaron C.

    2012-01-01

    Beginning in 2009, the North Carolina Virtual Public Schools worked with researchers at the William and Ida Friday Institute to produce and evaluate the use of game creation by secondary students as a form of learning content related to career awareness in Science, Technology, Engineering, and Mathematics (STEM) disciplines, with particular emphasis in computer science areas. The study required the development of different forms of multimedia, inclusive with content and activities that could ...

  12. The Conversation Class

    Science.gov (United States)

    Jackson, Acy L.

    2012-01-01

    The conversation class occupies a unique place in the process of learning English as a second or foreign language. From the author's own experience in conducting special conversation classes with Persian-speaking adults, he has drawn up a number of simple but important guidelines, some of which he hopes may provide helpful suggestions for the…

  13. Content for Conversation Partners.

    Science.gov (United States)

    Olson, Kathleen

    2002-01-01

    Suggests that a good strategy for helping English language learners to develop communicative competence in English is by pairing them with native English speakers. In such conversation programs, conversation partners should be provided with topics and activities that incorporate the goals, interests, and experiences of the learners. Recommends…

  14. Canning Canned Conversations.

    Science.gov (United States)

    Gilmore, Michael P.; Daigaku, Sanyo

    Ways to improve the role-playing conversations found in most second language textbooks are outlined. It is argued that the conversations are often restrictive, dull, and repetitive, and students respond to them in kind. The teacher can make the target language used more interesting by creating new characters, situations, settings, or objectives.…

  15. Hydrothermal conversion of biomass

    NARCIS (Netherlands)

    Knezevic, Dragan

    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 wat

  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. The changes of cardioelectrical activity of rat with myocardial infarction receiving sarcoplasmic reticulum Ca2+-ATPase gene modified bone marrow stem cell transplantation by microelectrode array technology

    Institute of Scientific and Technical Information of China (English)

    范平

    2012-01-01

    Objective Therapy effects and cardiac electrical activity comparison of bone marrow stem cells (BMSCs) transplantation and sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) gene modified BMSCs transplantation after acute myocardial infarction(AMI) in rats.Methods Rats with AMI were divided

  18. Gender Differences in Science, Technology, Engineering, and Mathematics (STEM) Interest, Credits Earned, and NAEP Performance in the 12th Grade. Stats in Brief. NCES 2015-075

    Science.gov (United States)

    Cunningham, Brittany C.; Hoyer, Kathleen Mulvaney; Sparks, Dinah

    2015-01-01

    As technical and scientific innovation continue to drive the global economy, educators, policymakers, and scientists seek to promote students' interest and achievement in the STEM fields to maintain the nation's competitive position (National Academy of Sciences 2006; National Science Board 2007; President's Council of Advisors on Science and…

  19. Stem cell mitochondria during aging.

    Science.gov (United States)

    Min-Wen, Jason Chua; Jun-Hao, Elwin Tan; Shyh-Chang, Ng

    2016-04-01

    Mitochondria are the central hubs of cellular metabolism, equipped with their own mitochondrial DNA (mtDNA) blueprints to direct part of the programming of mitochondrial oxidative metabolism and thus reactive oxygen species (ROS) levels. In stem cells, many stem cell factors governing the intricate balance between self-renewal and differentiation have been found to directly regulate mitochondrial processes to control stem cell behaviors during tissue regeneration and aging. Moreover, numerous nutrient-sensitive signaling pathways controlling organismal longevity in an evolutionarily conserved fashion also influence stem cell-mediated tissue homeostasis during aging via regulation of stem cell mitochondria. At the genomic level, it has been demonstrated that heritable mtDNA mutations and variants affect mammalian stem cell homeostasis and influence the risk for human degenerative diseases during aging. Because such a multitude of stem cell factors and signaling pathways ultimately converge on the mitochondria as the primary mechanism to modulate cellular and organismal longevity, it would be most efficacious to develop technologies to therapeutically target and direct mitochondrial repair in stem cells, as a unified strategy to combat aging-related degenerative diseases in the future.

  20. Geothermal Power Technologies

    DEFF Research Database (Denmark)

    Montagud, Maria E. Mondejar; Chamorro, C.R.

    2016-01-01

    Although geothermal energy has been widely deployed for direct use in locations with especial geologic manifestations, its potential for power generation has been traditionally underestimated. Recent technology developments in drilling techniques and power conversion technologies from low...

  1. 基于PLC的微灌变频控制系统的设计与应用%Design and Application of Frequency Conversion Control System for Micro-irrigation Based on PLC Technology

    Institute of Scientific and Technical Information of China (English)

    李浩; 李金山; 段福义; 韩启彪; 孙秀路; 孙浩; 陈震

    2015-01-01

    Now in China ,the automation technology for water-saving irrigation in field is relatively backward .A PLC micro-irrigation frequency conversion control system is designed to save water and energy ,and give the flexible irrigation schemes ,as well as to give friendly man-machine interface for easy to operation .This control system ,by means of motor frequency conversion ,adjusts the wa‐ter pump to make sure that the micro-irrigation system runs steadily under set pressure .The touch screen's real-time display ,moni‐tor and control of the various working parameters make the choice of irrigation plans flexible .Field tests show that this system has favorable interface ,this system can face the needs of the micro-irrigation system under different pressures ,and this system has flexi‐ble irrigation plans ,so this system can save water .Compared with the traditional constant pressure irrigation ,this system saves en‐ergy for the frequency conversion control of the motor .%我国田间节水灌溉自动化技术相对落后,为增加节水节能效率,针对农业灌溉过程中,灌溉系统、灌溉方案的选择缺乏灵活性,缺乏友好的人机交互界面,操作复杂等情况,研究并设计了基于PLC技术的微灌变频控制系统。该控制系统通过电动机变频调速的方法,调节水泵运行工况,从而保证微灌系统在设定压力下稳定运行,并通过触摸屏实时显示、监测和控制系统运行的各工况参数,提高了作物灌溉方案选择的灵活性。田间试验表明,该系统人机界面良好,能够较好地满足微灌系统不同压力的需要,并可以灵活设定和选择灌溉方案,达到节水灌溉的目的。同时由于电机的变频控制具有较好的节能作用,与传统恒压灌溉的方式比,进一步降低了能源的浪费。

  2. 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

  3. 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.

  4. 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...

  5. Research and Design on Monolithic Integrated R/D Conversion and Digital P rocessing Technology%单片集成R/D转换及数字处理技术研究与设计

    Institute of Scientific and Technical Information of China (English)

    陈大科

    2015-01-01

    This paper introduces the design method of R/D conversion technology and products. A novel Implementation of the digital R/D converter combining digital signal processing technology with sigma⁃delta (Σ-Δ) ADC is established. The typical structure of Σ-Δ ADC is optimized to fit for the requirement of real⁃time data processing. The digital phase sensitive detection is acquired by calculating the cross correlation function of internal synthetic reference sequence and digital signal sequence of Σ-Δ modulator. To realize fast conversion, the digital processing and filtering circuit in ADC are integrated into the type 2 tracking closed⁃loop system. This method can simplify circuit structure and reduce chip size. The RTL code of dig⁃ital integrator and filter are designed in Verilog language. The proposed design is verified by mixed⁃signal simulation. The co⁃simulation method based on MATLAB/Simulink and Cadence is used to analysis convertor output spectrum. Finally, a practi⁃cal circuit for R/D converter is described. The experiments results show that the presented method is effective and the per⁃formances of the R/D convertor come up to the level of the same products from abroad.%介绍了R/D转换技术及单芯片产品的设计方法。探讨采用数字信号处理技术和Σ-ΔADC(模数转换器)实现数字R/D转换的方法。为满足系统的实时数据处理要求,对典型的Σ-ΔADC结构进行了改进,将Σ-Δ调制器得到信号的数字序列,通过内部合成正弦波序列和信号序列的互相关函数实现数字相敏检测。将ADC中的数字处理及滤波电路融合到R/D解算的2型闭环系统中,实现快速转换,简化了电路设计并有效降低芯片面积。数字积分及滤波器采用Verilog语言编写的RTL级代码,采用数模混合仿真实现R/D的整体电路验证。通过Matlab与cadence软件协同仿真方法对转换数据进行频谱特性分析。最后,给

  6. 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.

  7. Analysis of Evaluation Technology of Insulation Systems for High Voltage Frequency Conversion Motor%高压变频电机绝缘结构评价技术解析

    Institute of Scientific and Technical Information of China (English)

    黄慧洁

    2014-01-01

    Evaluation technology of the insulation systems for high voltage frequency conversion motor was introduced, including thermal evaluation, acceptance test for mainwall insulation systems, and qualification tests for mainwall insulation systems, turn insulation systems, and stress control systems. It analyzed the difficulties met in electrical evaluation of the insulation systems, such as the unknown machine terminal voltages waveshape arising from converter operation, no reference systems can be used in mainwall insulation systems qualification tests, no test equipments to simulate the actual running situation of insulation systems. Methods to solve these problems were also discussed for reference.%介绍了高压变频电机绝缘结构评价技术,包括热评价、主绝缘认可试验及对主绝缘、匝间绝缘、应力控制和防晕结构的鉴别试验。讨论了目前高压变频电机绝缘结构电评价过程中遇到的电机运行时可能出现的端电压波形未知、主绝缘鉴别试验无基准结构可参考、难以获得完全模拟实际情况的电源条件等问题,并分析了解决这些问题的对策,供高压变频电机制造商和用户参考。

  8. 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.

  9. 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

  10. 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...... of design. Three distinctions are drawn through which to develop this discussion of models in an architectural context. An examination of these distinctions serves to nuance particular characteristics and roles of models, the modelling activity itself and those engaged in it....

  11. 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

  12. 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.

  13. Energy Conversion in Protocells with Natural Nanoconductors

    Directory of Open Access Journals (Sweden)

    Jian Xu

    2012-01-01

    Full Text Available While much nanotechnology leverages solid-state devices, here we present the analysis of designs for hybrid organic-inorganic biomimetic devices, “protocells,” based on assemblies of natural ion channels and ion pumps, “nanoconductors,” incorporated into synthetic supported lipid bilayer membranes. These protocells mimic the energy conversion scheme of natural cells and are able to directly output electricity. The electrogenic mechanisms have been analyzed and designs were optimized using numerical models. The parameters that affect the energy conversion are quantified, and limits for device performance have been found using numerical optimization. The electrogenic performance is compared to conventional and emerging technologies and plotted on Ragone charts to allow direct comparisons. The protocell technologies summarized here may be of use for energy conversion where large-scale ion concentration gradients are available (such as the intersection of fresh and salt water sources or small-scale devices where low power density would be acceptable.

  14. 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.

  15. 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 semiconductor s

  16. Structured luminescence conversion layer

    Science.gov (United States)

    Berben, Dirk; Antoniadis, Homer; Jermann, Frank; Krummacher, Benjamin Claus; Von Malm, Norwin; Zachau, Martin

    2012-12-11

    An apparatus device such as a light source is disclosed which has an OLED device and a structured luminescence conversion layer deposited on the substrate or transparent electrode of said OLED device and on the exterior of said OLED device. The structured luminescence conversion layer contains regions such as color-changing and non-color-changing regions with particular shapes arranged in a particular pattern.

  17. Managing social media conversations

    OpenAIRE

    2015-01-01

    The purpose of this thesis was to explore how companies can manage (monitor and control) social media conversations. Regardless of the companies’ presence in social media networks, they or their industry are constantly being discussed in social media. Therefore organisations should be present in social media, monitor and participate in conversations, in order to turn them into their benefit. There are software and services available to help in monitoring. Variety of tools and statistic de...

  18. Will brain cells derived from induced pluripotent stem cells or directly converted from somatic cells (iNs) be useful for schizophrenia research?

    Science.gov (United States)

    Filippich, Cheryl; Wolvetang, Ernst J; Mowry, Bryan J

    2013-09-01

    The reprogramming of nonneuronal somatic cells to induced pluripotent stem cells and their derivation to functional brain cells as well as the related methods for direct conversion of somatic cells to neurons have opened up the possibility of conducting research on cellular disease models from living schizophrenia patients. We review the published literature on schizophrenia that has used this rapidly developing technology, highlighting the need for specific aims and reproducibility. The key issues for consideration for future schizophrenia research in this field are discussed and potential investigations using this technology are put forward for critical assessment by the reader.

  19. 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…

  20. 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…