WorldWideScience

Sample records for nonroad engine growth

  1. 40 CFR 89.609 - Final admission of modification nonroad engines and test nonroad engines.

    Science.gov (United States)

    2010-07-01

    ... has not been placed on a currently effective EPA list of ICIs ineligible to import such modification... submittal of the ICI's application under paragraph (b) of this section. (e) EPA list of ICIs ineligible to import nonroad engines for modification/test. EPA maintains a current list of ICIs who have...

  2. 77 FR 9916 - California State Motor Vehicle and Nonroad Engine Pollution Control Standards; Mobile Cargo...

    Science.gov (United States)

    2012-02-21

    ... AGENCY California State Motor Vehicle and Nonroad Engine Pollution Control Standards; Mobile Cargo... to the control of emissions from new motor vehicles or new motor vehicle engines ] EPA is, pursuant... standards relating to the control of emissions for new motor vehicles and new motor vehicle engines...

  3. 40 CFR Appendix A to Subpart A of... - State Regulation of Nonroad Internal Combustion Engines

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false State Regulation of Nonroad Internal Combustion Engines A Appendix A to Subpart A of Part 89 Protection of Environment ENVIRONMENTAL PROTECTION...-IGNITION ENGINES General Pt. 89, Subpt. A, App. A Appendix A to Subpart A of Part 89—State Regulation...

  4. 77 FR 9239 - California State Motor Vehicle and Nonroad Engine Pollution Control Standards; Truck Idling...

    Science.gov (United States)

    2012-02-16

    ... AGENCY California State Motor Vehicle and Nonroad Engine Pollution Control Standards; Truck Idling... relating to the control of emissions from new motor vehicles or new motor vehicle engines subject to this... standards (other than crankcase emission standards) for the control of emissions from new motor vehicles or...

  5. 75 FR 43975 - California State Motor Vehicle and Nonroad Engine Pollution Control Standards; Truck Idling...

    Science.gov (United States)

    2010-07-27

    ... AGENCY California State Motor Vehicle and Nonroad Engine Pollution Control Standards; Truck Idling... certification, inspection or any other approval relating to the control of emissions from any new motor vehicle... standards) for the control of emissions from new motor vehicles or new motor vehicle engines prior to March...

  6. Speciation Profiles and Toxic Emission Factors for Nonroad Engines: DRAFT REPORT

    Science.gov (United States)

    This document details the research and development behind how MOVES2014a estimates air toxic emissions for nonroad engines and equipment run on conventional gasoline without ethanol (E0) and gasoline blended with 10% ethanol (E10) as well as diesel fuel, compressed natural gas (C...

  7. 78 FR 721 - California State Nonroad Engine Pollution Control Standards; Transport Refrigeration Units...

    Science.gov (United States)

    2013-01-04

    ... AGENCY California State Nonroad Engine Pollution Control Standards; Transport Refrigeration Units... Transport Refrigeration Units (TRU) and TRU Generator Sets and Facilities Where TRUs Operate.'' CARB has...''), regarding its ``Airborne Toxic Control Measure for In-Use Diesel-Fueled Transport Refrigeration Units...

  8. 40 CFR 80.522 - May used motor oil be dispensed into diesel motor vehicles or nonroad diesel engines?

    Science.gov (United States)

    2010-07-01

    ... diesel motor vehicles or nonroad diesel engines? 80.522 Section 80.522 Protection of Environment... Motor Vehicle Diesel Fuel; Nonroad, Locomotive, and Marine Diesel Fuel; and ECA Marine Fuel Motor Vehicle Diesel Fuel Standards and Requirements § 80.522 May used motor oil be dispensed into diesel...

  9. 76 FR 77515 - California State Nonroad Engine Pollution Control Standards; Ocean-Going Vessels At-Berth in...

    Science.gov (United States)

    2011-12-13

    ... AGENCY California State Nonroad Engine Pollution Control Standards; Ocean-Going Vessels At-Berth in... engines operated on ocean-going vessels at-berth in California ports (``At-Berth Regulation''). The At... airborne toxic control measures (ATCM) for auxiliary diesel engines operated on ocean-going vessels at...

  10. Mitigation of PAH and nitro-PAH emissions from nonroad diesel engines.

    Science.gov (United States)

    Liu, Z Gerald; Wall, John C; Ottinger, Nathan A; McGuffin, Dana

    2015-03-17

    More stringent emission requirements for nonroad diesel engines introduced with U.S. Tier 4 Final and Euro Stage IV and V regulations have spurred the development of exhaust aftertreatment technologies. In this study, several aftertreatment configurations consisting of diesel oxidation catalysts (DOC), diesel particulate filters (DPF), Cu zeolite-, and vanadium-based selective catalytic reduction (SCR) catalysts, and ammonia oxidation (AMOX) catalysts are evaluated using both Nonroad Transient (NRTC) and Steady (8-mode NRSC) Cycles in order to understand both component and system-level effects of diesel aftertreatment on emissions of polycyclic aromatic hydrocarbons (PAH) and their nitrated derivatives (nitro-PAH). Emissions are reported for four configurations including engine-out, DOC+CuZ-SCR+AMOX, V-SCR+AMOX, and DOC+DPF+CuZ-SCR+AMOX. Mechanisms responsible for the reduction, and, in some cases, the formation of PAH and nitro-PAH compounds are discussed in detail, and suggestions are provided to minimize the formation of nitro-PAH compounds through aftertreatment design optimizations. Potency equivalency factors (PEFs) developed by the California Environmental Protection Agency are then applied to determine the impact of aftertreatment on PAH-derived exhaust toxicity. Finally, a comprehensive set of exhaust emissions including criteria pollutants, NO2, total hydrocarbons (THC), n-alkanes, branched alkanes, saturated cycloalkanes, aromatics, aldehydes, hopanes and steranes, and metals is provided, and the overall efficacy of the aftertreatment configurations is described. This detailed summary of emissions from a current nonroad diesel engine equipped with advanced aftertreatment can be used to more accurately model the impact of anthropogenic emissions on the atmosphere.

  11. Effect of biodiesel fuel on "real-world", nonroad heavy duty diesel engine particulate matter emissions, composition and cytotoxicity.

    Science.gov (United States)

    Martin, Nathan; Lombard, Melissa; Jensen, Kirk R; Kelley, Patrick; Pratt, Tara; Traviss, Nora

    2017-05-15

    Biodiesel is regarded by many as a "greener" alternative fuel to petroleum diesel with potentially lower health risk. However, recent studies examining biodiesel particulate matter (PM) characteristics and health effects are contradictive, and typically utilize PM generated by passenger car engines in laboratory settings. There is a critical need to analyze diesel and biodiesel PM generated in a "real-world" setting where heavy duty-diesel (HDD) engines and commercially purchased fuel are utilized. This study compares the mass concentrations, chemical composition and cytotoxicity of real-world PM from combustion of both petroleum diesel and a waste grease 20% biodiesel blend (B20) at a community recycling center operating HDD nonroad equipment. PM was analyzed for metals, elemental/organic carbon (EC/OC), polycyclic aromatic hydrocarbons (PAHs), and nitro-polycyclic aromatic hydrocarbons (N-PAHs). Cytotoxicity in a human lung epithelial cell line (BEAS-2B) following 24h exposure to the real-world particles was also evaluated. On average, higher concentrations for both EC and OC were measured in diesel PM. B20 PM contained significantly higher levels of Cu and Mo whereas diesel PM contained significantly higher concentrations of Pb. Principal component analysis determined Mo, Cu, and Ni were the metals with the greatest loading factor, suggesting a unique pattern related to the B20 fuel source. Total PAH concentration during diesel fuel use was 1.9 times higher than during B20 operations; however, total N-PAH concentration was 3.3 times higher during B20 use. Diesel PM cytotoxicity was 8.5 times higher than B20 PM (p<0.05) in a BEAS-2B cell line. This study contributes novel data on real-world, nonroad engine sources of metals, PAH and N-PAH species, comparing tailpipe PM vs. PM collected inside the equipment cabin. Results suggest PM generated from burning petroleum diesel in nonroad engines may be more harmful to human health, but the links between exposure

  12. The organic composition of diesel particulate matter, diesel fuel and engine oil of a non-road diesel generator.

    Science.gov (United States)

    Liang, Fuyan; Lu, Mingming; Keener, Tim C; Liu, Zifei; Khang, Soon-Jai

    2005-10-01

    Diesel-powered equipment is known to emit significant quantities of fine particulate matter to the atmosphere. Numerous organic compounds can be adsorbed onto the surfaces of these inhalable particles, among which polycyclic aromatic hydrocarbons (PAHs) are considered potential occupational carcinogens. Guidelines have been established by various agencies regarding diesel emissions and various control technologies are under development. The purpose of this study is to identify, quantify and compare the organic compounds in diesel particulate matter (DPM) with the diesel fuel and engine oil used in a non-road diesel generator. Approximately 90 organic compounds were quantified (with molecular weight ranging from 120 to 350), which include alkanes, PAHs, alkylated PAHs, alkylbenzenes and alkanoic acids. The low sulfur diesel fuel contains 61% alkanes and 7.1% of PAHs. The identifiable portion of the engine oil contains mainly the alkanoic and benzoic acids. The composition of DPM suggests that they may be originated from unburned diesel fuel, engine oil evaporation and combustion generated products. Compared with diesel fuel, DPM contains fewer fractions of alkanes and more PAH compounds, with the shift toward higher molecular weight ones. The enrichment of compounds with higher molecular weight in DPM may be combustion related (pyrogenic).

  13. 78 FR 36135 - Heavy-Duty Engine and Vehicle, and Nonroad Technical Amendments

    Science.gov (United States)

    2013-06-17

    ... source sector, after light-duty passenger cars and trucks. The final rule was published in the Federal... technologies (such as Rankine engines, electric vehicles and fuel cell vehicles), in order to generate advanced... fuel conversion regulations to provide clarity regarding the applicability of the fuel...

  14. 76 FR 38153 - California State Nonroad Engine Pollution Control Standards; Commercial Harbor Craft Regulations...

    Science.gov (United States)

    2011-06-29

    ... Innovative Strategies Division, Office of Transportation and Air Quality, U.S. Environmental Protection... strategy (DECS) determined by CARB to be the greatest feasible reduction of NO X or PM when used with the... marine engines in ferries, excursion vessels, tugboats, towboats, push boats, and multipurpose harbor...

  15. 78 FR 49963 - Heavy-Duty Engine and Vehicle and Nonroad Technical Amendments

    Science.gov (United States)

    2013-08-16

    ... within a test group based on engine code, transmission type and gear ratios, final drive ratio, and other... configurations within each test group and transmission type (instead of configurations within each base level and... performed on the basis of test group and transmission type (instead of the model-type basis specified in...

  16. Effects of Intermediate Ethanol Blends on Legacy Vehicles and Small Non-Road Engines, Report 1

    Energy Technology Data Exchange (ETDEWEB)

    Knoll, Keith [National Renewable Energy Lab. (NREL), Golden, CO (United States); West, Brian [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Clark, Wendy [National Renewable Energy Lab. (NREL), Golden, CO (United States); Graves, Ronald [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Orban, John [Battelle Memorial Inst., Columbus, OH (United States); Przesmitzki, Steve [National Renewable Energy Lab. (NREL), Golden, CO (United States); Theiss, Timothy [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2009-02-01

    This report (February 2009) is an update of the original version, which was published in October 2008. This report is the result of the U.S. Department of Energy's test program to evaluate the potential impacts of intermediate ethanol blends on legacy vehicles and other engines. The purpose of the test program is to assess the viability of using intermediate blends as a contributor to meeting national goals in the use of renewable fuels.

  17. Particle- and gas-phase PAHs toxicity equivalency quantity emitted by a non-road diesel engine with non-thermal plasma technology.

    Science.gov (United States)

    Gao, Jianbing; Ma, Chaochen; Xing, Shikai; Zhang, Yajie; Liu, Jiangquan; Feng, Hao

    2016-10-01

    Polycyclic aromatic hydrocarbon (PAH) toxicity equivalency quantity (TEQ, denoted by benzo(a)pyrene equivalent (BaPeq) concentration) is more meaningful when evaluating the influence of non-road diesel engines PAH toxicity on environment. Particle- and gas-phase PAH BaPeq concentrations were calculated based on gas chromatography-mass spectrometer (GC-MS) results and toxic equivalency factors. A non-thermal plasma (NTP) reactor was applied to a non-road diesel engine to decrease PAH TEQ content. Only the gas-phase Nap BaPeq concentration increased slightly with the action of NTP at three different generator power outputs. BaP dominated the BaPeq concentration for 15 samples with, and without NTP except in the gas-phase at 4 kW. Almost all medium molecular weight (MMW) and high molecular weight (HMW) PAH TEQs increased for particle- and gas-phases at 3 kW power output compared to 2 kW without the use of NTP. Particle-phase Nap, Acp, and AcPy (low molecular weight, LMW) TEQ were under detection at 3 and 4 kW, while gas-phase BkF, IND, DBA, and BghiP (HMW) concentrations were below the limits of detection. The most abundant PAH TEQ compounds were MMW and HMW PAHs for gas- and particle-phase while they were BaA, CHR, BbF, BaP, and IND for PM aggregation. The total BaPeq emission factors were 15.1, 141.4, and 46.5 μg m(-3) at three engine loads, respectively. Significant BaPeq concentration percentage reduction was obtained (more than 80 and 60 %) with the use of NTP for particle- and gas-phases. A high TEQ content was observed for PM aggregation (38.8, 98.4, and 50.0 μg kg(-1)) which may have caused secondary PAH toxicity emissions. With the action of NTP, the breakup of MMW and HMW into LMW PAHs led to reduction of some PAH concentrations.

  18. Physicochemical and toxicological characteristics of particulate matter emitted from a non-road diesel engine: comparative evaluation of biodiesel-diesel and butanol-diesel blends.

    Science.gov (United States)

    Zhang, Zhi-Hui; Balasubramanian, Rajasekhar

    2014-01-15

    Combustion experiments were conducted to evaluate the effects of using blends of ultralow sulfur diesel (ULSD) with biodiesel or n-butanol on physicochemical and toxicological characteristics of particulate emissions from a non-road diesel engine. The results indicated that compared to ULSD, both the blended fuels could effectively reduce the particulate mass and elemental carbon emissions, with butanol being more effective than biodiesel. The proportion of organic carbon and volatile organic compounds in particles increased for both blended fuels. However, biodiesel blended fuels showed lower total particle-phase polycyclic aromatic hydrocarbons (PAHs) emissions. The total number emissions of particles ≤560nm in diameter decreased gradually for the butanol blended fuels, but increased significantly for the biodiesel blended fuels. Both the blended fuels indicated lower soot ignition temperature and activation energy. All the particle extracts showed a decline in cell viability with the increased dose. However, the change in cell viability among test fuels is not statistically significant different with the exception of DB-4 (biodiesel-diesel blend containing 4% oxygen) used at 75% engine load. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. 77 FR 497 - Control of Emissions From New Nonroad Compression-Ignition Engines: Approval of New Scheduled...

    Science.gov (United States)

    2012-01-05

    ... catalytic converters and if the engines are at or above 130 kW then a manufacturer may not schedule the catalytic converter maintenance more frequently than 4,500 hours. In addition, should a manufacturer desire... perform during service accumulation on emission-data engines) not found under Sec. 1039.125(a)(2) and...

  20. MODELLING OF NON-ROAD TRANSIENT CYCLE

    Directory of Open Access Journals (Sweden)

    Martin Kotus

    2013-12-01

    Full Text Available The paper describes the modeling of NRTC (Non-Road Transient Cycle test procedure based on previously measured characteristics of fuel consumption, carbon monoxide (CO, carbon dioxide (CO2, hydrocarbons (HC, nitrogen oxides (NOx and particulates (PM production. It makes possible to compare the current technical condition of an internal combustion engine of an agricultural tractor with its previous state or other tractor’s engine. Based on measured characteristics, it is also possible to model any other cycle without further measurements (NRSC test procedure, cycle for specific conditions – mountain tractor, etc.. The result may thus contribute to improving the environment by reducing the production of harmful substances emitted into the air and save money due to reduced fuel consumption.

  1. New Engines for Growth

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The global financial crisis changed the global economic order—it also changed the way people think about that order.Once accepted principles and practice have now come into question or are altogether discredited.While the developed world gets its house in order,developing countries are becoming a new engine of global growth and a pulling force for advanced economies.The World Bank recently published its analysis of this trend in a book called The Day After Tomorrow:A Handbook on the Future of Economic Policy in the Developing World.Edited excerpts follow:

  2. Concepts to meet non-road stage IV / Tier 4 emission legislation; Konzepte fuer die Emissionsgesetzgebung. Non-Road Stage IV / Tier 4

    Energy Technology Data Exchange (ETDEWEB)

    Cartus, T.; Herrmuth, H.; Stein, G. [AVL List GmbH, Graz (Austria); Scherm, P. [Euromot - European Association of Internal Combustion Engine Mfrs., Frankfurt am Main (Germany)

    2007-12-15

    By December 2007, the EC will have to submit a new proposal for Stage IV emissions limits for Non-Road Mobile Machinery. Industry is committed to contributing to this process and has asked AVL to carry out a study as a neutral engineering company. The main topics of this study are described in this article. (orig.)

  3. An overview of non-road equipment emissions in China

    Science.gov (United States)

    Wang, Fan; Li, Zhen; Zhang, Kaishan; Di, Baofeng; Hu, Baomei

    2016-05-01

    As the vehicle population has dramatically increased in China in the past two decades, vehicle emissions have become one of the major sources to air pollution across the entire country, especially for the metropolitan cities such as Beijing and Shanghai. Most of the non-road equipment are diesel-fueled and have been proved to be a key source for NOx and PM emissions, contributing significantly to the formation of haze/smog. Therefore, an accurate estimation of emission inventory from non-road equipment is essential for air quality improvement policy making, which mainly depends on the data availability of equipment population, activity, and emissions factor. Compared to on-road vehicles, less studies regarding emissions characterization have been conducted and investigated for non-road mobile sources in China. Thus, in order to identify the data gaps and future research needs, the objective of this study is to review the current status of research in non-road mobile emissions. Five types of non-road equipment were addressed in this study, including agricultural equipment, industrial equipment, river/ocean-going vessels, locomotives, and commercial airplanes, with a focus on the former two. The equipment are further classified mainly based on national standards and data availability to account for fuel type, job duties and others. This investigation has found that the research regarding emissions from non-road equipment is still at its early stage and there is a huge data gap for both activity and emissions factors. For most of the study, data used for emission inventory estimation were based on either literature with similar equipment or as-developed emissions models such as NONROAD or CORPERT. The representativeness of these data to the localities was not much discussed in those studies, which might have weakened the accuracy of the estimated emission inventory. For future study, real-world in-use measurements of activities and emissions for the non-road equipment

  4. Test/QA plan for the verification testing of alternative or reformulated liquid fuels, fuel additives, fuel emulsions, and lubricants for highway and nonroad use heavy-duty diesel engines

    Science.gov (United States)

    This Environmental Technology Verification Program test/QA plan for heavy-duty diesel engine testing at the Southwest Research Institute’s Department of Emissions Research describes how the Federal Test Procedure (FTP), as listed in 40 CFR Part 86 for highway engines and 40 CFR P...

  5. 75 FR 8056 - California State Nonroad Engine Pollution Control Standards; California New Nonroad Compression...

    Science.gov (United States)

    2010-02-23

    ... Air Act Section 209 Proceedings In Motor and Equip. Mfrs. Assoc. v. EPA, 627 F.2d 1095 (D.C. Cir. 1979... * * *.\\16\\ \\16\\ Motor and Equip. Mfrs. Assoc. v. EPA (MEMA I), 627 F.2d 1095, 1122 (D.C. Cir. 1979). The...

  6. Engineering growth factors for regenerative medicine applications.

    Energy Technology Data Exchange (ETDEWEB)

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

    2016-01-15

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

  7. Effects of Engineered Nanomaterials on Plants Growth: An Overview

    OpenAIRE

    Farzad Aslani; Samira Bagheri; Nurhidayatullaili Muhd Julkapli; Abdul Shukor Juraimi; Farahnaz Sadat Golestan Hashemi; Ali Baghdadi

    2014-01-01

    Rapid development and wide applications of nanotechnology brought about a significant increment on the number of engineered nanomaterials (ENs) inevitably entering our living system. Plants comprise of a very important living component of the terrestrial ecosystem. Studies on the influence of engineered nanomaterials (carbon and metal/metal oxides based) on plant growth indicated that in the excess content, engineered nanomaterials influences seed germination. It assessed the shoot-to-root ra...

  8. Growth of Engineering Education in India: Status, Issues, and Challenges

    Science.gov (United States)

    Choudhury, Pradeep Kumar

    2016-01-01

    This article examines the growth of engineering education in India in the post-economic reform period using the secondary data published by Ministry of Human Resource Development, University Grants Commission and All India Council for Technical Education. Particularly, this article has focused on three important dimensions of engineering and…

  9. Inter-textual Vocabulary Growth Patterns for Marine Engineering English

    Institute of Scientific and Technical Information of China (English)

    JINGJIE LI; ZHIWEI FENG

    2011-01-01

    This paper explores two fundamental issues concerning the inter-textual vocabulary growth patterns for Marine Engineering English, viz. vocabulary growth models and newly occurring vocabulary distributions in cumulative texts. On the basis of the DMMEE (Dalian Maritime University Marine Engineering English) corpus, four mathematical models (Brunet's, Guiraud's, Tuldava's, and Herdan's models) are tested against the empirical vocabulary growth curve for Marine Engineering English. A new growth model based on the logarithmic function and the power law is presented. The theoretical mean vocabulary size and the 95% upper and lower bound values are calculated and plotted as functions of the sample size. Being significant in explicit EFL teaching and learning, the new growth model can make accurate estimates not only on the vocabulary size and its intervals for a given textbook but also on the volume of texts that are needed to produce a particular vocabulary size.

  10. Effects of engineered nanomaterials on plants growth: an overview.

    Science.gov (United States)

    Aslani, Farzad; Bagheri, Samira; Muhd Julkapli, Nurhidayatullaili; Juraimi, Abdul Shukor; Hashemi, Farahnaz Sadat Golestan; Baghdadi, Ali

    2014-01-01

    Rapid development and wide applications of nanotechnology brought about a significant increment on the number of engineered nanomaterials (ENs) inevitably entering our living system. Plants comprise of a very important living component of the terrestrial ecosystem. Studies on the influence of engineered nanomaterials (carbon and metal/metal oxides based) on plant growth indicated that in the excess content, engineered nanomaterials influences seed germination. It assessed the shoot-to-root ratio and the growth of the seedlings. From the toxicological studies to date, certain types of engineered nanomaterials can be toxic once they are not bound to a substrate or if they are freely circulating in living systems. It is assumed that the different types of engineered nanomaterials affect the different routes, behavior, and the capability of the plants. Furthermore, different, or even opposing conclusions, have been drawn from most studies on the interactions between engineered nanomaterials with plants. Therefore, this paper comprehensively reviews the studies on the different types of engineered nanomaterials and their interactions with different plant species, including the phytotoxicity, uptakes, and translocation of engineered nanomaterials by the plant at the whole plant and cellular level.

  11. Engineering crystal growth of calcium hydrogenphosphate dihydrate

    Energy Technology Data Exchange (ETDEWEB)

    Sikiric, M.; Babic-Ivancic, V. [Institut Rudjer Boskovic, Zagreb (Croatia); Milat, O. [Zagreb Univ. (Croatia). Inst. za Fiziku; Sarig, S.; Fueredi-Milhofer, H. [Hebrew Univ., Jerusalem (Israel). Inst. of Applied Chemistry

    2001-07-01

    The factors underlying calcium hydrogenphosphate dihydrate (CaHPO{sub 4}.2H{sub 2}O, DCPD) interactions with several structurally different additives: glutamic and aspartic acid, sodium citrate, hexaammonium tetrapolyphosphate, calcium phytate and polyaspartic acid were studied. DCPD crystals were prepared under controlled conditions by fast mixing of the anionic and cationic reactant solutions and subsequent growth without further stirring in the course of 24 hours at 37 C. The initial conditions were c(CaCl{sub 2}) = c(Na{sub 2}HPO{sub 4}) = 0.021 mol dm{sup -3}, c(NaCl) = 0.3 mol dm{sup -3}, pH{sub i} 5.5. The respective additive was added to the anionic component prior to pH adjustment. Crystals were characterized by X-ray diffraction, while their morphology was observed by optical and scanning electron microscopy (SEM). The Miller indices of the crystal faces were determined from SEM micrographs, after the orientation of the most prominent face was ascertained by the Weissenberg method. Mechanism of additive-DCPD crystals interaction depends on size and structure of additive molecule, structural fit between organic molecule and the ionic structure of particular crystal face. Small molecules (ions) specifically adsorb on lateral faces by electrostatic interactions, while macromolecules and molecules with hindered structure specifically adsorb on dominant (010) face, for which certain degree of structural fit is necessary. (orig.)

  12. Data structure for estimating emissions from non-road sources

    Energy Technology Data Exchange (ETDEWEB)

    Sorenson, S. C.; Kalivoda, M.; Vacarro, R.; Trozzi, C.; Samaras, Z.; Lewis, C.A.

    1997-03-01

    The work described in the following is a portion of the MEET project (Methodologies for Estimation Air Pollutant Emissions from Transport). The overall goal of the MEET project is to consolidate and present methodologies which can be used to estimate air pollutant emissions from various types of traffic sources. One of the goals of MEET is to provide methodologies to be used in the COMMUTE project also funded by DG VII. COMMUTE is developing computer software which can be used to provide emissions inventories on the European scale. Although COMMUTE is viewed as a prime user of the information generated in MEET, the MEET results are intended to be used in a broader area, and on both smaller and larger spatial scales. The methodologies and data presented will be useful for planners on a more local scale than a national or continental basis. While most attention in previous years has been concentrated on emissions from road transport, it has become increasingly apparent in later years that the so-called off road transportation contributes significantly to the emission of air pollutants. The three most common off-road traffic modes are Air Traffic, Rail Traffic, and Ship or Marine traffic. In the following, the basic structure of the methods for estimating the emissions from these sectors will be given and of the input and output data associated with these calculations. The structures will of necessity be different for the different types of traffic. The data structures in the following reflect these variations and uncertainties. In some instances alternative approaches to emissions estimation will be suggested. The user must evaluate the amount and reliability of available data for the application at hand, and select the method which would be expected to give the highest accuracy. In any event, a large amount of uncertainty is inherent in the estimation of emissions from the non-road traffic sources, particularly those involving rail and maritime transport. (EG)

  13. Data structure for estimating emissions from non-road sources

    Energy Technology Data Exchange (ETDEWEB)

    Sorenson, S. C.; Kalivoda, M.; Vacarro, R.; Trozzi, C.; Samaras, Z.; Lewis, C.A.

    1997-03-01

    The work described in the following is a portion of the MEET project (Methodologies for Estimation Air Pollutant Emissions from Transport). The overall goal of the MEET project is to consolidate and present methodologies which can be used to estimate air pollutant emissions from various types of traffic sources. One of the goals of MEET is to provide methodologies to be used in the COMMUTE project also funded by DG VII. COMMUTE is developing computer software which can be used to provide emissions inventories on the European scale. Although COMMUTE is viewed as a prime user of the information generated in MEET, the MEET results are intended to be used in a broader area, and on both smaller and larger spatial scales. The methodologies and data presented will be useful for planners on a more local scale than a national or continental basis. While most attention in previous years has been concentrated on emissions from road transport, it has become increasingly apparent in later years that the so-called off road transportation contributes significantly to the emission of air pollutants. The three most common off-road traffic modes are Air Traffic, Rail Traffic, and Ship or Marine traffic. In the following, the basic structure of the methods for estimating the emissions from these sectors will be given and of the input and output data associated with these calculations. The structures will of necessity be different for the different types of traffic. The data structures in the following reflect these variations and uncertainties. In some instances alternative approaches to emissions estimation will be suggested. The user must evaluate the amount and reliability of available data for the application at hand, and select the method which would be expected to give the highest accuracy. In any event, a large amount of uncertainty is inherent in the estimation of emissions from the non-road traffic sources, particularly those involving rail and maritime transport. (EG)

  14. 40 CFR 89.116 - Engine families.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine families. 89.116 Section 89.116... EMISSIONS FROM NEW AND IN-USE NONROAD COMPRESSION-IGNITION ENGINES Emission Standards and Certification Provisions § 89.116 Engine families. (a) A manufacturer's product line is divided into engine families...

  15. Rayleigh Taylor Instability Growth in NIC Capsules with Engineered Defects

    Science.gov (United States)

    Peterson, K. J.; Hammel, B. A.; Suter, L. J.; Clark, D. S.; Farley, D. R.; Landen, O. L.; Scott, H.; Moreno, K.; Vesey, R. A.; Herrmann, M. C.; Nakhleh, C. W.; Golovkin, I.; Regan, S. P.; Epstein, R.

    2011-10-01

    In order to achieve thermonuclear burn and energy gain in ICF capsules, the growth of hydrodynamic instabilities must be understood and controlled. Experiments are planned to measure time dependent hydrodynamic instability growth of engineered defects on the surface of NIC capsules using x-ray radiography. We will present an analysis of synthetic radiography from 2D and 3D HYDRA simulations with various x-ray drive fluxes and show how these results will be used to assess code predictions of instability growth and mix. We will also discuss how these results correlate with capsule performance and observables from hot spot self emission imaging and Ge spectroscopy. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  16. Nonroad developed land in the United States Pacific Northwest for 2001

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This spatial data set was created by the U.S. Geological Survey (USGS) to represent the extent of non-road developed land in the Pacific Northwest region of the...

  17. Catalyst shape engineering for anisotropic cross-sectioned nanowire growth

    Science.gov (United States)

    Calahorra, Yonatan; Kelrich, Alexander; Cohen, Shimon; Ritter, Dan

    2017-01-01

    The ability to engineer material properties at the nanoscale is a crucial prerequisite for nanotechnology. Hereunder, we suggest and demonstrate a novel approach to realize non-hemispherically shaped nanowire catalysts, subsequently used to grow InP nanowires with a cross section anisotropy ratio of up to 1:1.8. Gold was deposited inside high aspect ratio nanotrenches in a 5 nm thick SiNx selective area mask; inside the growth chamber, upon heating to 455 °C, the thin gold stripes agglomerated, resulting in an ellipsoidal dome (hemiellipsoid). The initial shape of the catalyst was preserved during growth to realize asymmetrically cross-sectioned nanowires. Moreover, the crystalline nature of the nanowire side facets was found to depend on the nano-trench orientation atop the substrate, resulting in hexagonal or octagonal cross-sections when the nano-trenches are aligned or misaligned with the [1¯10] orientation atop a [111]B substrate. These results establish the role of catalyst shape as a unique tool to engineer nanowire growth, potentially allowing further control over its physical properties.

  18. 77 FR 20388 - California State Nonroad Engine Pollution Control Standards; Large Spark-Ignition (LSI) Engines...

    Science.gov (United States)

    2012-04-04

    ... America (``A4A''). A4A comments that California's LSI regulations as applicable to airport ground support.... Other Issues Airlines for America (``A4A'') has provided comments opposing EPA's grant of authorization for California's LSI regulations. The reasons A4A provides in its comments are outside the scope...

  19. Robotic Scaffolds for Tissue Engineering and Organ Growth

    Science.gov (United States)

    Stoica, Adrian

    2011-01-01

    The aim of tissue engineering (TE) is to restore tissue and organ functions with minimal host rejection. TE is seen as a future solution to solve the crisis of donor organs for transplant, which faces a shortage expected only to increase in the future. In this innovation, a flexible and configurable scaffold has been conceived that mechanically stresses cells that are seeded on it, stimulating them to increased growth. The influence of mechanical stress/ loading on cell growth has been observed on all forms of cells. For example, for cartilages, studies in animals, tissue explants, and engineered tissue scaffolds have all shown that cartilage cells (chondrocytes) modify their extracellular matrix in response to loading. The chondrocyte EMC production response to dynamics of the physical environment (in vivo cartilage development) illustrates a clear benefit (better growth) when stressed. It has been shown that static and dynamic compression regulates PRG4 biosynthesis by cartilage explants. Mechanical tissue stimulation is beneficial and (flexible) scaffolds with movable components, which are able to induce mechanical stimulation, offer advantages over the fixed, rigid scaffold design. In addition to improved cell growth from physical/mechanical stimulation, additional benefits include the ability to increase in size while preserving shape, or changing shape. By making scaffolds flexible, allowing relative movement between their components, adding sensing (e.g., for detecting response of cells to drug release and to mechanical actions), building controls for drug release and movement, and building even simple algorithms for mapping sensing to action, these structures can actually be made into biocompatible and biodegradable robots. Treating them as robots is a perspective shift that may offer advantages in the design and exploitation of these structures of the future.

  20. Nonroad developed land in the United States Pacific Northwest for 2001 summarized for NHDPlus v2 catchments

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This spatial data set was created by the U.S. Geological Survey (USGS) to represent the area of non-road developed land within each incremental watershed delineated...

  1. Energy efficient non-road hybrid electric vehicles advanced modeling and control

    CERN Document Server

    Unger, Johannes; Jakubek, Stefan

    2016-01-01

    Analyzing the main problems in the real-time control of parallel hybrid electric powertrains in non-road applications, which work in continuous high dynamic operation, this book gives practical insight in to how to maximize the energetic efficiency and drivability of such powertrains. The book addresses an energy management control structure, which considers all constraints of the physical powertrain and uses novel methodologies for the prediction of the future load requirements to optimize the controller output in terms of an entire work cycle of a non-road vehicle. The load prediction includes a methodology for short term loads as well as for an entire load cycle by means of a cycle detection. A maximization of the energetic efficiency can so be achieved, which is simultaneously a reduction in fuel consumption and exhaust emissions. Readers will gain a deep insight into the necessary topics to be considered in designing an energy and battery management system for non-road vehicles and that only a combinatio...

  2. Tissue Engineering Using Transfected Growth-Factor Genes

    Science.gov (United States)

    Madry, Henning; Langer, Robert S.; Freed, Lisa E.; Trippel, Stephen; Vunjak-Novakovic, Gordana

    2005-01-01

    A method of growing bioengineered tissues includes, as a major component, the use of mammalian cells that have been transfected with genes for secretion of regulator and growth-factor substances. In a typical application, one either seeds the cells onto an artificial matrix made of a synthetic or natural biocompatible material, or else one cultures the cells until they secrete a desired amount of an extracellular matrix. If such a bioengineered tissue construct is to be used for surgical replacement of injured tissue, then the cells should preferably be the patient s own cells or, if not, at least cells matched to the patient s cells according to a human-leucocyteantigen (HLA) test. The bioengineered tissue construct is typically implanted in the patient's injured natural tissue, wherein the growth-factor genes enhance metabolic functions that promote the in vitro development of functional tissue constructs and their integration with native tissues. If the matrix is biodegradable, then one of the results of metabolism could be absorption of the matrix and replacement of the matrix with tissue formed at least partly by the transfected cells. The method was developed for articular chondrocytes but can (at least in principle) be extended to a variety of cell types and biocompatible matrix materials, including ones that have been exploited in prior tissue-engineering methods. Examples of cell types include chondrocytes, hepatocytes, islet cells, nerve cells, muscle cells, other organ cells, bone- and cartilage-forming cells, epithelial and endothelial cells, connective- tissue stem cells, mesodermal stem cells, and cells of the liver and the pancreas. Cells can be obtained from cell-line cultures, biopsies, and tissue banks. Genes, molecules, or nucleic acids that secrete factors that influence the growth of cells, the production of extracellular matrix material, and other cell functions can be inserted in cells by any of a variety of standard transfection techniques.

  3. Engineering

    National Research Council Canada - National Science Library

    Includes papers in the following fields: Aerospace Engineering, Agricultural Engineering, Chemical Engineering, Civil Engineering, Electrical Engineering, Environmental Engineering, Industrial Engineering, Materials Engineering, Mechanical...

  4. Growth factor releasing scaffolds for cartilage tissue engineering

    NARCIS (Netherlands)

    Sohier, Jerome

    2006-01-01

    Over the last century, life expectancy has increased at a rapid pace resulting in an increase of articular cartilage disorders. To solve this problem, extensive research is currently performed using tissue engineering approaches. Cartilage tissue engineering aims to reconstruct this tissue both stru

  5. Engines of Growth in the U.S. Economy

    NARCIS (Netherlands)

    Ten Raa, T.; Wolff, E.N.

    2000-01-01

    There is good reason to believe that R&D influences on TFP growth in other sectors are indirect.For R&D to spill over, it must first be successful in the home sector.Indeed, observed spillovers conform better to TFP growth than to R&D in the upstream sectors.Sectoral TFP growth rates are thus

  6. 78 FR 724 - California State Nonroad Engine Pollution Control Standards; Off-Highway Recreational Vehicles...

    Science.gov (United States)

    2013-01-04

    ... vehicles. Second, the amendments reclassified sand cars, off-road utility vehicles and off-road sport... standard, (2) a within-the- scope determination for the reclassification of sand cars, off-road sport... standards will be, in the aggregate, at least as protective of public health and welfare as applicable...

  7. 78 FR 58089 - California State Nonroad Engine Pollution Control Standards; Off-Road Compression Ignition...

    Science.gov (United States)

    2013-09-20

    ... authorization of the Fleet Requirements as amended in 2010. The legal framework for this decision stems from the... considered under section 209(e)(2)(A). \\8\\ See, e.g., Motor and Equip. Mfrs Assoc. v. EPA, 627 F.2d 1095 (D.C...

  8. 76 FR 5586 - California State Motor Vehicle and Nonroad Engine Pollution Control Standards; Mobile Cargo...

    Science.gov (United States)

    2011-02-01

    ... Equipment). CARB's Mobile Cargo Handling Equipment requirements are designed to use best available control... Alexander at (202) 343-9540, to learn if a hearing will be held or may check the following webpage for an... restricted by statute. EPA's Office of Transportation and Air Quality also maintains a webpage that...

  9. 78 FR 36369 - Heavy-Duty Engine and Vehicle, and Nonroad Technical Amendments

    Science.gov (United States)

    2013-06-17

    ...\\ See 49 CFR 553.21. \\4\\ Optical character recognition (OCR) is the process of converting an image of... that the documents submitted be scanned using the Optical Character Recognition (OCR) process, thus... benefits of the standards achieved during this critical initial phase of the program by providing the...

  10. 76 FR 77521 - California State Nonroad Engine Pollution Control Standards; Commercial Harbor Craft Regulations...

    Science.gov (United States)

    2011-12-13

    ... strategy (DECS) determined by CARB to be the greatest feasible reduction of NO X or PM. For in-use harbor..., push boats, and multipurpose harbor craft. Those harbor craft are required to meet emission limits... owners and operators may opt to meet requirements by implementing alternative emission control strategies...

  11. 77 FR 72851 - California State Nonroad Engine Pollution Control Standards; Portable Equipment Registration...

    Science.gov (United States)

    2012-12-06

    ....regulations.gov or in hard copy at the Air and Radiation Docket in the EPA Headquarters Library, EPA West... will give appropriate consideration to safety factors (including the potential increased risk of burn... proof must take account of the nature of the risk of error involved in any given decision, and...

  12. 40 CFR 89.603 - General requirements for importation of nonconforming nonroad engines.

    Science.gov (United States)

    2010-07-01

    ... that pollutant applicable to the OP year for the appropriate power category. (3) ICIs may not generate... model year, except as allowed by paragraph (e)(5) of this section. For ICIs owned by a parent...

  13. 78 FR 38970 - California State Nonroad Engine Pollution Control Standards; Within-the-Scope Determination for...

    Science.gov (United States)

    2013-06-28

    ... Measure for In-Use Diesel-Fueled Transport Refrigeration Units (TRU) and TRU Generator Sets and Facilities... Control Measure for In-Use Diesel-Fueled Transport Refrigeration Units (TRU) and TRU Generator Sets and... Amendments to California's ``Airborne Toxic Control Measure for In-Use Diesel-Fueled Transport Refrigeration...

  14. Immobilization and Application of Electrospun Nanofiber Scaffold-based Growth Factor in Bone Tissue Engineering.

    Science.gov (United States)

    Chen, Guobao; Lv, Yonggang

    2015-01-01

    Electrospun nanofibers have been extensively used in growth factor delivery and regenerative medicine due to many advantages including large surface area to volume ratio, high porosity, excellent loading capacity, ease of access and cost effectiveness. Their relatively large surface area is helpful for cell adhesion and growth factor loading, while storage and release of growth factor are essential to guide cellular behaviors and tissue formation and organization. In bone tissue engineering, growth factors are expected to transmit signals that stimulate cellular proliferation, migration, differentiation, metabolism, apoptosis and extracellular matrix (ECM) deposition. Bolus administration is not always an effective method for the delivery of growth factors because of their rapid diffusion from the target site and quick deactivation. Therefore, the integration of controlled release strategy within electrospun nanofibers can provide protection for growth factors against in vivo degradation, and can manipulate desired signal at an effective level with extended duration in local microenvironment to support tissue regeneration and repair which normally takes a much longer time. In this review, we provide an overview of growth factor delivery using biomimetic electrospun nanofiber scaffolds in bone tissue engineering. It begins with a brief introduction of different kinds of polymers that were used in electrospinning and their applications in bone tissue engineering. The review further focuses on the nanofiber-based growth factor delivery and summarizes the strategies of growth factors loading on the nanofiber scaffolds for bone tissue engineering applications. The perspectives on future challenges in this area are also pointed out.

  15. 40 CFR 1048.301 - When must I test my production-line engines?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false When must I test my production-line...) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, LARGE NONROAD SPARK-IGNITION ENGINES Testing Production-line Engines § 1048.301 When must I test my production-line engines? (a) If you produce...

  16. International Trade as an Engine of Growth in Developing Countries ...

    African Journals Online (AJOL)

    First Lady

    2013-06-30

    Jun 30, 2013 ... The primary objective of the study is to test the impact of international trade on ... relationship between trade and economic growth, and the result vary accordingly. ..... http://www.jubileeastralia.org/512 Jubilee Debt Jargon. Php (April. 4, 2007). ... Review of Economics and Business, Vol. 43, April – June ...

  17. GOVERNMENT EXPENDITURE ON ENGINEERING CONSTRUCTION, COMMUNICATION AND TRANSPORTATION: EVALUATION OF IMPACT ON ECONOMIC GROWTH IN NIGERIA

    Directory of Open Access Journals (Sweden)

    ALAMEZIEM KELECHI STANLEY

    2012-04-01

    Full Text Available This work tries to assess the impact of government investment in engineering construction, communication technology and transportation on economic growth in Nigeria. One null hypothesis guided the study and data was collected from 1977 to 2008 from Central Bank of Nigeria statistical bulletin. Data were analysed using regression, F and t tests, stationary and co-integration tests. Results revealed that increases in government expenditure in engineering construction impacted more significantly on economic growth than their expenditureon transport and communication. Increased expenditure on all sectors was recommended especially on engineering construction. In addition policy modifications are needed to ensure that government expenditure on the transportation and communication sector achieve greater impacts on economic growth.

  18. A New Genetically Engineered Vaccine for Animal Growth Promotion

    Institute of Scientific and Technical Information of China (English)

    徐文忠; 杜念兴; 李光地; 汪垣; 李载平

    1994-01-01

    The chemically synthesized somatostatin (ss) gene was fused in phase with the 3′-end ofhepatitis B virus surface antigen (HBsAg) gene.The fusion gene HBs/ss was then recomhined into thegenome of vaccinia virus.This recombinant virus (w-HBs/ss) can express hybrid HBsAg/ss particles whichpresent ss determinants on their surfaces,thereby bearing a good immunogenicity.This new strategical vac-cine of ss can elicit the production of antibody capable of neutralizing ss in the plasma,and consequently en-hance the growth of animals.

  19. Growth factor delivery-based tissue engineering: general approaches and a review of recent developments.

    Science.gov (United States)

    Lee, Kangwon; Silva, Eduardo A; Mooney, David J

    2011-02-06

    The identification and production of recombinant morphogens and growth factors that play key roles in tissue regeneration have generated much enthusiasm and numerous clinical trials, but the results of many of these trials have been largely disappointing. Interestingly, the trials that have shown benefit all contain a common denominator, the presence of a material carrier, suggesting strongly that spatio-temporal control over the location and bioactivity of factors after introduction into the body is crucial to achieve tangible therapeutic effect. Sophisticated materials systems that regulate the biological presentation of growth factors represent an attractive new generation of therapeutic agents for the treatment of a wide variety of diseases. This review provides an overview of growth factor delivery in tissue engineering. Certain fundamental issues and design strategies relevant to the material carriers that are being actively pursued to address specific technical objectives are discussed. Recent progress highlights the importance of materials science and engineering in growth factor delivery approaches to regenerative medicine.

  20. Solvent engineering towards controlled grain growth in perovskite planar heterojunction solar cells.

    Science.gov (United States)

    Rong, Yaoguang; Tang, Zhongjia; Zhao, Yufeng; Zhong, Xin; Venkatesan, Swaminathan; Graham, Harrison; Patton, Matthew; Jing, Yan; Guloy, Arnold M; Yao, Yan

    2015-06-28

    We report an effective solvent engineering process to enable controlled perovskite crystal growth and a wider window for processing uniform and dense methyl ammonium lead iodide (MAPbI3) perovskite films. Planar heterojunction solar cells fabricated with this method demonstrate hysteresis-free performance with a power conversion efficiency around 10%. The crystal structure of an organic-based Pb iodide intermediate phase is identified for the first time, which is critical in controlling the crystal growth and optimizing thin film morphology.

  1. Growth of genetically engineered Pseudomonas aeruginosa and Pseudomonas putida in soil and rhizosphere.

    OpenAIRE

    Yeung, K H; Schell, M A; Hartel, P G

    1989-01-01

    The effect of the addition of a recombinant plasmid containing the pglA gene encoding an alpha-1,4-endopolygalacturonase from Pseudomonas solanacearum on the growth of Pseudomonas aeruginosa and Pseudomonas putida in soil and rhizosphere was determined. Despite a high level of polygalacturonase production by genetically engineered P. putida and P. aeruginosa, the results suggest that polygalacturonase production had little effect on the growth of these strains in soil or rhizosphere.

  2. Driving and engine cycles

    CERN Document Server

    Giakoumis, Evangelos G

    2017-01-01

    This book presents in detail the most important driving and engine cycles used for the certification and testing of new vehicles and engines around the world. It covers chassis and engine-dynamometer cycles for passenger cars, light-duty vans, heavy-duty engines, non-road engines and motorcycles, offering detailed historical information and critical review. The book also provides detailed examples from SI and diesel engines and vehicles operating during various cycles, with a focus on how the engine behaves during transients and how this is reflected in emitted pollutants, CO2 and after-treatment systems operation. It describes the measurement methods for the testing of new vehicles and essential information on the procedure for creating a driving cycle. Lastly, it presents detailed technical specifications on the most important chassis-dynamometer cycles around the world, together with a direct comparison of those cycles.

  3. Bioactive electrospun scaffolds delivering growth factors and genes for tissue engineering applications

    NARCIS (Netherlands)

    Ji, W.; Sun, Y.; Yang, F.; Beucken, J.J.J.P van den; Fan, M.; Chen, Z.; Jansen, J.A.

    2011-01-01

    A biomaterial scaffold is one of the key factors for successful tissue engineering. In recent years, an increasing tendency has been observed toward the combination of scaffolds and biomolecules, e.g. growth factors and therapeutic genes, to achieve bioactive scaffolds, which not only provide physic

  4. 40 CFR 1054.301 - When must I test my production-line engines?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false When must I test my production-line...) AIR POLLUTION CONTROLS CONTROL OF EMISSIONS FROM NEW, SMALL NONROAD SPARK-IGNITION ENGINES AND EQUIPMENT Production-line Testing § 1054.301 When must I test my production-line engines? (a) If you...

  5. 77 FR 72846 - California State Nonroad Engine Pollution Control Standards; In-Use Portable Diesel Engines 50...

    Science.gov (United States)

    2012-12-06

    ... cancer, chronic bronchitis, asthma and fewer hospital visits caused by pneumonia and asthma-related... authority ``shall take effect after such period as the Administrator finds necessary to permit the... the technology before the standards go into effect. The latter scenario also requires...

  6. Cartilage tissue engineering: Role of mesenchymal stem cells along with growth factors & scaffolds

    Directory of Open Access Journals (Sweden)

    M B Gugjoo

    2016-01-01

    Full Text Available Articular cartilage injury poses a major challenge for both the patient and orthopaedician. Articular cartilage defects once formed do not regenerate spontaneously, rather replaced by fibrocartilage which is weaker in mechanical competence than the normal hyaline cartilage. Mesenchymal stem cells (MSCs along with different growth factors and scaffolds are currently incorporated in tissue engineering to overcome the deficiencies associated with currently available surgical methods and to facilitate cartilage healing. MSCs, being readily available with a potential to differentiate into chondrocytes which are enhanced by the application of different growth factors, are considered for effective repair of articular cartilage after injury. However, therapeutic application of MSCs and growth factors for cartilage repair remains in its infancy, with no comparative clinical study to that of the other surgical techniques. The present review covers the role of MSCs, growth factors and scaffolds for the repair of articular cartilage injury.

  7. Metabolic engineering of chloroplasts for artemisinic acid biosynthesis and impact on plant growth

    Indian Academy of Sciences (India)

    Bhawna Saxena; Mayavan Subramaniyan; Karan Malhotra; Neel Sarovar Bhavesh; Shobha Devi Potlakayala; Shashi Kumar

    2014-03-01

    Chloroplasts offer high-level transgene expression and transgene containment due to maternal inheritance, and are ideal hosts for biopharmaceutical biosynthesis via multigene engineering. To exploit these advantages, we have expressed 12 enzymes in chloroplasts for the biosynthesis of artemisinic acid (precursor of artemisinin, antimalarial drug) in an alternative plant system. Integration of transgenes into the tobacco chloroplast genome via homologous recombination was confirmed by molecular analysis, and biosynthesis of artemisinic acid in plant leaf tissues was detected with the help of 13C NMR and ESI-mass spectrometry. The excess metabolic flux of isopentenyl pyrophosphate generated by an engineered mevalonate pathway was diverted for the biosynthesis of artemisinic acid. However, expression of megatransgenes impacted the growth of the transplastomic plantlets. By combining two exogenous pathways, artemisinic acid was produced in transplastomic plants, which can be improved further using better metabolic engineering strategies for commercially viable yield of desirable isoprenoid products.

  8. Photoreceptor Mediated Plant Growth Responses: Implications for Photoreceptor Engineering toward Improved Performance in Crops

    Directory of Open Access Journals (Sweden)

    Ophilia I. L. Mawphlang

    2017-07-01

    Full Text Available Rising temperatures during growing seasons coupled with altered precipitation rates presents a challenging task of improving crop productivity for overcoming such altered weather patterns and cater to a growing population. Light is a critical environmental factor that exerts a powerful influence on plant growth and development ranging from seed germination to flowering and fruiting. Higher plants utilize a suite of complex photoreceptor proteins to perceive surrounding red/far-red (phytochromes, blue/UV-A (cryptochromes, phototropins, ZTL/FKF1/LKP2, and UV-B light (UVR8. While genomic studies have also shown that light induces extensive reprogramming of gene expression patterns in plants, molecular genetic studies have shown that manipulation of one or more photoreceptors can result in modification of agronomically beneficial traits. Such information can assist researchers to engineer photoreceptors via genome editing technologies to alter expression or even sensitivity thresholds of native photoreceptors for targeting aspects of plant growth that can confer superior agronomic value to the engineered crops. Here we summarize the agronomically important plant growth processes influenced by photoreceptors in crop species, alongwith the functional interactions between different photoreceptors and phytohormones in regulating these responses. We also discuss the potential utility of synthetic biology approaches in photobiology for improving agronomically beneficial traits of crop plants by engineering designer photoreceptors.

  9. Scaffolds for Growth Factor Delivery as Applied to Bone Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Keith A. Blackwood

    2012-01-01

    Full Text Available There remains a substantial shortfall in the treatment of severe skeletal injuries. The current gold standard of autologous bone grafting from the same patient has many undesirable side effects associated such as donor site morbidity. Tissue engineering seeks to offer a solution to this problem. The primary requirements for tissue-engineered scaffolds have already been well established, and many materials, such as polyesters, present themselves as potential candidates for bone defects; they have comparable structural features, but they often lack the required osteoconductivity to promote adequate bone regeneration. By combining these materials with biological growth factors, which promote the infiltration of cells into the scaffold as well as the differentiation into the specific cell and tissue type, it is possible to increase the formation of new bone. However due to the cost and potential complications associated with growth factors, controlling the rate of release is an important design consideration when developing new bone tissue engineering strategies. This paper will cover recent research in the area of encapsulation and release of growth factors within a variety of different polymeric scaffolds.

  10. Extracellular matrix and growth factor engineering for controlled angiogenesis in regenerative medicine.

    Energy Technology Data Exchange (ETDEWEB)

    Martino, Mikael M.; Brkic, Sime; Bovo, Emmanuela; Burger, Maximilian; Schaefer, Dirk J.; Wolff, Thomas; Gurke, Lorenz; Briquez, Priscilla S.; Larsson, Hans M.; Gianni-Barrera, Roberto; Hubbell, Jeffrey A.; Banfi, Andrea

    2015-04-01

    Blood vessel growth plays a key role in regenerative medicine, both to restore blood supply to ischemic tissues and to ensure rapid vascularization of clinical-size tissue-engineered grafts. For example, vascular endothelial growth factor (VEGF) is the master regulator of physiological blood vessel growth and is one of the main molecular targets of therapeutic angiogenesis approaches. However, angiogenesis is a complex process and there is a need to develop rational therapeutic strategies based on a firm understanding of basic vascular biology principles, as evidenced by the disappointing results of initial clinical trials of angiogenic factor delivery. In particular, the spatial localization of angiogenic signals in the extracellular matrix (ECM) is crucial to ensure the proper assembly and maturation of new vascular structures. Here, we discuss the therapeutic implications of matrix interactions of angiogenic factors, with a special emphasis on VEGF, as well as provide an overview of current approaches, based on protein and biomaterial engineering that mimic the regulatory functions of ECM to optimize the signaling microenvironment of vascular growth factors.

  11. Extracellular matrix and growth factor engineering for controlled angiogenesis in regenerative medicine

    Directory of Open Access Journals (Sweden)

    Mikaël M Martino

    2015-04-01

    Full Text Available Blood vessel growth plays a key role in regenerative medicine, both to restore blood supply to ischemic tissues and to ensure rapid vascularization of clinical-size tissue-engineered grafts. For example, vascular endothelial growth factor (VEGF is the master regulator of physiological blood vessel growth and is one of the main molecular targets of therapeutic angiogenesis approaches. However, angiogenesis is a complex process and there is a need to develop rational therapeutic strategies based on a firm understanding of basic vascular biology principles, as evidenced by the disappointing results of initial clinical trials of angiogenic factor delivery. In particular, the spatial localization of angiogenic signals in the extracellular matrix is crucial to ensure the proper assembly and maturation of new vascular structures. Here we discuss the therapeutic implications of matrix interactions of angiogenic factors, with a special emphasis on VEGF, as well as provide an overview of current approaches, based on protein and biomaterial engineering that mimic the regulatory functions of extracellular matrix to optimize the signaling microenvironment of vascular growth factors.

  12. Mathematical Model of Growth Factor Driven Haptotaxis and Proliferation in a Tissue Engineering Scaffold

    KAUST Repository

    Pohlmeyer, J. V.

    2013-01-29

    Motivated by experimental work (Miller et al. in Biomaterials 27(10):2213-2221, 2006, 32(11):2775-2785, 2011) we investigate the effect of growth factor driven haptotaxis and proliferation in a perfusion tissue engineering bioreactor, in which nutrient-rich culture medium is perfused through a 2D porous scaffold impregnated with growth factor and seeded with cells. We model these processes on the timescale of cell proliferation, which typically is of the order of days. While a quantitative representation of these phenomena requires more experimental data than is yet available, qualitative agreement with preliminary experimental studies (Miller et al. in Biomaterials 27(10):2213-2221, 2006) is obtained, and appears promising. The ultimate goal of such modeling is to ascertain initial conditions (growth factor distribution, initial cell seeding, etc.) that will lead to a final desired outcome. © 2013 Society for Mathematical Biology.

  13. Engineering a growth factor embedded nanofiber matrix niche to promote vascularization for functional cardiac regeneration.

    Science.gov (United States)

    Lakshmanan, Rajesh; Kumaraswamy, Priyadharshini; Krishnan, Uma Maheswari; Sethuraman, Swaminathan

    2016-08-01

    The major loss of tissue extracellular matrix (ECM) after myocardial ischemia is a serious burden that gradually leads to heart failure. Due to lack of available treatment methods to restore the cardiac function, various research strategies have come up to treat the ischemic myocardium. However these have met with limited success due to the complexity of the cardiac tissue, which exhibits a nanofibrous collagenous matrix with spatio-temporal localization of a combination of growth factors. To mimic the topographical and chemical cues of the natural cardiac tissue, we have fabricated a growth factor embedded nanofibrous scaffold through electrospinning. In our previous work, we have reported a nanofibrous matrix made of PLCL and PEOz with an average diameter of 500 nm. The scaffold properties were specifically characterized in vitro for cardio-compatibility. In the present study, we have loaded dual growth factors VEGF and bFGF in the nanofiber matrix and investigated its suitability for cardiac tissue engineering. The encapsulation and release of dual growth factors from the matrix were studied using XPS and ELISA. Bioactivity of the loaded growth factors towards proliferation and migration of endothelial cells (HUVECs) was evaluated through MTS and Boyden chamber assays respectively. The efficiency of growth factors on the nanofibrous matrix to activate signaling molecules was studied in HUVECs through gene expression analysis. Preclinical evaluation of the growth factor embedded nanofibrous patch in a rabbit acute myocardial infarction (AMI) model was studied and cardiac function assessment was made through ECG and echocardiography. The evidence for angiogenesis in the patch secured regions was analyzed through histopathology and immunohistochemistry. Our results confirm the effectiveness of growth factor embedded nanofiber matrix in restoration of cardiac function after ischemia when compared to conventional patch material thereby exhibiting promise as a

  14. Carbon nanotubes instruct physiological growth and functionally mature syncytia: nongenetic engineering of cardiac myocytes.

    Science.gov (United States)

    Martinelli, Valentina; Cellot, Giada; Toma, Francesca Maria; Long, Carlin S; Caldwell, John H; Zentilin, Lorena; Giacca, Mauro; Turco, Antonio; Prato, Maurizio; Ballerini, Laura; Mestroni, Luisa

    2013-07-23

    Myocardial tissue engineering currently represents one of the most realistic strategies for cardiac repair. We have recently discovered the ability of carbon nanotube scaffolds to promote cell division and maturation in cardiomyocytes. Here, we test the hypothesis that carbon nanotube scaffolds promote cardiomyocyte growth and maturation by altering the gene expression program, implementing the cell electrophysiological properties and improving networking and maturation of functional syncytia. In our study, we combine microscopy, biological and electrophysiological methodologies, and calcium imaging, to verify whether neonatal rat ventricular myocytes cultured on substrates of multiwall carbon nanotubes acquire a physiologically more mature phenotype compared to control (gelatin). We show that the carbon nanotube substrate stimulates the induction of a gene expression profile characteristic of terminal differentiation and physiological growth, with a 2-fold increase of α-myosin heavy chain (P carbon nanotubes appear to exert a protective effect against the pathologic stimulus of phenylephrine. Finally, cardiomyocytes on carbon nanotubes demonstrate a more mature electrophysiological phenotype of syncytia and intracellular calcium signaling. Thus, carbon nanotubes interacting with cardiomyocytes have the ability to promote physiological growth and functional maturation. These properties are unique in the current vexing field of tissue engineering, and offer unprecedented perspectives in the development of innovative therapies for cardiac repair.

  15. The interplay between tissue growth and scaffold degradation in engineered tissue constructs

    KAUST Repository

    O’Dea, R. D.

    2012-09-18

    In vitro tissue engineering is emerging as a potential tool to meet the high demand for replacement tissue, caused by the increased incidence of tissue degeneration and damage. A key challenge in this field is ensuring that the mechanical properties of the engineered tissue are appropriate for the in vivo environment. Achieving this goal will require detailed understanding of the interplay between cell proliferation, extracellular matrix (ECM) deposition and scaffold degradation. In this paper, we use a mathematical model (based upon a multiphase continuum framework) to investigate the interplay between tissue growth and scaffold degradation during tissue construct evolution in vitro. Our model accommodates a cell population and culture medium, modelled as viscous fluids, together with a porous scaffold and ECM deposited by the cells, represented as rigid porous materials. We focus on tissue growth within a perfusion bioreactor system, and investigate how the predicted tissue composition is altered under the influence of (1) differential interactions between cells and the supporting scaffold and their associated ECM, (2) scaffold degradation, and (3) mechanotransduction-regulated cell proliferation and ECM deposition. Numerical simulation of the model equations reveals that scaffold heterogeneity typical of that obtained from μCT scans of tissue engineering scaffolds can lead to significant variation in the flow-induced mechanical stimuli experienced by cells seeded in the scaffold. This leads to strong heterogeneity in the deposition of ECM. Furthermore, preferential adherence of cells to the ECM in favour of the artificial scaffold appears to have no significant influence on the eventual construct composition; adherence of cells to these supporting structures does, however, lead to cell and ECM distributions which mimic and exaggerate the heterogeneity of the underlying scaffold. Such phenomena have important ramifications for the mechanical integrity of

  16. Growth factor stimulation improves the structure and properties of scaffold-free engineered auricular cartilage constructs.

    Directory of Open Access Journals (Sweden)

    Renata G Rosa

    Full Text Available The reconstruction of the external ear to correct congenital deformities or repair following trauma remains a significant challenge in reconstructive surgery. Previously, we have developed a novel approach to create scaffold-free, tissue engineering elastic cartilage constructs directly from a small population of donor cells. Although the developed constructs appeared to adopt the structural appearance of native auricular cartilage, the constructs displayed limited expression and poor localization of elastin. In the present study, the effect of growth factor supplementation (insulin, IGF-1, or TGF-β1 was investigated to stimulate elastogenesis as well as to improve overall tissue formation. Using rabbit auricular chondrocytes, bioreactor-cultivated constructs supplemented with either insulin or IGF-1 displayed increased deposition of cartilaginous ECM, improved mechanical properties, and thicknesses comparable to native auricular cartilage after 4 weeks of growth. Similarly, growth factor supplementation resulted in increased expression and improved localization of elastin, primarily restricted within the cartilaginous region of the tissue construct. Additional studies were conducted to determine whether scaffold-free engineered auricular cartilage constructs could be developed in the 3D shape of the external ear. Isolated auricular chondrocytes were grown in rapid-prototyped tissue culture molds with additional insulin or IGF-1 supplementation during bioreactor cultivation. Using this approach, the developed tissue constructs were flexible and had a 3D shape in very good agreement to the culture mold (average error <400 µm. While scaffold-free, engineered auricular cartilage constructs can be created with both the appropriate tissue structure and 3D shape of the external ear, future studies will be aimed assessing potential changes in construct shape and properties after subcutaneous implantation.

  17. An Engineered Arginase FC Protein Inhibits Tumor Growth In Vitro and In Vivo

    Directory of Open Access Journals (Sweden)

    Lihua Li

    2013-01-01

    Full Text Available Arginine is a semiessential amino acid required for the growth of melanoma and hepatocellular carcinoma, and the enzymatic removal of arginine by pegylated arginine deiminase (ADI or arginase is being tested clinically. Here, we report a genetically engineered arginase FC fusion protein exhibiting a prolonged half-life and enhanced efficacy. The use of this enzyme to treat different tumor lines both inhibited cell proliferation and impaired cellular migration in vitro and in vivo. Our data reinforce the hypothesis that nutritional depletion is a key strategy for cancer treatment.

  18. Effect of Compressibility on Contrail Ice Particle Growth in an Engine Jet

    Science.gov (United States)

    Garnier, François; Maglaras, Ephi; Morency, François; Vancassel, Xavier

    2014-06-01

    In order to understand the formation process of condensation trails (contrails), the flow in the near field of an aircraft engine jet is studied by using the three-dimensional Large Eddy Simulation technique. The configuration consists of a hot round jet laden with soot particles. The particles are tracked using the Lagrangian approach, and their growth is calculated by a microphysics water vapour deposition model. A series of simulations are performed at a realistic Reynolds number (Re = 3.2 · 106) for two different jet Mach numbers: quasi-incompressible jet flow (M = 0.2) and compressible jet flow (M = 1). Whatever the Mach number used the ice crystals first appear at the edges of the jet where the hot and moist flow mixes with the cold and dry ambient air. Both the thermal transfers and the mass coupling, which are more significant for the quasi-incompressible jet flow, control the growth process.

  19. Human serum provided additional values in growth factors supplemented medium for human chondrocytes monolayer expansion and engineered cartilage construction.

    Science.gov (United States)

    Chua, K H; Aminuddin, B S; Fuzina, N H; Ruszymah, B H I

    2004-05-01

    We have previously formulated an optimized human chondrocytes growth medium based on 2% fetal bovine serum supplementation. For clinical usage, the animal serum must be replaced by patient own serum. We investigated the effects of human serum concentration for human nasal septum chondrocytes monolayer culture and cartilage reconstruction. Human serum demonstrated a dose dependent manner in promoting chondrocytes growth and cartilage engineering.

  20. A nanoparticulate injectable hydrogel as a tissue engineering scaffold for multiple growth factor delivery for bone regeneration

    Directory of Open Access Journals (Sweden)

    Dyondi D

    2012-12-01

    Full Text Available Deepti Dyondi,1 Thomas J Webster,2 Rinti Banerjee11Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India; 2Nanomedicine Laboratories, Division of Engineering and Department of Orthopedics, Brown University, Providence, RI, USAAbstract: Gellan xanthan gels have been shown to be excellent carriers for growth factors and as matrices for several tissue engineering applications. Gellan xanthan gels along with chitosan nanoparticles of 297 ± 61 nm diameter, basic fibroblast growth factor (bFGF, and bone morphogenetic protein 7 (BMP7 were employed in a dual growth factor delivery system to promote the differentiation of human fetal osteoblasts. An injectable system with ionic and temperature gelation was optimized and characterized. The nanoparticle loaded gels showed significantly improved cell proliferation and differentiation due to the sustained release of growth factors. A differentiation marker study was conducted, analyzed, and compared to understand the effect of single vs dual growth factors and free vs encapsulated growth factors. Dual growth factor loaded gels showed a higher alkaline phosphatase and calcium deposition compared to single growth factor loaded gels. The results suggest that encapsulation and stabilization of growth factors within nanoparticles and gels are promising for bone regeneration. Gellan xanthan gels also showed antibacterial effects against Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis, the common pathogens in implant failure.Keywords: bone tissue engineering, bone morphogenetic protein 7 (BMP7, basic fibroblast growth factor (bFGF, hydrogel, nanoparticles, osteoblasts

  1. Resetting the Growth Engines of the BRICS Countries as a Reaction to the Global Crisis

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    Iulia Monica Oehler-Șincai

    2013-01-01

    up exports and FDI as engines of economic growth, the administrative bodies at macro and microeconomic levels understood that the internal demand represents a complementary source of growth. In contrast with the most developed countries, which intensely resorted to austerity measures, the BRICS were able to adopt stimulus measures. Such Keynesian moves were possible, as the emerging countries entered the global crisis with strong macroeconomic and financial positions. As a matter of fact, the world financial and economic crisis erupted in a moment considered by the international experts as the “most prosperous” for these countries. The general measures adopted in order to stimulate the economy in the field of fiscal policy and monetary policy were combined with specific, sectoral ones. Such measures managed even to attenuate the negative effects of the global crisis at social level. Infrastructure development though public investment projects is used by the BRICS governments as one of the principal means to stimulate economic growth and jobs creation. Our paper concludes that, for the BRICS countries, the classical engines for economic growth like exports and inward FDI are complemented by additional growth engines: internal demand (spurred by the high level of remittances from abroad, the outward FDI, innovation and infrastructure development.

  2. Stem cells and biopharmaceuticals: vital roles in the growth of tissue-engineered small intestine.

    Science.gov (United States)

    Belchior, Gustavo Gross; Sogayar, Mari Cleide; Grikscheit, Tracy Cannon

    2014-06-01

    Tissue engineering currently constitutes a complex, multidisciplinary field exploring ideal sources of cells in combination with scaffolds or delivery systems in order to form a new, functional organ to replace native organ lack or loss. Short bowel syndrome (SBS) is a life-threatening condition with high morbidity and mortality rates in children. Current therapeutic strategies consist of costly and risky allotransplants that demand lifelong immunosuppression. A promising alternative is the implantation of autologous organoid units (OU) to create a tissue-engineered small intestine (TESI). This strategy is proven to be stem cell and mesenchyme dependent. Intestinal stem cells (ISCs) are located at the base of the crypt and are responsible for repopulating the cycling mucosa up to the villus tip. The stem cell niche governs the biology of ISCs and, together with the rest of the epithelium, communicates with the underlying mesenchyme to sustain intestinal homeostasis. Biopharmaceuticals are broadly used in the clinic to activate or enhance known signaling pathways and may greatly contribute to the development of a full-thickness intestine by increasing mucosal surface area, improving blood supply, and determining stem cell fate. This review will focus on tissue engineering as a means of building the new small intestine, highlighting the importance of stem cells and recombinant peptide growth factors as biopharmaceuticals.

  3. (*) Central Growth Factor Loaded Depots in Bone Tissue Engineering Scaffolds for Enhanced Cell Attraction.

    Science.gov (United States)

    Quade, Mandy; Knaack, Sven; Akkineni, Ashwini Rahul; Gabrielyan, Anastasia; Lode, Anja; Rösen-Wolff, Angela; Gelinsky, Michael

    2017-08-01

    Tissue engineering, the application of stem and progenitor cells in combination with an engineered extracellular matrix, is a promising strategy for bone regeneration. However, its success is limited by the lack of vascularization after implantation. The concept of in situ tissue engineering envisages the recruitment of cells necessary for tissue regeneration from the host environment foregoing ex vivo cell seeding of the scaffold. In this study, we developed a novel scaffold system for enhanced cell attraction, which is based on biomimetic mineralized collagen scaffolds equipped with a central biopolymer depot loaded with chemotactic agents. In humid milieu, as after implantation, the signaling factors are expected to slowly diffuse out of the central depot forming a gradient that stimulates directed cell migration toward the scaffold center. Heparin, hyaluronic acid, and alginate have been shown to be capable of depot formation. By using vascular endothelial growth factor (VEGF) as model factor, it was demonstrated that the release kinetics can be adjusted by varying the depot composition. While alginate and hyaluronic acid are able to reduce the initial burst and prolong the release of VEGF, the addition of heparin led to a much stronger retention that resulted in an almost linear release over 28 days. The biological activity of released VEGF was proven for all variants using an endothelial cell proliferation assay. Furthermore, migration experiments with endothelial cells revealed a relationship between the degree of VEGF retention and migration distance: cells invaded deepest in scaffolds containing a heparin-based depot indicating that the formation of a steep gradient is crucial for cell attraction. In conclusion, this novel in situ tissue engineering approach, specifically designed to recruit and accommodate endogenous cells upon implantation, appeared highly promising to stimulate cell invasion, which in turn would promote vascularization and finally new

  4. Evaluation of corneal cell growth on tissue engineering materials as artificial cornea scaffolds

    Directory of Open Access Journals (Sweden)

    Hai-Yan Wang

    2013-12-01

    Full Text Available The keratoprosthesis (KPro; artificial cornea is a special refractive device to replace human cornea by using heterogeneous forming materials for the implantation into the damaged eyes in order to obtain a certain vision. The main problems of artificial cornea are the biocompatibility and stability of the tissue particularly in penetrating keratoplasty. The current studies of tissue-engineered scaffold materials through comprising composites of natural and synthetic biopolymers together have developed a new way to artificial cornea. Although a wide agreement that the long-term stability of these devices would be greatly improved by the presence of cornea cells, modification of keratoprosthesis to support cornea cells remains elusive. Most of the studies on corneal substrate materials and surface modification of composites have tried to improve the growth and biocompatibility of cornea cells which can not only reduce the stimulus of heterogeneous materials, but also more importantly continuous and stable cornea cells can prevent the destruction of collagenase. The necrosis of stroma and spontaneous extrusion of the device, allow for maintenance of a precorneal tear layer, and play the role of ensuring a good optical surface and resisting bacterial infection. As a result, improvement in corneal cells has been the main aim of several recent investigations; some effort has focused on biomaterial for its well biological properties such as promoting the growth of cornea cells. The purpose of this review is to summary the growth status of the corneal cells after the implantation of several artificial corneas.

  5. Engineering the Activity and Lifetime of Heterogeneous Catalysts for Carbon Nanotube Growth via Substrate Ion Beam Bombardment (Postprint)

    Science.gov (United States)

    2014-07-31

    11,25 and chirality.19,20 CNTs are grown via heterogeneous catalysis using a thin film of catalyst on a wide variety of catalyst supports. Films of...another method in catalysis science to engineer supports to enhance both catalytic activity and lifetime with general implications for heterogeneous ...AFRL-RX-WP-JA-2014-0159 ENGINEERING THE ACTIVITY AND LIFETIME OF HETEROGENEOUS CATALYSTS FOR CARBON NANOTUBE GROWTH VIA SUBSTRATE ION BEAM

  6. 76 FR 38155 - California State Nonroad Engine Pollution Control Standards; Ocean-Going Vessels At-Berth in...

    Science.gov (United States)

    2011-06-29

    ... Regulation is designed to reduce emissions of oxides of nitrogen and particulate matter from auxiliary diesel... restricted by statute. EPA's Office of Transportation and Air Quality also maintains a webpage that contains... California ports (``At-Berth Regulation'').\\1\\ The At-Berth Regulation is designed to significantly...

  7. 78 FR 31536 - California State Nonroad Engine Pollution Control Standards; In-Use Heavy Duty Vehicles (as...

    Science.gov (United States)

    2013-05-24

    ... Diesel Particulate Matter, Oxides of Nitrogen and Other Criteria Pollutants from In-Use Heavy-Duty Diesel... motor vehicles which are not the subject of this decision (such regulations are not preempted under the... subsection in the context of section 209(b) motor vehicle waivers).\\8\\ \\6\\ 59 FR 36969 (July 20, 1994)....

  8. 77 FR 50502 - California State Nonroad Engine Pollution Control Standards; In-Use Heavy-Duty Vehicles (As...

    Science.gov (United States)

    2012-08-21

    ... the comment that is placed in the public docket and made available on the Internet. If you submit an... July 20, 1994, EPA promulgated a rule that sets forth, among other things, regulations providing the... 13, California Code of Regulations, section 2025. \\6\\ The definition of yard truck is at section 2025...

  9. THE POTENTIAL OF FEMALE ENTREPRENEURSHIP AS A REGIONAL GROWTH AND DEVELOPMENT ENGINE IN THE WESTERN ROMANIA

    Directory of Open Access Journals (Sweden)

    Pop Cohut Ioana

    2011-07-01

    Full Text Available Starting from the objectives, activities, and the results of the empirical, quantitative, and qualitative research carried out in the AntrES project (AntrES - Project acronym "Entrepreneurship and Equal Opportunities. A new school for women entrepreneurship" – Antreprenoriatul şi egalitatea de şanse. Un nou model de şcoală antreprenorială pentru femei, during the two years of implementation, in the Western Romania referring to the new businesses start up; business development; the motivation and difficulties of female entrepreneurs and potentially enterprising women; of their perceptions regarding the need for entrepreneurship education, the role of female entrepreneurship promotion and the impact of the successful models on new businesses start up – this paper presents directions of action meant to emphasize and support the potential of the female entrepreneurship in Romania, as a regional growth and development engine.

  10. Engineering an Obligate Photoautotrophic Cyanobacterium to Utilize Glycerol for Growth and Chemical Production.

    Science.gov (United States)

    Kanno, Masahiro; Atsumi, Shota

    2017-01-20

    Cyanobacteria have attracted much attention as a means to directly recycle carbon dioxide into valuable chemicals that are currently produced from petroleum. However, the titers and productivities achieved are still far below the level required in industry. To make a more industrially applicable production scheme, glycerol, a byproduct of biodiesel production, can be used as an additional carbon source for photomixotrophic chemical production. Glycerol is an ideal candidate due to its availability and low cost. In this study, we found that a heterologous glycerol respiratory pathway enabled Synechococcus elongatus PCC 7942 to utilize extracellular glycerol. The engineered strain produced 761 mg/L of 2,3-butanediol in 48 h with a 290% increase over the control strain under continuous light conditions. Glycerol supplementation also allowed for continuous cell growth and 2,3-butanediol production in diurnal light conditions. These results highlight the potential of glycerol as an additional carbon source for photomixotrophic chemical production in cyanobacteria.

  11. Engineering the growth pattern and cell morphology for enhanced PHB production by Escherichia coli.

    Science.gov (United States)

    Wu, Hong; Chen, Jinchun; Chen, Guo-Qiang

    2016-12-01

    E. coli JM109∆envC∆nlpD deleted with genes envC and nlpD responsible for degrading peptidoglycan (PG) led to long filamentous cell shapes. When cell fission ring location genes minC and minD of Escherichia coli were deleted, E. coli JM109∆minCD changed the cell growth pattern from binary division to multiple fissions. Bacterial morphology can be further engineered by overexpressing sulA gene resulting in inhibition on FtsZ, thus generating very long cellular filaments. By overexpressing sulA in E. coli JM109∆envC∆nlpD and E. coli JM109∆minCD harboring poly(3-hydroxybutyrate) (PHB) synthesis operon phbCAB encoded in plasmid pBHR68, respectively, both engineered cells became long filaments and accumulated more PHB compared with the wild-type. Under same shake flask growth conditions, E. coli JM109∆minCD (pBHR68) overexpressing sulA grown in multiple fission pattern accumulated approximately 70 % PHB in 9 g/L cell dry mass (CDM), which was significantly higher than E. coli JM109∆envC∆nlpD and the wild type, that produced 7.6 g/L and 8 g/L CDM containing 64 % and 51 % PHB, respectively. Results demonstrated that a combination of the new division pattern with elongated shape of E. coli improved PHB production. This provided a new vision on the enhanced production of inclusion bodies.

  12. Muscle Tissue Engineering Using Gingival Mesenchymal Stem Cells Encapsulated in Alginate Hydrogels Containing Multiple Growth Factors.

    Science.gov (United States)

    Ansari, Sahar; Chen, Chider; Xu, Xingtian; Annabi, Nasim; Zadeh, Homayoun H; Wu, Benjamin M; Khademhosseini, Ali; Shi, Songtao; Moshaverinia, Alireza

    2016-06-01

    Repair and regeneration of muscle tissue following traumatic injuries or muscle diseases often presents a challenging clinical situation. If a significant amount of tissue is lost the native regenerative potential of skeletal muscle will not be able to grow to fill the defect site completely. Dental-derived mesenchymal stem cells (MSCs) in combination with appropriate scaffold material, present an advantageous alternative therapeutic option for muscle tissue engineering in comparison to current treatment modalities available. To date, there has been no report on application of gingival mesenchymal stem cells (GMSCs) in three-dimensional scaffolds for muscle tissue engineering. The objectives of the current study were to develop an injectable 3D RGD-coupled alginate scaffold with multiple growth factor delivery capacity for encapsulating GMSCs, and to evaluate the capacity of encapsulated GMSCs to differentiate into myogenic tissue in vitro and in vivo where encapsulated GMSCs were transplanted subcutaneously into immunocompromised mice. The results demonstrate that after 4 weeks of differentiation in vitro, GMSCs as well as the positive control human bone marrow mesenchymal stem cells (hBMMSCs) exhibited muscle cell-like morphology with high levels of mRNA expression for gene markers related to muscle regeneration (MyoD, Myf5, and MyoG) via qPCR measurement. Our quantitative PCR analyzes revealed that the stiffness of the RGD-coupled alginate regulates the myogenic differentiation of encapsulated GMSCs. Histological and immunohistochemical/fluorescence staining for protein markers specific for myogenic tissue confirmed muscle regeneration in subcutaneous transplantation in our in vivo animal model. GMSCs showed significantly greater capacity for myogenic regeneration in comparison to hBMMSCs (p engineering.

  13. Priming Dental Pulp Stem Cells With Fibroblast Growth Factor-2 Increases Angiogenesis of Implanted Tissue-Engineered Constructs Through Hepatocyte Growth Factor and Vascular Endothelial Growth Factor Secretion.

    Science.gov (United States)

    Gorin, Caroline; Rochefort, Gael Y; Bascetin, Rumeyza; Ying, Hanru; Lesieur, Julie; Sadoine, Jérémy; Beckouche, Nathan; Berndt, Sarah; Novais, Anita; Lesage, Matthieu; Hosten, Benoit; Vercellino, Laetitia; Merlet, Pascal; Le-Denmat, Dominique; Marchiol, Carmen; Letourneur, Didier; Nicoletti, Antonino; Vital, Sibylle Opsahl; Poliard, Anne; Salmon, Benjamin; Muller, Laurent; Chaussain, Catherine; Germain, Stéphane

    2016-03-01

    Tissue engineering strategies based on implanting cellularized biomaterials are promising therapeutic approaches for the reconstruction of large tissue defects. A major hurdle for the reliable establishment of such therapeutic approaches is the lack of rapid blood perfusion of the tissue construct to provide oxygen and nutrients. Numerous sources of mesenchymal stem cells (MSCs) displaying angiogenic potential have been characterized in the past years, including the adult dental pulp. Establishment of efficient strategies for improving angiogenesis in tissue constructs is nevertheless still an important challenge. Hypoxia was proposed as a priming treatment owing to its capacity to enhance the angiogenic potential of stem cells through vascular endothelial growth factor (VEGF) release. The present study aimed to characterize additional key factors regulating the angiogenic capacity of such MSCs, namely, dental pulp stem cells derived from deciduous teeth (SHED). We identified fibroblast growth factor-2 (FGF-2) as a potent inducer of the release of VEGF and hepatocyte growth factor (HGF) by SHED. We found that FGF-2 limited hypoxia-induced downregulation of HGF release. Using three-dimensional culture models of angiogenesis, we demonstrated that VEGF and HGF were both responsible for the high angiogenic potential of SHED through direct targeting of endothelial cells. In addition, FGF-2 treatment increased the fraction of Stro-1+/CD146+ progenitor cells. We then applied in vitro FGF-2 priming to SHED before encapsulation in hydrogels and in vivo subcutaneous implantation. Our results showed that FGF-2 priming is more efficient than hypoxia at increasing SHED-induced vascularization compared with nonprimed controls. Altogether, these data demonstrate that FGF-2 priming enhances the angiogenic potential of SHED through the secretion of both HGF and VEGF.

  14. Gelatin-based hydrogel for vascular endothelial growth factor release in peripheral nerve tissue engineering.

    Science.gov (United States)

    Gnavi, S; di Blasio, L; Tonda-Turo, C; Mancardi, A; Primo, L; Ciardelli, G; Gambarotta, G; Geuna, S; Perroteau, I

    2017-02-01

    Hydrogels are promising materials in regenerative medicine applications, due to their hydrophilicity, biocompatibility and capacity to release drugs and growth factors in a controlled manner. In this study, biocompatible and biodegradable hydrogels based on blends of natural polymers were used in in vitro and ex vivo experiments as a tool for VEGF-controlled release to accelerate the nerve regeneration process. Among different candidates, the angiogenic factor VEGF was selected, since angiogenesis has been long recognized as an important and necessary step during tissue repair. Recent studies have pointed out that VEGF has a beneficial effect on motor neuron survival and Schwann cell vitality and proliferation. Moreover, VEGF administration can sustain and enhance the growth of regenerating peripheral nerve fibres. The hydrogel preparation process was optimized to allow functional incorporation of VEGF, while preventing its degradation and denaturation. VEGF release was quantified through ELISA assay, whereas released VEGF bioactivity was validated in human umbilical vein endothelial cells (HUVECs) and in a Schwann cell line (RT4-D6P2T) by assessing VEGFR-2 and downstream effectors Akt and Erk1/2 phosphorylation. Moreover, dorsal root ganglia explants cultured on VEGF-releasing hydrogels displayed increased neurite outgrowth, providing confirmation that released VEGF maintained its effect, as also confirmed in a tubulogenesis assay. In conclusion, a gelatin-based hydrogel system for bioactive VEGF delivery was developed and characterized for its applicability in neural tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd. Copyright © 2014 John Wiley & Sons, Ltd.

  15. Implications of evolutionary engineering for growth and recombinant protein production in methanol-based growth media in the yeast Pichia pastoris.

    Science.gov (United States)

    Moser, Josef W; Prielhofer, Roland; Gerner, Samuel M; Graf, Alexandra B; Wilson, Iain B H; Mattanovich, Diethard; Dragosits, Martin

    2017-03-17

    Pichia pastoris is a widely used eukaryotic expression host for recombinant protein production. Adaptive laboratory evolution (ALE) has been applied in a wide range of studies in order to improve strains for biotechnological purposes. In this context, the impact of long-term carbon source adaptation in P. pastoris has not been addressed so far. Thus, we performed a pilot experiment in order to analyze the applicability and potential benefits of ALE towards improved growth and recombinant protein production in P. pastoris. Adaptation towards growth on methanol was performed in replicate cultures in rich and minimal growth medium for 250 generations. Increased growth rates on these growth media were observed at the population and single clone level. Evolved populations showed various degrees of growth advantages and trade-offs in non-evolutionary growth conditions. Genome resequencing revealed a wide variety of potential genetic targets associated with improved growth performance on methanol-based growth media. Alcohol oxidase represented a mutational hotspot since four out of seven evolved P. pastoris clones harbored mutations in this gene, resulting in decreased Aox activity, despite increased growth rates. Selected clones displayed strain-dependent variations for AOX-promoter based recombinant protein expression yield. One particularly interesting clone showed increased product titers ranging from a 2.5-fold increase in shake flask batch culture to a 1.8-fold increase during fed batch cultivation. Our data indicate a complex correlation of carbon source, growth context and recombinant protein production. While similar experiments have already shown their potential in other biotechnological areas where microbes were evolutionary engineered for improved stress resistance and growth, the current dataset encourages the analysis of the potential of ALE for improved protein production in P. pastoris on a broader scale.

  16. Latent Transforming Growth Factor-beta1 Functionalised Electrospun Scaffolds Promote Human Cartilage Differentiation: Towards an Engineered Cartilage Construct

    Directory of Open Access Journals (Sweden)

    Erh-Hsuin Lim

    2013-11-01

    Full Text Available BackgroundTo overcome the potential drawbacks of a short half-life and dose-related adverse effects of using active transforming growth factor-beta 1 for cartilage engineering, a cell-mediated latent growth factor activation strategy was developed incorporating latent transforming growth factor-β1 (LTGF into an electrospun poly(L-lactide scaffold.MethodsThe electrospun scaffold was surface modified with NH3 plasma and biofunctionalised with LTGF to produce both random and orientated biofunctionalised electrospun scaffolds. Scaffold surface chemical analysis and growth factor bioavailability assays were performed. In vitro biocompatibility and human nasal chondrocyte gene expression with these biofunctionalised electrospun scaffold templates were assessed. In vivo chondrogenic activity and chondrocyte gene expression were evaluated in athymic rats.ResultsChemical analysis demonstrated that LTGF anchored to the scaffolds was available for enzymatic, chemical and cell activation. The biofunctionalised scaffolds were non-toxic. Gene expression suggested chondrocyte re-differentiation after 14 days in culture. By 6 weeks, the implanted biofunctionalised scaffolds had induced highly passaged chondrocytes to re-express Col2A1 and produce type II collagen.ConclusionsWe have demonstrated a proof of concept for cell-mediated activation of anchored growth factors using a novel biofunctionalised scaffold in cartilage engineering. This presents a platform for development of protein delivery systems and for tissue engineering.

  17. Relaxor-based ferroelectric single crystals: growth, domain engineering, characterization and applications

    Science.gov (United States)

    Sun, Enwei; Cao, Wenwu

    2014-01-01

    In the past decade, domain engineered relaxor-PT ferroelectric single crystals, including (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-PT), (1-x)Pb(Zn1/3Nb2/3)O3-xPbTiO3 (PZN-PT) and (1-x-y)Pb(In1/2Nb1/2)O3-yPb(Mg1/3Nb2/3)O3-xPbTiO3 (PIN-PMN-PT), with compositions near the morphotropic phase boundary (MPB) have triggered a revolution in electromechanical devices owing to their giant piezoelectric properties and ultra-high electromechanical coupling factors. Compared to traditional PbZr1-xTixO3 (PZT) ceramics, the piezoelectric coefficient d33 is increased by a factor of 5 and the electromechanical coupling factor k33 is increased from 90%. Many emerging rich physical phenomena, such as charged domain walls, multi-phase coexistence, domain pattern symmetries, etc., have posed challenging fundamental questions for scientists. The superior electromechanical properties of these domain engineered single crystals have prompted the design of a new generation electromechanical devices, including sensors, transducers, actuators and other electromechanical devices, with greatly improved performance. It took less than 7 years from the discovery of larger size PMN-PT single crystals to the commercial production of the high-end ultrasonic imaging probe “PureWave”. The speed of development is unprecedented, and the research collaboration between academia and industrial engineers on this topic is truly intriguing. It is also exciting to see that these relaxor-PT single crystals are being used to replace traditional PZT piezoceramics in many new fields outside of medical imaging. The new ternary PIN-PMN-PT single crystals, particularly the ones with Mn-doping, have laid a solid foundation for innovations in high power acoustic projectors and ultrasonic motors, hinting another revolution in underwater SONARs and miniature actuation devices. This article intends to provide a comprehensive review on the development of relaxor-PT single crystals, spanning material discovery, crystal growth

  18. Relaxor-based ferroelectric single crystals: growth, domain engineering, characterization and applications.

    Science.gov (United States)

    Sun, Enwei; Cao, Wenwu

    2014-08-01

    In the past decade, domain engineered relaxor-PT ferroelectric single crystals, including (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-PT), (1-x)Pb(Zn1/3Nb2/3)O3-xPbTiO3 (PZN-PT) and (1-x-y)Pb(In1/2Nb1/2)O3-yPb(Mg1/3Nb2/3)O3-xPbTiO3 (PIN-PMN-PT), with compositions near the morphotropic phase boundary (MPB) have triggered a revolution in electromechanical devices owing to their giant piezoelectric properties and ultra-high electromechanical coupling factors. Compared to traditional PbZr1-x Ti x O3 (PZT) ceramics, the piezoelectric coefficient d33 is increased by a factor of 5 and the electromechanical coupling factor k33 is increased from 90%. Many emerging rich physical phenomena, such as charged domain walls, multi-phase coexistence, domain pattern symmetries, etc., have posed challenging fundamental questions for scientists. The superior electromechanical properties of these domain engineered single crystals have prompted the design of a new generation electromechanical devices, including sensors, transducers, actuators and other electromechanical devices, with greatly improved performance. It took less than 7 years from the discovery of larger size PMN-PT single crystals to the commercial production of the high-end ultrasonic imaging probe "PureWave". The speed of development is unprecedented, and the research collaboration between academia and industrial engineers on this topic is truly intriguing. It is also exciting to see that these relaxor-PT single crystals are being used to replace traditional PZT piezoceramics in many new fields outside of medical imaging. The new ternary PIN-PMN-PT single crystals, particularly the ones with Mn-doping, have laid a solid foundation for innovations in high power acoustic projectors and ultrasonic motors, hinting another revolution in underwater SONARs and miniature actuation devices. This article intends to provide a comprehensive review on the development of relaxor-PT single crystals, spanning material discovery, crystal growth

  19. Collagen-poly(dialdehyde) guar gum based porous 3D scaffolds immobilized with growth factor for tissue engineering applications.

    Science.gov (United States)

    Ragothaman, Murali; Palanisamy, Thanikaivelan; Kalirajan, Cheirmadurai

    2014-12-19

    Here we report the preparation of collagen-poly(dialdehyde) guar gum based hybrid functionalized scaffolds covalently immobilized with platelet derived growth factor - BB for tissue engineering applications. Poly(dialdehyde) guar gum was synthesized from selective oxidation of guar gum using sodium periodate. The synthesized poly(dialdehyde) guar gum not only promotes crosslinking of collagen but also immobilizes the platelet derived growth factor through imine bonds. The covalent crosslinking formed in collagen improves thermal, swelling and biodegradation properties of the hybrid scaffolds. The prepared hybrid scaffolds show 3D interconnected honeycomb porous structure when viewed under a microscope. The release of immobilized platelet derived growth factor was seen up to 13th day of incubation thereby proving its sustained delivery. The developed hybrid scaffold leads to a quantum increase in NIH 3T3 fibroblast cell density and proliferation thereby demonstrating its potential for tissue engineering applications.

  20. A novel methodology for non-linear system identification of battery cells used in non-road hybrid electric vehicles

    Science.gov (United States)

    Unger, Johannes; Hametner, Christoph; Jakubek, Stefan; Quasthoff, Marcus

    2014-12-01

    An accurate state of charge (SoC) estimation of a traction battery in hybrid electric non-road vehicles, which possess higher dynamics and power densities than on-road vehicles, requires a precise battery cell terminal voltage model. This paper presents a novel methodology for non-linear system identification of battery cells to obtain precise battery models. The methodology comprises the architecture of local model networks (LMN) and optimal model based design of experiments (DoE). Three main novelties are proposed: 1) Optimal model based DoE, which aims to high dynamically excite the battery cells at load ranges frequently used in operation. 2) The integration of corresponding inputs in the LMN to regard the non-linearities SoC, relaxation, hysteresis as well as temperature effects. 3) Enhancements to the local linear model tree (LOLIMOT) construction algorithm, to achieve a physical appropriate interpretation of the LMN. The framework is applicable for different battery cell chemistries and different temperatures, and is real time capable, which is shown on an industrial PC. The accuracy of the obtained non-linear battery model is demonstrated on cells with different chemistries and temperatures. The results show significant improvement due to optimal experiment design and integration of the battery non-linearities within the LMN structure.

  1. HTCC-Modified Nanoclay for Tissue Engineering Applications: A Synergistic Cell Growth and Antibacterial Efficiency

    Directory of Open Access Journals (Sweden)

    Majid Aliabadi

    2013-01-01

    Full Text Available This paper deals with the synthesis of a biocompatible chitosan ammonium salt N-(2-hydroxy propyl-3-trimethylammonium chitosan chloride (HTCC and using it in montmorillonite ion-exchange process. HTCC-modified montmorillonite (Mt with different chemical ratios was successfully synthesized, and their characteristics have been verified by XRD and FTIR analyses. Produced samples have been evaluated in terms of antibacterial efficiency and biocompatibility (cell culture test. Antibacterial efficiency of synthesized HTCC/Mt samples has been confirmed against both gram negative bacteria (Escherichia coli and gram positive bacteria (Staphylococcus aureus. The results disclosed that the antibacterial efficiency of HTCC-modified montmorillonite was unexpectedly even more than HTCC. This excellent synergistic effect has been referred to entrapping bacteria between the intercalated structures of HTCC-modified montmorillonite. Then HTCC on clay layers can seriously attack and damage the entrapped bacteria. An extraordinary biocompatibility, cell attachment, and cell growth even more than tissue culture polystyrene (TCPS have been recorded in the case of this novel kind of modified clay. Due to existing concerns about serious and chronic infections after implant placement, this natural-based bioactive and antibacterial modified clay can be used in electrospun nanofibers and other polymeric implants with promising mechanical properties for tissue engineering applications.

  2. HTCC-modified nanoclay for tissue engineering applications: a synergistic cell growth and antibacterial efficiency.

    Science.gov (United States)

    Aliabadi, Majid; Dastjerdi, Roya; Kabiri, Kourosh

    2013-01-01

    This paper deals with the synthesis of a biocompatible chitosan ammonium salt N-(2-hydroxy) propyl-3-trimethylammonium chitosan chloride (HTCC) and using it in montmorillonite ion-exchange process. HTCC-modified montmorillonite (Mt) with different chemical ratios was successfully synthesized, and their characteristics have been verified by XRD and FTIR analyses. Produced samples have been evaluated in terms of antibacterial efficiency and biocompatibility (cell culture test). Antibacterial efficiency of synthesized HTCC/Mt samples has been confirmed against both gram negative bacteria (Escherichia coli) and gram positive bacteria (Staphylococcus aureus). The results disclosed that the antibacterial efficiency of HTCC-modified montmorillonite was unexpectedly even more than HTCC. This excellent synergistic effect has been referred to entrapping bacteria between the intercalated structures of HTCC-modified montmorillonite. Then HTCC on clay layers can seriously attack and damage the entrapped bacteria. An extraordinary biocompatibility, cell attachment, and cell growth even more than tissue culture polystyrene (TCPS) have been recorded in the case of this novel kind of modified clay. Due to existing concerns about serious and chronic infections after implant placement, this natural-based bioactive and antibacterial modified clay can be used in electrospun nanofibers and other polymeric implants with promising mechanical properties for tissue engineering applications.

  3. Lipid engineering reveals regulatory roles for membrane fluidity in yeast flocculation and oxygen-limited growth

    Energy Technology Data Exchange (ETDEWEB)

    Degreif, Daniel [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Technical Univ. of Darmstadt (Germany); de Rond, Tristan [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Univ. of California, Berkeley, CA (United States); Bertl, Adam [Technical Univ. of Darmstadt (Germany); Keasling, Jay D. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Technical Univ. of Denmark, Lyngby (Denmark); Budin, Itay [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Univ. of California, Berkeley, CA (United States)

    2017-03-18

    Cells modulate lipid metabolism in order to maintain membrane homeostasis. In this paper, we use a metabolic engineering approach to manipulate the stoichiometry of fatty acid unsaturation, a regulator of cell membrane fluidity, in Saccharomyces cerevisiae. Unexpectedly, reduced lipid unsaturation triggered cell-cell adhesion (flocculation), a phenomenon characteristic of industrial yeast but uncommon in laboratory strains. We find that ER lipid saturation sensors induce expression of FLO1 – encoding a cell wall polysaccharide binding protein – independently of its canonical regulator. In wild-type cells, Flo1p-dependent flocculation occurs under oxygen-limited growth, which reduces unsaturated lipid synthesis and thus serves as the environmental trigger for flocculation. Transcriptional analysis shows that FLO1 is one of the most highly induced genes in response to changes in lipid unsaturation, and that the set of membrane fluidity-sensitive genes is globally activated as part of the cell's long-term response to hypoxia during fermentation. Finally, our results show how the lipid homeostasis machinery of budding yeast is adapted to carry out a broad response to an environmental stimulus important in biotechnology.

  4. A polymer nanoparticle with engineered affinity for a vascular endothelial growth factor (VEGF165)

    Science.gov (United States)

    Koide, Hiroyuki; Yoshimatsu, Keiichi; Hoshino, Yu; Lee, Shih-Hui; Okajima, Ai; Ariizumi, Saki; Narita, Yudai; Yonamine, Yusuke; Weisman, Adam C.; Nishimura, Yuri; Oku, Naoto; Miura, Yoshiko; Shea, Kenneth J.

    2017-07-01

    Protein affinity reagents are widely used in basic research, diagnostics and separations and for clinical applications, the most common of which are antibodies. However, they often suffer from high cost, and difficulties in their development, production and storage. Here we show that a synthetic polymer nanoparticle (NP) can be engineered to have many of the functions of a protein affinity reagent. Polymer NPs with nM affinity to a key vascular endothelial growth factor (VEGF165) inhibit binding of the signalling protein to its receptor VEGFR-2, preventing receptor phosphorylation and downstream VEGF165-dependent endothelial cell migration and invasion into the extracellular matrix. In addition, the NPs inhibit VEGF-mediated new blood vessel formation in Matrigel plugs in vivo. Importantly, the non-toxic NPs were not found to exhibit off-target activity. These results support the assertion that synthetic polymers offer a new paradigm in the search for abiotic protein affinity reagents by providing many of the functions of their protein counterparts.

  5. Enhanced boundary lubrication properties of engineered menisci by lubricin localization with insulin-like growth factor I treatment.

    Science.gov (United States)

    Bonnevie, Edward D; Puetzer, Jennifer L; Bonassar, Lawrence J

    2014-06-27

    In this study we analyzed the effects of IGF-I on the boundary lubricating ability of engineered meniscal tissue using a high density collagen gel seeded with meniscal fibrochondrocytes. Biochemical, histological, immunohistochemical, and tribological analyses were carried out to determine a construct's ability to functionally localize lubricin. Our study revealed that supplementation with IGF-I enhanced both the proliferation of cells within the construct as well as enhanced the anabolic activity of the seeded cells. Growth factor supplementation also facilitated the localization of ECM constituents (i.e. fibronectin and type II collagen) near the tissue surface that are important for the localization of lubricin, a boundary lubricant. Consequently, we found localized lubricin in the constructs supplemented with IGF-I. Tribologically, we demonstrated that lubricin serves as a boundary lubricant adsorbed to native meniscal surfaces. Lubricin removal from the native meniscus surface increased boundary friction coefficient by 40%. For the engineered constructs, the lubricin localization facilitated by growth factor supplementation also reduced friction coefficient by a similar margin, but similar results were not evident in control constructs. This study demonstrates that the use of growth factors in meniscal tissue engineering can enhance tribological properties by facilitating the localization of boundary lubricants at the surface of engineered tissue.

  6. ENSURING THE AVAILABILITY AND RELIABILITY OF UREA DOSING FOR ON-ROAD AND NON-ROAD

    Energy Technology Data Exchange (ETDEWEB)

    Barton, G; Lonsdale, B

    2003-08-24

    The purpose of this presentation is to address two important issues. The first issue is nationwide availability of urea. The second is assurance by the engine maker that the engine cannot operate without urea. In regard to the first issue, North American urea production can support SCR needs for the Heavy Duty truck industry. The existing distribution methods, pathways and technology could be utilized for urea supply with no new invention required. Urea usage and storage capacity on vehicles would support long distances between tank refills, as SCR could be initially rolled out with a limited infrastructure. The price of urea should be less than diesel fuel and urea SCR should have a fuel economy advantage over competing technologies. It can be in place by 2007. In regard to the second issue, sensor technology exists to monitor urea tank level and verify that the fluid in the tank is urea. NOx sensors are available to monitor tailpipe NOx, ensuring the entire SCR system is functioning properly, and inferring that urea is in the system. The monitoring system could be used to monitor compliance, record faults, and initiate enforcement actions as necessary. The monitoring system could initiate actions to encourage compliance.

  7. Engineering Assessment of TEG and TEG/FC Technology Growth Potential. Phase I. Engineering Assessment of Existing Thermoelectric Generator Technology.

    Science.gov (United States)

    1981-09-01

    heat pumps. Product Literature. File containing literature for: Global, Teledyne, and Melcor (thermoelectric coolers). 3M, Production Engineering...electrical power output is proportional to the heat input which is proportional to the temperature differential and the total surface area of the heated...efficiency (ratio of the useful heat to the heating value of the fuel input ). However, the catalytic combus- tion units operate at a temperature

  8. Molecular Tissue Engineering:Applications for Modulation of Mesenchymal Stem Cells Proliferation by Transforming Growth Factor

    Institute of Scientific and Technical Information of China (English)

    GUO; Xiaodong(

    2001-01-01

    [1]郭晓东 杜靖远 郑启新等.组织工程学技术修复关节软骨缺损研究进展.国外医学生物医学工程分册 2000 23(6):330[2]郭晓东 杜靖远 郑启新等.骨关节炎基因治疗进展.国外医学老年医学分册 2001 22(1):29[3]Grande D Breitbart A Mason J et al.Cartilage tissue engineering:current limitations and solutions.Clin Orthop 1999 367S:S176[4]Brittberg M Lindahl A Nilsson A et al.Treatment of deep cartilage defects in the knee with autologous chondrocyte transplantation.N Engl J Med 1994 331:889[5]Reddi A.Morphogenesis and tissue engineering of bone and cartilage:inductive signals stem cells and biomimetic biomaterials.Tissue Eng 2000 6(4) :351[6]Freed L Martin I Vunjak-Novakovic G.Frontiers in tissue engineering:in vitro modulation of chondrogene sis.Clin Orthop 1999 367S:S46[7]Evans C Ghivizzani S Smith P et al.Using gene therapy to protect and restore cartilage.Clin Orthop 2000 379 (Suppl) :S214[8]Fernandes J Martel-Pelletier J Pelletier J.Gene therapy for osteoarthritis:new perspectives for the twentyfirst century.Clin Orthop 2000 379(Suppl):S262[9]Mason J M Breitbart A S Barcia M et al.Cartilage and bone regeneration using gene-enhanced tissue engineering.Clin Orthop 2000 379 (Suppl):S171[10]郭晓东 杜靖远 郑启新等.分子生物学在组织工程学研究中的应用前景.中华实验外科杂志 2001 18(3):283[11]郭晓东 全大萍.组织工程与生物材料.见:生物医用材料导论.李世普主编.武汉:武汉工业大学出版社 2000.302[12]Liu Y Zheng Q X Du J Y et al.Cloning and expression of rat transforming growth factorβ1 cDNA in osteoblasts.J Tongji Med Univ 2000 20:63[13]Johnstone B Yoo J.Autologous mesenchymal progenitol cells in articular cartilage repair.Clin Orthop 1999 367S:S156[14]Yoo J Mandell I Angele P et al.Chondrogenitor cells and gene therapy.Clin Orthop 2000 379 (Suppl):S164[15]Caplan A I.Mesenchymal stem cells and gene

  9. History of the "Detector Materials Engineering" Crystal Growth Process for Bulk Hg1- x Cd x Te

    Science.gov (United States)

    Higgins, W. M.; Nelson, D. A.; Roy, R. G.; Murosako, R. P.; Lancaster, R. A.; Tower, J.; Norton, P.

    2013-11-01

    This paper reviews the history and technology of a bulk Hg1- x Cd x Te crystal growth process that was developed in the early 1980s at Honeywell Electro-Optics Division (presently BAE Systems, Electronic Solutions). The crystal growth process name, DME, was an acronym for the department name: Detector Materials Engineering. This was an accelerated crucible rotation technique (ACRT) vertical traveling heater method growth process. Crystal growth occurred in the pseudobinary Hg1- x Cd x Te system. ACRT mixing allowed the lower-density, higher- x-value Hg1- x Cd x Te growth nutrient in the upper region of the ampoule to replenish the depleted melt and allowed the growth of constant- x-value, higher-density Hg1- x Cd x Te. The material grown by this research and production growth process yielded single crystals that had improved purity, compositional uniformity, precipitate density, and reproducibility in comparison with solid-state recrystallization and other bulk Hg1- x Cd x Te growth techniques. Radial and longitudinal nonuniformities in x-value for Hg1- x Cd x Te were reduced to DME material had highly desired performance characteristics.

  10. Immunohistochemical detection of active transforming growth factor-beta in situ using engineered tissue

    Science.gov (United States)

    Barcellos-Hoff, M. H.; Ehrhart, E. J.; Kalia, M.; Jirtle, R.; Flanders, K.; Tsang, M. L.; Chatterjee, A. (Principal Investigator)

    1995-01-01

    The biological activity of transforming growth factor-beta 1 (TGF-beta) is governed by dissociation from its latent complex. Immunohistochemical discrimination of active and latent TGF-beta could provide insight into TGF-beta activation in physiological and pathological processes. However, evaluation of immunoreactivity specificity in situ has been hindered by the lack of tissue in which TGF-beta status is known. To provide in situ analysis of antibodies to differentiate between these functional forms, we used xenografts of human tumor cells modified by transfection to overexpress latent TGF-beta or constitutively active TGF-beta. This comparison revealed that, whereas most antibodies did not differentiate between TGF-beta activation status, the immunoreactivity of some antibodies was activation dependent. Two widely used peptide antibodies to the amino-terminus of TGF-beta, LC(1-30) and CC(1-30) showed marked preferential immunoreactivity with active TGF-beta versus latent TGF-beta in cryosections. However, in formalin-fixed, paraffin-embedded tissue, discrimination of active TGF-beta by CC(1-30) was lost and immunoreactivity was distinctly extracellular, as previously reported for this antibody. Similar processing-dependent extracellular localization was found with a neutralizing antibody raised to recombinant TGF-beta. Antigen retrieval recovered cell-associated immunoreactivity of both antibodies. Two antibodies to peptides 78-109 showed mild to moderate preferential immunoreactivity with active TGF-beta only in paraffin sections. LC(1-30) was the only antibody tested that discriminated active from latent TGF-beta in both frozen and paraffin-embedded tissue. Thus, in situ discrimination of active versus latent TGF-beta depends on both the antibody and tissue preparation. We propose that tissues engineered to express a specific form of a given protein provide a physiological setting in which to evaluate antibody reactivity with specific functional forms of a

  11. Tissue engineering of urethra using human vascular endothelial growth factor gene-modified bladder urothelial cells.

    Science.gov (United States)

    Guan, Yong; Ou, Lailiang; Hu, Gang; Wang, Hongjun; Xu, Yong; Chen, Jiatong; Zhang, Jun; Yu, Yaoting; Kong, Deling

    2008-02-01

    Acquired or congenital abnormalities may lead to urethral damage or loss, often requiring surgical reconstruction. Urethrocutaneous fistula and strictures are common complications, due to inadequate blood supply. Thus, adequate blood supply is a key factor for successful urethral tissue reconstruction. In this study, urethral grafts were prepared by seeding rabbit bladder urothelial cells (UCs) modified with human vascular endothelial growth factor (VEGF(165)) gene in the decellularized artery matrix. A retroviral pMSCV-VEGF(165)-GFP vector was cloned by insertion of VEGF open reading frame into the vector pMSCV-GFP (murine stem cell virus [MSCV]; green fluorescent protein [GFP]). Retrovirus was generated using package cell line 293T. Rabbit UCs were expanded ex vivo and modified with either MSCV-VEGF(165)-GFP or control MSCV-GFP retrovirus. Transduction efficiency was analyzed by fluorescence-activated cell sorting. The expression of VEGF(165) was examined by immunofluorescence, reverse transcript-polymerase chain reaction, Western blot, and enzyme-linked immunosorbent assay (ELISA). Decellularized rabbit artery matrix was seeded with genetically modified UCs and was subsequently cultured for 1 week prior to subcutaneous implantation into nude mice. Four weeks after implantation, the implants were harvested and analyzed by fluorescence microscopy, and by histologic and immunohistochemical staining. Ex vivo transduction efficiency of UCs was greater than 50% when concentrated retrovirus was used. The modified cells expressed both VEGF and GFP protein. Furthermore, the VEGF-modified UCs secreted VEGF in a time-dependent manner. Scanning electron microscopy and histochemical analysis of cross sections of the cultured urethral grafts showed that the seeded cells were attached and proliferated on the luminal surface of the decellularized artery matrix. In the subcutaneously implanted vessels, VEGF-modified cells significantly enhanced neovascularization and the

  12. [Micro/nano-engineering to control growth of neuronal cells and tissue engineering applied to the central nervous system].

    Science.gov (United States)

    Béduer, Amélie; Vaysse, Laurence; Loubinoux, Isabelle; Vieu, Christophe

    2013-01-01

    Central nervous system pathologies are often characterized by the loss of cell populations. A promising therapy now being developed consists in using bioactive materials, associating grafted cells to biopolymers which provide a scaffold for the in vitro building of new tissues, to be implanted in vivo. In the present article, the state of the art of this field, at crossroads between microtechnology and neuroscience, is described in detail; thereafter our own approach and results about interactions between adult human neural stem cells and microstructured polymers are summarized and discussed. In a second part, some central nervous system repair strategies, based on cerebral tissue engineering, are presented. We will report the main results of our studies to work out and characterize in vivo a cerebral bioprosthesis.

  13. Fe-SAPONITE and Chlorite Growth on Stainless Steel in Hydrothermal Engineered Barrier Experiments

    Science.gov (United States)

    Cheshire, M. C.; Caporuscio, F. A.; McCarney, M.

    2012-12-01

    The United States recently has initiated the Used Fuel Disposition campaign to evaluate various generic geological repositories for the disposal of high-level, spent nuclear fuel within environments ranging from hard-rock, salt/clay, to deep borehole settings. Previous work describing Engineered Barrier Systems (EBS) for repositories focused on low temperature and pressure conditions. The focus of this experimental work is to characterize the stability and alteration of a bentonite-based EBS with different waste container materials in brine at higher heat loads and pressures. All experiments were run at ~150 bar and 125 to 300 C for ~1 month. Unprocessed bentonite from Colony, Wyoming was used in the experiments as the clay buffer material. The redox conditions for each system were buffered along the magnetite-iron oxygen fugacity univariant curve using Fe3O4 and Feo filings. A K-Na-Ca-Cl-based salt solution was chosen to replicate deep groundwater compositions. The experimental mixtures were 1) salt solution-clay; 2) salt solution -clay-304 stainless steel; and 3) salt solution -clay-316 stainless steel with a water/bentonite ratio of ~9. Mineralogy and aqueous geochemistry of each experiment was evaluated to monitor the reactions that took place. No smectite illitization was observed in these reactions. However, it appears that K-smectite was produced, possibly providing a precursor to illitization. It is unclear whether reaction times were sufficient for bentonite illitization at 212 and 300 C or whether conditions conducive to illite formation were obtained. The more notable clay mineral reactions occurred at the stainless steel surfaces. Authigenic chlorite and Fe-saponite grew with their basal planes near perpendicular to the steel plate, forming a 10 - 40 μm thick 'corrosion' layer. Partial dissolution of the steel plates was the likely iron source for chlorite/saponite formation; however, dissolution of the Feo/Fe3O4 may also have acted as an iron source

  14. Accelerating proliferation of neural stem/progenitor cells in collagen sponges immobilized with engineered basic fibroblast growth factor for nervous system tissue engineering.

    Science.gov (United States)

    Ma, Fukai; Xiao, Zhifeng; Chen, Bing; Hou, Xianglin; Han, Jin; Zhao, Yannan; Dai, Jianwu; Xu, Ruxiang

    2014-03-10

    Neural stem/progenitor cells (NS/PCs) play a therapeutic role in nervous system diseases and contribute to functional recovery. However, their efficacy is limited as the majority of cells die post-transplantation. In this study, collagen sponges were utilized as carriers for NS/PCs. Basic fibroblast growth factor (bFGF), a mitogen for NS/PCs, was incorporated into the collagen sponges to stimulate NS/PC proliferation. However, the effect of native bFGF is limited because it diffuses into the culture medium and is lost following medium exchange. To overcome this problem, a collagen-binding polypeptide domain, which has high affinity to collagen, was fused with bFGF to sustain the exposure of NS/PCs within the collagen sponges to bFGF. The results indicated that the number of NS/PCs was significantly higher in collagen sponges incorporating engineered bFGF than in those with native bFGF or the PBS control after 7 days in culture. Here, we designed a natural biological neural scaffold consisting of collagen sponges, engineered bFGF, and NS/PCs. In addition to the effect of proliferated NS/PCs, the engineered bFGF retained in the natural biological neural scaffolds could have a direct effect on nervous system reconstruction. The two aspects of the natural biological neural scaffolds may produce synergistic effects, and so they represent a promising candidate for nervous system repair.

  15. Transforming growth factor-beta1 inhibits tissue engineering cartilage absorption via inducing the generation of regulatory T cells.

    Science.gov (United States)

    Li, Chichi; Bi, Wei; Gong, Yiming; Ding, Xiaojun; Guo, Xuehua; Sun, Jian; Cui, Lei; Yu, Youcheng

    2016-02-01

    The objective of the present study was to explore the mechanisms of transforming growth factor (TGF)-β1 inhibiting the absorption of tissue engineering cartilage. We transfected TGF-β1 gene into bone marrow mesenchymal stem cells (BMMSCs) and co-cultured with interferon (IFN)-γ and tumour necrosis factor (TNF)-α and CD4(+) CD25(-) T lymphocytes. We then characterized the morphological changes, apoptosis and characterization of chondrogenic-committed cells from TGF-β1(+) BMMSCs and explored their mechanisms. Results showed that BMMSCs apoptosis and tissue engineering cartilage absorption in the group with added IFN-γ and TNF-α were greater than in the control group. In contrast, there was little BMMSC apoptosis and absorption by tissue engineering cartilage in the group with added CD4(+) CD25(-) T lymphocytes; Foxp3(+) T cells and CD25(+) CD39(+) T cells were found. In contrast, no type II collagen or Foxp3(+) T cells or CD25(+) CD39(+) T cells was found in the TGF-β1(-) BMMSC group. The data suggest that IFN-γ and TNF-α induced BMMSCs apoptosis and absorption of tissue engineering cartilage, but the newborn regulatory T (Treg) cells inhibited the function of IFN-γ and TNF-α and protected BMMSCs and tissue engineering cartilage. TGF-β1not only played a cartilage inductive role, but also inhibited the absorption of tissue engineering cartilage. The pathway proposed in our study may simulate the actual reaction procedure after implantation of BMMSCs and tissue engineering cartilage in vivo. Copyright © 2013 John Wiley & Sons, Ltd.

  16. Simultaneous cell growth and ethanol production from cellulose by an engineered yeast consortium displaying a functional mini-cellulosome

    Directory of Open Access Journals (Sweden)

    Madan Bhawna

    2011-11-01

    Full Text Available Abstract Background The recalcitrant nature of cellulosic materials and the high cost of enzymes required for efficient hydrolysis are the major impeding steps to their practical usage for ethanol production. Ideally, a recombinant microorganism, possessing the capability to utilize cellulose for simultaneous growth and ethanol production, is of great interest. We have reported recently the use of a yeast consortium for the functional presentation of a mini-cellulosome structure onto the yeast surface by exploiting the specific interaction of different cohesin-dockerin pairs. In this study, we engineered a yeast consortium capable of displaying a functional mini-cellulosome for the simultaneous growth and ethanol production on phosphoric acid swollen cellulose (PASC. Results A yeast consortium composed of four different populations was engineered to display a functional mini-cellulosome containing an endoglucanase, an exoglucanase and a β-glucosidase. The resulting consortium was demonstrated to utilize PASC for growth and ethanol production. The final ethanol production of 1.25 g/L corresponded to 87% of the theoretical value and was 3-fold higher than a similar yeast consortium secreting only the three cellulases. Quantitative PCR was used to enumerate the dynamics of each individual yeast population for the two consortia. Results indicated that the slight difference in cell growth cannot explain the 3-fold increase in PASC hydrolysis and ethanol production. Instead, the substantial increase in ethanol production is consistent with the reported synergistic effect on cellulose hydrolysis using the displayed mini-cellulosome. Conclusions This report represents a significant step towards the goal of cellulosic ethanol production. This engineered yeast consortium displaying a functional mini-cellulosome demonstrated not only the ability to grow on the released sugars from PASC but also a 3-fold higher ethanol production than a similar yeast

  17. Lipid engineering reveals regulatory roles for membrane fluidity in yeast flocculation and oxygen-limited growth

    DEFF Research Database (Denmark)

    Degreif, Daniel; de Rond, Tristan; Bertl, Adam

    2017-01-01

    Cells modulate lipid metabolism in order to maintain membrane homeostasis. Here we use a metabolic engineering approach to manipulate the stoichiometry of fatty acid unsaturation, a regulator of cell membrane fluidity, in Saccharomyces cerevisiae. Unexpectedly, reduced lipid unsaturation triggere...

  18. Methods of monitoring cell fate and tissue growth in three-dimensional scaffold-based strategies for in vitro tissue engineering

    NARCIS (Netherlands)

    Leferink, Anne M.; Blitterswijk, van Clemens A.; Moroni, Lorenzo

    2016-01-01

    In the field of tissue engineering, there is a need for methods that allow assessing the performance of tissue-engineered constructs noninvasively in vitro and in vivo. To date, histological analysis is the golden standard to retrieve information on tissue growth, cellular distribution, and cell fat

  19. Novel magnetic fibrin hydrogel scaffolds containing thrombin and growth factors conjugated iron oxide nanoparticles for tissue engineering

    Directory of Open Access Journals (Sweden)

    Ziv-Polat O

    2012-03-01

    Full Text Available Ofra Ziv-Polat1, Hadas Skaat1, Abraham Shahar2, Shlomo Margel11Department of Chemistry, Bar-Ilan Institute of Nanotechnology and Advanced Materials, Ramat-Gan 52900, Israel; 2NVR Research Ltd, Nes-Ziona 74031, IsraelAbstract: Novel tissue-engineered magnetic fibrin hydrogel scaffolds were prepared by the interaction of thrombin-conjugated iron oxide magnetic nanoparticles with fibrinogen. In addition, stabilization of basal fibroblast growth factor (bFGF was achieved by the covalent and physical conjugation of the growth factor to the magnetic nanoparticles. Adult nasal olfactory mucosa (NOM cells were seeded in the transparent fibrin scaffolds in the absence or presence of the free or conjugated bFGF-iron oxide nanoparticles. The conjugated bFGF enhanced significantly the growth and differentiation of the NOM cells in the fibrin scaffolds, compared to the same or even five times higher concentration of the free bFGF. In the presence of the bFGF-conjugated magnetic nanoparticles, the cultured NOM cells proliferated and formed a three-dimensional interconnected network composed mainly of tapered bipolar cells. The magnetic properties of these matrices are due to the integration of the thrombin- and bFGF-conjugated magnetic nanoparticles within the scaffolds. The magnetic properties of these scaffolds may be used in future work for various applications, such as magnetic resonance visualization of the scaffolds after implantation and reloading the scaffolds via magnetic forces with bioactive agents, eg, growth factors bound to the iron oxide magnetic nanoparticles.Keywords: thrombin, fibroblast growth factor, fibrin scaffold, iron oxide nanoparticles, tissue engineering, magnetism, bioactive nanoparticle

  20. Tissue engineered bone using select growth factors: A comprehensive review of animal studies and clinical translation studies in man

    Directory of Open Access Journals (Sweden)

    D Gothard

    2014-10-01

    Full Text Available There is a growing socio-economic need for effective strategies to repair damaged bone resulting from disease, trauma and surgical intervention. Bone tissue engineering has received substantial investment over the last few decades as a result. A multitude of studies have sought to examine the efficacy of multiple growth factors, delivery systems and biomaterials within in vivo animal models for the repair of critical-sized bone defects. Defect repair requires recapitulation of in vivo signalling cascades, including osteogenesis, chondrogenesis and angiogenesis, in an orchestrated spatiotemporal manner. Strategies to drive parallel, synergistic and consecutive signalling of factors including BMP-2, BMP-7/OP-1, FGF, PDGF, PTH, PTHrP, TGF-β3, VEGF and Wnts have demonstrated improved bone healing within animal models. Enhanced bone repair has also been demonstrated in the clinic following European Medicines Agency and Food and Drug Administration approval of BMP-2, BMP-7/OP-1, PDGF, PTH and PTHrP. The current review assesses the in vivo and clinical data surrounding the application of growth factors for bone regeneration. This review has examined data published between 1965 and 2013. All bone tissue engineering studies investigating in vivo response of the growth factors listed above, or combinations thereof, utilising animal models or human trials were included. All studies were compiled from PubMed-NCBI using search terms including ‘growth factor name’, ‘in vivo’, ‘model/animal’, ‘human’, and ‘bone tissue engineering’. Focus is drawn to the in vivo success of osteoinductive growth factors incorporated within material implants both in animals and humans, and identifies the unmet challenges within the skeletal regenerative area.

  1. Controlled multiple growth factor delivery from bone tissue engineering scaffolds via designed affinity.

    Science.gov (United States)

    Suárez-González, Darilis; Lee, Jae Sung; Diggs, Alisha; Lu, Yan; Nemke, Brett; Markel, Mark; Hollister, Scott J; Murphy, William L

    2014-08-01

    It is known that angiogenesis plays an important role in bone regeneration and that release of angiogenic and osteogenic growth factors can enhance bone formation. Multiple growth factors play key roles in processes that lead to tissue formation/regeneration during natural tissue development and repair. Therefore, treatments aiming to mimic tissue regeneration can benefit from multiple growth factor release, and there remains a need for simple clinically relevant approaches for dual growth factor release. We hypothesized that mineral coatings could be used as a platform for controlled incorporation and release of multiple growth factors. Specifically, mineral-coated scaffolds were "dip coated" in multiple growth factor solutions, and growth factor binding and release were dictated by the growth factor-mineral binding affinity. Beta tricalcium phosphate (β-TCP) scaffolds were fabricated using indirect solid-free form fabrication techniques and coated with a thin conformal mineral layer. Mineral-coated β-TCP scaffolds were sequentially dipped in recombinant human vascular endothelial growth factor (rhVEGF) and a modular bone morphogenetic peptide, a mineral-binding version of bone morphogenetic protein 2 (BMP2), solutions to allow for the incorporation of each growth factor. The dual release profile showed sustained release of both growth factors for over more than 60 days. Scaffolds releasing either rhVEGF alone or the combination of growth factors showed an increase in blood vessel ingrowth in a dose-dependent manner in a sheep intramuscular implantation model. This approach demonstrates a "modular design" approach, in which a controllable biologics carrier is integrated into a structural scaffold as a thin surface coating.

  2. Protein engineering,expression,and activity of a novel fusion protein possessing keratinocyte growth factor 2 and fibronectin

    Institute of Scientific and Technical Information of China (English)

    Wonmo Kang; Junhyeog Jang

    2009-01-01

    Growth factor-induced proliferation and differentiation often require adhesion of cells to the extracellular matrix proteins such as fibronectin(FN).In this study,we aimed to investigate the effect of protein engineering of the keratinocyte growth factor 2(KGF2)fused to the FN on the mitogenic activity of KGF2.The fusion protein(KGF2-FN10),which was expressed in Escherichia coli,showed significantly enhanced mitogenic activity of KGF2 on human keratinocytes.Moreover,KGF2-FN10 fusion protein showed significantly increased activity to differentiate keratinocytes from native KGF2.In conclusion,these results suggest that KGF2-FN10 fusion protein has certain advantages over native KGF2 and may offer a novel strategy to potentiate the therapeutic effect of KGF2.

  3. A phenomenological model for mechanically mediated growth, remodeling, damage, and plasticity of gel-derived tissue engineered blood vessels.

    Science.gov (United States)

    Raykin, Julia; Rachev, Alexander I; Gleason, Rudolph L

    2009-10-01

    Mechanical stimulation has been shown to dramatically improve mechanical and functional properties of gel-derived tissue engineered blood vessels (TEBVs). Adjusting factors such as cell source, type of extracellular matrix, cross-linking, magnitude, frequency, and time course of mechanical stimuli (among many other factors) make interpretation of experimental results challenging. Interpretation of data from such multifactor experiments requires modeling. We present a modeling framework and simulations for mechanically mediated growth, remodeling, plasticity, and damage of gel-derived TEBVs that merge ideas from classical plasticity, volumetric growth, and continuum damage mechanics. Our results are compared with published data and suggest that this model framework can predict the evolution of geometry and material behavior under common experimental loading scenarios.

  4. Probing the Conformational and Functional Consequences of Disulfide Bond Engineering in Growth Hormone by Hydrogen-Deuterium Exchange Mass Spectrometry Coupled to Electron Transfer Dissociation

    DEFF Research Database (Denmark)

    Seger, Signe T; Breinholt, Jens; Faber, Johan H

    2015-01-01

    Human growth hormone (hGH), and its receptor interaction, is essential for cell growth. To stabilize a flexible loop between helices 3 and 4, while retaining affinity for the hGH receptor, we have engineered a new hGH variant (Q84C/Y143C). Here, we employ hydrogen-deuterium exchange mass spectrom...

  5. Controllable mineral coatings on scaffolds as carriers for growth factor release for bone tissue engineering

    Science.gov (United States)

    Saurez-Gonzalez, Darilis

    The work presented in this document, focused on the development and characterization of mineral coatings on scaffold materials to serve as templates for growth factor binding and release. Mineral coatings were formed using a biomimetic approach that consisted in the incubation of scaffolds in modified simulated body fluids (mSBF). To modulate the properties of the mineral coating, which we hypothesized would dictate growth factor release, we used carbonate (HCO3) concentration in mSBF of 4.2 mM, 25mM, and 100mM. Analysis of the mineral coatings formed using scanning electron microscopy indicated growth of a continuous layer of mineral with different morphologies. X-ray diffraction analysis showed peaks associated with hydroxyapatite. FTIR data confirmed the substitution of HCO3 in the mineral. As the extent of HCO3 substitution increased, the coating exhibited more rapid dissolution kinetics in an environment deficient in calcium and phosphate. The mineral coatings provided an effective mechanism for bioactive growth factor binding and release. Peptide versions of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP2) were bound with efficiencies up to 90% to mineral-coated PCL scaffolds. Recombinant human vascular endothelial growth factor (rhVEGF) also bound to mineral coated scaffolds with lower efficiency (20%) and released with faster release kinetics compared to peptides growth factor. Released rhVEGF induced human umbilical vein endothelial cell (HUVEC) proliferation in vitro and enhanced blood vessel formation in vivo in an intramuscular sheep model. In addition to the use the mineral coatings for single growth factor release, we expanded the concept and bound both an angiogenic (rhVEGF) and osteogenic (mBMP2) growth factor by a simple double dipping process. Sustained release of both growth factors was demonstrated for over 60 days. Released rhVEGF enhanced blood vessel formation in vivo in sheep and its biological activity was

  6. A generic strategy for pharmacological caging of growth factors for tissue engineering.

    Science.gov (United States)

    Karlsson, Maria; Lienemann, Philipp S; Sprossmann, Natallia; Heilmann, Katharina; Brummer, Tilman; Lutolf, Matthias P; Ehrbar, Martin; Weber, Wilfried

    2013-07-01

    The caging of small molecules has revolutionized biological research by providing a means to regulate a wide range of processes. Here we report on a generic pharmacological method to cage proteins in a similar fashion. The present approach is of value in both fundamental and applied research, e.g. in tissue engineering.

  7. Articular cartilage tissue engineering with plasma-rich in growth factors and stem cells with nano scaffolds

    Science.gov (United States)

    Montaser, Laila M.; Abbassy, Hadeer A.; Fawzy, Sherin M.

    2016-09-01

    The ability to heal soft tissue injuries and regenerate cartilage is the Holy Grail of musculoskeletal medicine. Articular cartilage repair and regeneration is considered to be largely intractable due to the poor regenerative properties of this tissue. Due to their low self-repair ability, cartilage defects that result from joint injury, aging, or osteoarthritis, are the most often irreversible and are a major cause of joint pain and chronic disability. However, current methods do not perfectly restore hyaline cartilage and may lead to the apparition of fibro- or continue hypertrophic cartilage. The lack of efficient modalities of treatment has prompted research into tissue engineering combining stem cells, scaffold materials and environmental factors. The field of articular cartilage tissue engineering, which aims to repair, regenerate, and/or improve injured or diseased cartilage functionality, has evoked intense interest and holds great potential for improving cartilage therapy. Plasma-rich in growth factors (PRGF) and/or stem cells may be effective for tissue repair as well as cartilage regenerative processes. There is a great promise to advance current cartilage therapies toward achieving a consistently successful approach for addressing cartilage afflictions. Tissue engineering may be the best way to reach this objective via the use of stem cells, novel biologically inspired scaffolds and, emerging nanotechnology. In this paper, current and emergent approach in the field of cartilage tissue engineering is presented for specific application. In the next years, the development of new strategies using stem cells, in scaffolds, with supplementation of culture medium could improve the quality of new formed cartilage.

  8. Small Angle X-ray Scattering Study of Palladium Nanoparticle Growth on Genetically Engineered Tobacco Mosaic Virus Nanotemplates

    Science.gov (United States)

    Manocchi, Amy K.

    Transition metal nanoparticles possess valuable specific size dependent properties that arise at the nanoscale, and differ significantly from their bulk properties. However, the fabrication of these nanoparticles is often difficult to predict and control due to harsh reaction conditions and effects of capping agents or surfactants. Therefore, there is a critical need for facile routes toward controllable nanoparticle fabrication. Biological supramolecules, such as viruses, offer attractive templates for nanoparticle synthesis, due to their precise size and shape. In addition, simple genetic modifications can be employed to confer additional functionality with a high number of precisely spaced functional groups. In this work we exploit the specificity of genetically modified Tobacco Mosaic Virus (TMV1cys) for readily controllable palladium (Pd) nanoparticle synthesis via simple electroless deposition. TMV1cys, engineered to display one cysteine residue on the surface of each of over 2000 identical coat proteins, provides high density precisely spaced thiol groups for the preferential nucleation and growth of Pd nanoparticles. Small-Angle X-ray Scattering (SAXS) was employed to provide a statistically meaningful route to the investigation of Pd nanoparticle size ranges formed on the viral-nanotemplates. Specifically, we examine the size range and thermal stability of Pd nanoparticles formed on surface assembled TMV1cys. Further, we investigate the growth of Pd nanoparticles on TMV1cys in solution using in situ SAXS to better understand and predict nanoparticle growth on these nanotemplates. Lastly, we compare TMV1cys templated particle growth to Pd nanoparticle growth in the absence of TMV1cys to elucidate the role of TMV in particle formation. We show that Pd nanoparticles form preferentially on surface assembled TMV1cys in high density in a broad particle size range (4-18nm). Further, we show that Pd nanoparticles are significantly smaller and more uniform when

  9. Insulin-like growth factor I enhances collagen synthesis in engineered human tendon tissue

    DEFF Research Database (Denmark)

    Herchenhan, Andreas; Bayer, Monika L.; Eliasson, Pernilla

    2015-01-01

    OBJECTIVE: Isolated human tendon cells form 3D tendon constructs that demonstrate collagen fibrillogenesis and feature structural similarities to tendon when cultured under tensile load. The exact role of circulating growth factors for collagen formation in tendon is sparsely examined. We...

  10. Interface engineering for oxide electronics: tuning electronic properties by atomically controlled growth

    NARCIS (Netherlands)

    Huijben, Mark

    2006-01-01

    The main aim of this thesis is to develop a controlled growth with atomic precision for the realization of artificial perovskite structures, to exploit the exceptional physical properties of complex oxide materials such as high-temperature superconductors and conducting interfaces between band

  11. Vocational Education and Training--An Engine for Economic Growth and a Vehicle for Social Inclusion?

    Science.gov (United States)

    Nilsson, Anders

    2010-01-01

    Vocational education and training (VET) has in recent years enjoyed a revival for two major reasons. Firstly, it is regarded as a suitable means of promoting economic growth. Secondly, it is seen as a potentially powerful tool for fostering social inclusion. In this review, these assumed effects are critically examined on the basis of the vastly…

  12. Fabrication and characterization of a novel microparticle with gyrus-patterned surface and growth factor delivery for cartilage tissue engineering

    Energy Technology Data Exchange (ETDEWEB)

    Huang Sha [Department of Oral Histology and Pathology, School of Stomatology, Fourth Military Medical University, Xi' an 710032 (China); Research and Development Center for Tissue Engineering, Fourth Military Medical University, Xi' an 710032 (China); Wang Yijuan [Key Laboratory for Macromolecular Science of Shaanxi Province, Shaanxi Normal University, Xi' an 710062 (China); Liang Tang [Department of Oral Histology and Pathology, School of Stomatology, Fourth Military Medical University, Xi' an 710032 (China); Research and Development Center for Tissue Engineering, Fourth Military Medical University, Xi' an 710032 (China); Jin Fang [Department of Orthodontics, School of Stomatology, Fourth Military Medical University, Xi' an 710032 (China); Liu Shouxin [Key Laboratory for Macromolecular Science of Shaanxi Province, Shaanxi Normal University, Xi' an 710062 (China); Jin Yan, E-mail: yanjin@fmmu.edu.cn [Department of Oral Histology and Pathology, School of Stomatology, Fourth Military Medical University, Xi' an 710032 (China); Research and Development Center for Tissue Engineering, Fourth Military Medical University, Xi' an 710032 (China)

    2009-05-05

    Microparticles can serve as substrates for cell amplification and deliver the expanded cells to the site of the defect. It was hypothesized that a novel microparticle combined of sustained and localized delivery of proliferative growth factors and gyrus-patterned surface would influence the cell behaviours of adherence and expansion on the microparticle in the present study. To test the hypothesis, gelatin particles with diameter ranging from 280 to 350 {mu}m were fabricated and were modified by cryogenic freeze-drying treatment and basic fibroblast growth factor (bFGF) incorporation. The results of in vitro chondrocyte culture illustrated that cells could proliferate more obviously on the microparticles with bFGF addition, but no correlation between attachment rate and bFGF was observed. On the other hand, microparticles with gyrus-patterned surface demonstrated the highest cell attachment rate and higher rate of cell growth, in particular on bFGF combined ones. It seems to be a promising candidate as a chondrocyte microparticle and could be the potential application in cartilage tissue engineering.

  13. Engineering of the redox imbalance of Fusarium oxysporum enables anaerobic growth on xylose

    DEFF Research Database (Denmark)

    Panagiotou, Gianni; Christakopoulos, Paul; Grotkjær, Thomas

    2006-01-01

    Dissimilatory nitrate reduction metabolism, of the natural xylose-fermenting fungus Fusarium oxysporum, was used as a strategy to achieve anaerobic growth and ethanol production from xylose. Beneficial alterations of the redox fluxes and thereby of the xylose metabolism were obtained by taking...... of nitrate with ammonium limited the growth significantly (0.15 g L-1 biomass). Using nitrate, the maximum acetate yield was 0.21 moles per mole of xylose and no xylitol excretion was observed. Furthermore, the network structure in the central carbon metabolism of F. oxysporum was characterized in steady...... state. F. oxysporum grew anaerobically on [1-C-13] labelled glucose and unlabelled xylose in chemostat cultivation with nitrate as nitrogen source. The use of labelled substrate allowed the precise determination of the glucose and xylose contribution to the carbon fluxes in the central metabolism...

  14. Selective growth and ordering of SiGe nanowires for band gap engineering.

    Science.gov (United States)

    Benkouider, A; Ronda, A; Gouyé, A; Herrier, C; Favre, L; Lockwood, D J; Rowell, N L; Delobbe, A; Sudraud, P; Berbezier, I

    2014-08-22

    Selective growth and self-organization of silicon-germanium (SiGe) nanowires (NWs) on focused ion beam (FIB) patterned Si(111) substrates is reported. In its first step, the process involves the selective synthesis of Au catalysts in SiO₂-free areas; its second step involves the preferential nucleation and growth of SiGe NWs on the catalysts. The selective synthesis process is based on a simple, room-temperature reduction of gold salts (Au³⁺Cl₄⁻) in aqueous solution, which provides well-organized Au catalysts. By optimizing the reduction process, we are able to generate a bidimensional regular array of Au catalysts with self-limited sizes positioned in SiO₂-free windows opened in a SiO₂/Si(111) substrate by FIB patterning. Such Au catalysts subsequently serve as preferential nucleation and growth sites of well-organized NWs. Furthermore, these NWs with tunable position and size exhibit the relevant features and bright luminescence that would find several applications in optoelectronic nanodevices.

  15. Engineering three-dimensional macroporous hydroxyethyl methacrylate-alginate-gelatin cryogel for growth and proliferation of lung epithelial cells.

    Science.gov (United States)

    Singh, Deepti; Zo, Sun Mi; Kumar, Ashok; Han, Sung Soo

    2013-01-01

    Three-dimensional (3D) growth of cell is of particular interest in the field of tissue engineering and regenerative medicine. Scaffolds used for this purpose are often tailor-made to mimic the microenvironment and the extracellular matrix of the tissue with defined role such as to provide appropriate structural, chemical, and mechanical support. The aim of the study was to design the macroporous matrix with potential in the field of tissue engineering especially for lung muscle regeneration. Blend of hydroxyethyl methacrylate-alginate-gelatin (HAG) cryogel scaffold was synthesized using cryogelation technique and this polymer material combination is being reported first time. The rheology study showed the elastic property of the material in wet state with no variation in storage modulus (G'), loss modulus (G″), and phase angle upon temperature variation. The microcomputer tomography (micro-CT) analysis confirmed the homogenous polymer structure with average pore diameter of 84 μm. Scaffold synthesized using polymer combinations which is mixture of polysaccharide (alginate) and protein (gelatin) provides supportive environment for human lung epithelial cell proliferation confirmed by cytoskeletal stain phalloidin and nuclei staining 4',6-diamidino-2-phenylindole checked for over three weeks. The in vivo biocompatibility was further performed which showed integration of scaffold to the surrounding tissue with ability to recruit cells. However, at first week, small amount of infiltrating mast cells were found which subsequently diminished in following weeks. Immunohistochemistry for dendritic cells confirmed in vivo biocompatible nature of the HAG scaffold. The mechanical strength, stiffness, elastic measurements, in vivo compatibility, and in vitro lung cell proliferation show the potentiality of HAG materials for lung tissue engineering.

  16. Urban Futures - Innovation Engines or Slums? A Stellar Evolution Model of Urban Growth

    Science.gov (United States)

    Shutters, S. T.; Timmes, F.; Desouza, K.

    2015-12-01

    Why, as cities grow in size and density, do some "ignite" into global engines of innovation and prosperity while others grow into dense slums? This is our overarching question as we explore a novel framework for thinking about the evolution of cities and, more specifically, the divergent trajectories they may take. We develop a speculative framework by examining the analogies between the evolution of cities and the evolution of stars. Like cities, stellar gas clouds can grow in mass, eventually reaching temperature and density thresholds at which they ignite the hydrogen fuel in their cores to become full-fledged stars. But not all gas and dust clouds share this fate. Some never achieve the critical conditions and do not unleash the energy we witness emanating from our own star. Some stars, after exhaustion of their initial fuel, evolve to incredible density but lack the temperature to ignite the next fuel needed to maintain the critical interactions that release so much energy. Instead they fade away to an object of intense density, but without the vibrant emission of light and energy associated with non-degenerate stars. The fate of cities, too, depends on the density of interactions - not of gas molecules, but of people. This elevated rate of face-to-face interactions in an urban core is critical for the transition to an innovative and creative economy. Yet, density is not enough, as evidenced both by many megacities in the developing world and degenerate stars. What is this missing element that, along with density, ignites a city and turns it into an innovation engine? With these analogies in mind, we explore whether they are useful for framing future research on cities, what questions they may help pose, and, more broadly, how physical, social, and natural scientists can all contribute to an interdisciplinary endeavor to understand cities more deeply.

  17. E-cadherin gene-engineered feeder systems for supporting undifferentiated growth of mouse embryonic stem cells.

    Science.gov (United States)

    Horie, Masanobu; Ito, Akira; Kiyohara, Takehiko; Kawabe, Yoshinori; Kamihira, Masamichi

    2010-11-01

    Conventionally, embryonic stem (ES) cells are cultured on a cell layer of mouse embryonic fibroblasts (MEFs) as feeder cells to support undifferentiated growth of ES cells. In this study, cell-cell interactions between mouse ES and feeder cells were artificially engineered via an epithelial cell adhesion molecule, E-cadherin, whose expression is considerable in ES cells. Mouse mesenchymal STO and NIH3T3 cells that were genetically engineered to express E-cadherin were used in ES cell cultures as feeder cells. ES cells cultured on the E-cadherin-expressing feeder cells maintained the expression of stem cell markers, alkaline phosphatase (AP), Oct3/4, Nanog and Sox2, and the efficiency of AP-positive colony formation was comparable to MEFs, and much better than parental STO and NIH3T3 cells. Furthermore, ES cells maintained on the E-cadherin-expressing feeder cells possessed the ability to differentiate into the three germ layers both in vitro and in vivo. The results indicated that E-cadherin expression in feeder cells could improve the performance of feeder cells, which may be further applicable to create new artificial feeder cell lines.

  18. Inhibition of tumor growth and metastasis by ATF-Fc, an engineered antibody targeting urokinase receptor.

    Science.gov (United States)

    Hu, Xian-Wen; Duan, Hai-Feng; Gao, Li-Hua; Pan, Shu-Yuan; Li, Yong-Mei; Xi, Yongyi; Zhao, Su-Rong; Yin, Liang; Li, Jin-Feng; Chen, Hui-Peng; Wu, Chu-Tse

    2008-05-01

    Urokinase (uPA) and its receptor (uPAR) play an important role in tumor growth and metastasis, and overexpression of these molecules is strongly correlated with poor prognosis in a variety of malignant tumors. In this study, ATF-Fc, an antibody-like molecule comprising the amino-terminal fragment of human uPA (ATF) linked to the Fc fragment of human IgG1 via a flexible linker was developed. Its antitumor activities were evaluated in vitro and in vivo. The results showed that ATF-Fc had obvious cytotoxic effect on several types of tumor cells, which is dependent on cellular expression of uPAR and its Fc fragment. Treatment with ATF-Fc caused a significant suppression on tumor growth and metastasis of xenograft human tumors (MCF-7 breast cancer and BGC-823 gastric cancer) in athymic nude mice. Furthermore, we demonstrated that ATF-Fc had an anti-angiogenesis activity both in vitro and in vivo. In conclusion, we provided a novel therapeutic antibody-like molecule in the management of a variety of solid tumors by disrupting the uPA/uPAR interaction.

  19. Attenuation of skeletal muscle wasting with recombinant human growth hormone secreted from a tissue-engineered bioartificial muscle

    Science.gov (United States)

    Vandenburgh, H.; Del Tatto, M.; Shansky, J.; Goldstein, L.; Russell, K.; Genes, N.; Chromiak, J.; Yamada, S.

    1998-01-01

    Skeletal muscle wasting is a significant problem in elderly and debilitated patients. Growth hormone (GH) is an anabolic growth factor for skeletal muscle but is difficult to deliver in a therapeutic manner by injection owing to its in vivo instability. A novel method is presented for the sustained secretion of recombinant human GH (rhGH) from genetically modified skeletal muscle implants, which reduces host muscle wasting. Proliferating murine C2C12 skeletal myoblasts stably transduced with the rhGH gene were tissue engineered in vitro into bioartificial muscles (C2-BAMs) containing organized postmitotic myofibers secreting 3-5 microg of rhGH/day in vitro. When implanted subcutaneously into syngeneic mice, C2-BAMs delivered a sustained physiologic dose of 2.5 to 11.3 ng of rhGH per milliliter of serum. rhGH synthesized and secreted by the myofibers was in the 22-kDa monomeric form and was biologically active, based on downregulation of a GH-sensitive protein synthesized in the liver. Skeletal muscle disuse atrophy was induced in mice by hindlimb unloading, causing the fast plantaris and slow soleus muscles to atrophy by 21 to 35% ( muscle-wasting disorders.

  20. Attenuation of skeletal muscle wasting with recombinant human growth hormone secreted from a tissue-engineered bioartificial muscle

    Science.gov (United States)

    Vandenburgh, H.; Del Tatto, M.; Shansky, J.; Goldstein, L.; Russell, K.; Genes, N.; Chromiak, J.; Yamada, S.

    1998-01-01

    Skeletal muscle wasting is a significant problem in elderly and debilitated patients. Growth hormone (GH) is an anabolic growth factor for skeletal muscle but is difficult to deliver in a therapeutic manner by injection owing to its in vivo instability. A novel method is presented for the sustained secretion of recombinant human GH (rhGH) from genetically modified skeletal muscle implants, which reduces host muscle wasting. Proliferating murine C2C12 skeletal myoblasts stably transduced with the rhGH gene were tissue engineered in vitro into bioartificial muscles (C2-BAMs) containing organized postmitotic myofibers secreting 3-5 microg of rhGH/day in vitro. When implanted subcutaneously into syngeneic mice, C2-BAMs delivered a sustained physiologic dose of 2.5 to 11.3 ng of rhGH per milliliter of serum. rhGH synthesized and secreted by the myofibers was in the 22-kDa monomeric form and was biologically active, based on downregulation of a GH-sensitive protein synthesized in the liver. Skeletal muscle disuse atrophy was induced in mice by hindlimb unloading, causing the fast plantaris and slow soleus muscles to atrophy by 21 to 35% ( muscle-wasting disorders.

  1. Redox engineering by ectopic expression of glutamate dehydrogenase genes links NADPH availability and NADH oxidation with cold growth in Saccharomyces cerevisiae

    OpenAIRE

    Ballester Tomás, Laura; Rández Gil, Francisca; Pérez Torrado, Roberto; Prieto Alamán, José Antonio

    2015-01-01

    Background Cold stress reduces microbial growth and metabolism being relevant in industrial processes like wine making and brewing. Knowledge on the cold transcriptional response of Saccharomyces cerevisiae suggests the need of a proper redox balance. Nevertheless, there are no direct evidence of the links between NAD(P) levels and cold growth and how engineering of enzymatic reactions requiring NAD(P) may be used to modify the performance of industrial strains at low temperature. Results Rec...

  2. Deciphering flux adjustments of engineered E. coli cells during fermentation with changing growth conditions

    DEFF Research Database (Denmark)

    He, Lian; Xiu, Yu; Jones, J. Andrew

    2017-01-01

    Microbial fermentation conditions are dynamic, due to transcriptional induction, nutrient consumption, or changes to incubation conditions. In this study, 13C-metabolic flux analysis was used to characterize two violacein-producing E. coli strains with vastly different productivities...... of the temporal metabolic changes in each stage, we performed 13C-MFA via isotopomer analysis of fast-turnover free metabolites. The results indicate strikingly stable flux ratios in the central metabolism throughout the early growth stages. In the late stages, however, the high producer rewired its flux......, and to profile their metabolic adjustments resulting from external perturbations during fermentation. The two strains were first grown at 37°C in stage 1, and then the temperature was transitioned to 20°C in stage 2 for the optimal expression of the violacein synthesis pathway. After induction, violacein...

  3. Deciphering flux adjustments of engineered E. coli cells during fermentation with changing growth conditions

    Energy Technology Data Exchange (ETDEWEB)

    He, Lian [Washington Univ., St. Louis, MO (United States); Xiu, Yu [Rensselaer Polytechnic Inst., Troy, NY (United States); Beijing Univ. of Chemical Technology (China); Jones, J. Andrew [Rensselaer Polytechnic Inst., Troy, NY (United States); Hamilton College, Clinton, NY (United States); Baidoo, Edward E. K. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Keasling, Jay D. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Technical Univ. of Denmark, Lyngby (Denmark); Tang, Yinjie J. [Washington Univ., St. Louis, MO (United States); Koffas, Mattheos A. G. [Rensselaer Polytechnic Inst., Troy, NY (United States)

    2016-12-23

    Microbial fermentation conditions are dynamic, due to transcriptional induction, nutrient consumption, or changes to incubation conditions. In this paper, 13C-metabolic flux analysis was used to characterize two violacein-producing E. coli strains with vastly different productivities, and to profile their metabolic adjustments resulting from external perturbations during fermentation. The two strains were first grown at 37 °C in stage 1, and then the temperature was transitioned to 20 °C in stage 2 for the optimal expression of the violacein synthesis pathway. After induction, violacein production was minimal in stage 3, but accelerated in stage 4 (early production phase) and 5 (late production phase) in the high producing strain, reaching a final concentration of 1.5 mmol/L. On the contrary, ~0.02 mmol/L of violacein was obtained from the low producing strain. To have a snapshot of the temporal metabolic changes in each stage, we performed 13C-MFA via isotopomer analysis of fast-turnover free metabolites. The results indicate strikingly stable flux ratios in the central metabolism throughout the early growth stages. In the late stages, however, the high producer rewired its flux distribution significantly, which featured an upregulated pentose phosphate pathway and TCA cycle, reflux from acetate utilization, negligible anabolic fluxes, and elevated maintenance loss, to compensate for nutrient depletion and drainage of some building blocks due to violacein overproduction. The low producer with stronger promoters shifted its relative fluxes in stage 5 by enhancing the flux through the TCA cycle and acetate overflow, while exhibiting a reduced biomass growth and a minimal flux towards violacein synthesis. Finally, interestingly, the addition of the violacein precursor (tryptophan) in the medium inhibited high producer but enhanced low producer's productivity, leading to hypotheses of unknown pathway regulations (such as metabolite

  4. Green fuels, growth engines after petroleum; Les carburants verts, moteurs de la croissance apres le petrole

    Energy Technology Data Exchange (ETDEWEB)

    Mili, Dino

    2010-09-15

    The contribution of the new fuels to a greener environment is important and immediate. Thanks to clean novel technologies and to commercial plant projects in development, companies like Enerkem contribute to satisfy increasing global demand for clean energy. They stimulate local economies by creating jobs in an industry that offers real growth potential. Green fuels will gradually allow us to let go of non sustainable energy sources like oil to adopt a way of life based on sustainable development. They will also allow a shift towards a green economy. [French] La contribution des nouveaux carburants a un environnement plus vert est importante et immediate. Grace a des technologies propres novatrices et a des projets d'sines commerciales en developpement, des entreprises comme Enerkem contribuent a satisfaire a la demande mondiale croissante en energie propre. Elles stimulent les economies locales par la creation d'emplois dans une industrie qui offre un veritable potentiel de croissance. Les carburants verts permettront graduellement de nous affranchir des sources d'energie non renouvelables comme le petrole pour adopter un mode de vie base sur le developpement durable. Ils permettront aussi un virage vers une economie verte.

  5. Open Innovation Projects in SMEs as an Engine for Sustainable Growth

    Directory of Open Access Journals (Sweden)

    Byungun Yoon

    2016-02-01

    Full Text Available Most innovation activities that are inevitable for sustainable growth are coordinated via research and development (R&D projects, which can differ widely in terms of both project and open innovation characteristics, even when conducted within the same firm. Therefore, it is important to consider the peculiarities of R&D projects when evaluating the performance of open innovation strategies, as well as to explore how the benefits and costs of open innovation are shaped by cross-level interactions. This study identifies the differences between successful and unsuccessful open innovation projects, in both firm-level and project-level terms. We focus on small and medium enterprises (SMEs, which usually lack the full set of internal resources and competences required to effectively develop, produce, and commercialize their innovations, and thus must adopt open innovation approaches more actively for sustainability. Adopting an empirical approach, we conducted a survey of 517 Korean SMEs and analyzed 241 successful and unsuccessful open innovation projects in depth. By combining measurements at the firm and project levels, this study provides new insight into the intra-organizational challenges of implementing open innovation projects, which are not only helpful to strategic decision-makers in SMEs, but also to those who make policies for them.

  6. Bioactive nanoengineered hydrogels for bone tissue engineering: a growth-factor-free approach.

    Science.gov (United States)

    Xavier, Janet R; Thakur, Teena; Desai, Prachi; Jaiswal, Manish K; Sears, Nick; Cosgriff-Hernandez, Elizabeth; Kaunas, Roland; Gaharwar, Akhilesh K

    2015-03-24

    Despite bone's impressive ability to heal after traumatic injuries and fractures, a significant need still exists for developing strategies to promote healing of nonunion defects. To address this issue, we developed collagen-based hydrogels containing two-dimensional nanosilicates. Nanosilicates are ultrathin nanomaterials with a high degree of anisotropy and functionality that results in enhanced surface interactions with biological entities compared to their respective three-dimensional counterparts. The addition of nanosilicates resulted in a 4-fold increase in compressive modulus along with an increase in pore size compared to collagen-based hydrogels. In vitro evaluation indicated that the nanocomposite hydrogels are capable of promoting osteogenesis in the absence of any osteoinductive factors. A 3-fold increase in alkaline phosphatase activity and a 4-fold increase in the formation of a mineralized matrix were observed with the addition of the nanosilicates to the collagen-based hydrogels. Overall, these results demonstrate the multiple functions of nanosilicates conducive to the regeneration of bone in nonunion defects, including increased network stiffness and porosity, injectability, and enhanced mineralized matrix formation in a growth-factor-free microenvironment.

  7. New tools for chloroplast genetic engineering allow the synthesis of human growth hormone in the green alga Chlamydomonas reinhardtii.

    Science.gov (United States)

    Wannathong, Thanyanan; Waterhouse, Janet C; Young, Rosanna E B; Economou, Chloe K; Purton, Saul

    2016-06-01

    In recent years, there has been an increasing interest in the exploitation of microalgae in industrial biotechnology. Potentially, these phototrophic eukaryotes could be used for the low-cost synthesis of valuable recombinant products such as bioactive metabolites and therapeutic proteins. The algal chloroplast in particular represents an attractive target for such genetic engineering, both because it houses major metabolic pathways and because foreign genes can be targeted to specific loci within the chloroplast genome, resulting in high-level, stable expression. However, routine methods for chloroplast genetic engineering are currently available only for one species-Chlamydomonas reinhardtii-and even here, there are limitations to the existing technology, including the need for an expensive biolistic device for DNA delivery, the lack of robust expression vectors, and the undesirable use of antibiotic resistance markers. Here, we describe a new strain and vectors for targeted insertion of transgenes into a neutral chloroplast locus that (i) allow scar-less fusion of a transgenic coding sequence to the promoter/5'UTR element of the highly expressed endogenous genes psaA or atpA, (ii) employ the endogenous gene psbH as an effective but benign selectable marker, and (iii) ensure the successful integration of the transgene construct in all transformant lines. Transformation is achieved by a simple and cheap method of agitation of a DNA/cell suspension with glass beads, with selection based on the phototrophic rescue of a cell wall-deficient ΔpsbH strain. We demonstrate the utility of these tools in the creation of a transgenic line that produces high levels of functional human growth hormone.

  8. Attenuation of skeletal muscle wasting with recombinant human growth hormone secreted from a tissue-engineered bioartificial muscle

    Science.gov (United States)

    Vandenburgh, H.; Del Tatto, M.; Shansky, J.; Goldstein, L.; Russell, K.; Genes, N.; Chromiak, J.; Yamada, S.

    1998-01-01

    Skeletal muscle wasting is a significant problem in elderly and debilitated patients. Growth hormone (GH) is an anabolic growth factor for skeletal muscle but is difficult to deliver in a therapeutic manner by injection owing to its in vivo instability. A novel method is presented for the sustained secretion of recombinant human GH (rhGH) from genetically modified skeletal muscle implants, which reduces host muscle wasting. Proliferating murine C2C12 skeletal myoblasts stably transduced with the rhGH gene were tissue engineered in vitro into bioartificial muscles (C2-BAMs) containing organized postmitotic myofibers secreting 3-5 microg of rhGH/day in vitro. When implanted subcutaneously into syngeneic mice, C2-BAMs delivered a sustained physiologic dose of 2.5 to 11.3 ng of rhGH per milliliter of serum. rhGH synthesized and secreted by the myofibers was in the 22-kDa monomeric form and was biologically active, based on downregulation of a GH-sensitive protein synthesized in the liver. Skeletal muscle disuse atrophy was induced in mice by hindlimb unloading, causing the fast plantaris and slow soleus muscles to atrophy by 21 to 35% ( < 0.02). This atrophy was significantly attenuated 41 to 55% (p < 0.02) in animals that received C2-BAM implants, but not in animals receiving daily injections of purified rhGH (1 mg/kg/day). These data support the concept that delivery of rhGH from BAMs may be efficacious in treating muscle-wasting disorders.

  9. Evaluation of the Growth Environment of a Hydrostatic Force Bioreactor for Preconditioning of Tissue-Engineered Constructs

    Science.gov (United States)

    Reinwald, Yvonne; Leonard, Katherine H.L.; Henstock, James R.; Whiteley, Jonathan P.; Osborne, James M.; Waters, Sarah L.; Levesque, Philippe

    2015-01-01

    Bioreactors have been widely acknowledged as valuable tools to provide a growth environment for engineering tissues and to investigate the effect of physical forces on cells and cell-scaffold constructs. However, evaluation of the bioreactor environment during culture is critical to defining outcomes. In this study, the performance of a hydrostatic force bioreactor was examined by experimental measurements of changes in dissolved oxygen (O2), carbon dioxide (CO2), and pH after mechanical stimulation and the determination of physical forces (pressure and stress) in the bioreactor through mathematical modeling and numerical simulation. To determine the effect of hydrostatic pressure on bone formation, chick femur skeletal cell-seeded hydrogels were subjected to cyclic hydrostatic pressure at 0–270 kPa and 1 Hz for 1 h daily (5 days per week) over a period of 14 days. At the start of mechanical stimulation, dissolved O2 and CO2 in the medium increased and the pH of the medium decreased, but remained within human physiological ranges. Changes in physiological parameters (O2, CO2, and pH) were reversible when medium samples were placed in a standard cell culture incubator. In addition, computational modeling showed that the distribution and magnitude of physical forces depends on the shape and position of the cell-hydrogel constructs in the tissue culture format. Finally, hydrostatic pressure was seen to enhance mineralization of chick femur skeletal cell-seeded hydrogels. PMID:24967717

  10. GENERIC VERIFICATION PROTOCOL FOR DETERMINATION OF EMISSIONS REDUCTIONS FROM SELECTIVE CATALYTIC REDUCTIONS CONTROL TECHNOLOGIES FOR HIGHWAY, NONROAD, AND STATIONARY USE DIESEL ENGINES

    Science.gov (United States)

    The protocol describes the Environmental Technology Verification (ETV) Program's considerations and requirements for verification of emissions reduction provided by selective catalytic reduction (SCR) technologies. The basis of the ETV will be comparison of the emissions and perf...

  11. Biodegradable chitosan scaffolds containing microspheres as carriers for controlled transforming growth factor-β1 delivery for cartilage tissue engineering

    Institute of Scientific and Technical Information of China (English)

    CAI Dao-zhang; ZENG Chun; QUAN Da-ping; BU Li-si; WANG Kun; LU Hua-ding; LI Xiao-feng

    2007-01-01

    TGF-β1 release group (92.4%±4.8%, P<0.05). Both the proliferation rate and production of collagen type Ⅱ in the transforming growth factor-β1 microsphere incorporated scaffolds were significantly higher than those in the scaffolds without microspheres, indicating that the activity of TGF-β1 was retained during microsphere fabrication and after growth factor release.Conclusion Chitosan microspheres can serve as delivery vehicles for controlled release of TGF-β1, and the released growth factor can augment chondrocytes proliferation and synthesis of extracellular matrix. Chitosan scaffolds incorporated with chitosan microspheres loaded with TGF-β1 possess a promising potential to be applied for controlled cytokine delivery and cartilage tissue engineering.

  12. New Engines for Growth

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ Most developed countries came out of the 2008-09 crisis in bad shape.Burdened with extreme debt and facing massive fiscal adjustments(or solvency crises of unimaginable consequences if they do not adjust)they can expect a slow,medium-term recovery at best.

  13. Growth and characterization of deposits in the combustion chamber of a diesel engine fueled with B50 and Indonesian biodiesel fuel (IBF

    Directory of Open Access Journals (Sweden)

    M Taufiq Suryantoro

    2016-12-01

    Full Text Available Although used since 1893, biodiesel still faces problems that must be overcome before it can fully replace petroleum diesel. Existing literature shows that continuous use of biodiesel could lead to higher growth of deposits on critical engine components, contributing to lots of problems that could ultimately decrease engine performance. In this context, endurance tests were performed to compare the impacts of B50 and Indonesian biodiesel fuel (IBF: diesel fuel containing 10% palm oil biodiesel on engine durability. More specifically, deposits growth as well as deposits structure and composition in response to the application of the above-mentioned fuel blends were investigated over 200 h. The results revealed that B50 produced relatively larger amounts of deposits especially on the valves and injector tip while also increased the risk of ring sticking. In addition, the structure and the elemental composition of the deposits formed on engine important components, i.e., injector tips, piston crown, intake/exhaust valves, cylinder head, and piston grooves when B50 was used were quite different compared with the IBF. Overall, more deposits formation was observed by increasing biodiesel inclusion rate while deposits tended to be wet and brittle as well.

  14. Effects of sawdust soil amendment on the soil, growth and yield ofSolanum esculentum Linn. in waste engine oil-polluted soil

    Institute of Scientific and Technical Information of China (English)

    Babalola E Akinpelumi; Olusanya A Olatunji

    2015-01-01

    This study investigated the effects of sawdust as a soil amendment on certain growth parameters ofSolanum esculentum Linn.grown in soil polluted with various concentrations of waste engine oil, and changes in the physicochemical proper-ties of the soil. The purpose was to assess the soil remediation potentials of sawdust in waste engine oil-polluted soil. The experiment was divided into three regimes: control (air-dried soil without waste engine oil and with clean sawdust), pol-luted (waste engine oil-contaminated soil), and amended (oil-polluted soil amended with sawdust). Enough 3-kg soil samples were sieved and air-dried to prepare five treatment levels of waste engine oil-contaminated soil (30 mL, 1%; 60 mL, 2%; 90 mL, 3%; 120 mL, 4%; and 150 mL, 5%), as well as five additional treatment levels (the same amounts of oil contamination) in soil amended with sawdust. The treatment levels were replicated five times in a completely randomized design. A nursery bed was planted with a hybrid tomato variety (Roma V F) obtained from National Horticultural Research Institute (NIHORT) in Ibadan, Nigeria. During the maturation period, the growth parameters such as plant height, number of leaves, and number of branches per plant were determined and then the harvested plants were oven dried at 70 °C for 48 hours to determine their dry weights. The effects of the sawdust amendment on the soil were assessed by determining the soil pH (glass electrode pH meter),total nitrogen (Kjeldahl method), total phosphorus (Bray-1 solution), and potassium (on the leacheate by a flame photometer). Chromium, lead, and cadmium contents were determined using an atomic absorption spectrophotometer. Analysis of variance and a Duncan multiple-range test were employed to test significant differences in the soil properties of the three regimes. The growth performance ofSolanum esculentumLinn. in the amended regime (soil with sawdust) at the 150-mL waste engine oil-contamination level was

  15. About recent developments of synthetic polymers for a suitable cell adhesion/growth support in tissue engineering-based either augmentation cystoplasty or neobladder.

    Science.gov (United States)

    Alberti, Contardo

    2014-01-01

    Among the regenerative medicine technologies, the tissue engineering has emerged, in recent years, as a prominent tool, particularly given the tremendous developments in the field of synthetic polymer-based scaffolds. Scaffold surface coatings with either extracellular matrix (ECM) proteins or integrin-binding bioactive peptide sequences, such as RDG, proved to be extremely useful to enhance cell adhesion and growth. Nevertheless, about it, excellent effects may be reached by electrospinning-obtained nanofiber-structured synthetic polymer scaffold – such as polyurethane or polyethylene-terephthalate electrospun nanofibers – without resorting to surface- coated adhesion proteins. As for bladder tissue engineering, properly cell-seeded synthetic biomaterial-based scaffolds allow today timely chances to obtain constructs provided with specific bladder native tissue-like both histological-immunohistochemical and functional-dynamic features. Recent bright advances in the tissue engineering research, particularly in the area of materials science – together with increasing availability of suitable bioreactors – and stem cell biology, make foreseeable, in the near future, further technological improvements that might widen the clinical applications of bladder tissue engineering up to whole bladder replacement in radical tumor surgery.

  16. An Assessment of Engineered Calcium Oxalate Crystal Formation on Plant Growth and Development as a Step toward Evaluating Its Use to Enhance Plant Defense.

    Science.gov (United States)

    Nakata, Paul A

    2015-01-01

    The establishment of new approaches to control chewing insects has been sought not only for direct use in reducing crop loss but also in managing resistance to the pesticides already in use. Engineered formation of calcium oxalate crystals is a potential strategy that could be developed to fulfill both these needs. As a step toward this development, this study investigates the effects of transforming a non-calcium oxalate crystal accumulating plant, Arabidopsis thaliana, into a crystal accumulating plant. Calcium oxalate crystal accumulating A. thaliana lines were generated by ectopic expression of a single bacterial gene encoding an oxalic acid biosynthetic enzyme. Biochemical and cellular studies suggested that the engineered A. thaliana lines formed crystals of calcium oxalate in a manner similar to naturally occurring crystal accumulating plants. The amount of calcium oxalate accumulated in leaves also reached levels similar to those measured in the leaves of Medicago truncatula in which the crystals are known to play a defensive role. Visual inspection of the different engineered lines, however, suggested a phenotypic consequence on plant growth and development with higher calcium oxalate concentrations. The restoration of a near wild-type plant phenotype through an enzymatic reduction of tissue oxalate supported this observation. Overall, this study is a first to provide initial insight into the potential consequences of engineering calcium oxalate crystal formation in non-crystal accumulating plants.

  17. Assessment of crack growth in a space shuttle main engine first-stage, high-pressure fuel turbopump blade

    Science.gov (United States)

    Abdul-Aziz, Ali

    1993-01-01

    A two-dimensional finite element fracture mechanics analysis of a space shuttle main engine (SSME) turbine blade firtree was performed using the MARC finite element code. The analysis was conducted under combined effects of thermal and mechanical loads at steady-state conditions. Data from a typical engine stand cycle of the SSME were used to run a heat transfer analysis and, subsequently, a thermal structural fracture mechanics analysis. Temperature and stress contours for the firtree under these operating conditions were generated. High stresses were found at the firtree lobes where crack initiation was triggered. A life assessment of the firtree was done by assuming an initial and a final crack size.

  18. An engineered transforming growth factor β (TGF-β) monomer that functions as a dominant negative to block TGF-β signaling

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sun Kyung; Barron, Lindsey; Hinck, Cynthia S.; Petrunak, Elyse M.; Cano, Kristin E.; Thangirala, Avinash; Iskra, Brian; Brothers, Molly; Vonberg, Machell; Leal, Belinda; Richter, Blair; Kodali, Ravindra; Taylor, Alexander B.; Du, Shoucheng; Barnes, Christopher O.; Sulea, Traian; Calero, Guillermo; Hart, P. John; Hart, Matthew J.; Demeler, Borries; Hinck, Andrew P. (Texas-HSC); (NRCC); (Pitt)

    2017-02-22

    The transforming growth factor β isoforms, TGF-β1, -β2, and -β3, are small secreted homodimeric signaling proteins with essential roles in regulating the adaptive immune system and maintaining the extracellular matrix. However, dysregulation of the TGF-β pathway is responsible for promoting the progression of several human diseases, including cancer and fibrosis. Despite the known importance of TGF-βs in promoting disease progression, no inhibitors have been approved for use in humans. Herein, we describe an engineered TGF-β monomer, lacking the heel helix, a structural motif essential for binding the TGF-β type I receptor (TβRI) but dispensable for binding the other receptor required for TGF-β signaling, the TGF-β type II receptor (TβRII), as an alternative therapeutic modality for blocking TGF-β signaling in humans. As shown through binding studies and crystallography, the engineered monomer retained the same overall structure of native TGF-β monomers and bound TβRII in an identical manner. Cell-based luciferase assays showed that the engineered monomer functioned as a dominant negative to inhibit TGF-β signaling with a Ki of 20–70 nM. Investigation of the mechanism showed that the high affinity of the engineered monomer for TβRII, coupled with its reduced ability to non-covalently dimerize and its inability to bind and recruit TβRI, enabled it to bind endogenous TβRII but prevented it from binding and recruiting TβRI to form a signaling complex. Such engineered monomers provide a new avenue to probe and manipulate TGF-β signaling and may inform similar modifications of other TGF-β family members.

  19. Engineered Resistant-Starch (ERS) Diet Shapes Colon Microbiota Profile in Parallel with the Retardation of Tumor Growth in In Vitro and In Vivo Pancreatic Cancer Models.

    Science.gov (United States)

    Panebianco, Concetta; Adamberg, Kaarel; Adamberg, Signe; Saracino, Chiara; Jaagura, Madis; Kolk, Kaia; Di Chio, Anna Grazia; Graziano, Paolo; Vilu, Raivo; Pazienza, Valerio

    2017-03-27

    Pancreatic cancer (PC) is ranked as the fourth leading cause of cancer-related deaths worldwide. Despite recent advances in treatment options, a modest impact on the outcome of the disease is observed so far. We have previously demonstrated that short-term fasting cycles have the potential to improve the efficacy of chemotherapy against PC. The aim of this study was to assess the effect of an engineered resistant-starch (ERS) mimicking diet on the growth of cancer cell lines in vitro, on the composition of fecal microbiota, and on tumor growth in an in vivo pancreatic cancer mouse xenograft model. BxPC-3, MIA PaCa-2 and PANC-1 cells were cultured in the control, and in the ERS-mimicking diet culturing condition, to evaluate tumor growth and proliferation pathways. Pancreatic cancer xenograft mice were subjected to an ERS diet to assess tumor volume and weight as compared to mice fed with a control diet. The composition and activity of fecal microbiota were further analyzed in growth experiments by isothermal microcalorimetry. Pancreatic cancer cells cultured in an ERS diet-mimicking medium showed decreased levels of phospho-ERK1/2 (extracellular signal-regulated kinase proteins) and phospho-mTOR (mammalian target of rapamycin) levels, as compared to those cultured in standard medium. Consistently, xenograft pancreatic cancer mice subjected to an ERS diet displayed significant retardation in tumor growth. In in vitro growth experiments, the fecal microbial cultures from mice fed with an ERS diet showed enhanced growth on residual substrates, higher production of formate and lactate, and decreased amounts of propionate, compared to fecal microbiota from mice fed with the control diet. A positive effect of the ERS diet on composition and metabolism of mouse fecal microbiota shown in vitro is associated with the decrease of tumor progression in the in vivo PC xenograft mouse model. These results suggest that engineered dietary interventions could be supportive as a

  20. Computational modeling of adherent cell growth in a hollow-fiber membrane bioreactor for large-scale 3-D bone tissue engineering.

    Science.gov (United States)

    Mohebbi-Kalhori, Davod; Behzadmehr, Amin; Doillon, Charles J; Hadjizadeh, Afra

    2012-09-01

    The use of hollow-fiber membrane bioreactors (HFMBs) has been proposed for three-dimensional bone tissue growth at the clinical scale. However, to achieve an efficient HFMB design, the relationship between cell growth and environmental conditions must be determined. Therefore, in this work, a dynamic double-porous media model was developed to determine nutrient-dependent cell growth for bone tissue formation in a HFMB. The whole hollow-fiber scaffold within the bioreactor was treated as a porous domain in this model. The domain consisted of two interpenetrating porous regions, including a porous lumen region available for fluid flow and a porous extracapillary space filled with a collagen gel that contained adherent cells for promoting long-term growth into tissue-like mass. The governing equations were solved numerically and the model was validated using previously published experimental results. The contributions of several bioreactor design and process parameters to the performance of the bioreactor were studied. The results demonstrated that the process and design parameters of the HFMB significantly affect nutrient transport and thus cell behavior over a long period of culture. The approach presented here can be applied to any cell type and used to develop tissue engineering hollow-fiber scaffolds.

  1. 工程弃渣用作植物生长基质的研究%Experimental Study on the Use of Engineering Spoil for Plant Growth Substrate

    Institute of Scientific and Technical Information of China (English)

    陈述悦; 顾卫; 戴泉玉

    2012-01-01

    In order to effectively utilize the engineering waste material, engineering spoil with particle size less than 2 mm was mixed with natural surface soil to form suhstrate for plant growth in this study. The result indicated that 50%-70% volumetric ratio of engineering spoil was preferable; the spoil with higher weathering degree had better nutrient and pH condition, water retention capability and drought resistance that facilitate plant growth; however, the nutrient content in engineering spoil was relatively low, thus additional fer- tilizer was required to meet the needs of plant growth; there was no significant difference in three-phase com- position among the substrates with different spoil and soil proportions, but obvious variation tendencies were observed in pH, nutrient contents, soil moisture constant, seed germination rate and plant survival rate.%为资源化利用工程弃渣,对粒径〈2mm的工程弃渣和自然土壤进行了不同体积配比生长实验,结果表明:粒径小于2mm的工程弃渣与自然土壤混合后可以用作植物生长基质,工程弃渣的使用体积比例以50%~70%为宜;工程弃渣风化程度越高,其养分含量、pH值及抗旱保墒能力越适合植物生长,但工程弃渣的养分含量一般比较贫乏,需额外添加肥料才能满足植物生长对养分的需求;工程弃渣与自然土壤不同体积配比的混合物的三相没有明显变化规律,但混合物的pH值、养分含量、土壤水分常数、种子发芽率、植株保存率等指标随工程弃渣的体积比例变化而规律变化。

  2. Controlled Dual Growth Factor Delivery From Microparticles Incorporated Within Human Bone Marrow-Derived Mesenchymal Stem Cell Aggregates for Enhanced Bone Tissue Engineering via Endochondral Ossification.

    Science.gov (United States)

    Dang, Phuong N; Dwivedi, Neha; Phillips, Lauren M; Yu, Xiaohua; Herberg, Samuel; Bowerman, Caitlin; Solorio, Loran D; Murphy, William L; Alsberg, Eben

    2016-02-01

    Bone tissue engineering via endochondral ossification has been explored by chondrogenically priming cells using soluble mediators for at least 3 weeks to produce a hypertrophic cartilage template. Although recapitulation of endochondral ossification has been achieved, long-term in vitro culture is required for priming cells through repeated supplementation of inductive factors in the media. To address this challenge, a microparticle-based growth factor delivery system was engineered to drive endochondral ossification within human bone marrow-derived mesenchymal stem cell (hMSC) aggregates. Sequential exogenous presentation of soluble transforming growth factor-β1 (TGF-β1) and bone morphogenetic protein-2 (BMP-2) at various defined time courses resulted in varying degrees of chondrogenesis and osteogenesis as demonstrated by glycosaminoglycan and calcium content. The time course that best induced endochondral ossification was used to guide the development of the microparticle-based controlled delivery system for TGF-β1 and BMP-2. Gelatin microparticles capable of relatively rapid release of TGF-β1 and mineral-coated hydroxyapatite microparticles permitting more sustained release of BMP-2 were then incorporated within hMSC aggregates and cultured for 5 weeks following the predetermined time course for sequential presentation of bioactive signals. Compared with cell-only aggregates treated with exogenous growth factors, aggregates with incorporated TGF-β1- and BMP-2-loaded microparticles exhibited enhanced chondrogenesis and alkaline phosphatase activity at week 2 and a greater degree of mineralization by week 5. Staining for types I and II collagen, osteopontin, and osteocalcin revealed the presence of cartilage and bone. This microparticle-incorporated system has potential as a readily implantable therapy for healing bone defects without the need for long-term in vitro chondrogenic priming. Significance: This study demonstrates the regulation of chondrogenesis

  3. Effects of growth factors and glucosamine on porcine mandibular condylar cartilage cells and hyaline cartilage cells for tissue engineering applications.

    Science.gov (United States)

    Wang, Limin; Detamore, Michael S

    2009-01-01

    Temporomandibular joint (TMJ) condylar cartilage is a distinct cartilage that has both fibrocartilaginous and hyaline-like character, with a thin proliferative zone that separates the fibrocartilaginous fibrous zone at the surface from the hyaline-like mature and hypertrophic zones below. In this study, we compared the effects of insulin-like growth factor-I (IGF-I), basic fibroblast growth factor (bFGF), transforming growth factor beta1 (TGF-beta1), and glucosamine sulphate on porcine TMJ condylar cartilage and ankle cartilage cells in monolayer culture. In general, TMJ condylar cartilage cells proliferated faster than ankle cartilage cells, while ankle cells produced significantly greater amounts of glycosaminoglycans (GAGs) and collagen than TMJ condylar cartilage cells. IGF-I and bFGF were potent stimulators of TMJ cell proliferation, while no signals statistically outperformed controls for ankle cell proliferation. IGF-I was the most effective signal for GAG production with ankle cells, and the most potent upregulator of collagen synthesis for both cell types. Glucosamine sulphate promoted cell proliferation and biosynthesis at specific concentrations and outperformed growth factors in certain instances. In conclusion, hyaline cartilage cells had lower cell numbers and superior biosynthesis compared to TMJ condylar cartilage cells, and we have found IGF-I at 100 ng/mL and glucosamine sulphate at 100 microg/mL to be the most effective signals for these cells under the prescribed conditions.

  4. Software engineering

    CERN Document Server

    Sommerville, Ian

    2016-01-01

    For courses in computer science and software engineering The Fundamental Practice of Software Engineering Software Engineering introduces readers to the overwhelmingly important subject of software programming and development. In the past few years, computer systems have come to dominate not just our technological growth, but the foundations of our world's major industries. This text seeks to lay out the fundamental concepts of this huge and continually growing subject area in a clear and comprehensive manner. The Tenth Edition contains new information that highlights various technological updates of recent years, providing readers with highly relevant and current information. Sommerville's experience in system dependability and systems engineering guides the text through a traditional plan-based approach that incorporates some novel agile methods. The text strives to teach the innovators of tomorrow how to create software that will make our world a better, safer, and more advanced place to live.

  5. 消费已成为经济增长的主引擎%Consumption has already become the main engine of the economic growth

    Institute of Scientific and Technical Information of China (English)

    严先溥

    2015-01-01

    近年来消费对经济增长的贡献率逐步增高,消费“马车”已成为拉动经济增长的主引擎。通过数据分析可以看出消费新格局正逐步形成,既体现在增长速度上,更体现在消费和流通产业对国民经济增长的拉动力显著增强。居民可支配收入的增长、政策面扩大就业以及互联网+和物联网技术的推广等多种因素支撑消费成为经济增长的第一动力,消费新热点和新趋势正在加快形成。为顺应消费新变化,未来“十三五”乃至更长时期,建议从六个方面入手加快推动消费增长格局的形成。%The contribution rate of the consumption to the economic growth has gradually increased in recent years. Consumption “carriage” has already become the main engine of the economic growth. The data analysis has shown that the new pattern of consumption is gradually forming, which is not only embodied in the rate of growth, but even embodied in the significantly enhanced pull power of the consumption and circulation industry to the na-tional economic growth. There are various factors such as the growth of the disposable income, the policy to ex-pand employment, the Internet plus and Internet of things technology have become the first motive power of the e-conomic growth. The new hotspot and trends of the consumption are speeding up the formation. In order to adapt to the new changes in consumption, we need to promote the formation of the consumption growth pattern from six as-pects in the 13 th five year period and even a longer time.

  6. Enabling area-selective potential-energy engineering in InGaN/GaN quantum wells by post-growth intermixing

    KAUST Repository

    Shen, Chao

    2015-03-19

    We report on a unique area-selective, post-growth approach in engineering the quantum-confined potential-energy profile of InGaN/GaN quantum wells (QWs) utilizing metal/dielectric-coating induced intermixing process. This led to simultaneous realization of adjacent regions with peak emission of 2.74 eV and 2.82 eV with a high spatial resolution (~1 μm) at the coating boundary. The potential profile softening in the intermixed QW light-emitting diode (LED) was experimentally and numerically correlated, shedding light on the origin of alleviated efficiency droop from 30.5% to 16.6% (at 150 A/cm2). The technique is advantageous for fabricating high efficiency light-emitters, and is amenable to monolithic integration of nitride-based photonic devices.

  7. Engineered collagen hydrogels for the sustained release of biomolecules and imaging agents: promoting the growth of human gingival cells.

    Science.gov (United States)

    Choi, Jonghoon; Park, Hoyoung; Kim, Taeho; Jeong, Yoon; Oh, Myoung Hwan; Hyeon, Taeghwan; Gilad, Assaf A; Lee, Kwan Hyi

    2014-01-01

    We present here the in vitro release profiles of either fluorescently labeled biomolecules or computed tomography contrast nanoagents from engineered collagen hydrogels under physiological conditions. The collagen constructs were designed as potential biocompatible inserts into wounded human gingiva. The collagen hydrogels were fabricated under a variety of conditions in order to optimize the release profile of biomolecules and nanoparticles for the desired duration and amount. The collagen constructs containing biomolecules/nanoconstructs were incubated under physiological conditions (ie, 37°C and 5% CO2) for 24 hours, and the release profile was tuned from 20% to 70% of initially loaded materials by varying the gelation conditions of the collagen constructs. The amounts of released biomolecules and nanoparticles were quantified respectively by measuring the intensity of fluorescence and X-ray scattering. The collagen hydrogel we fabricated may serve as an efficient platform for the controlled release of biomolecules and imaging agents in human gingiva to facilitate the regeneration of oral tissues.

  8. Trust growth model of engineering project partnership pattern%工程项目伙伴关系模式的信任增长模型

    Institute of Scientific and Technical Information of China (English)

    刘家锋

    2011-01-01

    将信任分为初步交易型、深度交易型和义利共生型,运用博弈论分析不同信任的产生机制,并建立工程项目伙伴关系模式的信任增长模型.研究结果表明:企业之间共同的追求目标、价值观和文化理念是信任产生和不断增长的源泉.随着信任程度的加深,业主、监理单位和承包商各自获得的总体效益呈渐进上升趋势,参与工程建设的各方才能够形成战略型的永久伙伴关系.%The trust was divided into preliminary transaction, depth transaction and the righteousness favorable par agenesis. The generation mechanism of different trusts with the game theory was analyzed, and the trust growth model of engineering project partnership pattern was suggested. It is suggested that the common goal, values and cultural idea of different enterprises are the source of the trust origin and growth. With trust degree increasing, the total benefit that the owner, the construction supervision unit and the contractor obtain goes up gradually and the strategy permanent partnership between the participations of the engineering construction can be formed.

  9. THE ROLE OF IRON IN Deinococcus radiodurans ENGINEERED FOR GROWTH ON TOLUENE AND THE ROLE OF MANGANESE IN THE EXTREME RADIATION RESISTANCE PHENOTYPE

    Energy Technology Data Exchange (ETDEWEB)

    Hassan Brim; Elena K. Gaidamakova; Vera Y. Matrosova; Min Zhai; Amudhan Venkateswaran; Marina Omelchenko; Kira S. Makarova; Lawrence P. Wackett; James K. Fredrickson; Michael J. Daly

    2004-03-17

    Toluene and other fuel hydrocarbons are commonly found in association with radionuclides at numerous Department of Energy (DOE) sites, frequently occurring together with Cr(VI) and other heavy metals. In this study, the extremely radiation resistant bacterium Deinococcus radiodurans was engineered for complete toluene mineralization by cloned expression of tod and xyl genes of Pseudomonas putida. The recombinant Tod/Xyl strain showed significant incorporation of carbon from the toluene aromatic ring into cellular macromolecules and carbon dioxide, in the absence or presence of chronic radiation. We have shown that intracellular iron concentrations in wild-type D. radiodurans in minimal medium are exceptionally low and not sufficient to support growth on toluene using Fe-dependent oxygenases cloned from P. putida. Introducing the fur mutation into D. radiodurans increased intracellular Fe levels, and imparted on the engineered strain the ability to grow on meta-toluate as the sole carbon and energy source. The organism's native Cr(VI) reduction capabilities were facilitated by toluene when present as the sole carbon and energy source in natural sediment analogues of DOE contaminated environments. The engineered bacteria were able to oxidize toluene under both minimal and complex nutrient conditions, which is important since both conditions have environmental equivalents in the context of bioremediation processes. As such, the Tod/Xyl strain is providing a model for understanding the role of Fe and reduction of metals coupled to organic contaminant oxidation in aerobic radionuclide contaminated sediments. We have shown that D. radiodurans contains high intracellular manganese levels, and that Mn restriction sensitizes cells to irradiation. We propose that the unusually high Mn/Fe ratio of D. radiodurans facilitates survival by quenching oxidative stress during recovery.

  10. THE ROLE OF IRON IN Deinococcus radiodurans ENGINEERED FOR GROWTH ON TOLUENE AND THE ROLE OF MANGANESE IN THE EXTREME RADIATION RESISTANCE PHENOTYPE

    Energy Technology Data Exchange (ETDEWEB)

    Hassan Brim; Elena K. Gaidamakova; Vera Y. Matrosova; Min Zhai; Amudhan Venkateswaran; Marina Omelchenko; Kira S. Makarova; Lawrence P. Wackett; James K. Fredrickson; Michael J. Daly

    2004-03-17

    Toluene and other fuel hydrocarbons are commonly found in association with radionuclides at numerous Department of Energy (DOE) sites, frequently occurring together with Cr(VI) and other heavy metals. In this study, the extremely radiation resistant bacterium Deinococcus radiodurans was engineered for complete toluene mineralization by cloned expression of tod and xyl genes of Pseudomonas putida. The recombinant Tod/Xyl strain showed significant incorporation of carbon from the toluene aromatic ring into cellular macromolecules and carbon dioxide, in the absence or presence of chronic radiation. We have shown that intracellular iron concentrations in wild-type D. radiodurans in minimal medium are exceptionally low and not sufficient to support growth on toluene using Fe-dependent oxygenases cloned from P. putida. Introducing the fur mutation into D. radiodurans increased intracellular Fe levels, and imparted on the engineered strain the ability to grow on meta-toluate as the sole carbon and energy source. The organism's native Cr(VI) reduction capabilities were facilitated by toluene when present as the sole carbon and energy source in natural sediment analogues of DOE contaminated environments. The engineered bacteria were able to oxidize toluene under both minimal and complex nutrient conditions, which is important since both conditions have environmental equivalents in the context of bioremediation processes. As such, the Tod/Xyl strain is providing a model for understanding the role of Fe and reduction of metals coupled to organic contaminant oxidation in aerobic radionuclide contaminated sediments. We have shown that D. radiodurans contains high intracellular manganese levels, and that Mn restriction sensitizes cells to irradiation. We propose that the unusually high Mn/Fe ratio of D. radiodurans facilitates survival by quenching oxidative stress during recovery.

  11. Conjugation with RGD Peptides and Incorporation of Vascular Endothelial Growth Factor Are Equally Efficient for Biofunctionalization of Tissue-Engineered Vascular Grafts

    Directory of Open Access Journals (Sweden)

    Larisa V. Antonova

    2016-11-01

    Full Text Available The blend of poly(3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV and poly(ε-caprolactone (PCL has recently been considered promising for vascular tissue engineering. However, it was shown that PHBV/PCL grafts require biofunctionalization to achieve high primary patency rate. Here we compared immobilization of arginine–glycine–aspartic acid (RGD-containing peptides and the incorporation of vascular endothelial growth factor (VEGF as two widely established biofunctionalization approaches. Electrospun PHBV/PCL small-diameter grafts with either RGD peptides or VEGF, as well as unmodified grafts were implanted into rat abdominal aortas for 1, 3, 6, and 12 months following histological and immunofluorescence assessment. We detected CD31+/CD34+/vWF+ cells 1 and 3 months postimplantation at the luminal surface of PHBV/PCL/RGD and PHBV/PCL/VEGF, but not in unmodified grafts, with the further observation of CD31+CD34−vWF+ phenotype. These cells were considered as endothelial and produced a collagen-positive layer resembling a basement membrane. Detection of CD31+/CD34+ cells at the early stages with subsequent loss of CD34 indicated cell adhesion from the bloodstream. Therefore, either conjugation with RGD peptides or the incorporation of VEGF promoted the formation of a functional endothelial cell layer. Furthermore, both modifications increased primary patency rate three-fold. In conclusion, both of these biofunctionalization approaches can be considered as equally efficient for the modification of tissue-engineered vascular grafts.

  12. Antibacterial application of engineered bacteriophage nanomedicines: antibody-targeted, chloramphenicol prodrug loaded bacteriophages for inhibiting the growth of Staphylococcus aureus bacteria.

    Science.gov (United States)

    Vaks, Lilach; Benhar, Itai

    2011-01-01

    The increasing development of bacterial resistance to traditional antibiotics has reached alarming levels, thus there is an urgent need to develop new antimicrobial agents. To be effective, these new antimicrobials should possess novel modes of action and/or different cellular targets compared with existing antibiotics. Bacteriophages (phages) have been used for over a century as tools for the treatment of bacterial infections, for nearly half a century as tools in genetic research, for about two decades as tools for the discovery of specific target-binding proteins and peptides, and for almost a decade as tools for vaccine development. We describe a new application in the area of antibacterial nanomedicines where filamentous phages can be formulated as targeted drug-delivery vehicles of nanometric dimensions (phage nanomedicines) and used for therapeutic purposes. This protocol involves both genetic and chemical engineering of these phages. The genetic engineering of the phage coat, which results in the display of a target-specificity-conferring peptide or protein on the phage coat, can be used to design the drug-release mechanism and is not described herein. However, the methods used to chemically conjugate cytotoxic drugs at high density on the phage coat are described. Further, assays to measure the drug load on the surface of the phage and the potency of the system in the inhibition of growth of target cells as well as assessment of the therapeutic potential of the phages in a mouse disease model are discussed.

  13. Heparin/collagen encapsulating nerve growth factor multilayers coated aligned PLLA nanofibrous scaffolds for nerve tissue engineering.

    Science.gov (United States)

    Zhang, Kuihua; Huang, Dianwu; Yan, Zhiyong; Wang, Chunyang

    2017-07-01

    Biomimicing topological structure of natural nerve tissue to direct axon growth and controlling sustained release of moderate neurotrophic factors are extremely propitious to the functional recovery of damaged nervous systems. In this study, the heparin/collagen encapsulating nerve growth factor (NGF) multilayers were coated onto the aligned poly-L-lactide (PLLA) nanofibrous scaffolds via a layer-by-layer (LbL) self-assembly technique to combine biomolecular signals, and physical guidance cues for peripheral nerve regeneration. Scanning electronic microscopy (SEM) revealed that the surface of aligned PLLA nanofibrous scaffolds coated with heparin/collagen multilayers became rougher and appeared some net-like filaments and protuberances in comparison with PLLA nanofibrous scaffolds. The heparin/collagen multilayers did not destroy the alignment of nanofibers. X-ray photoelectron spectroscopy and water contact angles displayed that heparin and collagen were successfully coated onto the aligned PLLA nanofibrous scaffolds and improved its hydrophilicity. Three-dimensional (3 D) confocal microscopy images further demonstrated that collagen, heparin, and NGF were not only coated onto the surface of aligned PLLA nanofibrous scaffolds but also permeated into the inner of scaffolds. Moreover, NGF presented a sustained release for 2 weeks from aligned nanofibrous scaffolds coated with 5.5 bilayers or above and remained good bioactivity. The heparin/collagen encapsulating NGF multilayers coated aligned nanofibrous scaffolds, in particular 5.5 bilayers or above, was more beneficial to Schwann cells (SCs) proliferation and PC12 cells differentiation as well as the SC cytoskeleton and neurite growth along the direction of nanofibrous alignment compared to the aligned PLLA nanofibrous scaffolds. This novel scaffolds combining sustained release of bioactive NGF and aligned nanofibrous topography presented an excellent potential in peripheral nerve regeneration. © 2016 Wiley

  14. Exhaust emissions from small engines in handheld devices

    Directory of Open Access Journals (Sweden)

    Lijewski Piotr

    2017-01-01

    Full Text Available The paper presents the results of investigations on the exhaust emissions carried out under real operating conditions of gasoline engines operating in a power generator and a chainsaw. During the operation of these devices the authors measured the following exhaust emissions: CO, HC, NOx and CO2. For the measurements the authors used a portable exhaust emission analyzer SEMTECH DS by SENSORS. This analyzer measures the concentrations of the exhaust gas components in an on-line mode while the engine is running under real operating conditions (road, field etc.. The exhaust emissions tests of non-road engine applications are performed on engine test beds in the NRSC (ISO 8178 and NRTC tests. The presented method is a new solution in determining of the exhaust emissions from such engines. The obtained results were compared with the applicable emission requirements. Besides, based on the performed investigations, the authors attempted an evaluation of the possibilities of the use of the measurement method for development works related to the reduction of the emission from small gasoline engines.

  15. Hybrid use of combined and sequential delivery of growth factors and ultrasound stimulation in porous multilayer composite scaffolds to promote both vascularization and bone formation in bone tissue engineering.

    Science.gov (United States)

    Yan, Haoran; Liu, Xia; Zhu, Minghua; Luo, Guilin; Sun, Tao; Peng, Qiang; Zeng, Yi; Chen, Taijun; Wang, Yingying; Liu, Keliang; Feng, Bo; Weng, Jie; Wang, Jianxin

    2016-01-01

    In this study, a multilayer coating technology would be adopted to prepare a porous composite scaffold and the growth factor release and ultrasound techniques were introduced into bone tissue engineering to finally solve the problems of vascularization and bone formation in the scaffold whilst the designed multilayer composite with gradient degradation characteristics in the space was used to match the new bone growth process better. The results of animal experiments showed that the use of low intensity pulsed ultrasound (LIPUS) combined with growth factors demonstrated excellent capabilities and advantages in both vascularization and new bone formation in bone tissue engineering. The degradation of the used scaffold materials could match new bone formation very well. The results also showed that only RGD-promoted cell adhesion was insufficient to satisfy the needs of new bone formation while growth factors and LIPUS stimulation were the key factors in new bone formation.

  16. Lentivirally engineered dendritic cells activate AFP-specific T cells which inhibit hepatocellular carcinoma growth in vitro and in vivo.

    Science.gov (United States)

    Liu, Yang; Butterfield, Lisa H; Fu, Xiaohui; Song, Zhenshun; Zhang, Xiaoping; Lu, Chongde; Ding, Guanghui; Wu, Mengchao

    2011-07-01

    α-fetoprotein (AFP), a tumor-associated antigen for hepatocellular carcinoma (HCC), is an established biomarker for HCC. In this study, we created a lentivirus expressing the AFP antigen and investigated the anti-tumor activity of AFP-specific CD8+ T cells, with and without CD4+ T cells, which were activated by either AFP peptide-pulsed or Lenti-AFP-engineered Dendritic cells (DCs) in vitro and in vivo. AFP-specific T cells could efficiently kill HepG2 HCC cells, and produced IL-2, IFN-γ, TNF-α, perforin and granzyme B, with minimal production of IL-10 (a negative regulator of T cell activation). Both strategies activated AFP-specific T cells, but the lentiviral strategy was superior by several measures. Data also support an impact of CD4+ T cells in supporting anti-tumor activity. In vivo studies in a xenograft HCC tumor model also showed that AFP-specific T cells could markedly suppress HCC tumor formation and morbidity in tumor-bearing nude mice, as well as regulate serum levels of related cytokines and anti-tumor molecules. In parallel with human in vitro T cell cultures, the in vivo model demonstrated superior anti-tumor effects and Th1-skewing with Lenti-AFP-DCs. This study supports the superiority of a full-length antigen lentivirus-based DCs vaccine strategy over peptides, and provides new insight into the design of DCs-based vaccines.

  17. Direct hydrogel encapsulation of pluripotent stem cells enables ontomimetic differentiation and growth of engineered human heart tissues.

    Science.gov (United States)

    Kerscher, Petra; Turnbull, Irene C; Hodge, Alexander J; Kim, Joonyul; Seliktar, Dror; Easley, Christopher J; Costa, Kevin D; Lipke, Elizabeth A

    2016-03-01

    Human engineered heart tissues have potential to revolutionize cardiac development research, drug-testing, and treatment of heart disease; however, implementation is limited by the need to use pre-differentiated cardiomyocytes (CMs). Here we show that by providing a 3D poly(ethylene glycol)-fibrinogen hydrogel microenvironment, we can directly differentiate human pluripotent stem cells (hPSCs) into contracting heart tissues. Our straight-forward, ontomimetic approach, imitating the process of development, requires only a single cell-handling step, provides reproducible results for a range of tested geometries and size scales, and overcomes inherent limitations in cell maintenance and maturation, while achieving high yields of CMs with developmentally appropriate temporal changes in gene expression. We demonstrate that hPSCs encapsulated within this biomimetic 3D hydrogel microenvironment develop into functional cardiac tissues composed of self-aligned CMs with evidence of ultrastructural maturation, mimicking heart development, and enabling investigation of disease mechanisms and screening of compounds on developing human heart tissue.

  18. Properties of jet engine combustion particles during the PartEmis experiment. Hygroscopic growth at supersaturated conditions

    Science.gov (United States)

    Hitzenberger, R.; Giebl, H.; Petzold, A.; Gysel, M.; Nyeki, S.; Weingartner, E.; Baltensperger, U.; Wilson, C. W.

    2003-07-01

    During the EU Project PartEmis, the microphysical properties of aircraft combustion aerosol were investigated. This study is focused on the ability of exhaust aerosols to act as cloud condensation nuclei (CCN). The combustor was operated at two different conditions representing old and modern aircraft engine technology. CCN concentrations were measured with the University of Vienna CCN counter [ Giebl et al., 2002] at supersaturations around 0.7%. The activation ratio (fraction of CCN in total aerosol) depended on the fuel sulphur content (FSC) and also on the operation conditions. CCN/CN ratios increased from 0.93 through 1.43 to 5.15 . 10-3 (old cruise conditions) and 0.67 through 3.04 to 7.94 . 10-3 (modern cruise conditions) when FSC increased from 50 through 410 to1270 μg/g. The activation behaviour was modelled using classical theories and with a semi-empirical model [ Gysel et al., 2003] based on measured hygroscopicity of the aerosol under subsaturated conditions, which gave the best agreement.

  19. Enhancing neuronal growth from human endometrial stem cells derived neuron-like cells in three-dimensional fibrin gel for nerve tissue engineering.

    Science.gov (United States)

    Navaei-Nigjeh, Mona; Amoabedini, Ghasem; Noroozi, Abbas; Azami, Mahmoud; Asmani, Mohammad N; Ebrahimi-Barough, Somayeh; Saberi, Hooshang; Ai, Armin; Ai, Jafar

    2014-08-01

    Nerve tissue engineering (NTE) is one of the most promising methods to restore central nerve systems in human health care. Three-dimensional (3D) distribution and growth of cells within the porous scaffold composed of nanofibers are of clinical significance for NTE. In this study, an attempt was made to develop and characterize the use of fibrin gel and human endometrial stem cells (hEnSCs)-derived neuron-like cells simultaneously to support cell behavior especially neuron outgrowth. The structural and mechanical characteristics of fibrin gel scaffold were examined with SEM and rheometer. Also, hEnSCs-derived neuron-like cells were cultured in fibrin gel and were subsequently analyzed with immunofluorescent staining against neuronal markers. In parallel, the survival and growth rates of the cells were determined by MTT assay and neurite extension. At the end, cell-matrix interactions were investigated with SEM and TEM micrographs. Mechanical properties of fabricated scaffold were studied and results indicated appropriate choice of material, SEM and TEM showed excellent integration of cells with nanofibers regarding the relation between cells and fibrin gel. Immunofluorescent staining of fibrin gel after 6 days of cell seeding and culture demonstrated well expanded and incorporated network of neurons. In addition, viability, proliferation, and neuronal growth of seeded cells were analyzed at days 1, 3, and 6. Comparing those results with 2D culture of seeded cells showed positive effect of 3D culture. Taken together, the results suggest that fibrin can provide a suitable, three-dimensional scaffold for neuronal survival and outgrowth for regeneration of the central nervous system. © 2013 Wiley Periodicals, Inc.

  20. TEST/QA PLAN FOR THE VERIFICATION TESTING OF ALTERNATIVES OR REFORMULATED LIQUID FUELS, FUEL ADDITIVES, FUEL EMULSONS, AND LUBRICANTS FOR HIGHWAY AND NONROAD USE HEAVY DUTY DIESEL ENGINES AND LIGHT DUTY GASOLINE ENGINES AND VEHICLES

    Science.gov (United States)

    The U.S. Environmental Protection Agency established the Environmental Technology Verification Program to accelerate the development and commercialization of improved environmental technology through third party verification and reporting of product performance. Research Triangl...

  1. GENERIC VERIFICATION PROTOCOL FOR DETERMINATION OF EMISSIONS REDUCTIONS OBTAINED BY USE OF ALTERNATIVE OR REFORMULATED LIQUID FUELS, FUEL ADDITIVES, FUEL EMULSIONS AND LUBRICANTS FOR HIGHWAY AND NONROAD USE DISEL ENGINES AND LIGHT DUTY GASOLINE ENGINES AND VEHICLES

    Science.gov (United States)

    This report sets standards by which the emissions reduction provided by fuel and lubricant technologies can be tested and be tested in a comparable way. It is a generic protocol under the Environmental Technology Verification program.

  2. Recombinant human growth hormone secreted from tissue-engineered bioartificial muscle improves left ventricular function in rat with acute myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    RONG Shu-ling; WANG Yong-jin; WANG Xiao-lin; LU Yong-xin; CHANG Chao; WANG Feng-zhi; LIU Qi-yun; LIU Xiang-yang; GAO Yan-zhang; MI Shao-hua

    2009-01-01

    Background Experimental studies and preliminary clinical studies have suggested that growth hormone (GH) treatment may improve cardiovascular parameters in chronic heart failure (CHF). Recombinant human GH (rhGH) has been delivered by a recombinant protein, by plasmid DNA, and by genetically engineered cells with different pharmacokinetic and physiological properties. The present study aimed to examine a new method for delivery of rhGH using genetically modified bioartificial muscles (BAMs), and investigate whether the rhGH delivered by this technique improves left ventricular (LV) function in rats with CHF.Methods Primary skeletal myoblasts were isolated from several Sprague-Dawley (SD) rats, cultured, purified, and retrovirally transduced to synthesize and secrete human rhGH, and tissue-engineered into implantable BAMs. Ligation of the left coronary artery or sham operation was performed. The rats that underwent ligation were randomly assigned to 2 groups: CHF control group (n=6) and CHF treatment group (n=6). The CHF control group received non-rhGH-secreting BAM (GFP-BAMs) transplantation, and the CHF treatment group received rhGH-secreting BAM (GH-BAMs) transplantation. Another group of rats served as the sham operation group, which was also randomly assigned to 2 subgroups: sham control group (n=6) and sham treatment group (n=6). The sham control group underwent GFP-BAM transplantation, and the sham treatment group underwent GH-BAM transplantation. GH-BAMs and GFP-BAMs were implanted subcutaneously into syngeneic rats with ligaUon of the left coronary artery or sham operation was performed. Eight weeks after the treatment,echocardiography was performed, hGH, insulin-like growth factor-1 (IGF-1) and TNF-a levels in rat serum were measured by radioimmunoassay and ELISA, and then the rats were killed and ventricular samples were subjected to immunohistochemistry. Results Primary rat myoblasts were retrovirally transduced to secrete rhGH and tissue-engineered into

  3. Engineering a Cysteine-Free Form of Human Fibroblast Growth Factor-1 for “Second Generation” Therapeutic Application

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Xue; Kumru, Ozan S.; Blaber, Sachiko I.; Middaugh, C. Russell; Li, Ling; Ornitz, David M.; Sutherland, Mason A.; Tenorio, Connie A.; Blaber, Michael (FSU); (WU-MED); (Kansas)

    2016-07-06

    Human fibroblast growth factor-1 (FGF-1) has broad therapeutic potential in regenerative medicine but has undesirable biophysical properties of low thermostability and 3 buried cysteine (Cys) residues (at positions 16, 83, and 117) that interact to promote irreversible protein unfolding under oxidizing conditions. Mutational substitution of such Cys residues eliminates reactive buried thiols but cannot be accomplished simultaneously at all 3 positions without also introducing further substantial instability. The mutational introduction of a novel Cys residue (Ala66Cys) that forms a stabilizing disulfide bond (i.e., cystine) with one of the extant Cys residues (Cys83) effectively eliminates one Cys while increasing overall stability. This increase in stability offsets the associated instability of remaining Cys substitution mutations and permits production of a Cys-free form of FGF-1 (Cys16Ser/Ala66Cys/Cys117Ala) with only minor overall instability. The addition of a further stabilizing mutation (Pro134Ala) creates a Cys-free FGF-1 mutant with essentially wild-type biophysical properties. The elimination of buried free thiols in FGF-1 can substantially increase the protein half-life in cell culture. Here, we show that the effective cell survival/mitogenic functional activity of a fully Cys-free form is also substantially increased and is equivalent to wild-type FGF-1 formulated in the presence of heparin sulfate as a stabilizing agent. The results identify this Cys-free FGF-1 mutant as an advantageous “second generation” form of FGF-1 for therapeutic application.

  4. Investigation into the Impact of Hold Time, Thermal Mechanical Fatigue, Shotpeen, and Retardation on Fatigue Crack Growth in Inconel Dovetail Slots in Jet Engines

    Science.gov (United States)

    Joiner, Josiah W.

    2011-12-01

    Current jet engine industry studies are ongoing to develop a generic Inconel dovetail slot test case that will be used for calibrating a manufacturing-induced surface damage anomaly distribution curve for future probabilistic life assessments. The stress and temperature profile during the mission have been defined. This analysis will consist of a design of experiments on the Inconel dovetail slot test data. The test case includes thermal and mechanical stresses, as well as variations in hold time, stress and temperature regimes. Several DOEs will be created and run to help assess the impact of four crack growth mechanisms on the damage tolerance life for the different mission profiles: hold time, thermal mechanical fatigue, shotpeen, and retardation. For the sake of this study a parametric study is considered to be a DOE. Calculations will be completed for both surface and corner cracks. For surface cracks, a 2:1 aspect ratio semicircular initial flaw size of 15 x 30 mils will be used. For corner cracks, a 1:1 aspect ratio semicircular initial flaw size of 15 x 15 mils will be used. The calculations will be completed using a proprietary crack propagation code. The results of this study will reveal the mission profile at which each of the aforementioned effects begins to have a significant impact on the damage tolerance life. These studies are critical to ensuring the final test case adequately addresses each of these critical crack propagation drivers.

  5. Engineering Encounters: Engineering Adaptations

    Science.gov (United States)

    Gatling, Anne; Vaughn, Meredith Houle

    2015-01-01

    Engineering is not a subject that has historically been taught in elementary schools, but with the emphasis on engineering in the "Next Generation Science Standards," curricula are being developed to explicitly teach engineering content and design. However, many of the scientific investigations already conducted with students have…

  6. Engineering Encounters: Engineering Adaptations

    Science.gov (United States)

    Gatling, Anne; Vaughn, Meredith Houle

    2015-01-01

    Engineering is not a subject that has historically been taught in elementary schools, but with the emphasis on engineering in the "Next Generation Science Standards," curricula are being developed to explicitly teach engineering content and design. However, many of the scientific investigations already conducted with students have…

  7. Development of the methodology of exhaust emissions measurement under RDE (Real Driving Emissions) conditions for non-road mobile machinery (NRMM) vehicles

    Science.gov (United States)

    Merkisz, J.; Lijewski, P.; Fuc, P.; Siedlecki, M.; Ziolkowski, A.

    2016-09-01

    The paper analyzes the exhaust emissions from farm vehicles based on research performed under field conditions (RDE) according to the NTE procedure. This analysis has shown that it is hard to meet the NTE requirements under field conditions (engine operation in the NTE zone for at least 30 seconds). Due to a very high variability of the engine conditions, the share of a valid number of NTE windows in the field test is small throughout the entire test. For this reason, a modification of the measurement and exhaust emissions calculation methodology has been proposed for farm vehicles of the NRMM group. A test has been developed composed of the following phases: trip to the operation site (paved roads) and field operations (including u-turns and maneuvering). The range of the operation time share in individual test phases has been determined. A change in the method of calculating the real exhaust emissions has also been implemented in relation to the NTE procedure.

  8. Engines of Growth and Innovation

    Institute of Scientific and Technical Information of China (English)

    DING WENLEI

    2010-01-01

    @@ It's a catchphrase you often hear in Shenzhen among the business elite."Beijing and Shanghai may be the top choices for multinationals,but Shenzhen is the paradise for innovative startups with Chinese origins,"said Yang Ting,Vice President of Mindray,a company that embodies that message.

  9. Identifying the ionically bound cell wall and intracellular glycoside hydrolases in late growth stage Arabidopsis stems: implications for the genetic engineering of bioenergy crops

    Directory of Open Access Journals (Sweden)

    Hui eWEI

    2015-05-01

    Full Text Available Identifying the cell wall-ionically bound glycoside hydrolases (GHs in Arabidopsis stems is important for understanding the regulation of cell wall integrity. For cell wall proteomics studies, the preparation of clean cell wall fractions is a challenge since cell walls constitute an open compartment, which is more likely to contain a mixture of intracellular and extracellular proteins due to cell leakage at the late growth stage. Here, we utilize a CaCl2-extraction procedure to isolate non-structural proteins from Arabidopsis whole stems, followed by the in-solution and in-gel digestion methods coupled with Nano-LC-MS/MS, bioinformatics and literature analyses. This has led to the identification of 75 proteins identified using the in-solution method and 236 proteins identified by the in-gel method, among which about 10% of proteins predicted to be secreted. Together, eight cell wall proteins, namely AT1G75040, AT5G26000, AT3G57260, AT4G21650, AT3G52960, AT3G49120, AT5G49360 and AT3G14067, were identified by the in-solution method; among them, three were the GHs (AT5G26000, myrosinase 1, GH1; AT3G57260, β-1,3-glucanase 2, GH17; AT5G49360, bifunctional XYL 1/α-L-arabinofuranosidase, GH3. Moreover, four more GHs: AT4G30270 (xyloglucan endotransferase, GH16, AT1G68560 (bifunctional α-l-arabinofuranosidase/XYL, GH31, AT1G12240 (invertase, GH32 and AT2G28470 (β-galactosidase 8, GH35, were identified by the in-gel solution method only. Notably, more than half of above identified GHs are xylan- or hemicellulose-modifying enzymes, and will likely have an impact on cellulose accessibility, which is a critical factor for downstream enzymatic hydrolysis of plant tissues for biofuels production. The implications of these cell wall proteins identified at the late growth stage for the genetic engineering of bioenergy crops are discussed.

  10. Engineering Encounters: Reverse Engineering

    Science.gov (United States)

    McGowan, Veronica Cassone; Ventura, Marcia; Bell, Philip

    2017-01-01

    This column presents ideas and techniques to enhance your science teaching. This month's issue shares information on how students' everyday experiences can support science learning through engineering design. In this article, the authors outline a reverse-engineering model of instruction and describe one example of how it looked in our fifth-grade…

  11. SYSTEMS ENGINEERING RESEARCH

    Institute of Scientific and Technical Information of China (English)

    Abd-El-Kader SAHRAOUI; Dennis M. BUEDE; Andrew P. SAGE

    2008-01-01

    In this paper, we propose selected research topics that are believed central to progress and growth in the application of systems engineering (SE). As a professional activity, and as an intellectual activity, systems engineering has strong links to such associated disciplines as decision analysis, operation research, project management, quality management, and systems design. When focussing on systems engineering research, we should distinguish between subjects that are of systems engineering essence and others that more closely correspond to those that are more relevant for related disciplines.

  12. Insulin, ascorbate, and glucose have a much greater influence than transferrin and selenous acid on the in vitro growth of engineered cartilage in chondrogenic media.

    Science.gov (United States)

    Cigan, Alexander D; Nims, Robert J; Albro, Michael B; Esau, John D; Dreyer, Marissa P; Vunjak-Novakovic, Gordana; Hung, Clark T; Ateshian, Gerard A

    2013-09-01

    The primary goal of this study was to characterize the response of chondrocyte-seeded agarose constructs to varying concentrations of several key nutrients in a chondrogenic medium, within the overall context of optimizing the key nutrients and the placement of nutrient channels for successful growth of cartilage tissue constructs large enough to be clinically relevant in the treatment of osteoarthritis (OA). To this end, chondrocyte-agarose constructs (ø4×2.34 mm, 30×10(6) cells/mL) were subjected to varying supplementation levels of insulin (0× to 30× relative to standard supplementation), transferrin (0× to 30×), selenous acid (0× to 10×), ascorbate (0× to 30×), and glucose (0× to 3×). The quality of resulting engineered tissue constructs was evaluated by their compressive modulus (E(-Y)), tensile modulus (E(+Y)), hydraulic permeability (k), and content of sulfated glycosaminoglycans (sGAG) and collagen (COL); DNA content was also quantified. Three control groups from two separate castings of constructs (1× concentrations of all medium constituents) were used. After 42 days of culture, values in each of these controls were, respectively, E(-Y)=518±78, 401±113, 236±67 kPa; E(+Y)=1420±430, 1140±490, 1240±280 kPa; k=2.3±0.8×10(-3), 5.4±7.0×10(-3), 3.3±1.3×10(-3) mm(4)/N·s; sGAG=7.8±0.3, 6.3±0.4, 4.1±0.5%/ww; COL=1.3±0.2, 1.1±0.3, 1.4±0.4%/ww; and DNA=11.5±2.2, 12.1±0.6, 5.2±2.8 μg/disk. The presence of insulin and ascorbate was essential, but their concentrations may drop as low as 0.3× without detrimental effects on any of the measured properties; excessive supplementation of ascorbate (up to 30×) was detrimental to E(-Y), and 30× insulin was detrimental to both E(+Y) and E(-Y). The presence of glucose was similarly essential, and matrix elaboration was significantly dependent on its concentration (p<10(-6)), with loss of functional properties, composition, and cellularity observed at ≤0.3×; excessive glucose

  13. Diesel Engine performance improvement in a 1-D engine model using Particle Swarm Optimization

    Science.gov (United States)

    Karra, Prashanth

    2015-12-01

    A particle swarm optimization (PSO) technique was implemented to improve the engine development and optimization process to simultaneously reduce emissions and improve the fuel efficiency. The optimization was performed on a 4-stroke 4-cylinder GT-Power based 1-D diesel engine model. To achieve the multi-objective optimization, a merit function was defined which included the parameters to be optimized: Nitrogen Oxides (NOx), Nonmethyl hydro carbons (NMHC), Carbon Monoxide (CO), Brake Specific Fuel Consumption (BSFC). EPA Tier 3 emissions standards for non-road diesel engines between 37 and 75 kW of output were chosen as targets for the optimization. The combustion parameters analyzed in this study include: Start of main Injection, Start of Pilot Injection, Pilot fuel quantity, Swirl, and Tumble. The PSO was found to be very effective in quickly arriving at a solution that met the target criteria as defined in the merit function. The optimization took around 40-50 runs to find the most favourable engine operating condition under the constraints specified in the optimization. In a favourable case with a high merit function values, the NOx+NMHC and CO values were reduced to as low as 2.9 and 0.014 g/kWh, respectively. The operating conditions at this point were: 10 ATDC Main SOI, -25 ATDC Pilot SOI, 0.25 mg of pilot fuel, 0.45 Swirl and 0.85 tumble. These results indicate that late main injections preceded by a close, small pilot injection are most favourable conditions at the operating condition tested.

  14. 构建“卓越工程师教育培养计划”实施保障体系%Establishing Guarantee System for ″Excellent Engineer Growth Plan″

    Institute of Scientific and Technical Information of China (English)

    顾嘉; 张航; 唐永升

    2012-01-01

    "卓越工程师教育培养计划"旨在培养造就一批适应经济社会发展需要的高质量工程人才。高校要紧紧把握这一战略契机,要在专业遴选、培养模式、培养目标和培养方案等诸多方面构建起一整套能有效保障"卓越计划"实施的体系,统筹人才培养各领域的诸多关系;同时还要建立健全各项协调机制,不断完善工程人才培养体系。进一步深化改革,积极探索培养"卓越工程师"的方法和规律,努力造就创新型工程人才。%″Excellent engineer growth plan″ aims at fostering a batch of high-quality engineers to meet the needs of social and economic development.Colleges should take this strategic opportunity to establish a system that can effectively guarantee the implementation of ″excellent engineer growth plan″ in terms of major selection,fostering mode,fostering objective and fostering plan.In the mean time,a mechanism should be established to improve the engineer fostering system on the continuous basis.The colleges should push forward the reform,actively explore the methods and rules of fostering excellent engineers so as to cultivate talents with creative nature.

  15. L-arginine and arginine ethyl ester enhance proliferation of endothelial cells and preadipocytes - how an arginine ethyl ester-releasing biomaterial could support endothelial cell growth in tissue engineering.

    Science.gov (United States)

    Paul, N E; Lösel, R; Hemmrich, K; Goy, D; Pallua, N; Klee, D

    2015-01-01

    Adipose tissue engineering is a promising solution for the reconstruction of soft tissue defects. An insufficient neovascularisation within the scaffolds that leads to necrosis and tissue loss is still a major shortcoming of current tissue engineering attempts. Biomaterials, which release angiogenic factors such as L-arginine, could overcome this challenge by supporting the neovascularisation of the constructs. L-arginine is insoluble in organic solvents and thus cannot be incorporated into commonly used polymers in contrast to its ethyl ester. Here, we compared the effects of arginine and its ethyl ester on endothelial cells and preadipocytes, and generated an arginine ethyl ester-releasing, angiogenic polymer. We cultivated adipose tissue-derived endothelial cells and preadipocytes in arginine-free medium supplemented with L-arginine or L-arginine ethyl ester and assayed the proliferation rate and the degree of adipogenic differentiation, respectively. Additionally, we prepared arginine ethyl ester-releasing poly(D,L-lactide) foils, and investigated their impact on endothelial cell proliferation. We could demonstrate that arginine ethyl ester like arginine significantly increased the proliferation of endothelial cells and preadipocytes without inhibiting an induced adipogenic conversion of the preadipocytes. Further, we could show that the arginine ethyl ester-releasing polymer significantly increased endothelial cell growth. The present data are helpful guidance for generating angiogenic biomaterials that promote endothelial cell growth, and thereby could support neovascularisation within tissue engineering approaches.

  16. Layered Systems Engineering Engines

    Science.gov (United States)

    Breidenthal, Julian C.; Overman, Marvin J.

    2009-01-01

    A notation is described for depicting the relationships between multiple, contemporaneous systems engineering efforts undertaken within a multi-layer system-of-systems hierarchy. We combined the concepts of remoteness of activity from the end customer, depiction of activity on a timeline, and data flow to create a new kind of diagram which we call a "Layered Vee Diagram." This notation is an advance over previous notations because it is able to be simultaneously precise about activity, level of granularity, product exchanges, and timing; these advances provide systems engineering managers a significantly improved ability to express and understand the relationships between many systems engineering efforts. Using the new notation, we obtain a key insight into the relationship between project duration and the strategy selected for chaining the systems engineering effort between layers, as well as insights into the costs, opportunities, and risks associated with alternate chaining strategies.

  17. Engineer Ethics

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Dae Sik; Kim, Yeong Pil; Kim, Yeong Jin

    2003-03-15

    This book tells of engineer ethics such as basic understanding of engineer ethics with history of engineering as a occupation, definition of engineering and specialized job and engineering, engineer ethics as professional ethics, general principles of ethics and its limitation, ethical theory and application, technique to solve the ethical problems, responsibility, safety and danger, information engineer ethics, biotechnological ethics like artificial insemination, life reproduction, gene therapy and environmental ethics.

  18. Four Engineers...

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    There are four engineers traveling in a car;a mechanical engineer,a chemical engi-neer,an electrical engineer and a comput-er engineer.The car breaks down.“Sounds to me as if the pistons have seized.We ll have to strip down the engine before we canget the car working again,”says the mechanical

  19. Turning Engineering Green

    DEFF Research Database (Denmark)

    Jamison, Andrew

    2012-01-01

    Since the 1970s, the relations between engineering and development have changed significantly. On the one hand, at a discursive or macro level, there has been a shift in regard to the kind of development to which engineering is meant to contribute, from furthering economic growth to an approach...... to development that is “sustainable” in one way or another. On the other hand, on a practitioner, or micro level, there has been a change in the kinds of competence that engineers are expected to have in order to be able to contribute to development, due to the emergence of new fields of “technoscience” blurring...... the boundaries between what was previously considered science and what was previously considered technology. Finally, in between, at an institutional or meso level, there have been significant changes in how engineering work and engineering education are organized. This chapter attempts to provide an overview...

  20. Evaporation temperature-tuned physical vapor deposition growth engineering of one-dimensional non-Fermi liquid tetrathiofulvalene tetracyanoquinodimethane thin films

    DEFF Research Database (Denmark)

    Sarkar, I.; Laux, M.; Demokritova, J.

    2010-01-01

    We describe the growth of high quality tetrathiofulvalene tetracyanoquinodimethane (TTF-TCNQ) organic charge-transfer thin films which show a clear non-Fermi liquid behavior. Temperature dependent angle resolved photoemission spectroscopy and electronic structure calculations show that the growth...... of TTF-TCNQ films is accompanied by the unfavorable presence of neutral TTF and TCNQ molecules. The quality of the films can be controlled by tuning the evaporation temperature of the precursor in physical vapor deposition method....

  1. Potential in two types of collagen scaffolds for urological tissue engineering applications - Are there differences in growth behaviour of juvenile and adult vesical cells?

    Science.gov (United States)

    Leonhäuser, D; Vogt, M; Tolba, R H; Grosse, J O

    2016-02-01

    The aging society has a deep impact on patient care in urology. The number of patients in need of partial or whole bladder wall replacement is increasing simultaneously with the number of cancer incidents. Therefore, urological research requires a model of bladder wall replacement in adult and elderly people. Two types of porcine collagen I/III scaffolds were used in vitro for comparison of cell growth of two different pig breeds at different growth stages. Scaffolds were characterised with scanning electron and laser scanning microscopy. Urothelial and detrusor smooth muscle cells were isolated from 15 adult Göttingen minipigs and 15 juvenile German Landrace pigs. Growth behaviour was examined in cell culture and seeded onto the collagen scaffolds via immunohistochemistry, two-photon laser scanning microscopy and a viability assay. The collagen scaffolds showed different structured surfaces which are appropriate for seeding of the two different cell types. Moisturisation of the scaffolds resulted in a change of the structure. Cell growth of German Landrace urothelial cells and smooth muscle cells was significantly higher than cell growth of the Göttingen minipig cells. Seeding of scaffolds with both cell types from both pig races was possible which could be shown by immunohistochemistry and two-photon laser scanning microscopy. Growth behaviour on the scaffolds was significantly increased for the German Landrace compared to Göttingen minipig. Nevertheless, seeding with the adult Göttingen minipig cells resulted in a closed layer on the surface and urothelial cells and smooth muscle cells showed increasing growth until day 14. The results show that these collagen scaffolds are adequate for the seeding with vesical cells. Moreover, they seem appropriate for the use as an in vitro model for the adult or elderly as the cells of the adult Göttingen minipig too, show good growth behaviour. © The Author(s) 2015.

  2. Engineering ceramics

    CERN Document Server

    Bengisu, Murat

    2001-01-01

    This is a comprehensive book applying especially to junior and senior engineering students pursuing Materials Science/ Engineering, Ceramic Engineering and Mechanical Engineering degrees. It is also a reference book for other disciplines such as Chemical Engineering, Biomedical Engineering, Nuclear Engineering and Environmental Engineering. Important properties of most engineering ceramics are given in detailed tables. Many current and possible applications of engineering ceramics are described, which can be used as a guide for materials selection and for potential future research. While covering all relevant information regarding raw materials, processing properties, characterization and applications of engineering ceramics, the book also summarizes most recent innovations and developments in this field as a result of extensive literature search.

  3. Engineering and Software Engineering

    Science.gov (United States)

    Jackson, Michael

    The phrase ‘software engineering' has many meanings. One central meaning is the reliable development of dependable computer-based systems, especially those for critical applications. This is not a solved problem. Failures in software development have played a large part in many fatalities and in huge economic losses. While some of these failures may be attributable to programming errors in the narrowest sense—a program's failure to satisfy a given formal specification—there is good reason to think that most of them have other roots. These roots are located in the problem of software engineering rather than in the problem of program correctness. The famous 1968 conference was motivated by the belief that software development should be based on “the types of theoretical foundations and practical disciplines that are traditional in the established branches of engineering.” Yet after forty years of currency the phrase ‘software engineering' still denotes no more than a vague and largely unfulfilled aspiration. Two major causes of this disappointment are immediately clear. First, too many areas of software development are inadequately specialised, and consequently have not developed the repertoires of normal designs that are the indispensable basis of reliable engineering success. Second, the relationship between structural design and formal analytical techniques for software has rarely been one of fruitful synergy: too often it has defined a boundary between competing dogmas, at which mutual distrust and incomprehension deprive both sides of advantages that should be within their grasp. This paper discusses these causes and their effects. Whether the common practice of software development will eventually satisfy the broad aspiration of 1968 is hard to predict; but an understanding of past failure is surely a prerequisite of future success.

  4. Mechanical engineering

    CERN Document Server

    Darbyshire, Alan

    2010-01-01

    Alan Darbyshire's best-selling text book provides five-star high quality content to a potential audience of 13,000 engineering students. It explains the most popular specialist units of the Mechanical Engineering, Manufacturing Engineering and Operations & Maintenance Engineering pathways of the new 2010 BTEC National Engineering syllabus. This challenging textbook also features contributions from specialist lecturers, ensuring that no stone is left unturned.

  5. Engineering the Rhizosphere.

    Science.gov (United States)

    Dessaux, Yves; Grandclément, Catherine; Faure, Denis

    2016-03-01

    All components of the rhizosphere can be engineered to promote plant health and growth, two features that strongly depend upon the interactions of living organisms with their environment. This review describes the progress in plant and microbial molecular genetics and ecology that has led to a wealth of potential applications. Recent efforts especially deal with the plant defense machinery that is instrumental in engineering plant resistance to biotic stresses. Another approach involves microbial population engineering rather than single strain engineering. More generally, the plants (and the associated microbes) are no longer seen as 'individual' but rather as a holobiont, in other words a unit of selection in evolution, a concept that holds great promise for future plant breeding programs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. A Library of Infectious Hepatitis C Viruses with Engineered Mutations in the E2 Gene Reveals Growth-Adaptive Mutations That Modulate Interactions with Scavenger Receptor Class B Type I.

    Science.gov (United States)

    Zuiani, Adam; Chen, Kevin; Schwarz, Megan C; White, James P; Luca, Vincent C; Fremont, Daved H; Wang, David; Evans, Matthew J; Diamond, Michael S

    2016-12-01

    While natural hepatitis C virus (HCV) infection results in highly diverse quasispecies of related viruses over time, mutations accumulate more slowly in tissue culture, in part because of the inefficiency of replication in cells. To create a highly diverse population of HCV particles in cell culture and identify novel growth-enhancing mutations, we engineered a library of infectious HCV with all codons represented at most positions in the ectodomain of the E2 gene. We identified many putative growth-adaptive mutations and selected nine highly represented E2 mutants for further study: Q412R, T416R, S449P, T563V, A579R, L619T, V626S, K632T, and L644I. We evaluated these mutants for changes in particle-to-infectious-unit ratio, sensitivity to neutralizing antibody or CD81 large extracellular loop (CD81-LEL) inhibition, entry factor usage, and buoyant density profiles. Q412R, T416R, S449P, T563V, and L619T were neutralized more efficiently by anti-E2 antibodies and T416R, T563V, and L619T by CD81-LEL. Remarkably, all nine variants showed reduced dependence on scavenger receptor class B type I (SR-BI) for infection. This shift from SR-BI usage did not correlate with a change in the buoyant density profiles of the variants, suggesting an altered E2-SR-BI interaction rather than changes in the virus-associated lipoprotein-E2 interaction. Our results demonstrate that residues influencing SR-BI usage are distributed across E2 and support the development of large-scale mutagenesis studies to identify viral variants with unique functional properties. Characterizing variant viruses can reveal new information about the life cycle of HCV and the roles played by different viral genes. However, it is difficult to recapitulate high levels of diversity in the laboratory because of limitations in the HCV culture system. To overcome this limitation, we engineered a library of mutations into the E2 gene in the context of an infectious clone of the virus. We used this library of viruses

  7. Engineering Cartilage

    Science.gov (United States)

    ... Research Matters NIH Research Matters March 3, 2014 Engineering Cartilage Artistic rendering of human stem cells on ... situations has been a major goal in tissue engineering. Cartilage contains water, collagen, proteoglycans, and chondrocytes. Collagens ...

  8. Industrial Engineering

    DEFF Research Database (Denmark)

    Karlsson, Christer

    2015-01-01

    Industrial engineering is a discipline that is concerned with increasing the effectiveness of (primarily) manufacturing and (occasionally).......Industrial engineering is a discipline that is concerned with increasing the effectiveness of (primarily) manufacturing and (occasionally)....

  9. Governing Engineering

    DEFF Research Database (Denmark)

    Buch, Anders

    2011-01-01

    Abstract: Most people agree that our world faces daunting problems and, correctly or not, technological solutions are seen as an integral part of an overall solution. But what exactly are the problems and how does the engineering ‘mind set’ frame these problems? This chapter sets out to unravel...... dominant perspectives in challenge perception in engineering in the US and Denmark. Challenge perception and response strategies are closely linked through discursive practices. Challenge perceptions within the engineering community and the surrounding society are thus critical for the shaping...... of engineering education and the engineering profession. Through an analysis of influential reports and position papers on engineering and engineering education the chapter sets out to identify how engineering is problematized and eventually governed. Drawing on insights from governmentality studies the chapter...

  10. Governing Engineering

    DEFF Research Database (Denmark)

    Buch, Anders

    2012-01-01

    Most people agree that our world face daunting problems and, correctly or not, technological solutions are seen as an integral part of an overall solution. But what exactly are the problems and how does the engineering ‘mind set’ frame these problems? This chapter sets out to unravel dominant...... perspectives in challenge per-ception in engineering in the US and Denmark. Challenge perception and response strategies are closely linked through discursive practices. Challenge perceptions within the engineering community and the surrounding society are thus critical for the shaping of engineering education...... and the engineering profession. Through an analysis of influential reports and position papers on engineering and engineering education the chapter sets out to identify how engineering is problematized and eventually governed. Drawing on insights from governmentality studies the chapter strives to elicit the bodies...

  11. Computer Engineers.

    Science.gov (United States)

    Moncarz, Roger

    2000-01-01

    Looks at computer engineers and describes their job, employment outlook, earnings, and training and qualifications. Provides a list of resources related to computer engineering careers and the computer industry. (JOW)

  12. Biochemical Engineering.

    Science.gov (United States)

    Dunnill, P.

    1979-01-01

    Biochemical engineering as a scientific discipline is becoming accepted in England and is drawing many young men and women to its ranks. This article focuses on how engineering came to embrace the biological sciences. (Author/SA)

  13. Engineering _ litteraturliste

    DEFF Research Database (Denmark)

    Sillasen, Martin Krabbe; Daugbjerg, Peer; Nielsen, Keld

    2017-01-01

    Litteraturliste udarbejdet som grundlag for artiklen ”Engineering – svaret på naturfagenes udfordringer?”......Litteraturliste udarbejdet som grundlag for artiklen ”Engineering – svaret på naturfagenes udfordringer?”...

  14. Prosthetic Engineering

    Science.gov (United States)

    ... Overview CoE for Limb Loss Prevention and Prosthetic Engineering Menu Menu VA Center of Excellence for Limb ... ZIP code here Enter ZIP code here Prosthetic Engineering - Overview Our aim is to improve prosthetic prescription ...

  15. Growth and interface engineering in thin-film Ba0.6Sr0.4TiO3 /SrMoO3 heterostructures

    Science.gov (United States)

    Radetinac, Aldin; Ziegler, Jürgen; Vafaee, Mehran; Alff, Lambert; Komissinskiy, Philipp

    2017-04-01

    Epitaxial heterostructures of ferroelectric Ba0.6Sr0.4TiO3 and highly conducting SrMoO3 were grown by pulsed laser deposition on SrTiO3 (0 0 1) substrates. Surface oxidation of the SrMoO3 film is suppressed using a thin cap interlayer of Ba0.6Sr0.4TiO3-δ grown in reduced atmosphere. As shown by X-ray photoelectron spectroscopy, the Mo4+ valence state of the SrMoO3 films is stable upon annealing of the sample in oxygen up to 600 °C. The described oxygen interface engineering enables utilization of the highly conducting material SrMoO3 in multilayer oxide ferroelectric varactors.

  16. Engineering Motion

    Science.gov (United States)

    Tuttle, Nicole; Stanley, Wendy; Bieniek, Tracy

    2016-01-01

    For many teachers, engineering can be intimidating; teachers receive little training in engineering, particularly those teaching early elementary students. In addition, the necessity of differentiating for students with special needs can make engineering more challenging to teach. This article describes a professional development program…

  17. Engineering Motion

    Science.gov (United States)

    Tuttle, Nicole; Stanley, Wendy; Bieniek, Tracy

    2016-01-01

    For many teachers, engineering can be intimidating; teachers receive little training in engineering, particularly those teaching early elementary students. In addition, the necessity of differentiating for students with special needs can make engineering more challenging to teach. This article describes a professional development program…

  18. 40 CFR 80.521 - What are the standards and identification requirements for diesel fuel additives?

    Science.gov (United States)

    2010-07-01

    ... Motor Vehicle Diesel Fuel; Nonroad, Locomotive, and Marine Diesel Fuel; and ECA Marine Fuel Motor... consumer in diesel motor vehicles or nonroad diesel engines. ... identification requirements for diesel fuel additives? 80.521 Section 80.521 Protection of...

  19. 40 CFR 49.130 - Rule for limiting sulfur in fuels.

    Science.gov (United States)

    2010-07-01

    ... section? This section does not apply to gasoline and diesel fuel, such as automotive and marine diesel..., gaseous fuel, marine vessel, mobile sources, motor vehicle, nonroad engine, nonroad vehicle, owner...

  20. 血管内皮生长因子和骨形态发生蛋白在骨组织工程中的作用%Vascular endothelial growth factor and bone morphogenetic protein in the bone tissue engineering

    Institute of Scientific and Technical Information of China (English)

    纪经涛; 胡永成; 夏群; 苗军; 陈晓鹏; 方程

    2015-01-01

    and progressive bone disorder are very common, and bone tissue engineering provides a new approach to bone defect repair. Growth factors related to bone tissue engineering bone have been reported a lot and have achieved some results. How to mimick the natural timing of different growth factors with different bioactivities has become the current hotspot in bone repair. OBJECTIVE: To review the new developments in vascular endothelial growth factor and bone morphogenetic protein in bone tissue engineering. METHODS: The first author searched CNKI (1990/2015) and Medline database (1990/2015) for related articles using the key words of “osteogenic factors, angiogenic factors, tissue engineering bone, bone repair, vascularization, vascular endothelial growth factor, bone morphogenetic protein, sequential release, seed cels, cytoskeleton” in Chinese and English, respectively. Mechanism of action and research direction about vascular endothelial growth factor and bone morphogenetic protein were summarized. RESULTS AND CONCLUSION:Totaly 313 papers were searched initialy, and finaly 87 papers were enroled in result analysis. The results show that different growth factors play different roles in bone repair. Vascularization and osteogenesis are the most important processes in bone repair. The osteogenic factors play an important role in maintaining bone structure and bone formation. The angiogenic factors can provide oxygen and nutrients for tissue growth, differentiation and functionalization. The combination of osteogenic and angiogenic factors has a better osteogenic effect than osteogenic or angiogenic factors used alone. However, the most important problem is how to control the exogenous osteogenesis and the release dosage of angiogenic factors in bone repair.

  1. Computational engineering

    CERN Document Server

    2014-01-01

    The book presents state-of-the-art works in computational engineering. Focus is on mathematical modeling, numerical simulation, experimental validation and visualization in engineering sciences. In particular, the following topics are presented: constitutive models and their implementation into finite element codes, numerical models in nonlinear elasto-dynamics including seismic excitations, multiphase models in structural engineering and multiscale models of materials systems, sensitivity and reliability analysis of engineering structures, the application of scientific computing in urban water management and hydraulic engineering, and the application of genetic algorithms for the registration of laser scanner point clouds.

  2. Chondrogenic induction of mesenchymal stromal/stem cells from Wharton's jelly embedded in alginate hydrogel and without added growth factor: an alternative stem cell source for cartilage tissue engineering.

    Science.gov (United States)

    Reppel, Loïc; Schiavi, Jessica; Charif, Naceur; Leger, Léonore; Yu, Hao; Pinzano, Astrid; Henrionnet, Christel; Stoltz, Jean-François; Bensoussan, Danièle; Huselstein, Céline

    2015-12-30

    Due to their intrinsic properties, stem cells are promising tools for new developments in tissue engineering and particularly for cartilage tissue regeneration. Although mesenchymal stromal/stem cells from bone marrow (BM-MSC) have long been the most used stem cell source in cartilage tissue engineering, they have certain limits. Thanks to their properties such as low immunogenicity and particularly chondrogenic differentiation potential, mesenchymal stromal/stem cells from Wharton's jelly (WJ-MSC) promise to be an interesting source of MSC for cartilage tissue engineering. In this study, we propose to evaluate chondrogenic potential of WJ-MSC embedded in alginate/hyaluronic acid hydrogel over 28 days. Hydrogels were constructed by the original spraying method. Our main objective was to evaluate chondrogenic differentiation of WJ-MSC on three-dimensional scaffolds, without adding growth factors, at transcript and protein levels. We compared the results to those obtained from standard BM-MSC. After 3 days of culture, WJ-MSC seemed to be adapted to their new three-dimensional environment without any detectable damage. From day 14 and up to 28 days, the proportion of WJ-MSC CD73(+), CD90(+), CD105(+) and CD166(+) decreased significantly compared to monolayer marker expression. Moreover, WJ-MSC and BM-MSC showed different phenotype profiles. After 28 days of scaffold culture, our results showed strong upregulation of cartilage-specific transcript expression. WJ-MSC exhibited greater type II collagen synthesis than BM-MSC at both transcript and protein levels. Furthermore, our work highlighted a relevant result showing that WJ-MSC expressed Runx2 and type X collagen at lower levels than BM-MSC. Once seeded in the hydrogel scaffold, WJ-MSC and BM-MSC have different profiles of chondrogenic differentiation at both the phenotypic level and matrix synthesis. After 4 weeks, WJ-MSC, embedded in a three-dimensional environment, were able to adapt to their environment and

  3. Resorbable polymeric scaffolds for bone tissue engineering: the influence of their microstructure on the growth of human osteoblast-like MG 63 cells.

    Science.gov (United States)

    Pamula, Elzbieta; Filová, Elena; Bacáková, Lucie; Lisá, Vera; Adamczyk, Daniel

    2009-05-01

    Degradable three-dimensional porous scaffolds applicable as cell carriers for bone tissue engineering were developed by an innovative solvent casting/particulate leaching technique from poly(L-lactide-co-glycolide) (PLG). Three types of PLG scaffolds were prepared, and these had the same high porosity (83%) but increasing diameter of the pores (180-200 microm, 250-320 microm, and 400-600 microm) and increasing pore interconnectivity. The colonization of the scaffolds with human osteoblast-like MG 63 cells was then studied in vitro in a conventional static cell culture system. The number of cells growing on the scaffolds on days 1 and 7 after seeding was highest in the material with the largest pore diameter, but on day 15, the differences among the scaffolds disappeared. Confocal microscopy revealed that on day 1 after seeding, the cells penetrated to a depth of 490 +/- 100 microm, 720 +/- 170 microm, and 720 +/- 120 microm into the scaffolds of small, medium, and large pore size, respectively. Incorporation of bromodeoxyuridine into newly synthesized DNA and the concentration of vinculin, beta-actin, osteopontin, and osteocalcin in cells on the scaffolds of all pore sizes were similar to the values obtained on standard tissue culture polystyrene, which indicated good biocompatibility of the scaffolds. These results suggest that all scaffolds could serve as good carriers for bone cells, although the quickest colonization with cells was found in the scaffolds with the largest pore diameter from 400 to 600 microm.

  4. Efficient generation of smooth muscle cells from adipose-derived stromal cells by 3D mechanical stimulation can substitute the use of growth factors in vascular tissue engineering.

    Science.gov (United States)

    Parvizi, Mojtaba; Bolhuis-Versteeg, Lydia A M; Poot, André A; Harmsen, Martin C

    2016-07-01

    Occluding artery disease causes a high demand for bioartificial replacement vessels. We investigated the combined use of biodegradable and creep-free poly (1,3-trimethylene carbonate) (PTMC) with smooth muscle cells (SMC) derived by biochemical or mechanical stimulation of adipose tissue-derived stromal cells (ASC) to engineer bioartificial arteries. Biochemical induction of cultured ASC to SMC was done with TGF-β1 for 7d. Phenotype and function were assessed by qRT-PCR, immunodetection and collagen contraction assays. The influence of mechanical stimulation on non-differentiated and pre-differentiated ASC, loaded in porous tubular PTMC scaffolds, was assessed after culturing under pulsatile flow for 14d. Assays included qRT-PCR, production of extracellular matrix and scanning electron microscopy. ASC adhesion and TGF-β1-driven differentiation to contractile SMC on PTMC did not differ from tissue culture polystyrene controls. Mesenchymal and SMC markers were increased compared to controls. Interestingly, pre-differentiated ASC had only marginal higher contractility than controls. Moreover, in 3D PTMC scaffolds, mechanical stimulation yielded well-aligned ASC-derived SMC which deposited ECM. Under the same conditions, pre-differentiated ASC-derived SMC maintained their SMC phenotype. Our results show that mechanical stimulation can replace TGF-β1 pre-stimulation to generate SMC from ASC and that pre-differentiated ASC keep their SMC phenotype with increased expression of SMC markers.

  5. Advanced computational approaches to biomedical engineering

    CERN Document Server

    Saha, Punam K; Basu, Subhadip

    2014-01-01

    There has been rapid growth in biomedical engineering in recent decades, given advancements in medical imaging and physiological modelling and sensing systems, coupled with immense growth in computational and network technology, analytic approaches, visualization and virtual-reality, man-machine interaction and automation. Biomedical engineering involves applying engineering principles to the medical and biological sciences and it comprises several topics including biomedicine, medical imaging, physiological modelling and sensing, instrumentation, real-time systems, automation and control, sig

  6. Global Software Engineering

    DEFF Research Database (Denmark)

    Ebert, Christof; Kuhrmann, Marco; Prikladnicki, Rafael

    2016-01-01

    SOFTWARE, LIKE ALL industry products, is the result of complex multinational supply chains with many partners from concept to development to production and maintenance. Global software engineering (GSE), IT outsourcing, and business process outsourcing during the past decade have showed growth...... rates of 10 to 20 percent per year. This instalment of Practitioner’s Digest summarizes experiences and guidance from industry to facilitate knowledge and technology transfer for GSE. It’s based on industry feedback from the annual IEEE International Conference on Global Software Engineering, which had...

  7. Prevention of experimental autoimmune encephalomyelitis in DA rats by grafting primary skin fibroblasts engineered to express transforming growth factor-beta1.

    Science.gov (United States)

    Zargarova, T; Kulakova, O; Prassolov, V; Zharmukhamedova, T; Tsyganova, V; Turobov, V; Ivanov, D; Parfenov, M; Sudomoina, M; Chernajovsky, Y; Favorova, O

    2004-08-01

    To determine whether primary fibroblasts producing latent transforming growth factor beta1 (TGF-beta1) are capable of down-regulating experimental autoimmune encephalomyelitis (EAE), a retroviral vector TGF-beta1-pBabe-neo (-5'UTR) was used for efficient gene transfer into primary skin fibroblasts of DA rats. After heat activation, conditioned medium from the transduced fibroblasts was found to inhibit significantly in vitro proliferation of lymphocytes from lymph nodes of DA rats with EAE. Intraperitoneal administration of TGF-beta1-transduced fibroblasts into DA rats during the priming phase of EAE resulted in a significant reduction in mortality and in the mean clinical and EAE scores versus the control immunized animals treated with non-transduced fibroblasts.

  8. Prevention of experimental autoimmune encephalomyelitis in DA rats by grafting primary skin fibroblasts engineered to express transforming growth factor-β1

    Science.gov (United States)

    Zargarova, T; Kulakova, O; Prassolov, V; Zharmukhamedova, T; Tsyganova, V; Turobov, V; Ivanov, D; Parfenov, M; Sudomoina, M; Chernajovsky, Y; Favorova, O

    2004-01-01

    To determine whether primary fibroblasts producing latent transforming growth factor β1 (TGF-β1) are capable of down-regulating experimental autoimmune encephalomyelitis (EAE), a retroviral vector TGF-β1-pBabe-neo (−5′UTR) was used for efficient gene transfer into primary skin fibroblasts of DA rats. After heat activation, conditioned medium from the transduced fibroblasts was found to inhibit significantly in vitro proliferation of lymphocytes from lymph nodes of DA rats with EAE. Intraperitoneal administration of TGF-β1-transduced fibroblasts into DA rats during the priming phase of EAE resulted in a significant reduction in mortality and in the mean clinical and EAE scores versus the control immunized animals treated with non-transduced fibroblasts. PMID:15270848

  9. Use of Natural Neural Scaffolds Consisting of Engineered Vascular Endothelial Growth Factor Immobilized on Ordered Collagen Fibers Filled in a Collagen Tube for Peripheral Nerve Regeneration in Rats

    Directory of Open Access Journals (Sweden)

    Fukai Ma

    2014-10-01

    Full Text Available The search for effective strategies for peripheral nerve regeneration has attracted much attention in recent years. In this study, ordered collagen fibers were used as intraluminal fibers after nerve injury in rats. Vascular endothelial growth factor (VEGF plays an important role in nerve regeneration, but its very fast initial burst of activity within a short time has largely limited its clinical use. For the stable binding of VEGF to ordered collagen fibers, we fused a collagen-binding domain (CBD to VEGF through recombinant DNA technology. Then, we filled the ordered collagen fibers-CBD-VEGF targeting delivery system in a collagen tube to construct natural neural scaffolds, which were then used to bridge transected nerve stumps in a rat sciatic nerve transection model. After transplantation, the natural neural scaffolds showed minimal foreign body reactions and good integration into the host tissue. Oriented collagen fibers in the collagen tube could guide regenerating axons in an oriented manner to the distal, degenerating nerve segment, maximizing the chance of target reinnervation. Functional and histological analyses indicated that the recovery of nerve function in the natural neural scaffolds-treated group was superior to the other grafted groups. The guiding of oriented axonal regeneration and effective delivery systems surmounting the otherwise rapid and short-lived diffusion of growth factors in body fluids are two important strategies in promoting peripheral nerve regeneration. The natural neural scaffolds described take advantage of these two aspects and may produce synergistic effects. These properties qualified the artificial nerve conduits as a putative candidate system for the fabrication of peripheral nerve reconstruction devices.

  10. Use of natural neural scaffolds consisting of engineered vascular endothelial growth factor immobilized on ordered collagen fibers filled in a collagen tube for peripheral nerve regeneration in rats.

    Science.gov (United States)

    Ma, Fukai; Xiao, Zhifeng; Meng, Danqing; Hou, Xianglin; Zhu, Jianhong; Dai, Jianwu; Xu, Ruxiang

    2014-10-15

    The search for effective strategies for peripheral nerve regeneration has attracted much attention in recent years. In this study, ordered collagen fibers were used as intraluminal fibers after nerve injury in rats. Vascular endothelial growth factor (VEGF) plays an important role in nerve regeneration, but its very fast initial burst of activity within a short time has largely limited its clinical use. For the stable binding of VEGF to ordered collagen fibers, we fused a collagen-binding domain (CBD) to VEGF through recombinant DNA technology. Then, we filled the ordered collagen fibers-CBD-VEGF targeting delivery system in a collagen tube to construct natural neural scaffolds, which were then used to bridge transected nerve stumps in a rat sciatic nerve transection model. After transplantation, the natural neural scaffolds showed minimal foreign body reactions and good integration into the host tissue. Oriented collagen fibers in the collagen tube could guide regenerating axons in an oriented manner to the distal, degenerating nerve segment, maximizing the chance of target reinnervation. Functional and histological analyses indicated that the recovery of nerve function in the natural neural scaffolds-treated group was superior to the other grafted groups. The guiding of oriented axonal regeneration and effective delivery systems surmounting the otherwise rapid and short-lived diffusion of growth factors in body fluids are two important strategies in promoting peripheral nerve regeneration. The natural neural scaffolds described take advantage of these two aspects and may produce synergistic effects. These properties qualified the artificial nerve conduits as a putative candidate system for the fabrication of peripheral nerve reconstruction devices.

  11. Tissue engineered periodontal products.

    Science.gov (United States)

    Bartold, P M; Gronthos, S; Ivanovski, S; Fisher, A; Hutmacher, D W

    2016-02-01

    Attainment of periodontal regeneration is a significant clinical goal in the management of advanced periodontal defects arising from periodontitis. Over the past 30 years numerous techniques and materials have been introduced and evaluated clinically and have included guided tissue regeneration, bone grafting materials, growth and other biological factors and gene therapy. With the exception of gene therapy, all have undergone evaluation in humans. All of the products have shown efficacy in promoting periodontal regeneration in animal models but the results in humans remain variable and equivocal concerning attaining complete biological regeneration of damaged periodontal structures. In the early 2000s, the concept of tissue engineering was proposed as a new paradigm for periodontal regeneration based on molecular and cell biology. At this time, tissue engineering was a new and emerging field. Now, 14 years later we revisit the concept of tissue engineering for the periodontium and assess how far we have come, where we are currently situated and what needs to be done in the future to make this concept a reality. In this review, we cover some of the precursor products, which led to our current position in periodontal tissue engineering. The basic concepts of tissue engineering with special emphasis on periodontal tissue engineering products is discussed including the use of mesenchymal stem cells in bioscaffolds and the emerging field of cell sheet technology. Finally, we look into the future to consider what CAD/CAM technology and nanotechnology will have to offer.

  12. Turning Engineering Green

    DEFF Research Database (Denmark)

    Jamison, Andrew

    2012-01-01

    Since the 1970s, the relations between engineering and development have changed significantly. On the one hand, at a discursive or macro level, there has been a shift in regard to the kind of development to which engineering is meant to contribute, from furthering economic growth to an approach t...... of these changing relations between engineering and development and distinguishes between three ideal-typical educational responses: a technical, market-oriented approach; a scientific, academic-oriented approach; and a hybrid, socially oriented approach....... to development that is “sustainable” in one way or another. On the other hand, on a practitioner, or micro level, there has been a change in the kinds of competence that engineers are expected to have in order to be able to contribute to development, due to the emergence of new fields of “technoscience” blurring...... the boundaries between what was previously considered science and what was previously considered technology. Finally, in between, at an institutional or meso level, there have been significant changes in how engineering work and engineering education are organized. This chapter attempts to provide an overview...

  13. Study of Miller timing on exhaust emissions of a hydrotreated vegetable oil (HVO)-fueled diesel engine.

    Science.gov (United States)

    Heikkilä, Juha; Happonen, Matti; Murtonen, Timo; Lehto, Kalle; Sarjovaara, Teemu; Larmi, Martti; Keskinen, Jorma; Virtanen, Annele

    2012-11-01

    The effect of intake valve closure (IVC) timing by utilizing Miller cycle and start of injection (SOI) on particulate matter (PM), particle number and nitrogen oxide (NOx) emissions was studied with a hydrotreated vegetable oil (HVO)-fueled nonroad diesel engine. HVO-fueled engine emissions, including aldehyde and polyaromatic hydrocarbon (PAH) emissions, were also compared with those emitted with fossil EN590 diesel fuel. At the engine standard settings, particle number and NOx emissions decreased at all the studied load points (50%, 75%, and 100%) when the fuel was changed from EN590 to HVO. Adjusting IVC timing enabled a substantial decrease in NOx emission and combined with SOI timing adjustment somewhat smaller decrease in both NOx and particle emissions at IVC -50 and -70 degrees CA points. The HVO fuel decreased PAH emissions mainly due to the absence of aromatics. Aldehyde emissions were lower with the HVO fuel with medium (50%) load. At higher loads (75% and 100%), aldehyde emissions were slightly higher with the HVO fuel. However, the aldehyde emission levels were quite low, so no clear conclusions on the effect of fuel can be made. Overall, the study indicates that paraffinic HVO fuels are suitable for emission reduction with valve and injection timing adjustment and thus provide possibilities for engine manufacturers to meet the strictening emission limits.

  14. Recommendation systems in software engineering

    CERN Document Server

    Robillard, Martin P; Walker, Robert J; Zimmermann, Thomas

    2014-01-01

    With the growth of public and private data stores and the emergence of off-the-shelf data-mining technology, recommendation systems have emerged that specifically address the unique challenges of navigating and interpreting software engineering data.This book collects, structures and formalizes knowledge on recommendation systems in software engineering. It adopts a pragmatic approach with an explicit focus on system design, implementation, and evaluation. The book is divided into three parts: "Part I - Techniques" introduces basics for building recommenders in software engineering, including techniques for collecting and processing software engineering data, but also for presenting recommendations to users as part of their workflow.?"Part II - Evaluation" summarizes methods and experimental designs for evaluating recommendations in software engineering.?"Part III - Applications" describes needs, issues and solution concepts involved in entire recommendation systems for specific software engineering tasks, fo...

  15. Invisible Engineers

    Science.gov (United States)

    Ohashi, Hideo

    Questionnaire to ask “mention three names of scientists you know” and “three names of engineers you know” was conducted and the answers from 140 adults were analyzed. The results indicated that the image of scientists is represented by Nobel laureates and that of engineers by great inventors like Thomas Edison and industry founders like Soichiro Honda. In order to reveal the image of engineers among young generation, questionnaire was conducted for pupils in middle and high schools. Answers from 1,230 pupils were analyzed and 226 names mentioned as engineers were classified. White votes reached 60%. Engineers who are neither big inventors nor company founders collected less than 1% of named votes. Engineers are astonishingly invisible from young generation. Countermeasures are proposed.

  16. Engineering mechanics

    CERN Document Server

    Gross, Dietmar; Schröder, Jörg; Wall, Wolfgang A; Rajapakse, Nimal

    Statics is the first volume of a three-volume textbook on Engineering Mechanics. The authors, using a time-honoured straightforward and flexible approach, present the basic concepts and principles of mechanics in the clearest and simplest form possible to advanced undergraduate engineering students of various disciplines and different educational backgrounds. An important objective of this book is to develop problem solving skills in a systematic manner. Another aim of this volume is to provide engineering students as well as practising engineers with a solid foundation to help them bridge the gap between undergraduate studies on the one hand and advanced courses on mechanics and/or practical engineering problems on the other. The book contains numerous examples, along with their complete solutions. Emphasis is placed upon student participation in problem solving. The contents of the book correspond to the topics normally covered in courses on basic engineering mechanics at universities and colleges. Now in i...

  17. Software engineering

    CERN Document Server

    Sommerville, Ian

    2010-01-01

    The ninth edition of Software Engineering presents a broad perspective of software engineering, focusing on the processes and techniques fundamental to the creation of reliable, software systems. Increased coverage of agile methods and software reuse, along with coverage of 'traditional' plan-driven software engineering, gives readers the most up-to-date view of the field currently available. Practical case studies, a full set of easy-to-access supplements, and extensive web resources make teaching the course easier than ever.

  18. Information engineering

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, D.N.

    1997-02-01

    The Information Engineering thrust area develops information technology to support the programmatic needs of Lawrence Livermore National Laboratory`s Engineering Directorate. Progress in five programmatic areas are described in separate reports contained herein. These are entitled Three-dimensional Object Creation, Manipulation, and Transport, Zephyr:A Secure Internet-Based Process to Streamline Engineering Procurements, Subcarrier Multiplexing: Optical Network Demonstrations, Parallel Optical Interconnect Technology Demonstration, and Intelligent Automation Architecture.

  19. Activist engineering: changing engineering practice by deploying praxis.

    Science.gov (United States)

    Karwat, Darshan M A; Eagle, Walter E; Wooldridge, Margaret S; Princen, Thomas E

    2015-02-01

    In this paper, we reflect on current notions of engineering practice by examining some of the motives for engineered solutions to the problem of climate change. We draw on fields such as science and technology studies, the philosophy of technology, and environmental ethics to highlight how dominant notions of apoliticism and ahistoricity are ingrained in contemporary engineering practice. We argue that a solely technological response to climate change does not question the social, political, and cultural tenet of infinite material growth, one of the root causes of climate change. In response to the contemporary engineering practice, we define an activist engineer as someone who not only can provide specific engineered solutions, but who also steps back from their work and tackles the question, What is the real problem and does this problem "require" an engineering intervention? Solving complex problems like climate change requires radical cultural change, and a significant obstacle is educating engineers about how to conceive of and create "authentic alternatives," that is, solutions that differ from the paradigm of "technologically improving" our way out of problems. As a means to realize radically new solutions, we investigate how engineers might (re)deploy the concept of praxis, which raises awareness in engineers of the inherent politics of technological design. Praxis empowers engineers with a more comprehensive understanding of problems, and thus transforms technologies, when appropriate, into more socially just and ecologically sensitive interventions. Most importantly, praxis also raises a radical alternative rarely considered-not "engineering a solution." Activist engineering offers a contrasting method to contemporary engineering practice and leads toward social justice and ecological protection through problem solving by asking not, How will we technologize our way out of the problems we face? but instead, What really needs to be done?

  20. Engineering tribology

    CERN Document Server

    Stachowiak, Gwidon; Batchelor, A W; Batchelor, Andrew W

    2005-01-01

    As with the previous edition, the third edition of Engineering Tribology provides a thorough understanding of friction and wear using technologies such as lubrication and special materials. Tribology is a complex topic with its own terminology and specialized concepts, yet is vitally important throughout all engineering disciplines, including mechanical design, aerodynamics, fluid dynamics and biomedical engineering. This edition includes updated material on the hydrodynamic aspects of tribology as well as new advances in the field of biotribology, with a focus throughout on the engineering ap

  1. Genetic engineering of cyanobacteria

    DEFF Research Database (Denmark)

    Jacobsen, Jacob Hedemand

    , including genetic tools that allow metabolic engineering. The cyanobacterial phylum represents a diverse group of aerobic photosynthetic bacteria that are widespread in nature. Cyanobacteria shaped our atmosphere by oxygen evolution through the splitting of water using energy from sunlight. The sole carbon...... and characterized for growth phenotype and glycogen content. While no difference in growth rate or glycogen content was detected between the phosphorylase double mutant and wild type strain, we found that both glycogen phophyrylases must be genetically inactivated to eliminate glycogen phosphorylase activity...

  2. Genetic engineering of cyanobacteria

    DEFF Research Database (Denmark)

    Jacobsen, Jacob Hedemand

    , including genetic tools that allow metabolic engineering. The cyanobacterial phylum represents a diverse group of aerobic photosynthetic bacteria that are widespread in nature. Cyanobacteria shaped our atmosphere by oxygen evolution through the splitting of water using energy from sunlight. The sole carbon...... and its natural ability to take up and stably integrate heterologous DNA make Synechococcus sp. PCC 7002 a good candidate for metabolic engineering. For targeted gene inactivation, a suite of vectors were made by adaptation of a system previously used in plants and fungi. The vectors include a cassette...... and characterized for growth phenotype and glycogen content. While no difference in growth rate or glycogen content was detected between the phosphorylase double mutant and wild type strain, we found that both glycogen phophyrylases must be genetically inactivated to eliminate glycogen phosphorylase activity...

  3. Fibroblast growth factor receptors in in vitro and in vivo chondrogenesis: relating tissue engineering using adult mesenchymal stem cells to embryonic development.

    Science.gov (United States)

    Hellingman, Catharine A; Koevoet, Wendy; Kops, Nicole; Farrell, Eric; Jahr, Holger; Liu, Wei; Baatenburg de Jong, Robert J; Frenz, Dorothy A; van Osch, Gerjo J V M

    2010-02-01

    Adult mesenchymal stem cells (MSCs) are considered promising candidate cells for therapeutic cartilage and bone regeneration. Because tissue regeneration and embryonic development may involve similar pathways, understanding common pathways may lead to advances in regenerative medicine. In embryonic limb development, fibroblast growth factor receptors (FGFRs) play a role in chondrogenic differentiation. The aim of this study was to investigate and compare FGFR expression in in vivo embryonic limb development and in vitro chondrogenesis of MSCs. Our study showed that in in vitro chondrogenesis of MSCs three sequential stages can be found, as in embryonic limb development. A mesenchymal condensation (indicated by N-cadherin) is followed by chondrogenic differentiation (indicated by collagen II), and hypertrophy (indicated by collagen X). FGFR1-3 are expressed in a stage-dependent pattern during in vitro differentiation and in vivo embryonic limb development. In both models FGFR2 is clearly expressed by cells in the condensation phase. No FGFR expression was observed in differentiating and mature hyaline chondrocytes, whereas hypertrophic chondrocytes stained strongly for all FGFRs. To evaluate whether stage-specific modulation of chondrogenic differentiation in MSCs is possible with different subtypes of FGF, FGF2 and FGF9 were added to the chondrogenic medium during different stages in the culture process (early or late). FGF2 and FGF9 differentially affected the amount of cartilage formed by MSCs depending on the stage in which they were added. These results will help us understand the role of FGF signaling in chondrogenesis and find new tools to monitor and control chondrogenic differentiation.

  4. Influence of epidermal growth factor (EGF) and hydrocortisone on the co-culture of mature adipocytes and endothelial cells for vascularized adipose tissue engineering.

    Science.gov (United States)

    Huber, Birgit; Czaja, Alina Maria; Kluger, Petra Juliane

    2016-05-01

    The composition of vascularized adipose tissue is still an ongoing challenge as no culture medium is available to supply adipocytes and endothelial cells appropriately. Endothelial cell medium is typically supplemented with epidermal growth factor (EGF) as well as hydrocortisone (HC). The effect of EGF on adipocytes is discussed controversially. Some studies say it inhibits adipocyte differentiation while others reported of improved adipocyte lipogenesis. HC is known to have lipolytic activities, which might result in mature adipocyte dedifferentiation. In this study, we evaluated the influence of EGF and HC on the co-culture of endothelial cells and mature adipocytes regarding their cell morphology and functionality. We showed in mono-culture that high levels of HC promoted dedifferentiation and proliferation of mature adipocytes, whereas EGF seemed to have no negative influence. Endothelial cells kept their typical cobblestone morphology and showed a proliferation rate comparable to the control independent of EGF and HC concentration. In co-culture, HC promoted dedifferentiation of mature adipocytes, which was shown by a higher glycerol release. EGF had no negative impact on adipocyte morphology. No negative impact on endothelial cell morphology and functionality could be seen with reduced EGF and HC supplementation in co-culture with mature adipocytes. Taken together, our results demonstrate that reduced levels of HC are needed for co-culturing mature adipocytes and endothelial cells. In co-culture, EGF had no influence on mature adipocytes. Therefore, for the composition of vascularized adipose tissue constructs, the media with low levels of HC and high or low levels of EGF can be used.

  5. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>20142564Chen Mingxing(Beijing Research Institute of Survey and Design,China Hydropower Engineering Consulting Group Co.,Beijing 100024,China);Chen Baoguo Application of Drilling Deviation Correcting and Deflecting Techniques in Geological Exploration at Songta Hydropower Station(Exploration Engineering,ISSN1672-7428,CN11-5063/TD,

  6. Systems Engineering

    Science.gov (United States)

    Pellerano, Fernando

    2015-01-01

    This short course provides information on what systems engineering is and how the systems engineer guides requirements, interfaces with the discipline leads, and resolves technical issues. There are many system-wide issues that either impact or are impacted by the thermal subsystem. This course will introduce these issues and illustrate them with real life examples.

  7. Governing Engineering

    DEFF Research Database (Denmark)

    Buch, Anders

    2012-01-01

    of knowledge, belief and opinions in which engineering is immersed. Thus the overall objective is explorative. By investigating the language, practices and techniques by which engineering is governed the chapter sets out to point to the presumptions, stipulations and ‘limits’ of the dominant discourses...

  8. Biomedical Engineering

    CERN Document Server

    Suh, Sang C; Tanik, Murat M

    2011-01-01

    Biomedical Engineering: Health Care Systems, Technology and Techniques is an edited volume with contributions from world experts. It provides readers with unique contributions related to current research and future healthcare systems. Practitioners and researchers focused on computer science, bioinformatics, engineering and medicine will find this book a valuable reference.

  9. Corrosion Engineering.

    Science.gov (United States)

    White, Charles V.

    A description is provided for a Corrosion and Corrosion Control course offered in the Continuing Engineering Education Program at the General Motors Institute (GMI). GMI is a small cooperative engineering school of approximately 2,000 students who alternate between six-week periods of academic study and six weeks of related work experience in…

  10. Food Engineering

    NARCIS (Netherlands)

    Boom, R.M.; Janssen, A.E.M.

    2014-01-01

    Food engineering is a rapidly changing discipline. Traditionally, the main focus was on food preservation and stabilization, whereas trends now are on diversity, health, taste, and sustainable production. Next to a general introduction of the definition of food engineering, this article gives a

  11. Genetic Engineering

    Science.gov (United States)

    Phillips, John

    1973-01-01

    Presents a review of genetic engineering, in which the genotypes of plants and animals (including human genotypes) may be manipulated for the benefit of the human species. Discusses associated problems and solutions and provides an extensive bibliography of literature relating to genetic engineering. (JR)

  12. Emotional engineering

    CERN Document Server

    In an age of increasing complexity, diversification and change, customers expect services that cater to their needs and to their tastes. Emotional Engineering vol 2. describes how their expectations can be satisfied and managed throughout the product life cycle, if producers focus their attention more on emotion. Emotional engineering provides the means to integrate products to create a new social framework and develops services beyond product realization to create of value across a full lifetime.  14 chapters cover a wide range of topics that can be applied to product, process and industry development, with special attention paid to the increasing importance of sensing in the age of extensive and frequent changes, including: • Multisensory stimulation and user experience  • Physiological measurement • Tactile sensation • Emotional quality management • Mental model • Kansei engineering.   Emotional Engineering vol 2 builds on Dr Fukuda’s previous book, Emotional Engineering, and provides read...

  13. Engineering surveying

    CERN Document Server

    Schofield, W

    2001-01-01

    The aim of Engineering Surveying has always been to impart and develop a clear understanding of the basic topics of the subject. The author has fully revised the book to make it the most up-to-date and relevant textbook available on the subject.The book also contains the latest information on trigonometric levelling, total stations and one-person measuring systems. A new chapter on satellites ensures a firm grasp of this vitally important topic.The text covers engineering surveying modules for civil engineering students on degree courses and forms a reference for the engineering surveying module in land surveying courses. It will also prove to be a valuable reference for practitioners.* Simple clear introduction to surveying for engineers* Explains key techniques and methods* Details reading systems and satellite position fixing

  14. Architectural Engineers

    DEFF Research Database (Denmark)

    Petersen, Rikke Premer

    The design professions have always been an amorphous phenomena difficult to merge under one label. New constellations continually emerge, questioning, stretching, and reconfiguring the understanding of design and the professional practices linked to it. In this paper the idea of architectural...... engineering is addresses from two perspectives – as an educational response and an occupational constellation. Architecture and engineering are two of the traditional design professions and they frequently meet in the occupational setting, but at educational institutions they remain largely estranged....... The paper builds on a multi-sited study of an architectural engineering program at the Technical University of Denmark and an architectural engineering team within an international engineering consultancy based on Denmark. They are both responding to new tendencies within the building industry where...

  15. MPLS & Internet Traffic Engineering%MPLS和Internet流量工程

    Institute of Scientific and Technical Information of China (English)

    孟魁; 张根度

    2001-01-01

    Rapid growth of Internet traffic and increasing requirement for service quality have made traffic engineering an essential consideration in the operation of large Internet backbone networks. Historically,traffic engineering in the Internet has been hampered by the conventional IP technologies. This article discusses the challenge of Internet Traffic Engineering and the applications of MPLS to traffic engineering in IP networks.

  16. Myanmar Language Search Engine

    Directory of Open Access Journals (Sweden)

    Pann Yu Mon

    2011-03-01

    Full Text Available With the enormous growth of the World Wide Web, search engines play a critical role in retrieving information from the borderless Web. Although many search engines are available for the major languages, but they are not much proficient for the less computerized languages including Myanmar. The main reason is that those search engines are not considering the specific features of those languages. A search engine which capable of searching the Web documents written in those languages is highly needed, especially when more and more Web sites are coming up with localized content in multiple languages. In this study, the design and the architecture of language specific search engine for Myanmar language is proposed. The main feature of the system are, (1 it can search the multiple encodings of the Myanmar Web page, (2 the system is designed to comply with the specific features of the Myanmar language. Finally the experiment has been done to prove whether it meets the design requirements.

  17. RAM Engineering

    Science.gov (United States)

    2011-06-02

    Program Plan - CDRL)  R Prediction  R Allocation  FMEA  Fault Tree Analysis  DART Process  The growth resulting from DFR activities tracked on the...R Allocation FMEA Fault Tree Analysis Unclassified/FOUO Reliability Growth during Test Phase  Reliability Growth management during Test phase (PQT

  18. Genotoxic potential of organic extracts from particle emissions of diesel and rapeseed oil powered engines.

    Science.gov (United States)

    Topinka, Jan; Milcova, Alena; Schmuczerova, Jana; Mazac, Martin; Pechout, Martin; Vojtisek-Lom, Michal

    2012-07-07

    The present study was performed to identify possible genotoxicity induced by organic extracts from particulate matter in the exhaust of two typical diesel engines run on diesel fuel and neat heated fuel-grade rapeseed oil: a Cummins ISBe4 engine tested using the World Harmonized Steady State Test Cycle (WHSC) and modified Engine Steady Cycle (ESC) and a Zetor 1505 engine tested using the Non-Road Steady State Cycle (NRSC). In addition, biodiesel B-100 (neat methylester of rapeseed oil) was tested in the Cummins engine run on the modified ESC. Diluted exhaust was sampled with high-volume samplers on Teflon coated filters. Filters were extracted with dichlormethane (DCM) and DNA adduct levels induced by extractable organic matter (EOM) in an acellular assay of calf thymus DNA coupled with (32)P-postlabeling in the presence and absence of rat liver microsomal S9 fraction were employed. Simultaneously, the chemical analysis of 12 priority PAHs in EOM, including 7 carcinogenic PAHs (c-PAHs) was performed. The results suggest that diesel emissions contain substantially more total PAHs than rapeseed oil emissions (for the ESC) or that these concentrations were comparable (for the WHSC and NRSC), while c-PAHs levels were comparable (for the ESC) or significantly higher (for the WHSC and NRSC) for rapeseed oil emissions. DNA adduct levels induced by diesel and rapeseed oil derived EOM were comparable, but consistently slightly higher for diesel than for rapeseed oil. Highly significant correlations were found between 12 priority PAHs concentrations and DNA adduct levels (0.980; pparticulate emissions from the combustion of rapeseed oil is significant and is comparable to that from the combustion of diesel fuel. A more detailed study is ongoing to verify and extent these preliminary findings. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  19. Engineering mathematics

    CERN Document Server

    Stroud, K A

    2013-01-01

    A groundbreaking and comprehensive reference that's been a bestseller since it first debuted in 1970, the new seventh edition of Engineering Mathematics has been thoroughly revised and expanded. Providing a broad mathematical survey, this innovative volume covers a full range of topics from the very basic to the advanced. Whether you're an engineer looking for a useful on-the-job reference or want to improve your mathematical skills, or you are a student who needs an in-depth self-study guide, Engineering Mathematics is sure to come in handy time and time again.

  20. Reduction of NOx Emission of a Diesel Engine with a Multiple Injection Pump by SCR Catalytic Converter

    Directory of Open Access Journals (Sweden)

    Vít Marek

    2016-01-01

    Full Text Available This paper deals with reduction of NOx-emission of a diesel engine with multiple injection pump by SCR catalytic converter. Main aim of the measurement was the detection of SCR catalyst converter efficiency. Tests were realized at the Research and Development workplace of Zetor Tractor a.s. Used engine was equipped with a multiple injection pump with electromagnetic regulator of a fuel charge. During the experiment selective catalytic reduction and diesel particulate filter were used as an after treatment of harmful pollutants reduction. Testing cycle of the eight-point test was chosen and Non-Road Steady Cycle (NRSC was maintained according to 97/68/EC directive. Results confirmed the dependencies between temperatures of SCR catalyst and exhaust gases and the volume of exhaust gases on efficiency of SCR catalyst. During the operation load of the engine, selective catalytic reduction reached efficiency over 90 %. Used after treatment system is suitable for reduction of harmful pollutants according to the Tier 4f norm.

  1. Sustainability issues in civil engineering

    CERN Document Server

    Saride, Sireesh; Basha, B

    2017-01-01

    This compilation on sustainability issues in civil engineering comprises contributions from international experts who have been working in the area of sustainability in civil engineering. Many of the contributions have been presented as keynote lectures at the International Conference on Sustainable Civil Infrastructure (ICSCI) held in Hyderabad, India. The book has been divided into core themes of Sustainable Transportation Systems, Sustainable Geosystems, Sustainable Environmental and Water Resources and Sustainable Structural Systems. Use of sustainability principles in engineering has become an important component of the process of design and in this context, design and analysis approaches in civil engineering are being reexamined to incorporate the principles of sustainable designs and construction in practice. Developing economies are on the threshold of rapid infrastructure growth and there is a need to compile the developments in various branches of civil engineering and highlight the issues. It is th...

  2. Coastal Engineering

    NARCIS (Netherlands)

    Van der Velden, E.T.J.M.

    1989-01-01

    Introduction, waves, sediment transport, littoral transport, lonshore sediment transport, onshore-offshore sediment transport, coastal changes, dune erosion and storm surges, sedimentation in channels and trenches, coastal engineering in practice.

  3. Green Engineering

    Science.gov (United States)

    Green Engineering is the design, commercialization and use of processes and products that are feasible and economical while reducing the generation of pollution at the source and minimizing the risk to human health and the environment.

  4. Harmonic engine

    Science.gov (United States)

    Bennett, Charles L.

    2009-10-20

    A high efficiency harmonic engine based on a resonantly reciprocating piston expander that extracts work from heat and pressurizes working fluid in a reciprocating piston compressor. The engine preferably includes harmonic oscillator valves capable of oscillating at a resonant frequency for controlling the flow of working fluid into and out of the expander, and also preferably includes a shunt line connecting an expansion chamber of the expander to a buffer chamber of the expander for minimizing pressure variations in the fluidic circuit of the engine. The engine is especially designed to operate with very high temperature input to the expander and very low temperature input to the compressor, to produce very high thermal conversion efficiency.

  5. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20112760 Dai Guozhong (College of Civil Engineering,Changzhou Institute of Tech- nology,Changzhou 213002,China);Zhang Yaxing Study on Solid-Free Drilling Fluid of PVM Polymer and Its Application (Geology

  6. Engineering Geology.

    Science.gov (United States)

    Ivey, John B.

    1983-01-01

    Engineering geology activities in government and the private sector are highlighted. Also highlighted are conferences in this field, awards presented at conferences (including an award to an undergraduate geology student), and a new publication "Geotechnology in Massachusetts." (JN)

  7. Rehabilitation Engineering: What is Rehabilitation Engineering?

    Science.gov (United States)

    ... Parents/Teachers Resource Links for Students Glossary Rehabilitation Engineering What is rehabilitation engineering? How can future rehabilitation ... the area of rehabilitation engineering? What is rehabilitation engineering? Powered prosthetic leg. Source : M. Goldfarb, Vanderbilt U. ...

  8. Microwave engineering

    CERN Document Server

    Pozar, David M

    2012-01-01

    The 4th edition of this classic text provides a thorough coverage of RF and microwave engineering concepts, starting from fundamental principles of electrical engineering, with applications to microwave circuits and devices of practical importance.  Coverage includes microwave network analysis, impedance matching, directional couplers and hybrids, microwave filters, ferrite devices, noise, nonlinear effects, and the design of microwave oscillators, amplifiers, and mixers. Material on microwave and RF systems includes wireless communications, radar, radiometry, and radiation hazards. A large

  9. 影响西部地区工科院校青年教师成长的因素分析%Influencing Factors of Growth of Young Teachers in Western Engineering Colleges

    Institute of Scientific and Technical Information of China (English)

    曾华辉; 杨雅琼; 陶春莉

    2011-01-01

    西部地区工科院校青年教师成长速度过慢已成为制约其发展的主要原因,本文从西部地区工科院校青年教师培养过程中出现的问题着手,分析了影响工科院校青年教师成长的四大因素:1缺乏系统的教育专业知识作指导;2人文精神淡薄;3工程素质差、缺乏实践教学能力素养;④进修机会少,知识更新慢.并据此提出了四点对策:1转变教育观念;2加强人文素质修养;3大力开展教师培训,丰富培训内容;④完善师资管理运行体制.以期为加快工科院校青年教师成长提供一些参考.%The growing speed of young teachers in western engineering colleges is the main factor of restricting its development.The thesis starts from the problems in cultivation of young teachers, analyzes the four influencing factors: ①lack of systematical educational professional knowledge;②be weak in humanistic spirit; ③engineering quality is poor; lack of practical teaching ability; ④the chance of advanced study is little; the refresh rate of knowledge is low.At last, four measures are put forward, in order to provide reference for speeding up the growth of young teachers:①convert educational concept; ②strengthen cultivate quality of humanities; ③carry out train of teachers vigorously; enrich training content; ④improve operation system of teacher resources management.

  10. 重组人胰岛素样生长因子1工程菌的高密度发酵%High cell-density fermentation of recombinant human insulin-like growth factor-1 engineering bacteria

    Institute of Scientific and Technical Information of China (English)

    陈蔚青; 张建芬; 陈虹; 胡文浪

    2009-01-01

    BACKGROUND:Insulin-like growth factor-1(IGF-1)is an important cell factor which plays a special role in many disease treatments such as diabetes.The research of engineering bacteria fermentation production technology is great to IGF-1 industrialization and to clinical application.OBJECTIVE:To investigate the high cell-density fermentation and expression condition of recombinant human insulin-like growth factor-1(IGF-1) engineering bacteria.DESIGN,TIME AND SETTING:The enzyme,gene engineering,study was performed at the Biotechnological Laboratory of Zhejiang Shuren University from May 2007 to May 2008.MATERIALS:Recombinant E coli strain for IGF-1 expression as BL21 (DE3)/pET22a-IGF-1 was reserved in the Biotechnological Laboratory of Zhejiang Shuren University.Nutrient feed was composed of:glucose(300 g/L),peptone(40 g/L),yeast powder(10 g/L),Na2HPO4(280 mmol/L),Na2HPO4-2H2O2(120 mmol/L),MgSO4(10 mmol/L),and ampicillin(100 mg/L).METHODS:The strains were activated and then cultured in orbitaI shakers.Parameters such as types of media,isopropyl-β-D-thiogalactopyranoside(IPTG)concentration and induction time have been analyzed to explore optimaI fermentation conditions for expressing the recombinant protein.According to the optimal fermentation condition of orbitaI shakers.batch fermentation was carried on with 5 L-autocontroI fermentor.The process contained two stages:batch culture and fed-bafch through pH-stat solution.JPTG was added to jnduce the expression of protein in the middle and latter of the logarithmic growth phase for 4-βhours.MAIN OUTCOME MEASURES:Following described parameters were measured:fermentation and protein expression of the recombinant human IGF-1 engineering bacteria,cell concentration,cell dry weigh,objective protein,glucose concentration.RESULTS:Cells were cultured in 2×YT+5 g,L glucose medium,induced by 0.8 mmol/L IPTG for 5 hours.By controlling dissolved oxygen and by pH-stat feeding solution,high cell-density and high protein expression

  11. Engineering Optics

    CERN Document Server

    Iizuka, Keigo

    2008-01-01

    Engineering Optics is a book for students who want to apply their knowledge of optics to engineering problems, as well as for engineering students who want to acquire the basic principles of optics. It covers such important topics as optical signal processing, holography, tomography, holographic radars, fiber optical communication, electro- and acousto-optic devices, and integrated optics (including optical bistability). As a basis for understanding these topics, the first few chapters give easy-to-follow explanations of diffraction theory, Fourier transforms, and geometrical optics. Practical examples, such as the video disk, the Fresnel zone plate, and many more, appear throughout the text, together with numerous solved exercises. There is an entirely new section in this updated edition on 3-D imaging.

  12. Engineering physics

    CERN Document Server

    Mukherji, Uma

    2015-01-01

    ENGINEERING PHYSICS is designed as a textbook for first year engineering students of a two semester course in Applied Physics according to new revised syllabus. However the scope of this book is not only limited to undergraduate engineering students and science students, it can also serve as a reference book for practicing scientists.Advanced technological topics like LCD, Squid, Maglev system, Electron microscopes, MRI, Photonics - Photonic fibre, Nano-particles, CNT, Quantum computing etc., are explained with basic underlying principles of Physics.This text explained following topics with numerous solved, unsolved problems and questions from different angles. Part-I contains crystal structure, Liquid crystal, Thermo-electric effect, Thermionic emission, Ultrasonic, Acoustics, semiconductor and magnetic materials. Whereas Part-2 contains Optics, X-rays, Electron optics, Dielectric materials, Quantum Physics and Schrodinger wave equation, Laser, Fibre-optics and Holography, Radio-activity, Super-conductivity,...

  13. Engineering surveying

    CERN Document Server

    Schofield, W

    2007-01-01

    Engineering surveying involves determining the position of natural and man-made features on or beneath the Earth's surface and utilizing these features in the planning, design and construction of works. It is a critical part of any engineering project. Without an accurate understanding of the size, shape and nature of the site the project risks expensive and time-consuming errors or even catastrophic failure.Engineering Surveying 6th edition covers all the basic principles and practice of this complex subject and the authors bring expertise and clarity. Previous editions of this classic text have given readers a clear understanding of fundamentals such as vertical control, distance, angles and position right through to the most modern technologies, and this fully updated edition continues that tradition.This sixth edition includes:* An introduction to geodesy to facilitate greater understanding of satellite systems* A fully updated chapter on GPS, GLONASS and GALILEO for satellite positioning in surveying* Al...

  14. ENGINEERING GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>20091943 Cao Zubao(Xi’an Branch of China Coal Research Institute,Xi’an 710054,China);Zhu Mingcheng Application of Pipe-Roof Curtain Grouting in Construction of Coal Mine Tunnel Crossing the Fractured Zone(Exploration Engineering,ISSN1672-7428,CN11-5063/TD,35(8),2008,p.79-81,3 illus.,4 refs.,with English abstract)Key words:curtain grouting20091944 Chen Changfu(Civil Engineering College,Hunan University,Changsha 410082,China);Xiao Shujun Application of Weighted Residual Method in Whole Internal Force Calculation of Anti-Slide Pile(Hydrogeology and Engineering Geology,ISSN1000-3665,CN11-2202/P,35(4),2008,p.75-79,3 illus.,9 refs.)Key words:slide-resistant

  15. Genetic engineering in biotechnology

    Energy Technology Data Exchange (ETDEWEB)

    Bedate, C.A.; Morales, J.C.; Lopez, E.H.

    1981-09-01

    The objective of this book is to encourage the use of genetic engineering for economic development. The report covers: (1) Precedents of genetic engineering; (2) a brief description of the technology, including the transfer of DNA in bacteria (vectors, E. coli and B. subtilis hosts, stages, and technical problems), practical examples of techniques used and their products (interferon; growth hormone; insulin; treatment of blood cells, Talasemia, and Lesch-Nyhan syndrome; and more nutritious soya), transfer to higher organisms, and cellular fusion; (3) biological risks and precautions; (4) possible applications (production of hydrogen, hydrocarbons, alcohol, chemicals, enzymes, peptides, viral antigens, monoclonal antibodies, genes, proteins, and insecticides; metal extraction; nitrogen fixation; biodegradation; and new varieties of plants and animals; and (5) international activities.

  16. Micro Engineering

    DEFF Research Database (Denmark)

    Alting, Leo; Kimura, F.; Hansen, Hans Nørgaard

    2003-01-01

    The paper addresses the questions of how micro products are designed and how they are manufactured. Definitions of micro products and micro engineering are discussed and the presentation is aimed at describing typical issues, possibilities and tools regarding design of micro products. The implica......The paper addresses the questions of how micro products are designed and how they are manufactured. Definitions of micro products and micro engineering are discussed and the presentation is aimed at describing typical issues, possibilities and tools regarding design of micro products...

  17. ENGINEERING GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>20140498An Shize(Sichuan Institute of Geological Engineering Investigation,Chengdu610072,China);Liu Zongxiang On the Failure Mechanism of a Bedding Landslide in Northeast Sichuan(Journal of Geological Hazards and Environment Preservation,ISSN1006-4362,CN51-1467/P,24(1),2013,p.14-19,2illus.,9refs.)Key words:bedding faults,landslides The landslide was caused by excavation engineering.The failure mechanism is explored for slopes with soft interlayer in the red

  18. Software engineering

    CERN Document Server

    Thorin, Marc

    1985-01-01

    Software Engineering describes the conceptual bases as well as the main methods and rules on computer programming. This book presents software engineering as a coherent and logically built synthesis and makes it possible to properly carry out an application of small or medium difficulty that can later be developed and adapted to more complex cases. This text is comprised of six chapters and begins by introducing the reader to the fundamental notions of entities, actions, and programming. The next two chapters elaborate on the concepts of information and consistency domains and show that a proc

  19. Engineering tribology

    CERN Document Server

    Stachowiak, Gwidon

    2013-01-01

    Engineering Tribology, 4th Edition is an established introductory reference focusing on the key concepts and engineering implications of tribology. Taking an interdisciplinary view, the book brings together the relevant knowledge from different fields needed to achieve effective analysis and control of friction and wear. Updated to cover recent advances in tribology, this new edition includes new sections on ionic and mesogenic lubricants, surface texturing, and multiscale characterization of 3D surfaces and coatings. Current trends in nanotribology are discussed, such as those relating to

  20. Lightwave engineering

    CERN Document Server

    Kokubun, Yasuo

    2012-01-01

    Suitable as either a student text or professional reference, Lightwave Engineering addresses the behavior of electromagnetic waves and the propagation of light, which forms the basis of the wide-ranging field of optoelectronics. Divided into two parts, the book first gives a comprehensive introduction to lightwave engineering using plane wave and then offers an in-depth analysis of lightwave propagation in terms of electromagnetic theory. Using the language of mathematics to explain natural phenomena, the book includes numerous illustrative figures that help readers develop an intuitive unders

  1. Engineering vascularized skeletal muscle tissue

    NARCIS (Netherlands)

    Levenberg, Shulamit; Rouwkema, Jeroen; Macdonald, Mara; Garfein, Evan S.; Kohane, Daniel S.; Darland, Diane C.; Marini, Robert; van Blitterswijk, Clemens; Mulligan, Richard C.; D'Amore, Patricia A.; Langer, Robert

    2005-01-01

    One of the major obstacles in engineering thick, complex tissues such as muscle is the need to vascularize the tissue in vitro. Vascularization in vitro could maintain cell viability during tissue growth, induce structural organization and promote vascularization upon implantation. Here we describe

  2. Growth Hormone

    Science.gov (United States)

    ... AACC products and services. Advertising & Sponsorship: Policy | Opportunities Growth Hormone Share this page: Was this page helpful? Also known as: GH; Human Growth Hormone; HGH; Somatotropin; Growth Hormone Stimulation Test; Growth ...

  3. Photoreceptor engineering

    Directory of Open Access Journals (Sweden)

    Thea eZiegler

    2015-06-01

    Full Text Available Sensory photoreceptors not only control diverse adaptive responses in Nature, but as light-regulated actuators they also provide the foundation for optogenetics, the non-invasive and spatiotemporally precise manipulation of cellular events by light. Novel photoreceptors have been engineered that establish control by light over manifold biological processes previously inaccessible to optogenetic intervention. Recently, photoreceptor engineering has witnessed a rapid development, and light-regulated actuators for the perturbation of a plethora of cellular events are now available. Here, we review fundamental principles of photoreceptors and light-regulated allostery. Photoreceptors dichotomize into associating receptors that alter their oligomeric state as part of light-regulated allostery and non-associating receptors that do not. A survey of engineered photoreceptors pinpoints light-regulated association reactions and order-disorder transitions as particularly powerful and versatile design principles. Photochromic photoreceptors that are bidirectionally toggled by two light colors augur enhanced spatiotemporal resolution and use as photoactivatable fluorophores. By identifying desirable traits in engineered photoreceptors, we provide pointers for the design of future, light-regulated actuators.

  4. Exhibit Engineering

    DEFF Research Database (Denmark)

    Mortensen, Marianne Foss

    ) a synthesis of the findings from the first two studies with findings from the literature to generate two types of results: a coherent series of suggestions for a design iteration of the studied exhibit as well as a more general normative model for exhibit engineering. Finally, another perspective...

  5. Concurrent engineering

    Science.gov (United States)

    Chamis, C. C.; Leger, L.; Hunter, D.; Jones, C.; Sprague, R.; Berke, L.; Newell, J.; Singhal, S.

    1991-01-01

    The following subject areas are covered: issues (liquid rocket propulsion - current development approach, current certification process, and costs of engineering changes); state of the art (DICE information management system, key government participants, project development strategy, quality management, and numerical propulsion system simulation); needs identified; and proposed program.

  6. Geospatial Engineering

    Science.gov (United States)

    2017-02-22

    drinking , sanitation, food preparation, construction, and decontamination. Support activities (helicopter maintenance , operation of medical facilities...analyses to find water sources for wells and key infrastructure locations. There are additional missions performed by geospatial engineers during the...polygons). Each feature can include embedded information (attributes) (body- of- water bank heights, road surface type, road width, bridge load-bearing

  7. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    <正>20051144 Gu Jun (Petroleum University, Beijing); Gao Deli Analysis of Mechanic Characterstics for Coal Bed and Drilling Countermeasure in Tuha Basin, Xinjiang, China (Exploration Engineering (Rock & Soil Drilling and Tunneling), ISSN 1672 - 7428, CN11-5063/TD, 31(5), 2004, p. 51-52, 55, 3 tables, 1 ref. , with English abstract) Key words: coal seams, drilling

  8. Micro Engineering

    DEFF Research Database (Denmark)

    Alting, Leo; Kimura, F.; Hansen, Hans Nørgaard

    2003-01-01

    The paper addresses the questions of how micro products are designed and how they are manufactured. Definitions of micro products and micro engineering are discussed and the presentation is aimed at describing typical issues, possibilities and tools regarding design of micro products. The implica...

  9. Concurrency engineering

    NARCIS (Netherlands)

    Jesshope, C.; Shafarenko, A.

    2008-01-01

    This is a discussion paper on a very important topic that is about to become mainstream. It deals with the issues of software engineering in concurrent systems. It introduces this topic and illustrates the arguments for a change of perspective. It underlines these arguments with two examples, an

  10. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2016-01-01

    20161419Cao Baomin(Shaanxi Binchang Xiaozhuang Mining Co.Ltd,Binxian 7135000,China);Zhang Jianghao Application of Rotary Drilling Combination to Pile Foundation Engineering in Xiaozhuang Mine,Shaanxi Province(Geology of Shaanxi,ISSN1001-6996,CN61

  11. Engineering Ontologies

    NARCIS (Netherlands)

    Borst, Pim; Akkermans, Hans; Top, Jan

    1997-01-01

    We analyse the construction as well as the role of ontologies in knowledge sharing and reuse for complex industrial applications. In this article, the practical use of ontologies in large-scale applications not restricted to knowledge-based systems is demonstrated, for the domain of engineering syst

  12. Enhancing Engineering Education through Engineering Management

    Science.gov (United States)

    Pence, Kenneth R.; Rowe, Christopher J.

    2012-01-01

    Engineering Management courses are added to a traditional engineering curriculum to enhance the value of an undergraduate's engineering degree. A four-year engineering degree often leaves graduates lacking in business and management acumen. Engineering management education covers topics enhancing the value of new graduates by teaching management…

  13. Business plan basics for engineers

    DEFF Research Database (Denmark)

    Tanev, Stoyan; Rasmussen, Erik Stavnsager; Riber Hansen, Katrine

    2016-01-01

    This chapter focuses on the nature of business planning activities from an engineering entre-/intra-preneurial perspective. It is therefore not limited to technology start-ups or newly created engineering firms but equally relevant for established firms investing in projects that assemble...... and deploy highly qualified human resources and heterogeneous assets that are intricately related to advances in scientific, engineering and technological knowledge for the purpose of creating and capturing value for the firm. After discussing the unique char-acteristics and challenges of technology......-driven business environments which are typical the business playground for engineering professionals, the chapter focuses on describing the two key components of the business planning process: the articulation and the development of a viable business model, and managing the scaling up and the growth...

  14. Business plan basics for engineers

    DEFF Research Database (Denmark)

    Tanev, Stoyan; Rasmussen, Erik Stavnsager; Riber Hansen, Katrine

    2016-01-01

    -driven business environments which are typical the business playground for engineering professionals, the chapter focuses on describing the two key components of the business planning process: the articulation and the development of a viable business model, and managing the scaling up and the growth......This chapter focuses on the nature of business planning activities from an engineering entre-/intra-preneurial perspective. It is therefore not limited to technology start-ups or newly created engineering firms but equally relevant for established firms investing in projects that assemble...... of the business. The de-scription does not pretend to exhaust the topic and continuously refers to several excellent recent publications that could complement the learning process of young and advanced engi-neering professionals interested in knowing more about the business planning process....

  15. Ion beam assisted film growth

    CERN Document Server

    Itoh, T

    2012-01-01

    This volume provides up to date information on the experimental, theoretical and technological aspects of film growth assisted by ion beams.Ion beam assisted film growth is one of the most effective techniques in aiding the growth of high-quality thin solid films in a controlled way. Moreover, ion beams play a dominant role in the reduction of the growth temperature of thin films of high melting point materials. In this way, ion beams make a considerable and complex contribution to film growth. The volume will be essential reading for scientists, engineers and students working in thi

  16. Engineering Review Information System

    Science.gov (United States)

    Grems, III, Edward G. (Inventor); Henze, James E. (Inventor); Bixby, Jonathan A. (Inventor); Roberts, Mark (Inventor); Mann, Thomas (Inventor)

    2015-01-01

    A disciplinal engineering review computer information system and method by defining a database of disciplinal engineering review process entities for an enterprise engineering program, opening a computer supported engineering item based upon the defined disciplinal engineering review process entities, managing a review of the opened engineering item according to the defined disciplinal engineering review process entities, and closing the opened engineering item according to the opened engineering item review.

  17. Global Software Engineering: A Software Process Approach

    Science.gov (United States)

    Richardson, Ita; Casey, Valentine; Burton, John; McCaffery, Fergal

    Our research has shown that many companies are struggling with the successful implementation of global software engineering, due to temporal, cultural and geographical distance, which causes a range of factors to come into play. For example, cultural, project managementproject management and communication difficulties continually cause problems for software engineers and project managers. While the implementation of efficient software processes can be used to improve the quality of the software product, published software process models do not cater explicitly for the recent growth in global software engineering. Our thesis is that global software engineering factors should be included in software process models to ensure their continued usefulness in global organisations. Based on extensive global software engineering research, we have developed a software process, Global Teaming, which includes specific practices and sub-practices. The purpose is to ensure that requirements for successful global software engineering are stipulated so that organisations can ensure successful implementation of global software engineering.

  18. Tissue engineering for periodontal regeneration.

    Science.gov (United States)

    Kao, Richard T; Conte, Greg; Nishimine, Dee; Dault, Scott

    2005-03-01

    As a result of periodontal regeneration research, a series of clinical techniques have emerged that permit tissue engineering to be performed for more efficient regeneration and repair of periodontal defects and improved implant site development. Historically, periodontal regeneration research has focused on a quest for "magic filler" material. This search has led to the development of techniques utilizing autologous bone and bone marrow, allografts, xenografts, and various man-made bone substitutes. Though these techniques have had limited success, the desire for a more effective regenerative approach has resulted in the development of tissue engineering techniques. Tissue engineering is a relatively new field of reconstructive biology which utilizes mechanical, cellular, or biologic mediators to facilitate reconstruction/regeneration of a particular tissue. In periodontology, the concept of tissue engineering had its beginnings with guided tissue regeneration, a mechanical approach utilizing nonresorbable membranes to obtain regeneration in defects. In dental implantology, guided bone regeneration membranes +/- mechanical support are used for bone augmentation of proposed implant placement sites. With the availability of partially purified protein mixture from developing teeth and growth factors from recombinant technology, a new era of tissue engineering whereby biologic mediators can be used for periodontal regeneration. The advantage of recombinant growth factors is this tissue engineering device is consistent in its regenerative capacity, and variations in regenerative response are due to individual healing response and/or poor surgical techniques. In this article, the authors review how tissue engineering has advanced and discuss its impact on the clinical management of both periodontal and osseous defects in preparation for implant placement. An understanding of these new tissue engineering techniques is essential for comprehending today's ever

  19. Tissue engineering for clinical applications.

    Science.gov (United States)

    Bhatia, Sujata K

    2010-12-01

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

  20. Are women engineers in Lebanon prepared for the challenges of an engineering profession?

    Science.gov (United States)

    Baytiyeh, Hoda

    2013-08-01

    This study investigates the status of women engineers in the Middle East, considering women engineers in Lebanon as a case study. The author investigated the following questions: What are the influences behind females' decisions to choose engineering as their major course of study? What are the motives behind this decision? What are the perceptions of females regarding the essential skills for a successful engineering career? An online survey consisting of Likert-scale items was completed by 327 female engineers who graduated from universities in Lebanon and now work in various locations around the world. A genuine interest in the field appeared to be the main influence in the participants' decisions to choose engineering profession. The potential for professional growth was the leading motivator for choosing engineering. Although participants reported that they possessed adequate theoretical knowledge and technical skills before graduation, in the actual practice of engineering, they noted weaknesses in creativity and innovation.

  1. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>20092040 Chen Jing(College of Petroleum Engineering,Yangtze University,Jingzhou 434023,China);Xiong Qingshan Technology of Well Cementing with Expandable Tube and Its Application(Exploration Engineering,ISSN1672-7428,CN11-5063/TD,35(8),2008,p.19-21,4 illus.,2 tables,5 refs.)Key words:cementingExpandable tube is a new technology and has been developed oversea.It can be applied in well drilling and completion for deep water,deep well,extended reach well and multilateral well,as well as in oil extraction and workover.This paper briefly introduces the technology of well cementing with

  2. Heat engines

    Science.gov (United States)

    Rekos, N. F., Jr.; Parsons, E. L., Jr.

    1989-09-01

    For the past decade, the Department of Energy (DOE) has sponsored projects to develop diesel and gas turbine engines capable of operating on low-cost, coal-based fuels. Much of the current work addresses the use of coal-water fuel (CWF) in diesel and turbines, although there is some work with dry coal feed and other coal fuels. Both the diesel and gas turbine portions of the program include proof-of-concept and support projects. Specific highlights of the program include: engine tests and economic analyses have shown that CWF can replace 70 percent of the diesel oil used in the duty cycle of a typical main-line locomotive; A. D. Little and Cooper-Bessemer completed a system and economic study of coal-fueled diesel engines for modular power and industrial cogeneration markets. The coal-fueled diesel was found to be competitive at fuel oil prices of $5.50 per million British thermal units (MBtu); Over 200 hours of testing have been completed using CWF in full-scale, single-cylinder diesel engines. Combustion efficiencies have exceeded 99 percent; Both CWF and dry coal fuel forms can be burned in short residence time in-line combustors and in off-base combustors with a combustion efficiency of over 99 percent; Rich/lean combustion systems employed by the three major DOE contractors have demonstrated low NO(sub x) emissions levels; Contractors have also achieved promising results for controlling sulfur oxide (SO(sub x)) emissions using calcium-based sorbents; Slagging combustors have achieved between 65 and 95 percent slag capture, which will limit particulate loading on pre-turbine cleanup devices. For many of the gas turbine and diesel applications emission standards do not exist. Our goal is to develop coal-fueled diesels and gas turbines that not only meet all applicable emission standards that do exist, but also are capable of meeting possible future standards.

  3. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>20090712 Ge Mingjun(General Institution of Mineral Exploration & Development in Qiqihaer of Heilongjiang Province,Qiqihaer 161006,China) Application of Emulsified Diesel Oil Drilling Fluid in Under-Balanced Drilling(Exploration Engineering(Rock & Soil Drilling and Tunneling),ISSN1672-7428,CN11-5063/TD,34(11),2007,p.43-45,1 illus.,2 tables,4 refs.)

  4. Engineering Ontologies

    OpenAIRE

    Borst, Pim; Akkermans, Hans; Top, Jan

    1997-01-01

    We analyse the construction as well as the role of ontologies in knowledge sharing and reuse for complex industrial applications. In this article, the practical use of ontologies in large-scale applications not restricted to knowledge-based systems is demonstrated, for the domain of engineering systems modelling, simulation and design. A general and formal ontology, called PHYSSYS, for dynamic physical systems is presented and its structuring principles are discussed. We show how the PHYSSYS ...

  5. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>20072985 Bai Mingzhou(Beijing Jiaotong University,Beijing 100044,China);Du Yongqiang Study on Application Technology of Geology Horizontal Drilling in Qiyueshan Tunnel at Yiwan Railway(Exploration Engineering(Rock & Soil Drilling and Tunneling),ISSN1672-7428,CN11-5063/TD,33(4),2006,p.59-61,1 table,3 refs.)Key words:tunnels,horizontal drilling

  6. Web Engineering

    Energy Technology Data Exchange (ETDEWEB)

    White, Bebo

    2003-06-23

    Web Engineering is the application of systematic, disciplined and quantifiable approaches to development, operation, and maintenance of Web-based applications. It is both a pro-active approach and a growing collection of theoretical and empirical research in Web application development. This paper gives an overview of Web Engineering by addressing the questions: (a) why is it needed? (b) what is its domain of operation? (c) how does it help and what should it do to improve Web application development? and (d) how should it be incorporated in education and training? The paper discusses the significant differences that exist between Web applications and conventional software, the taxonomy of Web applications, the progress made so far and the research issues and experience of creating a specialization at the master's level. The paper reaches a conclusion that Web Engineering at this stage is a moving target since Web technologies are constantly evolving, making new types of applications possible, which in turn may require innovations in how they are built, deployed and maintained.

  7. Engineering sustainable development

    Energy Technology Data Exchange (ETDEWEB)

    Deitz, D.

    1996-05-01

    This article describes how engineers are forming alliances on the job, in communities, and in international organizations to accelerate economic development while they preserve resources and the environment. Despite the end of the Cold War and the rapid economic development in Asia and Latin America, anxiety abounds as the 21st century dawns. The growth rate of the world`s population remains frighteningly high, and the Earth`s atmosphere appears endangered. Even rays of hope, such as the surge in China`s and India`s economies, cast a shadow on the future by threatening to deplete natural resources even further. In the face of such overwhelming conditions, individual effort may seem futile. There are signs, however, that people are joining forces to do what they can within the limits of what is technologically and economically possible. Although many of them are driven by idealism, a good number are participating to make business more efficient and profitable as well as to enhance their nation`s industrial competitiveness. Their model for change and growth is one that doesn`t endanger the environment--a concept that has come to be known as sustainable development. In the process, engineers are leaving the isolation of their laboratories and individual disciplines to educate, invent, inspire, and join forces with other engineers, community groups, environmentalists, business and labor leaders, and government officials. One sign that such collaborative efforts are succeeding--in addition to the tangible results--is the evolution in thinking about sustainable development, as it applies both to today`s world and to future generations.

  8. Internet Search Engines

    OpenAIRE

    Fatmaa El Zahraa Mohamed Abdou

    2004-01-01

    A general study about the internet search engines, the study deals main 7 points; the differance between search engines and search directories, components of search engines, the percentage of sites covered by search engines, cataloging of sites, the needed time for sites appearance in search engines, search capabilities, and types of search engines.

  9. Internet Search Engines

    Directory of Open Access Journals (Sweden)

    Fatmaa El Zahraa Mohamed Abdou

    2004-09-01

    Full Text Available A general study about the internet search engines, the study deals main 7 points; the differance between search engines and search directories, components of search engines, the percentage of sites covered by search engines, cataloging of sites, the needed time for sites appearance in search engines, search capabilities, and types of search engines.

  10. Biomaterials & scaffolds for tissue engineering

    Directory of Open Access Journals (Sweden)

    Fergal J. O'Brien

    2011-03-01

    Full Text Available Every day thousands of surgical procedures are performed to replace or repair tissue that has been damaged through disease or trauma. The developing field of tissue engineering (TE aims to regenerate damaged tissues by combining cells from the body with highly porous scaffold biomaterials, which act as templates for tissue regeneration, to guide the growth of new tissue. This article describes the functional requirements, and types, of materials used in developing state of the art of scaffolds for tissue engineering applications. Furthermore, it describes the challenges and where future research and direction is required in this rapidly advancing field.

  11. Growth Disorders

    Science.gov (United States)

    ... because their parents are. But some children have growth disorders. Growth disorders are problems that prevent children from developing ... or other features. Very slow or very fast growth can sometimes signal a gland problem or disease. ...

  12. Microprocessor engineering

    CERN Document Server

    Holdsworth, B

    2013-01-01

    Microprocessor Engineering provides an insight in the structures and operating techniques of a small computer. The book is comprised of 10 chapters that deal with the various aspects of computing. The first two chapters tackle the basic arithmetic and logic processes. The third chapter covers the various memory devices, both ROM and RWM. Next, the book deals with the general architecture of microprocessor. The succeeding three chapters discuss the software aspects of machine operation, while the last remaining three chapters talk about the relationship of the microprocessor with the outside wo

  13. Security Engineering

    Science.gov (United States)

    2012-01-31

    attacks cannot be completely addressed by traditional perimeter security solutions [ Wulf and Jones, 2009], as they have been in the past. A new...the mainstay of the current cyber security solution space [ Wulf and Jones, 2009]. This has enabled the system engineering and security communities...Number: H98230-08-D-0171 DO 002 TO 002 RT 028 Report No. SERC-2012-TR-028 January 31, 2012 UNCLASSIFIED 37 W. A. Wulf and A. K. Jones, Reflections on cyber security, Science Magazine, vol. 326, 2009, pp. 943-944.

  14. EXPLORATION ENGINEERING

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    <正>20122758 Chen Huiming ( No.8 Geology Team of Fujian Province,Longyan 364000,China ) Application Research on Drilling Technology Process Combination for Deep Explora-tion in an Iron Mine of Fujian Province ( Exploration Engineering,ISSN1672-7428,CN11-5063 / TD,38 ( 9 ), 2011,p.6-9,8ta-bles,6refs. ) Key words:drilling in complicated formation According to the drilling technical problems in deep complex formations of the ironmine surrounding Makeng of Fujian Province ,

  15. 40 CFR 89.610 - Maintenance instructions, warranties, emission labeling.

    Science.gov (United States)

    2010-07-01

    ... engine imported pursuant to § 89.605 or § 89.609, ICIs must furnish with each nonroad engine a list of... admission pursuant to § 89.605(a) or § 89.609(b). (b) Warranties. (1) ICIs must submit to the Engine... required by this section prior to importing nonroad engines under this subpart. (2) ICIs must provide...

  16. VI Latin American Congress on Biomedical Engineering

    CERN Document Server

    Hadad, Alejandro

    2015-01-01

    This volume presents the proceedings of the CLAIB 2014, held in Paraná, Entre Ríos, Argentina 29, 30 & 31 October 2014. The proceedings, presented by the Regional Council of Biomedical Engineering for Latin America (CORAL) offer research findings, experiences and activities between institutions and universities to develop Bioengineering, Biomedical Engineering and related sciences. The conferences of the American Congress of Biomedical Engineering are sponsored by the International Federation for Medical and Biological Engineering (IFMBE), Society for Engineering in Biology and Medicine (EMBS) and the Pan American Health Organization (PAHO), among other organizations and international agencies and bringing together scientists, academics and biomedical engineers in Latin America and other continents in an environment conducive to exchange and professional growth. The Topics include: - Bioinformatics and Computational Biology - Bioinstrumentation; Sensors, Micro and Nano Technologies - Biomaterials, Tissu...

  17. VII Latin American Congress on Biomedical Engineering

    CERN Document Server

    Bustamante, John; Sierra, Daniel

    2017-01-01

    This volume presents the proceedings of the CLAIB 2016, held in Bucaramanga, Santander, Colombia, 26, 27 & 28 October 2016. The proceedings, presented by the Regional Council of Biomedical Engineering for Latin America (CORAL), offer research findings, experiences and activities between institutions and universities to develop Bioengineering, Biomedical Engineering and related sciences. The conferences of the American Congress of Biomedical Engineering are sponsored by the International Federation for Medical and Biological Engineering (IFMBE), Society for Engineering in Biology and Medicine (EMBS) and the Pan American Health Organization (PAHO), among other organizations and international agencies to bring together scientists, academics and biomedical engineers in Latin America and other continents in an environment conducive to exchange and professional growth.

  18. Nano surface engineering and remanufacture engineering

    Institute of Scientific and Technical Information of China (English)

    XU Bin-shi

    2004-01-01

    Nano surface engineering and remanufacture engineering are introduced, and the relationship between them is set forth. It points out the superiority of nano surface engineering to the traditional one, and reveals the advantages of remanufacture engineering. Taking some nano surface techniques as samples, such as nano-materials brush electroplating, nano-materials thermal spraying and nano-materials self-repairing antifriction additive technology, it shows the applications of nano surface engineering technology to remanufacturing mechanical parts.

  19. Springer Handbook of Crystal Growth

    CERN Document Server

    Dhanaraj, Govindhan; Prasad, Vishwanath; Dudley, Michael

    2010-01-01

    Over the years, many successful attempts have been made to describe the art and science of crystal growth. Most modern advances in semiconductor and optical devices would not have been possible without the development of many elemental, binary, ternary, and other compound crystals of varying properties and large sizes. The objective of the Springer Handbook of Crystal Growth is to present state-of-the-art knowledge of both bulk and thin-film crystal growth. The goal is to make readers understand the basics of the commonly employed growth processes, materials produced, and defects generated. Almost 100 leading scientists, researchers, and engineers from 22 different countries from academia and industry have been selected to write chapters on the topics of their expertise. They have written 52 chapters on the fundamentals of bulk crystal growth from the melt, solution, and vapor, epitaxial growth, modeling of growth processes and defects, techniques of defect characterization as well as some contemporary specia...

  20. Scaffolds in Tendon Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Umile Giuseppe Longo

    2012-01-01

    Full Text Available Tissue engineering techniques using novel scaffold materials offer potential alternatives for managing tendon disorders. Tissue engineering strategies to improve tendon repair healing include the use of scaffolds, growth factors, cell seeding, or a combination of these approaches. Scaffolds have been the most common strategy investigated to date. Available scaffolds for tendon repair include both biological scaffolds, obtained from mammalian tissues, and synthetic scaffolds, manufactured from chemical compounds. Preliminary studies support the idea that scaffolds can provide an alternative for tendon augmentation with an enormous therapeutic potential. However, available data are lacking to allow definitive conclusion on the use of scaffolds for tendon augmentation. We review the current basic science and clinical understanding in the field of scaffolds and tissue engineering for tendon repair.

  1. Regenerative engineering

    CERN Document Server

    Laurencin, Cato T

    2013-01-01

    Regenerative Engineering: The Future of Medicine Saadiq F. El-Amin III , MD , PhD; Joylene W.L. Thomas, MD ; Ugonna N. Ihekweazu, MD ; Mia D. Woods, MS; and Ashim Gupta, MSCell Biology Gloria Gronowicz, PhD and Karen Sagomonyants, DMDStem Cells and Tissue Regeneration Kristen Martins-Taylor, PhD; Xiaofang Wang, MD , PhD; Xue-Jun Li, PhD; and Ren-He Xu, MD , PhDIntroduction to Materials Science Sangamesh G. Kumbar, PhD and Cato T. Laurencin, MD , PhDBiomaterials A. Jon Goldberg, PhD and Liisa T. Kuhn, PhDIn Vitro Assessment of Cell-Biomaterial Interactions Yong Wang, PhDHost Response to Biomate

  2. Engineering electromagnetics

    CERN Document Server

    Thomas, David T; Hartnett, James P; Hughes, William F

    1973-01-01

    The applications involving electromagnetic fields are so pervasive that it is difficult to estimate their contribution to the industrial output: generation of electricity, power transmission lines, electric motors, actuators, relays, radio, TV and microwave transmission and reception, magnetic storage, and even the mundane little magnet used to hold a paper note on the refrigerator are all electromagnetic in nature. One would be hard pressed to find a device that works without relaying on any electromagnetic principle or effect. This text provides a good theoretical understanding of the electromagnetic field equations but also treats a large number of applications. In fact, no topic is presented unless it is directly applicable to engineering design or unless it is needed for the understanding of another topic. In electrostatics, for example, the text includes discussions of photocopying, ink-jet printing, electrostatic separation and deposition, sandpaper production, paint spraying, and powder coating. In ma...

  3. Engineering viscoelasticity

    CERN Document Server

    Gutierrez-Lemini, Danton

    2014-01-01

    Engineering Viscoelasticity covers all aspects of the thermo- mechanical response of viscoelastic substances that a practitioner in the field of viscoelasticity would need to design experiments, interpret test data, develop stress-strain models, perform stress analyses, design structural components, and carry out research work. The material in each chapter is developed from the elementary to the advanced, providing the background in mathematics and mechanics that are central to understanding the subject matter being presented. The book examines how viscoelastic materials respond to the application of loads, and provides practical guidelines to use them in the design of commercial, military and industrial applications. This book also: ·         Facilitates conceptual understanding by progressing in each chapter from elementary to challenging material ·         Examines in detail both differential and integral constitutive equations, devoting full chapters to each type and using both forms in ...

  4. Reactor Engineering

    Science.gov (United States)

    Lema, Juan M.; López, Carmen; Eibes, Gemma; Taboada-Puig, Roberto; Moreira, M. Teresa; Feijoo, Gumersindo

    In this chapter, the engineering aspects of processes catalyzed by peroxidases will be presented. In particular, a discussion of the existing technologies that utilize peroxidases for different purposes, such as the removal of recalcitrant compounds or the synthesis of polymers, is analyzed. In the first section, the essential variables controlling the process will be investigated, not only those that are common in any enzymatic system but also those specific to peroxidative reactions. Next, different reactor configurations and operational modes will be proposed, emphasizing their suitability and unsuitability for different systems. Finally, two specific reactors will be described in detail: enzymatic membrane reactors and biphasic reactors. These configurations are especially valuable for the treatment of xenobiotics with high and poor water solubility, respectively.

  5. Collaborative engineering for complex products

    CSIR Research Space (South Africa)

    Erasmus, J

    2015-10-01

    Full Text Available stream_source_info Erasmus_2015.pdf.txt stream_content_type text/plain stream_size 6206 Content-Encoding UTF-8 stream_name Erasmus_2015.pdf.txt Content-Type text/plain; charset=UTF-8 Collaborative engineering... • Only viable means of beneficiating natural resources in SA Current situation Competitiveness of manufacturing in SA has dramatically decreased [1] NIPF: Manufacturing drives employment and growth in the economy [2] IPAP: 16 industry sectors...

  6. Carbon nanotubes in tissue engineering.

    Science.gov (United States)

    Bosi, Susanna; Ballerini, Laura; Prato, Maurizio

    2014-01-01

    As a result of their peculiar features, carbon nanotubes (CNTs) are emerging in many areas of nanotechnology applications. CNT-based technology has been increasingly proposed for biomedical applications, to develop biomolecule nanocarriers, bionanosensors and smart material for tissue engineering purposes. In the following chapter this latter application will be explored, describing why CNTs can be considered an ideal material able to support and boost the growth and the proliferation of many kinds of tissues.

  7. A Survey on Semantic Web Search Engine

    Directory of Open Access Journals (Sweden)

    G.Sudeepthi

    2012-03-01

    Full Text Available The tremendous growth in the volume of data and with the terrific growth of number of web pages, traditional search engines now a days are not appropriate and not suitable anymore. Search engine is the most important tool to discover any information in World Wide Web. Semantic Search Engine is born of traditional search engine to overcome the above problem. The Semantic Web is an extension of the current web in which information is given well-defined meaning. Semantic web technologies are playing a crucial role in enhancing traditional web search, as it is working to create machine readable data. but it will not replace traditional search engine. In this paper we made a brief survey on various promising features of some of the best semantic search engines developed so far and we have discussed the various approaches to semantic search. We have summarized the techniques, advantages of some important semantic web search engines that are developed so far.The most prominent part is that how the semantic search engines differ from the traditional searches and their results are shown by giving a sample query as input

  8. The responsibilities of engineers.

    Science.gov (United States)

    Smith, Justin; Gardoni, Paolo; Murphy, Colleen

    2014-06-01

    Knowledge of the responsibilities of engineers is the foundation for answering ethical questions about the work of engineers. This paper defines the responsibilities of engineers by considering what constitutes the nature of engineering as a particular form of activity. Specifically, this paper focuses on the ethical responsibilities of engineers qua engineers. Such responsibilities refer to the duties acquired in virtue of being a member of a group. We examine the practice of engineering, drawing on the idea of practices developed by philosopher Alasdair MacIntyre, and show how the idea of a practice is important for identifying and justifying the responsibilities of engineers. To demonstrate the contribution that knowledge of the responsibilities of engineers makes to engineering ethics, a case study from structural engineering is discussed. The discussion of the failure of the Sleipner A Platform off the coast of Norway in 1991 demonstrates how the responsibilities of engineers can be derived from knowledge of the nature of engineering and its context.

  9. Reliability Engineering

    CERN Document Server

    Lazzaroni, Massimo

    2012-01-01

    This book gives a practical guide for designers and users in Information and Communication Technology context. In particular, in the first Section, the definition of the fundamental terms according to the international standards are given. Then, some theoretical concepts and reliability models are presented in Chapters 2 and 3: the aim is to evaluate performance for components and systems and reliability growth. Chapter 4, by introducing the laboratory tests, puts in evidence the reliability concept from the experimental point of view. In ICT context, the failure rate for a given system can be

  10. Metabolic Engineering X Conference

    Energy Technology Data Exchange (ETDEWEB)

    Flach, Evan [American Institute of Chemical Engineers

    2015-05-07

    The International Metabolic Engineering Society (IMES) and the Society for Biological Engineering (SBE), both technological communities of the American Institute of Chemical Engineers (AIChE), hosted the Metabolic Engineering X Conference (ME-X) on June 15-19, 2014 at the Westin Bayshore in Vancouver, British Columbia. It attracted 395 metabolic engineers from academia, industry and government from around the globe.

  11. 41 CFR 102-80.135 - Who is a qualified fire protection engineer?

    Science.gov (United States)

    2010-07-01

    ... thorough knowledge and understanding of the principles of physics and chemistry governing fire growth... safety engineering, plus a minimum of 4 years work experience in fire protection engineering. (b) A professional engineer (P.E. or similar designation) registered in Fire Protection Engineering. (c) A...

  12. Environmental engineering education enhancement

    Science.gov (United States)

    Caporali, E.

    2012-04-01

    Since higher education plays a central role in the development of both human beings and modern societies, enhancing social, cultural and economic development, active citizenship, ethical values and expertises for a sustainable growth, environment respectful, the European Commission promotes a wide range of programmes. Among the EC programmes, the TEMPUS - Trans European Mobility Programme for University Studies, with the support of the DG EAC of the European Commission, has contributed to many aspects of general interest for higher education. Curricula harmonization, LifeLong Learning Programme development, ICT use, quality assessment, accreditation, innovation learning methods, growth of networks of institutions trusting each other, are the focused aspects. Such a solid cooperation framework is surely among the main outcomes of the TEMPUS Projects leaded by the University of Firenze UNIFI (Italy), DEREC - Development of Environment and Resources Engineering Curriculum (2005-2008), and its spin-off DEREL - Development of Environment and Resources Engineering Learning (2010-2013), and VICES - Videoconferencing Educational Services (2009-2012). DEREC and DEREL TEMPUS projects, through the co-operation of Universities in Italy, Austria, Germany, Greece, Macedonia, Albania and Serbia, are aimed at the development of first and second level curricula in "Environment and Resources Engineering" at the Ss. Cyril and Methodius University - UKIM Skopje (MK). In the DEREC Project the conditions for offering a joint degree title in the field of Environmental Engineering between UNIFI and UKIM Skopje were fulfilled and a shared educational programme leading to the mutual recognition of degree titles was defined. The DEREL project, as logical continuation of DEREC, is aimed to introduce a new, up-to-date, postgraduate second level curriculum in Environment and Resources Engineering at UKIM Skopje, University of Novi Sad (RS) and Polytechnic University of Tirana (AL). following

  13. Skin tissue engineering.

    Science.gov (United States)

    Mansbridge, Jonathan

    2008-01-01

    The major applications of tissue-engineered skin substitutes are in promoting the healing of acute and chronic wounds. Several approaches have been taken by commercial companies to develop products to address these conditions. Skin substitutes include both acellular and cellular devices. While acellular skin substitutes act as a template for dermal formation, this discussion mainly covers cellular devices. In addressing therapeutic applications in tissue engineering generally, a valuable precursor is an understanding of the mechanism of the underlying pathology. While this is straightforward in many cases, it has not been available for wound healing. Investigation of the mode of action of the tissue-engineered skin substitutes has led to considerable insight into the mechanism of formation, maintenance and treatment of chronic wounds. Four aspects mediating healing are considered here for their mechanism of action: (i) colonization of the wound bed by live fibroblasts in the implant, (ii) the secretion of growth factors, (iii) provision of a suitable substrate for cell migration, particularly keratinocytes and immune cells, and (iv) modification of the immune system by secretion of neutrophil recruiting chemokines. An early event in acute wound healing is an influx of neutrophils that destroy planktonic bacteria. However, if the bacteria are able to form biofilm, they become resistant to neutrophil action and prevent reepithelialization. In this situation the wound becomes chronic. In chronic wounds, fibroblasts show a senescence-like phenotype with decreased secretion of neutrophil chemoattractants that make it more likely that biofilms become established. Treatment of the chronic wounds involves debridement to eliminate biofilm, and the use of antimicrobials. A role of skin substitutes is to provide non-senescent fibroblasts that attract and activate neutrophils to prevent biofilm re-establishment. The emphasis of the conclusion is the importance of preventing

  14. Engineer named Loring Professor

    OpenAIRE

    Nystrom, Lynn A.

    2005-01-01

    Saifur Rahman, Virginia Tech professor of electrical and computer engineering (ECE) and the founding director of Virginia Tech's Northern Virginia Division of the College of Engineering, is the recipient of the Joseph R. Loring Professorship of Electrical and Computer Engineering.

  15. PLA-based foams: tissue engineering

    OpenAIRE

    Velasco Perero, José Ignacio; Antunes, Marcelo de Sousa Pais

    2015-01-01

    Biodegradable porous scaffolds with or without bioactive molecules prepared by clean techniques attract an enormous interest for tissue engineering applications. Scaffolds work as structural support for both cell implantation and growth, favoring the regeneration or formation of new tissue. Scaffold requisites for tissue engineering applications include a proper material selection, which has to be biocompatible and biodegradable and with a good balance of mechanical properties, as...

  16. Green chemical engineering aspects of reactive distillation.

    Science.gov (United States)

    Malone, Michael F; Huss, Robert S; Doherty, Michael F

    2003-12-01

    Reactive or catalytic distillation technology combines chemical synthesis steps with separations by distillation. This combination can lead to intensified, high-efficiency process systems with significant green engineering attributes. New applications and understanding have prompted growth in the use of reactive distillation for a variety of chemical syntheses, especially esterifications and etherifications involving oxygenated hydrocarbons. We describe several applications and the potential and tradeoffs for reactive distillation technology in the context of green engineering principles.

  17. Mod II engine development

    Science.gov (United States)

    Karl, David W.

    1987-01-01

    The Mod II engine, a four-cylinder, automotive Stirling engine utilizing the Siemens-Rinia double-acting concept, was assembled and became operational in January 1986. This paper describes the Mod II engine, its first assembly, and the subsequent development work done on engine components up to the point that engine performance characterization testing took place. Performance data for the engine are included.

  18. Modular Engineering Concept at Novo Nordisk Engineering

    DEFF Research Database (Denmark)

    Moelgaard, Gert; Miller, Thomas Dedenroth

    1997-01-01

    This report describes the concept of a new engineering method at Novo Nordisk Engineering: Modular Engineering (ME). Three tools are designed to support project phases with different levels of detailing and abstraction. ME supports a standard, cross-functional breakdown of projects that facilitates...

  19. Modular Engineering Concept at Novo Nordisk Engineering

    DEFF Research Database (Denmark)

    Moelgaard, Gert; Miller, Thomas Dedenroth

    1997-01-01

    This report describes the concept of a new engineering method at Novo Nordisk Engineering: Modular Engineering (ME). Three tools are designed to support project phases with different levels of detailing and abstraction. ME supports a standard, cross-functional breakdown of projects that facilitates...

  20. Environmental Engineering in Mining Engineering Education

    Science.gov (United States)

    Mahamud-Lopez, Manuel Maria; Menendez-Aguado, Juan Maria

    2005-01-01

    In this paper, the current profile of the environmental engineer and the programming of the subject "Environmental Engineering and Technology" corresponding to the studies of Mining Engineering at the University of Oviedo in Spain, is discussed. Professional profile, student knowledge prior to and following instruction as well as…

  1. Software engineering as an engineering discipline

    Science.gov (United States)

    Freedman, Glenn B.

    1988-01-01

    The purpose of this panel is to explore the emerging field of software engineering from a variety of perspectives: university programs; industry training and definition; government development; and technology transfer. In doing this, the panel will address the issues of distinctions among software engineering, computer science, and computer hardware engineering as they relate to the challenges of large, complex systems.

  2. Engineering Encounters: Blasting off with Engineering

    Science.gov (United States)

    Dare, Emily A.; Childs, Gregory T.; Cannaday, E. Ashley; Roehrig, Gillian H

    2014-01-01

    What better way to engage young students in physical science concepts than to have them engineer flying toy rockets? The integration of engineering into science classrooms is advocated by the "Next Generation Science Standards" (NGSS) and researchers alike (Brophy et al. 2008), as engineering provides: (1) A "real-world…

  3. Engine Test Facility (ETF)

    Data.gov (United States)

    Federal Laboratory Consortium — The Air Force Arnold Engineering Development Center's Engine Test Facility (ETF) test cells are used for development and evaluation testing of propulsion systems for...

  4. Contemporary engineering economics

    CERN Document Server

    Park, Chan S

    2011-01-01

    Contemporary Engineering Economics, 5/e, is intended for undergraduate engineering students taking introductory engineering economics while appealing to the full range of engineering disciplines for which this course is often required: industrial, civil, mechanical, electrical, computer, aerospace, chemical, and manufacturing engineering, as well as engineering technology. This edition has been thoroughly revised and updated while continuing to adopt a contemporary approach to the subject, and teaching, of engineering economics. This text aims not only to build a sound and comprehensive coverage of engineering economics, but also to address key educational challenges, such as student difficulty in developing the analytical skills required to make informed financial decisions.

  5. Advanced Metasearch Engine Technology

    CERN Document Server

    Meng, Weiyi

    2010-01-01

    Among the search tools currently on the Web, search engines are the most well known thanks to the popularity of major search engines such as Google and Yahoo!. While extremely successful, these major search engines do have serious limitations. This book introduces large-scale metasearch engine technology, which has the potential to overcome the limitations of the major search engines. Essentially, a metasearch engine is a search system that supports unified access to multiple existing search engines by passing the queries it receives to its component search engines and aggregating the returned

  6. Growth Econometrics

    OpenAIRE

    JOHNSON, Paul; Steven N. Durlauf; Temple, Johnathan R. W.

    2004-01-01

    This paper provides a survey and synthesis of econometric tools that have been employed to study economic growth. While these tools range across a variety of statistical methods, they are united in the common goals of first, identifying interesting contemporaneous patterns in growth data and second, drawing inferences on long-run economic outcomes from cross-section and temporal variation in growth. We describe the main stylized facts that have motivated the development of growth econometrics...

  7. Cartilage Engineering from Mesenchymal Stem Cells

    Science.gov (United States)

    Goepfert, C.; Slobodianski, A.; Schilling, A. F.; Adamietz, P.; Pörtner, R.

    Mesenchymal progenitor cells known as multipotent mesenchymal stromal cells or mesenchymal stem cells (MSC) have been isolated from various tissues. Since they are able to differentiate along the mesenchymal lineages of cartilage and bone, they are regarded as promising sources for the treatment of skeletal defects. Tissue regeneration in the adult organism and in vitro engineering of tissues is hypothesized to follow the principles of embryogenesis. The embryonic development of the skeleton has been studied extensively with respect to the regulatory mechanisms governing morphogenesis, differentiation, and tissue formation. Various concepts have been designed for engineering tissues in vitro based on these developmental principles, most of them involving regulatory molecules such as growth factors or cytokines known to be the key regulators in developmental processes. Growth factors most commonly used for in vitro cultivation of cartilage tissue belong to the fibroblast growth factor (FGF) family, the transforming growth factor-beta (TGF-β) super-family, and the insulin-like growth factor (IGF) family. In this chapter, in vivo actions of members of these growth factors described in the literature are compared with in vitro concepts of cartilage engineering making use of these growth factors.

  8. 77 FR 76883 - Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality...

    Science.gov (United States)

    2012-12-31

    ... standards, nonroad spark-ignition engines and recreational engines standards, large nonroad diesel engine... and includes emission reductions associated with CAIR, EPA's modeling indicates that the area would... initial matter, EPA notes that the modeling EPA conducted during the rulemaking for the CSAPR...

  9. Thin films for material engineering

    Science.gov (United States)

    Wasa, Kiyotaka

    2016-07-01

    Thin films are defined as two-dimensional materials formed by condensing one by one atomic/molecular/ionic species of matter in contrast to bulk three-dimensional sintered ceramics. They are grown through atomic collisional chemical reaction on a substrate surface. Thin film growth processes are fascinating for developing innovative exotic materials. On the basis of my long research on sputtering deposition, this paper firstly describes the kinetic energy effect of sputtered adatoms on thin film growth and discusses on a possibility of room-temperature growth of cubic diamond crystallites and the perovskite thin films of binary compound PbTiO3. Secondly, high-performance sputtered ferroelectric thin films with extraordinary excellent crystallinity compatible with MBE deposited thin films are described in relation to a possible application for thin-film MEMS. Finally, the present thin-film technologies are discussed in terms of a future material science and engineering.

  10. Using Collaborative Engineering to Inform Collaboration Engineering

    Science.gov (United States)

    Cooper, Lynne P.

    2012-01-01

    Collaboration is a critical competency for modern organizations as they struggle to compete in an increasingly complex, global environment. A large body of research on collaboration in the workplace focuses both on teams, investigating how groups use teamwork to perform their task work, and on the use of information systems to support team processes ("collaboration engineering"). This research essay presents collaboration from an engineering perspective ("collaborative engineering"). It uses examples from professional and student engineering teams to illustrate key differences in collaborative versus collaboration engineering and investigates how challenges in the former can inform opportunities for the latter.

  11. Using Collaborative Engineering to Inform Collaboration Engineering

    Science.gov (United States)

    Cooper, Lynne P.

    2012-01-01

    Collaboration is a critical competency for modern organizations as they struggle to compete in an increasingly complex, global environment. A large body of research on collaboration in the workplace focuses both on teams, investigating how groups use teamwork to perform their task work, and on the use of information systems to support team processes ("collaboration engineering"). This research essay presents collaboration from an engineering perspective ("collaborative engineering"). It uses examples from professional and student engineering teams to illustrate key differences in collaborative versus collaboration engineering and investigates how challenges in the former can inform opportunities for the latter.

  12. Genome scale engineering techniques for metabolic engineering.

    Science.gov (United States)

    Liu, Rongming; Bassalo, Marcelo C; Zeitoun, Ramsey I; Gill, Ryan T

    2015-11-01

    Metabolic engineering has expanded from a focus on designs requiring a small number of genetic modifications to increasingly complex designs driven by advances in genome-scale engineering technologies. Metabolic engineering has been generally defined by the use of iterative cycles of rational genome modifications, strain analysis and characterization, and a synthesis step that fuels additional hypothesis generation. This cycle mirrors the Design-Build-Test-Learn cycle followed throughout various engineering fields that has recently become a defining aspect of synthetic biology. This review will attempt to summarize recent genome-scale design, build, test, and learn technologies and relate their use to a range of metabolic engineering applications.

  13. Biomedical engineering education--status and perspectives.

    Science.gov (United States)

    Magjarevic, Ratko; Zequera Diaz, Martha L

    2014-01-01

    Biomedical Engineering programs are present at a large number of universities all over the world with an increasing trend. New generations of biomedical engineers have to face the challenges of health care systems round the world which need a large number of professionals not only to support the present technology in the health care system but to develop new devices and services. Health care stakeholders would like to have innovative solutions directed towards solving problems of the world growing incidence of chronic disease and ageing population. These new solutions have to meet the requirements for continuous monitoring, support or care outside clinical settlements. Presence of these needs can be tracked through data from the Labor Organization in the U.S. showing that biomedical engineering jobs have the largest growth at the engineering labor market with expected 72% growth rate in the period from 2008-2018. In European Union the number of patents (i.e. innovation) is the highest in the category of biomedical technology. Biomedical engineering curricula have to adopt to the new needs and for expectations of the future. In this paper we want to give an overview of engineering professions in related to engineering in medicine and biology and the current status of BME education in some regions, as a base for further discussions.

  14. The multiple interactions between growth factors and microenvironment in vivo

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Cell, growth factors and extracellular matrices (ECMs) coexist in a dynamic tissue envi- ronment. A knowledge of multiple interactions among them is highly important for effectively raising the biological activities of growth factors, regulating cell life cycle, designing and preparing exogenous mat- rices to control growth factors release in tissue or organ regeneration by engineering means. This paper addresses the characteristics and functions of growth factors, interactions between growth factors and ECMs, the manners and correlative signaling of growth factors acting on cells, and briefly summarizes the biomimetic requisites for controlled release mat- rices, hoping to provide a useful reference for co- rrelative research in tissue engineering.

  15. Combinatorial and high-throughput screening approaches for strain engineering.

    Science.gov (United States)

    Liu, Wenshan; Jiang, Rongrong

    2015-03-01

    Microbes have long been used in the industry to produce valuable biochemicals. Combinatorial engineering approaches, new strain engineering tools derived from inverse metabolic engineering, have started to attract attention in recent years, including genome shuffling, error-prone DNA polymerase, global transcription machinery engineering (gTME), random knockout/overexpression libraries, ribosome engineering, multiplex automated genome engineering (MAGE), customized optimization of metabolic pathways by combinatorial transcriptional engineering (COMPACTER), and library construction of "tunable intergenic regions" (TIGR). Since combinatorial approaches and high-throughput screening methods are fundamentally interconnected, color/fluorescence-based, growth-based, and biosensor-based high-throughput screening methods have been reviewed. We believe that with the help of metabolic engineering tools and new combinatorial approaches, plus effective high-throughput screening methods, researchers will be able to achieve better results on improving microorganism performance under stress or enhancing biochemical yield.

  16. Exo-Skeletal Engine: Novel Engine Concept

    Science.gov (United States)

    Chamis, Cristos C.; Blankson, Isaiah M.

    2004-01-01

    The exo-skeletal engine concept represents a new radical engine technology with the potential to substantially revolutionize engine design. It is an all-composite drum-rotor engine in which conventionally heavy shafts and discs are eliminated and are replaced by rotating casings that support the blades in spanwise compression. Thus the rotating blades are in compression rather than tension. The resulting open channel at the engine centerline has immense potential for jet noise reduction and can also accommodate an inner combined-cycle thruster such as a ramjet. The exo-skeletal engine is described in some detail with respect to geometry, components, and potential benefits. Initial evaluations and results for drum rotors, bearings, and weights are summarized. Component configuration, assembly plan, and potential fabrication processes are also identified. A finite element model of the assembled engine and its major components is described. Preliminary results obtained thus far show at least a 30-percent reduction of engine weight and about a 10-dB noise reduction, compared with a baseline conventional high-bypass-ratio engine. Potential benefits in all aspects of this engine technology are identified and tabulated. Quantitative assessments of potential benefits are in progress.

  17. Studying Engineering Practice

    DEFF Research Database (Denmark)

    Buch, Anders

    2015-01-01

    The study of engineering practices has been the focus of Engineering Studies over the last three decades. Theses studies have used ethnographic and grounded methods in order to investigate engineering practices as they unfold in natural settings - in workplaces and engineering education. However......, engineering studies have not given much attention to conceptually clarifying what should be understood by 'engineering practices' and more precisely account for the composition and organization of the entities and phenomena that make up the practices. This chapter investigates and discusses how a 'practice...... will draw out some methodological consequences and discuss the ramifications of a practice theoretical approach for Engineering Studies....

  18. Studying Engineering Practice

    DEFF Research Database (Denmark)

    Buch, Anders

    2015-01-01

    The study of engineering practices has been the focus of Engineering Studies over the last three decades. Theses studies have used ethnographic and grounded methods in order to investigate engineering practices as they unfold in natural settings - in workplaces and engineering education. However......, engineering studies have not given much attention to conceptually clarifying what should be understood by 'engineering practices' and more precisely account for the composition and organization of the entities and phenomena that make up the practices. This chapter investigates and discusses how a 'practice...... will draw out some methodological consequences and discuss the ramifications of a practice theoretical approach for Engineering Studies....

  19. Fundamental of biomedical engineering

    CERN Document Server

    Sawhney, GS

    2007-01-01

    About the Book: A well set out textbook explains the fundamentals of biomedical engineering in the areas of biomechanics, biofluid flow, biomaterials, bioinstrumentation and use of computing in biomedical engineering. All these subjects form a basic part of an engineer''s education. The text is admirably suited to meet the needs of the students of mechanical engineering, opting for the elective of Biomedical Engineering. Coverage of bioinstrumentation, biomaterials and computing for biomedical engineers can meet the needs of the students of Electronic & Communication, Electronic & Instrumenta

  20. Fostering Creative Engineers

    DEFF Research Database (Denmark)

    Zhou, Chunfang

    2012-01-01

    Recent studies have argued a shift of thinking about engineering practice from a linear conception to a system understanding. The complexity of engineering practice has been thought of as the root of challenges for engineers. Moreover, creativity has been emphasised as one key capability...... that engineering students should master. This paper aims to illustrate deeply why engineering education needs to foster creative students to face the challenges of complex engineering work. So a literature review will be provided by focusing on the necessity of developing creativity in engineering education....... As the literature demonstrates, this paper reveals the understanding of complexity in engineering practice and the roles of creativity in engineering practice. In addition, the barriers to creativity in current engineering education and some implications of pedagogic strategies will be discussed. So this paper...

  1. Effects of Intermediate Ethanol Blends on Legacy Vehicles and Small Non‑Road Engines, Report 1 - Updated

    Energy Technology Data Exchange (ETDEWEB)

    Knoll, Keith [National Renewable Energy Laboratory (NREL); West, Brian H [ORNL; Clark, Wendy [National Renewable Energy Laboratory (NREL); Graves, Ronald L [ORNL; Orban, John [Battelle, Columbus; Przesmitzki, Steve [National Renewable Energy Laboratory (NREL); Theiss, Timothy J [ORNL

    2009-02-01

    In summer 2007, the U.S. Department of Energy (DOE) initiated a test program to evaluate the potential impacts of intermediate ethanol blends on legacy vehicles and other engines. The purpose of the test program is to assess the viability of using intermediate blends as a contributor to meeting national goals in the use of renewable fuels. Through a wide range of experimental activities, DOE is evaluating the effects of E15 and E20--gasoline blended with 15 and 20% ethanol--on tailpipe and evaporative emissions, catalyst and engine durability, vehicle driveability, engine operability, and vehicle and engine materials. This first report provides the results available to date from the first stages of a much larger overall test program. Results from additional projects that are currently underway or in the planning stages are not included in this first report. The purpose of this initial study was to quickly investigate the effects of adding up to 20% ethanol to gasoline on the following: (1) Regulated tailpipe emissions for 13 popular late model vehicles on a drive cycle similar to real-world driving and 28 small non-road engines (SNREs) under certification or typical in use procedures. (2) Exhaust and catalyst temperatures of the same vehicles under more severe conditions. (3) Temperature of key engine components of the same SNREs under certification or typical in-use conditions. (4) Observable operational issues with either the vehicles or SNREs during the course of testing. As discussed in the concluding section of this report, a wide range of additional studies are underway or planned to consider the effects of intermediate ethanol blends on materials, emissions, durability, and driveability of vehicles, as well as impacts on a wider range of nonautomotive engines, including marine applications, snowmobiles, and motorcycles. Section 1 (Introduction) gives background on the test program and describes collaborations with industry and agencies to date. Section 2

  2. Engine Cold Start

    Science.gov (United States)

    2015-09-01

    14. ABSTRACT These fuels were used for testing a GEP 6.5L turbocharged V-8 diesel engine operation in a cold box. This engine architecture is... engines . The U.S. military currently uses petroleum-based jet fuels in diesel engine -powered ground vehicles and is studying the use of alternative jet...to identify a window, or range, of cetane number which would be acceptable to ensure the reliable operation of diesel engine -powered military ground

  3. Software Engineering Guidebook

    Science.gov (United States)

    Connell, John; Wenneson, Greg

    1993-01-01

    The Software Engineering Guidebook describes SEPG (Software Engineering Process Group) supported processes and techniques for engineering quality software in NASA environments. Three process models are supported: structured, object-oriented, and evolutionary rapid-prototyping. The guidebook covers software life-cycles, engineering, assurance, and configuration management. The guidebook is written for managers and engineers who manage, develop, enhance, and/or maintain software under the Computer Software Services Contract.

  4. Kinematic Stirling Engine Performance

    Science.gov (United States)

    Tew, J. R. C.

    1986-01-01

    Computer program developed for analyzing thermodynamic characteristics of kinematic Stirling engine. Computes time-varying piston positions, pressures, and gas temperatures in each of gas-control volumes into which engine working space is divided. Engine performance characterized by calculations of power and efficiency (both indicated and brake). Inputs to code are engine geometrical parameter, engine-operating conditions, and indexes that specify various options available.

  5. Mechanical engineer's handbook

    CERN Document Server

    Marghitu, Dan B

    2001-01-01

    The Mechanical Engineer's Handbook was developed and written specifically to fill a need for mechanical engineers and mechanical engineering students throughout the world. With over 1000 pages, 550 illustrations, and 26 tables the Mechanical Engineer's Handbook is very comprehensive, yet affordable, compact, and durable. The Handbook covers all major areas of mechanical engineering with succinct coverage of the definitions, formulas, examples, theory, proofs, and explanations of all principle subject areas. The Handbook is an essential, practical companion for all mechanic

  6. RL-10 Engines

    Science.gov (United States)

    1963-01-01

    The RL-10 engines were developed by Pratt Whitney and tested by the Marshall Space Flight Center (MSFC). Pictured are MSFC engineers working on the mechanics of the RL-10 engines. Originally developed in 1963 as the first liquid hydrogen-fueled engine to operate successfully in space, the RL-10 engines were used on the second stage (S-IV stage) of the Saturn I launch vehicle.

  7. Knowledge Service Engineering Handbook

    CERN Document Server

    Kantola, Jussi

    2012-01-01

    Covering the emerging field of knowledge service engineering, this groundbreaking handbook outlines how to acquire and utilize knowledge in the 21st century. Drawn on the expertise of the founding faculty member of the world's first university knowledge engineering service department, this book describes what knowledge services engineering means and how it is different from service engineering and service production. Presenting multiple cultural aspects including US, Finnish, and Korean, this handbook provides engineering, systemic, industry, and consumer use viewpoints to knowledge service sy

  8. Correlation between genome reduction and bacterial growth.

    Science.gov (United States)

    Kurokawa, Masaomi; Seno, Shigeto; Matsuda, Hideo; Ying, Bei-Wen

    2016-12-01

    Genome reduction by removing dispensable genomic sequences in bacteria is commonly used in both fundamental and applied studies to determine the minimal genetic requirements for a living system or to develop highly efficient bioreactors. Nevertheless, whether and how the accumulative loss of dispensable genomic sequences disturbs bacterial growth remains unclear. To investigate the relationship between genome reduction and growth, a series of Escherichia coli strains carrying genomes reduced in a stepwise manner were used. Intensive growth analyses revealed that the accumulation of multiple genomic deletions caused decreases in the exponential growth rate and the saturated cell density in a deletion-length-dependent manner as well as gradual changes in the patterns of growth dynamics, regardless of the growth media. Accordingly, a perspective growth model linking genome evolution to genome engineering was proposed. This study provides the first demonstration of a quantitative connection between genomic sequence and bacterial growth, indicating that growth rate is potentially associated with dispensable genomic sequences.

  9. Preliminary Evaluation of Altitude Scaling for Turbofan Engine Ice Crystal Icing

    Science.gov (United States)

    Tsao, Jen-Ching

    2017-01-01

    Preliminary evaluation of altitude scaling for turbofan engine ice crystal icing simulation was conducted during the 2015 LF11 engine icing test campaign in PSL.The results showed that a simplified approach for altitude scaling to simulate the key reference engine ice growth feature and associated icing effects to the engine is possible. But special considerations are needed to address the facility operation limitation for lower altitude engine icing simulation.

  10. Tumor Engineering: The Other Face of Tissue Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Ghajar, Cyrus M; Bissell, Mina J

    2010-03-09

    cancer, the training grounds have largely consisted of small rodents, despite marked differences between human and mouse physiology, or plastic dishes, even though just like our tissues and organs most tumors exist within three-dimensional proteinacious milieus. One could argue that this is comparable to training for a desert war in the arctic. In this special issue of tissue engineering, Fischbach-Teschl and colleagues build a strong case for engineering complex cultures analogous to normal organs to tractably model aspects of the human tumor microenvironment that simply cannot be reproduced with traditional two-dimensional cell culture techniques and that cannot be studied in a controlled fashion in vivo. This idea has gained considerable traction of late as concepts presented and convincingly shown years ago have only now begun to be appreciated. Perhaps, then, it is time to organize those who wish to build complex tumor models to study cancer biology under a common umbrella. Accordingly, we propose that tumor engineering be defined as the construction of complex culture models that recapitulate aspects of the in vivo tumor microenvironment to study the dynamics of tumor development, progression, and therapy on multiple scales. Inherent in this definition is the collaboration that must occur between physical and life scientists to guide the design of patterning techniques, materials, and imaging modalities for the study of cancer from the subcellular to tissue level in physiologically relevant contexts. To date, the most successful tissue engineering approaches have employed methods that recapitulate the composition, architecture, and/or chemical presentation of native tissue. For instance, induction of blood vessel growth for therapeutic purposes has been achieved with sequential release of vascular endothelial growth factor (VEGF) and platelet derived growth factor to induce and stabilize blood vessels. This approach imitates that which occurs during physiological

  11. Multi-Fuel Rotary Engine for General Aviation Aircraft

    Science.gov (United States)

    Jones, C.; Ellis, D. R.; Meng, P. R.

    1983-01-01

    Design studies, conducted for NASA, of Advanced Multi-fuel General Aviation and Commuter Aircraft Rotary Stratified Charge Engines are summarized. Conceptual design studies of an advanced engine sized to provide 186/250 shaft KW/HP under cruise conditions at 7620/25,000 m/ft. altitude were performed. Relevant engine development background covering both prior and recent engine test results of the direct injected unthrottled rotary engine technology, including the capability to interchangeably operate on gasoline, diesel fuel, kerosene, or aviation jet fuel, are presented and related to growth predictions. Aircraft studies, using these resultant growth engines, define anticipated system effects of the performance and power density improvements for both single engine and twin engine airplanes. The calculated results indicate superior system performance and 30 to 35% fuel economy improvement for the Rotary-engine airplanes as compared to equivalent airframe concept designs with current baseline engines. The research and technology activities required to attain the projected engine performance levels are also discussed.

  12. Site systems engineering: Systems engineering management plan

    Energy Technology Data Exchange (ETDEWEB)

    Grygiel, M.L. [Westinghouse Hanford Co., Richland, WA (United States)

    1996-05-03

    The Site Systems Engineering Management Plan (SEMP) is the Westinghouse Hanford Company (WHC) implementation document for the Hanford Site Systems Engineering Policy, (RLPD 430.1) and Systems Engineering Criteria Document and Implementing Directive, (RLID 430.1). These documents define the US Department of Energy (DOE), Richland Operations Office (RL) processes and products to be used at Hanford to implement the systems engineering process at the site level. This SEMP describes the products being provided by the site systems engineering activity in fiscal year (FY) 1996 and the associated schedule. It also includes the procedural approach being taken by the site level systems engineering activity in the development of these products and the intended uses for the products in the integrated planning process in response to the DOE policy and implementing directives. The scope of the systems engineering process is to define a set of activities and products to be used at the site level during FY 1996 or until the successful Project Hanford Management Contractor (PHMC) is onsite as a result of contract award from Request For Proposal DE-RP06-96RL13200. Following installation of the new contractor, a long-term set of systems engineering procedures and products will be defined for management of the Hanford Project. The extent to which each project applies the systems engineering process and the specific tools used are determined by the project`s management.

  13. Handbook of Software Engineering and Knowledge Engineering

    CERN Document Server

    2001-01-01

    This is the first handbook to cover comprehensively both software engineering and knowledge engineering - two important fields that have become interwoven in recent years. Over 60 international experts have contributed to the book. Each chapter has been written in such a way that a practitioner of software engineering and knowledge engineering can easily understand and obtain useful information. Each chapter covers one topic and can be read independently of other chapters, providing both a general survey of the topic and an in-depth exposition of the state of the art.

  14. Biomedical engineering education through global engineering teams.

    Science.gov (United States)

    Scheffer, C; Blanckenberg, M; Garth-Davis, B; Eisenberg, M

    2012-01-01

    Most industrial projects require a team of engineers from a variety of disciplines. The team members are often culturally diverse and geographically dispersed. Many students do not acquire sufficient skills from typical university courses to function efficiently in such an environment. The Global Engineering Teams (GET) programme was designed to prepare students such a scenario in industry. This paper discusses five biomedical engineering themed projects completed by GET students. The benefits and success of the programme in educating students in the field of biomedical engineering are discussed.

  15. Propagation Engineering in Wireless Communications

    CERN Document Server

    Ghasemi, Abdollah; Ghasemi, Farshid

    2012-01-01

    Wireless communications has seen explosive growth in recent decades, in a realm that is both broad and rapidly expanding to include satellite services, navigational aids, remote sensing, telemetering, audio and video broadcasting, high-speed data communications, mobile radio systems and much more. Propagation Engineering in Wireless Communications deals with the basic principles of radiowaves propagation for frequency bands used in radio-communications, offering descriptions of new achievements and newly developed propagation models. The book bridges the gap between theoretical calculations and approaches, and applied procedures needed for advanced radio links design. The primary objective of this two-volume set is to demonstrate the fundamentals, and to introduce propagation phenomena and mechanisms that engineers are likely to encounter in the design and evaluation of radio links of a given type and operating frequency. Volume one covers basic principles, along with tropospheric and ionospheric propagation,...

  16. Cell–scaffold interaction within engineered tissue

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Haiping; Liu, Yuanyuan, E-mail: Yuanyuan_liu@shu.edu.cn; Jiang, Zhenglong; Chen, Weihua; Yu, Yongzhe; Hu, Qingxi

    2014-05-01

    The structure of a tissue engineering scaffold plays an important role in modulating tissue growth. A novel gelatin–chitosan (Gel–Cs) scaffold with a unique structure produced by three-dimensional printing (3DP) technology combining with vacuum freeze-drying has been developed for tissue-engineering applications. The scaffold composed of overall construction, micro-pore, surface morphology, and effective mechanical property. Such a structure meets the essential design criteria of an ideal engineered scaffold. The favorable cell–matrix interaction supports the active biocompatibility of the structure. The structure is capable of supporting cell attachment and proliferation. Cells seeded into this structure tend to maintain phenotypic shape and secreted large amounts of extracellular matrix (ECM) and the cell growth decreased the mechanical properties of scaffold. This novel biodegradable scaffold has potential applications for tissue engineering based upon its unique structure, which acts to support cell growth. - Highlights: • The scaffold is not only for providing a surface for cell residence but also for determining cell phenotype and retaining structural integrity. • The mechanical property of scaffold can be affected by activities of cell. • The scaffold provides a microenvironment for cell attachment, growth, and migration.

  17. Biomedical engineering at UCT - challenges and opportunities.

    Science.gov (United States)

    Douglas, Tania S

    2012-03-02

    The biomedical engineering programme at the University of Cape Town has the potential to address some of South Africa's unique public health challenges and to contribute to growth of the local medical device industry, directly and indirectly, through research activities and postgraduate education. Full realisation of this potential requires engagement with the clinical practice environment and with industry.

  18. R&D Jobs for BS Engineers.

    Science.gov (United States)

    Basta, Nicholas

    1985-01-01

    Outlines opportunities for beginning engineers seeking employment in research and development (R&D). R&D spending growth, underlying factors, job categories, and divisions within an industrial firm are discussed. Above average grades and additional mathematics courses are primary requirements for an R&D position, which may later lead to…

  19. Towards improved scaffolds for bone tissue engineering

    NARCIS (Netherlands)

    Nandakumar, A.

    2012-01-01

    Tissue engineering aims to restore, maintain or improve tissue function of damaged tissues. In a classical set-up, a scaffold functions as a supporting structure and a carrier for growth factors and/or cells. Human mesenchymal stromal cells (hMSCs) have the ability to differentiate into bone, cartil

  20. Single domain antibodies in tissue engineering

    NARCIS (Netherlands)

    Rodrigues, Emilie Dooms

    2014-01-01

    The aim of this thesis is to demonstrate the potential of VHH in tissue engineering applications, with a focus on bone and cartilage tissue regeneration. After a general introduction to this thesis in chapter 1, the selection of VHH targeting growth factors is described in chapter 2. VHH were select

  1. 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…

  2. Engineering Annual Summary 1999

    Energy Technology Data Exchange (ETDEWEB)

    Dimolitsas, S.; Gerich, C.

    2000-04-11

    In 1999, Engineering at Lawrence Livermore National Laboratory faced competing priorities to meet critical project milestones, insistent pressures to restructure internally to promote long-term technological growth, and immediate demands to reassign employees as major projects terminated and new ones emerged. This drive for change occurred among an unprecedented level of turmoil within the nuclear weapons design and manufacturing community. I believe the technical problems were more demanding this year and the environment within which they were accomplished more challenging, pushing us to accomplish more during greater turbulence than any other time in my tenure here. I am pleased to report that we met many key milestones and achieved numerous technological breakthroughs. In the project support areas, demands presented by our customers shifted significantly over the year. In the lasers area, we continued the detailed designs for the over $1 billion National Ignition Facility (NIF) super laser, paving the way for the procurement of components and structures for what is probably the largest high-tech construction project in the world. This work was undertaken in an environment of significant management and structural changes, with increased reporting requirements from the Department of Energy, starting in the middle of 1999. Despite these changes, our technical progress since 1995 has resulted in a 5000-fold improvement in the performance/cost characteristics of NIF--only a factor of 2 away from where we need to get. In the defense area, we delivered the first production unit of the refurbished W87 weapon, on schedule, for eventual delivery to the Air Force. Also in the defense area, we developed and implemented a new philosophy for conducting underground materials testing using expendable containment vessels. This allowed us to increase our test throughput rate six-fold and simultaneously reduce cost by a commensurate amount. The first two tests were conducted with

  3. Career Pathways of Science, Engineering and Technology Research Postgraduates

    Science.gov (United States)

    Giles, Marnie; Ski, Chantal; Vrdoljak, Davorin

    2009-01-01

    Suitably qualified scientists and engineers are essential for research and development, innovation and, in turn, the growth of the economy. Science, engineering and technology skills are therefore necessary for Australia to remain competitive in a global market. This article reports findings from a nationwide study investigating the career…

  4. Engineering Education in Bangladesh--An Indicator of Economic Development

    Science.gov (United States)

    Chowdhury, Harun; Alam, Firoz

    2012-01-01

    Developing nations including Bangladesh are significantly lagging behind the millennium development target due to the lack of science, technology and engineering education. Bangladesh as a least developing country has only 44 engineers per million people. Its technological education and gross domestic product growth are not collinear. Although…

  5. Employability and skill set of newly graduated engineers in India

    OpenAIRE

    Blom, Andreas; Saeki, Hiroshi

    2011-01-01

    Skill shortage remains one of the major constraints to continued growth of the Indian economy. This employer survey seeks to address this knowledge-gap by answering three questions: (i) Which skills do employers consider important when hiring new engineering graduates? (ii) How satisfied are employers with the skills of engineering graduates? and (iii) In which important skills are the eng...

  6. Reliability and safety engineering

    CERN Document Server

    Verma, Ajit Kumar; Karanki, Durga Rao

    2016-01-01

    Reliability and safety are core issues that must be addressed throughout the life cycle of engineering systems. Reliability and Safety Engineering presents an overview of the basic concepts, together with simple and practical illustrations. The authors present reliability terminology in various engineering fields, viz.,electronics engineering, software engineering, mechanical engineering, structural engineering and power systems engineering. The book describes the latest applications in the area of probabilistic safety assessment, such as technical specification optimization, risk monitoring and risk informed in-service inspection. Reliability and safety studies must, inevitably, deal with uncertainty, so the book includes uncertainty propagation methods: Monte Carlo simulation, fuzzy arithmetic, Dempster-Shafer theory and probability bounds. Reliability and Safety Engineering also highlights advances in system reliability and safety assessment including dynamic system modeling and uncertainty management. Cas...

  7. Humanitarian engineering in the engineering curriculum

    Science.gov (United States)

    Vandersteen, Jonathan Daniel James

    There are many opportunities to use engineering skills to improve the conditions for marginalized communities, but our current engineering education praxis does not instruct on how engineering can be a force for human development. In a time of great inequality and exploitation, the desire to work with the impoverished is prevalent, and it has been proposed to adjust the engineering curriculum to include a larger focus on human needs. This proposed curriculum philosophy is called humanitarian engineering. Professional engineers have played an important role in the modern history of power, wealth, economic development, war, and industrialization; they have also contributed to infrastructure, sanitation, and energy sources necessary to meet human need. Engineers are currently at an important point in time when they must look back on their history in order to be more clear about how to move forward. The changing role of the engineer in history puts into context the call for a more balanced, community-centred engineering curriculum. Qualitative, phenomenographic research was conducted in order to understand the need, opportunity, benefits, and limitations of a proposed humanitarian engineering curriculum. The potential role of the engineer in marginalized communities and details regarding what a humanitarian engineering program could look like were also investigated. Thirty-two semi-structured research interviews were conducted in Canada and Ghana in order to collect a pool of understanding before a phenomenographic analysis resulted in five distinct outcome spaces. The data suggests that an effective curriculum design will include teaching technical skills in conjunction with instructing about issues of social justice, social location, cultural awareness, root causes of marginalization, a broader understanding of technology, and unlearning many elements about the role of the engineer and the dominant economic/political ideology. Cross-cultural engineering development

  8. Growth references

    NARCIS (Netherlands)

    Buuren, S. van

    2007-01-01

    A growth reference describes the variation of an anthropometric measurement within a group of individuals. A reference is a tool for grouping and analyzing data and provides a common basis for comparing populations.1 A well known type of reference is the age-conditional growth diagram. The

  9. Extrapituitary growth hormone and growth?

    Science.gov (United States)

    Harvey, Steve; Baudet, Marie-Laure

    2014-09-01

    While growth hormone (GH) is obligatory for postnatal growth, it is not required for a number of growth-without-GH syndromes, such as early embryonic or fetal growth. Instead, these syndromes are thought to be dependent upon local growth factors, rather than pituitary GH. The GH gene is, however, also expressed in many extrapituitary tissues, particularly during early development and extrapituitary GH may be one of the local growth factors responsible for embryonic or fetal growth. Moreover, as the expression of the GH receptor (GHR) gene mirrors that of GH in extrapituitary tissues the actions of GH in early development are likely to be mediated by local autocrine or paracrine mechanisms, especially as extrapituitary GH expression occurs prior to the ontogeny of pituitary somatotrophs or the appearance of GH in the circulation. The extrapituitary expression of pituitary somatotrophs or the appearance of GH in the circulation. The extrapituitary expression of GH in embryos has also been shown to be of functional relevance in a number of species, since the immunoneutralization of endogenous GH or the blockade of GH production is accompanied by growth impairment or cellular apoptosis. The extrapituitary expression of the GH gene also persists in some central and peripheral tissues postnatally, which may reflect its continued functional importance and physiological or pathophysiological significance. The expression and functional relevance of extrapituitary GH, particularly during embryonic growth, is the focus of this brief review.

  10. Service Cart For Engines

    Science.gov (United States)

    Ng, Gim Shek

    1995-01-01

    Cart supports rear-mounted air-cooled engine from Volkswagen or Porsche automobile. One person removes, repairs, tests, and reinstalls engine of car, van, or home-built airplane. Consists of framework of wood, steel, and aluminum components supported by four wheels. Engine lifted from vehicle by hydraulic jack and gently lowered onto waiting cart. Jack removed from under engine. Rear of vehicle raised just enough that engine can be rolled out from under it. Cart easily supports 200-lb engine. Also used to hold transmission. With removable sheet-metal top, cart used as portable seat.

  11. Service Cart For Engines

    Science.gov (United States)

    Ng, Gim Shek

    1995-01-01

    Cart supports rear-mounted air-cooled engine from Volkswagen or Porsche automobile. One person removes, repairs, tests, and reinstalls engine of car, van, or home-built airplane. Consists of framework of wood, steel, and aluminum components supported by four wheels. Engine lifted from vehicle by hydraulic jack and gently lowered onto waiting cart. Jack removed from under engine. Rear of vehicle raised just enough that engine can be rolled out from under it. Cart easily supports 200-lb engine. Also used to hold transmission. With removable sheet-metal top, cart used as portable seat.

  12. Engineer: The Professional Bulletin of Army Engineers

    Science.gov (United States)

    2009-12-01

    Battalion Fort Carson, Colorado Hill, Specialist Kevin O. 576th Engineer Company, 4th Engineer Battalion Fort Carson, Colorado Lawson, Specialist Daniel C...center-to-center of boats. Planking called chess, laid across balks (stringers), provided a roadway 11 feet wide between guardrails. To permit the

  13. When Do Faculty Inputs Matter? A Panel Study of Racial/Ethnic Differences in Engineering Bachelor's Degree Production

    Science.gov (United States)

    Ransom, Tafaya

    2013-01-01

    Science, technology, engineering and mathematics (STEM) fields are widely credited as the primary drivers of economic growth through innovation, with engineering universally identified as especially critical. Yet as other nations have strengthened their engineering talent pools, the United States has struggled to cultivate an engineering workforce…

  14. Using Polymeric Scaffolds for Vascular Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Alida Abruzzo

    2014-01-01

    Full Text Available With the high occurrence of cardiovascular disease and increasing numbers of patients requiring vascular access, there is a significant need for small-diameter (<6 mm inner diameter vascular graft that can provide long-term patency. Despite the technological improvements, restenosis and graft thrombosis continue to hamper the success of the implants. Vascular tissue engineering is a new field that has undergone enormous growth over the last decade and has proposed valid solutions for blood vessels repair. The goal of vascular tissue engineering is to produce neovessels and neoorgan tissue from autologous cells using a biodegradable polymer as a scaffold. The most important advantage of tissue-engineered implants is that these tissues can grow, remodel, rebuild, and respond to injury. This review describes the development of polymeric materials over the years and current tissue engineering strategies for the improvement of vascular conduits.

  15. Aloe Vera for Tissue Engineering Applications.

    Science.gov (United States)

    Rahman, Shekh; Carter, Princeton; Bhattarai, Narayan

    2017-02-14

    Aloe vera, also referred as Aloe barbadensis Miller, is a succulent plant widely used for biomedical, pharmaceutical and cosmetic applications. Aloe vera has been used for thousands of years. However, recent significant advances have been made in the development of aloe vera for tissue engineering applications. Aloe vera has received considerable attention in tissue engineering due to its biodegradability, biocompatibility, and low toxicity properties. Aloe vera has been reported to have many biologically active components. The bioactive components of aloe vera have effective antibacterial, anti-inflammatory, antioxidant, and immune-modulatory effects that promote both tissue regeneration and growth. The aloe vera plant, its bioactive components, extraction and processing, and tissue engineering prospects are reviewed in this article. The use of aloe vera as tissue engineering scaffolds, gels, and films is discussed, with a special focus on electrospun nanofibers.

  16. Aloe Vera for Tissue Engineering Applications

    Directory of Open Access Journals (Sweden)

    Shekh Rahman

    2017-02-01

    Full Text Available Aloe vera, also referred as Aloe barbadensis Miller, is a succulent plant widely used for biomedical, pharmaceutical and cosmetic applications. Aloe vera has been used for thousands of years. However, recent significant advances have been made in the development of aloe vera for tissue engineering applications. Aloe vera has received considerable attention in tissue engineering due to its biodegradability, biocompatibility, and low toxicity properties. Aloe vera has been reported to have many biologically active components. The bioactive components of aloe vera have effective antibacterial, anti-inflammatory, antioxidant, and immune-modulatory effects that promote both tissue regeneration and growth. The aloe vera plant, its bioactive components, extraction and processing, and tissue engineering prospects are reviewed in this article. The use of aloe vera as tissue engineering scaffolds, gels, and films is discussed, with a special focus on electrospun nanofibers.

  17. Advanced Natural Gas Reciprocating Engine(s)

    Energy Technology Data Exchange (ETDEWEB)

    Pike, Edward

    2014-03-31

    The objective of the Cummins ARES program, in partnership with the US Department of Energy (DOE), is to develop advanced natural gas engine technologies that increase engine system efficiency at lower emissions levels while attaining lower cost of ownership. The goals of the project are to demonstrate engine system achieving 50% Brake Thermal Efficiency (BTE) in three phases, 44%, 47% and 50% (starting baseline efficiency at 36% BTE) and 0.1 g/bhp-hr NOx system out emissions (starting baseline NOx emissions at 2 – 4 g/bhp-hr NOx). Primary path towards above goals include high Brake Mean Effective Pressure (BMEP), improved closed cycle efficiency, increased air handling efficiency and optimized engine subsystems. Cummins has successfully demonstrated each of the phases of this program. All targets have been achieved through application of a combined set of advanced base engine technologies and Waste Heat Recovery from Charge Air and Exhaust streams, optimized and validated on the demonstration engine and other large engines. The following architectures were selected for each Phase: Phase 1: Lean Burn Spark Ignited (SI) Key Technologies: High Efficiency Turbocharging, Higher Efficiency Combustion System. In production on the 60/91L engines. Over 500MW of ARES Phase 1 technology has been sold. Phase 2: Lean Burn Technology with Exhaust Waste Heat Recovery (WHR) System Key Technologies: Advanced Ignition System, Combustion Improvement, Integrated Waste Heat Recovery System. Base engine technologies intended for production within 2 to 3 years Phase 3: Lean Burn Technology with Exhaust and Charge Air Waste Heat Recovery System Key Technologies: Lower Friction, New Cylinder Head Designs, Improved Integrated Waste Heat Recovery System. Intended for production within 5 to 6 years Cummins is committed to the launch of next generation of large advanced NG engines based on ARES technology to be commercialized worldwide.

  18. 40 CFR 90.906 - Manufacturer-owned exemption and precertification exemption.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Manufacturer-owned exemption and... KILOWATTS Exclusion and Exemption of Nonroad Engines from Regulations § 90.906 Manufacturer-owned exemption and precertification exemption. (a) Any manufacturer owned nonroad engine, as defined by § 90.902,...

  19. Indirect Contributions of AM Fungi and Soil Aggregation to Plant Growth and Protection

    Science.gov (United States)

    Soil ecological and biological engineering are processes by which soil organisms modify their physiochemical environment resulting indirectly to enhancements in plant growth. The formation and stabilization of soil aggregates is an example biologically-mediated engineering. For soil organisms, wate...

  20. Sonochemistry: Science and Engineering.

    Science.gov (United States)

    Pokhrel, Nimesh; Vabbina, Phani Kiran; Pala, Nezih

    2016-03-01

    Sonochemistry offers a simple route to nanomaterial synthesis with the application of ultrasound. The tiny acoustic bubbles, produced by the propagating sound wave, enclose an incredible facility where matter interact among at energy as high as 13 eV to spark extraordinary chemical reactions. Within each period - formation, growth and collapse of bubbles, lies a coherent phase of material formation. This effective yet highly localized method has facilitated synthesis of various chemical and biological compounds featuring unique morphology and intrinsic property. The benign processing lends to synthesis without any discrimination towards a certain group of material, or the substrates where they are grown. As a result, new and improved applications have evolved to reach out various field of science and technology and helped engineer new and better devices. Along with the facile processing and notes on the essence of sonochemistry, in this comprehensive review, we discuss the individual and mutual effect of important input parameters on the nanomaterial synthesis process as a start to help understand the underlying mechanism. Secondly, an objective discussion of the diversely synthesized nanomaterial follows to divulge the easiness imparted by sonochemistry, which finally blends into the discussion of their applications and outreach.

  1. Ice Engineering Research Area

    Data.gov (United States)

    Federal Laboratory Consortium — Refrigerated Physical Modeling of Waterways in a Controlled EnvironmentThe Research Area in the Ice Engineering Facility at the Cold Regions Research and Engineering...

  2. Concrete construction engineering handbook

    CERN Document Server

    Nawy, Edward G

    2008-01-01

    Provides coverage of concrete construction engineering and technology. This work features discussions focusing on: the advances in engineered concrete materials; reinforced concrete construction; specialized construction techniques; and, design recommendations for high performance.

  3. Engineer receives Worcester professorship

    OpenAIRE

    Nystrom, Lynn A.

    2005-01-01

    Jeffrey H. Reed, Virginia Tech professor of electrical and computer engineering (ECE), is the new recipient of the Willis G. Worcester Professorship of Electrical and Computer Engineering, traditionally awarded to a leading researcher.

  4. Engineering Knowledge Management

    DEFF Research Database (Denmark)

    Wallace, Ken M.; Ahmed, Saeema; Bracewell, Rob

    2005-01-01

    The need to improve engineering knowledge management is driven by the current challenges facing manufacturing organisations in the emerging global economy and, in particular by the important role knowledge plays in the engineering design process. Industrial organisations are facing increasing...

  5. Social engineering attack framework

    CSIR Research Space (South Africa)

    Mouton, F

    2014-07-01

    Full Text Available link. A social engineering attack targets this weakness by; using various manipulation techniques in order to elicit sensitive; information. The field of social engineering is still in its infancy; stages with regards to formal definitions and attack...

  6. Chemical Engineering Education Revisited.

    Science.gov (United States)

    Theodore, Louis

    1978-01-01

    The opinion is presented that chemical engineering education seems to emphasize the professor's research and/or professional interests with little regard for the real needs of the student who intends to become a practicing engineer. (BB)

  7. Biochemical Engineering Fundamentals

    Science.gov (United States)

    Bailey, J. E.; Ollis, D. F.

    1976-01-01

    Discusses a biochemical engineering course that is offered as part of a chemical engineering curriculum and includes topics that influence the behavior of man-made or natural microbial or enzyme reactors. (MLH)

  8. Shaped Crystal Growth

    Science.gov (United States)

    Tatartchenko, Vitali A.

    Crystals of specified shape and size (shaped crystals) with controlled crystal growth (SCG) defect and impurity structure have to be grown for the successful development of modern engineering. Since the 1950s many hundreds of papers and patents concerned with shaped growth have been published. In this chapter, we do not try to enumerate the successful applications of shaped growth to different materials but rather to carry out a fundamental physical and mathematical analysis of shaping as well as the peculiarities of shaped crystal structures. Four main techniques, based on which the lateral surface can be shaped without contact with the container walls, are analyzed: the Czochralski technique (CZT), the Verneuil technique (VT), the floating zone technique (FZT), and technique of pulling from shaper (TPS). Modifications of these techniques are analyzed as well. In all these techniques the shape of the melt meniscus is controlled by surface tension forces, i.e., capillary forces, and here they are classified as capillary shaping techniques (CST). We look for conditions under which the crystal growth process in each CST is dynamically stable. Only in this case are all perturbations attenuated and a crystal of constant cross section shaping technique (CST) grown without any special regulation. The dynamic stability theory of the crystal growth process for all CST is developed on the basis of Lyapunov's dynamic stability theory. Lyapunov's equations for the crystal growth processes follow from fundamental laws. The results of the theory allow the choice of stable regimes for crystal growth by all CST as well as special designs of shapers in TPS. SCG experiments by CZT, VT, and FZT are discussed but the main consideration is given to TPS. Shapers not only allow crystal of very complicated cross section to be grown but provide a special distribution of impurities. A history of TPS is provided later in the chapter, because it can only be described after explanation of the

  9. Growth Stimulants

    OpenAIRE

    Matthews, Nyle J.

    1989-01-01

    A tiny pellet inserted under the skin of a calf's ear may increase weight gains as much as 15 to 20 percent. This same result would take years to accomplish through breeding and selection. These tiny pellets are growth stimulants. They are made of hormones that are constructed to slowly release minute amounts into the blood stream that stimulate the animal to produce natural body hormones. One of these hormones is a growth hormone. It regulates the rate of growth of the animal. Increasing the...

  10. Biomechanics and mechanobiology in functional tissue engineering

    Science.gov (United States)

    Guilak, Farshid; Butler, David L.; Goldstein, Steven A.; Baaijens, Frank P.T.

    2014-01-01

    The field of tissue engineering continues to expand and mature, and several products are now in clinical use, with numerous other preclinical and clinical studies underway. However, specific challenges still remain in the repair or regeneration of tissues that serve a predominantly biomechanical function. Furthermore, it is now clear that mechanobiological interactions between cells and scaffolds can critically influence cell behavior, even in tissues and organs that do not serve an overt biomechanical role. Over the past decade, the field of “functional tissue engineering” has grown as a subfield of tissue engineering to address the challenges and questions on the role of biomechanics and mechanobiology in tissue engineering. Originally posed as a set of principles and guidelines for engineering of load-bearing tissues, functional tissue engineering has grown to encompass several related areas that have proven to have important implications for tissue repair and regeneration. These topics include measurement and modeling of the in vivo biomechanical environment; quantitative analysis of the mechanical properties of native tissues, scaffolds, and repair tissues; development of rationale criteria for the design and assessment of engineered tissues; investigation of the effects biomechanical factors on native and repair tissues, in vivo and in vitro; and development and application of computational models of tissue growth and remodeling. Here we further expand this paradigm and provide examples of the numerous advances in the field over the past decade. Consideration of these principles in the design process will hopefully improve the safety, efficacy, and overall success of engineered tissue replacements. PMID:24818797

  11. 40 CFR 90.116 - Certification procedure-determining engine displacement, engine class, and engine families.

    Science.gov (United States)

    2010-07-01

    ... engine displacement, engine class, and engine families. 90.116 Section 90.116 Protection of Environment...-IGNITION ENGINES AT OR BELOW 19 KILOWATTS Emission Standards and Certification Provisions § 90.116 Certification procedure—determining engine displacement, engine class, and engine families. (a)...

  12. Mechanical engineering education

    CERN Document Server

    Davim, J Paulo

    2012-01-01

    Mechanical Engineering is defined nowadays as a discipline "which involves the application of principles of physics, design, manufacturing and maintenance of mechanical systems". Recently, mechanical engineering has also focused on some cutting-edge subjects such as nanomechanics and nanotechnology, mechatronics and robotics, computational mechanics, biomechanics, alternative energies, as well as aspects related to sustainable mechanical engineering.This book covers mechanical engineering higher education with a particular emphasis on quality assurance and the improvement of academic

  13. Biomedical Engineering Laboratory

    Science.gov (United States)

    2007-11-02

    The Masters of Engineering program with concentration in Biomedical Engineering at Tennessee State University was established in fall 2000. Under... biomedical engineering . The lab is fully equipped with 10 Pentium5-based, 2 Pentium4-based laptops for mobile experiments at remote locations, 8 Biopac...students (prospective graduate students in biomedical engineering ) are regularly using this lab. This summer, 8 new prospective graduate students

  14. Biomedical engineering fundamentals

    CERN Document Server

    Bronzino, Joseph D

    2014-01-01

    Known as the bible of biomedical engineering, The Biomedical Engineering Handbook, Fourth Edition, sets the standard against which all other references of this nature are measured. As such, it has served as a major resource for both skilled professionals and novices to biomedical engineering.Biomedical Engineering Fundamentals, the first volume of the handbook, presents material from respected scientists with diverse backgrounds in physiological systems, biomechanics, biomaterials, bioelectric phenomena, and neuroengineering. More than three dozen specific topics are examined, including cardia

  15. Unified Engineering Software System

    Science.gov (United States)

    Purves, L. R.; Gordon, S.; Peltzman, A.; Dube, M.

    1989-01-01

    Collection of computer programs performs diverse functions in prototype engineering. NEXUS, NASA Engineering Extendible Unified Software system, is research set of computer programs designed to support full sequence of activities encountered in NASA engineering projects. Sequence spans preliminary design, design analysis, detailed design, manufacturing, assembly, and testing. Primarily addresses process of prototype engineering, task of getting single or small number of copies of product to work. Written in FORTRAN 77 and PROLOG.

  16. Electronics engineer's reference book

    CERN Document Server

    Turner, L W

    1976-01-01

    Electronics Engineer's Reference Book, 4th Edition is a reference book for electronic engineers that reviews the knowledge and techniques in electronics engineering and covers topics ranging from basics to materials and components, devices, circuits, measurements, and applications. This edition is comprised of 27 chapters; the first of which presents general information on electronics engineering, including terminology, mathematical equations, mathematical signs and symbols, and Greek alphabet and symbols. Attention then turns to the history of electronics; electromagnetic and nuclear radiatio

  17. Earthquake engineering research: 1982

    Science.gov (United States)

    The Committee on Earthquake Engineering Research addressed two questions: What progress has research produced in earthquake engineering and which elements of the problem should future earthquake engineering pursue. It examined and reported in separate chapters of the report: Applications of Past Research, Assessment of Earthquake Hazard, Earthquake Ground Motion, Soil Mechanics and Earth Structures, Analytical and Experimental Structural Dynamics, Earthquake Design of Structures, Seismic Interaction of Structures and Fluids, Social and Economic Aspects, Earthquake Engineering Education, Research in Japan.

  18. Battery systems engineering

    CERN Document Server

    Rahn, Christopher D

    2012-01-01

    A complete all-in-one reference on the important interdisciplinary topic of Battery Systems Engineering Focusing on the interdisciplinary area of battery systems engineering, this book provides the background, models, solution techniques, and systems theory that are necessary for the development of advanced battery management systems. It covers the topic from the perspective of basic electrochemistry as well as systems engineering topics and provides a basis for battery modeling for system engineering of electric and hybrid electric vehicle platforms. This original

  19. Systems engineering simplified

    CERN Document Server

    Cloutier, Robert; Bone, Mary Alice

    2015-01-01

    IntroductionOverviewDiscussion of Common TerminologyThe Case for Systems EngineeringA Brief History of Systems EngineeringSystem ExamplesSummaryThe System Life CycleManaging System Development-The Vee ModelSystem ProductionSystem Utilization and SupportSystem Retirement and DisposalOther Systems Engineering Development ModelsSpiral ModelAgile Model for Systems EngineeringSystem of InterestAbstraction and DecompositionIntegrationDeveloping and Managing RequirementsCyclone Requiremen

  20. Sound Search Engine Concept

    DEFF Research Database (Denmark)

    2006-01-01

    Sound search is provided by the major search engines, however, indexing is text based, not sound based. We will establish a dedicated sound search services with based on sound feature indexing. The current demo shows the concept of the sound search engine. The first engine will be realased June...

  1. Designing requirements engineering research

    NARCIS (Netherlands)

    Wieringa, Roelf J.; Heerkens, Johannes M.G.

    2007-01-01

    Engineering sciences study different topics than natural sciences, and utility is an essential factor in choosing engineering research problems. But despite these differences, research methods for the engineering sciences are no different than research methods for any other kind of science. At most

  2. Business Engineering Model

    OpenAIRE

    Österle, Hubert; Blessing, Dieter

    2000-01-01

    Business Engineering bedeutet systematische Entwicklung neuer Geschäftslösungen. Business Engineering zerlegt die Transformation von Unternehmen in beherrschbare Schritte, gibt Anleitung zur Bearbeitung dieser Schritte und verbindet diese in Vorgehensmodellen für Projekte. Der Aufsatz erklärt die Arbeitsweise des Business Engineering anhand eines durchgängigen Beispiels und beschreibt die Grundprinzipien dieser neuen Disziplin.

  3. Vascularization in tissue engineering

    NARCIS (Netherlands)

    Rouwkema, Jeroen; Rivron, Nicolas C.; Blitterswijk, van Clemens A.

    2008-01-01

    Tissue engineering has been an active field of research for several decades now. However, the amount of clinical applications in the field of tissue engineering is still limited. One of the current limitations of tissue engineering is its inability to provide sufficient blood supply in the initial p

  4. Matlab in electrical engineering

    OpenAIRE

    Stelian MARINESCU; Gabriel CHEREGI; Marilena STANCULESCU

    2009-01-01

    Electrical Engineering education addresses to high technologies needs from industry and business offering academic curricula which include topics such as: integrated circuits, digital signal processing, microwaves, optical engineering, bioelectronics, propagation and radiation, power electronics, control systems, communications, circuit theory, robotics, nondestructive testing. Matlab is a widely used tool in electrical engineering. It can be used to enhance and accelerate some processes, suc...

  5. Engineers and Bildung

    DEFF Research Database (Denmark)

    2006-01-01

    and Bildung. In this chapter, this relation in investigated. In the first part, I present three engineers and their careers. In the second part, the concept of Bildung is analyzed, and in the third part, it is the conceptual relation between Bildung, engineers, and engineering work that is of concern....

  6. Hybrid intelligent engineering systems

    CERN Document Server

    Jain, L C; Adelaide, Australia University of

    1997-01-01

    This book on hybrid intelligent engineering systems is unique, in the sense that it presents the integration of expert systems, neural networks, fuzzy systems, genetic algorithms, and chaos engineering. It shows that these new techniques enhance the capabilities of one another. A number of hybrid systems for solving engineering problems are presented.

  7. Sound Search Engine Concept

    DEFF Research Database (Denmark)

    2006-01-01

    Sound search is provided by the major search engines, however, indexing is text based, not sound based. We will establish a dedicated sound search services with based on sound feature indexing. The current demo shows the concept of the sound search engine. The first engine will be realased June...

  8. Geology and bedrock engineering

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1985-11-15

    This book deals with geology of Korea which includes summary, geology in central part and southern part in Korea and characteristic of geology structure, limestone like geology property of limestone, engineered property of limestone, and design and construction case in limestone area. It also introduces engineered property of the cenozoic, clay rock and shale, geologic and engineered property of phyllite and stratum.

  9. Kali Linux social engineering

    CERN Document Server

    Singh, Rahul

    2013-01-01

    This book is a practical, hands-on guide to learning and performing SET attacks with multiple examples.Kali Linux Social Engineering is for penetration testers who want to use BackTrack in order to test for social engineering vulnerabilities or for those who wish to master the art of social engineering attacks.

  10. Advances in Medical Engineering

    CERN Document Server

    Buzug, Thorsten M

    2007-01-01

    Presents research and development trends of physics, engineering, mathematics and computer sciences in biomedical engineering. This work uses contributions from industry, clinics, universities and research labs with foci on medical imaging, computer-assisted surgery, and others to give insight to engineering, clinical and mathematical studies.

  11. RL-10 Engine

    Science.gov (United States)

    1960-01-01

    RL-10 engine characteristics. The RL-10 engine was developed under the management of the Marshall Space Flight Center (MSFC) to power the Saturn I upper stage (S-IV stage). The six RL-10 engines, which used liquid hydrogen and liquid oxygen as propellants, were arranged in a circle on the aft end of the S-IV stage.

  12. Experimental study of tissue-engineered skill loaded with keratinocyte growth factor nanocapsules for skin defect%荷载角质细胞生长因子纳米微囊组织工程皮肤修复裸鼠皮肤缺损

    Institute of Scientific and Technical Information of China (English)

    杨斌; 丘日升; 洪清琦; 冀晨阳

    2009-01-01

    目的 研究荷载角质细胞生长因子(keratinocyte growth factor,KGF)纳米微囊的新型组织工程皮肤对裸鼠皮肤缺损的修复效果及特点.方法 采用超声乳化一溶剂挥发法及低温干燥法,制备KGF纳米微囊,并构建KGF-脱细胞真皮基质(acellular dermal matrix,ADM);分离培养和鉴定人表皮干细胞群和成纤维细胞;接种表皮干细胞群于KGF-ADM之上,观察其生长情况;将荷载KGF纳米微囊的组织工程皮肤移植于裸鼠皮肤缺损处,以无KGF纳米微囊的组织工程皮肤为空白组,以其自体皮肤移植作对照组.于术后2,6周时分别观察修复区组织学愈合及皮片挛缩情况,并应用抗人角蛋白10及β1-整合素免疫荧光检测修复区表皮和真皮层细胞来源、分化及生长情况.结果 表皮干细胞群在KGF-ADM表面生长良好,粘贴紧密,可见到多角形的终末表皮细胞及小圆形的表皮干细胞,活性良好,有连接成片的趋势,部分形成克隆团块.以荷载KGF纳米微囊组织工程皮肤修复裸鼠皮肤缺损,2、6周时修复效果均优于空白组及对照组,移植的组织工程皮肤边缘可与邻近皮肤完全融合,但存在一定的挛缩.镜下可见修复区组织工程皮肤表皮细胞分层良好,与ADM紧密结合,能产生正常角质层.6周时实验组修复区组织工程皮肤切片免疫荧光检测,基底层仍存有少量β1-整合素阳性的表皮干细胞或短暂扩充细胞.结论 所构建的荷载KGF纳米微囊组织工程皮肤修复裸鼠皮肤缺损的效果,优于无KGF纳米微囊的普通组织工程皮肤及裸鼠自体全厚皮片移植修复效果.%Objective To study the effect of tissue-engineered skin loaded with keratinocyte growth factor (KGF) nanocapsules for skin defect on athymic mice. Methods The acellular dermal matrix(ADM) loaded with KGF-ADM was constructed by means of phaceemulsification solvent evaporation and low temperature drying. The human epidermal stem cells and

  13. Mouth Growths

    Science.gov (United States)

    ... This Article Medical Dictionary Also of Interest (Quiz) Biology of the Mouth (Video) Root Canal Additional Content Medical News Mouth Growths By David F. Murchison, DDS, MMS, Clinical Professor, Department of Biological Sciences;Clinical Professor, The University ...

  14. Growth Problems

    Science.gov (United States)

    ... that can lead to significantly short stature is dwarfism . Dwarfism results from abnormal growth of the bones and cartilage in the body. In many forms of dwarfism the person has abnormal body proportions, such as ...

  15. Maintaining Growth

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    China's GDP grew 9.2 percent in 2011,a remarkable achievement outshining many other countries.However,the current condition of the national economy is less than appealing.The sequential quarterly GDP growth rates for 2011 stood at 9.7 percent,9.5 percent,9.1 percent and 8.9 percent,showing a trend of deceleration.A consensus has been made that stabilizing growth should be the primary goal for China's economic development.

  16. Continuing engineering education for software engineering professionals

    Energy Technology Data Exchange (ETDEWEB)

    Davis, P.I.

    1992-02-19

    Designers of software for safety-critical applications are impelled to supplement their education through continuing engineering studies in the areas of requirements analysis, hazard identification, risk analysis, fault tolerance, failure modes, and psychology. Today`s complex level of design is contributing to opportunities for catastrophic design errors in computer functions where failure of such functions is capable of causing injury and death. A syllabus of post-graduate, core studies within the curricula of five engineering specialties is suggested. Software Engineers are exhorted to undertake a professional, responsible role in safety-critical software design.

  17. Continuing engineering education for software engineering professionals

    Energy Technology Data Exchange (ETDEWEB)

    Davis, P.I.

    1992-02-19

    Designers of software for safety-critical applications are impelled to supplement their education through continuing engineering studies in the areas of requirements analysis, hazard identification, risk analysis, fault tolerance, failure modes, and psychology. Today's complex level of design is contributing to opportunities for catastrophic design errors in computer functions where failure of such functions is capable of causing injury and death. A syllabus of post-graduate, core studies within the curricula of five engineering specialties is suggested. Software Engineers are exhorted to undertake a professional, responsible role in safety-critical software design.

  18. Population growth and economic growth.

    Science.gov (United States)

    Narayana, D L

    1984-01-01

    This discussion of the issues relating to the problem posed by population explosion in the developing countries and economic growth in the contemporary world covers the following: predictions of economic and social trends; the Malthusian theory of population; the classical or stationary theory of population; the medical triage model; ecological disaster; the Global 2000 study; the limits to growth; critiques of the Limits to Growth model; nonrenewable resources; food and agriculture; population explosion and stabilization; space and ocean colonization; and the limits perspective. The Limits to Growth model, a general equilibrium anti-growth model, is the gloomiest economic model ever constructed. None of the doomsday models, the Malthusian theory, the classical stationary state, the neo-Malthusian medical triage model, the Global 2000 study, are so far reaching in their consequences. The course of events that followed the publication of the "Limits to Growth" in 1972 in the form of 2 oil shocks, food shock, pollution shock, and price shock seemed to bear out formally the gloomy predictions of the thesis with a remarkable speed. The 12 years of economic experience and the knowledge of resource trends postulate that even if the economic pressures visualized by the model are at work they are neither far reaching nor so drastic. Appropriate action can solve them. There are several limitations to the Limits to Growth model. The central theme of the model, which is overshoot and collapse, is unlikely to be the course of events. The model is too aggregative to be realistic. It exaggerates the ecological disaster arising out of the exponential growth of population and industry. The gross underestimation of renewable resources is a basic flaw of the model. The most critical weakness of the model is its gross underestimation of the historical trend of technological progress and the technological possiblities within industry and agriculture. The model does correctly emphasize

  19. The Isothermal Dendritic Growth Experiment

    Science.gov (United States)

    Glicksman, M. E.; Koss, M. B.; Malarik, D. C.

    1998-01-01

    The growth of dendrites is one of the commonly observed forms of solidification encountered when metals and alloys freeze under low thermal gradients, as occurs in most casting and welding processes. In engineering alloys, the details of the dendritic morphology directly relates to important material responses and properties. Of more generic interest, dendritic growth is also an archetypical problem in morphogenesis, where a complex pattern evolves from simple starting conditions. Thus, the physical understanding and mathematical description of how dendritic patterns emerge during the growth process are of interest to both scientists and engineers. The Isothermal Dendritic Growth Experiment (IDGE) is a basic science experiment designed to measure, for a fundamental test of theory, the kinetics and morphology of dendritic growth without complications induced by gravity-driven convection. The IDGE, a collaboration between Rensselaer Polytechnic Institute, in Troy NY, and NASA's Lewis Research Center (LeRC) was developed over a ten year period from a ground-based research program into a space flight experiment. Important to the success of this flight experiment was provision of in situ near-real-time teleoperations during the spaceflight experiment.

  20. Quantum mechanical Carnot engine

    CERN Document Server

    Bender, C M; Meister, B K

    2000-01-01

    A cyclic thermodynamic heat engine runs most efficiently if it is reversible. Carnot constructed such a reversible heat engine by combining adiabatic and isothermal processes for a system containing an ideal gas. Here, we present an example of a cyclic engine based on a single quantum-mechanical particle confined to a potential well. The efficiency of this engine is shown to equal the Carnot efficiency because quantum dynamics is reversible. The quantum heat engine has a cycle consisting of adiabatic and isothermal quantum processes that are close analogues of the corresponding classical processes.

  1. Handbook of Engineering Acoustics

    CERN Document Server

    Möser, Michael

    2013-01-01

    This book examines the physical background of engineering acoustics, focusing on empirically obtained engineering experience as well as on measurement techniques and engineering methods for prognostics. Its goal is not only to describe the state of art of engineering acoustics but also to give practical help to engineers in order to solve acoustic problems. It deals with the origin, the transmission and the methods of the abating different kinds of air-borne and structure-borne sounds caused by various mechanisms – from traffic to machinery and flow-induced sound. In addition the modern aspects of room and building acoustics, as well as psychoacoustics and active noise control, are covered.

  2. Modern engineering thermodynamics

    CERN Document Server

    Balmer, Robert T

    2010-01-01

    Designed for use in a standard two-semester engineering thermodynamics course sequence. The first half of the text contains material suitable for a basic Thermodynamics course taken by engineers from all majors. The second half of the text is suitable for an Applied Thermodynamics course in mechanical engineering programs. The text has numerous features that are unique among engineering textbooks, including historical vignettes, critical thinking boxes, and case studies. All are designed to bring real engineering applications into a subject that can be somewhat abstract and mathematica

  3. Programming Google App Engine

    CERN Document Server

    Sanderson, Dan

    2010-01-01

    As one of today's cloud computing services, Google App Engine does more than provide access to a large system of servers. It also offers you a simple model for building applications that scale automatically to accommodate millions of users. With Programming Google App Engine, you'll get expert practical guidance that will help you make the best use of this powerful platform. Google engineer Dan Sanderson shows you how to design your applications for scalability, including ways to perform common development tasks using App Engine's APIs and scalable services. You'll learn about App Engine's a

  4. Tumor Engineering: The Other Face of Tissue Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Ghajar, Cyrus M; Bissell, Mina J

    2010-03-09

    cancer, the training grounds have largely consisted of small rodents, despite marked differences between human and mouse physiology, or plastic dishes, even though just like our tissues and organs most tumors exist within three-dimensional proteinacious milieus. One could argue that this is comparable to training for a desert war in the arctic. In this special issue of tissue engineering, Fischbach-Teschl and colleagues build a strong case for engineering complex cultures analogous to normal organs to tractably model aspects of the human tumor microenvironment that simply cannot be reproduced with traditional two-dimensional cell culture techniques and that cannot be studied in a controlled fashion in vivo. This idea has gained considerable traction of late as concepts presented and convincingly shown years ago have only now begun to be appreciated. Perhaps, then, it is time to organize those who wish to build complex tumor models to study cancer biology under a common umbrella. Accordingly, we propose that tumor engineering be defined as the construction of complex culture models that recapitulate aspects of the in vivo tumor microenvironment to study the dynamics of tumor development, progression, and therapy on multiple scales. Inherent in this definition is the collaboration that must occur between physical and life scientists to guide the design of patterning techniques, materials, and imaging modalities for the study of cancer from the subcellular to tissue level in physiologically relevant contexts. To date, the most successful tissue engineering approaches have employed methods that recapitulate the composition, architecture, and/or chemical presentation of native tissue. For instance, induction of blood vessel growth for therapeutic purposes has been achieved with sequential release of vascular endothelial growth factor (VEGF) and platelet derived growth factor to induce and stabilize blood vessels. This approach imitates that which occurs during physiological

  5. Search Engine Optimization through Spanning Forest Generation Algorithm

    Directory of Open Access Journals (Sweden)

    SATYA PAVAN KUMAR SOMAYAJULA

    2011-09-01

    Full Text Available Search engine technology has had to scale dramatically to keep up with the growth of the web. With the tremendous growth of information available to end users through the Web, search engines come to play ever a more critical role. Determining the user intent of Web searches is a difficult problem due to the sparse data available concerning the searcher. We qualitatively analyze samples of queries from seven transaction logs from three different Web search engines containing more than five million queries. The following are our research objectives: Isolate characteristics of informational, navigational, and transactional for Web searching queries by identifying characteristics of each query type that will lead toreal world classification. Validate the taxonomy by automatically classifying a large set of queries from a Web search engine. This paper we deal with now is semantic web search engines is the layeredarchitecture and we use this with relation based page rank algorithm.

  6. The spatial dynamics of ecosystem engineers.

    Science.gov (United States)

    Franco, Caroline; Fontanari, José F

    2017-10-01

    The changes on abiotic features of ecosystems have rarely been taken into account by population dynamics models, which typically focus on trophic and competitive interactions between species. However, understanding the population dynamics of organisms that must modify their habitats in order to survive, the so-called ecosystem engineers, requires the explicit incorporation of abiotic interactions in the models. Here we study a model of ecosystem engineers that is discrete both in space and time, and where the engineers and their habitats are arranged in patches fixed to the sites of regular lattices. The growth of the engineer population is modeled by Ricker equation with a density-dependent carrying capacity that is given by the number of modified habitats. A diffusive dispersal stage ensures that a fraction of the engineers move from their birth patches to neighboring patches. We find that dispersal influences the metapopulation dynamics only in the case that the local or single-patch dynamics exhibit chaotic behavior. In that case, it can suppress the chaotic behavior and avoid extinctions in the regime of large intrinsic growth rate of the population. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Stirling engine application study

    Science.gov (United States)

    Teagan, W. P.; Cunningham, D.

    1983-01-01

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

  8. Engineered phages for electronics.

    Science.gov (United States)

    Cui, Yue

    2016-11-15

    Phages are traditionally widely studied in biology and chemistry. In recent years, engineered phages have attracted significant attentions for functionalization or construction of electronic devices, due to their specific binding, catalytic, nucleating or electronic properties. To apply the engineered phages in electronics, these are a number of interesting questions: how to engineer phages for electronics? How are the engineered phages characterized? How to assemble materials with engineered phages? How are the engineered phages micro or nanopatterned? What are the strategies to construct electronics devices with engineered phages? This review will highlight the early attempts to address these questions and explore the fundamental and practical aspects of engineered phages in electronics, including the approaches for selection or expression of specific peptides on phage coat proteins, characterization of engineered phages in electronics, assembly of electronic materials, patterning of engineered phages, and construction of electronic devices. It provides the methodologies and opens up ex-cit-ing op-por-tu-ni-ties for the development of a variety of new electronic materials and devices based on engineered phages for future applications.

  9. Systems Engineering Analysis

    Directory of Open Access Journals (Sweden)

    Alexei Serna M.

    2013-07-01

    Full Text Available The challenges proposed by the development of the new computer systems demand new guidance related to engineer´s education, because they will solve these problems. In the XXI century, system engineers must be able to integrate a number of topics and knowledge disciplines that complement that traditionally has been known as Computer Systems Engineering. We have enough software development engineers, today we need professional engineers for software integration, leaders and system architects that make the most of the technological development for the benefit of society, leaders that integrate sciences to the solutions they build and propose. In this article the current situation of Computer Systems Engineering is analyzed and is presented a theory proposing the need for modifying the approach Universities have given to these careers, to achieve the education of leader engineers according to the needs of this century.

  10. Diesel Engine Tribology

    DEFF Research Database (Denmark)

    Christiansen, Christian Kim

    Recent years have seen an increase in the wear rate of engine bearings, subsequently followed by bearing failure, for the large two-stroke diesel engines used for ship propulsion. Here, the engine bearings include main, big end and crosshead bearings, with the bearing type used being the journal...... bearing, belonging to the class of ‘hydrodynamic bearings’. This implies that the load carrying capacity is generated by a relative movement of the involved components, i.e. avelocity-driven operation. For the engine application, the velocity stems from the engine RPM. However, to comply with the latest...... emission requirements as well as attempting to minimise fuel expenses, the engine speed has been lowered together with an increase in the engine mean pressure which in terms lead to larger bearing loads. With worsened operating conditions from two sides, the encountered problems are understandable...

  11. Culture in Engineering Education

    DEFF Research Database (Denmark)

    Hoffmann, Birgitte; Jørgensen, Ulrik; Christensen, Hans Peter

    2011-01-01

    As engineers today often work in intercultural projects and contexts, intercultural competences must be part of the learning objectives in engineering educations. Cultural aspects of engineering education should not just be treated as a question of appropriate communication and teaching: cultural...... to cultural aspects in engineering education. Hence the key-question of this paper is how CDIO support the development of intercultural competences in engineering education. The paper explores the implementation of CDIO in an intercultural arctic engineering programme in Greenland that since 2001 has been...... enrolling students with special focus on developing intercultural competences. The discussion draws on the socio-technical approaches to technology and professional engineering practises [5,6]. We conclude that intercultural teaching is not just a matter of teaching in spite of cultural differences...

  12. Hot Air Engines

    Directory of Open Access Journals (Sweden)

    P. Stouffs

    2011-01-01

    Full Text Available Invented in 1816, the hot-air engines have known significant commercial success in the nineteenth century, before falling into disuse. Nowadays they enjoy a renewed interest for some specific applications. The "hot-air engines" family is made up of two groups: Stirling engines and Ericsson engines. The operating principle of Stirling and Ericsson engines, their troubled history, their advantages and their niche applications are briefly presented, especially in the field of micro-combined heat and power, solar energy conversion and biomass energy conversion. The design of an open cycle Ericsson engine for solar application is proposed. A first prototype of the hot part of the engine has been built and tested. Experimental results are presented.

  13. Modeling Tissue Growth Within Nonwoven Scaffolds Pores

    Science.gov (United States)

    Church, Jeffrey S.; Alexander, David L.J.; Russell, Stephen J.; Ingham, Eileen; Ramshaw, John A.M.; Werkmeister, Jerome A.

    2011-01-01

    In this study we present a novel approach for predicting tissue growth within the pores of fibrous tissue engineering scaffolds. Thin nonwoven polyethylene terephthalate scaffolds were prepared to characterize tissue growth within scaffold pores, by mouse NR6 fibroblast cells. On the basis of measurements of tissue lengths at fiber crossovers and along fiber segments, mathematical models were determined during the proliferative phase of cell growth. Tissue growth at fiber crossovers decreased with increasing interfiber angle, with exponential relationships determined on day 6 and 10 of culture. Analysis of tissue growth along fiber segments determined two growth profiles, one with enhanced growth as a result of increased tissue lengths near the fiber crossover, achieved in the latter stage of culture. Derived mathematical models were used in the development of a software program to visualize predicted tissue growth within a pore. This study identifies key pore parameters that contribute toward tissue growth, and suggests models for predicting this growth, based on fibroblast cells. Such models may be used in aiding scaffold design, for optimum pore infiltration during the tissue engineering process. PMID:20687775

  14. Engineering Science, Skills, and Bildung

    DEFF Research Database (Denmark)

    Christensen, Jens

    The background for the book is a quest for a thorough analysis of engineering, engineering science, and engineering education. Focusing on the concepts of engineering science, skills, and Bildung, the book investigates the real challenges that are confronting engineering today, and discusses how...... to respond to these. Thereby, the book offers a complex and nuanced basis for debates on the actual status and the future directions of engineering science, engineering education, and the everyday practice of engineers....

  15. Da "Search engines" a "Shop engines"

    OpenAIRE

    Lupi, Mauro

    2001-01-01

    The change occuring related to “search engines” is going towards e-commerce, transforming all the main search engines into information and commercial suggestion conveying means, basing their businnes on this activity. In a next future we will find two main series of search engines: from one side, the portals that will offer a general orientation guide being convoying means for services and to-buy products; from the other side, vertical portals able to offer information and products on specifi...

  16. Mechanical Engineering Department technical review

    Energy Technology Data Exchange (ETDEWEB)

    Carr, R.B.; Abrahamson, L.; Denney, R.M.; Dubois, B.E (eds.)

    1982-01-01

    Technical achievements and publication abstracts related to research in the following Divisions of Lawrence Livermore Laboratory are reported in this biannual review: Nuclear Fuel Engineering; Nuclear Explosives Engineering; Weapons Engineering; Energy Systems Engineering; Engineering Sciences; Magnetic Fusion Engineering; and Material Fabrication. (LCL)

  17. Tissue engineering skeletal muscle for orthopaedic applications

    Science.gov (United States)

    Payumo, Francis C.; Kim, Hyun D.; Sherling, Michael A.; Smith, Lee P.; Powell, Courtney; Wang, Xiao; Keeping, Hugh S.; Valentini, Robert F.; Vandenburgh, Herman H.

    2002-01-01

    With current technology, tissue-engineered skeletal muscle analogues (bioartificial muscles) generate too little active force to be clinically useful in orthopaedic applications. They have been engineered genetically with numerous transgenes (growth hormone, insulinlike growth factor-1, erythropoietin, vascular endothelial growth factor), and have been shown to deliver these therapeutic proteins either locally or systemically for months in vivo. Bone morphogenetic proteins belonging to the transforming growth factor-beta superfamily are osteoinductive molecules that drive the differentiation pathway of mesenchymal cells toward the chondroblastic or osteoblastic lineage, and stimulate bone formation in vivo. To determine whether skeletal muscle cells endogenously expressing bone morphogenetic proteins might serve as a vehicle for systemic bone morphogenetic protein delivery in vivo, proliferating skeletal myoblasts (C2C12) were transduced with a replication defective retrovirus containing the gene for recombinant human bone morphogenetic protein-6 (C2BMP-6). The C2BMP-6 cells constitutively expressed recombinant human bone morphogenetic protein-6 and synthesized bioactive recombinant human bone morphogenetic protein-6, based on increased alkaline phosphatase activity in coincubated mesenchymal cells. C2BMP-6 cells did not secrete soluble, bioactive recombinant human bone morphogenetic protein-6, but retained the bioactivity in the cell layer. Therefore, genetically-engineered skeletal muscle cells might serve as a platform for long-term delivery of osteoinductive bone morphogenetic proteins locally.

  18. Diversity in the utilization of glucose and lactate in synthetic mammalian myotubes generated by engineered configurations of MyoD and E12 in otherwise non-differentiation growth conditions.

    Science.gov (United States)

    Grubišić, Vladimir; Parpura, Vladimir

    2015-03-01

    We previously used the expression of various combinations and configurations of MyoD and E12, two basic helix-loop-helix transcription factors (TF), to produce populations of myotubes assuming distinct morphology, myofibrillar development and Ca2+ dynamics, from mammalian C2C12 myoblasts in non-differentiation growth conditions. Here, we assessed the synthetically generated myotubes in terms of energetics, otherwise necessary to sustain their mechanical output as bio-actuators. We found that the myotubes exhibit changed expression of key regulators for the uptake and utilization of two major cellular fuels, glucose and lactate. Furthermore, while lactate transport was uniformly slowed in all the populations of myotubes, glucose uptake and utilization were modified by particular TF configuration. Our approach allows the production of a class of biomaterials with predetermined energetics that could be applied in biorobotics, where fuel of choice could be used, and also in reparative medicine where, for example, particular population of myotubes could be additionally employed as glucose sinks to mitigate effects of secondary metabolic syndrome.

  19. Engineered Solution-Liquid-Solid Growth of a "Treelike" 1D/1D TiO2 Nanotube-CdSe Nanowire Heterostructure: Photoelectrochemical Conversion of Broad Spectrum of Solar Energy.

    Science.gov (United States)

    Mukherjee, Bratindranath; Sarker, Swagotom; Crone, Eric; Pathak, Pawan; Subramanian, Vaidyanathan R

    2016-12-07

    This work presents a hitherto unreported approach to assemble a 1D oxide-1D chalcogenide heterostructured photoactive film. As a representative system, bismuth (Bi) catalyzed 1D CdSe nanowires are directly grown on anodized 1D TiO2 nanotube (T_NT). A combination of the reductive successive-ionic-layer-adsorption-reaction (R-SILAR) and the solution-liquid-solid (S-L-S) approach is implemented to fabricate this heterostructured assembly, reported in this 1D/1D form for the first time. XRD, SEM, HRTEM, and elemental mapping are performed to systematically characterize the deposition of bismuth on T_NT and the growth of CdSe nanowires leading to the evolution of the 1D/1D heterostructure. The resulting "treelike" photoactive architecture demonstrates UV-visible light-driven electron-hole pair generation. The photoelectrochemical results highlight: (i) the formation of a stable n-n heterojunction between TiO2 nanotube and CdSe nanowire, (ii) an excellent correlation between the absorbance vis-à-vis light conversion efficiency (IPCE), and (iii) a photocurrent density of 3.84 mA/cm(2). This proof-of-concept features the viability of the approach for designing such complex 1D/1D oxide-chalcogenide heterostructures that can be of interest to photovoltaics, photocatalysis, environmental remediation, and sensing.

  20. Bioactive glass in tissue engineering

    Science.gov (United States)

    Rahaman, Mohamed N.; Day, Delbert E.; Bal, B. Sonny; Fu, Qiang; Jung, Steven B.; Bonewald, Lynda F.; Tomsia, Antoni P.

    2011-01-01

    This review focuses on recent advances in the development and use of bioactive glass for tissue engineering applications. Despite its inherent brittleness, bioactive glass has several appealing characteristics as a scaffold material for bone tissue engineering. New bioactive glasses based on borate and borosilicate compositions have shown the ability to enhance new bone formation when compared to silicate bioactive glass. Borate-based bioactive glasses also have controllable degradation rates, so the degradation of the bioactive glass implant can be more closely matched to the rate of new bone formation. Bioactive glasses can be doped with trace quantities of elements such as Cu, Zn and Sr, which are known to be beneficial for healthy bone growth. In addition to the new bioactive glasses, recent advances in biomaterials processing have resulted in the creation of scaffold architectures with a range of mechanical properties suitable for the substitution of loaded as well as non-loaded bone. While bioactive glass has been extensively investigated for bone repair, there has been relatively little research on the application of bioactive glass to the repair of soft tissues. However, recent work has shown the ability of bioactive glass to promote angiogenesis, which is critical to numerous applications in tissue regeneration, such as neovascularization for bone regeneration and the healing of soft tissue wounds. Bioactive glass has also been shown to enhance neocartilage formation during in vitro culture of chondrocyte-seeded hydrogels, and to serve as a subchondral substrate for tissue-engineered osteochondral constructs. Methods used to manipulate the structure and performance of bioactive glass in these tissue engineering applications are analyzed. PMID:21421084

  1. Microfluidics and microbial engineering.

    Science.gov (United States)

    Kou, Songzi; Cheng, Danhui; Sun, Fei; Hsing, I-Ming

    2016-02-01

    The combination of microbial engineering and microfluidics is synergistic in nature. For example, microfluidics is benefiting from the outcome of microbial engineering and many reported point-of-care microfluidic devices employ engineered microbes as functional parts for the microsystems. In addition, microbial engineering is facilitated by various microfluidic techniques, due to their inherent strength in high-throughput screening and miniaturization. In this review article, we firstly examine the applications of engineered microbes for toxicity detection, biosensing, and motion generation in microfluidic platforms. Secondly, we look into how microfluidic technologies facilitate the upstream and downstream processes of microbial engineering, including DNA recombination, transformation, target microbe selection, mutant characterization, and microbial function analysis. Thirdly, we highlight an emerging concept in microbial engineering, namely, microbial consortium engineering, where the behavior of a multicultural microbial community rather than that of a single cell/species is delineated. Integrating the disciplines of microfluidics and microbial engineering opens up many new opportunities, for example in diagnostics, engineering of microbial motors, development of portable devices for genetics, high throughput characterization of genetic mutants, isolation and identification of rare/unculturable microbial species, single-cell analysis with high spatio-temporal resolution, and exploration of natural microbial communities.

  2. Engineering plants for spaceflight environments

    Science.gov (United States)

    Bugbee, B.

    1999-01-01

    The conversion efficiency of radiation into biomass and yield has steadily increased for centuries because of continued improvement in both plant genetics and environmental control. Considerable effort has gone into improving the environment for plant growth in space, but work has only begun to engineer plants for spaceflight. Genetic manipulation offers tremendous potential to improve our ability to study gravitational effects. Genetic manipulation will also be necessary to build an efficient regenerative life support system. We cannot fully characterize plant response to the spaceflight environment without understanding and manipulating their genetic composition. Identification and selection of the existing germplasm is the first step. There are thousands of cultivars of each of our major crop plants, each specifically adapted to a unique environment on our planet. Thousands of additional lines are held in national germplasm collections to maintain genetic diversity. Spaceflight imposes the need to tap this diversity. Existing lines need to be evaluated in the environment that is characteristic of closed-system spaceflight conditions. Many of the plant growth challenges we confront in space can be better solved through genetic change than by hardware engineering. Ten thousand years of plant breeding has demonstrated the value of matching genetics with the environment. For example, providing continuous light can increase plant growth in space, but this often induces calcium deficiencies because Ca is not supplied by guttation during a dark period. This deficiency cannot be eliminated through increased root-zone and foliar Ca applications. It can be solved, in wheat, through genetic selection of lines that do not have the deficiency. Subsequent comparison of lines with and without the Ca deficiency has also helped us understand the nature of the problem.

  3. New generation of the multimedia search engines

    Science.gov (United States)

    Mijes Cruz, Mario Humberto; Soto Aldaco, Andrea; Maldonado Cano, Luis Alejandro; López Rodríguez, Mario; Rodríguez Vázqueza, Manuel Antonio; Amaya Reyes, Laura Mariel; Cano Martínez, Elizabeth; Pérez Rosas, Osvaldo Gerardo; Rodríguez Espejo, Luis; Flores Secundino, Jesús Abimelek; Rivera Martínez, José Luis; García Vázquez, Mireya Saraí; Zamudio Fuentes, Luis Miguel; Sánchez Valenzuela, Juan Carlos; Montoya Obeso, Abraham; Ramírez Acosta, Alejandro Álvaro

    2016-09-01

    Current search engines are based upon search methods that involve the combination of words (text-based search); which has been efficient until now. However, the Internet's growing demand indicates that there's more diversity on it with each passing day. Text-based searches are becoming limited, as most of the information on the Internet can be found in different types of content denominated multimedia content (images, audio files, video files). Indeed, what needs to be improved in current search engines is: search content, and precision; as well as an accurate display of expected search results by the user. Any search can be more precise if it uses more text parameters, but it doesn't help improve the content or speed of the search itself. One solution is to improve them through the characterization of the content for the search in multimedia files. In this article, an analysis of the new generation multimedia search engines is presented, focusing the needs according to new technologies. Multimedia content has become a central part of the flow of information in our daily life. This reflects the necessity of having multimedia search engines, as well as knowing the real tasks that it must comply. Through this analysis, it is shown that there are not many search engines that can perform content searches. The area of research of multimedia search engines of new generation is a multidisciplinary area that's in constant growth, generating tools that satisfy the different needs of new generation systems.

  4. Bone Tissue Engineering: Recent Advances and Challenges

    Science.gov (United States)

    Amini, Ami R.; Laurencin, Cato T.; Nukavarapu, Syam P.

    2013-01-01

    The worldwide incidence of bone disorders and conditions has trended steeply upward and is expected to double by 2020, especially in populations where aging is coupled with increased obesity and poor physical activity. Engineered bone tissue has been viewed as a potential alternative to the conventional use of bone grafts, due to their limitless supply and no disease transmission. However, bone tissue engineering practices have not proceeded to clinical practice due to several limitations or challenges. Bone tissue engineering aims to induce new functional bone regeneration via the synergistic combination of biomaterials, cells, and factor therapy. In this review, we discuss the fundamentals of bone tissue engineering, highlighting the current state of this field. Further, we review the recent advances of biomaterial and cell-based research, as well as approaches used to enhance bone regeneration. Specifically, we discuss widely investigated biomaterial scaffolds, micro- and nano-structural properties of these scaffolds, and the incorporation of biomimetic properties and/or growth factors. In addition, we examine various cellular approaches, including the use of mesenchymal stem cells (MSCs), embryonic stem cells (ESCs), adult stem cells, induced pluripotent stem cells (iPSCs), and platelet-rich plasma (PRP), and their clinical application strengths and limitations. We conclude by overviewing the challenges that face the bone tissue engineering field, such as the lack of sufficient vascularization at the defect site, and the research aimed at functional bone tissue engineering. These challenges will drive future research in the field. PMID:23339648

  5. A global assessment of stem cell engineering.

    Science.gov (United States)

    Loring, Jeanne F; McDevitt, Todd C; Palecek, Sean P; Schaffer, David V; Zandstra, Peter W; Nerem, Robert M

    2014-10-01

    Over the last 2 years a global assessment of stem cell engineering (SCE) was conducted with the sponsorship of the National Science Foundation, the National Cancer Institute at the National Institutes of Health, and the National Institute of Standards and Technology. The purpose was to gather information on the worldwide status and trends in SCE, that is, the involvement of engineers and engineering approaches in the stem cell field, both in basic research and in the translation of research into clinical applications and commercial products. The study was facilitated and managed by the World Technology Evaluation Center. The process involved site visits in both Asia and Europe, and it also included several different workshops. From this assessment, the panel concluded that there needs to be an increased role for engineers and the engineering approach. This will provide a foundation for the generation of new markets and future economic growth. To do this will require an increased investment in engineering, applied research, and commercialization as it relates to stem cell research and technology. It also will require programs that support interdisciplinary teams, new innovative mechanisms for academic-industry partnerships, and unique translational models. In addition, the global community would benefit from forming strategic partnerships between countries that can leverage existing and emerging strengths in different institutions. To implement such partnerships will require multinational grant programs with appropriate review mechanisms.

  6. Genetic Engineering Strategies for Enhanced Biodiesel Production.

    Science.gov (United States)

    Hegde, Krishnamoorthy; Chandra, Niharika; Sarma, Saurabh Jyoti; Brar, Satinder Kaur; Veeranki, Venkata Dasu

    2015-07-01

    The focus on biodiesel research has shown a tremendous growth over the last few years. Several microbial and plant sources are being explored for the sustainable biodiesel production to replace the petroleum diesel. Conventional methods of biodiesel production have several limitations related to yield and quality, which led to development of new engineering strategies to improve the biodiesel production in plants, and microorganisms. Substantial progress in utilizing algae, yeast, and Escherichia coli for the renewable production of biodiesel feedstock via genetic engineering of fatty acid metabolic pathways has been reported in the past few years. However, in most of the cases, the successful commercialization of such engineering strategies for sustainable biodiesel production is yet to be seen. This paper systematically presents the drawbacks in the conventional methods for biodiesel production and an exhaustive review on the present status of research in genetic engineering strategies for production of biodiesel in plants, and microorganisms. Further, we summarize the technical challenges need to be tackled to make genetic engineering technology economically sustainable. Finally, the need and prospects of genetic engineering technology for the sustainable biodiesel production and the recommendations for the future research are discussed.

  7. A Global Assessment of Stem Cell Engineering

    Science.gov (United States)

    Loring, Jeanne F.; McDevitt, Todd C.; Palecek, Sean P.; Schaffer, David V.; Zandstra, Peter W.

    2014-01-01

    Over the last 2 years a global assessment of stem cell engineering (SCE) was conducted with the sponsorship of the National Science Foundation, the National Cancer Institute at the National Institutes of Health, and the National Institute of Standards and Technology. The purpose was to gather information on the worldwide status and trends in SCE, that is, the involvement of engineers and engineering approaches in the stem cell field, both in basic research and in the translation of research into clinical applications and commercial products. The study was facilitated and managed by the World Technology Evaluation Center. The process involved site visits in both Asia and Europe, and it also included several different workshops. From this assessment, the panel concluded that there needs to be an increased role for engineers and the engineering approach. This will provide a foundation for the generation of new markets and future economic growth. To do this will require an increased investment in engineering, applied research, and commercialization as it relates to stem cell research and technology. It also will require programs that support interdisciplinary teams, new innovative mechanisms for academic–industry partnerships, and unique translational models. In addition, the global community would benefit from forming strategic partnerships between countries that can leverage existing and emerging strengths in different institutions. To implement such partnerships will require multinational grant programs with appropriate review mechanisms. PMID:24428577

  8. Investigation and analysis of growth condition of big trees transplanting in garden engineering%园林工程移植大树的生长状况调查与分析

    Institute of Scientific and Technical Information of China (English)

    刘立民; 朱艳春; 张文军

    2013-01-01

    Based on different growth conditions of big trees transplanting in Changchun , the re-sults indicated that average DBH of the big trees surveyed in greenbelt was 6.5 ~26.0 cm, both average survival rate and tendency survival rate were 60 .8%, and death rate and tendency death rate were 39.2%.Pinus sylvetris var.mongolica transplanted in the spring of 2013 , av-erage DBH of big trees was 11.8 cm, the death rate was 48.6%, and that average DBH of trees were 7.5 cm, theier death rate was only 3.5%.Smalle dimension of the transplant was easy to survive .%长春市不同绿地移植大树的生长状况调查结果表明:调查绿地移植的大树(平均胸径16.5~26.0 cm)平均成活与趋向成活率只有60.8%,死亡和趋向死亡率却高达39.2%。2013年春季栽植的樟子松大树,平均胸径为11.8 cm的大树,死亡率为48.6%,而平均胸径为7.5 cm的树木,死亡率只有3.5%。移植体量小的植株容易成活。

  9. Staged combustion with piston engine and turbine engine supercharger

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Larry E [Los Gatos, CA; Anderson, Brian L [Lodi, CA; O' Brien, Kevin C [San Ramon, CA

    2011-11-01

    A combustion engine method and system provides increased fuel efficiency and reduces polluting exhaust emissions by burning fuel in a two-stage combustion system. Fuel is combusted in a piston engine in a first stage producing piston engine exhaust gases. Fuel contained in the piston engine exhaust gases is combusted in a second stage turbine engine. Turbine engine exhaust gases are used to supercharge the piston engine.

  10. Embedded engineering education

    CERN Document Server

    Kaštelan, Ivan; Temerinac, Miodrag; Barak, Moshe; Sruk, Vlado

    2016-01-01

    This book focuses on the outcome of the European research project “FP7-ICT-2011-8 / 317882: Embedded Engineering Learning Platform” E2LP. Additionally, some experiences and researches outside this project have been included. This book provides information about the achieved results of the E2LP project as well as some broader views about the embedded engineering education. It captures project results and applications, methodologies, and evaluations. It leads to the history of computer architectures, brings a touch of the future in education tools and provides a valuable resource for anyone interested in embedded engineering education concepts, experiences and material. The book contents 12 original contributions and will open a broader discussion about the necessary knowledge and appropriate learning methods for the new profile of embedded engineers. As a result, the proposed Embedded Computer Engineering Learning Platform will help to educate a sufficient number of future engineers in Europe, capable of d...

  11. Practical electrical engineering

    CERN Document Server

    N Makarov, Sergey; Bitar, Stephen J

    2016-01-01

    This textbook provides comprehensive, in-depth coverage of the fundamental concepts of electrical and computer engineering. It is written from an engineering perspective, with special emphasis on circuit functionality and applications. Reliance on higher-level mathematics and physics, or theoretical proofs has been intentionally limited in order to prioritize the practical aspects of electrical engineering. This text is therefore suitable for a number of introductory circuit courses for other majors such as robotics, mechanical, biomedical, aerospace, civil, architecture, petroleum, and industrial engineering. The authors’ primary goal is to teach the aspiring engineering student all fundamental tools needed to understand, analyze and design a wide range of practical circuits and systems. Their secondary goal is to provide a comprehensive reference, for both major and non-major students as well as practicing engineers. Provides a self-contained, fundamental textbook on electric circuits and basic electronic...

  12. Teaching Professional Engineering Skills

    DEFF Research Database (Denmark)

    Andersson, Niclas; Andersson, Pernille Hammar

    2010-01-01

    Engineering education aims at providing students with sufficient disciplinary knowledge of science and engineering principles in order for them to become successful engineers. However, to fulfil their roles as professional engineers, students also need to develop personal and interpersonal skills......, as well as professional skills, in order to implement and apply their theoretical and technical knowledge in a real context. CDIO constitutes a comprehensive approach to engineering education in which these additional skills represent fundamental principles besides the predominant technical knowledge....... The implementation of professional skills as well as personal and interpersonal skills in engineering teaching must be done, however, without reducing the existing curriculum of technical disciplines and still allow for the continuous acquisition of new technical knowledge. The general purpose of this study...

  13. Nanotechnology for chemical engineers

    CERN Document Server

    Salaheldeen Elnashaie, Said; Hashemipour Rafsanjani, Hassan

    2015-01-01

    The book describes the basic principles of transforming nano-technology into nano-engineering with a particular focus on chemical engineering fundamentals. This book provides vital information about differences between descriptive technology and quantitative engineering for students as well as working professionals in various fields of nanotechnology. Besides chemical engineering principles, the fundamentals of nanotechnology are also covered along with detailed explanation of several specific nanoscale processes from chemical engineering point of view. This information is presented in form of practical examples and case studies that help the engineers and researchers to integrate the processes which can meet the commercial production. It is worth mentioning here that, the main challenge in nanostructure and nanodevices production is nowadays related to the economic point of view. The uniqueness of this book is a balance between important insights into the synthetic methods of nano-structures and nanomaterial...

  14. Performance of Stirling Engines

    Science.gov (United States)

    Iwamoto, Shoichi; Hirata, Koichi; Toda, Fujio

    We have developed five kinds of high- and low-temperature differential Stirling engines and their engine performance was investigated experimentally. In order to determine the parameters that affect engine performance, experimental results were discussed and compared with results calculated using analytical methods. We show an arranging method for the experimental results, and consider the performance of general Stirling engines. After using the arranging method with nondimensional numbers obtained by a dimensional analysis, a prediction method, which is used at the early design stage, is formulated. One of the nondimensional numbers in this prediction method is calculated based on engine specifications, including the properties of the working gas. The prediction method can predict engine speed, output power, the effect of working gas and operating conditions.

  15. Engineering and design skills

    DEFF Research Database (Denmark)

    Schrøder, Anne Lise

    2006-01-01

    In various branches of society there is focus on the need for design skills and innovation potential as a means of communicating and handling constant change. In this context, the traditional idea of the engineer as a poly-technician inventing solutions by understanding the laws of nature...... concept of diagrammatic reasoning to some extent incarnates the very method of engineering and design. On this background, it is argued how the work field and techniques of the engineer and the engineering scientist could be characterized in a broader creative context of learning and communication....... This leads to considering the fundamental skills of the engineering practice as basic abilities to see the structures and dynamics of the world, to model it, and to create new solutions concerning practical as well as theoretical matters. Finally, it is assumed that the essence of engineering “bildung...

  16. Tissue Engineering Organs for Space Biology Research

    Science.gov (United States)

    Vandenburgh, H. H.; Shansky, J.; DelTatto, M.; Lee, P.; Meir, J.

    1999-01-01

    Long-term manned space flight requires a better understanding of skeletal muscle atrophy resulting from microgravity. Atrophy most likely results from changes at both the systemic level (e.g. decreased circulating growth hormone, increased circulating glucocorticoids) and locally (e.g. decreased myofiber resting tension). Differentiated skeletal myofibers in tissue culture have provided a model system over the last decade for gaining a better understanding of the interactions of exogenous growth factors, endogenous growth factors, and muscle fiber tension in regulating protein turnover rates and muscle cell growth. Tissue engineering these cells into three dimensional bioartificial muscle (BAM) constructs has allowed us to extend their use to Space flight studies for the potential future development of countermeasures.

  17. Superradiant Quantum Heat Engine

    OpenAIRE

    Ali Ü. C. Hardal; Müstecaplıoğlu, Özgür E.

    2015-01-01

    Scientific Reports | 5:12953 | DOI: 10.1038/srep12953 1 www.nature.com/scientificreports Superradiant Quantum Heat Engine Ali Ü. C. Hardal & Özgür E. Müstecaplıoğlu Quantum physics revolutionized classical disciplines of mechanics, statistical physics, and electrodynamics. One branch of scientific knowledge however seems untouched: thermodynamics. Major motivation behind thermodynamics is to develop eficient heat engines. Technology has a trend to miniaturize engines, ...

  18. Standing detonation wave engine

    KAUST Repository

    Kasimov, Aslan

    2015-10-08

    A detonation engine can detonate a mixture of fuel and oxidizer within a cylindrical detonation region to produce work. The detonation engine can have a first and a second inlet having ends fluidly connected from tanks to the detonation engine. The first and second inlets can be aligned along a common axis. The inlets can be connected to nozzles and a separator can be positioned between the nozzles and along the common axis.

  19. Software engineer's pocket book

    CERN Document Server

    Tooley, Michael

    2013-01-01

    Software Engineer's Pocket Book provides a concise discussion on various aspects of software engineering. The book is comprised of six chapters that tackle various areas of concerns in software engineering. Chapter 1 discusses software development, and Chapter 2 covers programming languages. Chapter 3 deals with operating systems. The book also tackles discrete mathematics and numerical computation. Data structures and algorithms are also explained. The text will be of great use to individuals involved in the specification, design, development, implementation, testing, maintenance, and qualit

  20. Electrical engineer's reference book

    CERN Document Server

    Laughton, M A

    1985-01-01

    Electrical Engineer's Reference Book, Fourteenth Edition focuses on electrical engineering. The book first discusses units, mathematics, and physical quantities, including the international unit system, physical properties, and electricity. The text also looks at network and control systems analysis. The book examines materials used in electrical engineering. Topics include conducting materials, superconductors, silicon, insulating materials, electrical steels, and soft irons and relay steels. The text underscores electrical metrology and instrumentation, steam-generating plants, turbines

  1. Shift for engineering horizons

    OpenAIRE

    Ciampi, M. M.; Brito, C. da R.; Vasconcelos, Rosa; Amaral, Luís; Barros, V. F. A.

    2016-01-01

    Science, Engineering and Technology cross nearly every facet of modern life and, as problem solvers, engineers are perfectly capable of managing entrepreneurial activities, mastering innovative ways of business development, when they spend time and efforts understanding and acting in the field. Engineers rely on science and methods for analysis to ensure the quality and liability of design; nevertheless a pinch of creativity is required in order to find innovative solutions for economic and e...

  2. Tokamak engineering mechanics

    CERN Document Server

    Song, Yuntao; Du, Shijun

    2013-01-01

    Tokamak Engineering Mechanics offers concise and thorough coverage of engineering mechanics theory and application for tokamaks, and the material is reinforced by numerous examples. Chapter topics include general principles, static mechanics, dynamic mechanics, thermal fluid mechanics and multiphysics structural mechanics of tokamak structure analysis. The theoretical principle of the design and the methods of the analysis for various components and load conditions are presented, while the latest engineering technologies are also introduced. The book will provide readers involved in the study

  3. Satellite communication engineering

    CERN Document Server

    Kolawole, Michael Olorunfunmi

    2013-01-01

    An undeniably rich and thorough guide to satellite communication engineering, Satellite Communication Engineering, Second Edition presents the fundamentals of information communications systems in a simple and succinct way. This book considers both the engineering aspects of satellite systems as well as the practical issues in the broad field of information transmission. Implementing concepts developed on an intuitive, physical basis and utilizing a combination of applications and performance curves, this book starts off with a progressive foundation in satellite technology, and then moves on

  4. Berger Engineering Complex

    Data.gov (United States)

    Federal Laboratory Consortium — Description/History: Engineering laboratory The Berger Lab Complex is a multi-purpose building with professional office, 100 seat auditorium, general purpose labs,...

  5. Strain-engineered MOSFETs

    CERN Document Server

    Maiti, CK

    2012-01-01

    Currently strain engineering is the main technique used to enhance the performance of advanced silicon-based metal-oxide-semiconductor field-effect transistors (MOSFETs). Written from an engineering application standpoint, Strain-Engineered MOSFETs introduces promising strain techniques to fabricate strain-engineered MOSFETs and to methods to assess the applications of these techniques. The book provides the background and physical insight needed to understand new and future developments in the modeling and design of n- and p-MOSFETs at nanoscale. This book focuses on recent developments in st

  6. Internal combustion piston engines

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C.L.

    1977-07-01

    Current worldwide production of internal combustion piston engines includes many diversified types of designs and a very broad range of sizes. Engine sizes range from a few horsepower in small mobile units to over 40,000 brake horsepower in large stationary and marine units. The key characteristics of internal combustion piston engines considered appropriate for use as prime movers in Integrated Community Energy Systems (ICES) are evaluated. The categories of engines considered include spark-ignition gas engines, compression-ignition oil (diesel) engines, and dual-fuel engines. The engines are evaluated with respect to full-load and part-load performance characteristics, reliability, environmental concerns, estimated 1976 cost data, and current and future status of development. The largest internal combustion piston engines manufactured in the United States range up to 13,540 rated brake horsepower. Future development efforts are anticipated to result in a 20 to 25% increase in brake horsepower without increase in or loss of weight, economy, reliability, or life expectancy, predicated on a simple extension of current development trends.

  7. Geothermal reservoir engineering

    CERN Document Server

    Grant, Malcolm Alister

    2011-01-01

    As nations alike struggle to diversify and secure their power portfolios, geothermal energy, the essentially limitless heat emanating from the earth itself, is being harnessed at an unprecedented rate.  For the last 25 years, engineers around the world tasked with taming this raw power have used Geothermal Reservoir Engineering as both a training manual and a professional reference.  This long-awaited second edition of Geothermal Reservoir Engineering is a practical guide to the issues and tasks geothermal engineers encounter in the course of their daily jobs. The bo

  8. Engineered Natural Systems Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — With its pressure vessels that simulate the pressures and temperatures found deep underground, NETL’s Engineered Natural Systems Laboratory in Pittsburgh, PA, gives...

  9. Bio Engineering Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Description/History: Chemistry and biology laboratories The Bio Engineering Laboratory (BeL) is theonly full spectrum biotechnology capability within the Department...

  10. Computer aided control engineering

    DEFF Research Database (Denmark)

    Szymkat, Maciej; Ravn, Ole

    1997-01-01

    Current developments in the field of Computer Aided Control Engineering (CACE) have a visible impact on the design methodologies and the structure of the software tools supporting them. Today control engineers has at their disposal libraries, packages or programming environments that may be speci......Current developments in the field of Computer Aided Control Engineering (CACE) have a visible impact on the design methodologies and the structure of the software tools supporting them. Today control engineers has at their disposal libraries, packages or programming environments that may...

  11. Metallurgical process engineering

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Ruiyu [Central Iron and Steel Research Institute (CISRI), Beijing (China)

    2011-07-01

    ''Metallurgical Process Engineering'' discusses large-scale integrated theory on the level of manufacturing production processes, putting forward concepts for exploring non-equilibrium and irreversible complex system. It emphasizes the dynamic and orderly operation of the steel plant manufacturing process, the major elements of which are the flow, process network and program. The book aims at establishing a quasi-continuous and continuous process system for improving several techno-economic indices, minimizing dissipation and enhancing the market competitiveness and sustainability of steel plants. The book is intended for engineers, researchers and managers in the fields of metallurgical engineering, industrial design, and process engineering. (orig.)

  12. Biomedical Engineering Desk Reference

    CERN Document Server

    Ratner, Buddy D; Schoen, Frederick J; Lemons, Jack E; Dyro, Joseph; Martinsen, Orjan G; Kyle, Richard; Preim, Bernhard; Bartz, Dirk; Grimnes, Sverre; Vallero, Daniel; Semmlow, John; Murray, W Bosseau; Perez, Reinaldo; Bankman, Isaac; Dunn, Stanley; Ikada, Yoshito; Moghe, Prabhas V; Constantinides, Alkis

    2009-01-01

    A one-stop Desk Reference, for Biomedical Engineers involved in the ever expanding and very fast moving area; this is a book that will not gather dust on the shelf. It brings together the essential professional reference content from leading international contributors in the biomedical engineering field. Material covers a broad range of topics including: Biomechanics and Biomaterials; Tissue Engineering; and Biosignal Processing* A hard-working desk reference providing all the essential material needed by biomedical and clinical engineers on a day-to-day basis * Fundamentals, key techniques,

  13. Bio Engineering Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — Description/History: Chemistry and biology laboratoriesThe Bio Engineering Laboratory (BeL) is theonly full spectrum biotechnology capability within the Department...

  14. Stirling Engine Heat Pump

    Science.gov (United States)

    Kagawa, Noboru

    Recent advances in the feasibility studies related to the Stirling engines and Stirling engine heat pumps which have been considered attractive due to their promising role in helping to solve the global environmental and energy problems,are reviewed. This article begins to describe the brief history of the Stirling engines and theoretical thermodynamic analysis of the Stirling cycle in order to understand several advantages on the Stirling engine. Furthermore,they could throw light on our question why the dream engines had not been promoted to practical applications during two hundred years. The present review shows that the Stirling engines with several unique advantages including 30 to 40% thermal efficiency and preferable exhaust characteristics,had been designed and constructed by recent tackling for the development of the advanced automobile and other applications using them. Based on the current state of art,it is being provided to push the Stirling engines combined with heat pumps based on the reversed Rankine cycle to the market. At present,however, many problems, especially for the durability, cost, and delicate engine parts must be enforced to solve. In addition,there are some possibilities which can increase the attractiveness of the Stirling engines and heat pumps. The review closes with suggestions for further research.

  15. Evaluating web serch engines

    CERN Document Server

    Lewandowski, Dirk

    2011-01-01

    Every month, more than 130 billion queries worldwide are entered into the search boxes of general-purpose web search engines (ComScore, 2010). This enormous number shows that web searching is not only a large business, but also that many people rely on the search engines' results when researching information. A goal of all search engine evaluation efforts is to generate better systems. This goal is of major importance to the search engine vendors who can directly apply evaluation results to develop better ranking algorithms.

  16. Cyber-Informed Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Robert S. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Benjamin, Jacob [Idaho National Lab. (INL), Idaho Falls, ID (United States); Wright, Virginia L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Quinones, Luis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Paz, Jonathan [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-03-01

    A continuing challenge for engineers who utilize digital systems is to understand the impact of cyber-attacks across the entire product and program lifecycle. This is a challenge due to the evolving nature of cyber threats that may impact the design, development, deployment, and operational phases of all systems. Cyber Informed Engineering is the process by which engineers are made aware of both how to use their engineering knowledge to positively impact the cyber security in the processes by which they architect and design components and the services and security of the components themselves.

  17. Mechanical engineers data handbook

    CERN Document Server

    Carvill, James

    1994-01-01

    This text provides the student and professional mechanical engineer with a reference text of an essentially practical nature. It is uncluttered by text, and extensive use of illustrations and tables provide quick and clear access to information. It alsoincludes examples of detailed calculations on many of the applications of technology used by mechanical and production engineers, draughtsmen and engineering designers.Although mainly intended for those studying and practising mechanical engineering, a glance at the contents will show that it is also useful to those in related br

  18. Biomechanics and mechanobiology in functional tissue engineering.

    Science.gov (United States)

    Guilak, Farshid; Butler, David L; Goldstein, Steven A; Baaijens, Frank P T

    2014-06-27

    The field of tissue engineering continues to expand and mature, and several products are now in clinical use, with numerous other preclinical and clinical studies underway. However, specific challenges still remain in the repair or regeneration of tissues that serve a predominantly biomechanical function. Furthermore, it is now clear that mechanobiological interactions between cells and scaffolds can critically influence cell behavior, even in tissues and organs that do not serve an overt biomechanical role. Over the past decade, the field of "functional tissue engineering" has grown as a subfield of tissue engineering to address the challenges and questions on the role of biomechanics and mechanobiology in tissue engineering. Originally posed as a set of principles and guidelines for engineering of load-bearing tissues, functional tissue engineering has grown to encompass several related areas that have proven to have important implications for tissue repair and regeneration. These topics include measurement and modeling of the in vivo biomechanical environment; quantitative analysis of the mechanical properties of native tissues, scaffolds, and repair tissues; development of rationale criteria for the design and assessment of engineered tissues; investigation of the effects biomechanical factors on native and repair tissues, in vivo and in vitro; and development and application of computational models of tissue growth and remodeling. Here we further expand this paradigm and provide examples of the numerous advances in the field over the past decade. Consideration of these principles in the design process will hopefully improve the safety, efficacy, and overall success of engineered tissue replacements. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Engine and method for operating an engine

    Science.gov (United States)

    Lauper, Jr., John Christian; Willi, Martin Leo; Thirunavukarasu, Balamurugesh; Gong, Weidong

    2008-12-23

    A method of operating an engine is provided. The method may include supplying a combustible combination of reactants to a combustion chamber of the engine, which may include supplying a first hydrocarbon fuel, hydrogen fuel, and a second hydrocarbon fuel to the combustion chamber. Supplying the second hydrocarbon fuel to the combustion chamber may include at least one of supplying at least a portion of the second hydrocarbon fuel from an outlet port that discharges into an intake system of the engine and supplying at least a portion of the second hydrocarbon fuel from an outlet port that discharges into the combustion chamber. Additionally, the method may include combusting the combustible combination of reactants in the combustion chamber.

  20. Advanced Natural Gas Reciprocating Engine(s)

    Energy Technology Data Exchange (ETDEWEB)

    Kwok, Doris; Boucher, Cheryl

    2009-09-30

    Energy independence and fuel savings are hallmarks of the nation’s energy strategy. The advancement of natural gas reciprocating engine power generation technology is critical to the nation’s future. A new engine platform that meets the efficiency, emissions, fuel flexibility, cost and reliability/maintainability targets will enable American manufacturers to have highly competitive products that provide substantial environmental and economic benefits in the US and in international markets. Along with Cummins and Waukesha, Caterpillar participated in a multiyear cooperative agreement with the Department of Energy to create a 50% efficiency natural gas powered reciprocating engine system with a 95% reduction in NOx emissions by the year 2013. This platform developed under this agreement will be a significant contributor to the US energy strategy and will enable gas engine technology to remain a highly competitive choice, meeting customer cost of electricity targets, and regulatory environmental standard. Engine development under the Advanced Reciprocating Engine System (ARES) program was divided into phases, with the ultimate goal being approached in a series of incremental steps. This incremental approach would promote the commercialization of ARES technologies as soon as they emerged from development and would provide a technical and commercial foundation of later-developing technologies. Demonstrations of the Phase I and Phase II technology were completed in 2004 and 2008, respectively. Program tasks in Phase III included component and system development and testing from 2009-2012. Two advanced ignition technology evaluations were investigated under the ARES program: laser ignition and distributed ignition (DIGN). In collaboration with Colorado State University (CSU), a laser ignition system was developed to provide ignition at lean burn and high boost conditions. Much work has been performed in Caterpillar’s DIGN program under the ARES program. This work