central engine activity: Topics by Science.gov

Sample records for central engine activity

The central equipment pool, an opportunity for improved technology management.

PubMed

Gentles, W M

2000-01-01

A model for a central equipment pool managed by a clinical engineering department has been presented. The advantages to patient care and to the clinical engineering department are many. The distribution of portable technology that has been traditionally managed by the materials management function is a logical match to the expanding role of clinical engineering departments in technology management. Accurate asset management tools have allowed us to provide reliable measures of infusion pump utilization, permitting us to predict future needs as programs expand. Thus we are more actively involved in strategic technology planning. The central equipment pool is an excellent opportunity for the clinical engineering department to increase its technology management activities.
Cooperation with Central and Eastern Europe in Language Engineering.

ERIC Educational Resources Information Center

Andersen, Poul

This paper outlines trends and activities in Central and Eastern European language research and language-related software development (language engineering) and briefly describes some specific projects. The language engineering segment of the European Union's Fourth Framework Programme, intended to facilitate use of telematics applications and…
Introduction: seismology and earthquake engineering in Central and South America.

USGS Publications Warehouse

Espinosa, A.F.

1983-01-01

Reports the state-of-the-art in seismology and earthquake engineering that is being advanced in Central and South America. Provides basic information on seismological station locations in Latin America and some of the programmes in strong-motion seismology, as well as some of the organizations involved in these activities.-from Author
Radio afterglow rebrightening: evidence for multiple active phases in gamma-ray burst central engines

NASA Astrophysics Data System (ADS)

Li, Long-Biao; Zhang, Zhi-Bin; Rice, Jared

2015-09-01

The rebrightening phenomenon is an interesting feature in some X-ray, optical, and radio afterglows of gamma-ray bursts (GRBs). Here, we propose a possible energy-supply assumption to explain the rebrightenings of radio afterglows, in which the central engine with multiple active phases can supply at least two GRB pulses in a typical GRB duration time. Considering the case of double pulses supplied by the central engine, the double pulses have separate physical parameters, except for the number density of the surrounding interstellar medium (ISM). Their independent radio afterglows are integrated by the ground detectors to form the rebrightening phenomenon. In this Letter, we firstly simulate diverse rebrightening light curves under consideration of different and independent physical parameters. Using this assumption, we also give our best fit to the radio afterglow of GRB 970508 at three frequencies of 1.43, 4.86, and 8.46 GHz. We suggest that the central engine may be active continuously at a timescale longer than that of a typical GRB duration time as many authors have suggested (e.g., Zhang et al., Astrophys. J. 787:66, 2014; Gao and Mészáros, Astrophys. J. 802:90, 2015), and that it may supply enough energy to cause the long-lasting rebrightenings observed in some GRB afterglows.
Central Engine Memory of Gamma-Ray Bursts and Soft Gamma-Ray Repeaters

NASA Astrophysics Data System (ADS)

Zhang, Bin-Bin; Zhang, Bing; Castro-Tirado, Alberto J.

2016-04-01

Gamma-ray bursts (GRBs) are bursts of γ-rays generated from relativistic jets launched from catastrophic events such as massive star core collapse or binary compact star coalescence. Previous studies suggested that GRB emission is erratic, with no noticeable memory in the central engine. Here we report a discovery that similar light curve patterns exist within individual bursts for at least some GRBs. Applying the Dynamic Time Warping method, we show that similarity of light curve patterns between pulses of a single burst or between the light curves of a GRB and its X-ray flare can be identified. This suggests that the central engine of at least some GRBs carries “memory” of its activities. We also show that the same technique can identify memory-like emission episodes in the flaring emission in soft gamma-ray repeaters (SGRs), which are believed to be Galactic, highly magnetized neutron stars named magnetars. Such a phenomenon challenges the standard black hole central engine models for GRBs, and suggest a common physical mechanism behind GRBs and SGRs, which points toward a magnetar central engine of GRBs.
Methodology for the systems engineering process. Volume 1: System functional activities

NASA Technical Reports Server (NTRS)

Nelson, J. H.

1972-01-01

Systems engineering is examined in terms of functional activities that are performed in the conduct of a system definition/design, and system development is described in a parametric analysis that combines functions, performance, and design variables. Emphasis is placed on identification of activities performed by design organizations, design specialty groups, as well as a central systems engineering organizational element. Identification of specific roles and responsibilities for doing functions, and monitoring and controlling activities within the system development operation are also emphasized.
Adiabatic expansion, early X-ray data and the central engine in GRBs

NASA Astrophysics Data System (ADS)

Barniol Duran, R.; Kumar, P.

2009-05-01

The Swift satellite early X-ray data show a very steep decay in most of the gamma-ray bursts light curves. This decay is either produced by the rapidly declining continuation of the central engine activity or by some leftover radiation starting right after the central engine shuts off. The latter scenario consists of the emission from an `ember' that cools via adiabatic expansion and, if the jet angle is larger than the inverse of the source Lorentz factor, the large angle emission. In this work, we calculate the temporal and spectral properties of the emission from such a cooling ember, providing a new treatment for the microphysics of the adiabatic expansion. We use the adiabatic invariance of p2⊥/B (p⊥ is the component of the electrons' momentum normal to the magnetic field, B) to calculate the electrons' Lorentz factor during the adiabatic expansion; the electron momentum becomes more and more aligned with the local magnetic field as the expansion develops. We compare the theoretical expectations of the adiabatic expansion (and the large angle emission) with the current observations of the early X-ray data and find that only ~20 per cent of our sample of 107 bursts are potentially consistent with this model. This leads us to believe that, for most bursts, the central engine does not turn off completely during the steep decay of the X-ray light curve; therefore, this phase is produced by the continued rapidly declining activity of the central engine.
CENTRAL ENGINE MEMORY OF GAMMA-RAY BURSTS AND SOFT GAMMA-RAY REPEATERS

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

Zhang, Bin-Bin; Castro-Tirado, Alberto J.; Zhang, Bing, E-mail: zhang.grb@gmail.com

Gamma-ray bursts (GRBs) are bursts of γ-rays generated from relativistic jets launched from catastrophic events such as massive star core collapse or binary compact star coalescence. Previous studies suggested that GRB emission is erratic, with no noticeable memory in the central engine. Here we report a discovery that similar light curve patterns exist within individual bursts for at least some GRBs. Applying the Dynamic Time Warping method, we show that similarity of light curve patterns between pulses of a single burst or between the light curves of a GRB and its X-ray flare can be identified. This suggests that themore » central engine of at least some GRBs carries “memory” of its activities. We also show that the same technique can identify memory-like emission episodes in the flaring emission in soft gamma-ray repeaters (SGRs), which are believed to be Galactic, highly magnetized neutron stars named magnetars. Such a phenomenon challenges the standard black hole central engine models for GRBs, and suggest a common physical mechanism behind GRBs and SGRs, which points toward a magnetar central engine of GRBs.« less
Prompt optical emission from gamma-ray bursts with multiple timescale variability of central engine activities

NASA Astrophysics Data System (ADS)

Xu, Si-Yao; Li, Zhuo

2014-04-01

Complete high-resolution light curves of GRB 080319B observed by Swift present an opportunity for detailed temporal analysis of prompt optical emission. With a two-component distribution of initial Lorentz factors, we simulate the dynamical process of shells being ejected from the central engine in the framework of the internal shock model. The emitted radiations are decomposed into different frequency ranges for a temporal correlation analysis between the light curves in different energy bands. The resulting prompt optical and gamma-ray emissions show similar temporal profiles, with both showing a superposition of a component with slow variability and a component with fast variability, except that the gamma-ray light curve is much more variable than its optical counterpart. The variability in the simulated light curves and the strong correlation with a time lag between the optical and gamma-ray emissions are in good agreement with observations of GRB 080319B. Our simulations suggest that the variations seen in the light curves stem from the temporal structure of the shells injected from the central engine of gamma-ray bursts. Future observations with high temporal resolution of prompt optical emission from GRBs, e.g., by UFFO-Pathfinder and SVOM-GWAC, will provide a useful tool for investigating the central engine activity.
Proceedings of the Flat-Plate Solar Array Project Research Forum on the Design of Flat-Plate Photovoltaic Arrays for Central Stations

NASA Technical Reports Server (NTRS)

1983-01-01

The Flat Plate Solar Array Project, focuses on advancing technologies relevant to the design and construction of megawatt level central station systems. Photovoltaic modules and arrays for flat plate central station or other large scale electric power production facilities require the establishment of a technical base that resolves design issues and results in practical and cost effective configurations. Design, qualification and maintenance issues related to central station arrays derived from the engineering and operating experiences of early applications and parallel laboratory reserch activities are investigated. Technical issues are examined from the viewpoint of the utility engineer, architect/engineer and laboratory researcher. Topics on optimum source circuit designs, module insulation design for high system voltages, array safety, structural interface design, measurements, and array operation and maintenance are discussed.
A plea for judgment.

PubMed

Davis, Michael

2012-12-01

Judgment is central to engineering, medicine, the sciences and many other practical activities. For example, one who otherwise knows what engineers know but lacks "engineering judgment" may be an expert of sorts, a handy resource much like a reference book or database, but cannot be a competent engineer. Though often overlooked or at least passed over in silence, the central place of judgment in engineering, the sciences, and the like should be obvious once pointed out. It is important here because it helps to explain where ethics fits into these disciplines. There is no good engineering, no good science, and so on without good judgment and no good judgment in these disciplines without ethics. Doing even a minimally decent job of teaching one of these disciplines necessarily includes teaching its ethics; teaching the ethics is teaching the discipline (or at least a large part of it).
UNIFYING THE ZOO OF JET-DRIVEN STELLAR EXPLOSIONS

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

Lazzati, Davide; Blackwell, Christopher H.; Morsony, Brian J.

We present a set of numerical simulations of stellar explosions induced by relativistic jets emanating from a central engine sitting at the center of compact, dying stars. We explore a wide range of durations of the central engine activity, two candidate stellar progenitors, and two possible values of the total energy release. We find that even if the jets are narrowly collimated, their interaction with the star unbinds the stellar material, producing a stellar explosion. We also find that the outcome of the explosion can be very different depending on the duration of the engine activity. Only the longest-lasting enginesmore » result in successful gamma-ray bursts. Engines that power jets only for a short time result in relativistic supernova (SN) explosions, akin to observed engine-driven SNe such as SN2009bb. Engines with intermediate durations produce weak gamma-ray bursts, with properties similar to nearby bursts such as GRB 980425. Finally, we find that the engines with the shortest durations, if they exist in nature, produce stellar explosions that lack sizable amounts of relativistic ejecta and are therefore dynamically indistinguishable from ordinary core-collapse SNe.« less
Engine Research Building’s Central Control Room

NASA Image and Video Library

1948-07-21

Operators in the Engine Research Building’s Central Control Room at the National Advisory Committee for Aeronautics (NACA) Lewis Flight Propulsion Laboratory. The massive 4.25-acre Engine Research Building contains dozens of test cells, test stands, and altitude chambers. A powerful collection of compressors and exhausters located in the central portion of the basement provided process air and exhaust for these test areas. This system is connected to similar process air systems in the laboratory’s other large test facilities. The Central Control Room coordinates this activity and communicates with the local utilities. This photograph was taken just after a major upgrade to the control room in 1948. The panels on the wall contain rudimentary floor plans of the different Engine Research Building sections with indicator lights and instrumentation for each test cell. The process air equipment included 12 exhausters, four compressors, a refrigeration system, cooling water, and an exhaust system. The operators in the control room kept in contact with engineers running the process air system and those conducting the tests in the test cells. The operators also coordinated with the local power companies to make sure enough electricity was available to operate the powerful compressors and exhausters.
Central Control Room in the Engine Research Building

NASA Image and Video Library

1968-11-21

Operators in the Engine Research Building’s Central Control Room at the National Aeronautics and Space Administration (NASA) Lewis Research Center. The massive 4.25-acre Engine Research Building contains dozens of test cells, test stands, and altitude chambers. A powerful a collection of compressors and exhausters located in the central portion of the basement provides process air and exhaust for these test areas. This system is connected to similar process air systems in the laboratory’s other large test facilities. The Central Control Room coordinates this activity and communicates with the local utilities. The panels on the wall contain schematics with indicator lights and instrumentation for the atmospheric exhaust, altitude exhaust, refrigerated air, and process air systems. The process air equipment included twelve exhausters, four compressors, refrigeration system, cooling water, and an exhaust system. The operators in the control room kept in contact with engineers running the process air system and those conducting the tests in the test cells. The operators also coordinated with the local power companies to make sure enough electricity was available to operate the powerful compressors and exhausters.
Nonthermal electron-positron pairs and cold matter in the central engines of active galactic nuclei

NASA Technical Reports Server (NTRS)

Zdziarski, Andrzej A.

1992-01-01

The nonthermal e(+/-) pair model of the central engine of active galactic nuclei (AGNs) is discussed. The model assumes that nonthermal e(+/-) pairs are accelerated to highly relativistic energies in a compact region close to the central black hole and in the vicinity of some cold matter. The model has a small number of free parameters and explains a large body of AGN observations from EUV to soft gamma-rays. In particular, the model explains the existence of the UV bump, the soft X-rays excess, the canonical hard X-ray power law, the spectral hardening above about 10 keV, and some of the variability patterns in the soft and hard X-rays. In addition, the model explains the spectral steepening above about 50 keV seen in NGC 4151.
Effects of Shocks on Emission from Central Engines of Active Galactic Nuclei. I

NASA Technical Reports Server (NTRS)

Sivron, R.; Caditz, D.; Tsuruta, S.

1996-01-01

In this paper we show that perturbations of the accretion flow within the central engines of some active galactic nuclei (AGNS) are likely to form shock waves in the accreting plasma. Such shocks, which may be either collisional or collisionless, can contribute to the observed high-energy temporal and spectral variability. Our rationale is the following: Observations show that the continuum emission probably originates in an optically thin, hot plasma in the AGN central engine. The flux and spectrum from this hot plasma varies significantly over light crossing timescales. Several authors have suggested that macroscopic perturbations contained within this plasma are the sources of this variability. In order to produce the observed emission the perturbations must be radiatively coupled with the optically thin hot matter and must also move with high velocities. We suggest that shocks, which can be very effective in randomizing the bulk motion of the perturbations, are responsible for this coupling. Shocks should form in the central engine, because the temperatures and magnetic fields are probably reduced below their virial values by radiative dissipation. Perturbations moving at Keplerian speeds, or strong non-linear excitations, result in supersonic and super-Alfvenic velocities leading to shock waves within the hot plasma. We show that even a perturbation smaller than the emitting region can form a shock that significantly modifies the continuum emission in an AGN, and that the spectral and temporal variability from such a shock generally resembles those of radio-quiet AGNS. As an example, the shock inducing perturbation in our model is a small main-sequence star, the capturing and eventual accretion of which are known to be a plausible process. We argue that shocks in the central engine may also provide a natural triggering mechanism for the "cold" component of Guilbert & Rees two-phase medium and an efficient mecha- nism for angular momentum transfer. Current and future missions, such as ASCA, XTE, XMM, AXAF, and ASTRO-E may determine the importance of shock-related emission from the central engines of AGNS.
Coherent Turbulence Rig in the Engine Research Building

NASA Image and Video Library

1979-08-21

An engineer examines the Coherent Turbulence Rig in the Engine Research Building at the National Aeronautics and Space Administration (NASA) Lewis Research Center. Coherent turbulence occurs when waves of uniform size and alignment are present in airflow. Researchers at NASA Lewis were interested in determining the relation between the size of the waves and their heat transfer properties. The massive 4.25-acre Engine Research Building contains dozens of test cells, test stands, and altitude chambers. A powerful a collection of compressors and exhausters located in the central portion of the basement provides process air and exhaust for these test areas. This system is connected to similar process air systems in the laboratory’s other large test facilities. The Central Control Room coordinates this activity and communicates with the local utilities.
Space construction activities

NASA Technical Reports Server (NTRS)

1991-01-01

The Center for Space Construction at the University of Colorado at Boulder was established in 1988 as a University Space Engineering Research Center. The mission of the Center is to conduct interdisciplinary engineering research which is critical to the construction of future space structures and systems and to educate students who will have the vision and technical skills to successfully lead future space construction activities. The research activities are currently organized around two central projects: Orbital Construction and Lunar Construction. Summaries of the research projects are included.
Unusual Central Engine Activity in the Double Burst GRB 110709B

NASA Technical Reports Server (NTRS)

Zhang, Bin-Bin; Burrows, David N.; Zhang, Bing; Meszaros, Peter; Stratta, Giulia; D'Elia, Valerio; Frederiks, Dmitry; Golenetskii, S.; Cummings, Jay R.; Wang, Xiang-Yu;

2011-01-01

The double burst, GRB 110709B, triggered Swift/BAT twice at 21:32:39 UT and 21:43:45 UT, respectively, on 9 July 2011. This is the first time we observed a GRB with two BAT triggers. In this paper, we present simultaneous Swift and Konus-WIND observations of this unusual GRB and its afterglow. If the two events are from the same physical origin, their different time-dependent spectral evolution suggest they must belong to different episodes of the central engine, which may be a magnetar-to-BH accretion system.

A Temporal Correlation in Quiescent Gamma-Ray Burst Prompt Emission: Evidence for Prognitor Memory

NASA Astrophysics Data System (ADS)

Patton, Thomas L.; Giblin, Timothy; Hakkila, Jon E.

2018-06-01

In spite of the insight gained into the nature of the Gamma-Ray Bursts (GRB) from early and late-time X-Ray observations in the Swift era, GRB prompt emission continues to provide clues and new insight into the activity of the central engine. A comprehensive understanding of all emission components observed in GRBs, from the traditional prompt GRB emission to the long lived X-Ray and optical decay super- imposed with late-time flaring activity, currently remains allusive. Using data from the Swift Burst Alert Telescope (BAT), we've identified and measured durations observed in GRBs that exhibit multi-episodic prompt emission behavior. Duration analysis of the burst attributes revealed no significant correlations between emissions and quiet time durations. This variability allows us to extrapolate that the central engine is constantly active.

Blending Education and Polymer Science: Semiautomated Creation of a Thermodynamic Property Database

ERIC Educational Resources Information Center

Tchoua, Roselyne B.; Qin, Jian; Audus, Debra J.; Chard, Kyle; Foster, Ian T.; de Pablo, Juan

2016-01-01

Structured databases of chemical and physical properties play a central role in the everyday research activities of scientists and engineers. In materials science, researchers and engineers turn to these databases to quickly query, compare, and aggregate various properties, thereby allowing for the development or application of new materials. The…
Theoretical and Observational Studies of the Central Engines of AGN

NASA Technical Reports Server (NTRS)

Sivron, Ran

1995-01-01

In Active Galactic Nuclei (AGN) the luminosity is so intense that the effect of radiation pressure on a particle may exceed the gravitational attraction. It was shown that when such luminosities are reached, relatively cold (not completely ionized) thermal matter clouds may form in the central engines of AGN, where most of the luminosity originates. We show that the spectrum of emission from cold clouds embedded in hot relativistic matter is similar to the observed spectrum. We also show that within the hot relativistic matter, cold matter moves faster than the speed of sound or the Alfven speed, and shocks form. The shocks provide a mechanism by which a localized perturbation can propagate throughout the central engine. The shocked matter can emit the observed luminosity, and can explain the flux and spectral variability. It may also provide an efficient mechanism for the outward transfer of angular momentum and provide the outward flow of winds. With observations from X-ray satellites, emission features from the cold and hot matter may be revealed. Our analysis of X-ray data from the Seyfert 1 galaxy MCG - 6-30-15 over five years using detectors on the Ginga and Rosat satellites, revealed some interesting variable features. A source with hot matter emits non-thermal radiation which is Compton reflected from cold matter and then absorbed by warm (partially ionized) absorbing matter in the first model, which can be fit to the data if both the cold and warm absorbers are near the central engine. An alternative model in which the emission from the hot matter is partially covered by very warm matter (in which all elements except Iron are mostly ionized) is also successful. In this model the cold and warm matter may be at distances of up to 100 times the size of the central engine, well within the region where broad optical lines are produced. The flux variability is more naturally explained by the second model. Our results support the existence of cold matter in, or near, the central engine of MCG -6-30-15. Cold matter in the central engine, and evidence of the effects of shocks, is probably forthcoming with future X-ray satellites.
Bright x-ray flares in gamma-ray burst afterglows.

PubMed

Burrows, D N; Romano, P; Falcone, A; Kobayashi, S; Zhang, B; Moretti, A; O'brien, P T; Goad, M R; Campana, S; Page, K L; Angelini, L; Barthelmy, S; Beardmore, A P; Capalbi, M; Chincarini, G; Cummings, J; Cusumano, G; Fox, D; Giommi, P; Hill, J E; Kennea, J A; Krimm, H; Mangano, V; Marshall, F; Mészáros, P; Morris, D C; Nousek, J A; Osborne, J P; Pagani, C; Perri, M; Tagliaferri, G; Wells, A A; Woosley, S; Gehrels, N

2005-09-16

Gamma-ray burst (GRB) afterglows have provided important clues to the nature of these massive explosive events, providing direct information on the nearby environment and indirect information on the central engine that powers the burst. We report the discovery of two bright x-ray flares in GRB afterglows, including a giant flare comparable in total energy to the burst itself, each peaking minutes after the burst. These strong, rapid x-ray flares imply that the central engines of the bursts have long periods of activity, with strong internal shocks continuing for hundreds of seconds after the gamma-ray emission has ended.
Late-time X-rays to map the Zoo of Engine-driven Stellar Explosions

NASA Astrophysics Data System (ADS)

Margutti, Raffaella

2017-09-01

We propose a continuation of our effort to monitor nearby long GRBs (z <=0.3) with Chandra. Our synergistic multi-wavelength program (radio, optical, Swift and proposed Chandra) is designed to extract the true energy of these explosions and to reveal the activity of their central engines. This effort allows us to: (i) investigate whether sub-energetic GRBs share the same explosion mechanisms and central engines as ordinary GRBs; (ii) investigate what essential physical property enables only a small fraction of supernovae to harbor a relativistic outflow; (iii) understand if jet-driven explosions are common in all SNe. These objectives are only possible by expanding the current small sample of well-observed local GRBs and by drawing comparisons with cosmological GRBs and common SNe.
Theories of central engine for long gamma-ray bursts

NASA Astrophysics Data System (ADS)

Nagataki, Shigehiro

2018-02-01

Long GRBs are the most powerful explosions in the universe since the Big Bang. At least, some fraction of long GRBs are born from the death of massive stars. Likewise, only some fraction of massive stars that satisfy additional special conditions explode as long GRBs associated with supernovae/hypernovae. In this paper, we discuss the explosion mechanism of long GRBs associated with hypernovae: ‘the central engine of long GRBs’. The central engine of long GRBs is very different from that of core-collapse supernovae, although the mechanism of the engine is still not firmly established. In this paper, we review theoretical studies of the central engine of long GRBs. First, we discuss possible progenitor stars. Then several promising mechanisms of the central engine—such as black hole and magnetar formation—will be reviewed. We will also mention some more exotic models. Finally, we describe prospects for future studies of the central engine of long GRBs.
A possible relation between flare activity in super-luminous supernovae and gamma-ray bursts

NASA Astrophysics Data System (ADS)

Yu, Yun-Wei; Li, Shao-Ze

2017-09-01

Significant undulations appear in the light curve of a recently discovered super-luminous supernova (SLSN) SN 2015bn after the first peak, while the underlying profile of the light curve can be explained well by a continuous energy supply from a central engine, possibly the spin-down of a millisecond magnetar. We propose that these undulations are caused by an intermittent pulsed energy supply, indicating the energetic flare activity of the central engine of the SLSN. Many post-burst flares were discovered during X-ray afterglow observations of gamma-ray bursts (GRBs). We find that the SLSN flares described here approximately obey the empirical correlation between the luminosity and time-scale of GRB flares, extrapolated to the relevant longer time-scales of SLSN flares. This somewhat confirms the possible connection between these two different phenomena, as recently suggested by Yu et al.
APPALACHIAN FOLDS, LATERAL RAMPS, AND BASEMENT FAULTS: A MODERN ENGINEERING PROBLEM?

USGS Publications Warehouse

Pohn, Howard A.

1987-01-01

Field studies and analysis of radar data have shown that cross-strike faulting in the central and southern Appalachians has affected geologic structures at the surface. These basement faults appear to have been active through much of geologic time. Indeed, more than 45 percent of modern earthquakes occur along these narrow zones here termed 'lateral ramps. ' Because of this seismic activity, these lateral ramps are likely to be zones that are prone to slope failure. The engineer should be aware of the presence of such zones and the higher landslide potential along them.
Establishing a `Centre for Engineering Experimentation and Design Simulation': a step towards restructuring engineering education in India

NASA Astrophysics Data System (ADS)

Venkateswarlu, P.

2017-07-01

Reforms in undergraduate engineering curriculum to produce engineers with entrepreneurial skills should address real-world problems relevant to industry and society with active industry support. Technology-assisted, hands-on projects involving experimentation, design simulation and prototyping will transform graduates into professionals with necessary skills to create and advance knowledge that meets global standards. To achieve this goal, this paper proposes establishing a central facility, 'Centre for Engineering Experimentation and Design Simulation' (CEEDS) in autonomous engineering colleges in India. The centre will be equipped with the most recent technology resources and computational facilities where students execute novel interdisciplinary product-oriented projects benefiting both industry and society. Students undertake two projects: a short-term project aimed at an engineering solution to a problem in energy, health and environment and the other a major industry-supported project devoted to a product that enhances innovation and creativity. The paper presents the current status, the theoretical and pedagogical foundation for the centre's relevance, an activity plan and its implementation in the centre for product-based learning with illustrative examples.
Broad-band emission properties of central engine powered supernova ejecta interacting with a circumstellar medium

NASA Astrophysics Data System (ADS)

Suzuki, Akihiro; Maeda, Keiichi

2018-04-01

We investigate broad-band emission from supernova ejecta powered by a relativistic wind from a central compact object. A recent two-dimensional hydrodynamic simulation studying the dynamical evolution of supernova ejecta with a central energy source has revealed that outermost layers of the ejecta are accelerated to mildly relativistic velocities because of the breakout of a hot bubble driven by the energy injection. The outermost layers decelerate as they sweep a circumstellar medium surrounding the ejecta, leading to the formation of the forward and reverse shocks propagating in the circumstellar medium and the ejecta. While the ejecta continue to release the internal energy as thermal emission from the photosphere, the energy dissipation at the forward and reverse shock fronts gives rise to non-thermal emission. We calculate light curves and spectral energy distributions of thermal and non-thermal emission from central engine powered supernova ejecta embedded in a steady stellar wind with typical mass loss rates for massive stars. The light curves are compared with currently available radio and X-ray observations of hydrogen-poor superluminous supernovae, as well as the two well-studied broad-lined Ic supernovae, 1998bw and 2009bb, which exhibit bright radio emission indicating central engine activities. We point out that upper limits on radio luminosities of nearby superluminous supernovae may indicate the injected energy is mainly converted to thermal radiation rather than creating mildly relativistic flows owing to photon diffusion time scales comparable to the injection time scale.
The Invention Studio: A University Maker Space and Culture

ERIC Educational Resources Information Center

Forest, Craig R.; Moore, Roxanne A.; Jariwala, Amit S.; Fasse, Barbara Burks; Linsey, Julie; Newstetter, Wendy; Ngo, Peter; Quintero, Christopher

2014-01-01

Creativity, invention, and innovation are values championed as central pillars of engineering education. However, university environments that foster open-ended design-build projects are uncommon. Fabrication and prototyping spaces at universities are typically "machine shops" where students relinquish actual fabrication activities to…
Radial Angular Momentum Transfer and Magnetic Barrier for Short-type Gamma-Ray-burst Central Engine Activity

NASA Astrophysics Data System (ADS)

Liu, Tong; Liang, En-Wei; Gu, Wei-Min; Hou, Shu-Jin; Lei, Wei-Hua; Lin, Lin; Dai, Zi-Gao; Zhang, Shuang-Nan

2012-11-01

Soft extended emission (EE) following initial hard spikes up to 100 s was observed with Swift/BAT for about half of known short-type gamma-ray bursts (SGRBs). This challenges the conversional central engine models of SGRBs, i.e., compact star merger models. In the framework of black-hole-neutron-star merger models, we study the roles of radial angular momentum transfer in the disk and the magnetic barrier around the black hole in the activity of SGRB central engines. We show that radial angular momentum transfer may significantly prolong the lifetime of the accretion process, which may be divided into multiple episodes by the magnetic barrier. Our numerical calculations based on models of neutrino-dominated accretion flows suggest that disk mass is critical for producing the observed EE. In the case of the mass being ~0.8 M ⊙, our model can reproduce the observed timescale and luminosity of both the main and the EE episodes in a reasonable parameter set. The predicted luminosity of the EE component is lower than the observed EE within about one order of magnitude and the timescale is shorter than 20 s if the disk mass is ~0.2 M ⊙. Swift/BAT-like instruments may be not sensitive enough to detect the EE component in this case. We argue that the EE component could be a probe for the merger process and disk formation for compact star mergers.
Integrating the protein and metabolic engineering toolkits for next-generation chemical biosynthesis.

PubMed

Pirie, Christopher M; De Mey, Marjan; Jones Prather, Kristala L; Ajikumar, Parayil Kumaran

2013-04-19

Through microbial engineering, biosynthesis has the potential to produce thousands of chemicals used in everyday life. Metabolic engineering and synthetic biology are fields driven by the manipulation of genes, genetic regulatory systems, and enzymatic pathways for developing highly productive microbial strains. Fundamentally, it is the biochemical characteristics of the enzymes themselves that dictate flux through a biosynthetic pathway toward the product of interest. As metabolic engineers target sophisticated secondary metabolites, there has been little recognition of the reduced catalytic activity and increased substrate/product promiscuity of the corresponding enzymes compared to those of central metabolism. Thus, fine-tuning these enzymatic characteristics through protein engineering is paramount for developing high-productivity microbial strains for secondary metabolites. Here, we describe the importance of protein engineering for advancing metabolic engineering of secondary metabolism pathways. This pathway integrated enzyme optimization can enhance the collective toolkit of microbial engineering to shape the future of chemical manufacturing.
Remote sensing, imaging, and signal engineering

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

Brase, J.M.

1993-03-01

This report discusses the Remote Sensing, Imaging, and Signal Engineering (RISE) trust area which has been very active in working to define new directions. Signal and image processing have always been important support for existing programs at Lawrence Livermore National Laboratory (LLNL), but now these technologies are becoming central to the formation of new programs. Exciting new applications such as high-resolution telescopes, radar remote sensing, and advanced medical imaging are allowing us to participate in the development of new programs.
The dynamics and fueling of active nuclei

NASA Technical Reports Server (NTRS)

Norman, C.; Silk, J.

1983-01-01

It is generally believed that quasars and active galactic nuclei produce their prodigious luminosities in connection with the release of gravitational energy associated with accretion and infall of matter onto a compact central object. In the present analysis, it is assumed that the central object is a massive black hole. The fact that a black hole provides the deepest possible central potential well does imply that it is the most natural candidate for the central engine. It is also assumed that the quasar is associated with the nucleus of a conventional galaxy. A number of difficulties arise in connection with finding a suitable stellar fueling model. A simple scheme is discussed for resolving these difficulties. Attention is given to fueling in a nonaxisymmetric potential, the effects of a massive accretion disk, and the variability in the disk luminosity caused by star-disk collisions assuming that the energy deposited in the disk is radiated.
Annual INTEC Groundwater Monitoring Report for Group 5 - Snake River Plain Aquifer (2001)

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

Roddy, Michael Scott

2002-02-01

This report describes the monitoring activities conducted and presents the results of groundwater sampling and water-level measurements from October 2000 to September 2001. Groundwater samples were initially collected from 41 wells from the Idaho Nuclear Technology and Engineering Center and the Central Facilities Area and analyzed for iodine-129, strontium-90, tritium, gross alpha, gross beta, technetium-99, uranium isotopes, plutonium isotopes, neptunium-237, americium-241, gamma spectrometry, and mercury. Samples from 41 wells were collected in April and May 2001. Additional sampling was conducted in August 2001 and included the two CFA production wells, the CFA point of compliance for the production wells, onemore » well that was previously sampled and five additional monitoring wells. Iodine-129 and strontium-90 were the only analytes above their respective maximum contaminant levels. Iodine-129 was detected just above its maximum contaminant level of 1 pCi/L at two of the Central Facilities Area landfill wells. Iodine-129 was detected in the CFA production wells at 0.35±0.083 pCi/L in CFA-1, but was below detectable activity in CFA-2. Strontium-90 was above its maximum contaminant level of 8 pCi/L in several wells near the Idaho Nuclear Technology and Engineering Center but was below its maximum contaminant level in the downgradient wells at the Central Facilities Area landfills. Sr-90 was not detected in the CFA production wells. Gross beta results generally mirrored the results for strontium-90 and technetium-99. Plutonium isotopes and neptunium-237 were not detected. Uranium-233/234 and uranium-238 isotopes were detected in all samples. Concentrations of background and site wells were similar and are within background limits for total uranium determined by the USGS, suggesting that the concentrations are background. Uranium-235/236 was detected in 11 samples, but all the detected concentrations were similar and near the minimum detectable activity. Americium-241 was detected at three locations near the minimum detectable activity of approximately 0.07 pCi/L. The gamma spectrometry results detected cesium-137 in three samples, potassium-40 at eight locations, and radium-226 at one location. Mercury was below its maximum contaminant level of 2 µg/L in all samples. Gamma spectrometry results for the CFA production wells did not detect any analytes. Water-level measurements were taken from wells in the Idaho Nuclear Technology and Engineering Center, Central Facilities Area, and the area south of Central Facilities Area to evaluate groundwater flow directions. Water-level measurements indicated groundwater flow to the south-southwest from the Idaho Nuclear Technology and Engineering Center.« less
Revealing Physical Activity of GRB Central Engine with Macronova/Kilonova Data

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

Shen, Zhao-Qiang; Jin, Zhi-Ping; Liang, Yun-Feng

The modeling of Li-Paczyński macronova/kilonova signals gives a reasonable estimate on the neutron-rich material ejected during the neutron star mergers. Usually the accretion disk is more massive than the macronova ejecta, with which the efficiencies of converting the disk mass into prompt emission of three merger-driven GRBs can hence be directly constrained. Supposing the macronovae/kilonovae associated with GRB 050709, GRB 060614, and GRB 130603B arose from radioactive decay of the r -process material, the upper limit on energy conversion efficiencies are found to be as low as ∼10{sup −6}–10{sup −4}. Moreover, for all three events, neutrino annihilation is likely powerfulmore » enough to account for the brief gamma-ray flashes. Neutrino annihilation can also explain the “extended” emission lasting ∼100 s in GRB 050709, but does not work for the one in GRB 060614. These progresses demonstrate that the macronova can serve as a novel probe of the central engine activity.« less
8. ENGINE TEST CELL BUILDING INTERIOR. LONGITUDINAL CENTRAL PASSAGEWAY IN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. ENGINE TEST CELL BUILDING INTERIOR. LONGITUDINAL CENTRAL PASSAGEWAY IN BASEMENT. LOOKING SOUTHWEST. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA
5. ENGINE TEST CELL BUILDING INTERIOR. CENTRAL ROOM ON MAIN ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. ENGINE TEST CELL BUILDING INTERIOR. CENTRAL ROOM ON MAIN FLOOR. LOOKING NORTHWEST. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA
6. ENGINE TEST CELL BUILDING INTERIOR. CENTRAL OFFICE AREA ON ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. ENGINE TEST CELL BUILDING INTERIOR. CENTRAL OFFICE AREA ON BASEMENT LEVEL. LOOKING WEST. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA
Model-Based Systems Engineering for Capturing Mission Architecture System Processes with an Application Case Study - Orion Flight Test 1

NASA Technical Reports Server (NTRS)

Bonanne, Kevin H.

2011-01-01

Model-based Systems Engineering (MBSE) is an emerging methodology that can be leveraged to enhance many system development processes. MBSE allows for the centralization of an architecture description that would otherwise be stored in various locations and formats, thus simplifying communication among the project stakeholders, inducing commonality in representation, and expediting report generation. This paper outlines the MBSE approach taken to capture the processes of two different, but related, architectures by employing the Systems Modeling Language (SysML) as a standard for architecture description and the modeling tool MagicDraw. The overarching goal of this study was to demonstrate the effectiveness of MBSE as a means of capturing and designing a mission systems architecture. The first portion of the project focused on capturing the necessary system engineering activities that occur when designing, developing, and deploying a mission systems architecture for a space mission. The second part applies activities from the first to an application problem - the system engineering of the Orion Flight Test 1 (OFT-1) End-to-End Information System (EEIS). By modeling the activities required to create a space mission architecture and then implementing those activities in an application problem, the utility of MBSE as an approach to systems engineering can be demonstrated.

Advances in Distributed Operations and Mission Activity Planning for Mars Surface Exploration

NASA Technical Reports Server (NTRS)

Fox, Jason M.; Norris, Jeffrey S.; Powell, Mark W.; Rabe, Kenneth J.; Shams, Khawaja

2006-01-01

A centralized mission activity planning system for any long-term mission, such as the Mars Exploration Rover Mission (MER), is completely infeasible due to budget and geographic constraints. A distributed operations system is key to addressing these constraints; therefore, future system and software engineers must focus on the problem of how to provide a secure, reliable, and distributed mission activity planning system. We will explain how Maestro, the next generation mission activity planning system, with its heavy emphasis on portability and distributed operations has been able to meet these design challenges. MER has been an excellent proving ground for Maestro's new approach to distributed operations. The backend that has been developed for Maestro could benefit many future missions by reducing the cost of centralized operations system architecture.
DOE Office of Scientific and Technical Information (OSTI.GOV)

Xie, Wei; Lei, Wei-Hua; Wang, Ding-Xiong, E-mail: leiwh@hust.edu.cn

Recently, two empirical correlations related to the minimum variability timescale (MTS) of the light curves are discovered in gamma-ray bursts (GRBs). One is the anti-correlation between MTS and Lorentz factor Γ, and the other is the anti-correlation between the MTS and gamma-ray luminosity L {sub γ}. Both of the two correlations might be used to explore the activity of the central engine of GRBs. In this paper, we try to understand these empirical correlations by combining two popular black hole central engine models (namely, the Blandford and Znajek mechanism (BZ) and the neutrino-dominated accretion flow (NDAF)). By taking the MTSmore » as the timescale of viscous instability of the NDAF, we find that these correlations favor the scenario in which the jet is driven by the BZ mechanism.« less
Collapsar γ-ray bursts: how the luminosity function dictates the duration distribution

NASA Astrophysics Data System (ADS)

Petropoulou, Maria; Barniol Duran, Rodolfo; Giannios, Dimitrios

2017-12-01

Jets in long-duration γ-ray bursts (GRBs) have to drill through the collapsing star in order to break out of it and produce the γ-ray signal while the central engine is still active. If the breakout time is shorter for more powerful engines, then the jet-collapsar interaction acts as a filter of less luminous jets. We show that the observed broken power-law GRB luminosity function is a natural outcome of this process. For a theoretically motivated breakout time that scales with jet luminosity as L-χ with χ ∼ 1/3-1/2, we show that the shape of the γ-ray duration distribution can be uniquely determined by the GRB luminosity function and matches the observed one. This analysis has also interesting implications about the supernova-central engine connection. We show that not only successful jets can deposit sufficient energy in the stellar envelope to power the GRB-associated supernovae, but also failed jets may operate in all Type Ib/c supernovae.
7. ENGINE TEST CELL BUILDING INTERIOR. WALL MAP IN CENTRAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. ENGINE TEST CELL BUILDING INTERIOR. WALL MAP IN CENTRAL BASEMENT OFFICE AREA. LOOKING SOUTHWEST. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA
Bioinstrumentation: A Project-Based Engineering Course

ERIC Educational Resources Information Center

Kyle, Aaron M.; Jangraw, David C.; Bouchard, Matthew B.; Downs, Matthew E.

2016-01-01

This paper presents the development, implementation, and assessment of a project-based Bioinstrumentation course. All course lectures and hands-on laboratory activities are related to a central project theme: a cardiac pacemaker. The students create a benchtop cardiac pacemaker by applying instrumentation knowledge acquired in the course to each…
Near-IR 2D-spectroscopy of the 4''x 4'' region around the Active Galactic Nucleus of NGC 1068 with ISAAC/VLT

NASA Astrophysics Data System (ADS)

Galliano, E.; Alloin, D.

2002-10-01

New near-IR long slit spectroscopic data obtained with ISAAC on VLT/ANTU (ESO/Paranal) complement and extend our previously published near-IR data (Alloin et al. \\cite{all01}) to produce Brgamma and H2 emission line maps and line profile grids of the central 4'' x 4'' region surrounding the central engine of NGC 1068. The seeing quality together with the use of an 0.3'' wide slit and 0.3'' slit position offsets allow one to perform 2D-spectroscopy at a spatial resolution ~ 0.5''. Slit orientations (PA = 102 degr and PA = 12 degr) were chosen so as to match respectively the equatorial plane and the axis of the suspected molecular/dusty torus in NGC 1068. The selected wavelength range from 2.1 to 2.2μm is suitable to detect and analyze the Brgamma and H2 emission lines at a spectral resolution corresponding to 35km s-1. An asymmetric distribution of H2 emission around the continuum peak is observed. No H2 emission is detected at the location of the strong 2.2μm continuum core (coincident within error-bars with the central engine location), while two conspicuous knots of H2 emission are detected at about 1'' on each side of the central engine along PA = 90 degr, with a projected velocity difference of 140km s-1: this velocity jump has been interpreted in Alloin et al. (\\cite{all01}) as the signature of a rotating disk of molecular material. From this new data set, we find that only very low intensity Brgamma emission is detected at the location of the two main knots of H2 emission. Another knot with both H2 and Brgamma emission is detected to the North of the central engine, close to the radio source C where the small scale radio jet is redirected and close to the brightest [OIII] cloud NLR-B. It has a counterpart to the South, placed almost symmetrically with respect to the central engine, although mainly visible in the Brgamma emission. The northern and southern knots appear to be related to the ionization cone. At the achieved spectral resolution, the H2 emission line profiles appear highly asymmetric with their low velocity wing being systematically more extended than their high velocity wing. A simple way to account for the changes of the H2 line profiles (peak-shift with respect to the systemic velocity, width, asymmetry) over the entire 4'' x 4'' region, is to consider that a radial outflow is superimposed over the emission of the rotating molecular disk. We present a model of such a kinematical configuration and compare our predicted H2 emission profiles to the observed ones. Excitation of the H2 line is briefly discussed: X-ray irradiation from the central engine is found to be the most likely source of excitation. Given the fact that the material obscuring our direct view toward the central engine is Compton thick (NH >= 1024 {cm-2}), the observed location of the main H2 knots at a distance of 70 pc from the central engine suggests that the rotating molecular disk is warped. Based on observations collected at the ESO/Paranal 8 m UT1 telescope, Proposals 63.P-0167A & 66.B-0142A.
Engineering: Defining and differentiating its unique culture

NASA Astrophysics Data System (ADS)

Pilotte, Mary K.

The world of work for engineering professionals is changing. At a rapid pace, experienced engineers are exiting the workforce due to retirement of the Baby Boomer generation, while at the same time the problems facing engineers are increasingly complex and frequently global in nature. For firms to protect their knowledge assets, they must ensure that acquired understandings are shared among their engineering work groups. Engineering teaching and learning in the workplace (i.e., knowledge sharing), is a social activity that resides in a social context governed by the professional engineering culture. This quantitative study uses Hofstede's Organizational Cultural Values Model (Hofstede, Neuijen, Ohayv, & Sanders, 1990) to examine dimensions of engineering culture in the workplace, producing a central tendency profile of engineering's cultural practices. Further, it explores through hypotheses if demographic differentiators, including birth generation, gender, race, industry sector of employment, and engineering discipline, play roles in forming engineering cultural practices. Results both corroborate aspects of Hofstede's model and assert new understandings relative to factors influencing dimensions of engineering practice. Outcomes are discussed in terms of their potential impact on industrial knowledge sharing and formation of beneficial engineering cultures.
Creating metabolic demand as an engineering strategy in Pseudomonas putida - Rhamnolipid synthesis as an example.

PubMed

Tiso, Till; Sabelhaus, Petra; Behrens, Beate; Wittgens, Andreas; Rosenau, Frank; Hayen, Heiko; Blank, Lars Mathias

2016-12-01

Metabolic engineering of microbial cell factories for the production of heterologous secondary metabolites implicitly relies on the intensification of intracellular flux directed toward the product of choice. Apart from reactions following peripheral pathways, enzymes of the central carbon metabolism are usually targeted for the enhancement of precursor supply. In Pseudomonas putida , a Gram-negative soil bacterium, central carbon metabolism, i.e., the reactions required for the synthesis of all 12 biomass precursors, was shown to be regulated at the metabolic level and not at the transcriptional level. The bacterium's central carbon metabolism appears to be driven by demand to react rapidly to ever-changing environmental conditions. In contrast, peripheral pathways that are only required for growth under certain conditions are regulated transcriptionally. In this work, we show that this regulation regime can be exploited for metabolic engineering. We tested this driven-by-demand metabolic engineering strategy using rhamnolipid production as an example. Rhamnolipid synthesis relies on two pathways, i.e., fatty acid de novo synthesis and the rhamnose pathway, providing the required precursors hydroxyalkanoyloxy-alkanoic acid (HAA) and activated (dTDP-)rhamnose, respectively. In contrast to single-pathway molecules, rhamnolipid synthesis causes demand for two central carbon metabolism intermediates, i.e., acetyl-CoA for HAA and glucose-6-phosphate for rhamnose synthesis. Following the above-outlined strategy of driven by demand, a synthetic promoter library was developed to identify the optimal expression of the two essential genes ( rhlAB ) for rhamnolipid synthesis. The best rhamnolipid-synthesizing strain had a yield of 40% rhamnolipids on sugar [Cmol RL /Cmol Glc ], which is approximately 55% of the theoretical yield. The rate of rhamnolipid synthesis of this strain was also high. Compared to an exponentially growing wild type, the rhamnose pathway increased its flux by 300%, whereas the flux through de novo fatty acid synthesis increased by 50%. We show that the central carbon metabolism of P. putida is capable of meeting the metabolic demand generated by engineering transcription in peripheral pathways, thereby enabling a significant rerouting of carbon flux toward the product of interest, in this case, rhamnolipids of industrial interest.
Incorporating global components into ethics education.

PubMed

Wang, George; Thompson, Russell G

2013-03-01

Ethics is central to science and engineering. Young engineers need to be grounded in how corporate social responsibility principles can be applied to engineering organizations to better serve the broader community. This is crucial in times of climate change and ecological challenges where the vulnerable can be impacted by engineering activities. Taking a global perspective in ethics education will help ensure that scientists and engineers can make a more substantial contribution to development throughout the world. This paper presents the importance of incorporating the global and cross culture components in the ethic education. The authors bring up a question to educators on ethics education in science and engineering in the globalized world, and its importance, necessity, and impendency. The paper presents several methods for discussion that can be used to identify the differences in ethics standards and practices in different countries; enhance the student's knowledge of ethics in a global arena.
Engineering central metabolism - a grand challenge for plant biologists.

PubMed

Sweetlove, Lee J; Nielsen, Jens; Fernie, Alisdair R

2017-05-01

The goal of increasing crop productivity and nutrient-use efficiency is being addressed by a number of ambitious research projects seeking to re-engineer photosynthetic biochemistry. Many of these projects will require the engineering of substantial changes in fluxes of central metabolism. However, as has been amply demonstrated in simpler systems such as microbes, central metabolism is extremely difficult to rationally engineer. This is because of multiple layers of regulation that operate to maintain metabolic steady state and because of the highly connected nature of central metabolism. In this review we discuss new approaches for metabolic engineering that have the potential to address these problems and dramatically improve the success with which we can rationally engineer central metabolism in plants. In particular, we advocate the adoption of an iterative 'design-build-test-learn' cycle using fast-to-transform model plants as test beds. This approach can be realised by coupling new molecular tools to incorporate multiple transgenes in nuclear and plastid genomes with computational modelling to design the engineering strategy and to understand the metabolic phenotype of the engineered organism. We also envisage that mutagenesis could be used to fine-tune the balance between the endogenous metabolic network and the introduced enzymes. Finally, we emphasise the importance of considering the plant as a whole system and not isolated organs: the greatest increase in crop productivity will be achieved if both source and sink metabolism are engineered. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.
* Central Growth Factor Loaded Depots in Bone Tissue Engineering Scaffolds for Enhanced Cell Attraction.

PubMed

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 bone formation.
THREE-DIMENSIONAL SIMULATIONS OF LONG DURATION GAMMA-RAY BURST JETS: TIMESCALES FROM VARIABLE ENGINES

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

López-Cámara, D.; Lazzati, Davide; Morsony, Brian J., E-mail: diego@astro.unam.mx

2016-08-01

Gamma-ray burst (GRB) light curves are characterized by marked variability, each showing unique properties. The origin of this variability, at least for a fraction of long GRBs, may be the result of an unsteady central engine. It is thus important to study the effects that an episodic central engine has on the jet propagation and, eventually, on the prompt emission within the collapsar scenario. Thus, in this study we follow the interaction of pulsed outflows with their progenitor stars with hydrodynamic numerical simulations in both two and three dimensions. We show that the propagation of unsteady jets is affected bymore » the interaction with the progenitor material well after the break-out time, especially for jets with long quiescent times comparable to or larger than a second. We also show that this interaction can lead to an asymmetric behavior in which pulse durations and quiescent periods are systematically different. After the pulsed jets drill through the progenitor and the interstellar medium, we find that, on average, the quiescent epochs last longer than the pulses (even in simulations with symmetrical active and quiescent engine times). This could explain the asymmetry detected in the light curves of long quiescent time GRBs.« less
Collaborative Writing in Engineering: Perspectives from Research and Implications for Undergraduate Education

ERIC Educational Resources Information Center

Gimenez, J.; Thondhlana, J.

2012-01-01

In engineering, like in many other disciplines, collaborative writing (CW) has been identified as a central practice in both the academy and industry. A number of studies have shown that both students and professionals in this field write most discipline-specific genres collaboratively. Despite its centrality, CW in engineering is still an…
Taking emotion seriously: meeting students where they are.

PubMed

Sunderland, Mary E

2014-03-01

Emotions are often portrayed as subjective judgments that pose a threat to rationality and morality, but there is a growing literature across many disciplines that emphasizes the centrality of emotion to moral reasoning. For engineers, however, being rational usually means sequestering emotions that might bias analyses-good reasoning is tied to quantitative data, math, and science. This paper brings a new pedagogical perspective that strengthens the case for incorporating emotions into engineering ethics. Building on the widely established success of active and collaborative learning environments, in particular the problem-based learning (PBL) philosophy and methodology, the paper articulates new strategies for incorporating emotion into engineering ethics education. An ethics education pilot study is analyzed to explore how PBL can engage students' emotions. Evidence suggests that PBL empowers students to cultivate value for engineering ethics and social responsibility, and in doing so, redefine the societal role of the engineer. Taking students' emotions seriously in engineering ethics offers an effective strategy to meaningfully engage students in ethical learning.
A NARROW SHORT-DURATION GRB JET FROM A WIDE CENTRAL ENGINE

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

Duffell, Paul C.; Quataert, Eliot; MacFadyen, Andrew I., E-mail: duffell@berkeley.edu

2015-11-01

We use two-dimensional relativistic hydrodynamic numerical calculations to show that highly collimated relativistic jets can be produced in neutron star merger models of short-duration gamma-ray bursts (GRBs) without the need for a highly directed engine or a large net magnetic flux. Even a hydrodynamic engine generating a very wide sustained outflow on small scales can, in principle, produce a highly collimated relativistic jet, facilitated by a dense surrounding medium that provides a cocoon surrounding the jet core. An oblate geometry to the surrounding gas significantly enhances the collimation process. Previous numerical simulations have shown that the merger of two neutronmore » stars produces an oblate, expanding cloud of dynamical ejecta. We show that this gas can efficiently collimate the central engine power much like the surrounding star does in long-duration GRB models. For typical short-duration GRB central engine parameters, we find jets with opening angles of an order of 10° in which a large fraction of the total outflow power of the central engine resides in highly relativistic material. These results predict large differences in the opening angles of outflows from binary neutron star mergers versus neutron star–black hole mergers.« less
The role of hardware in learning engineering fundamentals: An empirical study of engineering design and product analysis activity

NASA Astrophysics Data System (ADS)

Brereton, Margot Felicity

A series of short engineering exercises and design projects was created to help students learn to apply abstract knowledge to physical experiences with hardware. The exercises involved designing machines from kits of materials and dissecting and analyzing familiar household products. Students worked in teams. During the activities students brought their knowledge of engineering fundamentals to bear. Videotape analysis was used to identify and characterize the ways in which hardware contributed to learning fundamental concepts. Structural and qualitative analyses of videotaped activities were undertaken. Structural analysis involved counting the references to theory and hardware and the extent of interleaving of references in activity. The analysis found that there was much more discussion linking fundamental concepts to hardware in some activities than in others. The analysis showed that the interleaving of references to theory and hardware in activity is observable and quantifiable. Qualitative analysis was used to investigate the dialog linking concepts and hardware. Students were found to advance their designs and their understanding of engineering fundamentals through a negotiation process in which they pitted abstract concepts against hardware behavior. Through this process students sorted out theoretical assumptions and causal relations. In addition they discovered design assumptions, functional connections and physical embodiments of abstract concepts in hardware, developing a repertoire of familiar hardware components and machines. Hardware was found to be integral to learning, affecting the course of inquiry and the dynamics of group interaction. Several case studies are presented to illustrate the processes at work. The research illustrates the importance of working across the boundary between abstractions and experiences with hardware in order to learn engineering and physical sciences. The research findings are: (a) the negotiation process by which students discover fundamental concepts in hardware (and three central causes of negotiation breakdown); (b) a characterization of the ways that material systems contribute to learning activities, (the seven roles of hardware in learning); (c) the characteristics of activities that support discovering fundamental concepts in hardware (plus several engineering exercises); (d) a research methodology to examine how students learn in practice.
Computer networks for remote laboratories in physics and engineering

NASA Technical Reports Server (NTRS)

Starks, Scott; Elizandro, David; Leiner, Barry M.; Wiskerchen, Michael

1988-01-01

This paper addresses a relatively new approach to scientific research, telescience, which is the conduct of scientific operations in locations remote from the site of central experimental activity. A testbed based on the concepts of telescience is being developed to ultimately enable scientific researchers on earth to conduct experiments onboard the Space Station. This system along with background materials are discussed.
Transcript abundance on its own cannot be used to infer fluxes in central metabolism

DOE PAGES

Schwender, Jorg; Konig, Christina; Klapperstuck, Matthias; ...

2014-11-28

An attempt has been made to define the extent to which metabolic flux in central plant metabolism is reflected by changes in the transcriptome and metabolome, based on an analysis of in vitro cultured immature embryos of two oilseed rape (Brassica napus) accessions which contrast for seed lipid accumulation. Metabolic flux analysis (MFA) was used to constrain a flux balance metabolic model which included 671 biochemical and transport reactions within the central metabolism. This highly confident flux information was eventually used for comparative analysis of flux vs. transcript (metabolite). Metabolite profiling succeeded in identifying 79 intermediates within the central metabolism,more » some of which differed quantitatively between the two accessions and displayed a significant shift corresponding to flux. An RNA-Seq based transcriptome analysis revealed a large number of genes which were differentially transcribed in the two accessions, including some enzymes/proteins active in major metabolic pathways. With a few exceptions, differential activity in the major pathways (glycolysis, TCA cycle, amino acid, and fatty acid synthesis) was not reflected in contrasting abundances of the relevant transcripts. The conclusion was that transcript abundance on its own cannot be used to infer metabolic activity/fluxes in central plant metabolism. Lastly, this limitation needs to be borne in mind in evaluating transcriptome data and designing metabolic engineering experiments.« less
Managing the three-rivers headwater region, china: from ecological engineering to social engineering.

PubMed

Fang, Yiping

2013-09-01

The three-rivers headwater region (THRHR) of Qinghai province, China plays a key role as source of fresh water and ecosystem services for central and eastern China. Global warming and human activities in the THRHR have threatened the ecosystem since the 1980s. Therefore, the Chinese government has included managing of the THRHR in the national strategy since 2003. The State Integrated Test and Demonstration Region of the THRHR highlights the connection with social engineering (focus on improving people's livelihood and well-being) in managing nature reserves. Based on this program, this perspective attempts a holistic analysis of the strategic role of the THRHR, requirements for change, indices of change, and approaches to change. Long-term success of managing nature reserves requires effective combination of ecological conservation, economic development, and social progress. Thus, the philosophy of social engineering should be employed as a strategy to manage the THRHR.
Local Technical Resources for Development of Seismic Monitoring in Caucasus and Central Asia - GMSys2009 Data Acquisition System

NASA Astrophysics Data System (ADS)

Chkhaidze, D.; Basilaia, G.; Elashvili, M.; Shishlov, D.; Bidzinashvili, G.

2012-12-01

Caucasus and Central Asia represents regions of high seismic activity, composing a significant part of Alpine-Himalayan continental collision zone. Natural catastrophic events cause significant damage to the infrastructure worldwide, among these approximately ninety percent of the annual loss is due to earthquakes. Monitoring of Seismic Activity in these regions and adequate assessment of Seismic Hazards represents indispensible condition for safe and stable development. Existence of critical engineering constructions in the Caucasus and Central Asia such as oil and gas pipelines, high dams and nuclear power plants dramatically raises risks associated with natural hazards and eliminates necessity of proper monitoring systems. Our initial efforts were focused on areas that we are most familiar; the geophysical community in the greater Caucuses and Central Asia experiencing many of the same problems with the monitoring equipment. As a result, during the past years GMSys2009 was develop at the Institute of Earth Sciences of Ilia State University. Equipment represents a cost-effective, multifunctional Geophysical Data Acquisition System (DAS) to monitor seismic waves propagating in the earth and related geophysical parameters. Equipment best fits local requirements concerning power management, environmental protection and functionality, the same time competing commercial units available on the market. During past several years more than 30 units were assembled and what is most important installed in Georgia, Armenia, Azerbaijan and Tajikistan. GMSys2009 utilizes standard MiniSEED data format and data transmission protocols, making it possible online waveform data sharing between the neighboring Countries in the region and international community. All the mentioned installations were technically supported by the group of engineers from the Institute of Earth Sciences, on site trainings for local personnel in Armenia, Azerbaijan and Tajikistan was provided creating a good basis for successful functioning of the equipment.

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

Schwender, Jorg; Konig, Christina; Klapperstuck, Matthias

An attempt has been made to define the extent to which metabolic flux in central plant metabolism is reflected by changes in the transcriptome and metabolome, based on an analysis of in vitro cultured immature embryos of two oilseed rape (Brassica napus) accessions which contrast for seed lipid accumulation. Metabolic flux analysis (MFA) was used to constrain a flux balance metabolic model which included 671 biochemical and transport reactions within the central metabolism. This highly confident flux information was eventually used for comparative analysis of flux vs. transcript (metabolite). Metabolite profiling succeeded in identifying 79 intermediates within the central metabolism,more » some of which differed quantitatively between the two accessions and displayed a significant shift corresponding to flux. An RNA-Seq based transcriptome analysis revealed a large number of genes which were differentially transcribed in the two accessions, including some enzymes/proteins active in major metabolic pathways. With a few exceptions, differential activity in the major pathways (glycolysis, TCA cycle, amino acid, and fatty acid synthesis) was not reflected in contrasting abundances of the relevant transcripts. The conclusion was that transcript abundance on its own cannot be used to infer metabolic activity/fluxes in central plant metabolism. Lastly, this limitation needs to be borne in mind in evaluating transcriptome data and designing metabolic engineering experiments.« less
Multivariate assessment of the central-cardiorespiratory network structure in neuropathological disease.

PubMed

Schulz, Steffen; Haueisen, Jens; Bär, Karl-Juergen; Voss, Andreas

2018-06-22

The new interdisciplinary field of network physiology is getting more and more into the focus of interest in medicine. The autonomic nervous system (ANS) dysfunction is well described in schizophrenia (SZO). However, the linear and nonlinear coupling between the ANS and central nervous system (CNS) is only partly addressed until now. This coupling can be assumed as a feedback-feedforward network, reacting with flexible and adaptive responses to internal and external factors. Approach: For the first time, in this study, we investigated linear and nonlinear short-term central-cardiorespiratory couplings of 17 patients suffering from paranoid schizophrenia (SZO) in comparison to 17 age-gender matched healthy subjects (CON) analyzing heart rate (HR), respiration (RESP) and the power of frontal EEG activity (PEEG). The objective is to determine how the different regulatory aspects of the CNS-ANS compose the central-cardiorespiratory network (CCRN). To quantify these couplings within the CCRN the normalized short time partial directed coherence (NSTPDC) and the new multivariate high-resolution joint symbolic dynamics (mHRJSD) were applied. Main results: We found that the CCRN in SZO is characterized as a bidirectional one, with stronger central driving mechanisms (PEEG→HR) towards HR regulation than vice versa, and with stronger respiratory influence (RESP→PEEG) on central activity than vice versa. This suggests that the central-cardiorespiratory process (closed-loop) is mainly focusing on adapting the HR via the sinoatrial node than focusing on respiratory regulation. On the other side, the feedback-loop from ANS to CNS is strongly dominated via respiratory activity. Significance: We could demonstrate a considerably significantly different central-cardiorespiratory network structure in schizophrenia with strong central influence on the cardiac system and a strong respiratory influence on the central nervous system. Moreover, this study provides a more in-depth understanding of the interplay of the central and autonomic regulatory network in healthy subjects and schizophrenic patients. . © 2018 Institute of Physics and Engineering in Medicine.
Artificial membrane-binding proteins stimulate oxygenation of stem cells during engineering of large cartilage tissue

NASA Astrophysics Data System (ADS)

Armstrong, James P. K.; Shakur, Rameen; Horne, Joseph P.; Dickinson, Sally C.; Armstrong, Craig T.; Lau, Katherine; Kadiwala, Juned; Lowe, Robert; Seddon, Annela; Mann, Stephen; Anderson, J. L. Ross; Perriman, Adam W.; Hollander, Anthony P.

2015-06-01

Restricted oxygen diffusion can result in central cell necrosis in engineered tissue, a problem that is exacerbated when engineering large tissue constructs for clinical application. Here we show that pre-treating human mesenchymal stem cells (hMSCs) with synthetic membrane-active myoglobin-polymer-surfactant complexes can provide a reservoir of oxygen capable of alleviating necrosis at the centre of hyaline cartilage. This is achieved through the development of a new cell functionalization methodology based on polymer-surfactant conjugation, which allows the delivery of functional proteins to the hMSC membrane. This new approach circumvents the need for cell surface engineering using protein chimerization or genetic transfection, and we demonstrate that the surface-modified hMSCs retain their ability to proliferate and to undergo multilineage differentiation. The functionalization technology is facile, versatile and non-disruptive, and in addition to tissue oxygenation, it should have far-reaching application in a host of tissue engineering and cell-based therapies.
Development of a forestry government agency enterprise GIS system: a disconnected editing approach

NASA Astrophysics Data System (ADS)

Zhu, Jin; Barber, Brad L.

2008-10-01

The Texas Forest Service (TFS) has developed a geographic information system (GIS) for use by agency personnel in central Texas for managing oak wilt suppression and other landowner assistance programs. This Enterprise GIS system was designed to support multiple concurrent users accessing shared information resources. The disconnected editing approach was adopted in this system to avoid the overhead of maintaining an active connection between TFS central Texas field offices and headquarters since most field offices are operating with commercially provided Internet service. The GIS system entails maintaining a personal geodatabase on each local field office computer. Spatial data from the field is periodically up-loaded into a central master geodatabase stored in a Microsoft SQL Server at the TFS headquarters in College Station through the ESRI Spatial Database Engine (SDE). This GIS allows users to work off-line when editing data and requires connecting to the central geodatabase only when needed.
Central-engine-powered Bright X-Ray Flares in Short Gamma-Ray Bursts: A Hint of a Black Hole–Neutron Star Merger?

NASA Astrophysics Data System (ADS)

Mu, Hui-Jun; Gu, Wei-Min; Mao, Jirong; Hou, Shu-Jin; Lin, Da-Bin; Liu, Tong

2018-05-01

Short gamma-ray bursts may originate from the merger of a double neutron star (NS) or the merger of a black hole (BH) and an NS. We propose that the bright X-ray flare related to the central engine reactivity may indicate a BH–NS merger, since such a merger can provide more fallback materials and therefore a more massive accretion disk than the NS–NS merger. Based on the 49 observed short bursts with the Swift/X-ray Telescope follow-up observations, we find that three bursts have bright X-ray flares, among which three flares from two bursts are probably related to the central engine reactivity. We argue that these two bursts may originate from the BH–NS merger rather than the NS–NS merger. Our suggested link between the central-engine-powered bright X-ray flare and the BH–NS merger event can be checked by future gravitational wave detections from advanced LIGO and Virgo.
THE BLACK HOLE CENTRAL ENGINE FOR ULTRA-LONG GAMMA-RAY BURST 111209A AND ITS ASSOCIATED SUPERNOVA 2011KL

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

Gao, He; You, Zhi-Qiang; Lei, Wei-Hua

Recently, the first association between an ultra-long gamma-ray burst (GRB) and a supernova was reported, i.e., GRB 111209A/SN 2011kl, enabling us to investigate the physics of central engines or even progenitors for ultra-long GRBs. In this paper, we inspect the broadband data of GRB 111209A/SN 2011kl. The late-time X-ray light curve exhibits a GRB 121027A-like fallback bump, suggesting a black hole (BH) central engine. We thus propose a collapsar model with fallback accretion for GRB 111209A/SN 2011kl. The required model parameters, such as the total mass and radius of the progenitor star, suggest that the progenitor of GRB 111209A ismore » more likely a Wolf–Rayet star instead of a blue supergiant, and the central engine of this ultra-long burst is a BH. The implications of our results are discussed.« less
The Stanford how things work project

NASA Technical Reports Server (NTRS)

Fikes, Richard; Gruber, Tom; Iwasaki, Yumi

1994-01-01

We provide an overview of the Stanford How Things Work (HTW) project, an ongoing integrated collection of research activities in the Knowledge Systems Laboratory at Stanford University. The project is developing technology for representing knowledge about engineered devices in a form that enables the knowledge to be used in multiple systems for multiple reasoning tasks and reasoning methods that enable the represented knowledge to be effectively applied to the performance of the core engineering task of simulating and analyzing device behavior. The central new capabilities currently being developed in the project are automated assistance with model formulation and with verification that a design for an electro-mechanical device satisfies its functional specification.
Proceedings of the 21st Project Integration Meeting

NASA Technical Reports Server (NTRS)

1983-01-01

Progress made by the Flat Plate Solar Array Project during the period April 1982 to January 1983 is described. Reports on polysilicon refining, thin film solar cell and module technology development, central station electric utility activities, silicon sheet growth and characteristics, advanced photovoltaic materials, cell and processes research, module technology, environmental isolation, engineering sciences, module performance and failure analysis and project analysis and integration are included.
How long does a burst burst?

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

Zhang, Bin-Bin; Connaughton, Valerie; Briggs, Michael S.

2014-05-20

Several gamma-ray bursts (GRBs) last much longer (∼hours) in γ-rays than typical long GRBs (∼minutes), and it has recently been proposed that these 'ultra-long GRBs' may form a distinct population, probably with a different (e.g., blue supergiant) progenitor than typical GRBs. However, Swift observations suggest that many GRBs have extended central engine activities manifested as flares and internal plateaus in X-rays. We perform a comprehensive study on a large sample of Swift GRBs with X-Ray Telescope observations to investigate GRB central engine activity duration and to determine whether ultra-long GRBs are unusual events. We define burst duration t {sub burst}more » based on both γ-ray and X-ray light curves rather than using γ-ray observations alone. We find that t {sub burst} can be reliably measured in 343 GRBs. Within this 'good' sample, 21.9% GRBs have t {sub burst} ≳ 10{sup 3} s and 11.5% GRBs have t {sub burst} ≳ 10{sup 4} s. There is an apparent bimodal distribution of t {sub burst} in this sample. However, when we consider an 'undetermined' sample (304 GRBs) with t {sub burst} possibly falling in the gap between GRB duration T {sub 90} and the first X-ray observational time, as well as a selection effect against t {sub burst} falling into the first Swift orbital 'dead zone' due to observation constraints, the intrinsic underlying t {sub burst} distribution is consistent with being a single component distribution. We found that the existing evidence for a separate ultra-long GRB population is inconclusive, and further multi-wavelength observations are needed to draw a firmer conclusion. We also discuss the theoretical implications of our results. In particular, the central engine activity duration of GRBs is generally much longer than the γ-ray T {sub 90} duration and it does not even correlate with T {sub 90}. It would be premature to make a direct connection between T {sub 90} and the size of the progenitor star.« less
An infrared flash contemporaneous with the gamma-rays of GRB 041219a.

PubMed

Blake, C H; Bloom, J S; Starr, D L; Falco, E E; Skrutskie, M; Fenimore, E E; Duchêne, G; Szentgyorgyi, A; Hornstein, S; Prochaska, J X; McCabe, C; Ghez, A; Konopacky, Q; Stapelfeldt, K; Hurley, K; Campbell, R; Kassis, M; Chaffee, F; Gehrels, N; Barthelmy, S; Cummings, J R; Hullinger, D; Krimm, H A; Markwardt, C B; Palmer, D; Parsons, A; McLean, K; Tueller, J

2005-05-12

The explosion that results in a cosmic gamma-ray burst (GRB) is thought to produce emission from two physical processes: the central engine gives rise to the high-energy emission of the burst through internal shocking, and the subsequent interaction of the flow with the external environment produces long-wavelength afterglows. Although observations of afterglows continue to refine our understanding of GRB progenitors and relativistic shocks, gamma-ray observations alone have not yielded a clear picture of the origin of the prompt emission nor details of the central engine. Only one concurrent visible-light transient has been found and it was associated with emission from an external shock. Here we report the discovery of infrared emission contemporaneous with a GRB, beginning 7.2 minutes after the onset of GRB 041219a (ref. 8). We acquired 21 images during the active phase of the burst, yielding early multi-colour observations. Our analysis of the initial infrared pulse suggests an origin consistent with internal shocks.
Radio Source Morphology: 'nature or nuture'?

NASA Astrophysics Data System (ADS)

Banfield, Julie; Emonts, Bjorn; O'Sullivan, Shane

2012-10-01

Radio sources, emanating from supermassive black-holes in the centres of active galaxies, display a large variety of morphological properties. It is a long-standing debate to what extent the differences between various types of radio sources are due to intrinsic properties of the central engine (`nature') or due to the properties of the interstellar medium that surrounds the central engine and host galaxy (`nurture'). Settling this `nature vs. nurture' debate for nearby radio galaxies, which can be studied in great detail, is vital for understanding the properties and evolution of radio galaxies throughout the Universe. We propose to observe the radio galaxy NGC 612 where previous observations have detected the presence of a large-scale HI bridge between the host galaxy and a nearby galaxy NGC 619. We request a total of 13 hrs in the 750m array-configuration to determine whether or not the 100 kpc-scale radio source morphology is directly related to the intergalactic distribution of neutral hydrogen gas.
Standardized Fault-Tolerant Sensing Nodes for an Intelligent Turbine Engine Control System (Preprint)

DTIC Science & Technology

2013-05-01

representation of a centralized control system on a turbine engine. All actuators and sensors are point-to-point cabled to the controller ( FADEC ) which...electronics themselves. Figure 1: Centralized Control System Each function resides within the FADEC and uses Unique Point-to-Point Analog...distributed control system on the same turbine engine. The actuators and sensors interface to Smart Nodes which, in turn communicate to the FADEC via
Radiative transfer calculations of ultra-relativistic shock breakout in circumstellar medium: Dependence on the central engine activity

NASA Astrophysics Data System (ADS)

Ohtani, Yukari; Suzuki, Akihiro; Shigeyama, Toshikazu

2015-08-01

Core collapse supernovae radiate bright X-ray or UV flashes imediately after their explosion, because shock waves emerge on the surfaces of the progenitors. Due to their short duration, a very small number of such events (so called shock breakouts) have been observed, and the maximum shock velocities are likely to be significantly smaller than the speed of light. In principle, we can consider the shocks with ultra-relativistic velocities breakout stellar surfaces and generate gamma-ray photons. A recently popular theory of gamma-ray bursts argues that the thermal radiation produced in the jet may play important roles in the prompt emission. Therefore, for understanding of the relation between jets and the central engine, studying properties of breakouts in the relativistic limit will be interesting. To obtain some information concerning the temporal evolution of the photospheric emission from jets, we make a radiative transfer calculation of ultra-relativistic shock breakout in circumstellar medium by using a Monte Carlo method. We use a self-similar solution constructed by Blandford & McKee (1976), in which the shock Lorentz factor is assumed to follow a simple power law relation determined by the central engine activity. By comparing the calculation results of the accelerating shock and the decelerating shock, we find that influence of the beaming effect and the scattering angular distribution cause two apparent differences in light curves and temporal spectral evolution. One is that the ratio of the time between the onset and the peak to the duration is much smaller in light curves of decelerating shocks. The other one is that the spectral shape does not significantly change with time if the shock accelerates, otherwise the first half of the emerging photons contains much more high energy photons (above 1 MeV) than the second half.
Pondermotive acceleration of charged particles along the relativistic jets of an accreting blackhole

NASA Astrophysics Data System (ADS)

Ebisuzaki, T.; Tajima, T.

2014-05-01

Accreting blackholes such as miniquasars and active galactic nuclei can contribute to the highest energy components of intra- (˜1015 eV) galactic and extra-galactic components (˜1020 eV) of cosmic rays. Alfven wave pulses which are excited in the accretion disk around blackholes propagate in relativistic jets. Because of their highly non-linear nature of the waves, charged particles (protons, ions, and electrons) can be accelerated to high energies in relativistic jets in accreting blackhole systems, the central engine of miniquasars and active galactic nuclei.
Detection of 183 GHz H2O megamaser emission towards NGC 4945

NASA Astrophysics Data System (ADS)

Humphreys, E. M. L.; Vlemmings, W. H. T.; Impellizzeri, C. M. V.; Galametz, M.; Olberg, M.; Conway, J. E.; Belitsky, V.; De Breuck, C.

2016-08-01

Aims: The aim of this work is to search Seyfert 2 galaxy NGC 4945, a well-known 22 GHz water megamaser galaxy, for H2O (mega)maser emission at 183 GHz. Methods: We used APEX SEPIA Band 5 (an ALMA Band 5 receiver on the APEX telescope) to perform the observations. Results: We detected 183 GHz H2O maser emission towards NGC 4945 with a peak flux density of ~3 Jy near the galactic systemic velocity. The emission spans a velocity range of several hundred km s-1. We estimate an isotropic luminosity of >1000 L⊙, classifying the emission as a megamaser. A comparison of the 183 GHz spectrum with that observed at 22 GHz suggests that 183 GHz emission also arises from the active galactic nucleus (AGN) central engine. If the 183 GHz emission originates from the circumnuclear disk, then we estimate that a redshifted feature at 1084 km s-1 in the spectrum should arise from a distance of 0.022 pc from the supermassive black hole (1.6 × 105 Schwarzschild radii), I.e. closer than the water maser emission previously detected at 22 GHz. This is only the second time 183 GHz maser emission has been detected towards an AGN central engine (the other galaxy being NGC 3079). It is also the strongest extragalactic millimetre/submillimetre water maser detected to date. Conclusions: Strong millimetre 183 GHz H2O maser emission has now been shown to occur in an external galaxy. For NGC 4945, we believe that the maser emission arises, or is dominated by, emission from the AGN central engine. Emission at higher velocity, I.e. for a Keplerian disk closer to the black hole, has been detected at 183 GHz compared with that for the 22 GHz megamaser. This indicates that millimetre/submillimetre H2O masers can indeed be useful for tracing out more of AGN central engine structures and dynamics than previously probed. Future observations using ALMA Band 5 should unequivocally determine the origin of the emission in this and other galaxies.
24. Photocopy of engineering drawing, May, 1941 (original drawing located ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

24. Photocopy of engineering drawing, May, 1941 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering vault). ENGINE TEST CELL BUILDING. ELEVATIONS, CENTRAL PORTION AND TEST CELLS 1-4. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA
26. Photocopy of engineering drawing, May, 1941 (original drawing located ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

26. Photocopy of engineering drawing, May, 1941 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering vault). ENGINE TEST CELL BUILDING. CROSS-SECTION, CENTRAL PORTION AND TEST CELLS 1-4. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA
29. Photocopy of engineering drawing, May, 1941 (original drawing located ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

29. Photocopy of engineering drawing, May, 1941 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering vault). ENGINE TEST CELL BUILDING. 19508 RENOVATION OF FIRST FLOOR, CENTRAL PORTION. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA
Lyceum: A Multi-Protocol Digital Library Gateway

NASA Technical Reports Server (NTRS)

Maa, Ming-Hokng; Nelson, Michael L.; Esler, Sandra L.

1997-01-01

Lyceum is a prototype scalable query gateway that provides a logically central interface to multi-protocol and physically distributed, digital libraries of scientific and technical information. Lyceum processes queries to multiple syntactically distinct search engines used by various distributed information servers from a single logically central interface without modification of the remote search engines. A working prototype (http://www.larc.nasa.gov/lyceum/) demonstrates the capabilities, potentials, and advantages of this type of meta-search engine by providing access to over 50 servers covering over 20 disciplines.
Blending Education and Polymer Science: Semi Automated Creation of a Thermodynamic Property Database.

PubMed

Tchoua, Roselyne B; Qin, Jian; Audus, Debra J; Chard, Kyle; Foster, Ian T; de Pablo, Juan

2016-09-13

Structured databases of chemical and physical properties play a central role in the everyday research activities of scientists and engineers. In materials science, researchers and engineers turn to these databases to quickly query, compare, and aggregate various properties, thereby allowing for the development or application of new materials. The vast majority of these databases have been generated manually, through decades of labor-intensive harvesting of information from the literature; yet, while there are many examples of commonly used databases, a significant number of important properties remain locked within the tables, figures, and text of publications. The question addressed in our work is whether, and to what extent, the process of data collection can be automated. Students of the physical sciences and engineering are often confronted with the challenge of finding and applying property data from the literature, and a central aspect of their education is to develop the critical skills needed to identify such data and discern their meaning or validity. To address shortcomings associated with automated information extraction, while simultaneously preparing the next generation of scientists for their future endeavors, we developed a novel course-based approach in which students develop skills in polymer chemistry and physics and apply their knowledge by assisting with the semi-automated creation of a thermodynamic property database.

Blending Education and Polymer Science: Semiautomated Creation of a Thermodynamic Property Database

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

Tchoua, Roselyne B.; Qin, Jian; Audus, Debra J.

Structured databases of chemical and physical properties play a central role in the everyday research activities of scientists and engineers. In materials science, researchers and engineers turn to these databases to quickly query, compare, and aggregate various properties, thereby allowing for the development or application of new materials. The vast majority of these databases have been generated manually, through decades of labor-intensive harvesting of information from the literature, yet while there are many examples of commonly used databases, a significant number of important properties remain locked within the tables, figures, and text of publications. The question addressed in our workmore » is whether and to what extent the process of data collection can be automated. Students of the physical sciences and engineering are often confronted with the challenge of finding and applying property data from the literature, and a central aspect of their education is to develop the critical skills needed to identify such data and discern their meaning or validity. To address shortcomings associated with automated information extraction while simultaneously preparing the next generation of scientists for their future endeavors, we developed a novel course-based approach in which students develop skills in polymer chemistry and physics and apply their knowledge by assisting with the semiautomated creation of a thermodynamic property database.« less
Centralized remote structural monitoring and management of real-time data

NASA Astrophysics Data System (ADS)

Han, Liting; Newhook, John P.; Mufti, Aftab A.

2004-07-01

Structural health monitoring (SHM) activities in civil engineering are increasing at a rapid pace in both research and field applications. This paper addresses the specific issue of incorporating internet technology into a structural health monitoring program. The issue of data volume versus communication speed is discussed along with a practical solution employed by ISIS Canada. The approach is illustrated through reference to several current case studies which include two bridges and a statue. It is seen that although the specifics of the projects and monitoring needs are different, the manner in which on-line monitoring can be conducted is very similar and easily allows for centralized monitoring. A general framework for website construction integrating sensing data and web camera options are presented. Issues related to simple real-time performance indices versus more comprehensive complex data analysis are discussed. Examples of on-line websites which allow visualization of new and historic data are presented. The paper also discusses future activities and research needs related to centralized remote structural monitoring and management of real-time data.
International GPS Service 2001 - 2002 Technical Reports

NASA Technical Reports Server (NTRS)

Gowey, Ken (Editor); Neilan, Ruth (Editor); Moore, Angelyn (Editor)

2004-01-01

Applications of the Global Positioning System (GPS) to Earth Science are numerous. The International GPS Service (IGS), a federation of government agencies and universities, plays an increasingly critical role in support of GPS-related research and engineering activities. Contributions from the IGS Governing Board and Central Bureau, analysis and data centers, station operators, and others constitute the 2001 / 2002 Technical Reports. Hard copies of each volume can be obtained by contacting the IGS Central Bureau at the Jet Propulsion Laboratory. This report is published in black and white. To view graphs or plots that use color to represent data trends or information, please refer to the online PDF version at http://igscb.jpl.nasa.gov/overview/pubs.html.
Ion Engine and Hall Thruster Development at the NASA Glenn Research Center

NASA Technical Reports Server (NTRS)

Domonkos, Matthew T.; Patterson, Michael J.; Jankovsky, Robert S.

2002-01-01

NASA's Glenn Research Center has been selected to lead development of NASA's Evolutionary Xenon Thruster (NEXT) system. The central feature of the NEXT system is an electric propulsion thruster (EPT) that inherits the knowledge gained through the NSTAR thruster that successfully propelled Deep Space 1 to asteroid Braille and comet Borrelly, while significantly increasing the thruster power level and making improvements in performance parameters associated with NSTAR. The EPT concept under development has a 40 cm beam diameter, twice the effective area of the Deep-Space 1 thruster, while maintaining a relatively-small volume. It incorporates mechanical features and operating conditions to maximize the design heritage established by the flight NSTAR 30 cm engine, while incorporating new technology where warranted to extend the power and throughput capability. The NASA Hall thruster program currently supports a number of tasks related to high power thruster development for a number of customers including the Energetics Program (formerly called the Space-based Program), the Space Solar Power Program, and the In-space Propulsion Program. In program year 2002, two tasks were central to the NASA Hall thruster program: 1.) the development of a laboratory Hall thruster capable of providing high thrust at high power; 2.) investigations into operation of Hall thrusters at high specific impulse. In addition to these two primary thruster development activities, there are a number of other on-going activities supported by the NASA Hall thruster program, These additional activities are related to issues such as thruster lifetime and spacecraft integration.
18. Photocopy of engineering drawing, May, 1941 (original drawing located ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

18. Photocopy of engineering drawing, May, 1941 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering vault). ENGINE TEST CELL BUILDING. FIRST FLOOR PLAN, CENTRAL PORTION AND TEST CELLS 1-4. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA
22. Photocopy of engineering drawing, May, 1941 (original drawing located ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

22. Photocopy of engineering drawing, May, 1941 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering vault). ENGINE TEST CELL BUILDING. THIRD FLOOR AND ROOF PLAN, CENTRAL PORTION AND TEST CELLS 1-4. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA
16. Photocopy of engineering drawing, May, 1941 (original drawing located ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. Photocopy of engineering drawing, May, 1941 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering vault). ENGINE TEST CELL BUILDING. BASEMENT FLOOR PLAN, CENTRAL PORTION AND TEST CELLS 1-4. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA
20. Photocopy of engineering drawing, May, 1941 (original drawing located ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

20. Photocopy of engineering drawing, May, 1941 (original drawing located at Fairchild Air Force Base, Civil Engineering Building, Civil Engineering vault). ENGINE TEST CELL BUILDING. SECOND FLOOR PLAN, CENTRAL PORTION AND TEST CELLS 1-4. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA
Solar thermal power systems point-focusing thermal and electric applications projects. Volume 1: Executive summary

NASA Technical Reports Server (NTRS)

Marriott, A.

1980-01-01

The activities of the Point-Focusing Thermal and Electric Applications (PETEA) project for the fiscal year 1979 are summarized. The main thrust of the PFTEA Project, the small community solar thermal power experiment, was completed. Concept definition studies included a small central receiver approach, a point-focusing distributed receiver system with central power generation, and a point-focusing distributed receiver concept with distributed power generation. The first experiment in the Isolated Application Series was initiated. Planning for the third engineering experiment series, which addresses the industrial market sector, was also initiated. In addition to the experiment-related activities, several contracts to industry were let and studies were conducted to explore the market potential for point-focusing distributed receiver (PFDR) systems. System analysis studies were completed that looked at PFDR technology relative to other small power system technology candidates for the utility market sector.
Systems engineering in the Large Synoptic Survey Telescope project: an application of model based systems engineering

NASA Astrophysics Data System (ADS)

Claver, C. F.; Selvy, Brian M.; Angeli, George; Delgado, Francisco; Dubois-Felsmann, Gregory; Hascall, Patrick; Lotz, Paul; Marshall, Stuart; Schumacher, German; Sebag, Jacques

2014-08-01

The Large Synoptic Survey Telescope project was an early adopter of SysML and Model Based Systems Engineering practices. The LSST project began using MBSE for requirements engineering beginning in 2006 shortly after the initial release of the first SysML standard. Out of this early work the LSST's MBSE effort has grown to include system requirements, operational use cases, physical system definition, interfaces, and system states along with behavior sequences and activities. In this paper we describe our approach and methodology for cross-linking these system elements over the three classical systems engineering domains - requirement, functional and physical - into the LSST System Architecture model. We also show how this model is used as the central element to the overall project systems engineering effort. More recently we have begun to use the cross-linked modeled system architecture to develop and plan the system verification and test process. In presenting this work we also describe "lessons learned" from several missteps the project has had with MBSE. Lastly, we conclude by summarizing the overall status of the LSST's System Architecture model and our plans for the future as the LSST heads toward construction.
An Engineering Research Program for High School Science Teachers: Year Two Changes and Results

ERIC Educational Resources Information Center

DeJong, Brian P.; Yelamarthi, Kumar; Kaya, Tolga

2016-01-01

The research experiences for teachers program at Central Michigan University was initiated to team in-service and pre-service teachers with undergraduate engineering students and engineering faculty, in an engineering research setting. During the six-week program, teachers learn engineering concepts and develop high-school instructional material…
Engine Air Intake Manifold Having Built In Intercooler

DOEpatents

Freese, V, Charles E.

2000-09-12

A turbocharged V type engine can be equipped with an exhaust gas recirculation cooler integrated into the intake manifold, so as to achieve efficiency, cost reductions and space economization improvements. The cooler can take the form of a tube-shell heat exchanger that utilizes a cylindrical chamber in the air intake manifold as the heat exchanger housing. The intake manifold depends into the central space formed by the two banks of cylinders on the V type engine, such that the central space is effectively utilized for containing the manifold and cooler.
ELECTRICAL LINES ARRIVE FROM CENTRAL FACILITIES AREA, SOUTH OF MTR. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

ELECTRICAL LINES ARRIVE FROM CENTRAL FACILITIES AREA, SOUTH OF MTR. EXCAVATION RUBBLE IN FOREGROUND. CONTRACTOR CRAFT SHOPS, CRANES, AND OTHER MATERIALS ON SITE. CAMERA FACES EAST, WITH LITTLE BUTTE AND MIDDLE BUTTE IN DISTANCE. INL NEGATIVE NO. 335. Unknown Photographer, 7/1/1950 - Idaho National Engineering Laboratory, Test Reactor Area, Materials & Engineering Test Reactors, Scoville, Butte County, ID
A relativistic type Ibc supernova without a detected gamma-ray burst.

PubMed

Soderberg, A M; Chakraborti, S; Pignata, G; Chevalier, R A; Chandra, P; Ray, A; Wieringa, M H; Copete, A; Chaplin, V; Connaughton, V; Barthelmy, S D; Bietenholz, M F; Chugai, N; Stritzinger, M D; Hamuy, M; Fransson, C; Fox, O; Levesque, E M; Grindlay, J E; Challis, P; Foley, R J; Kirshner, R P; Milne, P A; Torres, M A P

2010-01-28

Long duration gamma-ray bursts (GRBs) mark the explosive death of some massive stars and are a rare sub-class of type Ibc supernovae. They are distinguished by the production of an energetic and collimated relativistic outflow powered by a central engine (an accreting black hole or neutron star). Observationally, this outflow is manifested in the pulse of gamma-rays and a long-lived radio afterglow. Until now, central-engine-driven supernovae have been discovered exclusively through their gamma-ray emission, yet it is expected that a larger population goes undetected because of limited satellite sensitivity or beaming of the collimated emission away from our line of sight. In this framework, the recovery of undetected GRBs may be possible through radio searches for type Ibc supernovae with relativistic outflows. Here we report the discovery of luminous radio emission from the seemingly ordinary type Ibc SN 2009bb, which requires a substantial relativistic outflow powered by a central engine. A comparison with our radio survey of type Ibc supernovae reveals that the fraction harbouring central engines is low, about one per cent, measured independently from, but consistent with, the inferred rate of nearby GRBs. Independently, a second mildly relativistic supernova has been reported.
Effect of boat noise and angling on lake fish behaviour.

PubMed

Jacobsen, L; Baktoft, H; Jepsen, N; Aarestrup, K; Berg, S; Skov, C

2014-06-01

The effects of disturbances from recreational activities on the swimming speed and habitat use of roach Rutilus rutilus, perch Perca fluviatilis and pike Esox lucius were explored. Disturbances were applied for 4 h as (1) boating in short intervals with a small outboard internal combustion engine or (2) boating in short intervals combined with angling with artificial lures between engine runs. The response of the fish species was evaluated by high-resolution tracking using an automatic acoustic telemetry system and transmitters with sub-minute burst rates. Rutilus rutilus swimming speed was significantly higher during disturbances [both (1) and (2)] with an immediate reaction shortly after the engine started. Perca fluviatilis displayed increased swimming activity during the first hour of disturbance but not during the following hours. Swimming activity of E. lucius was not significantly different between disturbance periods and the same periods on days without disturbance (control). Rutilus rutilus increased their use of the central part of the lake during disturbances, whereas no habitat change was observed in P. fluviatilis and E. lucius. No difference in fish response was detected between the two types of disturbances (boating with and without angling), indicating that boating was the primary source of disturbance. This study highlights species-specific responses to recreational boating and may have implications for management of human recreational activities in lakes. © 2014 The Fisheries Society of the British Isles.
She's an Engineer

NASA Image and Video Library

2016-11-05

Junior Girl Scouts from two locals conceils, Girl Scouts of Central Maryland and Girl Scouts of Nations Capital, participated in She's an Engineer! Girl Scout program on November 3, 2016. They met with female NASA engineers and tested rover models in simulated I&T stations to explore the Engineering Design process.
PREFACE: Astronomy at High Angular Resolution 2011: The central kiloparsec in galactic nuclei

NASA Astrophysics Data System (ADS)

Iserlohe, Christof; Karas, Vladimir; Krips, Melanie; Eckart, Andreas; Britzen, Silke; Fischer, Sebastian

2012-07-01

We are pleased to present the proceedings from the Astronomy at High Angular Resolution 2011: The central kiloparsec in galactic nuclei conference. The conference took place in the Physikzentrum of the Deutsche Physikalische Gesellschaft (DPG), Bad Honnef, Germany, from 28 August to 2 September 2011. It was the second conference of this kind, following the Astronomy at High Angular Resolution conference held in Bad Honnef, three years earlier in 2008. The main objective of the conference was to frame the discussion of the broad range of physical processes that occur in the central 100pc of galactic nuclei. In most cases, this domain is difficult to probe through observations. This is mainly because of the lack of angular resolution, the brightness of the central engine and possible obscurations through dust and gas, which play together in the central regions of host galaxies of galactic nuclei within a broad range of activity. The presence of large amounts of molecular and atomic (both neutral and ionized) gas, dust and central engines with outflows and jets implies that the conditions for star formation in these regions are very special, and probably different from those in the disks of host galaxies. Numerous presentations covering a broad range of topics, both theoretical and experimental, those related to research on Active Galactic Nuclei and on a wide range of observed wavelengths were submitted to the Scientific Organizing Committee. Presentations have been grouped into six sessions: The nuclei of active galaxies The Galactic Center The immediate environment of Super Massive Black Holes The physics of nuclear jets and the interaction of the interstellar medium The central 100pc of the nuclear environment Star formation in that region The editors thank all participants of the AHAR 2011 conference for their enthusiasm and their numerous and vivid contributions to this conference. We would especially like to thank John Hugh Seiradakis from the Aristotle University of Thessaloniki in Greece for giving the dinner talk on the most astounding ancient Antikythera mechanism. We would also like to thank Victor Gomer and the staff of the Physikzentrum of the Deutsche Physikalische Gesellschaft in Bad Honnef where the conference took place. Last but not least we would like to thank all unnamed helpers, without whom the organisation of this conference would not have been possible. Financial support for this conference was granted by the Deutsche Forschungsgemeinschaft (DFG) Sonderforschungsbereich project number SFB 956. We also acknowledge support from the European Community Framework Programme 7, Advanced Radio Astronomy in Europe, grant agreement no. 227290. Christof Iserlohe, Vladimir Karas, Melanie Krips, Andreas Eckart, Silke Britzen and Sebastian Fischer The Editors Conference photograph Conference Group Photo, 1 September 2011 The PDF also contains additional photographs from the conference and the Contents of the Proceedings.
Civil Engineering in Primary Schools

ERIC Educational Resources Information Center

Brown, Martin; Strong, Alan

2010-01-01

For many children of primary school age, an engineer is the man who comes to service the central heating system or who fixes the family car when it breaks down. Most have never met a "real" professional engineer, and have no idea of what is involved in the exciting world of engineering. Most assume that engineers are men. To try to…
Integrated flight/propulsion control system design based on a centralized approach

NASA Technical Reports Server (NTRS)

Garg, Sanjay; Mattern, Duane L.; Bullard, Randy E.

1989-01-01

An integrated flight/propulsion control system design is presented for the piloted longitudinal landing task with a modern, statically unstable, fighter aircraft. A centralized compensator based on the Linear Quadratic Gaussian/Loop Transfer Recovery methodology is first obtained to satisfy the feedback loop performance and robustness specificiations. This high-order centralized compensator is then partitioned into airframe and engine sub-controllers based on modal controllability/observability for the compensator modes. The order of the sub-controllers is then reduced using internally-balanced realization techniques and the sub-controllers are simplified by neglecting the insignificant feedbacks. These sub-controllers have the advantage that they can be implemented as separate controllers on the airframe and the engine while still retaining the important performance and stability characteristics of the full-order centralized compensator. Command prefilters are then designed for the closed-loop system with the simplified sub-controllers to obtain the desired system response to airframe and engine command inputs, and the overall system performance evaluation results are presented.
Accretion and Outflow from a Magnetized, Neutrino Cooled Torus around the Gamma Ray Burst Central Engine

NASA Astrophysics Data System (ADS)

Janiuk, Agnieszka; Moscibrodzka, Monika

Gamma Ray Bursts (GRB) are the extremely energetic transient events, visible from the most distant parts of the Universe. They are most likely powered by accretion on the hyper-Eddington rates that proceeds onto a newly born stellar mass black hole. This central engine gives rise to the most powerful, high Lorentz factor jets that are responsible for energetic gamma ray emission. We investigate the accretion flow evolution in GRB central engine, using the 2D MHD simulations in General Relativity. We compute the structure and evolution of the extremely hot and dense torus accreting onto the fast spinning black hole, which launches the magnetized jets. We calculate the chemical structure of the disk and account for neutrino cooling. Our preliminary runs apply to the short GRB case (remnant torus accreted after NS-NS or NS-BH merger). We estimate the neutrino luminosity of such an event for chosen disk and central BH mass.

Re-Engineering Vocational and Technical Education (VTE) for Sustainable Development in North Central Geo-Political Zone, Nigeria

ERIC Educational Resources Information Center

Sofoluwe, Abayomi Olumade

2013-01-01

The purpose of the study is to re-engineer vocational and technical education for sustainable development in the North Central Geo-Political Zone in Nigeria. The research design adopted was a survey inferential type. Stratified random was used to select 36 schools out of 98 schools while 920 students out of 3680 students were sampled. The data…
Antibodies against viruses: passive and active immunization

PubMed Central

Law, Mansun; Hangartner, Lars

2008-01-01

Summary of recent advances Antibodies, through passive or active immunization, play a central role in prophylaxis against many infectious agents. While neutralization is a primary function of antibodies in protection against most viruses, the relative contribution of Fc-dependent and complement-dependent antiviral activities of antibodies was found to vary between different viruses in recent studies. The multiple hit model explains how antibodies neutralize viruses and recent data on the stoichiometry of antibody neutralization suggest that the organization of viral surface proteins on viruses, in addition to virus size, influences the level of antibody occupancy required for neutralization. These new findings will improve our strategies in therapeutic antibody engineering and rational vaccine design. PMID:18577455
Structure, function, and engineering of enzymes in isoflavonoid biosynthesis.

PubMed

Wang, Xiaoqiang

2011-03-01

Isoflavonoids are a large group of plant natural products and play important roles in plant defense. They also possess valuable health-promoting activities with significant health benefits for animals and humans. The isoflavonoids are identified primarily in leguminous plants and are synthesized through the central phenylpropanoid pathway and the specific isoflavonoid branch pathways in legumes. Structural studies of some key enzymes in the central phenylpropanoid pathway shed light on the early stages of the (iso)flavonoid biosynthetic process. Significant impact has also been made on structural studies of enzymes in the isoflavonoid branch pathways. Structures of isoflavonoid-specific NADPH-dependent reductases revealed how the (iso)flavonoid backbones are modified by reduction reactions and how enzymes specifically recognize isoflavonoids and catalyze stereo-specific reductions. Structural studies of isoflavonoid methyltransferases and glycosyltransferases revealed how isoflavonoids are further decorated with methyl group and sugars in different methylation and glycosylation patterns that determine their bioactivities and functions. In combination with mutagenesis and biochemical studies, the detailed structural information of these enzymes provides a basis for understanding the complex biosynthetic process, enzyme catalytic mechanisms, and substrate specificities. Structure-based homology modeling facilitates the functional characterization of these large groups of biosynthetic enzymes and their homologs. Structure-based enzyme engineering is becoming a new strategy for synthesis of bioactive isoflavonoids and also facilitates plant metabolic engineering towards improvement of quality and production of crop plants.
PHOTOSPHERE EMISSION FROM A HYBRID RELATIVISTIC OUTFLOW WITH ARBITRARY DIMENSIONLESS ENTROPY AND MAGNETIZATION IN GRBs

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

Gao, He; Zhang, Bing, E-mail: gaohe@physics.unlv.edu, E-mail: zhang@physics.unlv.edu, E-mail: hug18@psu.edu

2015-03-10

In view of the recent Fermi observations of gamma-ray burst (GRB) prompt emission spectra, we develop a theory of photosphere emission of a hybrid relativistic outflow with a hot fireball component (defined by dimensionless entropy η) and a cold Poynting-flux component (defined by magnetization σ{sub 0} at the central engine). We consider the scenarios both without and with sub-photospheric magnetic dissipations. Based on a simplified toy model of jet dynamics, we develop two approaches: a 'bottom-up' approach to predict the temperature (for a non-dissipative photosphere) and luminosity of the photosphere emission and its relative brightness for a given pair ofmore » (η, σ{sub 0}); and a 'top-down' approach to diagnose central engine parameters (η and σ{sub 0}) based on the observed quasi-thermal photosphere emission properties. We show that a variety of observed GRB prompt emission spectra with different degrees of photosphere thermal emission can be reproduced by varying η and σ{sub 0} within the non-dissipative photosphere scenario. In order to reproduce the observed spectra, the outflows of most GRBs need to have a significant σ, both at the central engine and at the photosphere. The σ value at 10{sup 15} cm from the central engine (a possible non-thermal emission site) is usually also greater than unity, so that internal-collision-induced magnetic reconnection and turbulence (ICMART) may be the mechanism to power the non-thermal emission. We apply our top-down approach to GRB 110721A and find that the temporal evolution behavior of its blackbody component can be well interpreted with a time-varying (η, σ{sub 0}) at the central engine, instead of invoking a varying engine base size r {sub 0} as proposed by previous authors.« less
Constraining the Type of Central Engine of GRBs with Swift Data

NASA Astrophysics Data System (ADS)

Li, Liang; Wu, Xue-Feng; Lei, Wei-Hua; Dai, Zi-Gao; Lian, En-Wei; Ryde, Felix

2018-06-01

The central engine of gamma-ray bursts (GRBs) is poorly constrained. There exist two main candidates: a fast-rotating black hole and a rapidly spinning magnetar. Furthermore, X-ray plateaus are widely accepted to be the energy injection into the external shock. In this paper, we systematically analyze the Swift/XRT light curves of 101 GRBs having plateau phases and known redshifts (before 2017 May). Since a maximum energy budget (∼2 × 1052 erg) exists for magnetars but not for black holes, this provides a good clue to identifying the type of GRB central engine. We calculate the isotropic kinetic energy E K,iso and the isotropic X-ray energy release E X,iso for individual GRBs. We identify three categories based on how likely a black hole harbors a central engine: “Gold” (9 out of 101; both E X,iso and E K,iso exceed the energy budget), “Silver” (69 out of 101; E X,iso less than the limit but E K,iso greater than the limit), and “Bronze” (23 out of 101; the energies are not above the limit). We then derive and test the black hole parameters with the Blandford–Znajek mechanism, and find that the observations of the black hole candidate (“Gold” + “Silver”) samples are consistent with the expectations of the black hole model. Furthermore, we also test the magnetar candidate (“Bronze”) sample with the magnetar model, and find that the magnetar surface magnetic field (B p ) and initial spin period (P 0) fall into reasonable ranges. Our analysis indicates that if the magnetar wind is isotropic, a magnetar central engine is possible for 20% of the analyzed GRBs. For most GRBs, a black hole is most likely operating.
77 FR 33560 - Woodland Rail, LLC-Acquisition and Operation Exemption-Line of Maine Central Railroad Co.

Federal Register 2010, 2011, 2012, 2013, 2014

2012-06-06

... United States. The end points of the Line are at engineering station 64+17 in Baileyville and engineering... Woodland Junction, Me., which is engineering station 363+45, and engineering station 393+37, and another spur track at St. Croix Junction, Me., which is engineering station 6817+12.\\1\\ \\1\\ In a related...
[Micro/nano-engineering to control growth of neuronal cells and tissue engineering applied to the central nervous system].

PubMed

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. © Société de Biologie, 2014.
How gravitational-wave observations can shape the gamma-ray burst paradigm

NASA Astrophysics Data System (ADS)

Bartos, I.; Brady, P.; Márka, S.

2013-06-01

By reaching through shrouding blastwaves, efficiently discovering off-axis events and probing the central engine at work, gravitational wave (GW) observations will soon revolutionize the study of gamma-ray bursts. Already, analyses of GW data targeting gamma-ray bursts have helped constrain the central engines of selected events. Advanced GW detectors with significantly improved sensitivities are under construction. After outlining the GW emission mechanisms from gamma-ray burst progenitors (binary coalescences, stellar core collapses, magnetars and others) that may be detectable with advanced detectors, we review how GWs will improve our understanding of gamma-ray burst central engines, their astrophysical formation channels and the prospects and methods for different search strategies. We place special emphasis on multimessenger searches. To achieve the most scientific benefit, GW, electromagnetic and neutrino observations should be combined to provide greater discriminating power and science reach.
The Signature of the Central Engine in the Weakest Relativistic Explosions: GRB 100316D

NASA Astrophysics Data System (ADS)

Margutti, R.; Soderberg, A. M.; Wieringa, M. H.; Edwards, P. G.; Chevalier, R. A.; Morsony, B. J.; Barniol Duran, R.; Sironi, L.; Zauderer, B. A.; Milisavljevic, D.; Kamble, A.; Pian, E.

2013-11-01

We present late-time radio and X-ray observations of the nearby sub-energetic gamma-ray burst (GRB)100316D associated with supernova (SN) 2010bh. Our broad-band analysis constrains the explosion properties of GRB 100316D to be intermediate between highly relativistic, collimated GRBs and the spherical, ordinary hydrogen-stripped SNe. We find that ~1049 erg is coupled to mildly relativistic (Γ = 1.5-2), quasi-spherical ejecta, expanding into a medium previously shaped by the progenitor mass-loss with a rate of \\dot{M}\\, {\\sim }\\, 10^{-5}\\,M_{\\odot }\\,yr^{-1} (for an assumed wind density profile and wind velocity vw = 1000 km s-1). The kinetic energy profile of the ejecta argues for the presence of a central engine and identifies GRB 100316D as one of the weakest central-engine-driven explosions detected to date. Emission from the central engine is responsible for an excess of soft X-ray radiation that dominates over the standard afterglow at late times (t > 10 days). We connect this phenomenology with the birth of the most rapidly rotating magnetars. Alternatively, accretion onto a newly formed black hole might explain the excess of radiation. However, significant departure from the standard fall-back scenario is required.
Magnetar-powered Supernovae in Two Dimensions. II. Broad-line Supernovae Ic

NASA Astrophysics Data System (ADS)

Chen, Ke-Jung; Moriya, Takashi J.; Woosley, Stan; Sukhbold, Tuguldur; Whalen, Daniel J.; Suwa, Yudai; Bromm, Volker

2017-04-01

Nascent neutron stars (NSs) with millisecond periods and magnetic fields in excess of 1016 Gauss can drive highly energetic and asymmetric explosions known as magnetar-powered supernovae. These exotic explosions are one theoretical interpretation for supernovae Ic-BL, which are sometimes associated with long gamma-ray bursts. Twisted magnetic field lines extract the rotational energy of the NS and release it as a disk wind or a jet with energies greater than 1052 erg over ˜20 s. What fraction of the energy of the central engine go into the wind and the jet remain unclear. We have performed two-dimensional hydrodynamical simulations of magnetar-powered supernovae (SNe) driven by disk winds and jets with the CASTRO code to investigate the effect of the central engine on nucleosynthetic yields, mixing, and light curves. We find that these explosions synthesize less than 0.05 {M}⊙ of {}56{Ni} and that this mass is not very sensitive to central engine type. The morphology of the explosion can provide a powerful diagnostic of the properties of the central engine. In the absence of a circumstellar medium, these events are not very luminous, with peak bolometric magnitudes of {M}b˜ -16.5 due to low {}56{Ni} production.
Relevance of Local Flexibility Near the Active Site for Enzymatic Catalysis: Biochemical Characterization and Engineering of Cellulase Cel5A From Bacillus agaradherans.

PubMed

Saavedra, Juan M; Azócar, Mauricio A; Rodríguez, Vida; Ramírez-Sarmiento, César A; Andrews, Barbara A; Asenjo, Juan A; Parra, Loreto P

2018-03-25

Detailed molecular mechanisms underpinning enzymatic reactions are still a central problem in biochemistry. The need for active site flexibility to sustain catalytic activity constitutes a notion of wide acceptance, although its direct influence remains to be fully understood. With the aim of studying the relationship between structural dynamics and enzyme catalysis, the cellulase Cel5A from Bacillus agaradherans is used as a model for in silico comparative analysis with mesophilic and psychrophilic counterparts. Structural features that determine flexibility are related to kinetic and thermodynamic parameters of catalysis. As a result, three specific positions in the vicinity of the active site of Cel5A are selected for protein engineering via site-directed mutagenesis. Three Cel5A variants are generated, N141L, A137Y and I102A/A137Y, showing a concomitant increase in the catalytic activity at low temperatures and a decrease in activation energy and activation enthalpy, similar to cold-active enzymes. These results are interpreted in structural terms by molecular dynamics simulations, showing that disrupting a hydrogen bond network in the vicinity of the active site increases local flexibility. These results provide a structural framework for explaining the changes in thermodynamic parameters observed between homologous enzymes with varying temperature adaptations. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Influence of Science, Technology, and Engineering Curriculum on Rural Midwestern High School Student Career Decisions

NASA Astrophysics Data System (ADS)

Killingsworth, John

Low degree completion in technical and engineering degrees is a growing concern for policymakers and educators in the United States. This study was an examination of the behaviors of adolescents specific to career decisions related to technology and engineering. The central research question for this study was: do rural, Midwestern high school technical and engineering curricula serve to engage students sufficiently to encourage them to persist through high school while sustaining their interests in technology and engineering careers? Engaging students in technology and engineering fields is the challenge for educators throughout the country and the Midwest. Rural schools have the additional challenge of meeting those issues because of resource limitations. Students in three Midwestern schools were surveyed to determine the level of interest in technology and engineering. The generalized likelihood ratio test was used to overcome concerns for small sample sizes. Accounting for dependent variables, multiple independent variables are examined using descriptive statistics to determine which have greater influence on career decisions, specifically those related to technology and engineering. A typical science curriculum is defined for rural Midwestern high schools. This study concludes that such curriculum achieves the goal of maintaining or increasing student interest and engagement in STEM careers. Furthermore, those schools that incorporate contextual and experiential learning activities into the curriculum demonstrate increased results in influencing student career choices toward technology and engineering careers. Implications for parents, educators, and industry professionals are discussed.
Environmental Assessment: Communications-Electronics Research, Development and Engineering Command (CERDEC) Flight Activity Facility at the Joint Base McGuire-Dix-Lakehurst, New Jersey

DTIC Science & Technology

2013-01-01

portions of the original Lakehurst Proving Ground operations, specifically a goat pasture and associated farm buildings, were located within the project...would continue to receive fuel from the centrally managed fuel farm operation located south of Hangar 6. • The facility would connect to existing...Rounds Road. An undated map6 from the Lakehurst Proving Ground era depicts the project study area as a fenced goat pasture. 3.2.1 Zoning and
Simulation and analysis of the interactions between split gradient coils and a split magnet cryostat in an MRI-PET system.

PubMed

Liu, Limei; Sanchez-Lopez, Hector; Poole, Michael; Liu, Feng; Crozier, Stuart

2012-09-01

Splitting a magnetic resonance imaging (MRI) magnet into two halves can provide a central region to accommodate other modalities, such as positron emission tomography (PET). This approach, however, produces challenges in the design of the gradient coils in terms of gradient performance and fabrication. In this paper, the impact of a central gap in a split MRI system was theoretically studied by analysing the performance of split, actively-shielded transverse gradient coils. In addition, the effects of the eddy currents induced in the cryostat on power loss, mechanical vibration and magnetic field harmonics were also investigated. It was found, as expected, that the gradient performance tended to decrease as the central gap increased. Furthermore, the effects of the eddy currents were heightened as a consequence of splitting the gradient assembly into two halves. An optimal central gap size was found, such that the split gradient coils designed with this central gap size could produce an engineering solution with an acceptable trade-off between gradient performance and eddy current effects. These investigations provide useful information on the inherent trade-offs in hybrid MRI imaging systems. Copyright © 2012 Elsevier Inc. All rights reserved.
Restoration of active gully systems following the implementation of bioengineering techniques.

NASA Astrophysics Data System (ADS)

Borja, Pablo; Vanacker, Veerle; Govers, Gerard

2015-04-01

Intensive land use in the central parts of the Andean basin has led to widespread land degradation. The formation of badlands dates back from the 1950s and 1960s. Several studies indicate that human activities have accelerated mountain erosion rates by up to 100 times. In this study, we have evaluated the effects of bio-engineering works aiming to stabilize degraded catchments. Five micro-catchments (0.2 up to 5 ha) have been selected within a 3 km2 area in the lower part of the Loreto catchment (Southern Ecuadorian Andes). The five micro-catchments differ in vegetation cover and implementation of bio-engineering works. The experimental design consisted of three micro-catchments: (1) DI with conservation works, (2) DF with reforestation by Eucalyptus sp and (3) DT with no conservation works. Two micro-catchments have been monitored in an agricultural area: with (AI) and without (AT) bio-engineering works in the active gullies. Small checkdams were constructed in the gully floors of two of the micro-catchments in the badland area (DI) and the agricultural area (AI). The checkdams are made of wood and tires. Water flow has been measured in every micro-catchment, while sediment traps were constructed to monitor sediment transport. Results show that bio-engineering techniques are effective to stabilize active gullies. Deposition of sediments in manmade dams is strongly dependent on previous rainfall events, as well as gully channel slope, and its vegetation cover. From the experimental data, an I30 max threshold value was determined. Above this threshold value, all micro-catchments are actively contributing sediment to the main river system. The checkdams built with wood and tires have an efficiency of 70%, and were shown to be very effective to stabilize active gullies in bad lands through significant reduction (about 62%) of the amount of sediment exported from the micro-catchments. Key words: degraded soils, erosion, sediment, restoration, reforestation
The Use of Executive Control Processes in Engineering Design by Engineering Students and Professional Engineers

ERIC Educational Resources Information Center

Dixon, Raymond A.; Johnson, Scott D.

2012-01-01

A cognitive construct that is important when solving engineering design problems is executive control process, or metacognition. It is a central feature of human consciousness that enables one "to be aware of, monitor, and control mental processes." The framework for this study was conceptualized by integrating the model for creative design, which…
40 CFR 1039.627 - What are the incentives for equipment manufacturers to use cleaner engines?

Code of Federal Regulations, 2012 CFR

2012-07-01

... engines. (e) In-use fuel. If the engine manufacturer certifies using ultra low-sulfur diesel fuel, you... commits to a central-fueling facility with ultra low-sulfur diesel fuel throughout its lifetime would meet... 1039: If the engine's maximum power is . . . And you install . . . Certified early to the . . . You may...
40 CFR 1039.627 - What are the incentives for equipment manufacturers to use cleaner engines?

Code of Federal Regulations, 2013 CFR

2013-07-01

... engines. (e) In-use fuel. If the engine manufacturer certifies using ultra low-sulfur diesel fuel, you... commits to a central-fueling facility with ultra low-sulfur diesel fuel throughout its lifetime would meet... 1039: If the engine's maximum power is . . . And you install . . . Certified early to the . . . You may...
40 CFR 1039.627 - What are the incentives for equipment manufacturers to use cleaner engines?

Code of Federal Regulations, 2014 CFR

2014-07-01

... engines. (e) In-use fuel. If the engine manufacturer certifies using ultra low-sulfur diesel fuel, you... commits to a central-fueling facility with ultra low-sulfur diesel fuel throughout its lifetime would meet... 1039: If the engine's maximum power is . . . And you install . . . Certified early to the . . . You may...
Women in science, engineering and technology (SET): a report on the Indonesian experience.

PubMed

Hermawati, W; Luhulima, A S

2000-01-01

This paper presents the preliminary results of a study by the Gender Working Group, Indonesian Institute of Sciences, on women's contribution to, and benefits to women from, science, engineering and technology (SET), specifically the benefits accruing to disadvantaged women in urban and rural areas in Indonesia. Previous studies on the participation of women in SET have shown the under-representation of women in all SET activities, including decision-making and advisory positions. However, some studies have shown that if gender perspectives are included in the design and implementation of development activities, disadvantaged women in urban and rural areas could greatly benefit from SET in development projects. The two case studies in North Sulawesi and Central Lombok provinces show that the projects have enabled the expansion of employment opportunities for women and thus increased their technical skills and income. In addition, the projects have also contributed to enhancing women's self-confidence, self-reliance and communication skills.

The role of the International Space University in building capacity in emerging space nations.

NASA Astrophysics Data System (ADS)

Richards, Robert

The International Space University provides graduate-level training to the future leaders of the emerging global space community at its Central Campus in Strasbourg, France, and at locations around the world. In its two-month Summer Session and one-year Masters program, ISU offers its students a unique Core Curriculum covering all disciplines related to space programs and enterprises - space science, space engineering, systems engineering, space policy and law, business and management, and space and society. Both programs also involve an intense student research Team Project providing international graduate students and young space professionals the opportunity to solve complex problems by working together in an intercultural environment. Since its founding in 1987, ISU has graduated more than 2500 students from 96 countries. Together with hundreds of ISU faculty and lecturers from around the world, ISU alumni comprise an extremely effective network of space professionals and leaders that actively facilitates individual career growth, professional activities and international space cooperation.
Application of an integrated flight/propulsion control design methodology to a STOVL aircraft

NASA Technical Reports Server (NTRS)

Garg, Sanjay; Mattern, Duane L.

1991-01-01

Results are presented from the application of an emerging Integrated Flight/Propulsion Control (IFPC) design methodology to a Short Take Off and Vertical Landing (STOVL) aircraft in transition flight. The steps in the methodology consist of designing command shaping prefilters to provide the overall desired response to pilot command inputs. A previously designed centralized controller is first validated for the integrated airframe/engine plant used. This integrated plant is derived from a different model of the engine subsystem than the one used for the centralized controller design. The centralized controller is then partitioned in a decentralized, hierarchical structure comprising of airframe lateral and longitudinal subcontrollers and an engine subcontroller. Command shaping prefilters from the pilot control effector inputs are then designed and time histories of the closed loop IFPC system response to simulated pilot commands are compared to desired responses based on handling qualities requirements. Finally, the propulsion system safety and nonlinear limited protection logic is wrapped around the engine subcontroller and the response of the closed loop integrated system is evaluated for transients that encounter the propulsion surge margin limit.
Engineering Factor Xa Inhibitor with Multiple Platelet-Binding Sites Facilitates its Platelet Targeting

NASA Astrophysics Data System (ADS)

Zhu, Yuanjun; Li, Ruyi; Lin, Yuan; Shui, Mengyang; Liu, Xiaoyan; Chen, Huan; Wang, Yinye

2016-07-01

Targeted delivery of antithrombotic drugs centralizes the effects in the thrombosis site and reduces the hemorrhage side effects in uninjured vessels. We have recently reported that the platelet-targeting factor Xa (FXa) inhibitors, constructed by engineering one Arg-Gly-Asp (RGD) motif into Ancylostoma caninum anticoagulant peptide 5 (AcAP5), can reduce the risk of systemic bleeding than non-targeted AcAP5 in mouse arterial injury model. Increasing the number of platelet-binding sites of FXa inhibitors may facilitate their adhesion to activated platelets, and further lower the bleeding risks. For this purpose, we introduced three RGD motifs into AcAP5 to generate a variant NR4 containing three platelet-binding sites. NR4 reserved its inherent anti-FXa activity. Protein-protein docking showed that all three RGD motifs were capable of binding to platelet receptor αIIbβ3. Molecular dynamics simulation demonstrated that NR4 has more opportunities to interact with αIIbβ3 than single-RGD-containing NR3. Flow cytometry analysis and rat arterial thrombosis model further confirmed that NR4 possesses enhanced platelet targeting activity. Moreover, NR4-treated mice showed a trend toward less tail bleeding time than NR3-treated mice in carotid artery endothelium injury model. Therefore, our data suggest that engineering multiple binding sites in one recombinant protein is a useful tool to improve its platelet-targeting efficiency.
Novel Therapeutic GPCRs for Psychiatric Disorders

PubMed Central

Komatsu, Hidetoshi

2015-01-01

G protein-coupled receptors (GPCRs) are the most common targets of the neuropharmacological drugs in the central nervous system (CNS). GPCRs are activated by manifold neurotransmitters, and their activation in turn evokes slow synaptic transmission. They are deeply involved in multiple neurological and psychiatric disorders such as Parkinson’s disease and schizophrenia. In the brain, the striatum is strongly innervated by the ventral tegmental area (VTA) and plays a central role in manifestation of psychiatric disorders. Recently, anatomical and comprehensive transcriptome analysis of the non-odorant GPCR superfamily revealed that the orphan GPCRs GPR88, GPR6, and GPR52, as well as dopamine D1 and D2 receptors and the adenosine A2a receptor, are the most highly enriched in the rodent striatum. Genetically engineered animal models and molecular biological studies have suggested that these striatally enriched GPCRs have a potential to be therapeutic psychiatric receptors. This review summarizes the current understanding of the therapeutic GPCR candidates for psychiatric disorders. PMID:26101869
Novel Therapeutic GPCRs for Psychiatric Disorders.

PubMed

Komatsu, Hidetoshi

2015-06-19

G protein-coupled receptors (GPCRs) are the most common targets of the neuropharmacological drugs in the central nervous system (CNS). GPCRs are activated by manifold neurotransmitters, and their activation in turn evokes slow synaptic transmission. They are deeply involved in multiple neurological and psychiatric disorders such as Parkinson's disease and schizophrenia. In the brain, the striatum is strongly innervated by the ventral tegmental area (VTA) and plays a central role in manifestation of psychiatric disorders. Recently, anatomical and comprehensive transcriptome analysis of the non-odorant GPCR superfamily revealed that the orphan GPCRs GPR88, GPR6, and GPR52, as well as dopamine D1 and D2 receptors and the adenosine A2a receptor, are the most highly enriched in the rodent striatum. Genetically engineered animal models and molecular biological studies have suggested that these striatally enriched GPCRs have a potential to be therapeutic psychiatric receptors. This review summarizes the current understanding of the therapeutic GPCR candidates for psychiatric disorders.
MFTF-. cap alpha. + T progress report

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

Nelson, W.D.

1985-04-01

Early in FY 1983, several upgrades of the Mirror Fusion Test Facility (MFTF-B) at Lawrence Livermore National Laboratory (LLNL) were proposed to the fusion community. The one most favorably received was designated MFTF-..cap alpha..+T. The engineering design of this device, guided by LLNL, has been a principal activity of the Fusion Engineering Design Center during FY 1983. This interim progress report represents a snapshot of the device design, which was begun in FY 1983 and will continue for several years. The report is organized as a complete design description. Because it is an interim report, some parts are incomplete; theymore » will be supplied as the design study proceeds. As described in this report, MFTF-..cap alpha..+T uses existing facilities, many MFTF-B components, and a number of innovations to improve on the physics parameters of MFTF-B. It burns deuterium-tritium and has a central-cell Q of 2, a wall loading GAMMA/sub n/ of 2 MW/m/sup 2/ (with a central-cell insert module), and an availability of 10%. The machine is fully shielded, allows hands-on maintenance of components outside the vacuum vessel 24 h after shutdown, and has provisions for repair of all operating components.« less
Search for a Signature of Interaction between Relativistic Jet and Progenitor in Gamma-Ray Bursts

NASA Astrophysics Data System (ADS)

Yoshida, Kazuki; Yoneoku, Daisuke; Sawano, Tatsuya; Ito, Hirotaka; Matsumoto, Jin; Nagataki, Shigehiro

2017-11-01

The time variability of prompt emission in gamma-ray bursts (GRBs) is expected to originate from the temporal behavior of the central engine activity and the jet propagation in the massive stellar envelope. Using a pulse search algorithm for bright GRBs, we investigate the time variability of gamma-ray light curves to search a signature of the interaction between the jet and the inner structure of the progenitor. Since this signature might appear in the earlier phase of prompt emission, we divide the light curves into the initial phase and the late phase by referring to the trigger time and the burst duration of each GRB. We also adopt this algorithm for GRBs associated with supernovae/hypernovae that certainly are accompanied by massive stars. However, there is no difference between each pulse interval distribution described by a lognorma distribution in the two phases. We confirm that this result can be explained by the photospheric emission model if the energy injection of the central engine is not steady or completely periodic but episodic and described by the lognormal distribution with a mean of ˜1 s.
Search for a Signature of Interaction between Relativistic Jet and Progenitor in Gamma-Ray Bursts

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

Yoshida, Kazuki; Yoneoku, Daisuke; Sawano, Tatsuya

The time variability of prompt emission in gamma-ray bursts (GRBs) is expected to originate from the temporal behavior of the central engine activity and the jet propagation in the massive stellar envelope. Using a pulse search algorithm for bright GRBs, we investigate the time variability of gamma-ray light curves to search a signature of the interaction between the jet and the inner structure of the progenitor. Since this signature might appear in the earlier phase of prompt emission, we divide the light curves into the initial phase and the late phase by referring to the trigger time and the burstmore » duration of each GRB. We also adopt this algorithm for GRBs associated with supernovae/hypernovae that certainly are accompanied by massive stars. However, there is no difference between each pulse interval distribution described by a lognorma distribution in the two phases. We confirm that this result can be explained by the photospheric emission model if the energy injection of the central engine is not steady or completely periodic but episodic and described by the lognormal distribution with a mean of ∼1 s.« less
Chimeric antigen receptor engineered stem cells: a novel HIV therapy.

PubMed

Zhen, Anjie; Carrillo, Mayra A; Kitchen, Scott G

2017-03-01

Despite the success of combination antiretroviral therapy (cART) for suppressing HIV and improving patients' quality of life, HIV persists in cART-treated patients and remains an incurable disease. Financial burdens and health consequences of lifelong cART treatment call for novel HIV therapies that result in a permanent cure. Cellular immunity is central in controlling HIV replication. However, HIV adopts numerous strategies to evade immune surveillance. Engineered immunity via genetic manipulation could offer a functional cure by generating cells that have enhanced antiviral activity and are resistant to HIV infection. Recently, encouraging reports from several human clinical trials using an anti-CD19 chimeric antigen receptor (CAR) modified T-cell therapy for treating B-cell malignancies have provided valuable insights and generated remarkable enthusiasm in engineered T-cell therapy. In this review, we discuss the development of HIV-specific chimeric antigen receptors and the use of stem cell based therapies to generate lifelong anti-HIV immunity.
Chimeric antigen receptor engineered stem cells: a novel HIV therapy

PubMed Central

Zhen, Anjie; Carrillo, Mayra A; Kitchen, Scott G

2017-01-01

Despite the success of combination antiretroviral therapy (cART) for suppressing HIV and improving patients’ quality of life, HIV persists in cART-treated patients and remains an incurable disease. Financial burdens and health consequences of lifelong cART treatment call for novel HIV therapies that result in a permanent cure. Cellular immunity is central in controlling HIV replication. However, HIV adopts numerous strategies to evade immune surveillance. Engineered immunity via genetic manipulation could offer a functional cure by generating cells that have enhanced antiviral activity and are resistant to HIV infection. Recently, encouraging reports from several human clinical trials using an anti-CD19 chimeric antigen receptor (CAR) modified T-cell therapy for treating B-cell malignancies have provided valuable insights and generated remarkable enthusiasm in engineered T-cell therapy. In this review, we discuss the development of HIV-specific chimeric antigen receptors and the use of stem cell based therapies to generate lifelong anti-HIV immunity. PMID:28357916
Engineering strategy of yeast metabolism for higher alcohol production.

PubMed

Matsuda, Fumio; Furusawa, Chikara; Kondo, Takashi; Ishii, Jun; Shimizu, Hiroshi; Kondo, Akihiko

2011-09-08

While Saccharomyces cerevisiae is a promising host for cost-effective biorefinary processes due to its tolerance to various stresses during fermentation, the metabolically engineered S. cerevisiae strains exhibited rather limited production of higher alcohols than that of Escherichia coli. Since the structure of the central metabolism of S. cerevisiae is distinct from that of E. coli, there might be a problem in the structure of the central metabolism of S. cerevisiae. In this study, the potential production of higher alcohols by S. cerevisiae is compared to that of E. coli by employing metabolic simulation techniques. Based on the simulation results, novel metabolic engineering strategies for improving higher alcohol production by S. cerevisiae were investigated by in silico modifications of the metabolic models of S. cerevisiae. The metabolic simulations confirmed that the high production of butanols and propanols by the metabolically engineered E. coli strains is derived from the flexible behavior of their central metabolism. Reducing this flexibility by gene deletion is an effective strategy to restrict the metabolic states for producing target alcohols. In contrast, the lower yield using S. cerevisiae originates from the structurally limited flexibility of its central metabolism in which gene deletions severely reduced cell growth. The metabolic simulation demonstrated that the poor productivity of S. cerevisiae was improved by the introduction of E. coli genes to compensate the structural difference. This suggested that gene supplementation is a promising strategy for the metabolic engineering of S. cerevisiae to produce higher alcohols which should be the next challenge for the synthetic bioengineering of S. cerevisiae for the efficient production of higher alcohols.
Effect of ethyleneoxide groups of anionic surfactants on lipase activity.

PubMed

Magalhães, Solange S; Alves, Luís; Sebastião, Marco; Medronho, Bruno; Almeida, Zaida L; Faria, Tiago Q; Brito, Rui M M; Moreno, Maria J; Antunes, Filipe E

2016-09-01

The use of enzymes in laundry and dish detergent products is growing. Such tendency implies dedicated studies to understand surfactant-enzyme interactions. The interactions between surfactants and enzymes and their impact on the catalytic efficiency represent a central problem and were here evaluated using circular dichroism, dynamic light scattering, and enzyme activity determinations. This work focuses on this key issue by evaluating the role of the ethyleneoxide (EO) groups of anionic surfactants on the structure and activity of a commercial lipase, and by focusing on the protein/surfactant interactions at a molecular level. The conformational changes and enzymatic activity of the protein were evaluated in the presence of sodium dodecyl sulfate (SDS also denoted as SLE 0 S) and of sodium lauryl ether sulfate with two EO units (SLE 2 S). The results strongly suggest that the presence of EO units in the surfactant polar headgroup determines the stability and the activity of the enzyme. While SDS promotes enzyme denaturation and consequent loss of activity, SLE 2 S preserves the enzyme structure and activity. The data further highlights that the electrostatic interactions among the protein groups are changed by the presence of the adsorbed anionic surfactants being such absorption mainly driven by hydrophobic interactions. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1276-1282, 2016. © 2016 American Institute of Chemical Engineers.
Environments for Fostering Effective Critical Thinking in Geotechnical Engineering Education (Geo-EFFECTs)

ERIC Educational Resources Information Center

Pierce, Charles E.; Gassman, Sarah L.; Huffman, Jeffrey T.

2013-01-01

This paper describes the development, implementation, and assessment of instructional materials for geotechnical engineering concepts using the Environments for Fostering Effective Critical Thinking (EFFECTs) pedagogical framework. The central learning goals of engineering EFFECTs are to (i) improve the understanding and retention of a specific…
48 CFR Appendix A to Part 1219 - Appendix A to Part 1219

Code of Federal Regulations, 2010 CFR

2010-10-01

...* FPDS products and service code (1) Engineering Development AT94 (2) Systems Engineering Services (Only) R414 (3) Radio/TV Communication Equipment (except airborne) 5820 (4) Maintenance, Repair, and Rebuilding of engines, turbines, components and weapons equipment J028/J010 (5) ADP Central Processing Units...
Energy Engineering Analysis (EEA) program for Red River Army Depot, Texas. Executive summary. Final report

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

NONE

The objectives of this Energy Engineering Analysis (EEA) for RRAD were three fold: Develop a systematic plan of projects which will result in reducing energy consumption. Consider renewable energy sources with the objective of establishing an orderly procedure for reducing use of non-renewable energy sources. Determine the feasibility of Total Energy (TE), Selective Energy (SE), and Central Heating Plant (CHP) concepts using alternative fuels. In essence, an assessment of the entire energy picture at RRAD was undertaken. This report is a summary of that effort. RRAD was originally built during 1941 and 1942 as a reserve ordnance depot for themore » Army. Since then, the missions and activities at RRAD have broadened to the point that it is now one of the largest Army depots in the continental United States. Located just west of Texarkana, Texas, RRAD encompasses an area of approximately 19,886 acres. The primary missions at RRAD are general supply and maintenance of vital Army equipment and ordnance material. The supply activities constitute the stocking, distribution, storage and supply of general Army supplies for the central region of the United States. Supply of vehicles, ammunition and guided missiles from RRAD encompasses a much larger region. The maintenance and repair functions at RRAD consists of the overhaul, modification, conversion and repair of automotive equipment and combat vehicles, missile systems and components, armament, and ammunition. Approximately 5500 people are currently employed at RRAD to carry out its mission.« less
Identification of Key Functional Residues in the Active Site of Human β1,4-Galactosyltransferase 7

PubMed Central

Talhaoui, Ibtissam; Bui, Catherine; Oriol, Rafael; Mulliert, Guillermo; Gulberti, Sandrine; Netter, Patrick; Coughtrie, Michael W. H.; Ouzzine, Mohamed; Fournel-Gigleux, Sylvie

2010-01-01

Glycosaminoglycans (GAGs) play a central role in many pathophysiological events, and exogenous xyloside substrates of β1,4-galactosyltransferase 7 (β4GalT7), a major enzyme of GAG biosynthesis, have interesting biomedical applications. To predict functional peptide regions important for substrate binding and activity of human β4GalT7, we conducted a phylogenetic analysis of the β1,4-galactosyltransferase family and generated a molecular model using the x-ray structure of Drosophila β4GalT7-UDP as template. Two evolutionary conserved motifs, 163DVD165 and 221FWGWGREDDE230, are central in the organization of the enzyme active site. This model was challenged by systematic engineering of point mutations, combined with in vitro and ex vivo functional assays. Investigation of the kinetic properties of purified recombinant wild-type β4GalT7 and selected mutants identified Trp224 as a key residue governing both donor and acceptor substrate binding. Our results also suggested the involvement of the canonical carboxylate residue Asp228 acting as general base in the reaction catalyzed by human β4GalT7. Importantly, ex vivo functional tests demonstrated that regulation of GAG synthesis is highly responsive to modification of these key active site amino acids. Interestingly, engineering mutants at position 224 allowed us to modify the affinity and to modulate the specificity of human β4GalT7 toward UDP-sugars and xyloside acceptors. Furthermore, the W224H mutant was able to sustain decorin GAG chain substitution but not GAG synthesis from exogenously added xyloside. Altogether, this study provides novel insight into human β4GalT7 active site functional domains, allowing manipulation of this enzyme critical for the regulation of GAG synthesis. A better understanding of the mechanism underlying GAG assembly paves the way toward GAG-based therapeutics. PMID:20843813
Multidisciplinary Design Technology Development: A Comparative Investigation of Integrated Aerospace Vehicle Design Tools

NASA Technical Reports Server (NTRS)

Renaud, John E.; Batill, Stephen M.; Brockman, Jay B.

1998-01-01

This research effort is a joint program between the Departments of Aerospace and Mechanical Engineering and the Computer Science and Engineering Department at the University of Notre Dame. Three Principal Investigators; Drs. Renaud, Brockman and Batill directed this effort. During the four and a half year grant period, six Aerospace and Mechanical Engineering Ph.D. students and one Masters student received full or partial support, while four Computer Science and Engineering Ph.D. students and one Masters student were supported. During each of the summers up to four undergraduate students were involved in related research activities. The purpose of the project was to develop a framework and systematic methodology to facilitate the application of Multidisciplinary Design Optimization (N4DO) to a diverse class of system design problems. For all practical aerospace systems, the design of a systems is a complex sequence of events which integrates the activities of a variety of discipline "experts" and their associated "tools". The development, archiving and exchange of information between these individual experts is central to the design task and it is this information which provides the basis for these experts to make coordinated design decisions (i.e., compromises and trade-offs) - resulting in the final product design. Grant efforts focused on developing and evaluating frameworks for effective design coordination within a MDO environment. Central to these research efforts was the concept that the individual discipline "expert", using the most appropriate "tools" available and the most complete description of the system should be empowered to have the greatest impact on the design decisions and final design. This means that the overall process must be highly interactive and efficiently conducted if the resulting design is to be developed in a manner consistent with cost and time requirements. The methods developed as part of this research effort include; extensions to a sensitivity based Concurrent Subspace Optimization (CSSO) MDO algorithm; the development of a neural network response surface based CSSO-MDO algorithm; and the integration of distributed computing and process scheduling into the MDO environment. This report overviews research efforts in each of these focus. A complete bibliography of research produced with support of this grant is attached.
An Improved Forensic Science Information Search.

PubMed

Teitelbaum, J

2015-01-01

Although thousands of search engines and databases are available online, finding answers to specific forensic science questions can be a challenge even to experienced Internet users. Because there is no central repository for forensic science information, and because of the sheer number of disciplines under the forensic science umbrella, forensic scientists are often unable to locate material that is relevant to their needs. The author contends that using six publicly accessible search engines and databases can produce high-quality search results. The six resources are Google, PubMed, Google Scholar, Google Books, WorldCat, and the National Criminal Justice Reference Service. Carefully selected keywords and keyword combinations, designating a keyword phrase so that the search engine will search on the phrase and not individual keywords, and prompting search engines to retrieve PDF files are among the techniques discussed. Copyright © 2015 Central Police University.
Development of High Efficiency Clean Combustion Engine Designs for Spark-Ignition and Compression-Ignition Internal Combustion Engines

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

Marriott, Craig; Gonzalez, Manual; Russell, Durrett

2011-06-30

This report summarizes activities related to the revised STATEMENT OF PROJECT OBJECTIVES (SOPO) dated June 2010 for the Development of High-Efficiency Clean Combustion engine Designs for Spark-Ignition and Compression-Ignition Internal Combustion Engines (COOPERATIVE AGREEMENT NUMBER DE-FC26-05NT42415) project. In both the spark- (SI) and compression-ignition (CI) development activities covered in this program, the goal was to develop potential production-viable internal combustion engine system technologies that both reduce fuel consumption and simultaneously met exhaust emission targets. To be production-viable, engine technologies were also evaluated to determine if they would meet customer expectations of refinement in terms of noise, vibration, performance, driveability, etc.more » in addition to having an attractive business case and value. Prior to this activity, only proprietary theoretical / laboratory knowledge existed on the combustion technologies explored The research reported here expands and develops this knowledge to determine series-production viability. Significant SI and CI engine development occurred during this program within General Motors, LLC over more than five years. In the SI program, several engines were designed and developed that used both a relatively simple multi-lift valve train system and a Fully Flexible Valve Actuation (FFVA) system to enable a Homogeneous Charge Compression Ignition (HCCI) combustion process. Many technical challenges, which were unknown at the start of this program, were identified and systematically resolved through analysis, test and development. This report documents the challenges and solutions for each SOPO deliverable. As a result of the project activities, the production viability of the developed clean combustion technologies has been determined. At this time, HCCI combustion for SI engines is not considered production-viable for several reasons. HCCI combustion is excessively sensitive to control variables such as internal dilution level and charge temperature. As a result, HCCI combustion has limited robustness when variables exceed the required narrow ranges determined in this program. HCCI combustion is also not available for the entire range of production engine speeds and loads, (i.e., the dynamic range is limited). Thus, regular SI combustion must be employed for a majority of the full dynamic range of the engine. This degrades the potential fuel economy impact of HCCI combustion. Currently-available combustion control actuators for the simple valve train system engine do not have the authority for continuous air - fuel or torque control for managing the combustion mode transitions between SI and HCCI and thus, require further refinement to meet customer refinement expectations. HCCI combustion control sensors require further development to enable robust long-term HCCI combustion control. Finally, the added technologies required to effectively manage HCCI combustion such as electric cam phasers, central direct fuel injection, cylinder pressure sensing, high-flow exhaust gas recirculation system, etc. add excessive on-engine cost and complexity that erodes the production-viability business« less
14. Drawing showing stress for central viaduct, Walworth Run portion ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. Drawing showing stress for central viaduct, Walworth Run portion 1885. Drawing courtesy Engineering Department, City of Cleveland. - Abbey Avenue Viaduct, Spanning Walworth Valley at Abbey Avenue, Cleveland, Cuyahoga County, OH

Computer graphics and the graphic artist

NASA Technical Reports Server (NTRS)

Taylor, N. L.; Fedors, E. G.; Pinelli, T. E.

1985-01-01

A centralized computer graphics system is being developed at the NASA Langley Research Center. This system was required to satisfy multiuser needs, ranging from presentation quality graphics prepared by a graphic artist to 16-mm movie simulations generated by engineers and scientists. While the major thrust of the central graphics system was directed toward engineering and scientific applications, hardware and software capabilities to support the graphic artists were integrated into the design. This paper briefly discusses the importance of computer graphics in research; the central graphics system in terms of systems, software, and hardware requirements; the application of computer graphics to graphic arts, discussed in terms of the requirements for a graphic arts workstation; and the problems encountered in applying computer graphics to the graphic arts. The paper concludes by presenting the status of the central graphics system.
BADERI: an online database to coordinate handsearching activities of controlled clinical trials for their potential inclusion in systematic reviews.

PubMed

Pardo-Hernandez, Hector; Urrútia, Gerard; Barajas-Nava, Leticia A; Buitrago-Garcia, Diana; Garzón, Julieth Vanessa; Martínez-Zapata, María José; Bonfill, Xavier

2017-06-13

Systematic reviews provide the best evidence on the effect of health care interventions. They rely on comprehensive access to the available scientific literature. Electronic search strategies alone may not suffice, requiring the implementation of a handsearching approach. We have developed a database to provide an Internet-based platform from which handsearching activities can be coordinated, including a procedure to streamline the submission of these references into CENTRAL, the Cochrane Collaboration Central Register of Controlled Trials. We developed a database and a descriptive analysis. Through brainstorming and discussion among stakeholders involved in handsearching projects, we designed a database that met identified needs that had to be addressed in order to ensure the viability of handsearching activities. Three handsearching teams pilot tested the proposed database. Once the final version of the database was approved, we proceeded to train the staff involved in handsearching. The proposed database is called BADERI (Database of Iberoamerican Clinical Trials and Journals, by its initials in Spanish). BADERI was officially launched in October 2015, and it can be accessed at www.baderi.com/login.php free of cost. BADERI has an administration subsection, from which the roles of users are managed; a references subsection, where information associated to identified controlled clinical trials (CCTs) can be entered; a reports subsection, from which reports can be generated to track and analyse the results of handsearching activities; and a built-in free text search engine. BADERI allows all references to be exported in ProCite files that can be directly uploaded into CENTRAL. To date, 6284 references to CCTs have been uploaded to BADERI and sent to CENTRAL. The identified CCTs were published in a total of 420 journals related to 46 medical specialties. The year of publication ranged between 1957 and 2016. BADERI allows the efficient management of handsearching activities across different countries and institutions. References to all CCTs available in BADERI can be readily submitted to CENTRAL for their potential inclusion in systematic reviews.
Identifying student difficulties with entropy, heat engines, and the Carnot cycle

NASA Astrophysics Data System (ADS)

Smith, Trevor I.; Christensen, Warren M.; Mountcastle, Donald B.; Thompson, John R.

2015-12-01

[This paper is part of the Focused Collection on Upper Division Physics Courses.] We report on several specific student difficulties regarding the second law of thermodynamics in the context of heat engines within upper-division undergraduate thermal physics courses. Data come from ungraded written surveys, graded homework assignments, and videotaped classroom observations of tutorial activities. Written data show that students in these courses do not clearly articulate the connection between the Carnot cycle and the second law after lecture instruction. This result is consistent both within and across student populations. Observation data provide evidence for myriad difficulties related to entropy and heat engines, including students' struggles in reasoning about situations that are physically impossible and failures to differentiate between differential and net changes of state properties of a system. Results herein may be seen as the application of previously documented difficulties in the context of heat engines, but others are novel and emphasize the subtle and complex nature of cyclic processes and heat engines, which are central to the teaching and learning of thermodynamics and its applications. Moreover, the sophistication of these difficulties is indicative of the more advanced thinking required of students at the upper division, whose developing knowledge and understanding give rise to questions and struggles that are inaccessible to novices.
The delicate balance in genetically engineering live vaccines

PubMed Central

Galen, James E.; Curtiss, Roy

2014-01-01

Contemporary vaccine development relies less on empirical methods of vaccine construction, and now employs a powerful array of precise engineering strategies to construct immunogenic live vaccines. In this review, we will survey various engineering techniques used to create attenuated vaccines, with an emphasis on recent advances and insights. We will further explore the adaptation of attenuated strains to create multivalent vaccine platforms for immunization against multiple unrelated pathogens. These carrier vaccines are engineered to deliver sufficient levels of protective antigens to appropriate lymphoid inductive sites to elicit both carrier-specific and foreign antigen-specific immunity. Although many of these technologies were originally developed for use in Salmonella vaccines, application of the essential logic of these approaches will be extended to development of other enteric vaccines where possible. A central theme driving our discussion will stress that the ultimate success of an engineered vaccine rests on achieving the proper balance between attenuation and immunogenicity. Achieving this balance will avoid over-activation of inflammatory responses, which results in unacceptable reactogenicity, but will retain sufficient metabolic fitness to enable the live vaccine to reach deep tissue inductive sites and trigger protective immunity. The breadth of examples presented herein will clearly demonstrate that genetic engineering offers the potential for rapidly propelling vaccine development forward into novel applications and therapies which will significantly expand the role of vaccines in public health. PMID:24370705
Relativistic neutrons in active galactic nuclei

NASA Technical Reports Server (NTRS)

Sikora, Marek; Begelman, Mitchell C.; Rudak, Bronislaw

1989-01-01

The acceleration of protons to relativistic energies in active galactic nuclei leads to the creation of relativistic neutrons which escape from the central engine. The neutrons decay at distances of up to 1-100 pc, depositing their energies and momenta in situ. Energy deposition by decaying neutrons may inhibit spherical accretion and drive a wind, which could be responsible for the velocity fields in emission-line regions and the outflow of broad absorption line systems. Enhanced pressure in the neutron decay region may also help to confine emission line clouds. A fraction of the relativistic proton energy is radiated in gamma-rays with energies which may be as large as about 100,000 GeV.
Communication Needs Assessment for Distributed Turbine Engine Control

NASA Technical Reports Server (NTRS)

Culley, Dennis E.; Behbahani, Alireza R.

2008-01-01

Control system architecture is a major contributor to future propulsion engine performance enhancement and life cycle cost reduction. The control system architecture can be a means to effect net weight reduction in future engine systems, provide a streamlined approach to system design and implementation, and enable new opportunities for performance optimization and increased awareness about system health. The transition from a centralized, point-to-point analog control topology to a modular, networked, distributed system is paramount to extracting these system improvements. However, distributed engine control systems are only possible through the successful design and implementation of a suitable communication system. In a networked system, understanding the data flow between control elements is a fundamental requirement for specifying the communication architecture which, itself, is dependent on the functional capability of electronics in the engine environment. This paper presents an assessment of the communication needs for distributed control using strawman designs and relates how system design decisions relate to overall goals as we progress from the baseline centralized architecture, through partially distributed and fully distributed control systems.
Mobility Data Analytics Center.

DOT National Transportation Integrated Search

2016-01-01

Mobility Data Analytics Center aims at building a centralized data engine to efficiently manipulate : large-scale data for smart decision making. Integrating and learning the massive data are the key to : the data engine. The ultimate goal of underst...
Recognizing and engineering digital-like logic gates and switches in gene regulatory networks.

PubMed

Bradley, Robert W; Buck, Martin; Wang, Baojun

2016-10-01

A central aim of synthetic biology is to build organisms that can perform useful activities in response to specified conditions. The digital computing paradigm which has proved so successful in electrical engineering is being mapped to synthetic biological systems to allow them to make such decisions. However, stochastic molecular processes have graded input-output functions, thus, bioengineers must select those with desirable characteristics and refine their transfer functions to build logic gates with digital-like switching behaviour. Recent efforts in genome mining and the development of programmable RNA-based switches, especially CRISPRi, have greatly increased the number of parts available to synthetic biologists. Improvements to the digital characteristics of these parts are required to enable robust predictable design of deeply layered logic circuits. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.
DISCOVERY OF CANDIDATE H{sub 2}O DISK MASERS IN ACTIVE GALACTIC NUCLEI AND ESTIMATIONS OF CENTRIPETAL ACCELERATIONS

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

Greenhill, Lincoln J.; Moran, James M.; Tilak, Avanti

2009-12-10

Based on spectroscopic signatures, about one-third of known H{sub 2}O maser sources in active galactic nuclei (AGNs) are believed to arise in highly inclined accretion disks around central engines. These 'disk maser candidates' are of interest primarily because angular structure and rotation curves can be resolved with interferometers, enabling dynamical study. We identify five new disk maser candidates in studies with the Green Bank Telescope, bringing the total number published to 30. We discovered two (NGC 1320, NGC 17) in a survey of 40 inclined active galaxies (v {sub sys} < 20, 000 km s{sup -1}). The remaining three diskmore » maser candidates were identified in monitoring of known sources: NGC 449, NGC 2979, and NGC 3735. We also confirm a previously marginal case in UGC 4203. For the disk maser candidates reported here, inferred rotation speeds are 130-500 km s{sup -1}. Monitoring of three more rapidly rotating candidate disks (CG 211, NGC 6264, VV 340A) has enabled measurement of likely orbital centripetal acceleration, and estimation of central masses ((2-7) x10{sup 7} M {sub sun}) and mean disk radii (0.2-0.4 pc). Accelerations may ultimately permit estimation of distances when combined with interferometer data. This is notable because the three AGNs are relatively distant (10,000 km s{sup -1}
DISCOS- Current Status and Future Developments

NASA Astrophysics Data System (ADS)

Flohrer, T.; Lemmens, S.; Bastida Virgili, B.; Krag, H.; Klinkrad, H.; Parrilla, E.; Sanchez, N.; Oliveira, J.; Pina, F.

2013-08-01

We present ESA's Database and Information System Characterizing Objects in Space (DISCOS). DISCOS not only plays an essential role in the collision avoidance and re-entry prediction services provided by ESA's Space Debris Office, it is also providing input to numerous and very differently scoped engineering activities, within ESA and throughout industry. We introduce the central functionalities of DISCOS, present the available reporting capabilities, and describe selected data modelling features. Finally, we revisit the developments of the recent years and take a sneak preview of the on-going replacement of DISCOS web front-end.
CT-assisted agile manufacturing

NASA Astrophysics Data System (ADS)

Stanley, James H.; Yancey, Robert N.

1996-11-01

The next century will witness at least two great revolutions in the way goods are produced. First, workers will use the medium of virtual reality in all aspects of marketing, research, development, prototyping, manufacturing, sales and service. Second, market forces will drive manufacturing towards small-lot production and just-in-time delivery. Already, we can discern the merging of these megatrends into what some are calling agile manufacturing. Under this new paradigm, parts and processes will be designed and engineered within the mind of a computer, tooled and manufactured by the offspring of today's rapid prototyping equipment, and evaluated for performance and reliability by advanced nondestructive evaluation (NDE) techniques and sophisticated computational models. Computed tomography (CT) is the premier example of an NDE method suitable for future agile manufacturing activities. It is the only modality that provides convenient access to the full suite of engineering data that users will need to avail themselves of computer- aided design, computer-aided manufacturing, and computer- aided engineering capabilities, as well as newly emerging reverse engineering, rapid prototyping and solid freeform fabrication technologies. As such, CT is assured a central, utilitarian role in future industrial operations. An overview of this exciting future for industrial CT is presented.
Jet Engine Control Using Ethernet with a BRAIN (Postprint)

DTIC Science & Technology

2008-07-01

current communications may be mitigated. 15. SUBJECT TERMS BRAIN, Braided Ring Availability Integrity Network, Gas turbine, FADEC , disturbed...urrent state of the art engine controls have converged on the notion of the Full Authority Digital Engine Control ( FADEC ), which consists of a centralized...is completely dependent on the proper operation of the controller. In current systems, the FADEC is often located on the relatively cool engine fan
40 CFR 52.1126 - Control strategy: Sulfur oxides.

Code of Federal Regulations, 2012 CFR

2012-07-01

... granted by the Massachusetts Department of Environmental Quality Engineering.) Massachusetts Mutual Life... stack). Central Massachusetts APCD Borden, Inc., Chemical Division, Leominster (conditioned upon first... Department of Environmental Quality Engineering.). Gardner State Hospital, Gardner. Grafton State Hospital...
40 CFR 52.1126 - Control strategy: Sulfur oxides.

Code of Federal Regulations, 2010 CFR

2010-07-01

... granted by the Massachusetts Department of Environmental Quality Engineering.) Massachusetts Mutual Life... stack). Central Massachusetts APCD Borden, Inc., Chemical Division, Leominster (conditioned upon first... Department of Environmental Quality Engineering.). Gardner State Hospital, Gardner. Grafton State Hospital...
40 CFR 52.1126 - Control strategy: Sulfur oxides.

Code of Federal Regulations, 2011 CFR

2011-07-01

... granted by the Massachusetts Department of Environmental Quality Engineering.) Massachusetts Mutual Life... stack). Central Massachusetts APCD Borden, Inc., Chemical Division, Leominster (conditioned upon first... Department of Environmental Quality Engineering.). Gardner State Hospital, Gardner. Grafton State Hospital...
75 FR 883 - Environmental Impact Statement; Maricopa County, AZ

Federal Register 2010, 2011, 2012, 2013, 2014

2010-01-06

...: Kenneth Davis, Senior Engineering Manager for Operations, Federal Highway Administration, 4000 N. Central..., 2009. Kenneth H. Davis, Senior Engineering Manager for Operations, Federal Highway Administration... Research, Planning and Construction. The regulations implementing Executive Order 12372 regarding...
Aircraft engine with inter-turbine engine frame supported counter rotating low pressure turbine rotors

NASA Technical Reports Server (NTRS)

Seda, Jorge F. (Inventor); Dunbar, Lawrence W. (Inventor); Gliebe, Philip R. (Inventor); Szucs, Peter N. (Inventor); Brauer, John C. (Inventor); Johnson, James E. (Inventor); Moniz, Thomas (Inventor); Steinmetz, Gregory T. (Inventor)

2003-01-01

An aircraft gas turbine engine assembly includes an inter-turbine frame axially located between high and low pressure turbines. Low pressure turbine has counter rotating low pressure inner and outer rotors with low pressure inner and outer shafts which are at least in part rotatably disposed co-axially within a high pressure rotor. Inter-turbine frame includes radially spaced apart radially outer first and inner second structural rings disposed co-axially about a centerline and connected by a plurality of circumferentially spaced apart struts. Forward and aft sump members having forward and aft central bores are fixedly joined to axially spaced apart forward and aft portions of the inter-turbine frame. Low pressure inner and outer rotors are rotatably supported by a second turbine frame bearing mounted in aft central bore of aft sump member. A mount for connecting the engine to an aircraft is located on first structural ring.
Engineering the architectural diversity of heterogeneous metallic nanocrystals.

PubMed

Yu, Yue; Zhang, Qingbo; Xie, Jianping; Lee, Jim Yang

2013-01-01

Similar to molecular engineering where structural diversity is used to create more property variations for application explorations, the architectural engineering of heterogeneous metallic nanocrystals (HMNCs) can likewise increase the versatility of metallic nanocrystals (NCs). Here we present a synthesis strategy capable of engineering the architectural diversity of HMNCs through rational and independent programming of every architecture-determining element, that is, the shape and size of the component NCs and their spatial arrangement. The strategy is based on the galvanic replacement reaction of a self-sustaining layer formed by underpotential deposition on a polyhedral NC. The selective deposition of satellite NCs on specific site of the central NC is realized by creating a geometry-dependent heterogeneous electron distribution. This site-selective deposition approach is applicable to central NCs in various polyhedral shapes and sizes. The satellite NCs can further develop their own shape and size through crystal growth kinetics control.
Historical review of the international water-resources program of the U.S. Geological Survey, 1940-70

USGS Publications Warehouse

Taylor, George C.

1976-01-01

The review describes the history of the U.S. Geological Survey 's (USGS) activities in international water-resources investigations and institutional development as well as exchange in scientific and applied hydrology during 1940-70. The bulk of these activities has been carried out under the auspices of the U.S. Department of State, U.S. Agency for International Development and its predecessors, the United Nations and its specialized agencies, and the regional intergovernmental agencies. The central objectives of the USGS ' international water-resources activities have been to strengthen the administrative, staff, and operational functions of counterpart governmental hydrological and water-resources agencies; to improve the skills and capabilities of host-country scientific, engineering, and technical personnel; to exchange research specialists and publications in the sharing of advances in hydrological knowledge and methodology; and to participate in mutually beneficial international organizations, symposia, conferences, seminars, and special programs dedicated to various aspects of scientific and applied hydrology. Between 1940 and 1970, USGS hydrogeologists, water chemists, engineers, and hydrologists completed 340 short- and long-term project-oriented international assignments in some 80 host countries. During the same time more than 428 water scientists, engineers, and technicians from 60 countries have received academic and in-service training through USGS water-resources facilities in the United States. Also in this period some 336 reports of a technical and scientific nature have resulted from water-resources projects in the U.S bilateral program. (Woodard-USGS)
29. OVERVIEW OF CENTRAL PART, TO WEST, SHOWING CLERESTORY WINDOWS. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

29. OVERVIEW OF CENTRAL PART, TO WEST, SHOWING CLERESTORY WINDOWS. THE WALL AT REAR IS RECENT, SEPARATING TWO TENANTS' SPACES. - United Engineering Company Shipyard, Inspection & Repair Shops, 2900 Main Street, Alameda, Alameda County, CA

The Education of Future Aeronautical Engineers: Conceiving, Designing, Implementing and Operating

ERIC Educational Resources Information Center

Crawley, Edward F.; Brodeur, Doris R.; Soderholm, Diane H.

2008-01-01

This paper will outline answers to the two central questions regarding improving engineering education: (1) What is the full set of knowledge, skills, and attitudes that engineering students should possess as they leave the university, and at what level of proficiency?; and (2) How can we do better at ensuring that students learn these skills? The…
1. View of engine terminal complex looking westnorthwest from east ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. View of engine terminal complex looking west-northwest from east side of Phillips Drive. Shown are (left to right) the south roundhouse, the machine and blacksmith shops, the storehouse, the oil house, and the coaling sation (behind the oil house in this view). - Central Railroad of New Jersey, Engine Terminal, Jersey City, Hudson County, NJ
32. Photograph of line drawing in possession of the Engineering ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

32. Photograph of line drawing in possession of the Engineering Division of the Directorate of Engineering and Housing, Watervliet Arsenal, New York. SECTIONAL ELEVATIONS OF CENTRAL SECTION AND NORTH WING, UNDATED. SIGNED BY A. VICTORIN. (LEFT HALF OF DRAWING) - Watervliet Arsenal, Building No. 110, Hagner Road between Schull & Whittemore Roads, Watervliet, Albany County, NY
33. Photograph of line drawing in possession of the Engineering ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

33. Photograph of line drawing in possession of the Engineering Division of the Directorate of Engineering and Housing, Watervliet Arsenal, New York. SECTIONAL ELEVATIONS OF CENTRAL SECTION AND NORTH WING, UNDATED. SIGNED BY A. VICTORIN. (RIGHT HALF OF DRAWING) - Watervliet Arsenal, Building No. 110, Hagner Road between Schull & Whittemore Roads, Watervliet, Albany County, NY
A self-controlled trial to evaluate the use of active hearing defenders in the engine rooms of operational naval vessels.

PubMed

Ong, M; Choo, J T L; Low, E

2004-02-01

Active Hearing Defenders are established hearing protectors with in-built electro-acoustics that shut-off ambient noise while allowing effective communication between users. A blinded, self-controlled trial was conducted among naval servicemen to compare the effectiveness of two types of active hearing defenders (Howard-Leight Thunder TM and COM-55) in relation to passive hearing defenders in an operational environment. Subjects felt that the active hearing defenders were more comfortable, durable, and that the active hearing defenders helped them work better. When subjects were tested with a speech discrimination battery (Central Institute of the Deaf, Spondee Word lists), there was a significant difference (p value of 0.04, using the Kruskall-Wallis ANOVA test) between the two active and the passive defenders. However, no significant difference was found between the two types of active hearing defenders. Active hearing defenders are an acceptable and efficacious means of hearing protection in noisy environments.
48 CFR 836.602-4 - Selection authority.

Code of Federal Regulations, 2011 CFR

2011-10-01

... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.602-4 Selection authority. The Director, Office of Construction and Facilities Management (for Central Office contracts), the Director, Office of Construction Management (for National Cemetery Administration contracts...
48 CFR 836.602-4 - Selection authority.

Code of Federal Regulations, 2012 CFR

2012-10-01

... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.602-4 Selection authority. The Director, Office of Construction and Facilities Management (for Central Office contracts), the Director, Office of Construction Management (for National Cemetery Administration contracts...
48 CFR 836.602-4 - Selection authority.

Code of Federal Regulations, 2014 CFR

2014-10-01

... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.602-4 Selection authority. The Director, Office of Construction and Facilities Management (for Central Office contracts), the Director, Office of Construction Management (for National Cemetery Administration contracts...
48 CFR 836.602-4 - Selection authority.

Code of Federal Regulations, 2013 CFR

2013-10-01

... CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect-Engineer Services 836.602-4 Selection authority. The Director, Office of Construction and Facilities Management (for Central Office contracts), the Director, Office of Construction Management (for National Cemetery Administration contracts...
Photographic copy of historic photograph, by Corps of Engineers, U.S. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Photographic copy of historic photograph, by Corps of Engineers, U.S. Army, November 19, 1943 (original in possession of Corps of Engineers, U.S. Army, Pittsburgh District, Engineering Division files) Unit 6, view of WPA masonry wall and dike upstream from Central Avenue Bridge - Johnstown Local Flood Protection Project, Beginning on Conemaugh River approx 3.8 miles downstream from confluence of Little Conemaugh & Stony Creek Rivers at Johnstown, Johnstown, Cambria County, PA
Black Hole Hyperaccretion Inflow–Outflow Model. I. Long and Ultra-long Gamma-Ray Bursts

NASA Astrophysics Data System (ADS)

Liu, Tong; Song, Cui-Ying; Zhang, Bing; Gu, Wei-Min; Heger, Alexander

2018-01-01

Long-duration gamma-ray bursts (LGRBs) and ultra-LGRBs (ULGRBs) originate from collapsars, in the center of which a newborn rotating stellar-mass black hole (BH) surrounded by a massive accretion disk may form. In the scenario of the BH hyperaccretion inflow–outflow model and Blandford–Znajek (BZ) mechanism to trigger gamma-ray bursts (GRBs), the real accretion rate to power a BZ jet is far lower than the mass supply rate from the progenitor star. The characteristics of the progenitor stars can be constrained by GRB luminosity observations, and the results exceed usual expectations. LGRBs lasting from several seconds to tens of seconds in the rest frame may originate from solar-metallicity (Z∼ 1 {Z}ȯ , where Z and {Z}ȯ are the metallicities of progenitor stars and the Sun), massive (M≳ 34 {M}ȯ , where M and {M}ȯ are the masses of progenitor stars and the Sun) stars or some zero-metallicity (Z∼ 0) stars. A fraction of low-metallicity (Z≲ {10}-2 {Z}ȯ ) stars, including Population III stars, can produce ULGRBs such as GRB 111209A. The fraction of LGRBs lasting less than tens of seconds in the rest frame is more than 40%, which cannot conform to the fraction of the demanded type of progenitor star. It possibly implies that the activity timescale of the central engine may be much longer than the observed timescale of prompt emission phase, as indicated by X-ray late-time activities. Alternatively, LGRBs and ULGRBs may be powered by a millisecond magnetar central engine.
Production of Cinnamic and p-Hydroxycinnamic Acids in Engineered Microbes.

PubMed

Vargas-Tah, Alejandra; Gosset, Guillermo

2015-01-01

The aromatic compounds cinnamic and p-hydroxycinnamic acids (pHCAs) are phenylpropanoids having applications as precursors for the synthesis of thermoplastics, flavoring, cosmetic, and health products. These two aromatic acids can be obtained by chemical synthesis or extraction from plant tissues. However, both manufacturing processes have shortcomings, such as the generation of toxic subproducts or a low concentration in plant material. Alternative production methods are being developed to enable the biotechnological production of cinnamic and (pHCAs) by genetically engineering various microbial hosts, including Escherichia coli, Saccharomyces cerevisiae, Pseudomonas putida, and Streptomyces lividans. The natural capacity to synthesize these aromatic acids is not existent in these microbial species. Therefore, genetic modification have been performed that include the heterologous expression of genes encoding phenylalanine ammonia-lyase and tyrosine ammonia-lyase activities, which catalyze the conversion of l-phenylalanine (l-Phe) and l-tyrosine (l-Tyr) to cinnamic acid and (pHCA), respectively. Additional host modifications include the metabolic engineering to increase carbon flow from central metabolism to the l-Phe or l-Tyr biosynthetic pathways. These strategies include the expression of feedback insensitive mutant versions of enzymes from the aromatic pathways, as well as genetic modifications to central carbon metabolism to increase biosynthetic availability of precursors phosphoenolpyruvate and erythrose-4-phosphate. These efforts have been complemented with strain optimization for the utilization of raw material, including various simple carbon sources, as well as sugar polymers and sugar mixtures derived from plant biomass. A systems biology approach to production strains characterization has been limited so far and should yield important data for future strain improvement.
Production of Cinnamic and p-Hydroxycinnamic Acids in Engineered Microbes

PubMed Central

Vargas-Tah, Alejandra; Gosset, Guillermo

2015-01-01

The aromatic compounds cinnamic and p-hydroxycinnamic acids (pHCAs) are phenylpropanoids having applications as precursors for the synthesis of thermoplastics, flavoring, cosmetic, and health products. These two aromatic acids can be obtained by chemical synthesis or extraction from plant tissues. However, both manufacturing processes have shortcomings, such as the generation of toxic subproducts or a low concentration in plant material. Alternative production methods are being developed to enable the biotechnological production of cinnamic and (pHCAs) by genetically engineering various microbial hosts, including Escherichia coli, Saccharomyces cerevisiae, Pseudomonas putida, and Streptomyces lividans. The natural capacity to synthesize these aromatic acids is not existent in these microbial species. Therefore, genetic modification have been performed that include the heterologous expression of genes encoding phenylalanine ammonia-lyase and tyrosine ammonia-lyase activities, which catalyze the conversion of l-phenylalanine (l-Phe) and l-tyrosine (l-Tyr) to cinnamic acid and (pHCA), respectively. Additional host modifications include the metabolic engineering to increase carbon flow from central metabolism to the l-Phe or l-Tyr biosynthetic pathways. These strategies include the expression of feedback insensitive mutant versions of enzymes from the aromatic pathways, as well as genetic modifications to central carbon metabolism to increase biosynthetic availability of precursors phosphoenolpyruvate and erythrose-4-phosphate. These efforts have been complemented with strain optimization for the utilization of raw material, including various simple carbon sources, as well as sugar polymers and sugar mixtures derived from plant biomass. A systems biology approach to production strains characterization has been limited so far and should yield important data for future strain improvement. PMID:26347861
A GRB and Broad-lined Type Ic Supernova from a Single Central Engine

NASA Astrophysics Data System (ADS)

Barnes, Jennifer; Duffell, Paul C.; Liu, Yuqian; Modjaz, Maryam; Bianco, Federica B.; Kasen, Daniel; MacFadyen, Andrew I.

2018-06-01

Unusually high velocities (≳0.1c) and correspondingly high kinetic energies have been observed in a subset of Type Ic supernovae (so-called “broad-lined Ic” supernovae; SNe Ic-BL), prompting a search for a central engine model capable of generating such energetic explosions. A clue to the explosion mechanism may lie in the fact that all supernovae that accompany long-duration gamma-ray bursts (GRBs) belong to the SN Ic-BL class. Using a combination of two-dimensional relativistic hydrodynamics and radiation transport calculations, we demonstrate that the central engine responsible for long GRBs can also trigger an SN Ic-BL. We find that a reasonable GRB engine injected into a stripped Wolf–Rayet progenitor produces a relativistic jet with energy ∼1051 erg, as well as an SN whose synthetic light curves and spectra are fully consistent with observed SNe Ic-BL during the photospheric phase. As a result of the jet’s asymmetric energy injection, the SN spectra and light curves depend on viewing angle. The impact of viewing angle on the spectrum is particularly pronounced at early times, while the viewing-angle dependence for the light curves (∼10% variation in bolometric luminosity) persists throughout the photospheric phase.
A&M. Jet engine test building (TAN609). Exterior. Equipment inside rollup ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

A&M. Jet engine test building (TAN-609). Exterior. Equipment inside roll-up door is blowdown test facility, part of loft-semiscale program. Note width of central section serving as blast protection for operator on left side. Photographer: Cahoon. Date: July 22, 1965. INEEL negative no. 65-3703 - Idaho National Engineering Laboratory, Test Area North, Scoville, Butte County, ID
On Roles of Models in Information Systems

NASA Astrophysics Data System (ADS)

Sølvberg, Arne

The increasing penetration of computers into all aspects of human activity makes it desirable that the interplay among software, data and the domains where computers are applied is made more transparent. An approach to this end is to explicitly relate the modeling concepts of the domains, e.g., natural science, technology and business, to the modeling concepts of software and data. This may make it simpler to build comprehensible integrated models of the interactions between computers and non-computers, e.g., interaction among computers, people, physical processes, biological processes, and administrative processes. This chapter contains an analysis of various facets of the modeling environment for information systems engineering. The lack of satisfactory conceptual modeling tools seems to be central to the unsatisfactory state-of-the-art in establishing information systems. The chapter contains a proposal for defining a concept of information that is relevant to information systems engineering.
Functionalized α-Helical Peptide Hydrogels for Neural Tissue Engineering

PubMed Central

2015-01-01

Trauma to the central and peripheral nervous systems often lead to serious morbidity. Current surgical methods for repairing or replacing such damage have limitations. Tissue engineering offers a potential alternative. Here we show that functionalized α-helical-peptide hydrogels can be used to induce attachment, migration, proliferation and differentiation of murine embryonic neural stem cells (NSCs). Specifically, compared with undecorated gels, those functionalized with Arg-Gly-Asp-Ser (RGDS) peptides increase the proliferative activity of NSCs; promote their directional migration; induce differentiation, with increased expression of microtubule-associated protein-2, and a low expression of glial fibrillary acidic protein; and lead to the formation of larger neurospheres. Electrophysiological measurements from NSCs grown in RGDS-decorated gels indicate developmental progress toward mature neuron-like behavior. Our data indicate that these functional peptide hydrogels may go some way toward overcoming the limitations of current approaches to nerve-tissue repair. PMID:26240838
Solving the 56Ni Puzzle of Magnetar-powered Broad-lined Type IC Supernovae

NASA Astrophysics Data System (ADS)

Wang, Ling-Jun; Han, Yan-Hui; Xu, Dong; Wang, Shan-Qin; Dai, Zi-Gao; Wu, Xue-Feng; Wei, Jian-Yan

2016-11-01

Broad-lined Type Ic supernovae (SNe Ic-BL) are of great importance because their association with long-duration gamma-ray bursts (LGRBs) holds the key to deciphering the central engine of LGRBs, which refrains from being unveiled despite decades of investigation. Among the two popularly hypothesized types of central engine, I.e., black holes and strongly magnetized neutron stars (magnetars), there is mounting evidence that the central engine of GRB-associated SNe (GRB-SNe) is rapidly rotating magnetars. Theoretical analysis also suggests that magnetars could be the central engine of SNe Ic-BL. What puzzled the researchers is the fact that light-curve modeling indicates that as much as 0.2{--}0.5 {M}⊙ of 56Ni was synthesized during the explosion of the SNe Ic-BL, which is unfortunately in direct conflict with current state-of-the-art understanding of magnetar-powered 56Ni synthesis. Here we propose a dynamic model of magnetar-powered SNe to take into account the acceleration of the ejecta by the magnetar, as well as the thermalization of the injected energy. Assuming that the SN kinetic energy comes exclusively from the magnetar acceleration, we find that although a major fraction of the rotational energy of the magnetar is to accelerate the SN ejecta, a tiny fraction of this energy deposited as thermal energy of the ejecta is enough to reduce the needed 56Ni to 0.06 M ⊙ for both SN 1997ef and SN 2007ru. We therefore suggest that magnetars could power SNe Ic-BL in aspects both of energetics and of 56Ni synthesis.
PHYSICS OF OUR DAYS Physical conditions in potential accelerators of ultra-high-energy cosmic rays: updated Hillas plot and radiation-loss constraints

NASA Astrophysics Data System (ADS)

Ptitsyna, Kseniya V.; Troitsky, Sergei V.

2010-10-01

We review basic constraints on the acceleration of ultra-high-energy (UHE) cosmic rays (CRs) in astrophysical sources, namely, the geometric (Hillas) criterion and the restrictions from radiation losses in different acceleration regimes. Using the latest available astrophysical data, we redraw the Hillas plot and find potential UHECR accelerators. For the acceleration in the central engines of active galactic nuclei, we constrain the maximal UHECR energy for a given black hole mass. Among active galaxies, only the most powerful ones, radio galaxies and blazars, are able to accelerate protons to UHE, although acceleration of heavier nuclei is possible in much more abundant lower-power Seyfert galaxies.
Detection of high-energy gamma-ray emission during the X-ray flaring activity in GRB 100728A

DOE PAGES

Abdo, A. A.; Ackermann, M.; Ajello, M.; ...

2011-05-26

Here, we present the simultaneous Swift and Fermi observations of the bright GRB 100728A and its afterglow. The early X-ray emission is dominated by a vigorous flaring activity continuing until 1 ks after the burst. In the same time interval, high-energy emission is significantly detected by the Fermi/Large Area Telescope. Marginal evidence of GeV emission is observed up to later times. As a result, we discuss the broadband properties of this burst within both the internal and external shock scenarios, with a particular emphasis on the relation between X-ray flares, the GeV emission, and a continued long-duration central engine activitymore » as their power source.« less

The Unstructured Paramyxovirus Nucleocapsid Protein Tail Domain Modulates Viral Pathogenesis through Regulation of Transcriptase Activity.

PubMed

Thakkar, Vidhi D; Cox, Robert M; Sawatsky, Bevan; da Fontoura Budaszewski, Renata; Sourimant, Julien; Wabbel, Katrin; Makhsous, Negar; Greninger, Alexander L; von Messling, Veronika; Plemper, Richard K

2018-04-15

The paramyxovirus replication machinery comprises the viral large (L) protein and phosphoprotein (P-protein) in addition to the nucleocapsid (N) protein, which encapsidates the single-stranded RNA genome. Common to paramyxovirus N proteins is a C-terminal tail (Ntail). The mechanistic role and relevance for virus replication of the structurally disordered central Ntail section are unknown. Focusing initially on members of the Morbillivirus genus, a series of measles virus (MeV) and canine distemper virus (CDV) N proteins were generated with internal deletions in the unstructured tail section. N proteins with large tail truncations remained bioactive in mono- and polycistronic minireplicon assays and supported efficient replication of recombinant viruses. Bioactivity of Ntail mutants extended to N proteins derived from highly pathogenic Nipah virus. To probe an effect of Ntail truncations on viral pathogenesis, recombinant CDVs were analyzed in a lethal CDV/ferret model of morbillivirus disease. The recombinant viruses displayed different stages of attenuation ranging from ameliorated clinical symptoms to complete survival of infected animals, depending on the molecular nature of the Ntail truncation. Reinfection of surviving animals with pathogenic CDV revealed robust protection against a lethal challenge. The highly attenuated virus was genetically stable after ex vivo passaging and recovery from infected animals. Mechanistically, gradual viral attenuation coincided with stepwise altered viral transcriptase activity in infected cells. These results identify the central Ntail section as a determinant for viral pathogenesis and establish a novel platform to engineer gradual virus attenuation for next-generation paramyxovirus vaccine design. IMPORTANCE Investigating the role of the paramyxovirus N protein tail domain (Ntail) in virus replication, we demonstrated in this study that the structurally disordered central Ntail region is a determinant for viral pathogenesis. We show that internal deletions in this Ntail region of up to 55 amino acids in length are compatible with efficient replication of recombinant viruses in cell culture but result in gradual viral attenuation in a lethal canine distemper virus (CDV)/ferret model. Mechanistically, we demonstrate a role of the intact Ntail region in the regulation of viral transcriptase activity. Recombinant viruses with Ntail truncations induce protective immunity against lethal challenge of ferrets with pathogenic CDV. This identification of the unstructured central Ntail domain as a nonessential paramyxovirus pathogenesis factor establishes a foundation for harnessing Ntail truncations for vaccine engineering against emerging and reemerging members of the paramyxovirus family. Copyright © 2018 American Society for Microbiology.
Centralized mission planning and scheduling system for the Landsat Data Continuity Mission

USGS Publications Warehouse

Kavelaars, Alicia; Barnoy, Assaf M.; Gregory, Shawna; Garcia, Gonzalo; Talon, Cesar; Greer, Gregory; Williams, Jason; Dulski, Vicki

2014-01-01

Satellites in Low Earth Orbit provide missions with closer range for studying aspects such as geography and topography, but often require efficient utilization of space and ground assets. Optimizing schedules for these satellites amounts to a complex planning puzzle since it requires operators to face issues such as discontinuous ground contacts, limited onboard memory storage, constrained downlink margin, and shared ground antenna resources. To solve this issue for the Landsat Data Continuity Mission (LDCM, Landsat 8), all the scheduling exchanges for science data request, ground/space station contact, and spacecraft maintenance and control will be coordinated through a centralized Mission Planning and Scheduling (MPS) engine, based upon GMV’s scheduling system flexplan9 . The synchronization between all operational functions must be strictly maintained to ensure efficient mission utilization of ground and spacecraft activities while working within the bounds of the space and ground resources, such as Solid State Recorder (SSR) and available antennas. This paper outlines the functionalities that the centralized planning and scheduling system has in its operational control and management of the Landsat 8 spacecraft.
Quaternary Geology and Surface Faulting Hazard: Active and Capable Faults in Central Apennines, Italy

NASA Astrophysics Data System (ADS)

Falcucci, E.; Gori, S.

2015-12-01

The 2009 L'Aquila earthquake (Mw 6.1), in central Italy, raised the issue of surface faulting hazard in Italy, since large urban areas were affected by surface displacement along the causative structure, the Paganica fault. Since then, guidelines for microzonation were drew up that take into consideration the problem of surface faulting in Italy, and laying the bases for future regulations about related hazard, similarly to other countries (e.g. USA). More specific guidelines on the management of areas affected by active and capable faults (i.e. able to produce surface faulting) are going to be released by National Department of Civil Protection; these would define zonation of areas affected by active and capable faults, with prescriptions for land use planning. As such, the guidelines arise the problem of the time interval and general operational criteria to asses fault capability for the Italian territory. As for the chronology, the review of the international literature and regulatory allowed Galadini et al. (2012) to propose different time intervals depending on the ongoing tectonic regime - compressive or extensional - which encompass the Quaternary. As for the operational criteria, the detailed analysis of the large amount of works dealing with active faulting in Italy shows that investigations exclusively based on surface morphological features (e.g. fault planes exposition) or on indirect investigations (geophysical data), are not sufficient or even unreliable to define the presence of an active and capable fault; instead, more accurate geological information on the Quaternary space-time evolution of the areas affected by such tectonic structures is needed. A test area for which active and capable faults can be first mapped based on such a classical but still effective methodological approach can be the central Apennines. Reference Galadini F., Falcucci E., Galli P., Giaccio B., Gori S., Messina P., Moro M., Saroli M., Scardia G., Sposato A. (2012). Time intervals to assess active and capable faults for engineering practices in Italy. Eng. Geol., 139/140, 50-65.
The Core-Collapse Supernova-Black Hole Connection

NASA Astrophysics Data System (ADS)

O'Connor, Evan

The death of a massive star is typically associated with a bright optical transient known as a core-collapse supernova. However, there is growing evidence that not all massive stars end their lives with a brillant optical display, but rather in a whimper. These failed supernovae, or unnovae, result from the central engine failing to turn the initial implosion of the iron core into an explosion that launches the supernova shock wave, unbinds the majority of the star, and creates the supernova as we know it. In these unnovae, the failure of the central engine is soon followed by the collapse of the would-be neutron star into a stellar mass black hole. Instead of the bright optical display following successful supernovae, little to no optical emission is expected from typical failed supernovae as most of the material quietly accretes onto the black hole. This makes the hunt for failed supernovae difficult. In this chapter for the Handbook of Supernovae, I present the growing observational evidence for failed supernovae and discuss the current theoretical understanding of how and in what stars the supernova central engine fails.
Monitoring Mitochondrial Pyruvate Carrier Activity in Real Time Using a BRET-Based Biosensor: Investigation of the Warburg Effect.

PubMed

Compan, Vincent; Pierredon, Sandra; Vanderperre, Benoît; Krznar, Petra; Marchiq, Ibtissam; Zamboni, Nicola; Pouyssegur, Jacques; Martinou, Jean-Claude

2015-08-06

The transport of pyruvate into mitochondria requires a specific carrier, the mitochondrial pyruvate carrier (MPC). The MPC represents a central node of carbon metabolism, and its activity is likely to play a key role in bioenergetics. Until now, investigation of the MPC activity has been limited. However, the recent molecular identification of the components of the carrier has allowed us to engineer a genetically encoded biosensor and to monitor the activity of the MPC in real time in a cell population or in a single cell. We report that the MPC activity is low in cancer cells, which mainly rely on glycolysis to generate ATP, a characteristic known as the Warburg effect. We show that this low activity can be reversed by increasing the concentration of cytosolic pyruvate, thus increasing oxidative phosphorylation. This biosensor represents a unique tool to investigate carbon metabolism and bioenergetics in various cell types. Copyright © 2015 Elsevier Inc. All rights reserved.
Cell painting with an engineered EPCR to augment the protein C system.

PubMed

Bouwens, Eveline A M; Stavenuiter, Fabian; Mosnier, Laurent O

2015-11-25

The protein C (PC) system conveys beneficial anticoagulant and cytoprotective effects in numerous in vivo disease models. The endothelial protein C receptor (EPCR) plays a central role in these pathways as cofactor for PC activation and by enhancing activated protein C (APC)-mediated protease-activated receptor (PAR) activation. During inflammatory disease, expression of EPCR on cell membranes is often diminished thereby limiting PC activation and APC's effects on cells. Here a caveolae-targeting glycosylphosphatidylinositol (GPI)-anchored EPCR (EPCR-GPI) was engineered to restore EPCR's bioavailability via "cell painting." The painting efficiency of EPCR-GPI on EPCR-depleted endothelial cells was time- and dose-dependent. The EPCR-GPI bioavailability after painting was long lasting since EPCR surface levels reached 400 % of wild-type cells after 2 hours and remained > 200 % for 24 hours. EPCR-GPI painting conveyed APC binding to EPCR-depleted endothelial cells where EPCR was lost due to shedding or shRNA. EPCR painting normalised PC activation on EPCR-depleted cells indicating that EPCR-GPI is functional active on painted cells. Caveolin-1 lipid rafts were enriched in EPCR after painting due to the GPI-anchor targeting caveolae. Accordingly, EPCR painting supported PAR1 and PAR3 cleavage by APC and augmented PAR1-dependent Akt phosphorylation by APC. Thus, EPCR-GPI painting achieved physiological relevant surface levels on endothelial cells, restored APC binding to EPCR-depleted cells, supported PC activation, and enhanced APC-mediated PAR cleavage and cytoprotective signalling. Therefore, EPCR-GPI provides a novel tool to restore the bioavailability and functionality of EPCR on EPCR- depleted and -deficient cells.
Stability Analysis of Distributed Engine Control Systems Under Communication Packet Drop (Postprint)

DTIC Science & Technology

2008-07-01

use, modify, reproduce, release, perform, display, or disclose the work. 14. ABSTRACT Currently, Full Authority Digital Engine Control ( FADEC ...based on a centralized architecture framework is being widely used for gas turbine engine control. However, current FADEC is not able to meet the...system (DEC). FADEC based on Distributed Control Systems (DCS) offers modularity, improved control systems prognostics and fault tolerance along with
Human Body Interfacing.

ERIC Educational Resources Information Center

Fryda, Lawrence J.; Harrington, Robert; Szumal, Clint

Electronics Engineering Technology majors in the Industrial and Engineering Technology department at Central Michigan University have developed many real-world projects that represent the type of problem-solving projects encouraged by industry. Two projects that can be used by other educators as freestanding projects or as the core for further…
Engineering the Big Chill: The story of JLab’s Central Helium Liquefier

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

Westfall, Catherine

This article tells the story of the Central Helium Liquefier (CHL) at the Thomas Jefferson National Accelerator Facility (JLab), one of the US National Laboratories. JLab’s successful superconducting radio frequency accelerator was only possible because a group of JLab engineers successfully tackled a complex of difficulties to build a cryogenic system that included the CHL, a task that required advancing the frontier of cryogenic technology. Ultimately, these cryogenic advances were applied far beyond JLab to the benefit of cutting-edge programs at other US national laboratories (Oak Ridge, Brookhaven, and the Facility for Rare Isotope Beams at MSU) as well asmore » NASA. In addition, this innovation story dramatizes the sort of engineer-driven technological problem solving that allows the successful launch and operation of experimental projects. Along the way, the CHL story also provides an important addition to our understanding of the role played by engineers and industry in creating knowledge at physics laboratories.« less
Engineering the Big Chill: The story of JLab’s Central Helium Liquefier

DOE PAGES

Westfall, Catherine

2014-03-29

This article tells the story of the Central Helium Liquefier (CHL) at the Thomas Jefferson National Accelerator Facility (JLab), one of the US National Laboratories. JLab’s successful superconducting radio frequency accelerator was only possible because a group of JLab engineers successfully tackled a complex of difficulties to build a cryogenic system that included the CHL, a task that required advancing the frontier of cryogenic technology. Ultimately, these cryogenic advances were applied far beyond JLab to the benefit of cutting-edge programs at other US national laboratories (Oak Ridge, Brookhaven, and the Facility for Rare Isotope Beams at MSU) as well asmore » NASA. In addition, this innovation story dramatizes the sort of engineer-driven technological problem solving that allows the successful launch and operation of experimental projects. Along the way, the CHL story also provides an important addition to our understanding of the role played by engineers and industry in creating knowledge at physics laboratories.« less
Supporting productive thinking: The semiotic context for Cognitive Systems Engineering (CSE).

PubMed

Flach, John

2017-03-01

The central thesis of this paper is that Rasmussen framed his approach to Cognitive Systems Engineering from the perspective of a Triadic Semiotic Model. This frame became the context for integrating multiple intellectual threads including Control Theory, Information Theory, Ecological Psychology, and Gestalt Psychology into a coherent theoretical framework. The case is made that the triadic semiotic framework is essential for a complete appreciation of the constructs that were central to Rasmussen's approach: Abstraction Hierarchy, Skill-Rules-Knowledge Model, Ecological Interface Design, and Proactive Risk Management. Copyright © 2015 Elsevier Ltd. All rights reserved.
TALEN-engineered AR gene rearrangements reveal endocrine uncoupling of androgen receptor in prostate cancer

PubMed Central

Nyquist, Michael D.; Li, Yingming; Hwang, Tae Hyun; Manlove, Luke S.; Vessella, Robert L.; Silverstein, Kevin A. T.; Voytas, Daniel F.; Dehm, Scott M.

2013-01-01

Androgen receptor (AR) target genes direct development and survival of the prostate epithelial lineage, including prostate cancer (PCa). Thus, endocrine therapies that inhibit the AR ligand-binding domain (LBD) are effective in treating PCa. AR transcriptional reactivation is central to resistance, as evidenced by the efficacy of AR retargeting in castration-resistant PCa (CRPC) with next-generation endocrine therapies abiraterone and enzalutamide. However, resistance to abiraterone and enzalutamide limits this efficacy in most men, and PCa remains the second-leading cause of male cancer deaths. Here we show that AR gene rearrangements in CRPC tissues underlie a completely androgen-independent, yet AR-dependent, resistance mechanism. We discovered intragenic AR gene rearrangements in CRPC tissues, which we modeled using transcription activator-like effector nuclease (TALEN)-mediated genome engineering. This modeling revealed that these AR gene rearrangements blocked full-length AR synthesis, but promoted expression of truncated AR variant proteins lacking the AR ligand-binding domain. Furthermore, these AR variant proteins maintained the constitutive activity of the AR transcriptional program and a CRPC growth phenotype independent of full-length AR or androgens. These findings demonstrate that AR gene rearrangements are a unique resistance mechanism by which AR transcriptional activity can be uncoupled from endocrine regulation in CRPC. PMID:24101480
75 FR 17703 - Combined Notice of Filings # 1

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-07

...: Southwest Power Pool, Inc submits Substitute Sixth Revised Sheet 14 et al to its FERC Electric Tariff, Fifth...: Central Maine Power Company. Description: Central Maine Power Company submits Engineering and Procurement.... Docket Numbers: ER10-911-001. Applicants: Wisconsin Electric Power Company. Description: Wisconsin...
Research on shock wave characteristics in the isolator of central strut rocket-based combined cycle engine under Ma5.5

NASA Astrophysics Data System (ADS)

Wei, Xianggeng; Xue, Rui; Qin, Fei; Hu, Chunbo; He, Guoqiang

2017-11-01

A numerical calculation of shock wave characteristics in the isolator of central strut rocket-based combined cycle (RBCC) engine fueled by kerosene was carried out in this paper. A 3D numerical model was established by the DES method. The kerosene chemical kinetic model used the 9-component and 12-step simplified mechanism model. Effects of fuel equivalence ratio, inflow total temperature and central strut rocket on-off on shock wave characteristics were studied under Ma5.5. Results demonstrated that with the increase of equivalence ratio, the leading shock wave moves toward upstream, accompanied with higher possibility of the inlet unstart. However, the leading shock wave moves toward downstream as the inflow total temperature rises. After the central strut rocket is closed, the leading shock wave moves toward downstream, which can reduce risks of the inlet unstart. State of the shear layer formed by the strut rocket jet flow and inflow can influence the shock train structure significantly.
Seeing through the lens of social justice: A threshold for engineering

NASA Astrophysics Data System (ADS)

Kabo, Jens David

In recent times the need for educational research dedicated to engineering education has been recognised. This PhD project is a contribution to the development of engineering education scholarship and the growing body of engineering education research. In this project it was recognised that problem solving is a central activity to engineering. However, it was also recognised that the conditions for doing engineering are changing, especially in light of pressing issues of poverty and environmental sustainability that humanity currently faces, and as a consequence, engineering education needs to emphasise problem definition to a greater extent. One mechanism for achieving this, which has been adopted by some engineering educators in recent years, is through courses that explicitly relate engineering to social justice. However, creating this relationship requires critical interdisciplinary thinking that is alien to most engineering students. In this dissertation it is suggested that for engineering students, and more generally, engineers, looking at their practice and profession through a social justice lens might be seen as a threshold that needs to be crossed. By studying the variation present among students in three different courses at three different North American universities, the intention was to understand how students approach and internalise social justice as a perspective on engineering and/or develop their abilities to think critically. A conceptual model to frame the study was developed by combining elements of threshold concept theory and the educational research methodology, phenomenographic variation theory. All three of the courses studied operated on a similar basic pedagogical model, however, the courses were framed differently, with social justice in the foreground or in the background with the focus on, in one case, ethics and in the other, sustainability. All courses studied appeared to be successful in encouraging engineering students to engage in critical thinking and a similar general trend in the development of students' conceptions of social justice was observed in each of the three courses. However, it does appear that if one is interested in developing an articulated understanding of social justice, with respect to engineering, that an explicit focus on social justice is preferable.
Engine Lubricant

NASA Technical Reports Server (NTRS)

1993-01-01

PS 212, a plasma-sprayed coating developed by NASA, is used to coat valves in a new rotorcam engine. The coating eliminates the need for a liquid lubricant in the rotorcam, which has no crankshaft, flywheel, distributor or water pump. Developed by Murray United Development Corporation, it is a rotary engine only 10 inches long with four cylinders radiating outward from a central axle. Company officials say the engine will be lighter, more compact and cheaper to manufacture than current engines and will feature cleaner exhaust emissions. A licensing arrangement with a manufacturer is under negotiation. Primary applications are for automobiles, but the engine may also be used in light aircraft.
Spatially resolved metabolic analysis reveals a central role for transcriptional control in carbon allocation to wood.

PubMed

Roach, Melissa; Arrivault, Stéphanie; Mahboubi, Amir; Krohn, Nicole; Sulpice, Ronan; Stitt, Mark; Niittylä, Totte

2017-06-15

The contribution of transcriptional and post-transcriptional regulation to modifying carbon allocation to developing wood of trees is not well defined. To clarify the role of transcriptional regulation, the enzyme activity patterns of eight central primary metabolism enzymes across phloem, cambium, and developing wood of aspen (Populus tremula L.) were compared with transcript levels obtained by RNA sequencing of sequential stem sections from the same trees. Enzymes were selected on the basis of their importance in sugar metabolism and in linking primary metabolism to lignin biosynthesis. Existing enzyme assays were adapted to allow measurements from ~1 mm3 sections of dissected stem tissue. These experiments provided high spatial resolution of enzyme activity changes across different stages of wood development, and identified the gene transcripts probably responsible for these changes. In most cases, there was a clear positive relationship between transcripts and enzyme activity. During secondary cell wall formation, the increases in transcript levels and enzyme activities also matched with increased levels of glucose, fructose, hexose phosphates, and UDP-glucose, emphasizing an important role for transcriptional regulation in carbon allocation to developing aspen wood. These observations corroborate the efforts to increase carbon allocation to wood by engineering gene regulatory networks. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.
78 FR 36538 - 36(b)(1) Arms Sales Notification

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-18

... training equipment, U.S. Government and contractor engineering, technical and logistics support services... equipment, U.S. Government and contractor engineering, technical and logistics support services, and other... central government and the country's outlying areas. The sale of these C-130Js to Libya will significantly...
ENGINEERING DESIGN CRITERIA FOR SUB-SLAB DEPRESSURIZATION SYSTEMS IN LOW-PERMEABILTY SOLIDS

EPA Science Inventory

The report describes the development of engineering design criteria for the successful design, installation, and operation of sub-slab depressurization systems, based on radon (Rn) mitigation experience on 14 slab-on-grade houses in South Central Florida. The Florida houses are c...
Suitability of soil bioengineering techniques in Central America: a case study in Nicaragua

NASA Astrophysics Data System (ADS)

Petrone, A.; Preti, F.

2008-02-01

In the last few years "D. I. A. F." (Department of Agriculture and Forestry Engineering of Florence University), has been testing the effectiveness of Soil Bio-Engineering techniques in Central America. The focus of the present study was to find out which native plants were most suited for soil bio-engineering purposes, particularly in the realization of riverbank protection. Furthermore, we have also been aiming at economic efficiency. In the context of sustainable watershed management, these techniques seem to be appropriate, especially in underdeveloped countries. Concerning the plants to be used, we considered three native species, Gliricidia Sepium, Cordia dentata and Jatropha curcas, to be appropriate for this type of work. Economically speaking, the low cost of such interventions in underdeveloped countries, has been shown by the construction of riverbank protection using vegetated crib-walls in Nicaragua.

Distributed Control of Turbofan Engines

DTIC Science & Technology

2009-08-01

performance of the engine. Thus the Full Authority Digital Engine Controller ( FADEC ) still remains the central arbiter of the engine’s dynamic behavior...instance, if the control laws are not distributed the dependence on the FADEC remains high, and system reliability can only be insured through many...if distributed computing is used at the local level and only coordinated by the FADEC . Such an architecture must be studied in the context of noisy
Modeling quasar central engine as a relativistic radiating star

NASA Astrophysics Data System (ADS)

Singh, Ksh. Newton; Pant, Neeraj

2015-01-01

Long ago Hoyle & Fowler attempted to model the central engine of quasars as hot super-massive stars supported by radiation pressure. Whereas the model of Hoyle & Fowler was Newtonian, here we make a toy model of quasar central engines as ultra relativistic ultrahot plasma or as a ball of radiation. Accordingly, we consider general relativistic gravitational collapse including emission of radiation. More specifically, we discuss a new class of radiating fluid ball exact solution in conformally-flat metric which is quasi-static and contracting at negligible rate. The problem is solved by assuming that the metric potential is separable in to radial and time dependent parts. It is found the gravitational mass of the radiating ball M→0 as comoving time t→∞ in conformity of the idea of an "Eternally Collapsing Object" (ECO) which has been claimed to be the true nature of the so-called "Black Holes". In particular, we consider here a quasi-static radiation ball having M≈9.507×107 M ⊙, a radius of ≈2×1014 km, and a luminosity L ∞≈9.1×1046 erg/s. Prima-facie, such an ECO solution is compatible with the central compact object of a quasar having comoving lifetime of ≈107 yr and a distantly observed lifetime ( u) which could be higher by many orders of magnitude.
The role of low levels of fullerene C60 nanocrystals on enhanced learning and memory of rats through persistent CaMKII activation.

PubMed

Chen, Liang; Miao, Yanyan; Chen, Lin; Xu, Jing; Wang, Xinxing; Zhao, Han; Shen, Yi; Hu, Yi; Bian, Yunpeng; Shen, Yuanyuan; Chen, Jutao; Zha, Yingying; Wen, Long-Ping; Wang, Ming

2014-11-01

Engineered nanomaterials are known to exhibit diverse and sometimes unexpected biological effects. Fullerene nanoparticles have been reported to specifically bind to and elicit persistent activation of hippocampal Ca(2+)/calmodulin-dependent protein kinase II (CaMKII), a multimeric intracellular serine/threonine kinase central to Ca(2+) signal transduction and critical for synaptic plasticity, but the functional consequence of that modulation is unknown. Here we show that low doses of fullerene C60 nanocrystals (Nano C60), delivered through intrahippocampal infusion and without any obvious cytotoxicity in hippocampal neuronal cells, enhance the long-term potentiation (LTP) of rats. Intraperitoneal injection of 320 μg/kg of Nano C60, once daily for 10 days, also enhanced spatial memory of rats in addition to an increase of LTP. In parallel, both the IH and IP administration of Nano C60 increased the autonomous activity and the level of threonine 286 (T286) autophosphorylation of CaMKII, enhanced post-synaptic AMPA/NMDA ratio, and triggered time-dependent activation of ERK and CREB. Our results reveal a striking and highly unexpected ability of Nano C60 in positively modulating learning and memory, an effect that is most likely manifested through locking CaMKII in an active conformation, and may have significant implications for the potential therapeutic applications of fullerene C60, a classic engineered nanomaterial. Copyright © 2014 Elsevier Ltd. All rights reserved.
Solvent-driven reductive activation of carbon dioxide by gold anions.

PubMed

Knurr, Benjamin J; Weber, J Mathias

2012-11-14

Catalytic activation and electrochemical reduction of CO(2) for the formation of chemically usable feedstock and fuel are central goals for establishing a carbon neutral fuel cycle. The role of solvent molecules in catalytic processes is little understood, although solvent-solute interactions can strongly influence activated intermediate species. We use vibrational spectroscopy of mass-selected Au(CO(2))(n)(-) cluster ions to probe the solvation of AuCO(2)(-) as a model for a reactive intermediate in the reductive activation of a CO(2) ligand by a single-atom catalyst. For the first few solvent molecules, solvation of the complex preferentially occurs at the CO(2) moiety, enhancing reductive activation through polarization of the excess charge onto the partially reduced ligand. At higher levels of solvation, direct interaction of additional solvent molecules with the Au atom diminishes reduction. The results show how the solvation environment can enhance or diminish the effects of a catalyst, offering design criteria for single-atom catalyst engineering.
The experiences of female high school students and interest in STEM: Factors leading to the selection of an engineering or computer science major

NASA Astrophysics Data System (ADS)

Genoways, Sharon K.

STEM (Science, Technology, Engineering and Math) education creates critical thinkers, increases science literacy, and enables the next generation of innovators, which leads to new products and processes that sustain our economy (Hossain & Robinson, 2012). We have been hearing the warnings for several years, that there simply are not enough young scientists entering into the STEM professional pathways to replace all of the retiring professionals (Brown, Brown, Reardon, & Merrill, 2011; Harsh, Maltese, & Tai, 2012; Heilbronner, 2011; Scott, 2012). The problem is not necessarily due to a lack of STEM skills and concept proficiency. There also appears to be a lack of interest in these fields. Recent evidence suggests that many of the most proficient students, especially minority students and women, have been gravitating away from science and engineering toward other professions. (President's Council of Advisors on Science and Technology, 2010). The purpose of this qualitative research study was an attempt to determine how high schools can best prepare and encourage young women for a career in engineering or computer science. This was accomplished by interviewing a pool of 21 women, 5 recent high school graduates planning to major in STEM, 5 college students who had completed at least one full year of coursework in an engineering or computer science major and 11 professional women who had been employed as an engineer or computer scientist for at least one full year. These women were asked to share the high school courses, activities, and experiences that best prepared them to pursue an engineering or computer science major. Five central themes emerged from this study; coursework in physics and calculus, promotion of STEM camps and clubs, teacher encouragement of STEM capabilities and careers, problem solving, critical thinking and confidence building activities in the classroom, and allowing students the opportunity to fail and ask questions in a safe environment. These themes may be implemented by any instructor, in any course, who wishes to provide students with the means to success in their quest for a STEM career.
40 CFR 86.1542 - Information required.

Code of Federal Regulations, 2011 CFR

2011-07-01

... required: (1) Date and time of day. (2) Test number. (3) Engine intake air or test cell temperature. (4) Barometric pressure. Note: A central laboratory barometer may be used: Provided, That individual test cell... location. (5) Engine intake or test cell and CVS dilution air humidity. (6) Curb idle speed during the test...
40 CFR 86.1542 - Information required.

Code of Federal Regulations, 2012 CFR

2012-07-01

... required: (1) Date and time of day. (2) Test number. (3) Engine intake air or test cell temperature. (4) Barometric pressure. Note: A central laboratory barometer may be used: Provided, That individual test cell... location. (5) Engine intake or test cell and CVS dilution air humidity. (6) Curb idle speed during the test...
48 CFR Appendix A to Part 1219 - Appendix A to Part 1219

Code of Federal Regulations, 2014 CFR

2014-10-01

... Rebuilding of engines, turbines, components and weapons equipment J028/J010 (5) ADP Central Processing Units... Engines, Aircraft; and Components 2840 (10) Radar Equipment (except airborne) and Navigation and Navigational Aids (basic research) 5840/AT31 * The industry categories were derived from Federal Procurement...
48 CFR Appendix A to Part 1219 - Appendix A to Part 1219

Code of Federal Regulations, 2012 CFR

2012-10-01

... Rebuilding of engines, turbines, components and weapons equipment J028/J010 (5) ADP Central Processing Units... Engines, Aircraft; and Components 2840 (10) Radar Equipment (except airborne) and Navigation and Navigational Aids (basic research) 5840/AT31 * The industry categories were derived from Federal Procurement...
48 CFR Appendix A to Part 1219 - Appendix A to Part 1219

Code of Federal Regulations, 2013 CFR

2013-10-01

... Rebuilding of engines, turbines, components and weapons equipment J028/J010 (5) ADP Central Processing Units... Engines, Aircraft; and Components 2840 (10) Radar Equipment (except airborne) and Navigation and Navigational Aids (basic research) 5840/AT31 * The industry categories were derived from Federal Procurement...
48 CFR Appendix A to Part 1219 - Appendix A to Part 1219

Code of Federal Regulations, 2011 CFR

2011-10-01

... Rebuilding of engines, turbines, components and weapons equipment J028/J010 (5) ADP Central Processing Units... Engines, Aircraft; and Components 2840 (10) Radar Equipment (except airborne) and Navigation and Navigational Aids (basic research) 5840/AT31 * The industry categories were derived from Federal Procurement...
Engineering at the Elementary Level

ERIC Educational Resources Information Center

McGrew, Cheryl

2012-01-01

Can engineering technology be taught at the elementary level? Designing and building trebuchets, catapults, solar cars, and mousetrap vehicles in a west central Florida elementary class was considered very unusual in recent years. After a review of current research on failing schools and poor curriculum, the author wondered what her school could…
Biotechnology Process Engineering Center at MIT - Overview

Science.gov Websites

laboratories. Biotechnology-related research in the labs of over 15 faculty members in the Biological 60,000 square feet for biotechnology-related engineering research. This centralization and consolidation wider array of equipment and facilities available in other MIT labs and Centers. Some examples include
A DIRECTORY OF INFORMATION RESOURCES IN THE UNITED STATES. PHYSICAL SCIENCES, BIOLOGICAL SCIENCES, ENGINEERING.

ERIC Educational Resources Information Center

Library of Congress, Washington, DC.

SOURCES OF INFORMATION FOR BIOLOGICAL AND PHYSICAL SCIENCE AND ENGINEERING ARE LISTED. THEY INCLUDE--(1) LIBRARIES, (2) CENTRALIZED INFORMATION CENTERS, (3) PROFESSIONAL SOCIETIES AND OTHER SPECIALIZING ORGANIZATIONS, (4) INDUSTRIAL FIRMS, (5) GOVERNMENTAL AGENCIES OR OFFICES, AND (6) OTHER INFORMATION SOURCES WHICH MAKE SCIENTIFIC AND…
Exploring Agricultural and Biotechnical Engineering through Hands-On Integrated STEM

ERIC Educational Resources Information Center

Preble, Brian C.

2015-01-01

The manipulation of the natural world in the form of plant materials to design, control, and grow desirable agricultural commodities was central to the establishment and advancement of civilization. Modern developments in genetically modified organisms (GMOs or biologically engineered foods) can trace their origins to macro practices developed and…
Ethnographic Evaluation of the MESA Program at a South-Central Phoenix High School.

ERIC Educational Resources Information Center

Jaramillo, James A.

MESA (Mathematics, Engineering, and Science Achievement) is a program designed to increase the number of underrepresented ethnic groups in professions related to mathematics, engineering, and the physical sciences. This paper describes and evaluates the MESA program at Jarama High School, Phoenix (Arizona), using informal interviews and…
Progress in industrial holography in France

NASA Astrophysics Data System (ADS)

Smigielski, Paul

1992-01-01

Industrial applications of holography in France are briefly reviewed. Particular attention is given to nondestructive testing of helicopter blades at Aerospatiale Central Laboratory, the use of holography at Renault for car-engine vibration study, vibration characterization of turbo-jet engine components at SNECMA, and vibration analysis of plates in an industrial hemodynamic tunnel.
16. VIEW OF THE STATIONARY OPERATING ENGINEER CONTROL PANEL INSTALLATION. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. VIEW OF THE STATIONARY OPERATING ENGINEER CONTROL PANEL INSTALLATION. THE PANEL CONTROLS AIR-HANDLING EQUIPMENT AND AIR PRESSURE WITHIN THE BUILDING. (10/6/69) - Rocky Flats Plant, Plutonium Manufacturing Facility, North-central section of Plant, just south of Building 776/777, Golden, Jefferson County, CO
A Growth-rate Indicator for Compton-thick Active Galactic Nuclei

NASA Astrophysics Data System (ADS)

Brightman, M.; Masini, A.; Ballantyne, D. R.; Baloković, M.; Brandt, W. N.; Chen, C.-T.; Comastri, A.; Farrah, D.; Gandhi, P.; Harrison, F. A.; Ricci, C.; Stern, D.; Walton, D. J.

2016-07-01

Due to their heavily obscured central engines, the growth rate of Compton-thick (CT) active galactic nuclei (AGNs) is difficult to measure. A statistically significant correlation between the Eddington ratio, λ Edd, and the X-ray power-law index, Γ, observed in unobscured AGNs offers an estimate of their growth rate from X-ray spectroscopy (albeit with large scatter). However, since X-rays undergo reprocessing by Compton scattering and photoelectric absorption when the line of sight to the central engine is heavily obscured, the recovery of the intrinsic Γ is challenging. Here we study a sample of local, predominantly CT megamaser AGNs, where the black hole mass, and thus Eddington luminosity, are well known. We compile results of the X-ray spectral fitting of these sources with sensitive high-energy (E > 10 keV) NuSTAR data, where X-ray torus models, which take into account the reprocessing effects have been used to recover the intrinsic Γ values and X-ray luminosities, L X. With a simple bolometric correction to L X to calculate λ Edd, we find a statistically significant correlation between Γ and λ Edd (p = 0.007). A linear fit to the data yields Γ = (0.41 ± 0.18)log10 λ Edd + (2.38 ± 0.20), which is statistically consistent with results for unobscured AGNs. This result implies that torus modeling successfully recovers the intrinsic AGN parameters. Since the megamasers have low-mass black holes (M BH ≈ 106-107 M ⊙) and are highly inclined, our results extend the Γ-λ Edd relationship to lower masses and argue against strong orientation effects in the corona, in support of AGN unification. Finally this result supports the use of Γ as a growth-rate indicator for accreting black holes, even for CT AGNs.
Probing the central engine and environment of AGN using ARIES 1.3-m and 3.6-m telescopes

NASA Astrophysics Data System (ADS)

Chand, Hum; Rakshit, Suvendu; Jalan, Priyanka; Ojha, Vineet; Srianand, Raghunathan; Vivek, Mariappan; Mishra, Sapna; Omar, Amitesh; Kumar, Parveen; Joshi, Ravi; Gopal-Krishna; Kumar, Rathna

2018-04-01

We discuss three long term observational programmes to probe the central engine and environment of active galactic nuclei (AGN) using the recently installed ARIES 1.3-m and 3.6-m telescopes. The first programme is on the photometric reverberation mapping of low luminosity AGN by mainly using the ARIES 1.3-m telescope. The major impact of this programme other than to estimate the black hole mass will be to extend the broad line region (BLR) radius-luminosity (RBLR-LAGN) relation to the unexplored low luminosity regime, and to constrain the AGN broad line region geometry. The second programme is to use long slit spectroscopy on the ARIES 3.6-m telescope to discover new high redshift quasar pairs with angular separation less than 1-arcmin. Here, the background QSOs sight-line will be used to probe the environment of the foreground QSOs at kpc-Mpc scales. The major impact of this programme will be on the discovery of new pairs which have been missed in the SDSS survey due to fiber collision below 1-arcmin separation, and use them to understand about any excess overdensity around the QSO, any anisotropic emission of QSOs, and/or any episodic activity of QSOs. The third programme is related to spectral variability studies of the C IV broad absorption line (BAL) QSOs, based on low resolution spectroscopy using the ARIES 3.6-m telescope. Here, those most interesting cases will be monitored, where the BAL flow emerges afresh or disappears completely in the C IV trough of BAL QSOs sample as seen in SDSS multi-epoch observations. Continuous monitoring of such a sample will be important for our understanding of the nature and origin of the flow, along with their stability and dynamical evolution.

Lissajous figures: an engineering tool for root cause analysis of individual cases--a preliminary concept.

PubMed

Palmer, Kenneth; Ridgway, Tim; Al-Rawi, Omar; Johnson, Ian; Poullis, Michael

2011-09-01

Some patients have short intensive care stay periods and little or no organ dysfunction after cardiac surgery and others do not despite seemingly faultless surgery, perfusion, and anesthesia. These "unknown" reasons for death and morbidity usually relate to organ ischemia and inflammation, but are obviously mutlifactorial. A Lissajous figure is a technique in electrical engineering to compare two different electrical signals. We utilize this basic concept in a very simple manner to potentially identify why some of these unknown deaths or morbidities occur. Utilizing an electronic perfusion database, we retrospectively analyzed 43 patients undergoing aortic surgery with regard to central venous saturations during cooling and rewarming. Isolated aortic valve replacement patients were excluded. Central venous saturation, time, and temperature were plotted to create a Lissajous figure for the whole operation, and during cooling and rewarming separately. Temperature and saturations were analyzed every 20 seconds. Perfusion related variables were registered and uploaded to www.perfsort.net. Lissajous figures during cooling add little to patient care due to their similarity. Isolated rewarming revealed startling differences. It is immediately visually obvious who had short and long periods of tissue ischemia and reperfusion during rewarming in a seemingly uneventful operation. The periods of ischemia can be semi quantified into: none, mild, moderate, and severe. Creation of simple Lissajous figures during rewarming for bypass runs may be an additional helpful tool in root cause analysis of patient death/morbidity when surgery, perfusion, and anesthesia seemed faultless. Low central venous saturations at hypothermic temperatures mean significant metabolic activity, indicating tissue ischemia is occurring. Further work is needed to correlate this concept to outcomes.
Fueling the AGN

NASA Astrophysics Data System (ADS)

Combes, F.

Active Galactic Nuclei are fueled from material (gas or stars) that are in general far away from the gravitational influence of the central black hole, the engine thought to be responsible for their activity. The required material has a lot of angular momentum that, a priori, is quite difficult to evacuate. The various dynamical mechanisms that may play a role in this game are reviewed, including m = 2 perturbations (bars and spirals), m = 1 perturbations (spirals, warps, lopsidedness), and tidal interactions between galaxies and mergers. In the latest stages of the merger, a binary black hole could be formed, and its influence on the dynamics and fueling is discussed. Starbursts are often associated with AGN, and the nature of their particular connection, and their role in the nuclear fueling is described. Evolution of the fueling efficiency with redshift is addressed.
Photo-oxidation of tyrosine in a bio-engineered bacterioferritin 'reaction centre'-a protein model for artificial photosynthesis.

PubMed

Hingorani, Kastoori; Pace, Ron; Whitney, Spencer; Murray, James W; Smith, Paul; Cheah, Mun Hon; Wydrzynski, Tom; Hillier, Warwick

2014-10-01

The photosynthetic reaction centre (RC) is central to the conversion of solar energy into chemical energy and is a model for bio-mimetic engineering approaches to this end. We describe bio-engineering of a Photosystem II (PSII) RC inspired peptide model, building on our earlier studies. A non-photosynthetic haem containing bacterioferritin (BFR) from Escherichia coli that expresses as a homodimer was used as a protein scaffold, incorporating redox-active cofactors mimicking those of PSII. Desirable properties include: a di-nuclear metal binding site which provides ligands for bivalent metals, a hydrophobic pocket at the dimer interface which can bind a photosensitive porphyrin and presence of tyrosine residues proximal to the bound cofactors, which can be utilised as efficient electron-tunnelling intermediates. Light-induced electron transfer from proximal tyrosine residues to the photo-oxidised ZnCe6(•+), in the modified BFR reconstituted with both ZnCe6 and Mn(II), is presented. Three site-specific tyrosine variants (Y25F, Y58F and Y45F) were made to localise the redox-active tyrosine in the engineered system. The results indicate that: presence of bound Mn(II) is necessary to observe tyrosine oxidation in all BFR variants; Y45 the most important tyrosine as an immediate electron donor to the oxidised ZnCe6(•+) and that Y25 and Y58 are both redox-active in this system, but appear to function interchangebaly. High-resolution (2.1Å) crystal structures of the tyrosine variants show that there are no mutation-induced effects on the overall 3-D structure of the protein. Small effects are observed in the Y45F variant. Here, the BFR-RC represents a protein model for artificial photosynthesis. Crown Copyright © 2014. Published by Elsevier B.V. All rights reserved.
Program For Engineering Electrical Connections

NASA Technical Reports Server (NTRS)

Billitti, Joseph W.

1990-01-01

DFACS is interactive multiuser computer-aided-engineering software tool for system-level electrical integration and cabling engineering. Purpose of program to provide engineering community with centralized data base for putting in and gaining access to data on functional definition of system, details of end-circuit pinouts in systems and subsystems, and data on wiring harnesses. Objective, to provide instantaneous single point of interchange of information, thus avoiding error-prone, time-consuming, and costly shuttling of data along multiple paths. Designed to operate on DEC VAX mini or micro computer using Version 5.0/03 of INGRES.
Space shuttle main engine controller

NASA Technical Reports Server (NTRS)

Mattox, R. M.; White, J. B.

1981-01-01

A technical description of the space shuttle main engine controller, which provides engine checkout prior to launch, engine control and monitoring during launch, and engine safety and monitoring in orbit, is presented. Each of the major controller subassemblies, the central processing unit, the computer interface electronics, the input electronics, the output electronics, and the power supplies are described and discussed in detail along with engine and orbiter interfaces and operational requirements. The controller represents a unique application of digital concepts, techniques, and technology in monitoring, managing, and controlling a high performance rocket engine propulsion system. The operational requirements placed on the controller, the extremely harsh operating environment to which it is exposed, and the reliability demanded, result in the most complex and rugged digital system ever designed, fabricated, and flown.
ACCELERATION OF COMPACT RADIO JETS ON SUB-PARSEC SCALES

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

Lee, Sang-Sung; Lobanov, Andrei P.; Krichbaum, Thomas P.

2016-08-01

Jets of compact radio sources are highly relativistic and Doppler boosted, making studies of their intrinsic properties difficult. Observed brightness temperatures can be used to study the intrinsic physical properties of relativistic jets, and constrain models of jet formation in the inner jet region. We aim to observationally test such inner jet models. The very long baseline interferometry (VLBI) cores of compact radio sources are optically thick at a given frequency. The distance of the core from the central engine is inversely proportional to the frequency. Under the equipartition condition between the magnetic field energy and particle energy densities, themore » absolute distance of the VLBI core can be predicted. We compiled the brightness temperatures of VLBI cores at various radio frequencies of 2, 8, 15, and 86 GHz. We derive the brightness temperature on sub-parsec scales in the rest frame of the compact radio sources. We find that the brightness temperature increases with increasing distance from the central engine, indicating that the intrinsic jet speed (the Lorentz factor) increases along the jet. This implies that the jets are accelerated in the (sub-)parsec regions from the central engine.« less
Implementation of partnership management model of SMK (Vocational High School) with existing industries in mechanical engineering expertise in Central Java

NASA Astrophysics Data System (ADS)

Sumbodo, Wirawan; Pardjono, Samsudi, Rahadjo, Winarno Dwi

2018-03-01

This study aims to determine the existing conditions of implementation of partnership management model of SMK with the industry on the mechanical engineering expertise in Central Java. The method used is descriptive analysis. The research result shows that the implementation of partnership management model of SMK based on new existing industry produces ready graduates of 62.5% which belongs to low category, although the partnership program of SMK with the industry is done well with the average score of 3.17. As many as 37.5% of SMK graduates of Mechanical Engineering Expertise Program choose to continue their studies or to be an entrepreneur. It is expected that the partnership model of SMK with the industry can be developed into a reference for government policy in developing SMK that is able to produce graduates who are ready to work according to the needs of partner industry.
Cell painting with an engineered EPCR to augment the protein C system

PubMed Central

Bouwens, Eveline A. M.; Stavenuiter, Fabian; Mosnier, Laurent O.

2016-01-01

The protein C (PC) system conveys beneficial anticoagulant and cytoprotective effects in numerous in vivo disease models. The endothelial protein C receptor (EPCR) plays a central role in these pathways as cofactor for PC activation and by enhancing activated protein C (APC)-mediated protease-activated receptor (PAR) activation. During inflammatory disease, expression of EPCR on cell membranes is often diminished thereby limiting PC activation and APC’s effects on cells. Here a caveolae-targeting glycosylphosphatidylinositol (GPI)-anchored EPCR (EPCR-GPI) was engineered to restore EPCR’s bioavailability via “cell painting.” The painting efficiency of EPCR-GPI on EPCR-depleted endothelial cells was time- and dose-dependent. The EPCR-GPI bioavailability after painting was long lasting since EPCR surface levels reached 400% of wild-type cells after 2 hours and remained >200% for 24 hours. EPCR-GPI painting conveyed APC binding to EPCR-depleted endothelial cells where EPCR was lost due to shedding or shRNA. EPCR painting normalized PC activation on EPCR-depleted cells indicating that EPCR-GPI is functional active on painted cells. Caveolin-1 lipid rafts were enriched in EPCR after painting due to the GPI-anchor targeting caveolae. Accordingly, EPCR painting supported PAR1 and PAR3 cleavage by APC and augmented PAR1-dependent Akt phosphorylation by APC. Thus, EPCR-GPI painting achieved physiological relevant surface levels on endothelial cells, restored APC binding to EPCR-depleted cells, supported PC activation, and enhanced APC-mediated PAR cleavage and cytoprotective signaling. Therefore, EPCR-GPI provides a novel tool to restore the bioavailability and functionality of EPCR on EPCR-depleted and deficient cells. PMID:26272345
Ground-water conditions in the central Virgin River basin, Utah

USGS Publications Warehouse

Cordova, R.M.; Sandberg, G.W.; McConkie, Wilson

1972-01-01

Water-rights problems have occurred in the central Virgin River basin and are expected to increase as development of the water resources increases. The Utah State Engineer needs a basic knowledge of ground-water conditions and of the relation of ground water to surface water as a first step to understanding and resolving the problems. Accordingly, the State Engineer requested the U. S. Geological Survey to make a ground-water investigation of the central Virgin River basin as part of the Statewide cooperative agreement with the Utah Department of Natural Resources. The investigation was begun July 1, 1968, and fieldwork was completed in August 1970. Detailed information was obtained for the principal aquifers and for recharge, movement, discharge, storage, utilization, and chemical quality of ground water. A progress report (Cordova, Sandberg, and McConkie, 1970) describes the general findings in the first year of the investigation.
Status, Vision, and Challenges of an Intelligent Distributed Engine Control Architecture

NASA Technical Reports Server (NTRS)

Behbahani, Alireza; Culley, Dennis; Garg, Sanjay; Millar, Richard; Smith, Bert; Wood, Jim; Mahoney, Tim; Quinn, Ronald; Carpenter, Sheldon; Mailander, Bill;

2007-01-01

A Distributed Engine Control Working Group (DECWG) consisting of the Department of Defense (DoD), the National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) and industry has been formed to examine the current and future requirements of propulsion engine systems. The scope of this study will include an assessment of the paradigm shift from centralized engine control architecture to an architecture based on distributed control utilizing open system standards. Included will be a description of the work begun in the 1990's, which continues today, followed by the identification of the remaining technical challenges which present barriers to on-engine distributed control.

The Development of a Concept Inventory for Engineering Graphics

ERIC Educational Resources Information Center

Nozaki, Steven Yasuto

2017-01-01

Graphics education has been a central component in the engineering course of study. As technology advances, so have the methods in which graphics are expressed and practiced. Though the of media of graphics education have evolved, the concepts of the field remain relatively consistent. Tools are needed to measure students' comprehension,…
U.S. Engineering Degrees for Improving South Indian Graduate Students' Marriage and Dowry Options

ERIC Educational Resources Information Center

Yakaboski, Tamara; Sheridan, Robyn Stout; Dade, Kristin

2014-01-01

The article examines improved marriage opportunities as an unexplored motivator for pursuing international education via U.S. graduate engineering degrees and stresses the need to centralize gender in analyzing academic mobility and international education. This interdisciplinary qualitative study explores how South Indian men and women's…
University of Maryland MRSEC - Education: Resources

Science.gov Websites

. University of Maryland Materials Research Science and Engineering Center Home About Us Leadership Moments in MSE The Materials Science and Engineering Career Resources Center Materials Research Society Central Super Science Fair Projects: Ideas, Topics, & Experiments All Science Fair Projects Science
Social Cognitive Predictors of Adjustment to Engineering Majors across Gender and Race/Ethnicity

ERIC Educational Resources Information Center

Lent, Robert W.; Miller, Matthew J.; Smith, Paige E.; Watford, Bevlee A.; Lim, Robert H.; Hui, Kayi; Morrison, M. Ashley; Wilkins, Gregory; Williams, Kevin

2013-01-01

We tested a social cognitive model of academic adjustment in a sample of 1377 students enrolled in engineering schools at two predominantly White and two historically Black state universities. The model brought together central elements of social cognitive career theory's (SCCT) segmental models of educational/vocational satisfaction, interest,…
A Self-Ethnographic Investigation of Continuing Education Program in Engineering Arising from Economic Structural Change

ERIC Educational Resources Information Center

Kaihlavirta, Auri; Isomöttönen, Ville; Kärkkäinen, Tommi

2015-01-01

This paper provides a self-ethnographic investigation of a continuing education program in engineering in Central Finland. The program was initiated as a response to local economic structural change, in order to offer re-education possibilities for a higher educated workforce currently under unemployment threat. We encountered considerable…
Evaluating Self-Efficacy Expected of Polytechnic Engineering Students as a Measure of Employability

ERIC Educational Resources Information Center

Ojonugwa, Oguche Innocent; Hamzah, Ramlah; Bakar, AB Rahim; Rashid, Abdullah Mat

2015-01-01

In the face of increasing unemployment partly due to decreasing employability skills of Nigeria polytechnic students, many graduates of Nigeria polytechnic have a dwindle self-efficacy. 420 HND 2 polytechnic engineering students in north central states of Nigeria were surveyed. Data were collected using questionnaire consisting of 4 Likert-type…
Prediction of the Thrust Performance and the Flowfield of Liquid Rocket Engines

NASA Technical Reports Server (NTRS)

Wang, T.-S.

1990-01-01

In an effort to improve the current solutions in the design and analysis of liquid propulsive engines, a computational fluid dynamics (CFD) model capable of calculating the reacting flows from the combustion chamber, through the nozzle to the external plume, was developed. The Space Shuttle Main Engine (SSME) fired at sea level, was investigated as a sample case. The CFD model, FDNS, is a pressure based, non-staggered grid, viscous/inviscid, ideal gas/real gas, reactive code. An adaptive upwinding differencing scheme is employed for the spatial discretization. The upwind scheme is based on fourth order central differencing with fourth order damping for smooth regions, and second order central differencing with second order damping for shock capturing. It is equipped with a CHMQGM equilibrium chemistry algorithm and a PARASOL finite rate chemistry algorithm using the point implicit method. The computed flow results and performance compared well with those of other standard codes and engine hot fire test data. In addition, the transient nozzle flowfield calculation was also performed to demonstrate the ability of FDNS in capturing the flow separation during the startup process.
Thermal Performance Data Services (TPDS)

NASA Technical Reports Server (NTRS)

French, Richard T.; Wright, Michael J.

2013-01-01

Initiated as a NASA Engineering and Safety Center (NESC) assessment in 2009, the Thermal Performance Database (TPDB) was a response to the need for a centralized thermal performance data archive. The assessment was renamed Thermal Performance Data Services (TPDS) in 2012; the undertaking has had two fronts of activity: the development of a repository software application and the collection of historical thermal performance data sets from dispersed sources within the thermal performance community. This assessment has delivered a foundational tool on which additional features should be built to increase efficiency, expand the protection of critical Agency investments, and provide new discipline-advancing work opportunities. This report contains the information from the assessment.
Bioengineering approaches to controlled protein delivery.

PubMed

Kobsa, Serge; Saltzman, W Mark

2008-05-01

Proteins are of crucial importance in all biologic organisms, in terms of both structure and function. Their deficits play central roles in many pathologic states, and their potential as powerful therapeutic agents has been widely recognized. Many issues, however, exist in delivery of biologically active proteins to target tissues and organs. Recent advances in biomedical engineering have lead to development of advanced techniques for controlled delivery of peptides and proteins, paving the way for their efficient use in treating human injury and disease. With a particular emphasis on most recent advances, this review discusses currently available techniques for controlled delivery of proteins and considers future research directions.
Google earth mapping of damage from the Nigata-Ken-Chuetsu M6.6 earthquake of 16 July 2007

USGS Publications Warehouse

Kayen, Robert E.; Steele, WM. Clint; Collins, Brian; Walker, Kevin

2008-01-01

We describe the use of Google Earth during and after a large damaging earthquake thatstruck the central Japan coast on 16 July 2007 to collect and organize damage information and guide the reconnaissance activities. This software enabled greater real-time collaboration among scientists and engineers. After the field investigation, the Google Earth map is used as a final reporting product that was directly linked to the more traditional research report document. Finally, we analyze the use of the software within the context of a post-disaster reconnaissance investigation, and link it to student use of GoogleEarth in field situations

Practical Modeling Concepts for Connective Tissue Stem Cell and Progenitor Compartment Kinetics

PubMed Central

2003-01-01

Stem cell activation and development is central to skeletal development, maintenance, and repair, as it is for all tissues. However, an integrated model of stem cell proliferation, differentiation, and transit between functional compartments has yet to evolve. In this paper, the authors review current concepts in stem cell biology and progenitor cell growth and differentiation kinetics in the context of bone formation. A cell-based modeling strategy is developed and offered as a tool for conceptual and quantitative exploration of the key kinetic variables and possible organizational hierarchies in bone tissue development and remodeling, as well as in tissue engineering strategies for bone repair. PMID:12975533
Phobos/Harp post launch support

NASA Technical Reports Server (NTRS)

Nagy, Andrew

1993-01-01

The activity under this grant concentrated on: (1) post-launch calibration of the HARP instrument; and (2) analysis and interpretation of the data from the HARP and other related instruments. The HARP was taken by scientists and engineers from the Hungarian Central Research Institute for Physics (CRIP) to NASA/MSFC for calibration in their plasma chamber, with partial support of this grant. This electron and ion calibration of the HARP, helped in transforming measured currents to actual flux values. The analysis and interpretation of the data, carried out jointly by our Russian and Hungarian colleagues and us, led to a number of journal publications and presentations at scientific meetings.
Research pilot Mark Pestana

NASA Image and Video Library

2001-04-16

Mark Pestana is a research pilot and project manager at the NASA Dryden Flight Research Center, Edwards, Calif. He is a pilot for the Beech B200 King Air, the T-34C and the Predator B. He flies the F-18 Hornet as a co-pilot and flight test engineer. Pestana has accumulated more than 4,000 hours of military and civilian flight experience. He was also a flight engineer on the NASA DC-8 flying laboratory. Pestana was the project manager and pilot for the Hi–rate Wireless Airborne Network Demonstration flown on the NASA B200 research aircraft. He flew B200 research missions for the X-38 Space Integrated Inertial Navigation Global Positioning System experiment. Pestana also participated in several deployments of the DC-8, including Earth science expeditions ranging from hurricane research over the Caribbean Sea to ozone studies over the North Pole, atmospheric chemistry over the South Pacific, rain forest health in Central America, Rocky Mountain ice pack assessment, and volcanic and tectonic activity around the Pacific Rim. He came to Dryden as a DC-8 mission manager in June 1998 from NASA Johnson Space Center, Houston, where he served as the Earth and Space Science discipline manager for the International Space Station Program at Johnson. Pestana also served as a flight crew operations engineer in the Astronaut Office, developing the controls, displays, tools, crew accommodations and procedures for on-orbit assembly, test, and checkout of the International Space Station. He led the analysis and technical negotiations for modification of the Russian Soyuz spacecraft as an emergency crew return vehicle for space station crews. He joined the U.S. Air Force Reserve in 1991 and held various positions as a research and development engineer, intelligence analyst, and Delta II launch vehicle systems engineer. He retired from the U.S. Air Force Reserve with the rank of colonel in 2005. Prior to 1990, Pestana was on active duty with the U.S. Air Force as the director of mi
Guidewire retention following central venous catheterisation: a human factors and safe design investigation.

PubMed

Horberry, Tim; Teng, Yi-Chun; Ward, James; Patil, Vishal; Clarkson, P John

2014-01-01

Central Venous Catheterisation (CVC) has occasionally been associated with cases of retained guidewires in patients after surgery. In theory, this is a completely avoidable complication; however, as with any human procedure, operator error leading to guidewires being occasionally retained cannot be fully eliminated. The work described here investigated the issue in an attempt to better understand it both from an operator and a systems perspective, and to ultimately recommend appropriate safe design solutions that reduce guidewire retention errors. Nine distinct methods were used: observations of the procedure, a literature review, interviewing CVC end-users, task analysis construction, CVC procedural audits, two human reliability assessments, usability heuristics and a comprehensive solution survey with CVC end-users. The three solutions that operators rated most highly, in terms of both practicality and effectiveness, were: making trainees better aware of the potential guidewire complications and strongly emphasising guidewire removal in CVC training, actively checking that the guidewire is present in the waste tray for disposal, and standardising purchase of central line sets so that differences that may affect chances of guidewire loss is minimised. Further work to eliminate/engineer out the possibility of guidewires being retained is proposed.
75 FR 64303 - Vermont Marble Power, Division of Omya Inc.; Central Vermont Public Service Corporation; Notice...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-19

...-029; 2445-023; 2558-029] Vermont Marble Power, Division of Omya Inc.; Central Vermont Public Service... Soliciting Comments and Motions To Intervene October 12, 2010. On August 31, 2010, Vermont Marble Power... relicensing. Applicant Contacts: For transferor: Todd Allard, Operations Engineer Omya, Inc., Vermont Marble...
Accumulation of radium in sediments from continued disposal of produced water and hydraulic fracturing flowback water

NASA Astrophysics Data System (ADS)

Warner, N. R.; Menio, E. C.; Landis, J. D.; Vengosh, A.; Lauer, N.; Harkness, J.; Kondash, A.

2014-12-01

Recent public interest in high volume slickwater hydraulic fracturing (HVHF) has drawn increased interest in wastewater management practices by the public, researchers, industry, and regulators. The management of wastes, including both fluids and solids, poses many engineering challenges, including elevated total dissolved solids and elevated activities of naturally occurring radioactive materials (NORM). One management option for wastewater in particular, which is used in western Pennsylvania, USA, is treatment at centralized waste treatment facilities [1]. Previous studies conducted from 2010-2012 indicated that one centralized facility, the Josephine Brine Treatment facility, removed the majority of radium from produced water and hydraulic fracturing flowback fluid (HFFF) during treatment, but low activities of radium remained in treated effluent and were discharged to surface water [2]. Despite the treatment process and radium reduction, high activities (200 times higher than upstream/background) accumulated in stream sediments at the point of effluent discharge. Here we present new results from sampling conducted at two additional centralized waste treatment facilities (Franklin Brine Treatment and Hart Brine Treatment facilities) and Josephine Brine Treatment facility conducted in June 2014. Preliminary results indicate radium is released to surface water at very low (<50 pCi/L) to non-detectable activities, however; radium continues to accumulate in sediments surrounding the area of effluent release. Combined, the data indicate that 1) radium continues to be released to surface water streams in western Pennsylvania despite oil and gas operators voluntary ban on treatment and disposal of HFFF in centralized waste treatment facilities, 2) radium accumulation in sediments occurred at multiple brine treatment facilities and is not isolated to a single accidental release of contaminants or a single facility. [1] Wilson, J. M. and J. M. VanBriesen (2012). "Oil and Gas Produced Water Management and Surface Drinking Water Sources in Pennsylvania." Environmental Practice 14(04): 288-300. [2] Warner, N. R., C. A. Christie, R. B. Jackson and A. Vengosh (2013). "Impacts of Shale Gas Wastewater Disposal on Water Quality in Western Pennsylvania." ES&T 47(20): 11849-11857.
Hybrid multiphoton volumetric functional imaging of large-scale bioengineered neuronal networks

NASA Astrophysics Data System (ADS)

Dana, Hod; Marom, Anat; Paluch, Shir; Dvorkin, Roman; Brosh, Inbar; Shoham, Shy

2014-06-01

Planar neural networks and interfaces serve as versatile in vitro models of central nervous system physiology, but adaptations of related methods to three dimensions (3D) have met with limited success. Here, we demonstrate for the first time volumetric functional imaging in a bioengineered neural tissue growing in a transparent hydrogel with cortical cellular and synaptic densities, by introducing complementary new developments in nonlinear microscopy and neural tissue engineering. Our system uses a novel hybrid multiphoton microscope design combining a 3D scanning-line temporal-focusing subsystem and a conventional laser-scanning multiphoton microscope to provide functional and structural volumetric imaging capabilities: dense microscopic 3D sampling at tens of volumes per second of structures with mm-scale dimensions containing a network of over 1,000 developing cells with complex spontaneous activity patterns. These developments open new opportunities for large-scale neuronal interfacing and for applications of 3D engineered networks ranging from basic neuroscience to the screening of neuroactive substances.
A usability study of CPOE's medication administration functions: impact on physician-nurse cooperation.

PubMed

Beuscart-Zéphir, Marie Catherine; Pelayo, Sylvia; Degoulet, Patrice; Anceaux, Françoise; Guerlinger, Sandra; Meaux, Jean-Jacques

2004-01-01

Implementation of CPOE systems in Healthcare Institutions has proven efficient in reducing medication errors but it also induces hidden side-effects on Doctor-Nurse cooperation. We propose a usability engineering approach to this problem. An extensive activity analysis of the medication ordering and administration process was performed in several departments of 3 different hospitals. Two of these hospitals are still using paper-based orders, while the 3rd one is in the roll-out phase of medication functions of its CPOE system. We performed a usability assessment of this CPOE system. The usability assessment uncovered usability problems for the entry of medication administration time scheduling by the physician and revealed that the information can be ambiguous for the nurse. The comparison of cooperation models in both situation shows that users tend to adopt a distributed decision making paradigm in the paper-based situation, while the CPOE system supports a centralized decision making process. This analysis can support recommendation for the re-engineering of the Human-Computer Interface.
Support for International Space University?s (ISU) 2003 Summer Session Program and the Theme Day on ?Living and Working in Space?

NASA Technical Reports Server (NTRS)

Finarelli, Margaret G.

2004-01-01

The 2003 Summer Session Program of the International Space University (ISU) was conducted at the ISU Central Campus in Strasbourg, France, July 5-September 6, 2003. Attending the Summer Session were 114 students from 27 countries including the US. The International Space University (ISU) offers its students a unique and comprehensive educational package covering all disciplines related to space programs and enterprises - space science, space engineering, systems engineering, space policy and law, business and management, and space and society. By providing international graduate students and young space professionals both an intensive interdisciplinary curriculum and also the opportunity to solve complex problems together in an intercultural environment, ISU is preparing the future leaders of the emerging global space community. Since its founding in 1988, ISU has graduated more than 2200 students from 87 countries. Together with hundreds of ISU faculty and lecturers from around the world, ISU alumni comprise an extremely effective network of space professionals and leaders that actively facilitates individual career growth, professional activities and international space cooperation. ISU's interdisciplinary Student Theme Days and Student Workshops are intended to have great educational value for the participants. Along with the interdisciplinary Core Lectures, they apprise the students of state-of-the-art activities, programs and policies in spacefaring nations. They also provide ISU students the opportunity to meet world experts in space-related subjects.
Novel enzymatically cross-linked hyaluronan hydrogels support the formation of 3D neuronal networks.

PubMed

Broguiere, Nicolas; Isenmann, Luca; Zenobi-Wong, Marcy

2016-08-01

Hyaluronan (HA) is an essential component of the central nervous system's extracellular matrix and its high molecular weight (MW) form has anti-inflammatory and anti-fibrotic properties relevant for regenerative medicine. Here, we introduce a new hydrogel based on high MW HA which is cross-linked using the transglutaminase (TG) activity of the activated blood coagulation factor XIII (FXIIIa). These HA-TG gels have significant advantages for neural tissue engineering compared to previous HA gels. Due to their chemical inertness in the absence of FXIIIa, the material can be stored long-term, is stable in solution, and shows no cytotoxicity. The gelation is completely cell-friendly due to the specificity of the enzyme and the gelation rate can be tuned from seconds to hours at physiological pH and independently of stiffness. The gels are injectable, and attach covalently to fibrinogen and fibrin, two common bioactive components in in vitro tissue engineering, as well as proteins present in vivo, allowing the gels to covalently bind to brain or spinal cord defects. These optimal chemical and bioactive properties of HA-TG gels enabled the formation of 3D neuronal cultures of unprecedented performance, showing fast neurite outgrowth, axonal and dendritic speciation, strong synaptic connectivity in 3D networks, and rapidly-occurring and long-lasting coordinated electrical activity. Copyright © 2016 Elsevier Ltd. All rights reserved.
Product diffusion through on-demand information-seeking behaviour.

PubMed

Riedl, Christoph; Bjelland, Johannes; Canright, Geoffrey; Iqbal, Asif; Engø-Monsen, Kenth; Qureshi, Taimur; Sundsøy, Pål Roe; Lazer, David

2018-02-01

Most models of product adoption predict S-shaped adoption curves. Here we report results from two country-scale experiments in which we find linear adoption curves. We show evidence that the observed linear pattern is the result of active information-seeking behaviour: individuals actively pulling information from several central sources facilitated by modern Internet searches. Thus, a constant baseline rate of interest sustains product diffusion, resulting in a linear diffusion process instead of the S-shaped curve of adoption predicted by many diffusion models. The main experiment seeded 70 000 (48 000 in Experiment 2) unique voucher codes for the same product with randomly sampled nodes in a social network of approximately 43 million individuals with about 567 million ties. We find that the experiment reached over 800 000 individuals with 80% of adopters adopting the same product-a winner-take-all dynamic consistent with search engine driven rankings that would not have emerged had the products spread only through a network of social contacts. We provide evidence for (and characterization of) this diffusion process driven by active information-seeking behaviour through analyses investigating (a) patterns of geographical spreading; (b) the branching process; and (c) diffusion heterogeneity. Using data on adopters' geolocation we show that social spreading is highly localized, while on-demand diffusion is geographically independent. We also show that cascades started by individuals who actively pull information from central sources are more effective at spreading the product among their peers. © 2018 The Authors.
Product diffusion through on-demand information-seeking behaviour

PubMed Central

Bjelland, Johannes; Canright, Geoffrey; Iqbal, Asif; Qureshi, Taimur; Sundsøy, Pål Roe

2018-01-01

Most models of product adoption predict S-shaped adoption curves. Here we report results from two country-scale experiments in which we find linear adoption curves. We show evidence that the observed linear pattern is the result of active information-seeking behaviour: individuals actively pulling information from several central sources facilitated by modern Internet searches. Thus, a constant baseline rate of interest sustains product diffusion, resulting in a linear diffusion process instead of the S-shaped curve of adoption predicted by many diffusion models. The main experiment seeded 70 000 (48 000 in Experiment 2) unique voucher codes for the same product with randomly sampled nodes in a social network of approximately 43 million individuals with about 567 million ties. We find that the experiment reached over 800 000 individuals with 80% of adopters adopting the same product—a winner-take-all dynamic consistent with search engine driven rankings that would not have emerged had the products spread only through a network of social contacts. We provide evidence for (and characterization of) this diffusion process driven by active information-seeking behaviour through analyses investigating (a) patterns of geographical spreading; (b) the branching process; and (c) diffusion heterogeneity. Using data on adopters' geolocation we show that social spreading is highly localized, while on-demand diffusion is geographically independent. We also show that cascades started by individuals who actively pull information from central sources are more effective at spreading the product among their peers. PMID:29467257
Violence in the hearts of galaxies: aberration or adolescence?

PubMed

Mundell, Carole G

2002-12-15

Violent activity in the nuclei of galaxies has long been considered a curiosity in its own right; manifestations of this phenomenon include distant quasars in the early Universe and comparatively nearby Seyfert galaxies, both thought to be powered by the release of gravitational potential energy as material from the host galaxy accretes onto a central supermassive black hole (SMBH). Traditionally, the broader study of the formation, structure and evolution of galaxies has largely excluded active galactic nuclei. Recently, however, this situation has changed dramatically, both observationally and theoretically, with the realization that the growth and influence of the SMBH, the origin and development of galaxies and nuclear activity at different epochs in the Universe may be intimately related. The most spectacular fireworks seen in distant quasars may be relatively easy to explain, since the era of greatest quasar activity seems to coincide with turbulent dynamics at the epoch of galaxy formation in the young, gas-rich Universe. Ubiquitous black holes are believed to be a legacy of this violent birth. Alternatively, black holes may be the seeds that drive galaxy formation in the first place. Closer to home, and hence more recently in the history of the Universe, a fraction of comparatively ordinary galaxies, similar to our own, has reignited their central engines, albeit at a lower level of activity. Since these galaxies are more established than their younger and more distant counterparts, the activity here is all the more puzzling. Whatever the mechanisms involved, they are likely to play an important role in galaxy evolution. I review the intriguing evidence for causal links between SMBHs, nuclear activity and the formation and evolution of galaxies, and describe opportunities for testing these relationships using the next generation of earthbound and space-borne astronomical facilities.
Project-based learning in a high school engineering program: A case study

NASA Astrophysics Data System (ADS)

France, Todd

Generating greater student interest in science, technology, engineering, and mathematics (STEM) has been a major topic of discussion among educators, policymakers, and researchers in recent years, as increasing the number of graduates in these fields is widely considered a necessary step for sustaining the progress of today's society. Fostering this interest must occur before students reach college, and substantial efforts have been made to engage students at K-12 levels in STEM-focused learning. Attempts to involve students in engineering, a vital and growing profession, yet one in which students often have little experience, have frequently emphasized the design and construction of physical products, a practice supported by project-based learning. This thesis examines the environment of an engineering high school course that employed the project-based model. The course is part of a dedicated curricular program which aims to provide students with positive experiences in engineering-related activities while also preparing them for the rigors of college. A case study was conducted to provide insight into the benefits and drawbacks of the learning model. The study's outcomes are intended to provide guidance to educators participating in the design and/or facilitation of project-based activities, particularly those involved with engineering education. The research was performed using a qualitative approach. Long-term engagement with course participants was deemed critical to gaining a comprehensive understanding of the interactions and events that transpired on a daily basis. Nine educators involved with the program were interviewed, as were nineteen of the course's thirty-nine students. A wealth of other relevant data -- including surveys, field notes, and evaluations of student work -- was compiled for analysis as well. The study findings suggest that experiences in problem solving and teamwork were the central benefits of the course. Limitations existed due to a high focus on hands-on work, which infringed upon the significance of math and science content as well as the utilization of disciplined inquiry. In addition, group projects failed to hold individuals accountable, leading to assessment challenges. Program-wide, a number of issues hindered the teachers' abilities to institute changes, most notably a commitment to serve students of all abilities.
Assessing the Workforce Outcomes of Maryland Science, Technology, Engineering, and Math (STEM) Postsecondary Graduates

ERIC Educational Resources Information Center

Zheng, Xiaying; Stapleton, Laura M.; Henneberger, Angela K.; Woolley, Michael E.

2016-01-01

The science, technology, engineering, and math (STEM) workforce, and therefore STEM education, has become increasingly central to the U.S. economic growth and competitiveness over the past five decades. Nationally, the number of STEM workforce positions and the number of STEM postsecondary graduates have increased over time, but there is…
The National Science Foundation Strategic Framework for Investments in Graduate Education. FY 2016-FY 2020. Revised

ERIC Educational Resources Information Center

National Science Foundation, 2016

2016-01-01

Graduate education plays a central role in advancing the Nation's science and engineering research enterprise. It is also increasingly the means by which the Nation develops a diverse and highly technical Science Technology Engineering and Mathematics (STEM) professional workforce. The view that graduate education in STEM disciplines is an…
Language Aspects of Engineering Students' View of Entropy

ERIC Educational Resources Information Center

Haglund, Jesper; Andersson, Staffan; Elmgren, Maja

2016-01-01

Entropy is a central concept in thermodynamics, but has been found to be challenging to students due to its abstract nature and the fact that it is not part of students' everyday language. Interviews with three pairs of engineering students (N = 6) were conducted and video recorded regarding their interpretation and use of the entropy concept, one…
Geological Character and Mineral Resources of South Central Lake Erie.

DTIC Science & Technology

1982-10-01

Presque Isle Peninsula, Erie , Pennsylvania , being conducted by the U.S. Army Engineer District...the Pennsylvania shoreline. Because of its position and morphology, Presque Isle acts as a natural offshore breakwater for Erie Harbor, blocking the...Research Center, Fort Belvoir, Va. (in preparation, 1982). U.S. ARMY ENGINEER DISTRICT, BUFFALO, " Presque Isle Peninsula, Erie , Pennsylvania ,"
Designing "Design Squad": Developing and Assessing a Children's Television Program about Engineering

ERIC Educational Resources Information Center

Frey, Daniel David; Powers, Benjamin

2012-01-01

This paper describes a multi-media outreach campaign intended to increase children's knowledge of engineering and to improve the public image of the profession. The central element is a reality-based show entitled "Design Squad," whose first season was broadcast on public television stations beginning in the spring of 2007. The show was…
Observing Engineering Student Teams from the Organization Behavior Perspective Using Linguistic Analysis of Student Reflections and Focus Group Interviews

ERIC Educational Resources Information Center

Kearney, Kerri S.; Damron, Rebecca; Sohoni, Sohum

2015-01-01

This paper investigates group/team development in computer engineering courses at a University in the Central USA from the perspective of organization behavior theory, specifically Tuckman's model of the stages of group development. The investigation, conducted through linguistic analysis of student reflection essays, and through focus group…

Potent Immune Modulation by MEDI6383, an Engineered Human OX40 Ligand IgG4P Fc Fusion Protein.

PubMed

Oberst, Michael D; Augé, Catherine; Morris, Chad; Kentner, Stacy; Mulgrew, Kathy; McGlinchey, Kelly; Hair, James; Hanabuchi, Shino; Du, Qun; Damschroder, Melissa; Feng, Hui; Eck, Steven; Buss, Nicholas; de Haan, Lolke; Pierce, Andrew J; Park, Haesun; Sylwester, Andrew; Axthelm, Michael K; Picker, Louis; Morris, Nicholas P; Weinberg, Andrew; Hammond, Scott A

2018-05-01

Ligation of OX40 (CD134, TNFRSF4) on activated T cells by its natural ligand (OX40L, CD252, TNFSF4) enhances cellular survival, proliferation, and effector functions such as cytokine release and cellular cytotoxicity. We engineered a recombinant human OX40L IgG4P Fc fusion protein termed MEDI6383 that assembles into a hexameric structure and exerts potent agonist activity following engagement of OX40. MEDI6383 displayed solution-phase agonist activity that was enhanced when the fusion protein was clustered by Fc gamma receptors (FcγRs) on the surface of adjacent cells. The resulting costimulation of OX40 on T cells induced NFκB promoter activity in OX40-expressing T cells and induced Th1-type cytokine production, proliferation, and resistance to regulatory T cell (Treg)-mediated suppression. MEDI6383 enhanced the cytolytic activity of tumor-reactive T cells and reduced tumor growth in the context of an alloreactive human T cell:tumor cell admix model in immunocompromised mice. Consistent with the role of OX40 costimulation in the expansion of memory T cells, MEDI6383 administered to healthy nonhuman primates elicited peripheral blood CD4 and CD8 central and effector memory T-cell proliferation as well as B-cell proliferation. Together, these results suggest that OX40 agonism has the potential to enhance antitumor immunity in human malignancies. Mol Cancer Ther; 17(5); 1024-38. ©2018 AACR . ©2018 American Association for Cancer Research.
Macrophage-mediated trogocytosis leads to death of antibody-opsonized tumor cells

PubMed Central

Velmurugan, Ramraj; Challa, Dilip K.; Ram, Sripad; Ober, Raimund J.; Ward, E. Sally

2016-01-01

Understanding the complex behavior of effector cells such as monocytes or macrophages in regulating cancerous growth is of central importance for cancer immunotherapy. Earlier studies using CD20-specific antibodies have demonstrated that the Fcγ receptor (FcγR)-mediated transfer of the targeted receptors from tumor cells to these effector cells through trogocytosis can enable escape from antibody therapy, leading to the viewpoint that this process is pro-tumorigenic. In the current study we demonstrate that persistent trogocytic attack results in the killing of HER2-overexpressing breast cancer cells. Further, antibody engineering to increase FcγR interactions enhances this tumoricidal activity. These studies extend the complex repertoire of activities of macrophages to trogocytic-mediated cell death of HER2-overexpressing target cells and have implications for the development of effective antibody-based therapies. PMID:27226489
F101 Central Integrated Test Subsystem Evaluation.

DTIC Science & Technology

1980-02-01

These sensors are for fan rpm, core rpm, nozzle position, turbine blade temperature, engine exhaust gas tem- perature, lube oil pressure, lube oil...condition or a turbine blade (T4B) overtemperature condition, the CITS was to record the out-of-limits parameter every quarter-second that the engine was in...cycles on the turbine blades . The PLA cycle has become the most important LCF measurement to the YF101 and F1O engines in the B-1 Flight Test Program
Introduction: seismology and earthquake engineering in Mexico and Central and South America.

USGS Publications Warehouse

Espinosa, A.F.

1982-01-01

The results from seismological studies that are used by the engineering community are just one of the benefits obtained from research aimed at mitigating the earthquake hazard. In this issue of Earthquake Information Bulletin current programs in seismology and earthquake engineering, seismic networks, future plans and some of the cooperative programs with different internation organizations are described by Latin-American seismologists. The article describes the development of seismology in Latin America and the seismological interest of the OAS. -P.N.Chroston
Enhanced pyruvate production in Candida glabrata by carrier engineering.

PubMed

Luo, Zhengshan; Liu, Song; Du, Guocheng; Xu, Sha; Zhou, Jingwen; Chen, Jian

2018-02-01

Pyruvate is an important organic acid that plays a key role in the central metabolic pathway. Manipulating transporters is an efficient strategy to enhance production of target organic acids and a means to understand the effects of altered intracellular pyruvate content on global metabolic networks. Efforts have been made to manipulate mitochondrial pyruvate carrier (MPC) to transport pyruvate into different subcellular compartments in Candida glabrata to demonstrate the effects of the subcellular distribution of pyruvate on central carbon metabolism. By increasing the mitochondrial pyruvate content through enhancing the rate of pyruvate transport into mitochondria, a high central carbon metabolism rate, specific growth rate and specific pyruvate production rate were obtained. Comparing the intracellular pyruvate content of engineered and control strains showed that higher intracellular pyruvate levels were not conducive to improving pyruvate productivity or central carbon metabolism. Plasma membrane expression of MPCs significantly increased the expression levels of key rate-limiting glycolytic enzymes. Moreover, pyruvate production of CGΔura3-Sp-MPC1, CGΔura3-Sp-MPC2, and CGΔura3-Sp-MPC1-Sp-MPC2 increased 134.4%, 120.3%, and 30.0%, respectively. In conclusion, lower intracellular pyruvate content enhanced central carbon metabolism and provided useful clues for improving the production of other organic acids in microorganisms. © 2017 Wiley Periodicals, Inc.
New Compressor Added to Glenn's 450- psig Combustion Air System

NASA Technical Reports Server (NTRS)

Swan, Jeffrey A.

2000-01-01

In September 1999, the Central Process Systems Engineering Branch and the Maintenance and the Central Process Systems Operations Branch, released for service a new high pressure compressor to supplement the 450-psig Combustion Air System at the NASA Glenn Research Center at Lewis Field. The new compressor, designated C-18, is located in Glenn s Central Air Equipment Building and is remotely operated from the Central Control Building. C-18 can provide 40 pounds per second (pps) of airflow at pressure to our research customers. This capability augments our existing system capacity (compressors C 4 at 38 pps and C-5 at 32 pps), which is generated from Glenn's Engine Research Building. The C-18 compressor was originally part of Glenn's 21-Inch Hypersonic Tunnel, which was transferred from the Jet Propulsion Laboratory to Glenn in the mid-1980's. With the investment of construction of facilities funding, the compressor was modified, new mechanical and electrical support equipment were purchased, and the unit was installed in the basement of the Central Air Equipment Building. After several weeks of checkout and troubleshooting, the new compressor was ready for long-term, reliable operations. With a total of 110 pps in airflow now available, Glenn is well positioned to support the high-pressure air test requirements of our research customers.
Drone Defense System Architecture for U.S. Navy Strategic Facilities

DTIC Science & Technology

2017-09-01

evaluation and weapons assignment (TEWA) to properly address threats. This report follows a systems engineering process to develop a software architecture...C-UAS requires a central system to connect these new and existing systems. The central system uses data fusion and threat evaluation and weapons...30 Table 6. Decision Type Descriptions .......................................................................40 Table 7
Centralized waste treatment of industrial wastewater

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

Saltzberg, E.R.; Cushnie, G.C. Jr.

1985-01-01

Centralized waste treatment (CWT) for industrial wastewater is described in this book. With the CWT approach, industrial firms send their wastes to a common processing plant. The book addresses the engineering and business-related problems that are encountered by private CWT firms, local governments, and industry in creating sufficient CWT capacity to meet the growing demand for CWT services.
The logics of metabolic regulation in bacteria challenges biosensor-based metabolic engineering.

PubMed

Jules, Matthieu

2017-12-11

Synthetic Biology (SB) aims at the rational design and engineering of novel biological functions and systems. By facilitating the engineering of living organisms, SB promises to facilitate the development of many new applications for health, biomanufacturing, and the environment. Over the last decade, SB promoted the construction of libraries of components enabling the fine-tuning of genetic circuits expression and the development of novel genome engineering methodologies for many organisms of interest. SB thus opened new perspectives in the field of metabolic engineering, which was until then mainly limited to (over)producing naturally synthesized metabolic compounds. To engineer efficient cell factories, it is key to precisely reroute cellular resources from the central carbon metabolism (CCM) to the synthetic circuitry. This task is however difficult as there is still significant lack of knowledge regarding both the function of several metabolic components and the regulation of the CCM fluxes for many industrially important bacteria. Pyruvate is a pivotal metabolite at the heart of the CCM and a key precursor for the synthesis of several commodity compounds and fine chemicals. Numerous bacterial species can also use it as a carbon source when present in the environment but bacterial, pyruvate-specific uptake systems were to be discovered. This is an issue for metabolic engineering as one can imagine to make use of pyruvate transport systems to replenish synthetic metabolic pathways towards the synthesis of chemicals of interest. Here we describe a recent study (MBio 8(5): e00976-17), which identified and characterized a pyruvate transport system in the Gram-positive (G +ve ) bacterium Bacillus subtilis , a well-established biotechnological workhorse for the production of enzymes, fine chemicals and antibiotics. This study also revealed that the activity of the two-component system (TCS) responsible for its induction is retro-inhibited by the level of pyruvate influx. Following up on the open question which is whether this retro-inhibition is a generic mechanism for TCSs, we will discuss the implications in metabolic engineering.
The philosophical and pedagogical underpinnings of Active Learning in Engineering Education

NASA Astrophysics Data System (ADS)

Christie, Michael; de Graaff, Erik

2017-01-01

In this paper the authors draw on three sequential keynote addresses that they gave at Active Learning in Engineering Education (ALE) workshops in Copenhagen (2012), Caxias do Sol (2014) and San Sebastian (2015). Active Learning in Engineering Education is an informal international network of engineering educators dedicated to improving engineering education through active learning (http://www.ale-net.org/). The paper reiterates themes from those keynotes, namely, the philosophical and pedagogical underpinnings of Active Learning in Engineering Education, the scholarly questions that inspire engineering educators to go on improving their practice and exemplary models designed to activate the learning of engineering students. This paper aims to uncover the bedrock of established educational philosophies and theories that define and support active learning. The paper does not claim to present any new or innovative educational theory. There is already a surfeit of them. Rather, the aim is to assist Engineering Educators who wish to research how they can best activate the learning of their students by providing a readable, reasonable and solid underpinning for best practice in this field.
A Method for Search Engine Selection using Thesaurus for Selective Meta-Search Engine

NASA Astrophysics Data System (ADS)

Goto, Shoji; Ozono, Tadachika; Shintani, Toramatsu

In this paper, we propose a new method for selecting search engines on WWW for selective meta-search engine. In selective meta-search engine, a method is needed that would enable selecting appropriate search engines for users' queries. Most existing methods use statistical data such as document frequency. These methods may select inappropriate search engines if a query contains polysemous words. In this paper, we describe an search engine selection method based on thesaurus. In our method, a thesaurus is constructed from documents in a search engine and is used as a source description of the search engine. The form of a particular thesaurus depends on the documents used for its construction. Our method enables search engine selection by considering relationship between terms and overcomes the problems caused by polysemous words. Further, our method does not have a centralized broker maintaining data, such as document frequency for all search engines. As a result, it is easy to add a new search engine, and meta-search engines become more scalable with our method compared to other existing methods.
Partitioning of centralized integrated flight/propulsion control design for decentralized implementation

NASA Technical Reports Server (NTRS)

Garg, Sanjay

1993-01-01

The notion of partitioning a centralized controller into a decentralized, hierarchical structure suitable for integrated flight/propulsion control (IFPC) implementation is discussed. A systematic procedure is developed for determining partitioned airframe and engine subsystem controllers (subcontrollers), with the desired interconnection structure, that approximate the closed-loop performance and robustness characteristics of a given centralized controller. The procedure is demonstrated by application to IFPC design for a short take-off and vertical landing (STOVL) aircraft in the landing-approach-to-hover-transition flight phase.
Preparing engineers for the challenges of community engagement

NASA Astrophysics Data System (ADS)

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

2017-11-01

Despite calls to address global challenges through community engagement, engineers are not formally prepared to engage with communities. Little research has been done on means to address this 'engagement gap' in engineering education. We examine the efficacy of an intensive, two-day Community Engagement Workshop for engineers, designed to help engineers better look beyond technology, listen to and learn from people, and empower communities. We assessed the efficacy of the workshop in a non-experimental pre-post design using a questionnaire and a concept map. Questionnaire results indicate participants came away better able to ask questions more broadly inclusive of non-technological dimensions of engineering projects. Concept map results indicate participants have a greater understanding of ways social factors shape complex material systems after completing the programme. Based on the workshop's strengths and weaknesses, we discuss the potential of expanding and supplementing the programme to help engineers account for social aspects central to engineered systems.
Mathematics and its value for engineering students: what are the implications for teaching?

NASA Astrophysics Data System (ADS)

Harris, Diane; Black, Laura; Hernandez-Martinez, Paul; Pepin, Birgit; Williams, Julian; with the TransMaths Team

2015-04-01

Mathematics has long been known to be problematic for university engineering students and their teachers, for example, Scanlan.[1] This paper presents recent data gathered from interviews with engineering students who experienced problems with mathematics and their lecturers during their transition through the first year in different programme contexts. Our interviews with the students reveal how they understand the relation between engineering and mathematics and we draw on the concept of 'use- and exchange-value' to explore this relationship more fully. This paper challenges both the pedagogical practice of teaching non-contextualized mathematics and the lack of transparency regarding the significance of mathematics to engineering. We conclude that the value of mathematics in engineering remains a central problem, and argue that mathematics should be a fundamental concern in the design and practice of first-year engineering.
Active Learning in Engineering Education: A (Re)Introduction

ERIC Educational Resources Information Center

Lima, Rui M.; Andersson, Pernille Hammar; Saalman, Elisabeth

2017-01-01

The informal network "Active Learning in Engineering Education" (ALE) has been promoting Active Learning since 2001. ALE creates opportunity for practitioners and researchers of engineering education to collaboratively learn how to foster learning of engineering students. The activities in ALE are centred on the vision that learners…
Rapid Optimization of Engineered Metabolic Pathways with Serine Integrase Recombinational Assembly (SIRA).

PubMed

Merrick, C A; Wardrope, C; Paget, J E; Colloms, S D; Rosser, S J

2016-01-01

Metabolic pathway engineering in microbial hosts for heterologous biosynthesis of commodity compounds and fine chemicals offers a cheaper, greener, and more reliable method of production than does chemical synthesis. However, engineering metabolic pathways within a microbe is a complicated process: levels of gene expression, protein stability, enzyme activity, and metabolic flux must be balanced for high productivity without compromising host cell viability. A major rate-limiting step in engineering microbes for optimum biosynthesis of a target compound is DNA assembly, as current methods can be cumbersome and costly. Serine integrase recombinational assembly (SIRA) is a rapid DNA assembly method that utilizes serine integrases, and is particularly applicable to rapid optimization of engineered metabolic pathways. Using six pairs of orthogonal attP and attB sites with different central dinucleotide sequences that follow SIRA design principles, we have demonstrated that ΦC31 integrase can be used to (1) insert a single piece of DNA into a substrate plasmid; (2) assemble three, four, and five DNA parts encoding the enzymes for functional metabolic pathways in a one-pot reaction; (3) generate combinatorial libraries of metabolic pathway constructs with varied ribosome binding site strengths or gene orders in a one-pot reaction; and (4) replace and add DNA parts within a construct through targeted postassembly modification. We explain the mechanism of SIRA and the principles behind designing a SIRA reaction. We also provide protocols for making SIRA reaction components and practical methods for applying SIRA to rapid optimization of metabolic pathways. © 2016 Elsevier Inc. All rights reserved.
Disks and cones: interferometry of the dusty and molecular material of AGN on parsec sales

NASA Astrophysics Data System (ADS)

Tristam, Konrad R. W.

2016-08-01

The central engine of Active Galactic Nuclei (AGN) is surrounded by dense molecular and dusty material on parsec scales. Typically referred to as the ""dusty torus"", this material is a key ingredient of AGN because it (1) provides the angle dependent obscuration of the central engine and (2) most likely plays an important role for the accretion of the material onto the supermassive black hole. Observations using interferometry in the infrared have, in the last ten years, resolved and characterised the thermal emission from the dust heated by the AGN beyond simple fits of the spectral energy distribution, leading to a great leap forward in our view of the dusty material surrounding AGN. In general the torus is parsec-sized, with a large scatter in extension between individual objects. Our studies have led to the surprising discovery that the dust emission is clearly separated into two distinct components: an inner disk-like emission region which is surrounded by a polar elongated emitter. I will demonstrate these discoveries using the results obtained for the Circinus galaxy, and discuss how the results for this galaxy compare to other well studied sources. While putting strong constraints on torus models, our findings are in good qualitative agreement with recent hydrodynamic simulations of AGN tori. The next big step forward can be expected from sub-mm interferometry and I will give a short glimpse at the results from our recent ALMA observations of the outer torus in the Circinus galaxy.
An economic analysis of adherence engineering to improve use of best practices during central line maintenance procedures.

PubMed

Nelson, Richard E; Angelovic, Aaron W; Nelson, Scott D; Gleed, Jeremy R; Drews, Frank A

2015-05-01

Adherence engineering applies human factors principles to examine non-adherence within a specific task and to guide the development of materials or equipment to increase protocol adherence and reduce human error. Central line maintenance (CLM) for intensive care unit (ICU) patients is a task through which error or non-adherence to protocols can cause central line-associated bloodstream infections (CLABSIs). We conducted an economic analysis of an adherence engineering CLM kit designed to improve the CLM task and reduce the risk of CLABSI. We constructed a Markov model to compare the cost-effectiveness of the CLM kit, which contains each of the 27 items necessary for performing the CLM procedure, compared with the standard care procedure for CLM, in which each item for dressing maintenance is gathered separately. We estimated the model using the cost of CLABSI overall ($45,685) as well as the excess LOS (6.9 excess ICU days, 3.5 excess general ward days). Assuming the CLM kit reduces the risk of CLABSI by 100% and 50%, this strategy was less costly (cost savings between $306 and $860) and more effective (between 0.05 and 0.13 more quality-adjusted life-years) compared with not using the pre-packaged kit. We identified threshold values for the effectiveness of the kit in reducing CLABSI for which the kit strategy was no longer less costly. An adherence engineering-based intervention to streamline the CLM process can improve patient outcomes and lower costs. Patient safety can be improved by adopting new approaches that are based on human factors principles.
Implementation of a Goal-Based Systems Engineering Process Using the Systems Modeling Language (SysML)

NASA Technical Reports Server (NTRS)

Patterson, Jonathan D.; Breckenridge, Jonathan T.; Johnson, Stephen B.

2013-01-01

Building upon the purpose, theoretical approach, and use of a Goal-Function Tree (GFT) being presented by Dr. Stephen B. Johnson, described in a related Infotech 2013 ISHM abstract titled "Goal-Function Tree Modeling for Systems Engineering and Fault Management", this paper will describe the core framework used to implement the GFTbased systems engineering process using the Systems Modeling Language (SysML). These two papers are ideally accepted and presented together in the same Infotech session. Statement of problem: SysML, as a tool, is currently not capable of implementing the theoretical approach described within the "Goal-Function Tree Modeling for Systems Engineering and Fault Management" paper cited above. More generally, SysML's current capabilities to model functional decompositions in the rigorous manner required in the GFT approach are limited. The GFT is a new Model-Based Systems Engineering (MBSE) approach to the development of goals and requirements, functions, and its linkage to design. As a growing standard for systems engineering, it is important to develop methods to implement GFT in SysML. Proposed Method of Solution: Many of the central concepts of the SysML language are needed to implement a GFT for large complex systems. In the implementation of those central concepts, the following will be described in detail: changes to the nominal SysML process, model view definitions and examples, diagram definitions and examples, and detailed SysML construct and stereotype definitions.
Orbiting Water Molecules Dance to Tune Of Galaxy's "Central Engine," Astronomers Say

NASA Astrophysics Data System (ADS)

2000-01-01

A disk of water molecules orbiting a supermassive black hole at the core of a galaxy 60 million light-years away is "reverberating" in response to variations in the energy output from the galaxy's powerful "central engine" close to the black hole, astronomers say. The team of astronomers used the National Science Foundation's (NSF) Very Large Array (VLA) radio telescope in New Mexico and the 100-meter-diameter radio telescope of the Max Planck Institute for Radio Astronomy at Effelsberg, Germany, to observe the galaxy NGC 1068 in the constellation Cetus. They announced their findings today at the American Astronomical Society's meeting in Atlanta. The water molecules, in a disk some 5 light-years in diameter, are acting as a set of giant cosmic radio-wave amplifiers, called masers. Using energy radiated by the galaxy's "central engine," the molecules strengthen, or brighten, radio emission at a particular frequency as seen from Earth. "We have seen variations in the radio 'brightness' of these cosmic amplifiers that we believe were caused by variations in the energy output of the central engine," said Jack Gallimore, an astronomer at the National Radio Astronomy Observatory (NRAO) in Charlottesville, VA. "This could provide us with a valuable new tool for learning about the central engine itself," he added. Gallimore worked with Stefi Baum of the Space Telescope Science Institute in Baltimore, MD; Christian Henkel of the Max Planck Institute for Radio Astronomy in Bonn, Germany; Ian Glass of the South African Astronomical Observatory; Mark Claussen of the NRAO in Socorro, NM; and Almudena Prieto of the European Southern Observatory in Munich, Germany. "Our observations show that NGC 1068 is the second-known case of a giant disk of water molecules orbiting a supermassive black hole at a galaxy's core," Gallimore said. The first case was the galaxy NGC 4258 (Messier 106), whose disk of radio-amplifying water molecules was measured by the NSF's Very Long Baseline Array (VLBA) radio telescope in 1995. Further VLBA observations of NGC 4258 allowed astronomers to calculate an extremely accurate distance to that galaxy last year. "We're excited to find this phenomenon in a second galaxy, but we're also tantalized by the evidence that these masers respond to variations of the central engine," Gallimore said. In order to amplify radio signals, masers, like their visible-light counterparts, lasers, require a source of energy, called the pumping energy. The scientists believe the masers in NGC 1068 get that pumping energy from a highly-energetic, superhot disk of material that is being pulled into the black hole. That disk, called an accretion disk, emits X-rays that the astronomers think start a chain of events that powers the masers. Such accretion disks can be unstable, dramatically changing their energy output from time to time. "When the accretion disk puts out more energy, the masers should brighten, and when it puts out less energy, they should get fainter. If the accretion disk gets too bright, however, water molecules are destroyed and the masers turn off. We think that's what we're seeing in this galaxy," Gallimore said. "We want to watch this in the future to learn more, not only about the masers, but also about the accretion disk itself," he said. The strongest evidence that the masers are responding to variations in the output of the central engine came from watching variations in the brightness of masers on opposite sides of the water molecule disk. The masers on both sides of the molecular disk, some 5 light-years across, brightened within about two weeks of each other. "If this were caused by something within that molecular disk itself, it would take about 10,000 years to affect both sides of the disk, because of the orbital times involved. However, both sides of the disk are the same distance from the central engine, so they can both respond to the central engine simultaneously," Gallimore explained. The black hole at NGC 1068's center, the scientists say, is about 10 million times more massive than the Sun. NGC 1068 also is known as Messier 77 (M77), one of the objects listed in French astronomer Charles Messier's catalog of non-stellar objects. First observed in 1780, it appeared in the version of Messier's catalog published in 1781. In 1914, Lowell Observatory astronomer Vesto Slipher measured the Doppler shift in the galaxy's light, showing that the galaxy is receding from Earth at a speed of about 1,100 kilometers per second. The galaxy's water masers, which amplify radio signals at a frequency of 22 GHz, were discovered in 1984. The galaxy is visible in moderate-sized amateur telescopes. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

A Case Study of an Experiment Using Streaming of Lectures in Teaching Engineering Mathematics

ERIC Educational Resources Information Center

Fredriksen, Helge

2015-01-01

To support the possibility of taking an online engineering degree programme, Narvik University College has chosen to facilitate a streaming service of all lectures conducted by the college. At the Bodø college campus, in the academic year of 2012/2013, these online lectures were used as a central component in a didactic innovation project. The aim…
Development of a spinning wave heat engine

NASA Technical Reports Server (NTRS)

Zinn, B. T.; Powell, E. A.; Hubbartt, J. E.

1982-01-01

A theoretical analysis and an experimental investigation were conducted to assess the feasibility of developing a spinning wave heat engine. Such as engine would utilize a large amplitude traveling acoustic wave rotating around a cylindrica chamber, and it should not suffer from the inefficiency, noise, and intermittent thrust which characterizes pulse jet engines. The objective of this investigation was to determine whether an artificially driven large amplitude spinning transverse wave could induce a steady flow of air through the combustion chamber under cold flow conditions. In the theoretical analysis the Maslen and Moore perturbation technique was extended to study flat cylinders (pancake geometry) with completely open side walls and a central opening. In the parallel experimental study, a test moel was used to determine resonant frequencies and radial pressure distributions, as well as oscillatory and steady flow velocities at the inner and outer peripheries. The experimental frequency was nearly the same as the theoretical acoustic value for a model of the same outer diameter but without a central hole. Although the theoretical analysis did not predict a steady velocity component, simulaneous measurements of hotwire and microphone responses have shown that the spinning wave pumps a mean flow radially outward through the cavity.
Update on the Department of the Navy Systems Engineering Career Competency Model Acquisition Activities

DTIC Science & Technology

2016-04-30

Model Acquisition Activities Clifford Whitcomb, Systems Engineering Professor, NPS Corina White, Systems Engineering Research Associate, NPS...Engineering Acquisition Activities Karen Holness, Assistant Professor, NPS Update on the Department of the Navy Systems Engineering Career Competency Model ...Career Competency Model Clifford A. Whitcomb—is a Professor in the Systems Engineering Department at the Naval Postgraduate School, in Monterey, CA
Numerical evaluation of single central jet for turbine disk cooling

NASA Astrophysics Data System (ADS)

Subbaraman, M. R.; Hadid, A. H.; McConnaughey, P. K.

The cooling arrangement of the Space Shuttle Main Engine High Pressure Oxidizer Turbopump (HPOTP) incorporates two jet rings, each of which produces 19 high-velocity coolant jets. At some operating conditions, the frequency of excitation associated with the 19 jets coincides with the natural frequency of the turbine blades, contributing to fatigue cracking of blade shanks. In this paper, an alternate turbine disk cooling arrangement, applicable to disk faces of zero hub radius, is evaluated, which consists of a single coolant jet impinging at the center of the turbine disk. Results of the CFD analysis show that replacing the jet ring with a single central coolant jet in the HPOTP leads to an acceptable thermal environment at the disk rim. Based on the predictions of flow and temperature fields for operating conditions, the single central jet cooling system was recommended for implementation into the development program of the Technology Test Bed Engine at NASA Marshall Space Flight Center.
Advanced Turbine Technology Applications Project (ATTAP)

NASA Technical Reports Server (NTRS)

1989-01-01

ATTAP activities during the past year were highlighted by an extensive materials assessment, execution of a reference powertrain design, test-bed engine design and development, ceramic component design, materials and component characterization, ceramic component process development and fabrication, component rig design and fabrication, test-bed engine fabrication, and hot gasifier rig and engine testing. Materials assessment activities entailed engine environment evaluation of domestically supplied radial gasifier turbine rotors that were available at the conclusion of the Advanced Gas Turbine (AGT) Technology Development Project as well as an extensive survey of both domestic and foreign ceramic suppliers and Government laboratories performing ceramic materials research applicable to advanced heat engines. A reference powertrain design was executed to reflect the selection of the AGT-5 as the ceramic component test-bed engine for the ATTAP. Test-bed engine development activity focused on upgrading the AGT-5 from a 1038 C (1900 F) metal engine to a durable 1371 C (2500 F) structural ceramic component test-bed engine. Ceramic component design activities included the combustor, gasifier turbine static structure, and gasifier turbine rotor. The materials and component characterization efforts have included the testing and evaluation of several candidate ceramic materials and components being developed for use in the ATTAP. Ceramic component process development and fabrication activities were initiated for the gasifier turbine rotor, gasifier turbine vanes, gasifier turbine scroll, extruded regenerator disks, and thermal insulation. Component rig development activities included combustor, hot gasifier, and regenerator rigs. Test-bed engine fabrication activities consisted of the fabrication of an all-new AGT-5 durability test-bed engine and support of all engine test activities through instrumentation/build/repair. Hot gasifier rig and test-bed engine testing activities were performed.
The blood-brain barrier: an engineering perspective

PubMed Central

Wong, Andrew D.; Ye, Mao; Levy, Amanda F.; Rothstein, Jeffrey D.; Bergles, Dwight E.; Searson, Peter C.

2013-01-01

It has been more than 100 years since Paul Ehrlich reported that various water-soluble dyes injected into the circulation did not enter the brain. Since Ehrlich's first experiments, only a small number of molecules, such as alcohol and caffeine have been found to cross the blood-brain barrier, and this selective permeability remains the major roadblock to treatment of many central nervous system diseases. At the same time, many central nervous system diseases are associated with disruption of the blood-brain barrier that can lead to changes in permeability, modulation of immune cell transport, and trafficking of pathogens into the brain. Therefore, advances in our understanding of the structure and function of the blood-brain barrier are key to developing effective treatments for a wide range of central nervous system diseases. Over the past 10 years it has become recognized that the blood-brain barrier is a complex, dynamic system that involves biomechanical and biochemical signaling between the vascular system and the brain. Here we reconstruct the structure, function, and transport properties of the blood-brain barrier from an engineering perspective. New insight into the physics of the blood-brain barrier could ultimately lead to clinical advances in the treatment of central nervous system diseases. PMID:24009582
Functionalized carbon nanotubes for potential medicinal applications.

PubMed

Zhang, Yi; Bai, Yuhong; Yan, Bing

2010-06-01

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

NASA Technical Reports Server (NTRS)

Vaidyanathan, Raj

2004-01-01

The following summarizes the activities performed under NASA grant NAG10-323 from September 1, 2002 through September 30, 2004 at the. Univ ersity of Central Florida. A version of this has already been submitt ed for publication in the international journal Swart Materials and S tructures in December 2004. Additionally, a version of this has alrea dy appeared in print in Advances in Cryogenic Engineering, American Institute of Physics, (2004) 50A 26-3; in an article entitled "A Shape Memory Alloy Based Cryogenic Thermal Conduction Switch" by V.B. Krish nan. J.D. Singh. T.R. Woodruff. W.U. Notardonato and R. Vaidyanathan (article is attached at the end of this report).
DOE Office of Scientific and Technical Information (OSTI.GOV)

Kok, Koen; Widergren, Steve

Secure, Clean and Efficient Energy is one of the great societal challenges of our time. Electricity as a sustainable energy carrier plays a central role in the most effective transition scenarios towards sustainability. To harness this potential, the current electricity infrastructure needs to be rigorously re-engineered into an integrated and intelligent electricity system: the smart grid. Key elements of the smart grid vision are the coordination mechanisms. In such a system, vast numbers of devices, currently just passively connected to the grid, will become actively involved in system-wide and local coordination tasks. In this light, transactive energy (TE) is emergingmore » as a strong contender for orchestrating the coordinated operation of so many devices.« less
How Shapley Lectures have Enriched a Small University in the Heart of Michigan

NASA Astrophysics Data System (ADS)

Reed, L.

1998-05-01

Saginaw Valley State University SVSU, is tucked in the industrial heartland of central Michigan. Our students can best be described as non-traditional in the sense that many are employed full - or part-time while working to upgrade or complete a degree. Our Physics Department is a small but active member of the College of Science, Engineering and Technology. Many Shapley lecturers have visited us over the years and each has inspired our students, faculty and community to think about the universe in a new and exciting way. I will share some of the feed back we have received about the program and emphasize its continuing importance to smaller institutions like SVSU
Distributed Control Architecture for Gas Turbine Engine. Chapter 4

NASA Technical Reports Server (NTRS)

Culley, Dennis; Garg, Sanjay

2009-01-01

The transformation of engine control systems from centralized to distributed architecture is both necessary and enabling for future aeropropulsion applications. The continued growth of adaptive control applications and the trend to smaller, light weight cores is a counter influence on the weight and volume of control system hardware. A distributed engine control system using high temperature electronics and open systems communications will reverse the growing trend of control system weight ratio to total engine weight and also be a major factor in decreasing overall cost of ownership for aeropropulsion systems. The implementation of distributed engine control is not without significant challenges. There are the needs for high temperature electronics, development of simple, robust communications, and power supply for the on-board electronics.
Army Corps of Engineers: Water Resource Authorizations, Appropriations, and Activities

DTIC Science & Technology

2017-02-27

of Engineers: Water Resource Authorizations, Appropriations, and Activities Congressional Research Service Summary The U.S. Army Corps of......Engineers: Water Resource Authorizations, Appropriations, and Activities Congressional Research Service 1 Army Corps of Engineers The U.S. Army Corps of
Improving student learning in calculus through applications

NASA Astrophysics Data System (ADS)

Young, C. Y.; Georgiopoulos, M.; Hagen, S. C.; Geiger, C. L.; Dagley-Falls, M. A.; Islas, A. L.; Ramsey, P. J.; Lancey, P. M.; Straney, R. A.; Forde, D. S.; Bradbury, E. E.

2011-07-01

Nationally only 40% of the incoming freshmen Science, Technology, Engineering and Mathematics (STEM) majors are successful in earning a STEM degree. The University of Central Florida (UCF) EXCEL programme is a National Science Foundation funded STEM Talent Expansion Programme whose goal is to increase the number of UCF STEM graduates. One of the key requirements for STEM majors is a strong foundation in Calculus. To improve student learning in calculus, the EXCEL programme developed two special courses at the freshman level called Applications of Calculus I (Apps I) and Applications of Calculus II (Apps II). Apps I and II are one-credit classes that are co-requisites for Calculus I and II. These classes are teams taught by science and engineering professors whose goal is to demonstrate to students where the calculus topics they are learning appear in upper level science and engineering classes as well as how faculty use calculus in their STEM research programmes. This article outlines the process used in producing the educational materials for the Apps I and II courses, and it also discusses the assessment results pertaining to this specific EXCEL activity. Pre- and post-tests conducted with experimental and control groups indicate significant improvement in student learning in Calculus II as a direct result of the application courses.
Engineering of vault nanocapsules with enzymatic and fluorescent properties

PubMed Central

Kickhoefer, Valerie A.; Garcia, Yvette; Mikyas, Yeshi; Johansson, Erik; Zhou, Jing C.; Raval-Fernandes, Sujna; Minoofar, Payam; Zink, Jeffrey I.; Dunn, Bruce; Stewart, Phoebe L.; Rome, Leonard H.

2005-01-01

One of the central issues facing the emerging field of nanotechnology is cellular compatibility. Nanoparticles have been proposed for diagnostic and therapeutic applications, including drug delivery, gene therapy, biological sensors, and controlled catalysis. Viruses, liposomes, peptides, and synthetic and natural polymers have been engineered for these applications, yet significant limitations continue to prevent their use. Avoidance of the body's natural immune system, lack of targeting specificity, and the inability to control packaging and release are remaining obstacles. We have explored the use of a naturally occurring cellular nanoparticle known as the vault, which is named for its morphology with multiple arches reminiscent of cathedral ceilings. Vaults are 13-MDa ribonucleoprotein particles with an internal cavity large enough to sequester hundreds of proteins. Here, we report a strategy to target and sequester biologically active materials within the vault cavity. Attachment of a vault-targeting peptide to two proteins, luciferase and a variant of GFP, resulted in their sequestration within the vault cavity. The targeted proteins confer enzymatic and fluorescent properties on the recombinant vaults, both of which can be detected by their emission of light. The modified vaults are compatible with living cells. The ability to engineer vault particles with designed properties and functionalities represents an important step toward development of a biocompatible nanocapsule. PMID:15753293
Engineering of vault nanocapsules with enzymatic and fluorescent properties.

PubMed

Kickhoefer, Valerie A; Garcia, Yvette; Mikyas, Yeshi; Johansson, Erik; Zhou, Jing C; Raval-Fernandes, Sujna; Minoofar, Payam; Zink, Jeffrey I; Dunn, Bruce; Stewart, Phoebe L; Rome, Leonard H

2005-03-22

One of the central issues facing the emerging field of nanotechnology is cellular compatibility. Nanoparticles have been proposed for diagnostic and therapeutic applications, including drug delivery, gene therapy, biological sensors, and controlled catalysis. Viruses, liposomes, peptides, and synthetic and natural polymers have been engineered for these applications, yet significant limitations continue to prevent their use. Avoidance of the body's natural immune system, lack of targeting specificity, and the inability to control packaging and release are remaining obstacles. We have explored the use of a naturally occurring cellular nanoparticle known as the vault, which is named for its morphology with multiple arches reminiscent of cathedral ceilings. Vaults are 13-MDa ribonucleoprotein particles with an internal cavity large enough to sequester hundreds of proteins. Here, we report a strategy to target and sequester biologically active materials within the vault cavity. Attachment of a vault-targeting peptide to two proteins, luciferase and a variant of GFP, resulted in their sequestration within the vault cavity. The targeted proteins confer enzymatic and fluorescent properties on the recombinant vaults, both of which can be detected by their emission of light. The modified vaults are compatible with living cells. The ability to engineer vault particles with designed properties and functionalities represents an important step toward development of a biocompatible nanocapsule.
The necessity of a theory of biology for tissue engineering: metabolism-repair systems.

PubMed

Ganguli, Suman; Hunt, C Anthony

2004-01-01

Since there is no widely accepted global theory of biology, tissue engineering and bioengineering lack a theoretical understanding of the systems being engineered. By default, tissue engineering operates with a "reductionist" theoretical approach, inherited from traditional engineering of non-living materials. Long term, that approach is inadequate, since it ignores essential aspects of biology. Metabolism-repair systems are a theoretical framework which explicitly represents two "functional" aspects of living organisms: self-repair and self-replication. Since repair and replication are central to tissue engineering, we advance metabolism-repair systems as a potential theoretical framework for tissue engineering. We present an overview of the framework, and indicate directions to pursue for extending it to the context of tissue engineering. We focus on biological networks, both metabolic and cellular, as one such direction. The construction of these networks, in turn, depends on biological protocols. Together these concepts may help point the way to a global theory of biology appropriate for tissue engineering.
DRUMS: a human disease related unique gene mutation search engine.

PubMed

Li, Zuofeng; Liu, Xingnan; Wen, Jingran; Xu, Ye; Zhao, Xin; Li, Xuan; Liu, Lei; Zhang, Xiaoyan

2011-10-01

With the completion of the human genome project and the development of new methods for gene variant detection, the integration of mutation data and its phenotypic consequences has become more important than ever. Among all available resources, locus-specific databases (LSDBs) curate one or more specific genes' mutation data along with high-quality phenotypes. Although some genotype-phenotype data from LSDB have been integrated into central databases little effort has been made to integrate all these data by a search engine approach. In this work, we have developed disease related unique gene mutation search engine (DRUMS), a search engine for human disease related unique gene mutation as a convenient tool for biologists or physicians to retrieve gene variant and related phenotype information. Gene variant and phenotype information were stored in a gene-centred relational database. Moreover, the relationships between mutations and diseases were indexed by the uniform resource identifier from LSDB, or another central database. By querying DRUMS, users can access the most popular mutation databases under one interface. DRUMS could be treated as a domain specific search engine. By using web crawling, indexing, and searching technologies, it provides a competitively efficient interface for searching and retrieving mutation data and their relationships to diseases. The present system is freely accessible at http://www.scbit.org/glif/new/drums/index.html. © 2011 Wiley-Liss, Inc.
Virtual engine management simulator for educational purposes

NASA Astrophysics Data System (ADS)

Drosescu, R.

2017-10-01

This simulator was conceived as a software program capable of generating complex control signals, identical to those in the electronic management systems of modern spark ignition or diesel engines. Speed in rpm and engine load percentage defined by throttle opening angle represent the input variables in the simulation program and are graphically entered by two-meter instruments from the simulator central block diagram. The output signals are divided into four categories: synchronization and position of each cylinder, spark pulses for spark ignition engines, injection pulses and, signals for generating the knock window for each cylinder in the case of a spark ignition engine. The simulation program runs in real-time so each signal evolution reflects the real behavior on a physically thermal engine. In this way, the generated signals (ignition or injection pulses) can be used with additionally drivers to control an engine on the test bench.
Performance of a High-Speed Compression-Ignition Engine Using Multiple Orifice Fuel Injection Nozzles

NASA Technical Reports Server (NTRS)

Spanogle, J A; Foster, H H

1930-01-01

This report presents test results obtained at the Langley Memorial Aeronautical Laboratory of the National Advisory Committee for Aeronautics during an investigation to determine the relative performance of a single-cylinder, high-speed, compression-ignition engine when using fuel injection valve nozzles with different numbers, sizes, and directions of round orifices. A spring-loaded, automatic injection valve was used, centrally located at the top of a vertical disk-type combustion chamber formed between horizontally opposed inlet and exhaust valves of a 5 inch by 7 inch engine.
c-MPL provides tumor-targeted T-cell receptor-transgenic T cells with costimulation and cytokine signals.

PubMed

Nishimura, Christopher D; Brenner, Daniel A; Mukherjee, Malini; Hirsch, Rachel A; Ott, Leah; Wu, Meng-Fen; Liu, Hao; Dakhova, Olga; Orange, Jordan S; Brenner, Malcolm K; Lin, Charles Y; Arber, Caroline

2017-12-21

Adoptively transferred T-cell receptor (TCR)-engineered T cells depend on host-derived costimulation and cytokine signals for their full and sustained activation. However, in patients with cancer, both signals are frequently impaired. Hence, we developed a novel strategy that combines both essential signals in 1 transgene by expressing the nonlymphoid hematopoietic growth factor receptor c-MPL (myeloproliferative leukemia), the receptor for thrombopoietin (TPO), in T cells. c-MPL signaling activates pathways shared with conventional costimulatory and cytokine receptor signaling. Thus, we hypothesized that host-derived TPO, present in the tumor microenvironment, or pharmacological c-MPL agonists approved by the US Food and Drug Administration could deliver both signals to c-MPL-engineered TCR-transgenic T cells. We found that c-MPL + polyclonal T cells expand and proliferate in response to TPO, and persist longer after adoptive transfer in immunodeficient human TPO-transgenic mice. In TCR-transgenic T cells, c-MPL activation enhances antitumor function, T-cell expansion, and cytokine production and preserves a central memory phenotype. c-MPL signaling also enables sequential tumor cell killing, enhances the formation of effective immune synapses, and improves antileukemic activity in vivo in a leukemia xenograft model. We identify the type 1 interferon pathway as a molecular mechanism by which c-MPL mediates immune stimulation in T cells. In conclusion, we present a novel immunotherapeutic strategy using c-MPL-enhanced transgenic T cells responding to either endogenously produced TPO (a microenvironment factor in hematologic malignancies) or c-MPL-targeted pharmacological agents. © 2017 by The American Society of Hematology.

Overview of International Thermonuclear Experimental Reactor (ITER) engineering design activities*

NASA Astrophysics Data System (ADS)

Shimomura, Y.

1994-05-01

The International Thermonuclear Experimental Reactor (ITER) [International Thermonuclear Experimental Reactor (ITER) (International Atomic Energy Agency, Vienna, 1988), ITER Documentation Series, No. 1] project is a multiphased project, presently proceeding under the auspices of the International Atomic Energy Agency according to the terms of a four-party agreement among the European Atomic Energy Community (EC), the Government of Japan (JA), the Government of the Russian Federation (RF), and the Government of the United States (US), ``the Parties.'' The ITER project is based on the tokamak, a Russian invention, and has since been brought to a high level of development in all major fusion programs in the world. The objective of ITER is to demonstrate the scientific and technological feasibility of fusion energy for peaceful purposes. The ITER design is being developed, with support from the Parties' four Home Teams and is in progress by the Joint Central Team. An overview of ITER Design activities is presented.
The fuelling of active galactic nuclei

NASA Technical Reports Server (NTRS)

Shlosman, Isaac; Begelman, Mitchell C.; Frank, Julian

1990-01-01

Accretion mechanisms for powering the central engines of active galactic nuclei (AGN) and possible sources of fuel are reviewed. It is a argued that the interstellar matter in the main body of the host galaxy is channeled toward the center, and the problem of angular momentum transport is addressed. Thin accretion disks are not a viable means of delivering fuel to luminous AGN on scales much larger than a parsec because of the long inflow time and effects of self-gravity. There are also serious obstacles to maintaining and regulating geometrically thick, hot accretion flows. The role of nonaxisymmetric perturbations of the gravitational potential on galactic scales and their triggers is emphasized. A unified model is outlined for fueling AGN, in which the inflow on large scales is driven by gravitational torques, and on small scales forms a mildly self-gravitating disk of clouds with inflow driven by magnetic torques or cloud-cloud collisions.
Plac8 links oncogenic mutations to regulation of autophagy and is critical to pancreatic cancer progression

PubMed Central

Kinsey, Conan; Balakrishnan, Vijaya; O’Dell, Michael R.; Huang, Jing Li; Newman, Laurel; Whitney-Miller, Christa L.; Hezel, Aram F.; Land, Hartmut

2014-01-01

Summary Mutations in p53 and RAS potently cooperate in oncogenic transformation and correspondingly these genetic alterations frequently coexist in pancreatic ductal adenocarcinoma (PDA) and other human cancers. Previously we identified a set of genes synergistically activated by combined RAS and p53 mutations as frequent downstream mediators of tumorigenesis. Here, we show that the synergistically activated gene Plac8 is critical for pancreatic cancer growth. Silencing of Plac8 in cell lines suppresses tumor formation by blocking autophagy, a process essential for maintaining metabolic homeostasis in PDA, and genetic inactivation in an engineered mouse model inhibits PDA progression. We show that Plac8 is a critical regulator of the autophagic machinery, localizing to the lysosomal compartment and facilitating lysosome-autophagosome fusion. Plac8 thus provides a mechanistic link between primary oncogenic mutations and the induction of autophagy, a central mechanism of metabolic reprogramming, during PDA progression. PMID:24794439
Optimal CV-22 Centralized Intermediate Repair Facility Locations and Parts Repair

DTIC Science & Technology

2009-06-01

and Reorder Point for TEWS ............................ 36 Table 8. Excel Model for Safety Stock and Reorder Point for FADEC ...Digital Engine Control ( FADEC ) Main Wheel Assembly Blade Fold System Landing Gear Control Panel Drive System Interface Unit Main Landing Gear...Radar 4 Forward Looking Infrared System (FLIR) 4 Tactical Electronic Warfare System (TEWS) 1 Full Authority Digital Engine Control ( FADEC ) 2 Blade
Geomodels of coseismic landslides environments in Central Chile.

NASA Astrophysics Data System (ADS)

Serey, A.; Sepulveda, S. A.; Murphy, W.; Petley, D. N.

2017-12-01

Landslides are a major source of fatalities and damage during strong earthquakes in mountain areas. Detailed geomodels of coseismic landslides environments are essential parts of seismic landslide hazard analyses. The development of a site specific geological model is required, based on consideration of the regional and local geological and geomorphological history and the current ground surface conditions. An engineering geological model is any approximation of the geological conditions, at varying scales, created for the purpose of solving an engineering problem. In our case, the objective is the development of a methodology for earthquake-induced landslide hazard assessment applicable to urban/territorial planning and disaster prevention strategies assessment at a regional scale adapted for the Chilean tectonic conditions. We have developed the only 2 complete inventories of landslides triggered by earthquakes in Chile. The first from the Mw 6.2, shallow crustal Aysén earthquake in 2007. Second one from the Mw 8.8, megathrust subduction Maule earthquake in 2010. From the comparison of these 2 inventories with others from abroad, as well as analysis of large, prehistoric landslide inventories proposed as likely induced by seismic activity we have determined topographic, geomorphological, geological and seismic controlling factors in the occurrence of earthquake-triggered landslides. With the information collected we have defined different environments for generation of coseismic landslides based on the construction of geomodels. As a result we have built several geomodels in the Santiago Cordillera in central Chile (33°S), based upon the San Ramón Fault, a west-vergent reverse fault that outcrops at the edge of Santiago basin recently found to be active and a likely source of seismic activity in the future, with potential of triggering landslides in the Santiago mountain front as well as inland into the Mapocho and Maipo Cordilleran valleys. In conclusion these geomodels are a powerful tool for earthquake-induced landslide hazard assessment. As an implication we can identify landslide-prone areas, distinguish different seismic scenarios and describe related potential hazards, including burial and river damming by large rock slides and rock avalanches.
A Comprehensive Approach to Management of Workplace and Environmental Noise at NASA Lewis Research Center

NASA Technical Reports Server (NTRS)

Cooper, Beth A.

1995-01-01

NASA Lewis Research Center is home to more than 100 experimental research testing facilities and laboratories, including large wind tunnels and engine test cells, which in combination create a varied and complex noise environment. Much of the equipment was manufactured prior to the enactment of legislation limiting product noise emissions or occupational noise exposure. Routine facility maintenance and associated construction also contributes to a noise exposure management responsibility which is equal in magnitude and scope to that of several small industrial companies. The Noise Program, centrally managed within the Office of Environmental Programs at LRC, maintains overall responsibility for hearing conservation, community noise control, and acoustical and noise control engineering. Centralized management of the LRC Noise Program facilitates the timely development and implementation of engineered noise control solutions for problems identified via either the Hearing Conservation of Community Noise Program. The key element of the Lewis Research Center Noise Program, Acoustical and Noise Control Engineering Services, is focused on developing solutions that permanently reduce employee and community noise exposure and maximize research productivity by reducing or eliminating administrative and operational controls and by improving the safety and comfort of the work environment. The Hearing Conservation Program provides noise exposure assessment, medical monitoring, and training for civil servant and contractor employees. The Community Noise Program aims to maintain the support of LRC's neighboring communities while enabling necessary research operations to accomplish their programmatic goals. Noise control engineering capability resides within the Noise Program. The noise control engineering, based on specific exposure limits, is a fundamental consideration throughout the design phase of new test facilities, labs, and office buildings. In summary, the Noise Program addresses hearing conservation, community noise control, and acoustical and noise control engineering.
Alternative Fuels Data Center: Central Ohio Turns Trash Into Natural Gas

Science.gov Websites

electric car. College Students Engineer Efficient Vehicles in EcoCAR 2 Competition Aug. 2, 2014 Photo of a Authority of Central Ohio turns trash into compressed natural gas for fleet fuel. For information about this FuelEconomy.gov. Provided by Maryland Public Television Related Videos Photo of a car Electric Vehicles Charge up
Engineering Encounters: Catch Me if You Can!

ERIC Educational Resources Information Center

Lott, Kimberly; Wallin, Mark; Roghaar, Deborah; Price, Tyson

2013-01-01

A science, technology, engineering, and math (STEM) activity is any activity that integrates the use of science, technology, engineering, and mathematics to solve a problem. Traditionally, STEM activities are highly engaging and may involve competition among student teams. Young children are natural engineers and often times spontaneously build…
Distributed Engine Control Empirical/Analytical Verification Tools

NASA Technical Reports Server (NTRS)

DeCastro, Jonathan; Hettler, Eric; Yedavalli, Rama; Mitra, Sayan

2013-01-01

NASA's vision for an intelligent engine will be realized with the development of a truly distributed control system featuring highly reliable, modular, and dependable components capable of both surviving the harsh engine operating environment and decentralized functionality. A set of control system verification tools was developed and applied to a C-MAPSS40K engine model, and metrics were established to assess the stability and performance of these control systems on the same platform. A software tool was developed that allows designers to assemble easily a distributed control system in software and immediately assess the overall impacts of the system on the target (simulated) platform, allowing control system designers to converge rapidly on acceptable architectures with consideration to all required hardware elements. The software developed in this program will be installed on a distributed hardware-in-the-loop (DHIL) simulation tool to assist NASA and the Distributed Engine Control Working Group (DECWG) in integrating DCS (distributed engine control systems) components onto existing and next-generation engines.The distributed engine control simulator blockset for MATLAB/Simulink and hardware simulator provides the capability to simulate virtual subcomponents, as well as swap actual subcomponents for hardware-in-the-loop (HIL) analysis. Subcomponents can be the communication network, smart sensor or actuator nodes, or a centralized control system. The distributed engine control blockset for MATLAB/Simulink is a software development tool. The software includes an engine simulation, a communication network simulation, control algorithms, and analysis algorithms set up in a modular environment for rapid simulation of different network architectures; the hardware consists of an embedded device running parts of the CMAPSS engine simulator and controlled through Simulink. The distributed engine control simulation, evaluation, and analysis technology provides unique capabilities to study the effects of a given change to the control system in the context of the distributed paradigm. The simulation tool can support treatment of all components within the control system, both virtual and real; these include communication data network, smart sensor and actuator nodes, centralized control system (FADEC full authority digital engine control), and the aircraft engine itself. The DECsim tool can allow simulation-based prototyping of control laws, control architectures, and decentralization strategies before hardware is integrated into the system. With the configuration specified, the simulator allows a variety of key factors to be systematically assessed. Such factors include control system performance, reliability, weight, and bandwidth utilization.
High School Teachers' Conceptions of Engineers and Engineering

ERIC Educational Resources Information Center

Hoh, Yin Kiong

2012-01-01

This paper describes a workshop activity the author has carried out with 80 high school science teachers to enable them to overcome their stereotypical perceptions of engineers and engineering. The activity introduced them to the biographies of prominent women in engineering, and raised their awareness of these female engineers' contributions to…
Design and Engineering Strategies for Synthetic Antimicrobial Peptides

NASA Astrophysics Data System (ADS)

Tossi, Alessandro

Thousands of antimicrobial peptides (AMPs) of prokaryotic, fungal, plant, or animal origin have been identified, and their potential as lead compounds for the design of novel therapeutic agents in the treatment of infection, for stimulating the immune system, or in countering septic shock has been widely recognized. Added to this is their possible use in prophylaxis of infectious diseases for animal or plant protection, for disinfection of surgical instruments or industrial surfaces, and for food preservation among other commercially important applications. Since the early eighties, AMPs have been subject to a vast number of studies aimed at understanding what determines their potency and spectrum of activities against bacterial or fungal pathogens, and at maximizing these while limiting cytotoxic activities toward host cells. Much research has also been directed toward understanding specific mechanisms of action underlying the antimicrobial activity and selectivity, to be able to redesign the peptides for optimal performance. A central theme in the mode of action of many AMPs is their dynamic interaction with biological membranes, which involves various properties of these peptides such as, among others, surface hydrophobicity and polarity, charge, structure, and induced conformational variations. These features are often intimately interconnected so that engineering peptides to independently adjust any one property in particular is not an easy task. However, solid-phase peptide synthesis allows the use of a large repertoire of nonproteinogenic amino acids that can be used in the rational design of peptides to finely tune structural and physicochemical properties and precisely probe structure-function relationships.
Stress, Allostatic Load, Catecholamines, and Other Neurotransmitters in Neurodegenerative Diseases

PubMed Central

2016-01-01

As populations age, the prevalence of geriatric neurodegenerative diseases will increase. These diseases generally are multifactorial, arising from complex interactions among genes, environment, concurrent morbidities, treatments, and time. This essay provides a concept for the pathogenesis of Lewy body diseases such as Parkinson disease, by considering them in the context of allostasis and allostatic load. Allostasis reflects active, adaptive processes that maintain apparent steady states, via multiple, interacting effectors regulated by homeostatic comparators—“homeostats.” Stress can be defined as a condition or state in which a sensed discrepancy between afferent information and a setpoint for response leads to activation of effectors, reducing the discrepancy. “Allostatic load” refers to the consequences of sustained or repeated activation of mediators of allostasis. From the analogy of an idling car, the revolutions per minute of the engine can be maintained at any of a variety of levels (allostatic states). Just as allostatic load (cumulative wear and tear) reflects design and manufacturing variations, byproducts of combustion, and time, eventually leading to engine breakdown, allostatic load in catecholaminergic neurons might eventually lead to Lewy body diseases. Central to the argument is that catecholaminergic neurons leak vesicular contents into the cytoplasm continuously during life and that catecholamines in the neuronal cytoplasm are autotoxic. These neurons therefore depend on vesicular sequestration to limit autotoxicity of cytosolic transmitter. Parkinson disease might be a disease of the elderly because of allostatic load, which depends on genetic predispositions, environmental exposures, repeated stress-related catecholamine release, and time. PMID:22297542
Stress, Allostatic Load, Catecholamines, and Other Neurotransmitters in Neurodegenerative Diseases

PubMed Central

2017-01-01

As populations age, the prevalence of geriatric neurodegenerative diseases will increase. These diseases generally are multifactorial, arising from complex interactions among genes, environment, concurrent morbidities, treatments, and time. This essay provides a concept for the pathogenesis of Lewy body diseases such as Parkinson disease, by considering them in the context of allostasis and allostatic load. Allostasis reflects active, adaptive processes that maintain apparent steady states, via multiple, interacting effectors regulated by homeostatic comparators—“homeostats.” Stress can be defined as a condition or state in which a sensed discrepancy between afferent information and a setpoint for response leads to activation of effectors, reducing the discrepancy. “Allostatic load” refers to the consequences of sustained or repeated activation of mediators of allostasis. From the analogy of an idling car, the revolutions per minute of the engine can be maintained at any of a variety of levels (allostatic states). Just as allostatic load (cumulative wear and tear) reflects design and manufacturing variations, byproducts of combustion, and time, eventually leading to engine breakdown, allostatic load in catecholaminergic neurons might eventually lead to Lewy body diseases. Central to the argument is that catecholaminergic neurons leak vesicular contents into the cytoplasm continuously during life and that catecholamines in the neuronal cytoplasm are autotoxic. These neurons therefore depend on vesicular sequestration to limit autotoxicity of cytosolic transmitter. Parkinson disease might be a disease of the elderly because of allostatic load, which depends on genetic predispositions, environmental exposures, repeated stress-related catecholamine release, and time. PMID:21615193
36 CFR 200.1 - Central organization.

Code of Federal Regulations, 2010 CFR

2010-07-01

... National Forest System lands and management of natural resources within the principle of multiple use and... engineering, forest economics and marketing, watersheds, wildlife and fish habitat, range, recreation and...
Monitoring activities of daily living based on wearable wireless body sensor network.

PubMed

Kańtoch, E; Augustyniak, P; Markiewicz, M; Prusak, D

2014-01-01

With recent advances in microprocessor chip technology, wireless communication, and biomedical engineering it is possible to develop miniaturized ubiquitous health monitoring devices that are capable of recording physiological and movement signals during daily life activities. The aim of the research is to implement and test the prototype of health monitoring system. The system consists of the body central unit with Bluetooth module and wearable sensors: the custom-designed ECG sensor, the temperature sensor, the skin humidity sensor and accelerometers placed on the human body or integrated with clothes and a network gateway to forward data to a remote medical server. The system includes custom-designed transmission protocol and remote web-based graphical user interface for remote real time data analysis. Experimental results for a group of humans who performed various activities (eg. working, running, etc.) showed maximum 5% absolute error compared to certified medical devices. The results are promising and indicate that developed wireless wearable monitoring system faces challenges of multi-sensor human health monitoring during performing daily activities and opens new opportunities in developing novel healthcare services.
Assembling high activity phosphotriesterase composites using hybrid nanoparticle peptide-DNA scaffolded architectures

NASA Astrophysics Data System (ADS)

Breger, Joyce C.; Buckhout-White, Susan; Walper, Scott A.; Oh, Eunkeu; Susumu, Kimihiro; Ancona, Mario G.; Medintz, Igor L.

2017-06-01

Nanoparticle (NP) display potentially offers a new way to both stabilize and, in many cases, enhance enzyme activity over that seen for native protein in solution. However, the large, globular and sometimes multimeric nature of many enzymes limits their ability to attach directly to the surface of NPs, especially when the latter are colloidally stabilized with bulky PEGylated ligands. Engineering extended protein linkers into the enzymes to achieve direct attachment through the PEG surface often detrimentally alters the enzymes catalytic ability. Here, we demonstrate an alternate, hybrid biomaterials-based approach to achieving directed enzyme assembly on PEGylated NPs. We self-assemble a unique architecture consisting of a central semiconductor quantum dot (QD) scaffold displaying controlled ratios of extended peptide-DNA linkers which penetrate through the PEG surface to directly couple enzymes to the QD surface. As a test case, we utilize phosphotriesterase (PTE), an enzyme of bio-defense interest due to its ability to hydrolyze organophosphate nerve agents. Moreover, this unique approach still allows PTE to maintain enhanced activity while also suggesting the ability of DNA to enhance enzyme activity in and of itself.
A GROWTH-RATE INDICATOR FOR COMPTON-THICK ACTIVE GALACTIC NUCLEI

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

Brightman, M.; Baloković, M.; Harrison, F. A.

2016-07-20

Due to their heavily obscured central engines, the growth rate of Compton-thick (CT) active galactic nuclei (AGNs) is difficult to measure. A statistically significant correlation between the Eddington ratio, λ {sub Edd}, and the X-ray power-law index, Γ, observed in unobscured AGNs offers an estimate of their growth rate from X-ray spectroscopy (albeit with large scatter). However, since X-rays undergo reprocessing by Compton scattering and photoelectric absorption when the line of sight to the central engine is heavily obscured, the recovery of the intrinsic Γ is challenging. Here we study a sample of local, predominantly CT megamaser AGNs, where themore » black hole mass, and thus Eddington luminosity, are well known. We compile results of the X-ray spectral fitting of these sources with sensitive high-energy ( E > 10 keV) NuSTAR data, where X-ray torus models, which take into account the reprocessing effects have been used to recover the intrinsic Γ values and X-ray luminosities, L {sub X}. With a simple bolometric correction to L {sub X} to calculate λ {sub Edd}, we find a statistically significant correlation between Γ and λ {sub Edd} ( p = 0.007). A linear fit to the data yields Γ = (0.41 ± 0.18)log{sub 10} λ {sub Edd} + (2.38 ± 0.20), which is statistically consistent with results for unobscured AGNs. This result implies that torus modeling successfully recovers the intrinsic AGN parameters. Since the megamasers have low-mass black holes ( M {sub BH} ≈ 10{sup 6}–10{sup 7} M {sub ⊙}) and are highly inclined, our results extend the Γ– λ {sub Edd} relationship to lower masses and argue against strong orientation effects in the corona, in support of AGN unification. Finally this result supports the use of Γ as a growth-rate indicator for accreting black holes, even for CT AGNs.« less
34 CFR 350.32 - What activities must a Rehabilitation Engineering Research Center conduct?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 34 Education 2 2010-07-01 2010-07-01 false What activities must a Rehabilitation Engineering... DISABILITY AND REHABILITATION RESEARCH PROJECTS AND CENTERS PROGRAM What Rehabilitation Engineering Research Centers Does the Secretary Assist? § 350.32 What activities must a Rehabilitation Engineering Research...
34 CFR 350.32 - What activities must a Rehabilitation Engineering Research Center conduct?

Code of Federal Regulations, 2012 CFR

2012-07-01

... 34 Education 2 2012-07-01 2012-07-01 false What activities must a Rehabilitation Engineering... DISABILITY AND REHABILITATION RESEARCH PROJECTS AND CENTERS PROGRAM What Rehabilitation Engineering Research Centers Does the Secretary Assist? § 350.32 What activities must a Rehabilitation Engineering Research...
34 CFR 350.32 - What activities must a Rehabilitation Engineering Research Center conduct?

Code of Federal Regulations, 2013 CFR

2013-07-01

... 34 Education 2 2013-07-01 2013-07-01 false What activities must a Rehabilitation Engineering... DISABILITY AND REHABILITATION RESEARCH PROJECTS AND CENTERS PROGRAM What Rehabilitation Engineering Research Centers Does the Secretary Assist? § 350.32 What activities must a Rehabilitation Engineering Research...

34 CFR 350.32 - What activities must a Rehabilitation Engineering Research Center conduct?

Code of Federal Regulations, 2011 CFR

2011-07-01

... 34 Education 2 2011-07-01 2010-07-01 true What activities must a Rehabilitation Engineering... DISABILITY AND REHABILITATION RESEARCH PROJECTS AND CENTERS PROGRAM What Rehabilitation Engineering Research Centers Does the Secretary Assist? § 350.32 What activities must a Rehabilitation Engineering Research...
34 CFR 350.32 - What activities must a Rehabilitation Engineering Research Center conduct?

Code of Federal Regulations, 2014 CFR

2014-07-01

... 34 Education 2 2014-07-01 2013-07-01 true What activities must a Rehabilitation Engineering... DISABILITY AND REHABILITATION RESEARCH PROJECTS AND CENTERS PROGRAM What Rehabilitation Engineering Research Centers Does the Secretary Assist? § 350.32 What activities must a Rehabilitation Engineering Research...
Effects of chemical equilibrium on turbine engine performance for various fuels and combustor temperatures

NASA Technical Reports Server (NTRS)

Tran, Donald H.; Snyder, Christopher A.

1992-01-01

A study was performed to quantify the differences in turbine engine performance with and without the chemical dissociation effects for various fuel types over a range of combustor temperatures. Both turbojet and turbofan engines were studied with hydrocarbon fuels and cryogenic, nonhydrocarbon fuels. Results of the study indicate that accuracy of engine performance decreases when nonhydrocarbon fuels are used, especially at high temperatures where chemical dissociation becomes more significant. For instance, the deviation in net thrust for liquid hydrogen fuel can become as high as 20 percent at 4160 R. This study reveals that computer central processing unit (CPU) time increases significantly when dissociation effects are included in the cycle analysis.
48 CFR 836.603 - Collecting data on and appraising firms qualifications.

Code of Federal Regulations, 2012 CFR

2012-10-01

... Construction and Facilities Management, for Central Office; the Director, Office of Construction Management... VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect...
48 CFR 836.603 - Collecting data on and appraising firms qualifications.

Code of Federal Regulations, 2014 CFR

2014-10-01

... Construction and Facilities Management, for Central Office; the Director, Office of Construction Management... VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect...
48 CFR 836.603 - Collecting data on and appraising firms qualifications.

Code of Federal Regulations, 2011 CFR

2011-10-01

... Construction and Facilities Management, for Central Office; the Director, Office of Construction Management... VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect...
48 CFR 836.603 - Collecting data on and appraising firms qualifications.

Code of Federal Regulations, 2013 CFR

2013-10-01

... Construction and Facilities Management, for Central Office; the Director, Office of Construction Management... VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect...
48 CFR 836.603 - Collecting data on and appraising firms qualifications.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Construction and Facilities Management, for Central Office; the Director, Office of Construction Management... VETERANS AFFAIRS SPECIAL CATEGORIES OF CONTRACTING CONSTRUCTION AND ARCHITECT-ENGINEER CONTRACTS Architect...
Electromobility concept for racing cars based on lithium-ion batteries and supercapacitors

NASA Astrophysics Data System (ADS)

Frenzel, B.; Kurzweil, P.; Rönnebeck, H.

For the construction of an all-electric race car, all aspects from engineering design over cost estimation up to the road capability are illuminated. From the most promising batteries for electric vehicle propulsion, the state-of-the art and commercial availability of lithium-ion secondary batteries is critically discussed with respect to cycle-life and unfavorable charge-discharge conditions. A market-overview is given with respect to a small electric car. Different combinations of electric motors and a recuperation system have been investigated. Weight aspects of central drive systems were considered and compared with decentralized wheel-hub drives. As a result, a centralized high-speed drive train based on a permanent-magnet synchronous engine with high-energy magnets seems to be superior due to limited space for assembly.
Using Notable Women in Environmental Engineering to Dispel Misperceptions of Engineers

ERIC Educational Resources Information Center

Hoh, Yin Kiong

2009-01-01

This paper describes an activity the author has carried out with 72 high school science teachers to enable them to overcome their stereotypical perceptions of engineers. The activity introduced them to notable women in environmental engineering, and raised their awareness of these female engineers' contributions to engineering and society. The…
Anatomy and evolution of database search engines-a central component of mass spectrometry based proteomic workflows.

PubMed

Verheggen, Kenneth; Raeder, Helge; Berven, Frode S; Martens, Lennart; Barsnes, Harald; Vaudel, Marc

2017-09-13

Sequence database search engines are bioinformatics algorithms that identify peptides from tandem mass spectra using a reference protein sequence database. Two decades of development, notably driven by advances in mass spectrometry, have provided scientists with more than 30 published search engines, each with its own properties. In this review, we present the common paradigm behind the different implementations, and its limitations for modern mass spectrometry datasets. We also detail how the search engines attempt to alleviate these limitations, and provide an overview of the different software frameworks available to the researcher. Finally, we highlight alternative approaches for the identification of proteomic mass spectrometry datasets, either as a replacement for, or as a complement to, sequence database search engines. © 2017 Wiley Periodicals, Inc.
Multi-cylinder hot gas engine

DOEpatents

Corey, John A.

1985-01-01

A multi-cylinder hot gas engine having an equal angle, V-shaped engine block in which two banks of parallel, equal length, equally sized cylinders are formed together with annular regenerator/cooler units surrounding each cylinder, and wherein the pistons are connected to a single crankshaft. The hot gas engine further includes an annular heater head disposed around a central circular combustor volume having a new balanced-flow hot-working-fluid manifold assembly that provides optimum balanced flow of the working fluid through the heater head working fluid passageways which are connected between each of the cylinders and their respective associated annular regenerator units. This balanced flow provides even heater head temperatures and, therefore, maximum average working fluid temperature for best operating efficiency with the use of a single crankshaft V-shaped engine block.
ATP citrate lyase mediated cytosolic acetyl-CoA biosynthesis increases mevalonate production in Saccharomyces cerevisiae

DOE PAGES

Rodriguez, Sarah; Denby, Charles M.; Van Vu, T.; ...

2016-03-03

With increasing concern about the environmental impact of a petroleum based economy, focus has shifted towards greener production strategies including metabolic engineering of microbes for the conversion of plant-based feedstocks to second generation biofuels and industrial chemicals. Saccharomyces cerevisiae is an attractive host for this purpose as it has been extensively engineered for production of various fuels and chemicals. Many of the target molecules are derived from the central metabolite and molecular building block, acetyl-CoA. To date, it has been difficult to engineer S. cerevisiae to continuously convert sugars present in biomass-based feedstocks to acetyl-CoA derived products due to intrinsicmore » physiological constraints—in respiring cells, the precursor pyruvate is directed away from the endogenous cytosolic acetyl-CoA biosynthesis pathway towards the mitochondria, and in fermenting cells pyruvate is directed towards the byproduct ethanol. In this study we incorporated an alternative mode of acetyl-CoA biosynthesis mediated by ATP citrate lyase (ACL) that may obviate such constraints. We characterized the activity of several heterologously expressed ACLs in crude cell lysates, and found that ACL from Aspergillus nidulans demonstrated the highest activity. We employed a push/pull strategy to shunt citrate towards ACL by deletion of the mitochondrial NAD+-dependent isocitrate dehydrogenase (IDH1) and engineering higher flux through the upper mevalonate pathway. We demonstrated that combining the two modifications increases accumulation of mevalonate pathway intermediates, and that both modifications are required to substantially increase production. Finally, we incorporated a block strategy by replacing the native ERG12 (mevalonate kinase) promoter with the copper-repressible CTR3 promoter to maximize accumulation of the commercially important molecule mevalonate. In conclusion, by combining the push/pull/block strategies, we significantly improved mevalonate production. We anticipate that this strategy can be used to improve the efficiency with which industrial strains of S. cerevisiae convert feedstocks to acetyl-CoA derived fuels and chemicals.« less
ATP citrate lyase mediated cytosolic acetyl-CoA biosynthesis increases mevalonate production in Saccharomyces cerevisiae

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

Rodriguez, Sarah; Denby, Charles M.; Van Vu, T.

With increasing concern about the environmental impact of a petroleum based economy, focus has shifted towards greener production strategies including metabolic engineering of microbes for the conversion of plant-based feedstocks to second generation biofuels and industrial chemicals. Saccharomyces cerevisiae is an attractive host for this purpose as it has been extensively engineered for production of various fuels and chemicals. Many of the target molecules are derived from the central metabolite and molecular building block, acetyl-CoA. To date, it has been difficult to engineer S. cerevisiae to continuously convert sugars present in biomass-based feedstocks to acetyl-CoA derived products due to intrinsicmore » physiological constraints—in respiring cells, the precursor pyruvate is directed away from the endogenous cytosolic acetyl-CoA biosynthesis pathway towards the mitochondria, and in fermenting cells pyruvate is directed towards the byproduct ethanol. In this study we incorporated an alternative mode of acetyl-CoA biosynthesis mediated by ATP citrate lyase (ACL) that may obviate such constraints. We characterized the activity of several heterologously expressed ACLs in crude cell lysates, and found that ACL from Aspergillus nidulans demonstrated the highest activity. We employed a push/pull strategy to shunt citrate towards ACL by deletion of the mitochondrial NAD+-dependent isocitrate dehydrogenase (IDH1) and engineering higher flux through the upper mevalonate pathway. We demonstrated that combining the two modifications increases accumulation of mevalonate pathway intermediates, and that both modifications are required to substantially increase production. Finally, we incorporated a block strategy by replacing the native ERG12 (mevalonate kinase) promoter with the copper-repressible CTR3 promoter to maximize accumulation of the commercially important molecule mevalonate. In conclusion, by combining the push/pull/block strategies, we significantly improved mevalonate production. We anticipate that this strategy can be used to improve the efficiency with which industrial strains of S. cerevisiae convert feedstocks to acetyl-CoA derived fuels and chemicals.« less
Product Lifecycle Management and the Quest for Sustainable Space Explorations

NASA Technical Reports Server (NTRS)

Caruso, Pamela W.; Dumbacher, Daniel L.

2010-01-01

Product Lifecycle Management (PLM) is an outcome of lean thinking to eliminate waste and increase productivity. PLM is inextricably tied to the systems engineering business philosophy, coupled with a methodology by which personnel, processes and practices, and information technology combine to form an architecture platform for product design, development, manufacturing, operations, and decommissioning. In this model, which is being implemented by the Engineering Directorate at the National Aeronautics and Space Administration's (NASA's) Marshall Space Flight Center, total lifecycle costs are important variables for critical decision-making. With the ultimate goal to deliver quality products that meet or exceed requirements on time and within budget, PLM is a powerful concept to shape everything from engineering trade studies and testing goals, to integrated vehicle operations and retirement scenarios. This paper will demonstrate how the Engineering Directorate is implementing PLM as part of an overall strategy to deliver safe, reliable, and affordable space exploration solutions. It has been 30 years since the United States fielded the Space Shuttle. The next generation space transportation system requires a paradigm shift such that digital tools and knowledge management, which are central elements of PLM, are used consistently to maximum effect. The outcome is a better use of scarce resources, along with more focus on stakeholder and customer requirements, as a new portfolio of enabling tools becomes second nature to the workforce. This paper will use the design and manufacturing processes, which have transitioned to digital-based activities, to show how PLM supports the comprehensive systems engineering and integration function. It also will go through a launch countdown scenario where an anomaly is detected to show how the virtual vehicle created from paperless processes will help solve technical challenges and improve the likelihood of launching on schedule, with less hands-on labor needed for processing and troubleshooting.
Regulation of EPS production in Lactobacillus casei LC2W through metabolic engineering.

PubMed

Li, N; Huang, Y; Liu, Z; You, C; Guo, B

2015-12-01

Lactobacillus casei LC2W is an exopolysaccharide(EPS)-producing strain with probiotic effects. The low efficiency and unclear regulation mechanism of EPS biosynthesis have become main constraints for its application in food industry. To investigate the major rate-limiting factors of EPS biosynthesis and to improve its yield, metabolic engineering was applied to this strain. Eight relevant genes related to central metabolism, sugar-nucleotides supply, glycosyltransferase and cofactor engineering were cloned and overexpressed. The results suggested that nox, pfk, rfbB and galT genes were the largest contributors to EPS biosynthesis in this study, which elevated EPS yield by 46·0, 20, 17·4 and 19·6% respectively. Notably, under aerobic condition which was not a suitable condition for lactobacilli to grow in, recombinant strain LC-nox achieved the highest EPS yield of 263·7 mg l(-1) , which was increased by 75% compared to that of the starting strain. The oxygen stress was excluded since the phenomenon was not observed in the control strain under the same condition. Therefore, it was probably that higher NADH oxidase activity led to a decreased NADH availability and reduced lactate concentration, which resulted in the elevation of EPS yield. This study contributed to the understanding of EPS biosynthesis in Lact. casei through metabolic engineering and provided a starting point for introducing cofactor engineering into this strain. Overexpression of NADH oxidase was found to have a most significant effect on the EPS production. It is the first report that EPS could be accumulated to such a high level under aerobic condition in lactobacilli. Our results provided a novel strategy for the improvement of EPS production in lactic acid bacteria. © 2015 The Society for Applied Microbiology.
T Cell Receptor Engineering and Analysis Using the Yeast Display Platform

PubMed Central

Smith, Sheena N.; Harris, Daniel T.; Kranz, David M.

2017-01-01

The αβ heterodimeric T cell receptor (TCR) recognizes peptide antigens that are transported to the cell surface as a complex with a protein encoded by the major histocompatibility complex (MHC). T cells thus evolved a strategy to sense these intracellular antigens, and to respond either by eliminating the antigen-presenting cell (e.g. a virus-infected cell) or by secreting factors that recruit the immune system to the site of the antigen. The central role of the TCR in the binding of antigens as peptide-MHC (pepMHC) ligands has now been studied thoroughly. Interestingly, despite their exquisite sensitivity (e.g. T cell activation by as few as 1 to 3 pepMHC complexes on a single target cell), TCRs are known to have relatively low affinities for pepMHC, with KD values in the micromolar range. There has been interest in engineering the affinity of TCRs in order to use this class of molecules in ways similar to now done with antibodies. By doing so, it would be possible to harness the potential of TCRs as therapeutics against a much wider array of antigens that include essentially all intracellular targets. To engineer TCRs, and to analyze their binding features more rapidly, we have used a yeast display system as a platform. Expression and engineering of a single-chain form of the TCR, analogous to scFv fragments from antibodies, allow the TCR to be affinity matured with a variety of possible pepMHC ligands. In addition, the yeast display platform allows one to rapidly generate TCR variants with diverse binding affinities and to analyze specificity and affinity without the need for purification of soluble forms of the TCRs. The present chapter describes the methods for engineering and analyzing single-chain TCRs using yeast display. PMID:26060072
Architecturing hierarchical function layers on self-assembled viral templates as 3D nano-array electrodes for integrated Li-ion microbatteries.

PubMed

Liu, Yihang; Zhang, Wei; Zhu, Yujie; Luo, Yanting; Xu, Yunhua; Brown, Adam; Culver, James N; Lundgren, Cynthia A; Xu, Kang; Wang, Yuan; Wang, Chunsheng

2013-01-09

This work enables an elegant bottom-up solution to engineer 3D microbattery arrays as integral power sources for microelectronics. Thus, multilayers of functional materials were hierarchically architectured over tobacco mosaic virus (TMV) templates that were genetically modified to self-assemble in a vertical manner on current-collectors, so that optimum power and energy densities accompanied with excellent cycle-life could be achieved on a minimum footprint. The resultant microbattery based on self-aligned LiFePO(4) nanoforests of shell-core-shell structure, with precise arrangement of various auxiliary material layers including a central nanometric metal core as direct electronic pathway to current collector, delivers excellent energy density and stable cycling stability only rivaled by the best Li-ion batteries of conventional configurations, while providing rate performance per foot-print and on-site manufacturability unavailable from the latter. This approach could open a new avenue for microelectromechanical systems (MEMS) applications, which would significantly benefit from the concept that electrochemically active components be directly engineered and fabricated as an integral part of the integrated circuit (IC).
The Philosophical and Pedagogical Underpinnings of Active Learning in Engineering Education

ERIC Educational Resources Information Center

Christie, Michael; de Graaff, Erik

2017-01-01

In this paper the authors draw on three sequential keynote addresses that they gave at Active Learning in Engineering Education (ALE) workshops in Copenhagen (2012), Caxias do Sol (2014) and San Sebastian (2015). Active Learning in Engineering Education is an informal international network of engineering educators dedicated to improving…
Learning Activity Packets for Auto Mechanics II. Section A--Engine Rebuilding.

ERIC Educational Resources Information Center

Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

Eight learning activity packets (LAPs) are provided for the instructional area of engine rebuilding in the auto mechanics II program. They accompany an instructor's guide available separately. The LAPs outline the study activities and performance tasks for these eight units: (1) engine condition evaluation; (2) engine removal; (3) engine…

Auto Mechanics I. Learning Activity Packets (LAPs). Section C--Engine.

ERIC Educational Resources Information Center

Oklahoma State Board of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

This document contains five learning activity packets (LAPs) that outline the study activities for the "engine" instructional area for an Auto Mechanics I course. The five LAPs cover the following topics: basic engine principles, cooling system, engine lubrication system, exhaust system, and fuel system. Each LAP contains a cover sheet…
Example of International Co-Operation in the Frame of the Project Phare (TEMPUS) in Innovations in Teaching of Environmental Hydrogeology in Engineering Education in the Czech Republic.

ERIC Educational Resources Information Center

Grmela, Arnost; Rapantova, Nadia

The international TEMPUS (Trans-European Co-operating and Mobility Scheme for Higher Education between Central/Eastern Europe and European Union) project lasted from 1995-1997. In the framework of TEMPUS, a material and knowledge background was developed in order to ensure the education of the branch Geological Engineering with specialization in…
PR[superscript 2]EPS: Preparation, Recruitment, Retention and Excellence in the Physical Sciences, Including Engineering. A Report on the 2004, 2005 and 2006 Science Summer Camps

ERIC Educational Resources Information Center

Bachman, Nancy J.; Bischoff, Paul J.; Gallagher, Hugh; Labroo, Sunil; Schaumloffel, John C.

2008-01-01

Now in its fourth year, PR[superscript 2]EPS is a National Science Foundation funded initiative designed to recruit high school students to attend college majoring in the physical sciences, including engineering and secondary science education, and to help ensure their retention within the program until graduation. A central feature of the…
Los Alamos science, Number 14

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

Not Available

1986-01-01

Nine authored articles are included covering: natural heat engine, photoconductivity, the Caribbean Basin, energy in Central America, peat, geothermal energy, and the MANIAC computer. Separate abstracts were prepared for the articles. (DLC)
Methodology discourses as boundary work in the construction of engineering education.

PubMed

Beddoes, Kacey

2014-04-01

Engineering education research is a new field that emerged in the social sciences over the past 10 years. This analysis of engineering education research demonstrates that methodology discourses have played a central role in the construction and development of the field of engineering education, and that they have done so primarily through boundary work. This article thus contributes to science and technology studies literature by examining the role of methodology discourses in an emerging social science field. I begin with an overview of engineering education research before situating the case within relevant bodies of literature on methodology discourses and boundary work. I then identify two methodology discourses--rigor and methodological diversity--and discuss how they contribute to the construction and development of engineering education research. The article concludes with a discussion of how the findings relate to prior research on methodology discourses and boundary work and implications for future research.
About opportunities of the sharing of city infrastructure centralized warmly - and water supply

NASA Astrophysics Data System (ADS)

Zamaleev, M. M.; Gubin, I. V.; Sharapov, V. I.

2017-11-01

It is shown that joint use of engineering infrastructure of centralized heat and water supply of consumers will be the cost-efficient decision for municipal services of the city. The new technology for regulated heating of drinking water in the condenser of steam turbines of combined heat and power plant is offered. Calculation of energy efficiency from application of new technology is executed.
The Structure of Active Galactic Nuclei

NASA Technical Reports Server (NTRS)

Kriss, Gerard A.

1997-01-01

We are continuing our systematic investigation of the nuclear structure of nearby active galactic nuclei (AGN). Upon completion, our study will characterize hypothetical constructs such as narrow-line clouds, obscuring tori, nuclear gas disks. and central black holes with physical measurements for a complete sample of nearby AGN. The major scientific goals of our program are: (1) the morphology of the NLR; (2) the physical conditions and dynamics of individual clouds in the NLR; (3) the structure and physical conditions of the warm reflecting gas; (4) the structure of the obscuring torus; (5) the population and morphology of nuclear disks/tori in AGN; (6) the physical conditions in nuclear disks; and (7) the masses of central black holes in AGN. We will use the Hubble Space Telescope (HST) to obtain high-resolution images and spatially resolved spectra. Far-UV spectroscopy of emission and absorption in the nuclear regions using HST/FOS and the Hopkins Ultraviolet Telescope (HUT) will help establish physical conditions in the absorbing and emitting gas. By correlating the dynamics and physical conditions of the gas with the morphology revealed through our imaging program, we will be able to examine mechanisms for fueling the central engine and transporting angular momentum. The kinematics of the nuclear gas disks may enable us to measure the mass of the central black hole. Contemporaneous X-ray observations using ASCA will further constrain the ionization structure of any absorbing material. Monitoring of variability in the UV and X-ray absorption will be used to determine the location of the absorbing gas, possibly in the outflowing warm reflecting gas, or the broad-line region, or the atmosphere of the obscuring torus. Supporting ground-based observations in the optical, near-IR, imaging polarimetry, and the radio will complete our picture of the nuclear structures. With a comprehensive survey of these characteristics in a complete sample of nearby AGN, our conclusions should be more reliably extended to AGN as a class.
Polarimetric imaging of NGC 1068 at high angular resolution in the near infrared. Direct evidence of an extended nuclear torus

NASA Astrophysics Data System (ADS)

Gratadour, D.; Rouan, D.; Grosset, L.; Boccaletti, A.; Clénet, Y.

2015-09-01

Aims: One of the main observational challenges for investigating the central regions of active galactic nuclei (AGN) at short wavelengths, using high angular resolution, and high contrast observations, is to directly detect the circumnuclear optically thick material hiding the central core emission when viewed edge-on. The lack of direct evidence is limiting our understanding of AGN, and several scenarios have been proposed to cope for the diverse observed aspects of activity in a unified approach. Methods: Observations in the near-infrared spectral range have shown themselves to be powerful for providing essential hints to the characterisation of the unified model ingredients because of the reduced optical depth of the obscuring material. Moreover, it is possible to trace this material through light scattered from the central engine's closest environment, so that polarimetric observations are the ideal tool for distinguishing it from purely thermal and stellar emissions. Results: Here we show strong evidence that there is an extended nuclear torus at the center of NGC 1068 thanks to new adaptive-optics-assisted polarimetric observations in the near-infrared. The orientation of the polarization vectors proves that there is a structured hourglass-shaped bicone and a compact elongated (20 × 60 pc) nuclear structure perpendicular to the bicone axis. The linearly polarized emission in the bicone is dominated by a centro-symmetric pattern, but the central compact region shows a clear deviation from the latter with linear polarization aligned perpendicular to the bicone axis. Figure 2 is available in electronic form at http://www.aanda.orgData obtained with the SPHERE an instrument designed and built by a consortium consisting of IPAG (France), MPIA (Germany), LAM (France), LESIA (France), Laboratoire Lagrange (France), INAF - Osservatorio di Padova (Italy), Observatoire de Genève (Switzerland), ETH Zurich (Switzerland), NOVA (Netherlands), ONERA (France), and ASTRON (Netherlands) in collaboration with ESO.
Physics from Time Variability of the VHE Blazar PKS 2155-304

NASA Astrophysics Data System (ADS)

Barres de Almeida, Ulisses

2010-10-01

Blazars are the principal extragalactic sources of very high energy gamma-ray emission in the Universe. These objects constitute a sub-class of Active Galactic Nuclei whose emission is dominated by Doppler boosted non-thermal radiation from plasma outflow- ing at relativistic speeds from the central engine. This plasma outflow happens in the form of large-scale collimated structures called jets, which can extend for Mpc in length and transport energy from the central engine of the galaxy to the larger scale intergalac- tic medium. Over thirty such sources have been discovered to date by ground-based gamma-ray telescopes such as H.E.S.S., and PKS 2155-304 is the prototypical southern- hemisphere representative of this population of objects. In this thesis we have studied in detail some aspects of the temporal variability of the jet emission from PKS 2155-304, combining coordinated observations across the electro- magnetic spectrum, from optical polarimetric measurements to X-ray and ground-based gamma-ray data. The temporal properties of the dataset allowed us to derive important physical information about the structure and emission mechanisms of the source and put constraints to the location of the sites of VHE emission and particle acceleration within the jet. We have also derived a sensitive statistical measure, called Kolmogorov distance, which we applied to the large outburst observed from PKS 2155-304 in July 2006, to de- rive the most stringent constraints to date on limits for the violation of Lorentz invariance induced by quantum-gravity effects from AGN measurements.
Bimodal Long-lasting Components in Short Gamma-Ray Bursts: Promising Electromagnetic Counterparts to Neutron Star Binary Mergers

NASA Astrophysics Data System (ADS)

Kisaka, Shota; Ioka, Kunihito; Sakamoto, Takanori

2017-09-01

Long-lasting emission of short gamma-ray bursts (GRBs) is crucial to reveal the physical origin of the central engine as well as to detect electromagnetic (EM) counterparts to gravitational waves (GWs) from neutron star binary mergers. We investigate 65 X-ray light curves of short GRBs, which is six times more than previous studies, by combining both Swift/BAT and XRT data. The light curves are found to consist of two distinct components at >5σ with bimodal distributions of luminosity and duration, I.e., extended (with a timescale of ≲103 s) and plateau emission (with a timescale of ≳103 s), which are likely the central engine activities, but not afterglows. The extended emission has an isotropic energy comparable to the prompt emission, while the plateau emission has ˜0.01-1 times this energy. Half (50%) of our sample has both components, while the other half is consistent with having both components. This leads us to conjecture that almost all short GRBs have both the extended and plateau emission. The long-lasting emission can be explained by the jets from black holes with fallback ejecta, and could power macronovae (or kilonovae) like GRB 130603B and GRB 160821B. Based on the observed properties, we quantify the detectability of EM counterparts to GWs, including the plateau emission scattered to the off-axis angle, with CALET/HXM, INTEGRAL/SPI-ACS, Fermi/GBM, MAXI/GSC, Swift/BAT, XRT, the future ISS-Lobster/WFI, Einstein Probe/WXT, and eROSITA.
Relativistic simulations of long-lived reverse shocks in stratified ejecta: the origin of flares in GRB afterglows

NASA Astrophysics Data System (ADS)

Lamberts, A.; Daigne, F.

2018-02-01

The X-ray light curves of the early afterglow phase from gamma-ray bursts (GRBs) present a puzzling variability, including flares. The origin of these flares is still debated, and often associated with a late activity of the central engine. We discuss an alternative scenario where the central engine remains short-lived and flares are produced by the propagation of a long-lived reverse shock in a stratified ejecta. Here we focus on the hydrodynamics of the shock interactions. We perform one-dimensional ultrarelativistic hydrodynamic simulations with different initial internal structure in the GRB ejecta. We use them to extract bolometric light curves and compare with a previous study based on a simplified ballistic model. We find a good agreement between both approaches, with similar slopes and variability in the light curves, but identify several weaknesses in the ballistic model: the density is underestimated in the shocked regions, and more importantly, late shock reflections are not captured. With accurate dynamics provided by our hydrodynamic simulations, we confirm that internal shocks in the ejecta lead to the formation of dense shells. The interaction of the long-lived reverse shock with a dense shell then produces a fast and intense increase of the dissipated power. Assuming that the emission is due to the synchrotron radiation from shock-accelerated electrons, and that the external forward shock is radiatively inefficient, we find that this results in a bright flare in the X-ray light curve, with arrival times, shapes, and duration in agreement with the observed properties of X-ray flares in GRB afterglows.
Bimodal Long-lasting Components in Short Gamma-Ray Bursts: Promising Electromagnetic Counterparts to Neutron Star Binary Mergers

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

Kisaka, Shota; Sakamoto, Takanori; Ioka, Kunihito, E-mail: kisaka@phys.aoyama.ac.jp, E-mail: tsakamoto@phys.aoyama.ac.jp, E-mail: kunihito.ioka@yukawa.kyoto-u.ac.jp

Long-lasting emission of short gamma-ray bursts (GRBs) is crucial to reveal the physical origin of the central engine as well as to detect electromagnetic (EM) counterparts to gravitational waves (GWs) from neutron star binary mergers. We investigate 65 X-ray light curves of short GRBs, which is six times more than previous studies, by combining both Swift /BAT and XRT data. The light curves are found to consist of two distinct components at >5 σ with bimodal distributions of luminosity and duration, i.e., extended (with a timescale of ≲10{sup 3} s) and plateau emission (with a timescale of ≳10{sup 3} s),more » which are likely the central engine activities, but not afterglows. The extended emission has an isotropic energy comparable to the prompt emission, while the plateau emission has ∼0.01–1 times this energy. Half (50%) of our sample has both components, while the other half is consistent with having both components. This leads us to conjecture that almost all short GRBs have both the extended and plateau emission. The long-lasting emission can be explained by the jets from black holes with fallback ejecta, and could power macronovae (or kilonovae) like GRB 130603B and GRB 160821B. Based on the observed properties, we quantify the detectability of EM counterparts to GWs, including the plateau emission scattered to the off-axis angle, with CALET /HXM, INTEGRAL /SPI-ACS, Fermi /GBM, MAXI /GSC, Swift /BAT, XRT, the future ISS-Lobster /WFI, Einstein Probe /WXT, and eROSITA .« less
Executive control systems in the engineering design environment

NASA Technical Reports Server (NTRS)

Hurst, P. W.; Pratt, T. W.

1985-01-01

Executive Control Systems (ECSs) are software structures for the unification of various engineering design application programs into comprehensive systems with a central user interface (uniform access) method and a data management facility. Attention is presently given to the most significant determinations of a research program conducted for 24 ECSs, used in government and industry engineering design environments to integrate CAD/CAE applications programs. Characterizations are given for the systems' major architectural components and the alternative design approaches considered in their development. Attention is given to ECS development prospects in the areas of interdisciplinary usage, standardization, knowledge utilization, and computer science technology transfer.
Corynebacterium glutamicum for Sustainable Bioproduction: From Metabolic Physiology to Systems Metabolic Engineering.

PubMed

Becker, Judith; Gießelmann, Gideon; Hoffmann, Sarah Lisa; Wittmann, Christoph

Since its discovery 60 years ago, Corynebacterium glutamicum has evolved into a workhorse for industrial biotechnology. Traditionally well known for its remarkable capacity to produce amino acids, this Gram-positive soil bacterium, has become a flexible, efficient production platform for various bulk and fine chemicals, materials, and biofuels. The central turnstile of all these achievements is our excellent understanding of its metabolism and physiology. This knowledge base, together with innovative systems metabolic engineering concepts, which integrate systems and synthetic biology into strain engineering, has upgraded C. glutamicum into one of the most successful industrial microorganisms in the world.
Physical activity associate low back pain and intervention program: Review

NASA Astrophysics Data System (ADS)

Ibrahim, Muhamad Aizat Mat; Hasbollah, Hasif Rafidee; Ibrahim, Mohd Asrul Hery; Marican, Nor Dalila; Halim, Muhd Hafzal Abdul; Rashid, Ahmad Faezi Ab.; Yasin, Nurul Hafizah Mohd

2017-10-01

The person who have low back pain often report impaired disability to performance daily activities which passive movement of daily life. The effects of low back pain on daily function of patients can describe as a patients level of disability or reduction in physical function it interferes with the movement of patients for running a daily lives. Therefore, the aim of this study was to conduct a review to examine the relationship between physical activity and low back pain. Besides that, the suggestion prevention program to patient who has low back pain. This systematic review study was used internet to find databases and search engines. Data were collected using Wiley online library, Bioline International, SAGE, Science Direct, NCBI, ProQuest, Biomed central, American Diabetes Association, PLOS One and Springer. The search was performed using keywords of "physical activity", "low back pain", "back pain", "activity level" and "intervention". The study was reviewed the resources and the results were classified in different section The results were classified based on several sections including years of reporting, who were reporting, the origins of articles and their health criteria about physical activity and low back pain. There are positive associate physical activity and low back pain from the systematic review. Future intervention treatment can reduce associate physical activity to low back pain.
Quality Assurance in the Presence of Variability

NASA Astrophysics Data System (ADS)

Lauenroth, Kim; Metzger, Andreas; Pohl, Klaus

Software Product Line Engineering (SPLE) is a reuse-driven development paradigm that has been applied successfully in information system engineering and other domains. Quality assurance of the reusable artifacts of the product line (e.g. requirements, design, and code artifacts) is essential for successful product line engineering. As those artifacts are reused in several products, a defect in a reusable artifact can affect several products of the product line. A central challenge for quality assurance in product line engineering is how to consider product line variability. Since the reusable artifacts contain variability, quality assurance techniques from single-system engineering cannot directly be applied to those artifacts. Therefore, different strategies and techniques have been developed for quality assurance in the presence of variability. In this chapter, we describe those strategies and discuss in more detail one of those strategies, the so called comprehensive strategy. The comprehensive strategy aims at checking the quality of all possible products of the product line and thus offers the highest benefits, since it is able to uncover defects in all possible products of the product line. However, the central challenge for applying the comprehensive strategy is the complexity that results from the product line variability and the large number of potential products of a product line. In this chapter, we present one concrete technique that we have developed to implement the comprehensive strategy that addresses this challenge. The technique is based on model checking technology and allows for a comprehensive verification of domain artifacts against temporal logic properties.
Characterization of In Vitro Engineered Human Adipose Tissues: Relevant Adipokine Secretion and Impact of TNF-α

PubMed Central

Aubin, Kim; Safoine, Meryem; Proulx, Maryse; Audet-Casgrain, Marie-Alice; Côté, Jean-François; Têtu, Félix-André; Roy, Alphonse; Fradette, Julie

2015-01-01

Representative modelling of human adipose tissue functions is central to metabolic research. Tridimensional models able to recreate human adipogenesis in a physiological tissue-like context in vitro are still scarce. We describe the engineering of white adipose tissues reconstructed from their cultured adipose-derived stromal precursor cells. We hypothesize that these reconstructed tissues can recapitulate key functions of AT under basal and pro-inflammatory conditions. These tissues, featuring human adipocytes surrounded by stroma, were stable and metabolically active in long-term cultures (at least 11 weeks). Secretion of major adipokines and growth factors by the reconstructed tissues was determined and compared to media conditioned by human native fat explants. Interestingly, the secretory profiles of the reconstructed adipose tissues indicated an abundant production of leptin, PAI-1 and angiopoietin-1 proteins, while higher HGF levels were detected for the human fat explants. We next demonstrated the responsiveness of the tissues to the pro-inflammatory stimulus TNF-α, as reflected by modulation of MCP-1, NGF and HGF secretion, while VEGF and leptin protein expression did not vary. TNF-α exposure induced changes in gene expression for adipocyte metabolism-associated mRNAs such as SLC2A4, FASN and LIPE, as well as for genes implicated in NF-κB activation. Finally, this model was customized to feature adipocytes representative of progressive stages of differentiation, thereby allowing investigations using newly differentiated or more mature adipocytes. In conclusion, we produced tridimensional tissues engineered in vitro that are able to recapitulate key characteristics of subcutaneous white adipose tissue. These tissues are produced from human cells and their neo-synthesized matrix elements without exogenous or synthetic biomaterials. Therefore, they represent unique tools to investigate the effects of pharmacologically active products on human stromal cells, extracellular matrix and differentiated adipocytes, in addition to compounds modulating adipogenesis from precursor cells. PMID:26367137
Mapping and Engineering Functional Domains of the Assembly Activating Protein of Adeno-Associated Viruses.

PubMed

Tse, Longping V; Moller-Tank, Sven; Meganck, Rita M; Asokan, Aravind

2018-04-25

Adeno-associated viruses (AAV) encode a unique assembly activating protein (AAP) within their genome that is essential for capsid assembly. Studies to date have focused on establishing the role of AAP as a chaperone that mediates stability, nucleolar transport, and assembly of AAV capsid proteins. Here, we map structure-function correlates of AAP using secondary structure analysis followed by deletion and substitutional mutagenesis of specific domains, namely, the hydrophobic N-terminal domain (HR), conserved core (CC), proline-rich region (PRR), threonine/serine rich region (T/S) and basic region (BR). First, we establish that the centrally located PRR and T/S regions are flexible linker domains that can either be deleted completely or replaced by heterologous functional domains that enable ancillary functions such as fluorescent imaging or increased AAP stability. We also demonstrate that the C-terminal BR domains can be substituted with heterologous nuclear or nucleolar localization sequences that display varying ability to support AAV capsid assembly. Further, by replacing the BR domain with immunoglobulin (IgG) Fc domains, we assessed AAP complexation with AAV capsid subunits and demonstrate that the hydrophobic region (HR) and the conserved core (CC) in the AAP N-terminus are the sole determinants for viral protein (VP) recognition. However, VP recognition alone is not sufficient for capsid assembly. Our study sheds light on the modular structure-function correlates of AAP and provides multiple approaches to engineer AAP that might prove useful towards understanding and controlling AAV capsid assembly. Importance: Adeno-associated viruses (AAV) encode a unique assembly activating protein (AAP) within their genome that is essential for capsid assembly. Understanding how AAP acts as a chaperone for viral assembly could help improve efficiency and potentially control this process. Our studies reveal that AAP has a modular architecture, with each module playing a distinct role and can be engineered for carrying out new functions. Copyright © 2018 American Society for Microbiology.
A Method to Constrain Mass and Spin of GRB Black Holes within the NDAF Model

NASA Astrophysics Data System (ADS)

Liu, Tong; Xue, Li; Zhao, Xiao-Hong; Zhang, Fu-Wen; Zhang, Bing

2016-04-01

Black holes (BHs) hide themselves behind various astronomical phenomena and their properties, I.e., mass and spin, are usually difficult to constrain. One leading candidate for the central engine model of gamma-ray bursts (GRBs) invokes a stellar mass BH and a neutrino-dominated accretion flow (NDAF), with the relativistic jet launched due to neutrino-anti-neutrino annihilations. Such a model gives rise to a matter-dominated fireball, and is suitable to interpret GRBs with a dominant thermal component with a photospheric origin. We propose a method to constrain BH mass and spin within the framework of this model and apply the method to the thermally dominant GRB 101219B, whose initial jet launching radius, r0, is constrained from the data. Using our numerical model of NDAF jets, we estimate the following constraints on the central BH: mass MBH ˜ 5-9 M⊙, spin parameter a* ≳ 0.6, and disk mass 3 M⊙ ≲ Mdisk ≲ 4 M⊙. Our results also suggest that the NDAF model is a competitive candidate for the central engine of GRBs with a strong thermal component.
Analysis of pressure buildups taken from fluid level data -Tyler Sands, Central Montana

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

Bishop, D.F.

Pressure buildups taken by fluid level recording prove to be quite usable for formation evaluation in the ''Tyler'' sands of Central Montana. This method provides low cost information with surprising accuracy. The procedures followed in obtaining the data, and the precautions taken in assuring the validity of the data are discussed in the paper. The data proved sufficiently accurate to perform engineering calculations in two separate ''Tyler'' fields. The calculations aided in determination of reservoir parameters, and in one field provided justification for additional development drilling. In another field, the data substantiated the limited reservoir, and development drilling plans weremore » cancelled. The buildup curves illustrated well bore damage in some of the wells and subsequent stimulation of two wells resulted in sustained six-fold and nine-fold increases in producing rates of these wells. This paper illustrates the value of the engineering calculations when applied to carefully gathered field data. The method should have application in other areas with similar producing properties to the ''Tyler'' sands in Central Montana.« less

The Case for Distributed Engine Control in Turbo-Shaft Engine Systems

NASA Technical Reports Server (NTRS)

Culley, Dennis E.; Paluszewski, Paul J.; Storey, William; Smith, Bert J.

2009-01-01

The turbo-shaft engine is an important propulsion system used to power vehicles on land, sea, and in the air. As the power plant for many high performance helicopters, the characteristics of the engine and control are critical to proper vehicle operation as well as being the main determinant to overall vehicle performance. When applied to vertical flight, important distinctions exist in the turbo-shaft engine control system due to the high degree of dynamic coupling between the engine and airframe and the affect on vehicle handling characteristics. In this study, the impact of engine control system architecture is explored relative to engine performance, weight, reliability, safety, and overall cost. Comparison of the impact of architecture on these metrics is investigated as the control system is modified from a legacy centralized structure to a more distributed configuration. A composite strawman system which is typical of turbo-shaft engines in the 1000 to 2000 hp class is described and used for comparison. The overall benefits of these changes to control system architecture are assessed. The availability of supporting technologies to achieve this evolution is also discussed.
A thermoacoustic Stirling heat engine

NASA Astrophysics Data System (ADS)

Backhaus, S.; Swift, G. W.

1999-05-01

Electrical and mechanical power, together with other forms of useful work, are generated worldwide at a rate of about 1012 watts, mostly using heat engines. The efficiency of such engines is limited by the laws of thermodynamics and by practical considerations such as the cost of building and operating them. Engines with high efficiency help to conserve fossil fuels and other natural resources, reducing global-warming emissions and pollutants. In practice, the highest efficiencies are obtained only in the most expensive, sophisticated engines, such as the turbines in central utility electrical plants. Here we demonstrate an inexpensive thermoacoustic engine that employs the inherently efficient Stirling cycle. The design is based on a simple acoustic apparatus with no moving parts. Our first small laboratory prototype, constructed using inexpensive hardware (steel pipes), achieves an efficiency of 0.30, which exceeds the values of 0.10-0.25 attained in other heat engines, with no moving parts. Moreover, the efficiency of our prototype is comparable to that of the common internal combustion engine (0.25-0.40) and piston-driven Stirling engines, (0.20-0.38).
Active Learning in Engineering Education: a (re)introduction

NASA Astrophysics Data System (ADS)

Lima, Rui M.; Andersson, Pernille Hammar; Saalman, Elisabeth

2017-01-01

The informal network 'Active Learning in Engineering Education' (ALE) has been promoting Active Learning since 2001. ALE creates opportunity for practitioners and researchers of engineering education to collaboratively learn how to foster learning of engineering students. The activities in ALE are centred on the vision that learners construct their knowledge based on meaningful activities and knowledge. In 2014, the steering committee of the ALE network reinforced the need to discuss the meaning of Active Learning and that was the base for this proposal for a special issue. More than 40 submissions were reviewed by the European Journal of Engineering Education community and this theme issue ended up with eight contributions, which are different both in their research and Active Learning approaches. These different Active Learning approaches are aligned with the different approaches that can be increasingly found in indexed journals.
Radio imaging of the very-high-energy gamma-ray emission region in the central engine of a radio galaxy.

PubMed

Acciari, V A; Aliu, E; Arlen, T; Bautista, M; Beilicke, M; Benbow, W; Bradbury, S M; Buckley, J H; Bugaev, V; Butt, Y; Byrum, K; Cannon, A; Celik, O; Cesarini, A; Chow, Y C; Ciupik, L; Cogan, P; Cui, W; Dickherber, R; Fegan, S J; Finley, J P; Fortin, P; Fortson, L; Furniss, A; Gall, D; Gillanders, G H; Grube, J; Guenette, R; Gyuk, G; Hanna, D; Holder, J; Horan, D; Hui, C M; Humensky, T B; Imran, A; Kaaret, P; Karlsson, N; Kieda, D; Kildea, J; Konopelko, A; Krawczynski, H; Krennrich, F; Lang, M J; LeBohec, S; Maier, G; McCann, A; McCutcheon, M; Millis, J; Moriarty, P; Ong, R A; Otte, A N; Pandel, D; Perkins, J S; Petry, D; Pohl, M; Quinn, J; Ragan, K; Reyes, L C; Reynolds, P T; Roache, E; Roache, E; Rose, H J; Schroedter, M; Sembroski, G H; Smith, A W; Swordy, S P; Theiling, M; Toner, J A; Varlotta, A; Vincent, S; Wakely, S P; Ward, J E; Weekes, T C; Weinstein, A; Williams, D A; Wissel, S; Wood, M; Walker, R C; Davies, F; Hardee, P E; Junor, W; Ly, C; Aharonian, F; Akhperjanian, A G; Anton, G; Barres de Almeida, U; Bazer-Bachi, A R; Becherini, Y; Behera, B; Bernlöhr, K; Bochow, A; Boisson, C; Bolmont, J; Borrel, V; Brucker, J; Brun, F; Brun, P; Bühler, R; Bulik, T; Büsching, I; Boutelier, T; Chadwick, P M; Charbonnier, A; Chaves, R C G; Cheesebrough, A; Chounet, L-M; Clapson, A C; Coignet, G; Dalton, M; Daniel, M K; Davids, I D; Degrange, B; Deil, C; Dickinson, H J; Djannati-Ataï, A; Domainko, W; Drury, L O'C; Dubois, F; Dubus, G; Dyks, J; Dyrda, M; Egberts, K; Emmanoulopoulos, D; Espigat, P; Farnier, C; Feinstein, F; Fiasson, A; Förster, A; Fontaine, G; Füssling, M; Gabici, S; Gallant, Y A; Gérard, L; Gerbig, D; Giebels, B; Glicenstein, J F; Glück, B; Goret, P; Göhring, D; Hauser, D; Hauser, M; Heinz, S; Heinzelmann, G; Henri, G; Hermann, G; Hinton, J A; Hoffmann, A; Hofmann, W; Holleran, M; Hoppe, S; Horns, D; Jacholkowska, A; de Jager, O C; Jahn, C; Jung, I; Katarzyński, K; Katz, U; Kaufmann, S; Kendziorra, E; Kerschhaggl, M; Khangulyan, D; Khélifi, B; Keogh, D; Kluźniak, W; Kneiske, T; Komin, Nu; Kosack, K; Lamanna, G; Lenain, J-P; Lohse, T; Marandon, V; Martin, J M; Martineau-Huynh, O; Marcowith, A; Maurin, D; McComb, T J L; Medina, M C; Moderski, R; Moulin, E; Naumann-Godo, M; de Naurois, M; Nedbal, D; Nekrassov, D; Nicholas, B; Niemiec, J; Nolan, S J; Ohm, S; Olive, J-F; de Oña Wilhelmi, E; Orford, K J; Ostrowski, M; Panter, M; Paz Arribas, M; Pedaletti, G; Pelletier, G; Petrucci, P-O; Pita, S; Pühlhofer, G; Punch, M; Quirrenbach, A; Raubenheimer, B C; Raue, M; Rayner, S M; Renaud, M; Rieger, F; Ripken, J; Rob, L; Rosier-Lees, S; Rowell, G; Rudak, B; Rulten, C B; Ruppel, J; Sahakian, V; Santangelo, A; Schlickeiser, R; Schöck, F M; Schröder, R; Schwanke, U; Schwarzburg, S; Schwemmer, S; Shalchi, A; Sikora, M; Skilton, J L; Sol, H; Spangler, D; Stawarz, Ł; Steenkamp, R; Stegmann, C; Stinzing, F; Superina, G; Szostek, A; Tam, P H; Tavernet, J-P; Terrier, R; Tibolla, O; Tluczykont, M; van Eldik, C; Vasileiadis, G; Venter, C; Venter, L; Vialle, J P; Vincent, P; Vivier, M; Völk, H J; Volpe, F; Wagner, S J; Ward, M; Zdziarski, A A; Zech, A; Anderhub, H; Antonelli, L A; Antoranz, P; Backes, M; Baixeras, C; Balestra, S; Barrio, J A; Bastieri, D; Becerra González, J; Becker, J K; Bednarek, W; Berger, K; Bernardini, E; Biland, A; Bock, R K; Bonnoli, G; Bordas, P; Borla Tridon, D; Bosch-Ramon, V; Bose, D; Braun, I; Bretz, T; Britvitch, I; Camara, M; Carmona, E; Commichau, S; Contreras, J L; Cortina, J; Costado, M T; Covino, S; Curtef, V; Dazzi, F; De Angelis, A; De Cea del Pozo, E; Delgado Mendez, C; De los Reyes, R; De Lotto, B; De Maria, M; De Sabata, F; Dominguez, A; Dorner, D; Doro, M; Elsaesser, D; Errando, M; Ferenc, D; Fernández, E; Firpo, R; Fonseca, M V; Font, L; Galante, N; García López, R J; Garczarczyk, M; Gaug, M; Goebel, F; Hadasch, D; Hayashida, M; Herrero, A; Hildebrand, D; Höhne-Mönch, D; Hose, J; Hsu, C C; Jogler, T; Kranich, D; La Barbera, A; Laille, A; Leonardo, E; Lindfors, E; Lombardi, S; Longo, F; López, M; Lorenz, E; Majumdar, P; Maneva, G; Mankuzhiyil, N; Mannheim, K; Maraschi, L; Mariotti, M; Martínez, M; Mazin, D; Meucci, M; Miranda, J M; Mirzoyan, R; Miyamoto, H; Moldón, J; Moles, M; Moralejo, A; Nieto, D; Nilsson, K; Ninkovic, J; Oya, I; Paoletti, R; Paredes, J M; Pasanen, M; Pascoli, D; Pauss, F; Pegna, R G; Perez-Torres, M A; Persic, M; Peruzzo, L; Prada, F; Prandini, E; Puchades, N; Reichardt, I; Rhode, W; Ribó, M; Rico, J; Rissi, M; Robert, A; Rügamer, S; Saggion, A; Saito, T Y; Salvati, M; Sanchez-Conde, M; Satalecka, K; Scalzotto, V; Scapin, V; Schweizer, T; Shayduk, M; Shore, S N; Sidro, N; Sierpowska-Bartosik, A; Sillanpää, A; Sitarek, J; Sobczynska, D; Spanier, F; Stamerra, A; Stark, L S; Takalo, L; Tavecchio, F; Temnikov, P; Tescaro, D; Teshima, M; Torres, D F; Turini, N; Vankov, H; Wagner, R M; Zabalza, V; Zandanel, F; Zanin, R; Zapatero, J

2009-07-24

The accretion of matter onto a massive black hole is believed to feed the relativistic plasma jets found in many active galactic nuclei (AGN). Although some AGN accelerate particles to energies exceeding 10(12) electron volts and are bright sources of very-high-energy (VHE) gamma-ray emission, it is not yet known where the VHE emission originates. Here we report on radio and VHE observations of the radio galaxy Messier 87, revealing a period of extremely strong VHE gamma-ray flares accompanied by a strong increase of the radio flux from its nucleus. These results imply that charged particles are accelerated to very high energies in the immediate vicinity of the black hole.
Astrophysical ZeV acceleration in the relativistic jet from an accreting supermassive blackhole

NASA Astrophysics Data System (ADS)

Ebisuzaki, Toshikazu; Tajima, Toshiki

2014-04-01

An accreting supermassive blackhole, the central engine of active galactic nucleus (AGN), is capable of exciting extreme amplitude Alfven waves whose wavelength (wave packet) size is characterized by its clumpiness. The pondermotive force and wakefield are driven by these Alfven waves propagating in the AGN (blazar) jet, and accelerate protons/nuclei to extreme energies beyond Zetta-electron volt (ZeV=1021 eV). Such acceleration is prompt, localized, and does not suffer from the multiple scattering/bending enveloped in the Fermi acceleration that causes excessive synchrotron radiation loss beyond 1019 eV. The production rate of ZeV cosmic rays is found to be consistent with the observed gamma-ray luminosity function of blazars and their time variabilities.
Geotechnical engineering in US elementary schools

NASA Astrophysics Data System (ADS)

Suescun-Florez, Eduardo; Iskander, Magued; Kapila, Vikram; Cain, Ryan

2013-06-01

This paper reports on the results of several geotechnical engineering-related science activities conducted with elementary-school students. Activities presented include soil permeability, contact stress, soil stratigraphy, shallow and deep foundations, and erosion in rivers. The permeability activity employed the LEGO NXT platform for data acquisition, the soil profile and foundations activity employed natural and transparent soils as well as LEGO-based foundation models, and the erosion activity utilised a 3D printer to assist with construction of building models. The activities seek to enhance students' academic achievement, excite them about geotechnical engineering, and motivate them to study science and math. Pre- and post-activity evaluations were conducted to assess both the suitability of the activities and the students' learning. Initial results show that students gain a reasonable understanding of engineering principles. Moreover, the geotechnical engineering activities provided students an opportunity to apply their math skills and science knowledge.
Analyzing the Function of Cartilage Replacements: A Laboratory Activity to Teach High School Students Chemical and Tissue Engineering Concepts

ERIC Educational Resources Information Center

Renner, Julie N.; Emady, Heather N.; Galas, Richards J., Jr.; Zhange, Rong; Baertsch, Chelsey D.; Liu, Julie C.

2013-01-01

A cartilage tissue engineering laboratory activity was developed as part of the Exciting Discoveries for Girls in Engineering (EDGE) Summer Camp sponsored by the Women In Engineering Program (WIEP) at Purdue University. Our goal was to increase awareness of chemical engineering and tissue engineering in female high school students through a…
Crack in the Pipeline: Why Female Underrepresented Racial Minority College Students Leave Engineering

NASA Astrophysics Data System (ADS)

Vazquez-Akim, Jenny Amanda

Female and underrepresented racial minority (URM) students are indicating their interest in STEM fields at increasing rates, yet when examining the engineering discipline specifically disparities in degree completion rates between female URM students and others in the racial or gender majority are even more severe. This study explored female URM college student perceptions of school and classroom climate and the impact these factors had on their decision to persist or to leave engineering. Through a qualitative interview methodology grounded in Social Cognitive Career Theory (SCCT), this study explored factors including self-efficacy, perceived barriers and supports, other-group orientation and outcome expectations that influenced students' academic decision-making. Interview participants consisted of 5 female URM students that matriculated into an engineering major at a top tier, private university but subsequently left the discipline in pursuit of another field of study. The perceptions of this target population were juxtaposed with interview data from 4 male non-URM, 4 female non-URM, and 4 male URM leavers in addition to 7 female URM engineering persisters. As a final component in the research design, 9 undergraduate engineering faculty were interviewed to understand their perceptions of why female URM students leave engineering in pursuit of other disciplines. With faculty being a central component of the academic environment, their perceptions of female URM students, as well as how they view their role in these students' retention, provided insight on this other side of retention question. Salient findings emerged that differentiated female URM leavers' experiences in engineering from other student populations. Female URM leavers were less likely to call upon self-directed learning strategies in response to academic challenges. Perceived academic barriers such as heavy course loads, lack of connection between material and application, and perceived academic deficits deterred these students from persisting in the field. A perceived lack of academic preparation also inhibited female URM students from participating actively in class. Additionally, while targeted support programs were effective in connecting female URM students with their peers and such programs contributed to an overall sense of diversity at the school, a lack of diversity was felt when inside the classroom.
Women Technical Graduates in Hungary.

ERIC Educational Resources Information Center

Turi, Zsuzsa Frank

1980-01-01

Reports on the evolution, since 1945, of the woman's role in science and technology in the Central European nation of Hungary. The report is presented by nine women who are scientists and engineers. (SA)
77 FR 14586 - Supplemental Environmental Impact Statement; Kittitas County, WA

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-12

... Engineer, South Central Region, Federal Highway Administration, 711 South Capital Way, Suite 501, Olympia... SEIS is limited to the social, economic, and environmental effects of constructing and operating a...
Thermal barrier coatings application in diesel engines

NASA Technical Reports Server (NTRS)

Fairbanks, J. W.

1995-01-01

Commercial use of thermal barrier coatings in diesel engines began in the mid 70's by Dr,. Ingard Kvernes at the Central Institute for Industrial Research in Oslo, Norway. Dr. Kvernes attributed attack on diesel engine valves and piston crowns encountered in marine diesel engines in Norwegian ships as hot-corrosion attributed to a reduced quality of residual fuel. His solution was to coat these components to reduce metal temperature below the threshold of aggressive hot-corrosion and also to provide protection. The Department of Energy has supported thermal barrier coating development for diesel engine applications. In the Clean Diesel - 50 Percent Efficient (CD-50) engine for the year 2000, thermal barrier coatings will be used on piston crowns and possibly other components. The primary purpose of the thermal barrier coatings will be to reduce thermal fatigue as the engine peak cylinder pressure will nearly be doubled. As the coatings result in higher available energy in the exhaust gas, efficiency gains are achieved through use of this energy by turbochargers, turbocompounding or thermoelectric generators.
Liquid Rocket Booster Study. Volume 2, Book 1

NASA Technical Reports Server (NTRS)

1989-01-01

The recommended Liquid Rocket Booster (LRB) concept is shown which uses a common main engine with the Advanced Launch System (ALS) which burns LO2 and LH2. The central rationale is based on the belief that the U.S. can only afford one big new rocket engine development in the 1990's. A LO2/LH2 engine in the half million pound thrust class could satisfy STS LRB, ALS, and Shuttle C (instead of SSMEs). Development costs and higher production rates can be shared by NASA and USAF. If the ALS program does not occur, the LO2/RP-1 propellants would produce slight lower costs for and STS LRB. When the planned Booster Engine portion of the Civil Space Transportation Initiatives has provided data on large pressure fed LO2/RP-1 engines, then the choice should be reevaluated.
Security Requirements Management in Software Product Line Engineering

NASA Astrophysics Data System (ADS)

Mellado, Daniel; Fernández-Medina, Eduardo; Piattini, Mario

Security requirements engineering is both a central task and a critical success factor in product line development due to the complexity and extensive nature of product lines. However, most of the current product line practices in requirements engineering do not adequately address security requirements engineering. Therefore, in this chapter we will propose a security requirements engineering process (SREPPLine) driven by security standards and based on a security requirements decision model along with a security variability model to manage the variability of the artefacts related to security requirements. The aim of this approach is to deal with security requirements from the early stages of the product line development in a systematic way, in order to facilitate conformance with the most relevant security standards with regard to the management of security requirements, such as ISO/IEC 27001 and ISO/IEC 15408.
United States Department of Energy solar receiver technology development

NASA Astrophysics Data System (ADS)

Klimas, P. C.; Diver, R. B.; Chavez, J. M.

The United States Department of Energy (DOE), through Sandia National Laboratories, has been conducting a Solar Thermal Receiver Technology Development Program, which maintains a balance between analytical modeling, bench and small scale testing, and experimentation conducted at scales representative of commercially-sized equipment. Central receiver activities emphasize molten salt-based systems on large scales and volumetric devices in the modeling and small scale testing. These receivers are expected to be utilized in solar power plants rated between 100 and 200 MW. Distributed receiver research focuses on liquid metal refluxing devices. These are intended to mate parabolic dish concentrators with Stirling cycle engines in the 5 to 25 kW(sub e) power range. The effort in the area of volumetric receivers is less intensive and highly cooperative in nature. A ceramic foam absorber of Sandia design was successfully tested on the 200 kW(sub t) test bed at Plataforma Solar during 1989. Material integrity during the approximately 90-test series was excellent. Significant progress has been made with parabolic dish concentrator-mounted receivers using liquid metals (sodium or a potassium/sodium mixture) as heat transport media. Sandia has successfully solar-tested a pool boiling reflux receiver sized to power a 25 kW Stirling engine. Boiling stability and transient operation were both excellent. This document describes these activities in detail and will outline plans for future development.
Enhancement of tissue engineered bone formation by a low pressure system improving cell seeding and medium perfusion into a porous scaffold.

PubMed

Wang, Juyong; Asou, Yoshinori; Sekiya, Ichiro; Sotome, Shinichi; Orii, Hisaya; Shinomiya, Kenichi

2006-05-01

To obtain more extensive bone formation in composites of porous ceramics and bone marrow stromal cells (BMSCs), we hypothesized that a low-pressure system would serve to facilitate the perfusion of larger number of BMSCs into the porous scaffold, enhancing bone formation within the composites. After culturing BMSCs in osteogenic medium, porous blocks of beta-tricalcium phosphate (beta-TCP) were soaked in the cell suspension. Composites of the block and BMSCs were put immediately into a vacuum desiccator. Low pressure was applied to the low pressure group, while controls were left at atmospheric pressure. Composites were incubated in vitro or subcutaneously implanted into syngeneic rats, then analyzed biologically and histologically. In the in vitro group, cell suspension volume, cell seeding efficiency, alkaline phosphatase (ALP) activity, and DNA content in the beta-TCP blocks were significantly higher in low pressure group than in the controls. Scanning electron microscopy (SEM) demonstrated that a greater number of cells covered the central parts of the composites in the low pressure group. ALP activity in the composites was increased at 3 and 6 weeks after implantation into rats. Histomorphometric analysis revealed more uniform and extensive bone formation in the low pressure group than in the controls. The application of low pressure during the seeding of BMSCs in perfusing medium into a porous scaffold is useful for tissue-engineered bone formation.
Mega-Project Construction Management: The Corps of Engineers and Bechtel Group in Saudi Arabia

DTIC Science & Technology

1991-02-01

collaborative efforts of government and private firms; utilizing state-of-the-art technology; and, having economic , sociocultural, and environmental impacts...pushing out their traditional managerial corps of stodgy engineers and aristocrats."LA Although I don’t focus on individual personalities in this...help from Western economists the Central Planning Organization created Saudi Arabia’s first five year economic plan, which covered the years 1970 to
Wildlife Habitat Impact Assessment, Chief Joseph Dam Project, Washington : Project Report 1992.

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

Kuehn, Douglas; Berger, Matthew

1992-01-01

Under the Pacific Northwest Electric Power Planning and Conservation Act of 1980, and the subsequent Northwest Power Planning Council`s Columbia River Basin Fish and Wildlife Program, a wildlife habitat impact assessment and identification of mitigation objectives have been developed for the US Army Corps of Engineer`s Chief Joseph Dam Project in north-central Washington. This study will form the basis for future mitigation planning and implementation.
Emissions performance of abatement technologies over the proposed EEC extra-urban driving cycle

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

VanBeckhoven, L.C.; Rijkeboer, R.C.

1989-01-01

The definition of what is likely to be the new EEC extra-urban cycle has made it possible to determine the emission characteristics of cars fitted with different emissions control equipment. Central to the evaluation program were three versions of experimental lean and dilute burn engines compared with engine modifications and open and closed loop three-way catalyst systems. This paper describes the evaluation program and evaluates its results.
Introducing a new semi-active engine mount using force controlled variable stiffness

NASA Astrophysics Data System (ADS)

Azadi, Mojtaba; Behzadipour, Saeed; Faulkner, Gary

2013-05-01

This work introduces a new concept in designing semi-active engine mounts. Engine mounts are under continuous development to provide better and more cost-effective engine vibration control. Passive engine mounts do not provide satisfactory solution. Available semi-active and active mounts provide better solutions but they are more complex and expensive. The variable stiffness engine mount (VSEM) is a semi-active engine mount with a simple ON-OFF control strategy. However, unlike available semi-active engine mounts that work based on damping change, the VSEM works based on the static stiffness change by using a new fast response force controlled variable spring. The VSEM is an improved version of the vibration mount introduced by the authors in their previous work. The results showed significant performance improvements over a passive rubber mount. The VSEM also provides better vibration control than a hydromount at idle speed. Low hysteresis and the ability to be modelled by a linear model in low-frequency are the advantages of the VSEM over the vibration isolator introduced earlier and available hydromounts. These specifications facilitate the use of VSEM in the automotive industry, however, further evaluation and developments are needed for this purpose.
Development and Evaluation of an Undergraduate Multidisciplinary Project Activity in Engineering and Design

ERIC Educational Resources Information Center

Smith, David R.; Cole, Joanne

2012-01-01

The School of Engineering and Design Multidisciplinary Project (MDP) at Brunel University is a one week long project based activity involving first year undergraduate students from across the School subject areas of Electronic and Computer Engineering, Mechanical Engineering, Civil Engineering and Design. This paper describes the main aims of the…

Advanced Combustion Numerics and Modeling - FY18 First Quarter Report

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

Whitesides, R. A.; Killingsworth, N. J.; McNenly, M. J.

This project is focused on early stage research and development of numerical methods and models to improve advanced engine combustion concepts and systems. The current focus is on development of new mathematics and algorithms to reduce the time to solution for advanced combustion engine design using detailed fuel chemistry. The research is prioritized towards the most time-consuming workflow bottlenecks (computer and human) and accuracy gaps that slow ACS program members. Zero-RK, the fast and accurate chemical kinetics solver software developed in this project, is central to the research efforts and continues to be developed to address the current and emergingmore » needs of the engine designers, engine modelers and fuel mechanism developers.« less
An engineering design approach to systems biology.

PubMed

Janes, Kevin A; Chandran, Preethi L; Ford, Roseanne M; Lazzara, Matthew J; Papin, Jason A; Peirce, Shayn M; Saucerman, Jeffrey J; Lauffenburger, Douglas A

2017-07-17

Measuring and modeling the integrated behavior of biomolecular-cellular networks is central to systems biology. Over several decades, systems biology has been shaped by quantitative biologists, physicists, mathematicians, and engineers in different ways. However, the basic and applied versions of systems biology are not typically distinguished, which blurs the separate aspirations of the field and its potential for real-world impact. Here, we articulate an engineering approach to systems biology, which applies educational philosophy, engineering design, and predictive models to solve contemporary problems in an age of biomedical Big Data. A concerted effort to train systems bioengineers will provide a versatile workforce capable of tackling the diverse challenges faced by the biotechnological and pharmaceutical sectors in a modern, information-dense economy.
A Multi-wavelength Study of the Turbulent Central Engine of the Low-mass AGN Hosted by NGC 404

NASA Astrophysics Data System (ADS)

Nyland, Kristina; Davis, Timothy A.; Nguyen, Dieu D.; Seth, Anil; Wrobel, Joan M.; Kamble, Atish; Lacy, Mark; Alatalo, Katherine; Karovska, Margarita; Maksym, W. Peter; Mukherjee, Dipanjan; Young, Lisa M.

2017-08-01

The nearby dwarf galaxy NGC 404 harbors a low-luminosity active galactic nucleus powered by the lowest-mass (<150,000 M ⊙) central massive black hole (MBH), with a dynamical mass constraint, currently known, thus providing a rare low-redshift analog to the MBH “seeds” that formed in the early universe. Here, we present new imaging of the nucleus of NGC 404 at 12-18 GHz with the Karl G. Jansky Very Large Array (VLA) and observations of the CO(2-1) line with the Atacama Large Millimeter/Submillimeter Array (ALMA). For the first time, we have successfully resolved the nuclear radio emission, revealing a centrally peaked, extended source spanning 17 pc. Combined with previous VLA observations, our new data place a tight constraint on the radio spectral index and indicate an optically thin synchrotron origin for the emission. The peak of the resolved radio source coincides with the dynamical center of NGC 404, the center of a rotating disk of molecular gas, and the position of a compact, hard X-ray source. We also present evidence for shocks in the NGC 404 nucleus from archival narrowband HST imaging, Chandra X-ray data, and Spitzer mid-infrared spectroscopy, and discuss possible origins for the shock excitation. Given the morphology, location, and steep spectral index of the resolved radio source, as well as constraints on nuclear star formation from the ALMA CO(2-1) data, we find the most likely scenario for the origin of the radio source in the center of NGC 404 to be a radio outflow associated with a confined jet driven by the active nucleus.
A Multi-wavelength Study of the Turbulent Central Engine of the Low-mass AGN Hosted by NGC 404

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

Nyland, Kristina; Lacy, Mark; Davis, Timothy A.

The nearby dwarf galaxy NGC 404 harbors a low-luminosity active galactic nucleus powered by the lowest-mass (<150,000 M {sub ⊙}) central massive black hole (MBH), with a dynamical mass constraint, currently known, thus providing a rare low-redshift analog to the MBH “seeds” that formed in the early universe. Here, we present new imaging of the nucleus of NGC 404 at 12–18 GHz with the Karl G. Jansky Very Large Array (VLA) and observations of the CO(2–1) line with the Atacama Large Millimeter/Submillimeter Array (ALMA). For the first time, we have successfully resolved the nuclear radio emission, revealing a centrally peaked,more » extended source spanning 17 pc. Combined with previous VLA observations, our new data place a tight constraint on the radio spectral index and indicate an optically thin synchrotron origin for the emission. The peak of the resolved radio source coincides with the dynamical center of NGC 404, the center of a rotating disk of molecular gas, and the position of a compact, hard X-ray source. We also present evidence for shocks in the NGC 404 nucleus from archival narrowband HST imaging, Chandra X-ray data, and Spitzer mid-infrared spectroscopy, and discuss possible origins for the shock excitation. Given the morphology, location, and steep spectral index of the resolved radio source, as well as constraints on nuclear star formation from the ALMA CO(2–1) data, we find the most likely scenario for the origin of the radio source in the center of NGC 404 to be a radio outflow associated with a confined jet driven by the active nucleus.« less
Toward Understanding the Fanaroff-Riley Dichotomy in Radio Source Morphology and Power

NASA Astrophysics Data System (ADS)

Baum, Stefi A.; Zirbel, Esther L.; O'Dea, Christopher P.

1995-09-01

In Paper I we presented the results of a study of the interrelationships between host galaxy magnitude, optical line luminosity, and radio luminosity in a large sample of Fanaroff-Riley classes 1 and 2 (FR 1 and FR 2) radio galaxies. We report several important differences between the FR 1 and FR 2 radio galaxies. At the same host galaxy magnitude or radio luminosity, the FR 2's produce substantially more optical line emission (by roughly an order of magnitude or more) than do FR 1's. Similarly, FR 2 sources produce orders of magnitude more line luminosity than do radio-quiet galaxies of the same optical magnitude, while FR 1 sources and radio-quiet galaxies of the same optical magnitude produce similar line luminosities. Combining these results with previous results from the literature, we conclude that while the emission-line gas in the FR 2's is indeed photoionized by a nuclear UV continuum source from the AGN, the emission-line gas in the FR 1's may be energized predominantly by processes associated with the host galaxy itself. The apparent lack of a strong UV continuum source from the central engine in FR 1 sources can be understood in two different ways. In the first scenario, FR l's are much more efficient at covering jet bulk kinetic energy into radio luminosity than FR 2's, such that an FR 1 has a much lower bolometric AGN luminosity (hence nuclear UV continuum source) than does an FR 2 of the same radio luminosity. We discuss the pros and cons of this model and conclude that the efficiency differences needed between FR 2 and FR 1 radio galaxies are quite large and may lead to difficulties with the interpretation since it would suggest that FR 2 radio source deposit very large amounts of kinetic energy into the ISM Intracluster Medium. However, this interpretation remains viable. Alternatively, it may be that the AGNs in FR 1 sources simply produce far less radiant UV energy than do those in FR 2 sources. That is, FR 1 sources may funnel a higher fraction of the total energy output from the AGNs into jet kinetic energy versus radiant energy than do FR 2 sources. If this interpretation is correct, then this suggests that there is a fundamental difference in the central engine and/or in the immediate "accretion region" around the engine in FR 1 and FR 2 radio galaxies. We note also the absence of FR 1 sources with nuclear broad line regions and suggest that the absence of the BLR is tied to the absence of the "isotropic" nuclear UV continuum source in FR 1 sources. We put forth the possibility that the FR 1/FR 2 dichotomy (i.e., the observed differences in the properties of low- and high-power radio sources) is due to qualitative differences in the structural properties of the central engines in these two types of sources. Following early work by Rees et al. (1982), we suggest the possibility that FR 1 sources are produced when the central engine is fed at a lower accretion rate, leading to the creation of a source in which the ratio of radiant to jet bulk kinetic energy is low, while FR 2 sources are produced when the central engine is fed at a higher accretion rate, causing the central engine to deposit a higher fraction of its energy in radiant energy. We further suggest the possibility that associated differences in the spin properties of the central black hole between FR 1 (lower spin) and FR 2 (higher spin) sources may be responsible for the different collimation properties and Mach numbers of the jets produced by these two types of radio-loud galaxies. This scenario, although currently clearly speculative, is nicely consistent with our current picture of the triggering, feeding, environments, and evolution of powerful radio galaxies. This model allows for evolution of these properties with time for example, the mass accretion rate and BH spin may decline with time causing an FR 2 radio source or quasar to evolve into a FR 1 radio source.
49 CFR 229.5 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

... locomotive engineer attentiveness by monitoring select locomotive engineer-induced control activities. If fluctuation of a monitored locomotive engineer-induced control activity is not detected within a predetermined... monitored control, or acknowledge the alerter alarm activity through a manual reset provision, results in a...
49 CFR 229.5 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... locomotive engineer attentiveness by monitoring select locomotive engineer-induced control activities. If fluctuation of a monitored locomotive engineer-induced control activity is not detected within a predetermined... monitored control, or acknowledge the alerter alarm activity through a manual reset provision, results in a...
49 CFR 229.5 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... locomotive engineer attentiveness by monitoring select locomotive engineer-induced control activities. If fluctuation of a monitored locomotive engineer-induced control activity is not detected within a predetermined... monitored control, or acknowledge the alerter alarm activity through a manual reset provision, results in a...
Curricular Reform: Systems Modeling and Sustainability in Civil and Environmental Engineering at the University of Vermont

NASA Astrophysics Data System (ADS)

Rizzo, D. M.; Hayden, N. J.; Dewoolkar, M.; Neumann, M.; Lathem, S.

2009-12-01

Researchers at the University of Vermont were awarded a NSF-sponsored Department Level Reform (DLR) grant to incorporate a systems approach to engineering problem solving within the civil and environmental engineering programs. A systems approach challenges students to consider the environmental, social, and economic aspects within engineering solutions. Likewise, sustainability requires a holistic approach to problem solving that includes economic, social and environmental factors. Our reform has taken a multi-pronged approach in two main areas that include implementing: a) a sequence of three systems courses related to environmental and transportation systems that introduce systems thinking, sustainability, and systems analysis and modeling; and b) service-learning (SL) projects as a means of practicing the systems approach. Our SL projects are good examples of inquiry-based learning that allow students to emphasize research and learning in areas of most interest to them. The SL projects address real-world open-ended problems. Activities that enhance IT and soft skills for students are incorporated throughout the curricula. Likewise, sustainability has been a central piece of the reform. We present examples of sustainability in the SL and modeling projects within the systems courses (e.g., students have used STELLA™ systems modeling software to address the impact of different carbon sequestration strategies on global climate change). Sustainability in SL projects include mentoring home schooled children in biomimicry projects, developing ECHO exhibits and the design of green roofs, bioretention ponds and porous pavement solutions. Assessment includes formative and summative methods involving student surveys and focus groups, faculty interviews and observations, and evaluation of student work.
GRB 120422A: a Low-Luminosity Gamma-Ray Burst Driven by a Central Engine

NASA Technical Reports Server (NTRS)

Zhang, Bin-Bin; Fan, Yi-Zhong; Shen, Rong-Feng; Xu, Dong; Zhang, Fu-Wen; Wei, Da-Ming; Burrows, David N.; Zhang, Bing; Gehrels, Neil

2012-01-01

GRB 120422A is a low-luminosity gamma-ray burst (GRB) associated with a bright supernova, which distinguishesitself by its relatively short T(sub 90) (approximately 5 s) and an energetic and steep-decaying X-ray tail. We analyze the Swift BurstAlert Telescope and X-ray Telescope data and discuss the physical implications. We show that the steep declineearly in the X-ray light curve can be interpreted as the curvature tail of a late emission episode around 58-86 s,with a curved instantaneous spectrum at the end of the emission episode. Together with the main activity in thefirst 20 s and the weak emission from 40 s to 60 s, the prompt emission is variable, which points to a centralengine origin in contrast to a shock-breakout origin, which is used to interpret some other nearby low-luminosity supernova GRBs. Both the curvature effect model and interpreting the early shallow decay as the coasting externalforward shock emission in a wind medium provide a constraint on the bulk Lorentz factor to be around several.Comparing the properties ofGRB 120422A and other supernova GRBs,we find that themain criterion to distinguish engine-driven GRBs from shock-breakout GRBs is the time-averaged -ray luminosity. Engine-driven GRBs likelyhave a luminosity above approximately 10(sup 48) erg s(sup -1).
Stable Ectopic Expression of ST6GALNAC5 Induces Autocrine MET Activation and Anchorage-Independence in MDCK Cells.

PubMed

Chu, Chia; Bottaro, Donald P; Betenbaugh, Michael J; Shiloach, Joseph

2016-01-01

The epithelial-mesenchymal transition (EMT) is a complex cancer progression that can boost the metastatic potential of transformed cells by inducing migration, loss of cell adhesion, and promoting proliferation under anchorage-independent conditions. A DNA microarray analysis was performed comparing parental anchorage-dependent MDCK cells and anchorage-independent MDCK cells that were engineered to express human siat7e (ST6GALNAC5). The comparison identified several genes involved in the EMT process that were differentially expressed between the anchorage-dependent and the anchorage-independent MDCK cell lines. The hepatocyte growth factor gene (hgf) was found to be over-expressed in the engineered MDCK-siat7e cells at both transcription and protein expression levels. Phosphorylation analysis of the MET receptor tyrosine kinase confirmed the activation of an autocrine loop of the HGF/ MET signaling pathway in the MDCK-siat7e cells. When MET activities were suppressed by using the small-molecular inhibitor drug PF-02341066 (Crizotinib), the anchorage-independent MDCK-siat7e cells reverted to the cellular morphology of the parental anchorage-dependent MDCK cells. These observations indicate that the MET receptor plays a central role in the growth properties of the MDCK cells and its phosphorylation status is likely dependent on sialylation. Further investigation of the downstream signaling targets in the MET network showed that the degree of MDCK cell adhesion correlated with secretion levels of a matrix metalloproteinase, MMP1, suggesting a role of metalloproteinases in the EMT process. These results demonstrate that in addition to its application in biotechnology processes, MDCK-siat7e may serve as a model cell for metastasis studies to decipher the sequence of events leading up to the activation of EMT.
Immunotherapy for the treatment of drug abuse.

PubMed

Kosten, Thomas; Owens, S Michael

2005-10-01

Antibody therapy (as either active or passive immunization) is designed primarily to prevent drugs of abuse from entering the central nervous system (CNS). Antidrug antibodies reduce rush, euphoria, and drug distribution to the brain at doses that exceed the apparent binding capacity of the antibody. This is accomplished through a pharmacokinetic antagonism, which reduces the amount of drug in the brain, the rate of clearance across the blood-brain barrier, and the volume of drug distribution. Because the antibodies remain primarily in the circulatory system, they have no apparent central nervous system side effects. Active immunization with drug-protein conjugate vaccines has been tested for cocaine, heroin, methamphetamine, and nicotine in animal, with 1 cocaine and 3 nicotine vaccines in Phase 2 human trials. Passive immunization with high affinity monoclonal antibodies has been tested for cocaine, methamphetamine, nicotine, and phencyclidine (PCP) in preclinical animal models. Antibodies have 2 immediate clinical applications in drug abuse treatment: to treat drug overdose and to reduce relapse to drug use in addicted patients. The specificity of the therapies, the lack of addiction liability, minimal side effects, and long-lasting protection against drug use offer major therapeutic benefit over conventional small molecule agonists and antagonists. Immunotherapies can also be combined with other antiaddiction medications and enhance behavioral therapies. Current immunotherapies already show efficacy, but improved antigen design and antibody engineering promise highly specific and rapidly developed treatments for both existing and future addictions.
Re-Educating Jet-Engine-Researchers to Stay Relevant

NASA Astrophysics Data System (ADS)

Gal-Or, Benjamin

2016-06-01

To stay relevantly supported, jet-engine researchers, designers and operators should follow changing uses of small and large jet engines, especially those anticipated to be used by/in the next generation, JET-ENGINE-STEERED ("JES") fleets of jet drones but fewer, JES-Stealth-Fighter/Strike Aircraft. In addition, some diminishing returns from isolated, non-integrating, jet-engine component studies, vs. relevant, supersonic, shock waves control in fluidic-JES-side-effects on compressor stall dynamics within Integrated Propulsion Flight Control ("IPFC"), and/or mechanical JES, constitute key relevant methods that currently move to China, India, South Korea and Japan. The central roles of the jet engine as primary or backup flight controller also constitute key relevant issues, especially under post stall conditions involving induced engine-stress while participating in crash prevention or minimal path-time maneuvers to target. And when proper instructors are absent, self-study of the JES-STVS REVOLUTION is an updating must, where STVS stands for wing-engine-airframe-integrated, embedded stealthy-jet-engine-inlets, restructured engines inside Stealth, Tailless, canard-less, Thrust Vectoring IFPC Systems. Anti-terror and Airliners Super-Flight-Safety are anticipated to overcome US legislation red-tape that obstructs JES-add-on-emergency-kits-use.
Introduction to the LaRC central scientific computing complex

NASA Technical Reports Server (NTRS)

Shoosmith, John N.

1993-01-01

The computers and associated equipment that make up the Central Scientific Computing Complex of the Langley Research Center are briefly described. The electronic networks that provide access to the various components of the complex and a number of areas that can be used by Langley and contractors staff for special applications (scientific visualization, image processing, software engineering, and grid generation) are also described. Flight simulation facilities that use the central computers are described. Management of the complex, procedures for its use, and available services and resources are discussed. This document is intended for new users of the complex, for current users who wish to keep appraised of changes, and for visitors who need to understand the role of central scientific computers at Langley.
Spectral molecular line surveys of active galaxies

NASA Astrophysics Data System (ADS)

Villicana Pedraza, Ilhuiyolitzin

The enormous mass of molecular gas and dust found in the nuclei of active galaxies has a major role in feeding the activity (either starburst or AGN) and therefore in the galactic evolution. Thus, observations of the molecular can provide clues to identify and analyze the type of activity in very deeply obscured galactic nuclei. Indeed, studies of the chemical composition in starburst galaxies via wide band spectral has shown the potential of molecular spectroscopy to trace the physical and chemical propierties of their central ISM material. In this work we present the analysis of the emission of molecules such as HCN, CCH, CN,CS,HCO+, HNC, CH3OH, among others obtained from the survey of spectra of the 3 near seyfert galaxies observed with the APEX Telescope. We have also found that one of the molecules is not at LTE conditions- H3O+ molecule. Whether radiatively pumped or maser enhanced, the emission of H3O+ is emerging from a different region from most other molecules (distributed in two molecular lobes seen as the two velocity components). H3O+ emission peaks close to the systemic velocity of the system, particularly clear in NGC 253, which suggest the emission to be centrally peaked towards the nuclear engine, It is common in the same kind of galaxies? In adition, preliminar conclusions show isotopic ratio 12C/13C in starburst galaxies is higher than nuclei of the Milky Way indicating that interestelar matter in starburst nuclei is less processed than in the nucleus of the Milky Way .There are two possible explanations for this effect in starburst, nucleosynthesis differences due stellar population history and acretion of matter from halo.
Experimental/Analytical Characterization of the RBCC Rocket-Ejector Mode

NASA Technical Reports Server (NTRS)

Ruf, J. H.; Lehman, M.; Pal, S.; Santoro, R. J.

2000-01-01

The experimental/analytical research work described here addresses the rocket-ejector mode (Mach 0-2 operational range) of the RBCC engine. The experimental phase of the program includes studying the mixing and combustion characteristics of the rocket-ejector system utilizing state-of-the-art diagnostic techniques. A two-dimensional variable geometry rocket-ejector system with enhanced optical access was utilized as the experimental platform. The goals of the experimental phase of the research being conducted at Penn State are to: (a) systematically increase the range of rocket-ejector understanding over a wide range of flow/geometry parameters and (b) provide a comprehensive data base for evaluating and anchoring CFD codes. Concurrent with the experimental activities, a CFD code benchmarking effort at Marshall Space Flight Center is also being used to further investigate the RBCC rocket-ejector mode. Experiments involving the single rocket based optically-accessible rocket-ejector system have been conducted for Diffusion and Afterburning (DAB) as well as Simultaneous Mixing and Combustion configurations. For the DAB configuration, air is introduced (direct-connect) or ejected (sea-level static) into a constant area mixer section with a centrally located gaseous oxygen (GO2)/gaseous hydrogen (GH2) rocket combustor. The downstream flowpath for this configuration includes a diffuser, an afterburner and a final converging nozzle. For the SMC configuration, the rocket is centrally located in a slightly divergent duct. For all tested configurations, global measurements of the axial pressure and heat transfer profiles as well as the overall engine thrust were made. Detailed measurements include major species concentration (H2 O2 N2 and H2O) profiles at various mixer locations made using Raman spectroscopy. Complementary CFD calculations of the flowfield at the experimental conditions also provide additional information on the physics of the problem. These calculations are being conducted at Marshall Space Flight Center to benchmark the FDNS code for RBCC engine operations for such configurations. The primary fluid physics of interests are the mixing and interaction of the rocket plume and secondary flow, subsequent combustion of the fuel rich rocket exhaust with the secondary flow and combustion of the injected afterburner flow. The CFD results are compared to static pressure along the RBCC duct walls, Raman Spectroscopy specie distribution data at several axial locations, net engine thrust and entrained air for the SLS cases. The CFD results compare reasonably well with the experimental results.
Mutagenicity of diesel exhaust particles from an engine with differing exhaust after treatments.

PubMed

Shi, X-C; Keane, M J; Ong, T; Li, S-Q; Bugarski, A B

2010-01-01

This study was conducted to investigate the effects of engine operating conditions and exhaust aftertreatments on the mutagenicity of diesel particulate matter (DPM) collected directly in an underground mine environment. A number of after-treatment devices are currently used on diesel engines in mines, but it is critical to determine whether reductions in DPM concentrations result in a corresponding decrease in adverse health effects. An eddy-current dynamometer was used to operate naturally aspirated mechanically controlled engine at several steady-state conditions. The samples were collected when the engine was equipped with a standard muffler, a diesel oxidation catalytic converter, two types of uncatalyzed diesel particulate filter systems, and three types of disposable diesel particulate filter elements. Bacterial gene mutation activity of DPM was tested on acetone extracts using the Ames Salmonella assay. The results indicated strong correlation between engine operating conditions and mutagenic activity of DPM. When the engine was fitted with muffler, the mutagenic activity was observed for the samples collected from light-load, but not heavy-load operating conditions. When the engine was equipped with a diesel oxidation catalyst, the samples did not exhibit mutagenic activity for any of four engine operating conditions. Mutagenic activity was observed for the samples collected when the engine was retrofitted with three types of disposable filters and sintered metal diesel particulate filter and operated at light load conditions. However, those filtration systems substantially reduced the concentration-normalized mutagenic activity from the levels observed for the muffler.
Interfacing with the nervous system: a review of current bioelectric technologies.

PubMed

Sahyouni, Ronald; Mahmoodi, Amin; Chen, Jefferson W; Chang, David T; Moshtaghi, Omid; Djalilian, Hamid R; Lin, Harrison W

2017-10-23

The aim of this study is to discuss the state of the art with regard to established or promising bioelectric therapies meant to alter or control neurologic function. We present recent reports on bioelectric technologies that interface with the nervous system at three potential sites-(1) the end organ, (2) the peripheral nervous system, and (3) the central nervous system-while exploring practical and clinical considerations. A literature search was executed on PubMed, IEEE, and Web of Science databases. A review of the current literature was conducted to examine functional and histomorphological effects of neuroprosthetic interfaces with a focus on end-organ, peripheral, and central nervous system interfaces. Innovations in bioelectric technologies are providing increasing selectivity in stimulating distinct nerve fiber populations in order to activate discrete muscles. Significant advances in electrode array design focus on increasing selectivity, stability, and functionality of implantable neuroprosthetics. The application of neuroprosthetics to paretic nerves or even directly stimulating or recording from the central nervous system holds great potential in advancing the field of nerve and tissue bioelectric engineering and contributing to clinical care. Although current physiotherapeutic and surgical treatments seek to restore function, structure, or comfort, they bear significant limitations in enabling cosmetic or functional recovery. Instead, the introduction of bioelectric technology may play a role in the restoration of function in patients with neurologic deficits.
Preclinical evidence supporting the clinical development of central pattern generator-modulating therapies for chronic spinal cord-injured patients

PubMed Central

2014-01-01

Ambulation or walking is one of the main gaits of locomotion. In terrestrial animals, it may be defined as a series of rhythmic and bilaterally coordinated movement of the limbs which creates a forward movement of the body. This applies regardless of the number of limbs—from arthropods with six or more limbs to bipedal primates. These fundamental similarities among species may explain why comparable neural systems and cellular properties have been found, thus far, to control in similar ways locomotor rhythm generation in most animal models. The aim of this article is to provide a comprehensive review of the known structural and functional features associated with central nervous system (CNS) networks that are involved in the control of ambulation and other stereotyped motor patterns—specifically Central Pattern Generators (CPGs) that produce basic rhythmic patterned outputs for locomotion, micturition, ejaculation, and defecation. Although there is compelling evidence of their existence in humans, CPGs have been most studied in reduced models including in vitro isolated preparations, genetically-engineered mice and spinal cord-transected animals. Compared with other structures of the CNS, the spinal cord is generally considered as being well-preserved phylogenetically. As such, most animal models of spinal cord-injured (SCI) should be considered as valuable tools for the development of novel pharmacological strategies aimed at modulating spinal activity and restoring corresponding functions in chronic SCI patients. PMID:24910602
DOE Office of Scientific and Technical Information (OSTI.GOV)

Layne Pincock; Wendell Hintze; Dr. Koji Shirai

Following the massive earthquake and resulting tsunami damage in March of 2011 at the Fukushima Daiichi nuclear power plant in Japan, interest was amplified for what was done for recovery at the Three Mile Island Unit 2 (TMI-2) in the United States following its meltdown in 1979. Many parallels could be drawn between to two accidents. This paper presents the results of research done into the TMI-2 recovery effort and its applicability to the Fukushima Daiichi cleanup. This research focused on three topics: packaging, transportation, and disposition. This research work was performed as a collaboration between Japan’s Central Research Institutemore » of Electric Power Industry (CRIEPI) and the Idaho National Laboratory (INL). Hundreds of TMI-2 related documents were searched and pertinent information was gleaned from these documents. Other important information was also obtained by interviewing employees who were involved first hand in various aspects of the TMI-2 cleanup effort. This paper is organized into three main sections: (1) Transport from Three Mile Island to Central Facilities Area at INL, (2) Transport from INL Central Receiving Facility to INL Test Area North (TAN) and wet storage at TAN, and (3) Transport from TAN to INL Idaho Nuclear Technology and Engineering Center (INTEC) and Dry Storage at INTEC. Within each of these sections, lessons learned from performing recovery activities are presented and their applicability to the Fukushima Daiichi nuclear power plant cleanup are outlined.« less

Characterization and engineering of a plastic-degrading aromatic polyesterase

PubMed Central

Austin, Harry P.; Allen, Mark D.; Rorrer, Nicholas A.; Kearns, Fiona L.; Silveira, Rodrigo L.; Pollard, Benjamin C.; Dominick, Graham; El Omari, Kamel; Mykhaylyk, Vitaliy; Michener, William E.; Amore, Antonella; Skaf, Munir S.; Crowley, Michael F.; Thorne, Alan W.; Johnson, Christopher W.; Woodcock, H. Lee

2018-01-01

Poly(ethylene terephthalate) (PET) is one of the most abundantly produced synthetic polymers and is accumulating in the environment at a staggering rate as discarded packaging and textiles. The properties that make PET so useful also endow it with an alarming resistance to biodegradation, likely lasting centuries in the environment. Our collective reliance on PET and other plastics means that this buildup will continue unless solutions are found. Recently, a newly discovered bacterium, Ideonella sakaiensis 201-F6, was shown to exhibit the rare ability to grow on PET as a major carbon and energy source. Central to its PET biodegradation capability is a secreted PETase (PET-digesting enzyme). Here, we present a 0.92 Å resolution X-ray crystal structure of PETase, which reveals features common to both cutinases and lipases. PETase retains the ancestral α/β-hydrolase fold but exhibits a more open active-site cleft than homologous cutinases. By narrowing the binding cleft via mutation of two active-site residues to conserved amino acids in cutinases, we surprisingly observe improved PET degradation, suggesting that PETase is not fully optimized for crystalline PET degradation, despite presumably evolving in a PET-rich environment. Additionally, we show that PETase degrades another semiaromatic polyester, polyethylene-2,5-furandicarboxylate (PEF), which is an emerging, bioderived PET replacement with improved barrier properties. In contrast, PETase does not degrade aliphatic polyesters, suggesting that it is generally an aromatic polyesterase. These findings suggest that additional protein engineering to increase PETase performance is realistic and highlight the need for further developments of structure/activity relationships for biodegradation of synthetic polyesters. PMID:29666242
Characterization and engineering of a plastic-degrading aromatic polyesterase

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

Austin, Harry P.; Allen, Mark D.; Donohoe, Bryon S.

Poly(ethylene terephthalate) (PET) is one of the most abundantly produced synthetic polymers and is accumulating in the environment at a staggering rate as discarded packaging and textiles. The properties that make PET so useful also endow it with an alarming resistance to biodegradation, likely lasting centuries in the environment. Our collective reliance on PET and other plastics means that this buildup will continue unless solutions are found. Recently, a newly discovered bacterium, Ideonella sakaiensis 201-F6, was shown to exhibit the rare ability to grow on PET as a major carbon and energy source. Central to its PET biodegradation capability ismore » a secreted PETase (PET-digesting enzyme). Here, we present a 0.92 A resolution X-ray crystal structure of PETase, which reveals features common to both cutinases and lipases. PETase retains the ancestral a/..beta..-hydrolase fold but exhibits a more open active-site cleft than homologous cutinases. By narrowing the binding cleft via mutation of two active-site residues to conserved amino acids in cutinases, we surprisingly observe improved PET degradation, suggesting that PETase is not fully optimized for crystalline PET degradation, despite presumably evolving in a PET-rich environment. Additionally, we show that PETase degrades another semiaromatic polyester, polyethylene-2,5-furandicarboxylate (PEF), which is an emerging, bioderived PET replacement with improved barrier properties. In contrast, PETase does not degrade aliphatic polyesters, suggesting that it is generally an aromatic polyesterase. These findings suggest that additional protein engineering to increase PETase performance is realistic and highlight the need for further developments of structure/activity relationships for biodegradation of synthetic polyesters.« less
Characterization and engineering of a plastic-degrading aromatic polyesterase

DOE PAGES

Austin, Harry P.; Allen, Mark D.; Donohoe, Bryon S.; ...

2018-04-17

Poly(ethylene terephthalate) (PET) is one of the most abundantly produced synthetic polymers and is accumulating in the environment at a staggering rate as discarded packaging and textiles. The properties that make PET so useful also endow it with an alarming resistance to biodegradation, likely lasting centuries in the environment. Our collective reliance on PET and other plastics means that this buildup will continue unless solutions are found. Recently, a newly discovered bacterium, Ideonella sakaiensis 201-F6, was shown to exhibit the rare ability to grow on PET as a major carbon and energy source. Central to its PET biodegradation capability ismore » a secreted PETase (PET-digesting enzyme). Here, we present a 0.92 A resolution X-ray crystal structure of PETase, which reveals features common to both cutinases and lipases. PETase retains the ancestral a/..beta..-hydrolase fold but exhibits a more open active-site cleft than homologous cutinases. By narrowing the binding cleft via mutation of two active-site residues to conserved amino acids in cutinases, we surprisingly observe improved PET degradation, suggesting that PETase is not fully optimized for crystalline PET degradation, despite presumably evolving in a PET-rich environment. Additionally, we show that PETase degrades another semiaromatic polyester, polyethylene-2,5-furandicarboxylate (PEF), which is an emerging, bioderived PET replacement with improved barrier properties. In contrast, PETase does not degrade aliphatic polyesters, suggesting that it is generally an aromatic polyesterase. These findings suggest that additional protein engineering to increase PETase performance is realistic and highlight the need for further developments of structure/activity relationships for biodegradation of synthetic polyesters.« less
Shedding Light on Engineering Design

ERIC Educational Resources Information Center

Capobianco, Brenda M.; Nyquist, Chell; Tyrie, Nancy

2013-01-01

This article describes the steps incorporated to teach an engineering design process in a fifth-grade science classroom. The engineering design-based activity was an existing scientific inquiry activity using UV light--detecting beads and purposefully creating a series of engineering design-based challenges around the investigation. The…
Gender and grade level differences in interest, perceived personal capacity, and involvement in technology and engineering-related activities

NASA Astrophysics Data System (ADS)

Weber, Katherine

Society has become increasingly technological, demanding that all citizens have a level of technological literacy. In order for this to occur, both males and females must participate in technology-related activities to achieve an adequate level of technological literacy. Despite individual and organizational efforts, females continue to be underrepresented in STEM-related occupations. This is especially true in many engineering-related fields. Jolly, Campbell and Perlman (2004) devised the Engagement, Capacity, and Continuity (ECC) Trilogy. With each factor of the trilogy in place, Jolly et al. found that female representation increased in STEM. The purpose of this study was to identify whether Jolly, Campbell, and Perlman's (2004) Engagement, Capacity, and Continuity Trilogy could be utilized by teachers in technology and engineering program settings to examine their students' interest (engagement), perceived personal capacity (capacity), as well as participation in technology and engineering-related activities (continuity). This descriptive study surveyed 556 female and male middle school and high school students enrolled in Technology and Engineering classes. The results of this study revealed that when students indicated a high interest and a high perceived personal capacity, and when they participated in technology and engineering-related activities, they also indicated an interest in pursuing a career in engineering. The results also revealed that the male students continued to be encouraged by technology and engineering teachers, parents, and counselors to pursue a career in engineering more than female students. This startling finding should draw some concern; both males and females should be equally encouraged to consider engineering as a career. Technology and engineering teachers should implement activities that appeal to both males and females. Parents should encourage their daughters to participate in informal learning opportunities to nurture their daughters' interest in STEM-related areas. Counselors should gain an awareness of the scope and diversity of different engineering fields so they can advise both male and female students to consider careers in engineering. In order for the United States to be competitive and innovative at the global level, female representation and contributions in STEM fields must increase. Key Words: GENDER, ENGAGEMENT, INTEREST, PERCEIVED PERSONAL CAPACITY, TECHNOLOGY AND ENGINEERING ACTIVITIES, WISCONSIN, STEM, AFTERSCHOOL ACTIVITIES.
Effects of Engineering Design-Based Science on Elementary School Science Students' Engineering Identity Development across Gender and Grade

NASA Astrophysics Data System (ADS)

Capobianco, Brenda M.; Yu, Ji H.; French, Brian F.

2015-04-01

The integration of engineering concepts and practices into elementary science education has become an emerging concern for science educators and practitioners, alike. Moreover, how children, specifically preadolescents (grades 1-5), engage in engineering design-based learning activities may help science educators and researchers learn more about children's earliest identification with engineering. The purpose of this study was to examine the extent to which engineering identity differed among preadolescents across gender and grade, when exposing students to engineering design-based science learning activities. Five hundred fifty preadolescent participants completed the Engineering Identity Development Scale (EIDS), a recently developed measure with validity evidence that characterizes children's conceptions of engineering and potential career aspirations. Data analyses of variance among four factors (i.e., gender, grade, and group) indicated that elementary school students who engaged in the engineering design-based science learning activities demonstrated greater improvements on the EIDS subscales compared to those in the comparison group. Specifically, students in the lower grade levels showed substantial increases, while students in the higher grade levels showed decreases. Girls, regardless of grade level and participation in the engineering learning activities, showed higher scores in the academic subscale compared to boys. These findings suggest that the integration of engineering practices in the science classroom as early as grade one shows potential in fostering and sustaining student interest, participation, and self-concept in engineering and science.
Microbial Consortia Engineering for Cellular Factories: in vitro to in silico systems

PubMed Central

Bernstein, Hans C; Carlson, Ross P

2012-01-01

This mini-review discusses the current state of experimental and computational microbial consortia engineering with a focus on cellular factories. A discussion of promising ecological theories central to community resource usage is presented to facilitate interpretation of consortial designs. Recent case studies exemplifying different resource usage motifs and consortial assembly templates are presented. The review also highlights in silico approaches to design and to analyze consortia with an emphasis on stoichiometric modeling methods. The discipline of microbial consortia engineering possesses a widely accepted potential to generate highly novel and effective bio-catalysts for applications from biofuels to specialty chemicals to enhanced mineral recovery. PMID:24688677
Analysis of pre-heated fuel combustion and heat-emission dynamics in a diesel engine

NASA Astrophysics Data System (ADS)

Plotnikov, S. A.; Kartashevich, A. N.; Buzikov, S. V.

2018-01-01

The article explores the feasibility of diesel fuel pre-heating. The research goal was to obtain and analyze the performance diagrams of a diesel engine fed with pre-heated fuel. The engine was tested in two modes: at rated RPMs and at maximum torque. To process the diagrams the authors used technique developed by the Central Diesel Research Institute (CDRI). The diesel engine’s heat emission curves were obtained. The authors concluded that fuel pre-heating shortened the initial phase of the combustion process and moderated the loads, thus making it possible to boost a diesel engine’s mean effective pressure.
Engineering microbial fatty acid metabolism for biofuels and biochemicals.

PubMed

Marella, Eko Roy; Holkenbrink, Carina; Siewers, Verena; Borodina, Irina

2018-04-01

Traditional oleochemical industry chemically processes animal fats and plant oils to produce detergents, lubricants, biodiesel, plastics, coatings, and other products. Biotechnology offers an alternative process, where the same oleochemicals can be produced from abundant biomass feedstocks using microbial catalysis. This review summarizes the recent advances in the engineering of microbial metabolism for production of fatty acid-derived products. We highlight the efforts in engineering the central carbon metabolism, redox metabolism, controlling the chain length of the products, and obtaining metabolites with different functionalities. The prospects of commercializing microbial oleochemicals are also discussed. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Euclea undulata Thunb.: Review of its botany, ethnomedicinal uses, phytochemistry and biological activities.

PubMed

Maroyi, Alfred

2017-11-01

Euclea undulata (E. undulata) is traditionally used for the treatment of body pains, chest complaints, cough, diabetes, diarrhoea, headaches, heart diseases and toothaches in southern Africa. This study was aimed at reviewing the botany, ethnopharmacology and biological activities of E. undulata in southern Africa. Results presented in this study are based on review of literature using search engines such as Science Direct, Springerlink, Scopus, PubMed, Web of Science, BioMed Central and Google Scholar. Herbal medicine is prepared from the decoctions of the roots, bark and leaves, and extracts of these plant parts have demonstrated anticholinesterase, anti-inflammatory, antimicrobial, antimycobacterial, antiplasmodial, antioxidant and hypoglycaemic activities. Multiple classes of phytochemical compounds such alkaloids, diterpenes, fatty acids, flavonoids, glycosides, naphthoquinones, phenolics, phytosterols, reducing sugars, saponins and tannins have been isolated from the species. E. undulata has a lot of potential as herbal medicine in tropical Africa, and advanced research is required aimed at correlating its medicinal uses with the phytochemistry and pharmacological properties. Copyright © 2017 Hainan Medical University. Production and hosting by Elsevier B.V. All rights reserved.
The Public Sector Construction Industry: Analysis of Single-Project Partnering

DTIC Science & Technology

1992-12-22

thesis advisor, Dr. Fred Moavenzadeh for his guidance and encouragement. Colonel Larry S. Bonine , U.S. Army (Retired) and the members of his Partnering...PROJECT (CkG) ENGINEERS MANAGERS PR::JECT PARINERING TEAM Figure 4-4. Central Artery/Tunnel Organizational Chart. 116 MR. Larry Bonine an employee of the...joint venture team. MR. Bonine is an ex-Army Colonel and was the Corps District Engineer in Mobile, Alabama who oversaw the Oliver Lock and Dam and
Hot gas engine heater head

DOEpatents

Berntell, John O.

1983-01-01

A heater head for a multi-cylinder double acting hot gas engine in which each cylinder is surrounded by an annular regenerator unit, and in which the tops of each cylinder and its surrounding regenerator are interconnected by a multiplicity of heater tubes. A manifold for the heater tubes has a centrally disposed duct connected to the top of the cylinder and surrounded by a wider duct connecting the other ends of the heater tubes with the regenerator unit.
Crew Earth Observations (CEO) by Expedition Five Crew

NASA Image and Video Library

2002-09-16

ISS005- E-15375 (22 September 2002) --- This digital still camera's picture, taken from the International Space Station (ISS) on September 22, 2002, shows the central eye of Hurricane Isidore. The eye become less defined as the hurricane stalled and weakened over the Yucatan Peninsula near Merida. Onboard the orbital outpost for the Expedition Five mission are cosmonauts Valery G. Korzun, commander, and Sergei Y. Treschev, flight engineer, both with Rosaviakosmos; and astronaut Peggy A. Whitson, flight engineer.
Coupling ligand recognition to protein folding in an engineered variant of rabbit ileal lipid binding protein.

PubMed

Kouvatsos, Nikolaos; Meldrum, Jill K; Searle, Mark S; Thomas, Neil R

2006-11-28

We have engineered a variant of the beta-clam shell protein ILBP which lacks the alpha-helical motif that caps the central binding cavity; the mutant protein is sufficiently destabilised that it is unfolded under physiological conditions, however, it unexpectedly binds its natural bile acid substrates with high affinity forming a native-like beta-sheet rich structure and demonstrating strong thermodynamic coupling between ligand binding and protein folding.
Pilot Specialists--The Potential for Dual-Track Personnel Management of U.S. Air Force Pilots

DTIC Science & Technology

1980-06-06

1976 MA, Management and Supervision, Central Michigan University (Extension), Washington, D.C. 1969 BS, Aeronautical Engineering , United States Air ...of Naval Research May 1976. 9C .. .. 64. Thomas, James M. "Retention of Scientists and Engineers -• in the Air Force; A modified Model for Interpreting...CATALOG NUMBER 4. __(mu #btle)S. TYPE OF REPORT & PERIOD COVERED Track Personnel Management-of U.*S. Air Force Pilots S. PERFORMING ORG. REPORT NUMBE 7
Systemic Administration of the Potential Countermeasure Huperzine Reversibly Inhibits Central and Peripheral Acetylcholinesterase Activity Without Adverse Cognitive-Behavioral Effects

DTIC Science & Technology

2010-01-01

reversibly inhibits 5a. CONTRACT NUMBER central and peripheral acetylcholinesterase activity without adverse cognitive–behavioral effects 5b. GRANT...huperzine reversibly inhibits central and peripheral acetylcholinesterase activity without adverse cognitive–behavioral effects Todd M. Myers a,⁎, Wei Sun b...HUP to enter the brain is also evidenced by studies that use well-documented centrally active anticholinergics to induce cognitive impairments that are
NASA Image eXchange (NIX)

NASA Technical Reports Server (NTRS)

vonOfenheim. William H. C.; Heimerl, N. Lynn; Binkley, Robert L.; Curry, Marty A.; Slater, Richard T.; Nolan, Gerald J.; Griswold, T. Britt; Kovach, Robert D.; Corbin, Barney H.; Hewitt, Raymond W.

1998-01-01

This paper discusses the technical aspects of and the project background for the NASA Image exchange (NIX). NIX, which provides a single entry point to search selected image databases at the NASA Centers, is a meta-search engine (i.e., a search engine that communicates with other search engines). It uses these distributed digital image databases to access photographs, animations, and their associated descriptive information (meta-data). NIX is available for use at the following URL: http://nix.nasa.gov./NIX, which was sponsored by NASAs Scientific and Technical Information (STI) Program, currently serves images from seven NASA Centers. Plans are under way to link image databases from three additional NASA Centers. images and their associated meta-data, which are accessible by NIX, reside at the originating Centers, and NIX utilizes a virtual central site that communicates with each of these sites. Incorporated into the virtual central site are several protocols to support searches from a diverse collection of database engines. The searches are performed in parallel to ensure optimization of response times. To augment the search capability, browse functionality with pre-defined categories has been built into NIX, thereby ensuring dissemination of 'best-of-breed' imagery. As a final recourse, NIX offers access to a help desk via an on-line form to help locate images and information either within the scope of NIX or from available external sources.
Gene transfer to brain using herpes simplex virus vectors.

PubMed

Glorioso, J C; Goins, W F; Meaney, C A; Fink, D J; DeLuca, N A

1994-01-01

Herpes simplex virus type 1 represents an ideal candidate for development as a vehicle for gene transfer to postmitotic neurons of the central nervous system. The natural biology of this virus makes it well suited for this purpose as it is capable of infecting a variety of neuronal cell types in the brain where the viral genome can persist indefinitely in a latent state. In latency, the viral lytic genes are transcriptionally silent and a unique set of latency-associated transcripts are expressed. Two impediments to using herpes simplex virus vectors must be overcome: (1) A noncytotoxic mutant virus backbone must be engineered, and (2) a suitable promoter-regulator that stably expresses foreign genes from the vector genome during latency must be constructed. Deletion of specific immediate early genes from the vector can render the virus nontoxic to neurons in culture and in vivo following stereotactic inoculation into specific regions of the brain. Because these viruses cannot replicate, they enter latency on infection of central nervous system neurons. A number of viral and cellular promoters have been tested for their ability to express genes during latency. Strong viral promoters and neurospecific promoters display transient activity. Although the promoter regions for the latency-associated transcripts are highly active in the peripheral nervous system, they show low-level but persistent activity in the brain. Experiments are in progress to exploit RNA polymerase III gene promoters or novel recombinant promoters capable of auto-inducing their own expression in order to increase gene expression during latency in brain neurons.
Dual-Actuator Active Vibration-Control System

NASA Technical Reports Server (NTRS)

Kascak, Albert F.; Kiraly, Louis J.; Montague, Gerald T.; Palazzolo, Alan B.; Manchala, Daniel

1994-01-01

Dual-actuator active vibration-control (DAAVC) system is developmental system of type described in "Active Vibration Dampers for Rotating Machinery" (LEW-15427). System features sensors and actuators positioned and oriented at bearings to measure and counteract vibrations of shaft along either of two axes perpendicular to axis of rotation. Effective in damping vibrations of helicopter-engine test stand, making it safer to operate engine at speeds near and above first resonance of engine/test-stand system. Opens new opportunities for engine designers to draw more power from engine, and concept applicable to other rotating machines.
Exploring Young Children's Understanding about the Concept of Volume through Engineering Design in a STEM Activity: A Case Study

ERIC Educational Resources Information Center

Park, Do-Yong; Park, Mi-Hwa; Bates, Alan B.

2018-01-01

This case study explores young children's understanding and application of the concept of volume through the practices of engineering design in a STEM activity. STEM stands for science, technology, engineering, and mathematics. However, engineering stands out as a challenging area to implement. In addition, most early engineering education…

Table-Top Robotics for Engineering Design

ERIC Educational Resources Information Center

Wilczynski, Vincent; Dixon, Gregg; Ford, Eric

2005-01-01

The Mechanical Engineering Section at the U.S. Coast Guard Academy has developed a comprehensive activity based course to introduce second year students to mechanical engineering design. The culminating design activity for the course requires students to design, construct and test robotic devices that complete engineering challenges. Teams of…
A numerical study on the effect of various combustion bowl parameters on the performance, combustion, and emission behavior on a single cylinder diesel engine.

PubMed

Balasubramanian, Dhinesh; Sokkalingam Arumugam, Sabari Rajan; Subramani, Lingesan; Joshua Stephen Chellakumar, Isaac JoshuaRamesh Lalvani; Mani, Annamalai

2018-01-01

A numerical study was carried out to study the effect of various combustion bowl parameters on the performance behavior, combustion characteristics, and emission magnitude on a single cylinder diesel engine. A base combustion bowl and 11 different combustion bowls were created by varying the aspect ratio, reentrancy ratio, and bore to bowl ratio. The study was carried out at engine rated speed and a full throttle performance condition, without altering the compression ratio. The results revealed that the combustion bowl parameters could have a huge impact on the performance behavior, combustion characteristics, and emission magnitude of the engine. The bowl parameters, namely throat diameter and toroidal radius, played a crucial role in determining the performance behavior of the combustion bowls. It was observed that the combustion bowl parameters, namely central pip distance, throat diameter, and bowl depth, also could have an impact on the combustion characteristics. And throat diameter and toroidal radius, central pip distance, and toroidal corner radius could have a consequent effect on the emission magnitude of the engine. Of the different combustion bowls tested, combustion bowl 4 was preferable to others owing to the superior performance of 3% of higher indicated mean effective pressure and lower fuel consumption. Interestingly, trade-off for NO x emission was higher only by 2.85% compared with the base bowl. The sensitivity analysis proved that bowl depth, bowl diameter, toroidal radius, and throat diameter played a vital role in the fuel consumption parameter and emission characteristics even at the manufacturing tolerance variations.
Noninvasive Methods for Determining Lesion Depth from Vesicant Exposure

DTIC Science & Technology

2007-01-01

LDPI. Chilcott et al19 used several noninvasive bio- a bolus through a central or peripheral venous line. engineering methods to monitor wound healing...ade- bolus through a central or peripheral venous line. The quate NBF into the tissue, two parallel cuts approxi- first two range finding pigs were...not more than 5.0%), its use creasing the size of the scan area, and/or decreasing is contraindicated in patients with a history of allergy the number
The ATCA CABB Line Survey on Centaurus A: Properties of the Molecular Gas from the Dust Lanes to the Central Engine

NASA Astrophysics Data System (ADS)

Ott, Juergen; Henkel, Christian; Meier, David; Feain, Ilana; Martin-Pintado, Jesus; Israel, Frank; Impellizzeri, Caterina M. V.

2011-04-01

Centaurus A with its host NGC5128 is the most nearby radio galaxy. Its molecular spectrum exhibits three prominent features: a) gas that is located in the outer disk and dust lanes, b) absorption lines that are supposedly close to the central AGN, and c) gas in emission from the central nucleus. We propose to perform an extensive line survey toward CenA using the exciting new capabilities of CABB. Our multi-band line observations will allow us to derive the exact physical conditions of each component as well as the chemistry involved.
Integrating Literacy and Engineering Instruction for Young Learners

ERIC Educational Resources Information Center

Wilson-Lopez, Amy; Gregory, Stacie

2015-01-01

According to recently published national standards, elementary students should engage in engineering design activities. This article outlines ways that teachers can use literacy instruction to support young students' engineering design activity, such as by selecting texts in which characters face problems that can be solved through engineering,…
Army/NASA small turboshaft engine digital controls research program

NASA Technical Reports Server (NTRS)

Sellers, J. F.; Baez, A. N.

1981-01-01

The emphasis of a program to conduct digital controls research for small turboshaft engines is on engine test evaluation of advanced control logic using a flexible microprocessor based digital control system designed specifically for research on advanced control logic. Control software is stored in programmable memory. New control algorithms may be stored in a floppy disk and loaded directly into memory. This feature facilitates comparative evaluation of different advanced control modes. The central processor in the digital control is an Intel 8086 16 bit microprocessor. Control software is programmed in assembly language. Software checkout is accomplished prior to engine test by connecting the digital control to a real time hybrid computer simulation of the engine. The engine currently installed in the facility has a hydromechanical control modified to allow electrohydraulic fuel metering and VG actuation by the digital control. Simulation results are presented which show that the modern control reduces the transient rotor speed droop caused by unanticipated load changes such as cyclic pitch or wind gust transients.
Reverse engineering and identification in systems biology: strategies, perspectives and challenges.

PubMed

Villaverde, Alejandro F; Banga, Julio R

2014-02-06

The interplay of mathematical modelling with experiments is one of the central elements in systems biology. The aim of reverse engineering is to infer, analyse and understand, through this interplay, the functional and regulatory mechanisms of biological systems. Reverse engineering is not exclusive of systems biology and has been studied in different areas, such as inverse problem theory, machine learning, nonlinear physics, (bio)chemical kinetics, control theory and optimization, among others. However, it seems that many of these areas have been relatively closed to outsiders. In this contribution, we aim to compare and highlight the different perspectives and contributions from these fields, with emphasis on two key questions: (i) why are reverse engineering problems so hard to solve, and (ii) what methods are available for the particular problems arising from systems biology?
Harnessing the power of macrophages/monocytes for enhanced bone tissue engineering.

PubMed

Dong, Lei; Wang, Chunming

2013-06-01

Bone tissue engineering has attracted considerable attention as a promising treatment modality for severe bone degeneration. The pressing need for more sophisticated and fully functional bone substitutes has spurred a refocus on the development of bone constructs in a way more comparable to the physiological process. Current research is increasingly revealing the central roles of macrophages/monocytes in regulating bone development and repair, so we propose that these immunocytes can play a similar pivotal role in directing engineered bone regeneration. Accordingly, we discuss two possible strategies to exemplify how the distinctive power of macrophages/monocytes--particularly their cytokine-secretion ability and chemotactic response to foreign materials--can be harnessed to enhance the performance of bone tissue engineering applications. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Hispanic Heritage Month Employee Profile- Gustavo Martinez - Marshall Space Flight Center

NASA Image and Video Library

2016-10-19

In observance of National Hispanic Heritage Month, Gustavo Martinez, a propulsion engineer at NASA’s Marshall Space Flight Center, is featured in this video profile. Martinez, a first-generation American of Mexican descent, earned his bachelors and masters in mechanical engineering from the University of Texas at El Paso. He works in the Liquid Engine System Branch of Marshall’s Propulsion Systems Department, supporting RS-25 engine systems analysis and test preparations for NASA’s Space Launch System. National Hispanic Heritage Month honors the cultures and contributions of Americans whose ancestors originated from Spain, Mexico, the Caribbean and Central and South America. The observation started in 1968 as Hispanic Heritage Week under President Lyndon Johnson and was expanded into law by President Ronald Reagan in 1988.
78 FR 9455 - Rehabilitation Research and Development Service Scientific Merit Review Board, Notice of Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-08

.... Rehabilitation Engineering and February 20, 2013 Courtyard DC/U.S. Prosthetics/Orthotics. Capitol. Brain Injury.... Career Development Award February 26-28, *VA Central Office. Program and Research Career 2013. Scientists...
A water-vapour giga-maser in the active galaxy TXFS2226-184.

PubMed

Koekemoer, A M; Henkel, C; Greenhill, L J; Dey, A; van Breugel, W; Codella, C; Antonucci, R

1995-12-14

Active galactic nuclei are thought to be powered by gas falling into a massive black hole; the different types of active galaxy may arise because we view them through a thick torus of molecular gas at varying angles of inclination. One way to determine whether the black hole is surrounded by a torus, which would obscure the accretion disk around the black hole along certain lines of sight, is to search for water masers, as these exist only in regions with plentiful molecular gas. Since the first detection of an extra-galactic water maser in 1979, they have come to be associated primarily with active galaxies, and have even been used to probe the mass of the central engine. Here we report the detection of a water giga-maser in the radio galaxy TXFS2226-184. The strength of the emission supports a recently proposed theory of maser pumping that allows for even more powerful masers, which might be detectable at cosmological distances. Water masers may accordingly provide a way to determine distances to galaxies outside the usual distance ladder, providing an independent calibration of the Hubble constant.
Control and protection system for an installation for the combined production of electrical and thermal energy

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

Agazzone, U.; Ausiello, F.P.

1981-06-23

A power-generating installation comprises a plurality of modular power plants each comprised of an internal combustion engine connected to an electric machine. The electric machine is used to start the engine and thereafter operates as a generator supplying power to an electrical network common to all the modular plants. The installation has a control and protection system comprising a plurality of control modules each associated with a respective plant, and a central unit passing control signals to the modules to control starting and stopping of the individual power plants. Upon the detection of abnormal operation or failure of its associatedmore » power plant, each control module transmits an alarm signal back to the central unit which thereupon stops, or prevents the starting, of the corresponding power plant. Parameters monitored by each control module include generated current and inter-winding leakage current of the electric machine.« less
Prediction of in-use emissions of heavy-duty diesel vehicles from engine testing.

PubMed

Yanowitz, Janet; Graboski, Michael S; McCormick, Robert L

2002-01-15

A model of a heavy-duty vehicle driveline with automatic transmission has been developed for estimating engine speed and load from vehicle speed. The model has been validated using emissions tests conducted on three diesel vehicles on a chassis dynamometer and then on the engines removed from the vehicles tested on an engine dynamometer. Nitrogen oxide (NOx) emissions were proportional to work done by the engine. For two of the engines, the NOx/horsepower(HP) ratio was the same on the engine and on the chassis dynamometer tests. For the third engine NOx/HP was significantly higher from the chassis test, possibly due to the use of dual engine maps. The engine certification test generated consistently less particulate matter emissions on a gram per brake horsepower-hour basis than the Heavy Duty Transient and Central Business District chassis cycles. A good linear correlation (r2 = 0.97 and 0.91) was found between rates of HP increase integrated over the test cycle and PM emissions for both the chassis and the engine tests for two of the vehicles. The model also shows how small changes in vehicle speeds can lead to a doubling of load on the engine. Additionally, the model showed that it is impossible to drive a vehicle cycle equivalent to the heavy-duty engine federal test procedure on these vehicles.
Centrality and Flow Vergence gradient based Path analysis of scientific literature: A case study of Biotechnology for Engineering

NASA Astrophysics Data System (ADS)

Lathabai, Hiran H.; Prabhakaran, Thara; Changat, Manoj

2015-07-01

Biotechnology, ever since its inception has had a huge impact on the society and its various applications have been intricately woven into the human web of life. Its evolution amidst all the other research realms vital to mankind is remarkable. In this paper, we intend to identify the radical innovations in Biotechnology for Engineering using network analyses. Centrality analysis and Path analysis are used for identifying important works. Existence of Flow Vergence effect in the scientific literature is revealed. Flow Vergence gradient, an arc metric derived from FV model, is utilised for Path analysis which detects pivotal papers of paradigm shift more accurately. A major paradigm shift has been identified in the business models of Biotechnology for Engineering - 'Capability to Connectivity' model. Evidence towards the adoption of business practices in BT firms by nanotechnology start-ups is also identified. The notion of critical divergence is introduced and the exhibition of interdisciplinary interaction in emerging fields due to critical divergence is discussed. Implications of above analyses which target: (i) Science and technology policy makers, (ii) industrialists and investors, (iii) researchers in academia as well as industry, are also discussed.
Elucidation of new condition-dependent roles for fructose-1,6-bisphosphatase linked to cofactor balances

PubMed Central

Kilian, Stephanus G.; du Preez, James C.

2017-01-01

The cofactor balances in metabolism is of paramount importance in the design of a metabolic engineering strategy and understanding the regulation of metabolism in general. ATP, NAD+ and NADP+ balances are central players linking the various fluxes in central metabolism as well as biomass formation. NADP+ is especially important in the metabolic engineering of yeasts for xylose fermentation, since NADPH is required by most yeasts in the initial step of xylose utilisation, including the fast-growing Kluyveromyces marxianus. In this simulation study of yeast metabolism, the complex interplay between these cofactors was investigated; in particular, how they may affect the possible roles of fructose-1,6-bisphosphatase, the pentose phosphate pathway, glycerol production and the pyruvate dehydrogenase bypass. Using flux balance analysis, it was found that the potential role of fructose-1,6-bisphosphatase was highly dependent on the cofactor specificity of the oxidative pentose phosphate pathway and on the carbon source. Additionally, the excessive production of ATP under certain conditions might be involved in some of the phenomena observed, which may have been overlooked to date. Based on these findings, a strategy is proposed for the metabolic engineering of a future xylose-fermenting yeast for biofuel production. PMID:28542187
Cooling Timescale of Dust Tori in Dying Active Galactic Nuclei

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

Ichikawa, Kohei; Tazaki, Ryo, E-mail: k.ichikawa@astro.columbia.edu

We estimate the dust torus cooling timescale once the active galactic nucleus (AGN) is quenched. In a clumpy torus system, once the incoming photons are suppressed, the cooling timescale of one clump from T {sub dust} = 1000 K to several 10 K is less than 10 years, indicating that the dust torus cooling time is mainly governed by the light crossing time of the torus from the central engine. After considering the light crossing time of the torus, the AGN torus emission at 12 μ m becomes over two orders of magnitude fainter within 100 years after the quenching.more » We also propose that those “dying” AGNs could be found using the AGN indicators with a different physical scale R such as 12 μ m band luminosity tracing AGN torus ( R ∼ 10 pc) and the optical [O iii] λ 5007 emission line tracing narrow line regions ( R = 10{sup 2–4} pc).« less
What Fraction of Active Galaxies Actually Show Outflows?

NASA Astrophysics Data System (ADS)

Ganguly, Rajib; Brotherton, M. S.

2007-12-01

Outflows from active galactic nuclei (AGNs) seem to be common and are thought to be important from a variety of perspectives: as an agent of chemical enhancement of the interstellar and intergalactic media, as an agent of angular momentum removal from the accreting central engine, and as an agent limiting star formation in starbursting systems by blowing out gas and dust from the host galaxy. To understand these processes, we must determine what fraction of AGNs feature outflows and understand what forms they take. We examine recent surveys of outflows detected in ultraviolet absorption over the entire range of velocities and velocity widths (i.e., broad absorption lines, associated absorption lines, and high-velocity narrow absorption lines). While the fraction of specific forms of outflows depends on AGN properties, the overall fraction displaying outflows is fairly constant, approximately 60%, over many orders of magnitude in luminosity. We discuss implications of this result and ways to refine our understanding of outflows. We acknowledge support from the US National Science Foundation through grant AST 05-07781.
Accretion-induced variability links young stellar objects, white dwarfs, and black holes.

PubMed

Scaringi, Simone; Maccarone, Thomas J; Körding, Elmar; Knigge, Christian; Vaughan, Simon; Marsh, Thomas R; Aranzana, Ester; Dhillon, Vikram S; Barros, Susana C C

2015-10-01

The central engines of disc-accreting stellar-mass black holes appear to be scaled down versions of the supermassive black holes that power active galactic nuclei. However, if the physics of accretion is universal, it should also be possible to extend this scaling to other types of accreting systems, irrespective of accretor mass, size, or type. We examine new observations, obtained with Kepler/K2 and ULTRACAM, regarding accreting white dwarfs and young stellar objects. Every object in the sample displays the same linear correlation between the brightness of the source and its amplitude of variability (rms-flux relation) and obeys the same quantitative scaling relation as stellar-mass black holes and active galactic nuclei. We also show that the most important parameter in this scaling relation is the physical size of the accreting object. This establishes the universality of accretion physics from proto-stars still in the star-forming process to the supermassive black holes at the centers of galaxies.
Accretion-induced variability links young stellar objects, white dwarfs, and black holes

PubMed Central

Scaringi, Simone; Maccarone, Thomas J.; Körding, Elmar; Knigge, Christian; Vaughan, Simon; Marsh, Thomas R.; Aranzana, Ester; Dhillon, Vikram S.; Barros, Susana C. C.

2015-01-01

The central engines of disc-accreting stellar-mass black holes appear to be scaled down versions of the supermassive black holes that power active galactic nuclei. However, if the physics of accretion is universal, it should also be possible to extend this scaling to other types of accreting systems, irrespective of accretor mass, size, or type. We examine new observations, obtained with Kepler/K2 and ULTRACAM, regarding accreting white dwarfs and young stellar objects. Every object in the sample displays the same linear correlation between the brightness of the source and its amplitude of variability (rms-flux relation) and obeys the same quantitative scaling relation as stellar-mass black holes and active galactic nuclei. We also show that the most important parameter in this scaling relation is the physical size of the accreting object. This establishes the universality of accretion physics from proto-stars still in the star-forming process to the supermassive black holes at the centers of galaxies. PMID:26601307
Integrated Model-Based Controls and PHM for Improving Turbine Engine Performance, Reliability, and Cost

DTIC Science & Technology

2009-09-01

capable of surviving the high-temperature, high- vibration environment of a jet engine. Active control spans active surge/stall control and three...other closely related areas, viz., active combustion control (references 21-22), active noise control, and active vibration control. All of these are...self-powered sensors that harvest energy from engine heat or vibrations replace sensors that require power. The long-term vision is one of a

13C metabolic flux analysis: optimal design of isotopic labeling experiments.

PubMed

Antoniewicz, Maciek R

2013-12-01

Measuring fluxes by 13C metabolic flux analysis (13C-MFA) has become a key activity in chemical and pharmaceutical biotechnology. Optimal design of isotopic labeling experiments is of central importance to 13C-MFA as it determines the precision with which fluxes can be estimated. Traditional methods for selecting isotopic tracers and labeling measurements did not fully utilize the power of 13C-MFA. Recently, new approaches were developed for optimal design of isotopic labeling experiments based on parallel labeling experiments and algorithms for rational selection of tracers. In addition, advanced isotopic labeling measurements were developed based on tandem mass spectrometry. Combined, these approaches can dramatically improve the quality of 13C-MFA results with important applications in metabolic engineering and biotechnology. Copyright © 2013 Elsevier Ltd. All rights reserved.
On the internal structure of relativistic jets collimated by ambient gas pressure

NASA Astrophysics Data System (ADS)

Beskin, V. S.; Chernoglazov, A. V.; Kiselev, A. M.; Nokhrina, E. E.

2017-12-01

Recent progress in very long baseline interferometry (VLBI) observations of relativistic jets outflowing from active galactic nuclei gives us direct information about jet width rjet(l) dependence on the distance l from the 'central engine'. Being the missing link in previous works, this relation opens the possibility of determining the internal structure of a jet. In this article, we consider a relativistic jet submerged in an external medium with finite gas pressure Pext. Neither an external magnetic field nor an infinitely thin current sheet will be assumed. This approach allows us to construct a reasonable solution in which both the magnetic field and the flow velocity vanish at the jet boundary r = rjet. In particular, the connection between external gas pressure and internal structure of a relativistic jet is determined.
A tactile paging system for deaf-blind people, phase 1. [human factors engineering of bioinstrumentation

NASA Technical Reports Server (NTRS)

Baer, J. A.

1976-01-01

A tactile paging system for deaf-blind people has been brought from the concept stage to the development of a first model. The model consists of a central station that transmits coded information via radio link to an on-body (i.e., worn on the wrist) receiving unit, the output from which is a coded vibrotactile signal. The model is a combination of commercially available equipment, customized electronic circuits, and electromechanical transducers. The paging system facilitates communication to deaf-blind clients in an institutional environment as an aid in their training and other activities. Several subunits of the system were individually developed, tested, and integrated into an operating system ready for experimentation and evaluation. The operation and characteristics of the system are described and photographs are shown.
Design rules for biomolecular adhesion: lessons from force measurements.

PubMed

Leckband, Deborah

2010-01-01

Cell adhesion to matrix, other cells, or pathogens plays a pivotal role in many processes in biomolecular engineering. Early macroscopic methods of quantifying adhesion led to the development of quantitative models of cell adhesion and migration. The more recent use of sensitive probes to quantify the forces that alter or manipulate adhesion proteins has revealed much greater functional diversity than was apparent from population average measurements of cell adhesion. This review highlights theoretical and experimental methods that identified force-dependent molecular properties that are central to the biological activity of adhesion proteins. Experimental and theoretical methods emphasized in this review include the surface force apparatus, atomic force microscopy, and vesicle-based probes. Specific examples given illustrate how these tools have revealed unique properties of adhesion proteins and their structural origins.
A biotherapy based on PSCs-in-3D spheroid-ameliorated biologics depletes in vivo cancer-sustaining stem cells

PubMed Central

Zhou, Tianlin; Li, Meng; Wen, Yanjun; Lin, Xiaojuan; Xiang, Rong; Chen, Xiancheng

2015-01-01

CSCs are able to survive routine anticancer procedures and peripheral-immune attack. Here we develop and detail a framework of CSC elimination governed by 3D-biologics. Pluripotent cells-engineered 3D-biologics (PMSB) and control non-3D-biologics were prepared from placenta-based somatic stem cells (PSCs) and inoculated respectively into senile hosts bearing progressive mammary, lung, colon carcinomas and melanoma. We demonstrate that PMSB evokes in vivo central-immune microenvironment with subsequent re-expression of thymosin-α1 ~ β4 in thymic cortex-medulla borderline for rapid MHC-unrestricted renewal of γδT-dominated immunocompetence. The post-renewal γδT-subsets could accurately bind and drive CSCs into apoptosis. Finally, with central/peripheral integral microenvironment renewal and TERT/Wnt/β-catenin pathway blockade, the CSC-subsets are fully depleted, leading to substantial cure of diverse tumors by PMSB inoculation (P < 0.01), yet not by non-3D-biologics. Thus, our study may contribute to open up a new avenue for tumor remission via pluripotent cells-engineered 3D-biologics addressing quick renewal of central-thymus and peripheral immune-microenvironment. PMID:26512920
DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Tong; Xue, Li; Zhao, Xiao-Hong

Black holes (BHs) hide themselves behind various astronomical phenomena and their properties, i.e., mass and spin, are usually difficult to constrain. One leading candidate for the central engine model of gamma-ray bursts (GRBs) invokes a stellar mass BH and a neutrino-dominated accretion flow (NDAF), with the relativistic jet launched due to neutrino-anti-neutrino annihilations. Such a model gives rise to a matter-dominated fireball, and is suitable to interpret GRBs with a dominant thermal component with a photospheric origin. We propose a method to constrain BH mass and spin within the framework of this model and apply the method to the thermallymore » dominant GRB 101219B, whose initial jet launching radius, r {sub 0}, is constrained from the data. Using our numerical model of NDAF jets, we estimate the following constraints on the central BH: mass M {sub BH} ∼ 5–9 M {sub ⊙}, spin parameter a {sub *} ≳ 0.6, and disk mass 3 M {sub ⊙} ≲ M {sub disk} ≲ 4 M {sub ⊙}. Our results also suggest that the NDAF model is a competitive candidate for the central engine of GRBs with a strong thermal component.« less
Multidisciplinary Design Technology Development: A Comparative Investigation of Integrated Aerospace Vehicle Design Tools

NASA Technical Reports Server (NTRS)

Renaud, John E.; Batill, Stephen M.; Brockman, Jay B.

1999-01-01

This research effort is a joint program between the Departments of Aerospace and Mechanical Engineering and the Computer Science and Engineering Department at the University of Notre Dame. The purpose of the project was to develop a framework and systematic methodology to facilitate the application of Multidisciplinary Design Optimization (MDO) to a diverse class of system design problems. For all practical aerospace systems, the design of a systems is a complex sequence of events which integrates the activities of a variety of discipline "experts" and their associated "tools". The development, archiving and exchange of information between these individual experts is central to the design task and it is this information which provides the basis for these experts to make coordinated design decisions (i.e., compromises and trade-offs) - resulting in the final product design. Grant efforts focused on developing and evaluating frameworks for effective design coordination within a MDO environment. Central to these research efforts was the concept that the individual discipline "expert", using the most appropriate "tools" available and the most complete description of the system should be empowered to have the greatest impact on the design decisions and final design. This means that the overall process must be highly interactive and efficiently conducted if the resulting design is to be developed in a manner consistent with cost and time requirements. The methods developed as part of this research effort include; extensions to a sensitivity based Concurrent Subspace Optimization (CSSO) NMO algorithm; the development of a neural network response surface based CSSO-MDO algorithm; and the integration of distributed computing and process scheduling into the MDO environment. This report overviews research efforts in each of these focus. A complete bibliography of research produced with support of this grant is attached.
Development of industrial minerals in Colorado

USGS Publications Warehouse

Arbogast, Belinda F.; Knepper, Daniel H.; Langer, William H.; Cappa, James A.; Keller, John W.; Widmann, Beth L.; Ellefsen, Karl J.; Klein, Terry L.; Lucius, Jeffrey E.; Dersch, John S.

2011-01-01

Technology and engineering have helped make mining safer and cleaner for both humans and the environment. Inevitably, mineral development entails costs as well as benefits. Developing a mine is an environmental, engineering, and planning challenge that must conform to many Federal, State, and local regulations. Community collaboration, creative design, and best management practices of sustainability and biodiversity can be positive indicators for the mining industry. A better understanding of aesthetics, culture, economics, geology, climate, vegetation and wildlife, topography, historical significance, and regional land planning is important in resolving land-use issues and managing mineral resources wisely. Ultimately, the consuming public makes choices about product use (including water, food, highways, housing, and thousands of other items) that influence operations of the mineral industry. Land planners, resource managers, earth scientists, designers, and public groups have a responsibility to consider sound scientific information, society's needs, and community appeals in making smart decisions concerning resource use and how complex landscapes should change. An effort to provide comprehensive geosciences data for land management agencies in central Colorado was undertaken in 2003 by scientists of the U.S. Geological Survey and the Colorado Geological Survey. This effort, the Central Colorado Assessment Project, addressed a variety of land-use issues: an understanding of the availability of industrial and metallic rocks and minerals, the geochemical and environmental effects of historic mining activity on surface water and groundwater, and the geologic controls on the availability and quality of groundwater. The USDA Forest Service and other land management agencies have the opportunity to contribute to the sustainable management of natural aggregate and other mineral resources through the identification and selective development of mineral resources and the reclamation of mines on lands that they administer. The information in this Circular will help them carry out that task.
Metabolic flux phenotype of tobacco hairy roots engineered for increased geraniol production.

PubMed

Masakapalli, Shyam K; Ritala, Anneli; Dong, Lemeng; van der Krol, Alexander R; Oksman-Caldentey, Kirsi-Marja; Ratcliffe, R George; Sweetlove, Lee J

2014-03-01

The goal of this study was to characterise the metabolic flux phenotype of transgenic tobacco (Nicotiana tabacum) hairy roots engineered for increased biosynthesis of geraniol, an intermediate of the terpenoid indole alkaloid pathway. Steady state, stable isotope labelling was used to determine flux maps of central carbon metabolism for transgenic lines over-expressing (i) plastid-targeted geraniol synthase (pGES) from Valeriana officinalis, and (ii) pGES in combination with plastid-targeted geranyl pyrophosphate synthase from Arabidopsis thaliana (pGES+pGPPS), as well as for wild type and control-vector-transformed roots. Fluxes were constrained by the redistribution of label from [1-¹³C]-, [2-¹³C]- or [¹³C6]glucose into amino acids, sugars and organic acids at isotopic steady state, and by biomass output fluxes determined from the fractionation of [U-¹⁴C]glucose into insoluble polymers. No significant differences in growth and biomass composition were observed between the lines. The pGES line accumulated significant amounts of geraniol/geraniol glycosides (151±24 ng/mg dry weight) and the de novo synthesis of geraniol in pGES was confirmed by ¹³C labelling analysis. The pGES+pGPPS also accumulated geraniol and geraniol glycosides, but to lower levels than the pGES line. Although there was a distinct impact of the transgenes at the level of geraniol synthesis, other network fluxes were unaffected, reflecting the capacity of central metabolism to meet the relatively modest demand for increased precursors in the transgenic lines. It is concluded that re-engineering of the terpenoid indole alkaloid pathway will only require simultaneous manipulation of the steps producing the pathway precursors that originate in central metabolism in tissues engineered to produce at least an order of magnitude more geraniol than has been achieved so far. Copyright © 2013 Elsevier Ltd. All rights reserved.
[Comparison Analysis of Economic and Engineering Control of Industrial VOCs].

PubMed

Wang, Yu-fei; Liu, Chang-xin; Cheng, Jie; Hao, Zheng-ping; Wang, Zheng

2015-04-01

Volatile organic compounds (VOCs) pollutant has become China's major air pollutant in key urban areas like sulfur dioxide, nitrogen oxides and particulate matter. It is mainly produced from industry sectors, and engineering control is one of the most important reduction measures. During the 12th Five-Year Plan, China decides to invest 40 billion RMB to build pollution control projects in key industry sectors with annual emission reduction of 605 000 t x a(-1). It shows that China attaches a great importance to emission reduction by engineering projects and highlights the awareness of engineering reduction technologies. In this paper, a macroeconomic model, namely computable general equilibrium model, (CGE model) was employed to simulate engineering control and economic control (imposing environmental tax). We aim to compare the pros and cons of the two reduction policies. Considering the economic loss of the whole country, the environmental tax has more impacts on the economy system than engineering reduction measures. We suggest that the central government provides 7 500 RMB x t(-1) as subsidy for enterprises in industry sectors to encourage engineering reduction.
Software Engineering Improvement Activities/Plan

NASA Technical Reports Server (NTRS)

2003-01-01

bd Systems personnel accomplished the technical responsibilities for this reporting period, as planned. A close working relationship was maintained with personnel of the MSFC Avionics Department Software Group (ED14). Work accomplishments included development, evaluation, and enhancement of a software cost model, performing literature search and evaluation of software tools available for code analysis and requirements analysis, and participating in other relevant software engineering activities. Monthly reports were submitted. This support was provided to the Flight Software Group/ED 1 4 in accomplishing the software engineering improvement engineering activities of the Marshall Space Flight Center (MSFC) Software Engineering Improvement Plan.
Aerospace engineering curriculum for the 21st century

NASA Technical Reports Server (NTRS)

Simitses, George J.

1995-01-01

The second year of the study was devoted to completing the information-gathering phase of this redesign effort, using the conclusions from that activity to prepare the initial structure for the new curriculum, publicizing activities to a wider engineering forum, and preparing the department faculty (Aerospace Engineering and Engineering Mechanics at University of Cincinnati) for the roles they will play in the curriculum redesign and implementation. These activities are summarized briefly in this progress report. Attached is a paper resulting from the data acquisition of this effort, 'Educating Aerospace Engineers for the Twenty-First Century: Results of a Survey.'
SearchGUI: A Highly Adaptable Common Interface for Proteomics Search and de Novo Engines.

PubMed

Barsnes, Harald; Vaudel, Marc

2018-05-25

Mass-spectrometry-based proteomics has become the standard approach for identifying and quantifying proteins. A vital step consists of analyzing experimentally generated mass spectra to identify the underlying peptide sequences for later mapping to the originating proteins. We here present the latest developments in SearchGUI, a common open-source interface for the most frequently used freely available proteomics search and de novo engines that has evolved into a central component in numerous bioinformatics workflows.
Fuel premixing module for gas turbine engine combustor

NASA Technical Reports Server (NTRS)

Chin, Jushan (Inventor); Rizk, Nader K. (Inventor); Razdan, Mohan K. (Inventor); Marshall, Andre W. (Inventor)

2005-01-01

A fuel-air premixing module is designed to reduce emissions from a gas turbine engine. In one form, the premixing module includes a central pilot premixer module with a main premixer module positioned thereround. Each of the portions of the fuel-air premixing module include an axial inflow swirler with a plurality of fixed swirler vanes. Fuel is injected into the main premixer module between the swirler vanes of the axial inflow swirler and at an acute angle relative to the centerline of the premixing module.
jsc2012e242600

NASA Image and Video Library

2012-12-14

At the Korolev Museum at the Baikonur Cosmodrome in Kazakhstan, Expedition 34/35 Flight Engineer Chris Hadfield of the Canadian Space Agency signs a mural of a Soyuz spacecraft launch Dec. 14, 2012, part of a tradition for all space travelers launching from the Central Asian spaceport. Hadfield, Soyuz Commander Roman Romanenko and Flight Engineer Tom Marshburn of NASA will launch Dec. 19 in the Soyuz TMA-07M spacecraft from Baikonur for a five-month mission on the International Space Station. NASA/Victor Zelentsov
jsc2012e242599

NASA Image and Video Library

2012-12-14

At the Korolev Museum at the Baikonur Cosmodrome in Kazakhstan, Expedition 34/35 Flight Engineer Tom Marshburn of NASA signs a mural of a Soyuz spacecraft launch Dec. 14, 2012, part of a tradition for all space travelers launching from the Central Asian spaceport. Marshburn, Soyuz Commander Roman Romanenko and Flight Engineer Chris Hadfield of the Canadian Space Agency will launch Dec. 19 in the Soyuz TMA-07M spacecraft from Baikonur for a five-month mission on the International Space Station. NASA/Victor Zelentsov
Engineering Design Activities and Conceptual Change in Middle School Science

ERIC Educational Resources Information Center

Schnittka, Christine G.

2009-01-01

The purpose of this research was to investigate the impact of engineering design classroom activities on conceptual change in science, and on attitudes toward and knowledge about engineering. Students were given a situated learning context and a rationale for learning science in an active, inquiry-based method, and worked in small collaborative…
Design and vibration control of vehicle engine mount activated by MR fluid and piezoelectric actuator

NASA Astrophysics Data System (ADS)

Lee, D. Y.; Park, Y. K.; Choi, S. B.; Lee, H. G.

2009-07-01

An engine is one of the most dominant noise and vibration sources in vehicle systems. Therefore, in order to resolve noise and vibration problems due to engine, various types of engine mounts have been proposed. This work presents a new type of active engine mount system featuring a magneto-rheological (MR) fluid and a piezostack actuator. As a first step, six degrees-of freedom dynamic model of an in-line four-cylinder engine which has three points mounting system is derived by considering the dynamic behaviors of MR mount and piezostack mount. In the configuration of engine mount system, two MR mounts are installed for vibration control of roll mode motion whose energy is very high in low frequency range, while one piezostack mount is installed for vibration control of bounce and pitch mode motion whose energy is relatively high in high frequency range. As a second step, linear quadratic regulator (LQR) controller is synthesized to actively control the imposed vibration. In order to demonstrate the effectiveness of the proposed active engine mount, vibration control performances are evaluated under various engine operating speeds (wide frequency range).
Metabolic assessment of E. coli as a Biofactory for commercial products.

PubMed

Zhang, Xiaolin; Tervo, Christopher J; Reed, Jennifer L

2016-05-01

Metabolic engineering uses microorganisms to synthesize chemicals from renewable resources. Given the thousands of known metabolites, it is unclear what valuable chemicals could be produced by a microorganism and what native and heterologous reactions are needed for their synthesis. To answer these questions, a systematic computational assessment of Escherichia coli's potential ability to produce different chemicals was performed using an integrated metabolic model that included native E.coli reactions and known heterologous reactions. By adding heterologous reactions, a total of 1777 non-native products could theoretically be produced in E. coli under glucose minimal medium conditions, of which 279 non-native products have commercial applications. Synthesis pathways involving native and heterologous reactions were identified from eight central metabolic precursors to the 279 non-native commercial products. These pathways were used to evaluate the dependence on, and diversity of, native and heterologous reactions to produce each non-native commercial product, as well as to identify each product׳s closest central metabolic precursor. Analysis of the synthesis pathways (with 5 or fewer reaction steps) to non-native commercial products revealed that isopentenyl diphosphate, pyruvate, and oxaloacetate are the closest central metabolic precursors to the most non-native commercial products. Additionally, 4-hydroxybenzoate, tyrosine, and phenylalanine were found to be common precursors to a large number of non-native commercial products. Strains capable of producing high levels of these precursors could be further engineered to create strains capable of producing a variety of commercial non-native chemicals. Copyright © 2016 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.
LSQ14bdq: A Type Ic Super-luminous Supernova with a Double-peaked Light Curve

NASA Astrophysics Data System (ADS)

Nicholl, M.; Smartt, S. J.; Jerkstrand, A.; Sim, S. A.; Inserra, C.; Anderson, J. P.; Baltay, C.; Benetti, S.; Chambers, K.; Chen, T.-W.; Elias-Rosa, N.; Feindt, U.; Flewelling, H. A.; Fraser, M.; Gal-Yam, A.; Galbany, L.; Huber, M. E.; Kangas, T.; Kankare, E.; Kotak, R.; Krühler, T.; Maguire, K.; McKinnon, R.; Rabinowitz, D.; Rostami, S.; Schulze, S.; Smith, K. W.; Sullivan, M.; Tonry, J. L.; Valenti, S.; Young, D. R.

2015-07-01

We present data for LSQ14bdq, a hydrogen-poor super-luminous supernova (SLSN) discovered by the La Silla QUEST survey and classified by the Public ESO Spectroscopic Survey of Transient Objects. The spectrum and light curve are very similar to slow-declining SLSNe such as PTF12dam. However, detections within ˜1 day after explosion show a bright and relatively fast initial peak, lasting for ˜15 days, prior to the usual slow rise to maximum light. The broader, main peak can be fit with either central engine or circumstellar interaction models. We discuss the implications of the precursor peak in the context of these models. It is too bright and narrow to be explained as a normal 56Ni-powered SN, and we suggest that interaction models may struggle to fit the two peaks simultaneously. We propose that the initial peak may arise from the post-shock cooling of extended stellar material, and reheating by a central engine drives the second peak. In this picture, we show that an explosion energy of ˜ 2× {10}52 erg and a progenitor radius of a few hundred solar radii would be required to power the early emission. The competing engine models involve rapidly spinning magnetars (neutron stars) or fallback onto a central black hole. The prompt energy required may favor the black hole scenario. The bright initial peak may be difficult to reconcile with a compact Wolf-Rayet star as a progenitor since the inferred energies and ejected masses become unphysical.

Adaptability and Prediction of Anticipatory Muscular Activity Parameters to Different Movements in the Sitting Position.

PubMed

Chikh, Soufien; Watelain, Eric; Faupin, Arnaud; Pinti, Antonio; Jarraya, Mohamed; Garnier, Cyril

2016-08-01

Voluntary movement often causes postural perturbation that requires an anticipatory postural adjustment to minimize perturbation and increase the efficiency and coordination during execution. This systematic review focuses specifically on the relationship between the parameters of anticipatory muscular activities and movement finality in sitting position among adults, to study the adaptability and predictability of anticipatory muscular activities parameters to different movements and conditions in sitting position in adults. A systematic literature search was performed using PubMed, Science Direct, Web of Science, Springer-Link, Engineering Village, and EbscoHost. Inclusion and exclusion criteria were applied to retain the most rigorous and specific studies, yielding 76 articles, Seventeen articles were excluded at first reading, and after the application of inclusion and exclusion criteria, 23 were retained. In a sitting position, central nervous system activity precedes movement by diverse anticipatory muscular activities and shows the ability to adapt anticipatory muscular activity parameters to the movement direction, postural stability, or charge weight. In addition, these parameters could be adapted to the speed of execution, as found for the standing position. Parameters of anticipatory muscular activities (duration, order, and amplitude of muscle contractions constituting the anticipatory muscular activity) could be used as a predictive indicator of forthcoming movement. In addition, this systematic review may improve methodology in empirical studies and assistive technology for people with disabilities. © The Author(s) 2016.
Linde FUSRAP Site Remediation: Engineering Challenges and Solutions of Remedial Activities on an Active Industrial Facility - 13506

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

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

2013-07-01

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

PubMed

Nkolola, J P; Wee, E G-T; Im, E-J; Jewell, C P; Chen, N; Xu, X-N; McMichael, A J; Hanke, T

2004-07-01

For the development of human immunodeficiency virus type 1 (HIV-1) vaccines, traditional approaches inducing virus-neutralizing antibodies have so far failed. Thus the effort is now focused on elicitation of cellular immunity. We are currently testing in clinical trials in the United Kingdom and East Africa a T-cell vaccine consisting of HIV-1 clade A Gag-derived immunogen HIVA delivered in a prime-boost regimen by a DNA plasmid and modified vaccinia virus Ankara (MVA). Here, we describe engineering and preclinical development of a second immunogen RENTA, which will be used in combination with the present vaccine in a four-component DNA/HIVA-RENTA prime-MVA/HIVA-RENTA boost formulation. RENTA is a fusion protein derived from consensus HIV clade A sequences of Tat, reverse transcriptase, Nef and gp41. We inactivated the natural biological activities of the HIV components and confirmed immunogenicities of the pTHr.RENTA and MVA.RENTA vaccines in mice. Furthermore, we demonstrated in mice and rhesus monkeys broadening of HIVA-elicited T-cell responses by a parallel induction of HIVA- and RENTA-specific responses recognizing multiple HIV epitopes.
Nanoparticles in Medicine: Selected Observations and Experimental Caveats.

PubMed

Thomsen, Sharon; Pearce, John A; Giustini, Andrew; Hoopes, P Jack

2013-02-26

Medically useful nanoparticles measure 1-100 nm in at least one dimension and are engineered and manufactured for specific diagnostic and treatment applications. Most nanoparticles used currently used in medicine are engineered and manufactured for specific purposes. Medically significant nanoparticles are composed of a 1) central core that is usually the medically active component, 2) one or more layers of organic or inorganic materials that forms a capsule (corona) covering the core and 3) an outer surface layer that interacts with the environment and/or targeted cells and tissues. Effective nanoparticle function in the living, intact animal or human requires electrochemical stability necessary to bypass the reticuloendothelial system (RES) and avoid filtration through the renal glomerulus into the urine. Nanoparticles are present in "natural" as well as the manufacturing and clinical environments thus could pose as significant toxins because of their small sizes, their chemical and drug content and potential effect of causing long term disease including allergies, chronic inflammation and cancer. Currently published studies have focused on the effects of nanoparticles on cells in the extremely artificial environments of cell cultures. More clinical and preclinical studies documenting the short term and long term effects nanoparticle in the intact experimental animal and human are needed.
Nanoparticles in medicine: selected observations and experimental caveats

NASA Astrophysics Data System (ADS)

Thomsen, Sharon; Pearce, John A.; Giustini, Andrew; Hoopes, P. Jack

2013-02-01

Medically useful nanoparticles measure 1-100 nm in at least one dimension and are engineered and manufactured for specific diagnostic and treatment applications. Most nanoparticles used currently used in medicine are engineered and manufactured for specific purposes. Medically significant nanoparticles are composed of a 1) central core that is usually the medically active component, 2) one or more layers of organic or inorganic materials that forms a capsule (corona) covering the core and 3) an outer surface layer that interacts with the environment and/or targeted cells and tissues. Effective nanoparticle function in the living, intact animal or human requires electrochemical stability necessary to bypass the reticuloendothelial system (RES) and avoid filtration through the renal glomerulus into the urine. Nanoparticles are present in " natural" as well as the manufacturing and clinical environments thus could pose as significant toxins because of their small sizes, their chemical and drug content and potential effect of causing long term disease including allergies, chronic inflammation and cancer. Currently published studies have focused on the effects of nanoparticles on cells in the extremely artificial environments of cell cultures. More clinical and preclinical studies documenting the short term and long term effects nanoparticle in the intact experimental animal and human are needed.
Engineering ethics beyond engineers' ethics.

PubMed

Basart, Josep M; Serra, Montse

2013-03-01

Engineering ethics is usually focused on engineers' ethics, engineers acting as individuals. Certainly, these professionals play a central role in the matter, but engineers are not a singularity inside engineering; they exist and operate as a part of a complex network of mutual relationships between many other people, organizations and groups. When engineering ethics and engineers' ethics are taken as one and the same thing the paradigm of the ethical engineer which prevails is that of the heroic engineer, a certain model of the ideal engineer: someone both quite individualistic and strong enough to deal with all the moral challenges that could arise. We argue that this is not the best approach, at least today in our interrelated world. We have achieved a high degree of independence from nature by means of technology. In exchange for this autonomy we have become increasingly tied up with very complex systems to which we constantly delegate new tasks and powers. Concerns about safety keep growing everywhere due to the fact that now we have a sensitive awareness of the huge amount of power we are both consuming and deploying, thus, new forms of dialogue and consensus have to be incorporated at different levels, in different forums and at different times. Within these democratic channels of participation not just the needs and interests, but also the responsibilities and mutual commitments of all parties should be taken into account.
Controller partitioning for integrated flight/propulsion control implementation

NASA Technical Reports Server (NTRS)

Garg, Sanjay

1993-01-01

The notion of partitioning a centralized controller into a decentralized, hierarchical structure suitable for integrated flight/propulsion control (IFPC) implementation is discussed. A systematic procedure is developed for determining partitioned airframe and engine subsystem controllers (subcontrollers), with the desired interconnection structure, that approximate the closed-loop performance and robustness characteristics of a given centralized controller. The procedure is demonstrated by application to IFPC design for a Short Take-Off and Vertical Landing (STOVL) aircraft in the landing approach to hover transition flight phase.
Engineering Safety- and Security-Related Requirements for Software-Intensive Systems

DTIC Science & Technology

2007-05-31

University Very Large New Zoo Parking Lots Zoo Back Lots Restaurants and Shops Tropical Rainforest African SavannaChildren’s Petting Area Monkeys Great Apes...decide to ride to the Great Apes and Monkeys taxi station near the central shops and restaurants area. Mr. Smith then swipes his zoo taxi travel card...taxi station on their right, circles around the central area, and soon pulls off the Zoo Loop Line to enter the inner Great Apes and Monkeys taxi
3. DETAIL VIEW OF DIRECT DRIVE STERLING 'DOLPHIN T' MODEL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. DETAIL VIEW OF DIRECT DRIVE STERLING 'DOLPHIN T' MODEL 4 CYLINDER, GASOLINE TRACTOR-TYPE ENGINE WITH FALKBIBBY FLEXIBLE COUPLING - Central Railroad of New Jersey, Newark Bay Lift Bridge, Spanning Newark Bay, Newark, Essex County, NJ
8. View toward the northeast at the north end of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. View toward the northeast at the north end of the eastern segment of the north roundhouse. (Numbers 58, 59, and 60 are visible.) - Central Railroad of New Jersey, Engine Terminal, Jersey City, Hudson County, NJ
Arrhenius reconsidered: astrophysical jets and the spread of spores

NASA Astrophysics Data System (ADS)

Sheldon, Malkah I.; Sheldon, Robert B.

2015-09-01

In 1871, Lord Kelvin suggested that the fossil record could be an account of bacterial arrivals on comets. In 1903, Svante Arrhenius suggested that spores could be transported on stellar winds without comets. In 1984, Sir Fred Hoyle claimed to see the infrared signature of vast clouds of dried bacteria and diatoms. In 2012, the Polonnaruwa carbonaceous chondrite revealed fossilized diatoms apparently living on a comet. However, Arrhenius' spores were thought to perish in the long transit between stars. Those calculations, however, assume that maximum velocities are limited by solar winds to ~5 km/s. Herbig-Haro objects and T-Tauri stars, however, are young stars with jets of several 100 km/s that might provide the necessary propulsion. The central engine of bipolar astrophysical jets is not presently understood, but we argue it is a kinetic plasma instability of a charged central magnetic body. We show how to make a bipolar jet in a belljar. The instability is non-linear, and thus very robust to scaling laws that map from microquasars to active galactic nuclei. We scale up to stellar sizes and recalculate the viability/transit-time for spores carried by supersonic jets, to show the viability of the Arrhenius mechanism.
Engineering Approaches to Illuminating Brain Structure and Dynamics

PubMed Central

Deisseroth, Karl; Schnitzer, Mark J.

2017-01-01

Historical milestones in neuroscience have come in diverse forms, ranging from the resolution of specific biological mysteries via creative experimentation to broad technological advances allowing neuroscientists to ask new kinds of questions. The continuous development of tools is driven with a special necessity by the complexity, fragility, and inaccessibility of intact nervous systems, such that inventive technique development and application drawing upon engineering and the applied sciences has long been essential to neuroscience. Here we highlight recent technological directions in neuroscience spurred by progress in optical, electrical, mechanical, chemical, and biological engineering. These research areas are poised for rapid growth and will likely be central to the practice of neuroscience well into the future. PMID:24183010
33 CFR 384.3 - What programs and activities of the Corps of Engineers are subject to these regulations?

Code of Federal Regulations, 2010 CFR

2010-07-01

... Register a list of the Corps of Engineers Civil Works programs and activities that are subject to these... the Corps of Engineers are subject to these regulations? 384.3 Section 384.3 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE INTERGOVERNMENTAL REVIEW OF...
77 FR 75406 - Foreign-Trade Zone 26-Atlanta, GA; Notification of Proposed Production Activity; Perkins Shibaura...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-20

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [B-90-2012] Foreign-Trade Zone 26--Atlanta, GA; Notification of Proposed Production Activity; Perkins Shibaura Engines LLC, (Diesel Engines), Griffin, GA Perkins Shibaura Engines LLC (Perkins Shibaura), an operator of FTZ 26, submitted a notification of proposed production activity for its facilit...
Hydrodynamic Capture and Release of Passively Driven Particles by Active Particles Under Hele-Shaw Flows

NASA Astrophysics Data System (ADS)

Mishler, Grant; Tsang, Alan Cheng Hou; Pak, On Shun

2018-03-01

The transport of active and passive particles plays central roles in diverse biological phenomena and engineering applications. In this paper, we present a theoretical investigation of a system consisting of an active particle and a passive particle in a confined micro-fluidic flow. The introduction of an external flow is found to induce the capture of the passive particle by the active particle via long-range hydrodynamic interactions among the particles. This hydrodynamic capture mechanism relies on an attracting stable equilibrium configuration formed by the particles, which occurs when the external flow intensity exceeds a certain threshold. We evaluate this threshold by studying the stability of the equilibrium configurations analytically and numerically. Furthermore, we study the dynamics of typical capture and non-capture events and characterize the basins of attraction of the equilibrium configurations. Our findings reveal a critical dependence of the hydrodynamic capture mechanism on the external flow intensity. Through adjusting the external flow intensity across the stability threshold, we demonstrate that the active particle can capture and release the passive particle in a controllable manner. Such a capture-and-release mechanism is desirable for biomedical applications such as the capture and release of therapeutic payloads by synthetic micro-swimmers in targeted drug delivery.
49 CFR 238.5 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... approach to the design of rail passenger equipment which controls the dissipation of energy during a... engineer attentiveness by monitoring select locomotive engineer-induced control activities. If fluctuation of a monitored locomotive engineer-induced control activity is not detected within a predetermined...
49 CFR 238.5 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... approach to the design of rail passenger equipment which controls the dissipation of energy during a... engineer attentiveness by monitoring select locomotive engineer-induced control activities. If fluctuation of a monitored locomotive engineer-induced control activity is not detected within a predetermined...
78 FR 32474 - Agency Information Collection Activities: Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-30

...; Programs to strengthen scientific and engineering research potential; Science and engineering education... support applied research was added to the Organic Act. In 1980, The Science and Engineering Equal... NATIONAL SCIENCE FOUNDATION Agency Information Collection Activities: Comment Request AGENCY...
77 FR 31401 - Agency Information Collection Activities: Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-25

...; Programs to strengthen scientific and engineering research potential; Science and engineering education... support applied research was added to the Organic Act. In 1980, The Science and Engineering Equal... NATIONAL SCIENCE FOUNDATION Agency Information Collection Activities: Comment Request AGENCY...
Production of L-carnitine by secondary metabolism of bacteria

PubMed Central

Bernal, Vicente; Sevilla, Ángel; Cánovas, Manuel; Iborra, José L

2007-01-01

The increasing commercial demand for L-carnitine has led to a multiplication of efforts to improve its production with bacteria. The use of different cell environments, such as growing, resting, permeabilized, dried, osmotically stressed, freely suspended and immobilized cells, to maintain enzymes sufficiently active for L-carnitine production is discussed in the text. The different cell states of enterobacteria, such as Escherichia coli and Proteus sp., which can be used to produce L-carnitine from crotonobetaine or D-carnitine as substrate, are analyzed. Moreover, the combined application of both bioprocess and metabolic engineering has allowed a deeper understanding of the main factors controlling the production process, such as energy depletion and the alteration of the acetyl-CoA/CoA ratio which are coupled to the end of the biotransformation. Furthermore, the profiles of key central metabolic activities such as the TCA cycle, the glyoxylate shunt and the acetate metabolism are seen to be closely interrelated and affect the biotransformation efficiency. Although genetically modified strains have been obtained, new strain improvement strategies are still needed, especially in Escherichia coli as a model organism for molecular biology studies. This review aims to summarize and update the state of the art in L-carnitine production using E. coli and Proteus sp, emphasizing the importance of proper reactor design and operation strategies, together with metabolic engineering aspects and the need for feed-back between wet and in silico work to optimize this biotransformation. PMID:17910757

X-33/RLV Program Aerospike Engines

NASA Technical Reports Server (NTRS)

1999-01-01

Substantial progress was made during the past year in support of the X-33/RLV program. X-33 activity was directed towards completing the remaining design work and building hardware to support test activities. RLV work focused on the nozzle ramp and powerpack technology tasks and on supporting vehicle configuration studies. On X-33, the design activity was completed to the detail level and the remainder of the drawings were released. Component fabrication and engine assembly activity was initiated, and the first two powerpacks and the GSE and STE needed to support powerpack testing were completed. Components fabrication is on track to support the first engine assembly schedule. Testing activity included powerpack testing and component development tests consisting of thrust cell single cell testing, CWI system spider testing, and EMA valve flow and vibration testing. Work performed for RLV was divided between engine system and technology development tasks. Engine system activity focused on developing the engine system configuration and supporting vehicle configuration studies. Also, engine requirements were developed, and engine performance analyses were conducted. In addition, processes were developed for implementing reliability, mass properties, and cost controls during design. Technology development efforts were divided between powerpack and nozzle ramp technology tasks. Powerpack technology activities were directed towards the development of a prototype powerpack and a ceramic turbine technology demonstrator (CTTD) test article which will allow testing of ceramic turbines and a close-coupled gas generator design. Nozzle technology efforts were focused on the selection of a composite nozzle supplier and on the fabrication and test of composite nozzle coupons.
Reverse engineering and identification in systems biology: strategies, perspectives and challenges

PubMed Central

Villaverde, Alejandro F.; Banga, Julio R.

2014-01-01

The interplay of mathematical modelling with experiments is one of the central elements in systems biology. The aim of reverse engineering is to infer, analyse and understand, through this interplay, the functional and regulatory mechanisms of biological systems. Reverse engineering is not exclusive of systems biology and has been studied in different areas, such as inverse problem theory, machine learning, nonlinear physics, (bio)chemical kinetics, control theory and optimization, among others. However, it seems that many of these areas have been relatively closed to outsiders. In this contribution, we aim to compare and highlight the different perspectives and contributions from these fields, with emphasis on two key questions: (i) why are reverse engineering problems so hard to solve, and (ii) what methods are available for the particular problems arising from systems biology? PMID:24307566
7th Annual Systems Biology Symposium: Systems Biology and Engineering

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

Galitski, Timothy P.

2008-04-01

Systems biology recognizes the complex multi-scale organization of biological systems, from molecules to ecosystems. The International Symposium on Systems Biology has been hosted by the Institute for Systems Biology in Seattle, Washington, since 2002. The annual two-day event gathers the most influential researchers transforming biology into an integrative discipline investingating complex systems. Engineering and application of new technology is a central element of systems biology. Genome-scale, or very small-scale, biological questions drive the enigneering of new technologies, which enable new modes of experimentation and computational analysis, leading to new biological insights and questions. Concepts and analytical methods in engineering aremore » now finding direct applications in biology. Therefore, the 2008 Symposium, funded in partnership with the Department of Energy, featured global leaders in "Systems Biology and Engineering."« less
Turbine nozzle positioning system

DOEpatents

Norton, Paul F.; Shaffer, James E.

1996-01-30

A nozzle guide vane assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and being attached to conventional metallic components. The nozzle guide vane assembly includes an outer shroud having a mounting leg with an opening defined therein, a tip shoe ring having a mounting member with an opening defined therein, a nozzle support ring having a plurality of holes therein and a pin positioned in the corresponding opening in the outer shroud, opening in the tip shoe ring and the hole in the nozzle support ring. A rolling joint is provided between metallic components of the gas turbine engine and the nozzle guide vane assembly. The nozzle guide vane assembly is positioned radially about a central axis of the gas turbine engine and axially aligned with a combustor of the gas turbine engine.
Turbine nozzle positioning system

DOEpatents

Norton, P.F.; Shaffer, J.E.

1996-01-30

A nozzle guide vane assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and being attached to conventional metallic components. The nozzle guide vane assembly includes an outer shroud having a mounting leg with an opening defined therein, a tip shoe ring having a mounting member with an opening defined therein, a nozzle support ring having a plurality of holes therein and a pin positioned in the corresponding opening in the outer shroud, opening in the tip shoe ring and the hole in the nozzle support ring. A rolling joint is provided between metallic components of the gas turbine engine and the nozzle guide vane assembly. The nozzle guide vane assembly is positioned radially about a central axis of the gas turbine engine and axially aligned with a combustor of the gas turbine engine. 9 figs.
Plasma physics of extreme astrophysical environments.

PubMed

Uzdensky, Dmitri A; Rightley, Shane

2014-03-01

Among the incredibly diverse variety of astrophysical objects, there are some that are characterized by very extreme physical conditions not encountered anywhere else in the Universe. Of special interest are ultra-magnetized systems that possess magnetic fields exceeding the critical quantum field of about 44 TG. There are basically only two classes of such objects: magnetars, whose magnetic activity is manifested, e.g., via their very short but intense gamma-ray flares, and central engines of supernovae (SNe) and gamma-ray bursts (GRBs)--the most powerful explosions in the modern Universe. Figuring out how these complex systems work necessarily requires understanding various plasma processes, both small-scale kinetic and large-scale magnetohydrodynamic (MHD), that govern their behavior. However, the presence of an ultra-strong magnetic field modifies the underlying basic physics to such a great extent that relying on conventional, classical plasma physics is often not justified. Instead, plasma-physical problems relevant to these extreme astrophysical environments call for constructing relativistic quantum plasma (RQP) physics based on quantum electrodynamics (QED). In this review, after briefly describing the astrophysical systems of interest and identifying some of the key plasma-physical problems important to them, we survey the recent progress in the development of such a theory. We first discuss the ways in which the presence of a super-critical field modifies the properties of vacuum and matter and then outline the basic theoretical framework for describing both non-relativistic and RQPs. We then turn to some specific astrophysical applications of relativistic QED plasma physics relevant to magnetar magnetospheres and to central engines of core-collapse SNe and long GRBs. Specifically, we discuss the propagation of light through a magnetar magnetosphere; large-scale MHD processes driving magnetar activity and responsible for jet launching and propagation in GRBs; energy-transport processes governing the thermodynamics of extreme plasma environments; micro-scale kinetic plasma processes important in the interaction of intense electric currents flowing through a magnetar magnetosphere with the neutron star surface; and magnetic reconnection of ultra-strong magnetic fields. Finally, we point out that future progress in applying RQP physics to real astrophysical problems will require the development of suitable numerical modeling capabilities.
Increasing brain angiotensin converting enzyme 2 activity decreases anxiety-like behavior in male mice by activating central Mas receptors

PubMed Central

Wang, Lei; de Kloet, Annette D.; Pati, Dipanwita; Hiller, Helmut; Smith, Justin A.; Pioquinto, David J.; Ludin, Jacob A.; Oh, S. Paul; Katovich, Michael J.; Frazier, Charles J.; Raizada, Mohan K.; Krause, Eric G.

2016-01-01

Over-activation of brain renin-angiotensin system (RAS) has been implicated in the etiology of anxiety disorders. Angiotensin converting enzyme (ACE2) inhibits RAS activity by converting angiotensin II, the effector peptide of RAS, to angiotensin-(1-7), which activates Mas receptors (MasR). Whether increasing brain ACE2 activity reduces anxiety by stimulating central MasR is unknown. To test the hypothesis that increasing brain ACE2 activity reduces anxiety-like behavior via central MasR stimulation, we generated male mice overexpressing ACE2 (ACE2 KI mice) and wild type littermate controls (WT). ACE2 KI mice explored the open arms of the elevated plus maze (EPM) significantly more than WT, suggesting increasing ACE2 activity is anxiolytic. Central delivery of diminazene aceturate, an ACE2 activator, to C57BL/6 mice also reduced anxiety-like behavior in the EPM, but centrally administering ACE2 KI mice A-779, a MasR antagonist, abolished their anxiolytic phenotype, suggesting that ACE2 reduces anxiety-like behavior by activating central MasR. To identify the brain circuits mediating these effects, we measured Fos, a marker of neuronal activation, subsequent to EPM exposure and found that ACE2 KI mice had decreased Fos in the bed nucleus of stria terminalis but had increased Fos in the basolateral amygdala (BLA). Within the BLA, we determined that ~62% of GABAergic neurons contained MasR mRNA and expression of MasR mRNA was upregulated by ACE2 overexpression, suggesting that ACE2 may influence GABA neurotransmission within the BLA via MasR activation. Indeed, ACE2 overexpression was associated with increased frequency of spontaneous inhibitory postsynaptic currents (indicative of presynaptic release of GABA) onto BLA pyramidal neurons and central infusion of A-779 eliminated this effect. Collectively, these results suggest that ACE2 may reduce anxiety-like behavior by activating central MasR that facilitate GABA release onto pyramidal neurons within the BLA. PMID:26767952
5. View toward the northeast at the inside elevation of ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. View toward the northeast at the inside elevation of the eastern segment of the north roundhouse. Bay numbers for stalls 58 through 66 are evident. - Central Railroad of New Jersey, Engine Terminal, Jersey City, Hudson County, NJ
ATMOSPHERIC RELEASES OF HEXAVALENT CHROMIUM FROM HARD CHROMIUM PLATING OPERATIONS

EPA Science Inventory

The University of Central Florida Department of Civil and Environmental Engineering is investigating methods for improved estimation of chemical releases which require reporting under provisions of SARA Title III (Toxic Release Inventory, Form R). This paper describes results fr...
Integrating Engineering Data Systems for NASA Spaceflight Projects

NASA Technical Reports Server (NTRS)

Carvalho, Robert E.; Tollinger, Irene; Bell, David G.; Berrios, Daniel C.

2012-01-01

NASA has a large range of custom-built and commercial data systems to support spaceflight programs. Some of the systems are re-used by many programs and projects over time. Management and systems engineering processes require integration of data across many of these systems, a difficult problem given the widely diverse nature of system interfaces and data models. This paper describes an ongoing project to use a central data model with a web services architecture to support the integration and access of linked data across engineering functions for multiple NASA programs. The work involves the implementation of a web service-based middleware system called Data Aggregator to bring together data from a variety of systems to support space exploration. Data Aggregator includes a central data model registry for storing and managing links between the data in disparate systems. Initially developed for NASA's Constellation Program needs, Data Aggregator is currently being repurposed to support the International Space Station Program and new NASA projects with processes that involve significant aggregating and linking of data. This change in user needs led to development of a more streamlined data model registry for Data Aggregator in order to simplify adding new project application data as well as standardization of the Data Aggregator query syntax to facilitate cross-application querying by client applications. This paper documents the approach from a set of stand-alone engineering systems from which data are manually retrieved and integrated, to a web of engineering data systems from which the latest data are automatically retrieved and more quickly and accurately integrated. This paper includes the lessons learned through these efforts, including the design and development of a service-oriented architecture and the evolution of the data model registry approaches as the effort continues to evolve and adapt to support multiple NASA programs and priorities.
Characterizing Interdisciplinarity of Researchers and Research Topics Using Web Search Engines

PubMed Central

Sayama, Hiroki; Akaishi, Jin

2012-01-01

Researchers' networks have been subject to active modeling and analysis. Earlier literature mostly focused on citation or co-authorship networks reconstructed from annotated scientific publication databases, which have several limitations. Recently, general-purpose web search engines have also been utilized to collect information about social networks. Here we reconstructed, using web search engines, a network representing the relatedness of researchers to their peers as well as to various research topics. Relatedness between researchers and research topics was characterized by visibility boost—increase of a researcher's visibility by focusing on a particular topic. It was observed that researchers who had high visibility boosts by the same research topic tended to be close to each other in their network. We calculated correlations between visibility boosts by research topics and researchers' interdisciplinarity at the individual level (diversity of topics related to the researcher) and at the social level (his/her centrality in the researchers' network). We found that visibility boosts by certain research topics were positively correlated with researchers' individual-level interdisciplinarity despite their negative correlations with the general popularity of researchers. It was also found that visibility boosts by network-related topics had positive correlations with researchers' social-level interdisciplinarity. Research topics' correlations with researchers' individual- and social-level interdisciplinarities were found to be nearly independent from each other. These findings suggest that the notion of “interdisciplinarity" of a researcher should be understood as a multi-dimensional concept that should be evaluated using multiple assessment means. PMID:22719935
Characterizing interdisciplinarity of researchers and research topics using web search engines.

PubMed

Sayama, Hiroki; Akaishi, Jin

2012-01-01

Researchers' networks have been subject to active modeling and analysis. Earlier literature mostly focused on citation or co-authorship networks reconstructed from annotated scientific publication databases, which have several limitations. Recently, general-purpose web search engines have also been utilized to collect information about social networks. Here we reconstructed, using web search engines, a network representing the relatedness of researchers to their peers as well as to various research topics. Relatedness between researchers and research topics was characterized by visibility boost-increase of a researcher's visibility by focusing on a particular topic. It was observed that researchers who had high visibility boosts by the same research topic tended to be close to each other in their network. We calculated correlations between visibility boosts by research topics and researchers' interdisciplinarity at the individual level (diversity of topics related to the researcher) and at the social level (his/her centrality in the researchers' network). We found that visibility boosts by certain research topics were positively correlated with researchers' individual-level interdisciplinarity despite their negative correlations with the general popularity of researchers. It was also found that visibility boosts by network-related topics had positive correlations with researchers' social-level interdisciplinarity. Research topics' correlations with researchers' individual- and social-level interdisciplinarities were found to be nearly independent from each other. These findings suggest that the notion of "interdisciplinarity" of a researcher should be understood as a multi-dimensional concept that should be evaluated using multiple assessment means.
Shaping the Future Landscape: Catchment Systems Engineering and the Decision Support Matrix Approach

NASA Astrophysics Data System (ADS)

Hewett, Caspar; Quinn, Paul; Wilkinson, Mark; Wainwright, John

2017-04-01

Land degradation is widely recognised as one of the great environmental challenges facing humanity today, much of which is directly associated with human activity. The negative impacts of climate change and of the way in which we have engineered the landscape through, for example, agriculture intensification and deforestation, need to be addressed. However, the answer is not a simple matter of doing the opposite of current practice. Nor is non-intervention a viable option. There is a need to bring together approaches from the natural and social sciences both to understand the issues and to act to solve real problems. We propose combining a Catchment Systems Engineering (CSE) approach that builds on existing approaches such as Natural Water Retention Measures, Green infrastructure and Nature-Based Solutions with a multi-scale framework for decision support that has been successfully applied to diffuse pollution and flood risk management. The CSE philosophy follows that of Earth Systems Engineering and Management, which aims to engineer and manage complex coupled human-natural systems in a highly integrated, rational manner. CSE is multi-disciplinary, and necessarily involves a wide range of subject areas including anthropology, engineering, environmental science, ethics and philosophy. It offers a rational approach which accepts the fact that we need to engineer and act to improve the functioning of the existing catchment entity on which we rely. The decision support framework proposed draws on physical and mathematical modelling; Participatory Action Research; and demonstration sites at which practical interventions are implemented. It is predicated on the need to work with stakeholders to co-produce knowledge that leads to proactive interventions to reverse the land degradation we observe today while sustaining the agriculture humanity needs. The philosophy behind CSE and examples of where it has been applied successfully are presented. The Decision Support Matrix (DSM) approach is introduced as a way to engage stakeholders at all scales, helping to inform decision making and motivate intervention. Two existing visualization and communication tools produced using the DSM approach are discussed: The FARM (Floods and Agriculture Risk Matrix) and CAVERTI (Communication And Visualizing Erosion-associated Risks to Infrastructure). Such tools can play a central role in encouraging a more holistic engineering approach to managing catchment system function that combines food production with a reversal of land degradation, providing a 'win-win' situation for all.
Mission Evaluation Room Intelligent Diagnostic and Analysis System (MIDAS)

NASA Technical Reports Server (NTRS)

Pack, Ginger L.; Falgout, Jane; Barcio, Joseph; Shnurer, Steve; Wadsworth, David; Flores, Louis

1994-01-01

The role of Mission Evaluation Room (MER) engineers is to provide engineering support during Space Shuttle missions, for Space Shuttle systems. These engineers are concerned with ensuring that the systems for which they are responsible function reliably, and as intended. The MER is a central facility from which engineers may work, in fulfilling this obligation. Engineers participate in real-time monitoring of shuttle telemetry data and provide a variety of analyses associated with the operation of the shuttle. The Johnson Space Center's Automation and Robotics Division is working to transfer advances in intelligent systems technology to NASA's operational environment. Specifically, the MER Intelligent Diagnostic and Analysis System (MIDAS) project provides MER engineers with software to assist them with monitoring, filtering and analyzing Shuttle telemetry data, during and after Shuttle missions. MIDAS off-loads to computers and software, the tasks of data gathering, filtering, and analysis, and provides the engineers with information which is in a more concise and usable form needed to support decision making and engineering evaluation. Engineers are then able to concentrate on more difficult problems as they arise. This paper describes some, but not all of the applications that have been developed for MER engineers, under the MIDAS Project. The sampling described herewith was selected to show the range of tasks that engineers must perform for mission support, and to show the various levels of automation that have been applied to assist their efforts.
Genetic Engineering of Algae for Enhanced Biofuel Production ▿

PubMed Central

Radakovits, Randor; Jinkerson, Robert E.; Darzins, Al; Posewitz, Matthew C.

2010-01-01

There are currently intensive global research efforts aimed at increasing and modifying the accumulation of lipids, alcohols, hydrocarbons, polysaccharides, and other energy storage compounds in photosynthetic organisms, yeast, and bacteria through genetic engineering. Many improvements have been realized, including increased lipid and carbohydrate production, improved H2 yields, and the diversion of central metabolic intermediates into fungible biofuels. Photosynthetic microorganisms are attracting considerable interest within these efforts due to their relatively high photosynthetic conversion efficiencies, diverse metabolic capabilities, superior growth rates, and ability to store or secrete energy-rich hydrocarbons. Relative to cyanobacteria, eukaryotic microalgae possess several unique metabolic attributes of relevance to biofuel production, including the accumulation of significant quantities of triacylglycerol; the synthesis of storage starch (amylopectin and amylose), which is similar to that found in higher plants; and the ability to efficiently couple photosynthetic electron transport to H2 production. Although the application of genetic engineering to improve energy production phenotypes in eukaryotic microalgae is in its infancy, significant advances in the development of genetic manipulation tools have recently been achieved with microalgal model systems and are being used to manipulate central carbon metabolism in these organisms. It is likely that many of these advances can be extended to industrially relevant organisms. This review is focused on potential avenues of genetic engineering that may be undertaken in order to improve microalgae as a biofuel platform for the production of biohydrogen, starch-derived alcohols, diesel fuel surrogates, and/or alkanes. PMID:20139239
Carburetor for internal combustion engines

DOEpatents

Csonka, John J.; Csonka, Albert B.

1978-01-01

A carburetor for internal combustion engines having a housing including a generally discoidal wall and a hub extending axially from the central portion thereof, an air valve having a relatively flat radially extending surface directed toward and concentric with said discoidal wall and with a central conoidal portion having its apex directed toward the interior of said hub portion. The housing wall and the radially extending surface of the valve define an air passage converging radially inwardly to form an annular valving construction and thence diverge into the interior of said hub. The hub includes an annular fuel passage terminating at its upper end in a circumferential series of micro-passages for directing liquid fuel uniformly distributed into said air passage substantially at said valving constriction at right angles to the direction of air flow. The air valve is adjustable axially toward and away from the discoidal wall of the carburetor housing to regulate the volume of air drawn into the engine with which said carburetor is associated. Fuel is delivered under pressure to the fuel metering valve and from there through said micro-passages and controlled cams simultaneously regulate the axial adjustment of said air valve and the rate of delivery of fuel through said micro-passages according to a predetermined ratio pattern. A third jointly controlled cam simultaneously regulates the ignition timing in accordance with various air and fuel supply settings. The air valve, fuel supply and ignition timing settings are all independent of the existing degree of engine vacuum.
The role of the host in a cooperating mainframe and workstation environment, volumes 1 and 2

NASA Technical Reports Server (NTRS)

Kusmanoff, Antone; Martin, Nancy L.

1989-01-01

In recent years, advancements made in computer systems have prompted a move from centralized computing based on timesharing a large mainframe computer to distributed computing based on a connected set of engineering workstations. A major factor in this advancement is the increased performance and lower cost of engineering workstations. The shift to distributed computing from centralized computing has led to challenges associated with the residency of application programs within the system. In a combined system of multiple engineering workstations attached to a mainframe host, the question arises as to how does a system designer assign applications between the larger mainframe host and the smaller, yet powerful, workstation. The concepts related to real time data processing are analyzed and systems are displayed which use a host mainframe and a number of engineering workstations interconnected by a local area network. In most cases, distributed systems can be classified as having a single function or multiple functions and as executing programs in real time or nonreal time. In a system of multiple computers, the degree of autonomy of the computers is important; a system with one master control computer generally differs in reliability, performance, and complexity from a system in which all computers share the control. This research is concerned with generating general criteria principles for software residency decisions (host or workstation) for a diverse yet coupled group of users (the clustered workstations) which may need the use of a shared resource (the mainframe) to perform their functions.
Minocycline encapsulated chitosan nanoparticles for central antinociceptive activity.

PubMed

Nagpal, Kalpana; Singh, S K; Mishra, D N

2015-01-01

The purpose of the study is to explore the central anti-nociceptive activity of brain targeted nanoparticles (NP) of minocycline hydrochloride (MH). The NP were formulated using the modified ionotropic gelation method (MHNP) and were coated with Tween 80 (T80) to target them to brain (cMHNP). The formulated nanoparticles have already been characterized for particle size, zeta potential, drug entrapment efficiency and in vitro drug release. The nanoparticles were then evaluated for pharmacodynamic activity using thermal methods. The pure drug and the formulation, MHNP were not able to show a statistically significant central analgesic activity. cMHNP on the other hand evidenced a significant central analgesic activity. Animal models evidenced that brain targeted nanoparticles may be utilized for effective delivery of central anti-nociceptive effect of MH. Further clinical studies are required to explore the activity for mankind. Copyright © 2014 Elsevier B.V. All rights reserved.
Paired Peer Learning through Engineering Education Outreach

ERIC Educational Resources Information Center

Fogg-Rogers, Laura; Lewis, Fay; Edmonds, Juliet

2017-01-01

Undergraduate education incorporating active learning and vicarious experience through education outreach presents a critical opportunity to influence future engineering teaching and practice capabilities. Engineering education outreach activities have been shown to have multiple benefits; increasing interest and engagement with science and…
Scale-Up Information for Gas-Phase Ammonia Treatment of Uranium in the Vadose Zone at the Hanford Site Central Plateau

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

Truex, Michael J.; Szecsody, James E.; Zhong, Lirong

Uranium is present in the vadose zone at the Hanford Central Plateau and is of concern for protection of groundwater. The Deep Vadose Zone Treatability Test Plan for the Hanford Central Plateau identified gas-phase treatment and geochemical manipulation as potentially effective treatment approaches for uranium and technetium in the Hanford Central Plateau vadose zone. Based on laboratory evaluation, use of ammonia vapor was selected as the most promising uranium treatment candidate for further development and field testing. While laboratory tests have shown that ammonia treatment effectively reduces the mobility of uranium, additional information is needed to enable deployment of thismore » technology for remediation. Of importance for field applications are aspects of the technology associated with effective distribution of ammonia to a targeted treatment zone, understanding the fate of injected ammonia and its impact on subsurface conditions, and identifying effective monitoring approaches. In addition, information is needed to select equipment and operational parameters for a field design. As part of development efforts for the ammonia technology for remediation of vadose zone uranium contamination, field scale-up issues were identified and have been addressed through a series of laboratory and modeling efforts. This report presents a conceptual description for field application of the ammonia treatment process, engineering calculations to support treatment design, ammonia transport information, field application monitoring approaches, and a discussion of processes affecting the fate of ammonia in the subsurface. The report compiles this information from previous publications and from recent research and development activities. The intent of this report is to provide technical information about these scale-up elements to support the design and operation of a field test for the ammonia treatment technology.« less

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