Science.gov

Sample records for submetidas ao transporte

  1. Studies of the Canadian Arctic Archipelago water transport and its relationship to basin-local forcings: Results from AO-FVCOM

    NASA Astrophysics Data System (ADS)

    Zhang, Yu; Chen, Changsheng; Beardsley, Robert C.; Gao, Guoping; Lai, Zhigang; Curry, Beth; Lee, Craig M.; Lin, Huichan; Qi, Jianhua; Xu, Qichun

    2016-06-01

    A high-resolution (up to 2 km), unstructured-grid, fully coupled Arctic sea ice-ocean Finite-Volume Community Ocean Model (AO-FVCOM) was employed to simulate the flow and transport through the Canadian Arctic Archipelago (CAA) over the period 1978-2013. The model-simulated CAA outflow flux was in reasonable agreement with the flux estimated based on measurements across Davis Strait, Nares Strait, Lancaster Sound, and Jones Sounds. The model was capable of reproducing the observed interannual variability in Davis Strait and Lancaster Sound. The simulated CAA outflow transport was highly correlated with the along-strait and cross-strait sea surface height (SSH) difference. Compared with the wind forcing, the sea level pressure (SLP) played a dominant role in establishing the SSH difference and the correlation of the CAA outflow with the cross-strait SSH difference can be explained by a simple geostrophic balance. The change in the simulated CAA outflow transport through Davis Strait showed a negative correlation with the net flux through Fram Strait. This correlation was related to the variation of the spatial distribution and intensity of the slope current over the Beaufort Sea and Greenland shelves. The different basin-scale surface forcings can increase the model uncertainty in the CAA outflow flux up to 15%. The daily adjustment of the model elevation to the satellite-derived SSH in the North Atlantic region outside Fram Strait could produce a larger North Atlantic inflow through west Svalbard and weaken the outflow from the Arctic Ocean through east Greenland.

  2. The Uses of Research Sponsored by the Administration on Aging (AoA). Case Study No. 1. Transportation Services for the Elderly. Executive Summary.

    ERIC Educational Resources Information Center

    Yin, Robert K.; Heinsohn, Ingrid

    This case study, one in a series of research efforts designed to examine the utilization of the Administration on Aging's research, describes the different types of uses of materials produced by a research project on improvement of transportation services for the elderly. (The materials are a state-of-the-art report, planning handbook, and…

  3. Retinal AO OCT

    NASA Astrophysics Data System (ADS)

    Zawadzki, Robert J.; Miller, Donald T.

    The last two decades have witnessed extraordinary advances in optical technology to image noninvasively and at high resolution the posterior segment of the eye. Two of the most impactful technological advancements over this period have arguably been optical coherence tomography (OCT) and adaptive optics (AO). The strengths of these technologies complement each other and when combined have been shown to provide unprecedented, micron-scale resolution (<3 μm) in all three dimensions and sensitivity to image the cellular retina in the living eye. This powerful extension of OCT, that is AO-OCT, is the focus of this chapter. It presents key aspects of designing and implementing AO-OCT systems. Particular attention is devoted to the relevant optical properties of the eye that ultimately define these systems, AO componentry and operation tailored for ophthalmic use, and of course use of the latest technologies and methods in OCT for ocular imaging. It surveys the wide range of AO-OCT designs that have been developed for retinal imaging, with AO integrated into every major OCT design configuration. Finally, it reviews the scientific and clinical studies reported to date that show the exciting potential of AO-OCT to image the microscopic retina and fundus in ways not previously possible with other noninvasive methods and a look to future developments in this rapidly growing field.

  4. TRANSPORT

    EPA Science Inventory

    Presentation outline: transport principles, effective solubility; gasoline composition; and field examples (plume diving).
    Presentation conclusions: MTBE transport follows from - phyiscal and chemical properties and hydrology. Field examples show: MTBE plumes > benzene plu...

  5. AO Group Annual Report

    SciTech Connect

    Olivier, S

    2005-10-04

    The Adaptive Optics (AO) Group in I Division develops and tests a broad range of advanced wavefront control technologies. Current applications focus on: Remote sensing, High power lasers, Astronomy, and Human vision. In the area of remote sensing, the AO Group leads a collaborative effort with LLNL's Nonproliferation, Arms Control & International Security (NAI) Directorate on Enhanced Surveillance Imaging. The ability to detect and identify individual people or vehicles from long-range is an important requirement for proliferation detection and homeland security. High-resolution imaging along horizontal paths through the atmosphere is limited by turbulence, which blurs and distorts the image. For ranges over {approx}one km, visible image resolution can be reduced by over an order of magnitude. We have developed an approach based on speckle imaging that can correct the turbulence-induced blurring and provide high resolution imagery. The system records a series of short exposure images which freeze the atmospheric effects. We can then estimate the image magnitude and phase using a bispectral estimation algorithm which cancels the atmospheric effects while maintaining object information at the diffraction limit of the imaging system.

  6. Transportation

    NASA Technical Reports Server (NTRS)

    Vontiesenhausen, G.

    1986-01-01

    A summary of tether transportation is given. Four steps were used over a period of time. First, theoretical engineering feasibility and technology requirements were determined. Then the survivors of that effort went into step two in the analysis of promising candidates. Those survivors went into the third phase which is engineering design and cost benefits. Survivors entered into the demonstration mission definition phase. Transportation studies have covered two kinds of deployments. First, steady state deployment was studied. Like the TSS, it's nearly vertical. It takes a long time to deploy and involves relatively high tether tension. Secondly, dynamic deployment was studied. Deployment started in an almost horizontal direction under a very shallow angle which allows a high deployment rate under very low tension. Momentum transfer here occurs by libration. Specific payloads were used to study tethered transportation benefits. Four transportation concepts were studied with regard to cost benefits. A tethered orbiter deboost from the space station, an OTV boost up from the Space Station, a science platform on a tether with a possible micro-g lab moving in between platform and station, and a tethered boost of payloads fromthe orbiter are the four concepts. These benefits are examined in detail.

  7. Transportability

    DTIC Science & Technology

    2013-04-25

    psi). (g) Maximum axle load (pneumatic tires) - 2,268 kg (5,000 lb). (h) Maximum wheel load (pneumatic tires) - 1,134 kg (2,500 lb). (i...survivability following the shock or vibration environment induced. Vehicles not typically transported with payload such as wreckers, truck tractors ...combination weight rating (GCWR) means the value specified by the manufacturer as the loaded weight of the combination vehicle. (d) Gross axle weight

  8. Transportation

    DTIC Science & Technology

    2007-01-01

    International (cont.) European Commission – Directorate General for Energy and Transport, Brussels, Belgium Headquarters Netherlands Customs ...100,000 by 2014. As a result of these challenges and due to the increase in intermodal freight traffic, a customer /client relationship has...increase by 50% domestically and 110% internationally by 2016 (CRS, 2007). United Parcel Service (UPS), FedEx, and DHL currently control the package

  9. MEMS AO for Planet Finding

    NASA Technical Reports Server (NTRS)

    Rao, Shanti; Wallace, J. Kent; Shao, Mike; Schmidtlin, Edouard; Levine, B. Martin; Samuele, Rocco; Lane, Benjamin; Chakrabarti, Supriya; Cook, Timothy; Hicks, Brian; hide

    2008-01-01

    This slide presentation reviews a method for planet finding using microelectromechanical systems (MEMS) Adaptive Optics (AO). The use of a deformable mirror (DM) is described as a part of the instrument that was designed with a nulling interferometer. The strategy that is used is described in detail.

  10. Cometas: Das Lendas aos Fatos

    NASA Astrophysics Data System (ADS)

    Voelzke, M. R.

    O descobrimento de cometas, devido ao seu aparecimento espetacular, tem registro nas mais antigas culturas humanas. A primeira referência situa-se no ano de 1095 antes de Cristo [a.C.; HO; HO, 1962]. A quantidade de registros de descobrimentos cometários, principalmente provenientes do território chinês em particular e do oriente em geral, aumentou gradualmente a partir do quarto século depois de Cristo (d.C.). É de origem chinesa a primeira referência ao cometa P/Halley no ano de 240 a.C. [VOELZKE, 1993]. Com o desenvolvimento da astronomia relativamente às técnicas observacionais os descobrimentos bem como as observações cometárias aumentaram sensivelmente a partir do século XVII, sendo que a partir do século XIX um novo incremento ocorreu devido ao emprego da fotografia e a resultante melhora de sensibilidade na observação.

  11. Aerosol Observing System (AOS) Handbook

    SciTech Connect

    Jefferson, A

    2011-01-17

    The Aerosol Observing System (AOS) is a suite of in situ surface measurements of aerosol optical and cloud-forming properties. The instruments measure aerosol properties that influence the earth’s radiative balance. The primary optical measurements are those of the aerosol scattering and absorption coefficients as a function of particle size and radiation wavelength and cloud condensation nuclei (CCN) measurements as a function of percent supersaturation. Additional measurements include those of the particle number concentration and scattering hygroscopic growth. Aerosol optical measurements are useful for calculating parameters used in radiative forcing calculations such as the aerosol single-scattering albedo, asymmetry parameter, mass scattering efficiency, and hygroscopic growth. CCN measurements are important in cloud microphysical models to predict droplet formation.

  12. SRAO: the first southern robotic AO system

    NASA Astrophysics Data System (ADS)

    Law, Nicholas M.; Ziegler, Carl; Tokovinin, Andrei

    2016-08-01

    We present plans for SRAO, the first Southern Robotic AO system. SRAO will use AO-assisted speckle imaging and Robo-AO-heritage high efficiency observing to confirm and characterize thousands of planet candidates produced by major new transit surveys like TESS, and is the first AO system to be capable of building a comprehensive several-thousand-target multiplicity survey at sub-AU scales across the main sequence. We will also describe results from Robo-AO, the first robotic LGS-AO system. Robo-AO has observed tens of thousands of Northern targets, often using a similar speckle or Lucky-Imaging assisted mode. SRAO will be a moderate-order natural-guide-star adaptive optics system which uses an innovative photoncounting wavefront sensor and EMCCD speckle-imaging camera to guide on faint stars with the 4.1m SOAR telescope. The system will produce diffraction-limited imaging in the NIR on targets as faint as mν = 16. In AO-assisted speckle imaging mode the system will attain the 30-mas visible diffraction limit on targets at least as faint as mν = 17. The system will be the first Southern hemisphere robotic adaptive optics system, with overheads an order of magnitude smaller than comparable systems. Using Robo-AO's proven robotic AO software, SRAO will be capable of observing overheads on sub-minute scales, allowing the observation of at least 200 targets per night. SRAO will attain three times the angular resolution of the Palomar Robo-AO system in the visible.

  13. MagAO: status and science

    NASA Astrophysics Data System (ADS)

    Morzinski, Katie M.; Close, Laird M.; Males, Jared R.; Hinz, Phil M.; Esposito, Simone; Riccardi, Armando; Briguglio, Runa; Follette, Katherine B.; Pinna, Enrico; Puglisi, Alfio; Vezilj, Jennifer; Xompero, Marco; Wu, Ya-Lin

    2016-07-01

    "MagAO" is the adaptive optics instrument at the Magellan Clay telescope at Las Campanas Observatory, Chile. MagAO has a 585-actuator adaptive secondary mirror and 1000-Hz pyramid wavefront sensor, operating on natural guide stars from R-magnitudes of -1 to 15. MagAO has been in on-sky operation for 166 nights since installation in 2012. MagAO's unique capabilities are simultaneous imaging in the visible and infrared with VisAO and Clio, excellent performance at an excellent site, and a lean operations model. Science results from MagAO include the first ground-based CCD image of an exoplanet, demonstration of the first accreting protoplanets, discovery of a new wide-orbit exoplanet, and the first empirical bolometric luminosity of an exoplanet. We describe the status, report the AO performance, and summarize the science results. New developments reported here include color corrections on red guide stars for the wavefront sensor; a new field stop stage to facilitate VisAO imaging of extended sources; and eyepiece observing at the visible-light diffraction limit of a 6.5-m telescope. We also discuss a recent hose failure that led to a glycol coolant leak, and the recovery of the adaptive secondary mirror (ASM) after this recent (Feb. 2016) incident.

  14. PSF reconstruction for AO photometry and astrometry

    NASA Astrophysics Data System (ADS)

    Ascenso, J.; Neichel, B.; Silva, M.; Fusco, T.; Garcia, P.

    2015-12-01

    Extracting accurate photometry (and astrometry) from images taken with adaptive optics assisted instruments is particularly challenging. Current post-processing tools are not prepared to achieve high accuracy from AO data, especially in limiting cases of crowded fields and marginally resolved sources. We quantify the limitations of these tools with synthetic images, and present a proof-of-concept study showing the potential of using reconstructed PSFs from the (GL)AO system telemetry to increase the measured photometric accuracy. We show that the photometric accuracy is significantly improved with a good PSF reconstruction in considerably crowded regions. We demonstrate the need for a dedicated post-processing tool that incorporates available information about the PSF, as well as the ability to adjust to the spatial variations of the PSF characteristic of AO data.

  15. Twelve thousand laser-AO observations: first results from the Robo-AO large surveys

    NASA Astrophysics Data System (ADS)

    Law, Nicholas M.; Baranec, Christoph; Riddle, Reed L.

    2014-07-01

    Robo-AO is the first AO system which can feasibly perform surveys of thousands of targets. The system has been operating in a fully robotic mode on the Palomar 1.5m telescope for almost two years. Robo-AO has completed nearly 12,000 high-angular-resolution observations in almost 20 separate science programs including exoplanet characterization, field star binarity, young star binarity and solar system observations. We summarize the Robo-AO surveys and the observations completed to date. We also describe the data-reduction pipeline we developed for Robo-AO—the first fully-automated AO data-reduction, point-spread-function subtraction and companion-search pipeline.

  16. Characterization of an AO-OCT system

    SciTech Connect

    Evans, J W; Zawadzki, R J; Jones, S; Olivier, S; Werner, J S

    2007-07-26

    Adaptive optics (AO) and optical coherence tomography (OCT) are powerful imaging modalities that, when combined, can provide high-volumetric-resolution, images of the retina. The AO-OCT system at UC Davis has been under development for 2 years and has demonstrated the utility of this technology for microscopic, volumetric, in vivo retinal imaging [1]. The current system uses an AOptix bimorph deformable mirror (DM) for low-order, high-stroke correction [2] and a 140-actuator Boston Micromachines DM for high-order correction [3]. We are beginning to investigate the potential for increasing the image contrast in this system using higher-order wavefront correction. The first step in this analysis is to quantify the residual wavefront error (WFE) in the current system. Developing an error budget is a common tool for improved performance and system design in astronomical AO systems [4, 5]. The process for vision science systems is also discussed in several texts e.g. [6], but results from this type of analysis have rarely been included in journal articles on AO for vision science. Careful characterization of the AO system will lead to improved performance and inform the design of a future high-contrast system. In general, an AO system error budget must include an analysis of three categories of residual WFE: errors in measuring the phase, errors caused by limitations of the DM(s), and errors introduced by temporal variation. Understanding the mechanisms and relative size of these errors is critical to improving system performance. In this paper we discuss the techniques for characterizing these error sources in the AO-OCT system. It is useful to first calculate an error budget for the simpler case using a model eye, and then add the additional errors introduced for the case of a human subject. Measurement error includes calibration error, wavefront sensor (WFS) CCD noise, and sampling errors. Calibration errors must be measured by an external system. Typically this

  17. AoB PLANTS: origins and features.

    PubMed

    Jackson, Michael B

    2009-01-01

    AoB PLANTS is a peer reviewed, Open Access (OA) journal owned and run by plant biologists and published by Oxford University Press. The journal publishes research papers, reviews and opinion papers on all aspects of land based plant biology. They are made available rapidly online and can be accessed without the need for subscriptions or payment. Several difficulties in conventional publishing of peer-reviewed manuscripts encouraged AoB PLANTS to adopt OA. Open Access helps sidestep library budgets which are struggling to purchase the increasing numbers of journals. Open Access makes research freely available both to the academic community and beyond while publishing online only eliminates the need to reject good manuscripts simply to control the size of the printed journal. Finally, the journal chose to go OA to ensure the widest possible international readership for the growing amount of high-quality plant science research being carried out worldwide in response to problems such as climate change and food shortages. Responses to a wide-ranging online questionnaire indicated strong international support for a journal such as AoB PLANTS. AoB PLANTS strives for fair and rapid peer review followed by fast publication of accepted papers. For an initial period, there will be no OA fees, and fees will remain modest once introduced. AoB PLANTS adopts double-blind peer review using published criteria for acceptability as a basis for decision-making. Accepted papers are published shortly after acceptance together with referees' analyses using Stanford University Libraries High Wire Press H2O platform. Authors retain ownership of the copyright in their papers.

  18. Recent enhancements to the NAOMI AO system

    NASA Astrophysics Data System (ADS)

    Jolley, Paul D.; Goodsell, Stephen; Benn, Chris R.; Gregory, Thomas; Rees, Simon; van der Hoeven, Michiel; Blanken, Maarten; Pit, Renee

    2004-10-01

    The Nasmyth Adaptive Optics Multipurpose Instrument (NAOMI) is the adaptive optics (AO) platform on the 4.2m William Herschel Telescope (WHT) at the Isaac Newton Group of Telescopes (ING). Until recently NAOMI has been concentrating on near infrared observations using the Isaac Newton Group Red Imaging Device (INGRID). Recent developments have added an extra optical port to NAOMI. The observer can now rapidly switch between infrared and optical instrumentation during AO observing, making the system more appealing for visiting instruments. To allow for the operation of the common user optical spectrograph OASIS, a new optical path was created around the existing NAOMI optics. Various mechanisms were also added to the whole optical system. The OASIS beam was reshaped to f/20. The original optical/IR beam remains unchanged at f/16, and forms a new universal science port (USP). The existing Nasmyth Calibration Unit (NCU) has been replaced with a new design. This new NCU has multiple fibre-fed light sources that include continuum and arc lamps. The intensity of light can be individually adjusted via computer control. A new acquisition camera is mounted such that it can be used simultaneously with the spectral lamps. Software upgrades now allow faster deformable mirror calibration. A moveable mirror is used to select which science port will receive the light. Enhancements to the NAOMI AO system are discussed in this paper and suggestions for possible future upgrades.

  19. MEMS DM development at Iris AO, Inc.

    NASA Astrophysics Data System (ADS)

    Helmbrecht, Michael A.; He, Min; Kempf, Carl J.; Besse, Marc

    2011-03-01

    Iris AO is actively developing piston-tip-tilt (PTT) segmented MEMS deformable mirrors (DM) and adaptive optics (AO) controllers for these DMs. This paper discusses ongoing research at Iris AO that has advanced the state-of-the-art of these devices and systems over the past year. Improvements made to open-loop operation and mirror fabrication enables mirrors to open-loop flatten to 4 nm rms. Additional testing of an anti snap-in technology was conducted and demonstrates that the technology can withstand 100 million snap-in events without failure. Deformable mirrors with dielectric coatings are shown that are capable of handling 630 W/cm2 of incident laser power. Over a localized region on the segment, the dielectric coatings can withstand 100kW/cm2 incident laser power for 30 minutes. Results from the first-ever batch of PTT489 DMs that were shipped to pilot customers are reported. Optimizations made to the open-loop PTT controller are shown to have latencies of 157.5 μs and synchronous array update rates of nearly 6.5 kHz. Finally, plans for the design and fabrication of the next-generation PTT939 DM are presented.

  20. Effects of adrenergic agents on the expression of zebrafish (Danio rerio) vitellogenin Ao1

    SciTech Connect

    Yin Naida; Jin Xia; He Jiangyan; Yin Zhan

    2009-07-01

    Teleost vitellogenins (VTGs) are large multidomain apolipoproteins, traditionally considered to be estrogen-responsive precursors of the major egg yolk proteins, expressed and synthesized mainly in hepatic tissue. The inducibility of VTGs has made them one of the most frequently used in vivo and in vitro biomarkers of exposure to estrogen-active substances. A significant level of zebrafish vtgAo1, a major estrogen responsive form, has been unexpectedly found in heart tissue in our present studies. Our studies on zebrafish cardiomyopathy, caused by adrenergic agonist treatment, suggest a similar protective function of the cardiac expressed vtgAo1. We hypothesize that its function is to unload surplus intracellular lipids in cardiomyocytes for 'reverse triglyceride transportation' similar to that found in lipid transport proteins in mammals. Our results also demonstrated that zebrafish vtgAo1 mRNA expression in heart can be suppressed by both {alpha}-adrenergic agonist, phenylephrine (PE) and {beta}-adrenergic agonist, isoproterenol (ISO). Furthermore, the strong stimulation of zebrafish vtgAo1 expression in plasma induced by the {beta}-adrenergic antagonist, MOXIsylyl, was detected by Enzyme-Linked ImmunoSorbent Assay (ELISA). Such stimulation cannot be suppressed by taMOXIfen, an antagonist to estrogen receptors. Thus, our present data indicate that the production of teleost VTG in vivo can be regulated not only by estrogenic agents, but by adrenergic signals as well.

  1. Deformable mirror designs for extreme AO (XAO)

    NASA Astrophysics Data System (ADS)

    Cavaco, Jeffrey; Wirth, Allan

    2014-08-01

    One of the science missions for the next generation of extremely large ground based telescopes (30-42m apertures) is the imaging and spectroscopy of exoplanets. To achieve that goal an Adaptive Optics (AO) subsystem with a very large number of corrected modes is required. To provide contrast ratios in the range of 10-9 or better for a 42m telescope an AO system with 25,000 to 60,000 channels will be needed. This is approximately an order of magnitude beyond the current state of the art. Adaptive Optics Associates Xinetics has developed the Photonex Module Deformable Mirror (DM) technology specifically to address the needs of extreme AO for high contrast applications. A Photonex Module is a monolithic block of electrostrictive ceramic in which a high density of individually addressable actuators are formed by screen printing of electrodes and partial wire saw cutting of the ceramic. The printed electrode structures also allow all electrical connections to be made at the back surface of the module via flex circuits. Actuator spacings of 1mm or less have been achieved using this approach. The individual modules can be edge butted and bonded to achieve high actuator count. The largest DMs fabricated to date have 4096 actuators in a 64X64mm array. In this paper the engineering challenges in extending this technology by a factor of ten or more in actuator count will be discussed. A conceptual design for a DM suitable for XAO will be presented. Approaches for a support structure that will maintain the low spatial frequency surface figure of this large (~0.6m) DM and for the electrical interface to the tens of thousands of actuators will be discussed. Finally, performance estimates will be presented.

  2. AO corrected satellite imaging from Mount Stromlo

    NASA Astrophysics Data System (ADS)

    Bennet, F.; Rigaut, F.; Price, I.; Herrald, N.; Ritchie, I.; Smith, C.

    2016-07-01

    The Research School of Astronomy and Astrophysics have been developing adaptive optics systems for space situational awareness. As part of this program we have developed satellite imaging using compact adaptive optics systems for small (1-2 m) telescopes such as those operated by Electro Optic Systems (EOS) from the Mount Stromlo Observatory. We have focused on making compact, simple, and high performance AO systems using modern high stroke high speed deformable mirrors and EMCCD cameras. We are able to track satellites down to magnitude 10 with a Strehl in excess of 20% in median seeing.

  3. AO/NAO Response to Climate Change. 1; Respective Influences of Stratospheric and Tropospheric Climate Changes

    NASA Technical Reports Server (NTRS)

    Rind, D.; Perlwitz, J.; Lonergan, P.

    2005-01-01

    We utilize the GISS Global Climate Middle Atmosphere Model and 8 different climate change experiments, many of them focused on stratospheric climate forcings, to assess the relative influence of tropospheric and stratospheric climate change on the extratropical circulation indices (Arctic Oscillation, AO; North Atlantic Oscillation, NAO). The experiments are run in two different ways: with variable sea surface temperatures (SSTs) to allow for a full tropospheric climate response, and with specified SSTs to minimize the tropospheric change. The results show that tropospheric warming (cooling) experiments and stratospheric cooling (warming) experiments produce more positive (negative) AO/NAO indices. For the typical magnitudes of tropospheric and stratospheric climate changes, the tropospheric response dominates; results are strongest when the tropospheric and stratospheric influences are producing similar phase changes. Both regions produce their effect primarily by altering wave propagation and angular momentum transports, but planetary wave energy changes accompanying tropospheric climate change are also important. Stratospheric forcing has a larger impact on the NAO than on the AO, and the angular momentum transport changes associated with it peak in the upper troposphere, affecting all wavenumbers. Tropospheric climate changes influence both the A0 and NAO with effects that extend throughout the troposphere. For both forcings there is often vertical consistency in the sign of the momentum transport changes, obscuring the difference between direct and indirect mechanisms for influencing the surface circulation.

  4. AO Observations of Three Powerful Radio Galaxies

    SciTech Connect

    de Vries, W; van Bruegel, W; Quirrenbach, A

    2002-08-01

    The host galaxies of powerful radio sources are ideal laboratories to study active galactic nuclei (AGN). The galaxies themselves are among the most massive systems in the universe, and are believed to harbor supermassive black holes (SMBH). If large galaxies are formed in a hierarchical way by multiple merger events, radio galaxies at low redshift represent the end-products of this process. However, it is not clear why some of these massive ellipticals have associated radio emission, while others do not. Both are thought to contain SMBHs, with masses proportional to the total luminous mass in the bulge. It either implies every SMBH has recurrent radio-loud phases, and the radio-quiet galaxies happen to be in the ''low'' state, or that the radio galaxy nuclei are physically different from radio-quiet ones, i.e. by having a more massive SMBH for a given bulge mass. Here we present the first results from our adaptive optics imaging and spectroscopy pilot program on three nearby powerful radio galaxies. Initiating a larger, more systematic AO survey of radio galaxies (preferentially with Laser Guide Star equipped AO systems) has the potential of furthering our understanding of the physical properties of radio sources, their triggering, and their subsequent evolution.

  5. Results of AO simulations for ELTs

    NASA Astrophysics Data System (ADS)

    Conan, Rodolphe; Le Louarn, Miska; Braud, J.; Fedrigo, Enrico; Hubin, Norbert N.

    2003-01-01

    The design and elaboration of Extremely Large Telescopes (ELT) with primary mirror from 20m to 100m face with many challenges: mechanical, optical, computational, etc. To benefit completely of the full potentiality of such facilities, an Adaptive Optics System (AOS) have also to be designed for these telescopes. For whole field--of--view compensation and full sky coverage, the new but promising Multi--Conjugated Adaptive Optics (MCAO) technique has to be envisaged. The first step towards the design of an MCAO system is the numerical simulation. This is the first challenge we have to face. The scale of AO simulations being imposed by the ratio (D/r0), the simulation requirements of a MCAOS for an ELT, in terms of computing power and memory available to store the data, reach and sometimes overcome the capacity of actual computers. In ESO, we have evaluated different hardware and software strategies to achieve MCAO simulations goals. Two codes have been developed to simulate MCAOS using an analytical and an end-to-end model. The goals and advantages/limitations of both approaches is shown. The hardware requirements for both methods is also given through the size of their largest matrices. And finally, results of hardware and software tests for MCAO simulations with PC--cluster and paralleled code are presented.

  6. Diferentes Metodologias Aplicadas ao Ensino de Astronomia

    NASA Astrophysics Data System (ADS)

    Albrecht, E.; Voelzke, M. R.

    2007-08-01

    Espera-se que o educando ao final da educação básica, adquira uma compreensão atualizada das hipóteses, modelos e formas de investigação sobre a origem e evolução do Universo em que vive. O presente trabalho tem como principal objetivo compreender dentre três práticas pedagógicas adotadas no Ensino de Astronomia, na terceira série do Ensino Médio, da Escola Estadual Colônia dos Pescadores, qual melhor cumpre o papel de formação e aprendizagem para vida. A pesquisa preliminar foi através de um questionário onde o intuito foi diagnosticar o conhecimento já existente acerca do tema em questão. O questionário é composto de vinte questões dissertativas e objetivas, onde os educandos das três turmas envolvidas o responderam. Este trabalho utiliza as seguintes metodologias: a tradicional, onde o professor é um repassador de informações, fazendo uso exclusivo de lousa e giz; a segunda também de forma tradicional, porém com auxílio de multimídia para desenvolvimento das aulas e aterceira sob forma de seminários, elaborados e apresentados pelos educandos, no qual o educador faz apenas as intervenções necessárias. Ao final do trabalho os alunos responderão novamente o questionário inicial para diagnosticar dentre as três metodologias utilizadas qual apresentou melhor resultado. Os resultados preliminares obtidos, já podem ser observados e, dos 119 alunos entrevistados, as respostas obtidas são as mais diversas e evidenciam que a grande maioria nunca teve em sua vida escolar o tema Astronomia. Ao serem questionados se já haviam estudado Astronomia as respostas foram: turma A: sim 43%; turma B: sim: 21%; turma C: sim: 24%. Porém quando questionados a respeito do significado de Astronomia observou-se que: turma A: 100% de acertos; turma B: 64% acertos; turma C: 84% de acertos, demonstrando claramente a aprendizagem em diferentes esferas, não dependendo unicamente da escola. Até o presente momento, verificou-se que há interesse em

  7. AO Infrared Imaging of M71 Core

    NASA Astrophysics Data System (ADS)

    Ruberg, Andres; Richer, H.; Brewer, J.; Davis, S.; Hickson, P.; Knigge, C.; Dieball, A.; Hurley, J.; Shara, M.; Hansen, B.; Gebhardt, K.; Fahlman, G.

    2007-05-01

    In this poster we present infrared H and K AO data taken with ALTAIR/NIRI on Gemini North of the globular cluster Messier 71. This data represents approximately 22ks of observations in H and 17ks in K, in a field 22x22 arcsec centered on the core of the cluster. These data were secured under superb conditions and will provide an excellent opportunity to pursue our scientific goals. These goals include the observation of the end of hydrogen-burning main sequence in a moderately metal-rich globular cluster and, by fitting the brightness profile and looking for deviations from a King model, we will search for evidence for a central black hole in this cluster.

  8. Review of AO calibrations, or how to best educate your AO system

    NASA Astrophysics Data System (ADS)

    Kolb, Johann

    2016-07-01

    If the Real-Time Computer is the heart of an AO system, the Wavefront Sensor (WFS) its eyes, the Deformable Mirror (DM) its hands and the control strategy its nervous system, the sum of all those parts is made into a harmonious entity thanks to calibrations. This paper does not have the ambition to provide an overview of all the currently existing calibration strategies, but rather to focus on a few challenging problems and their recent evolution in the era of adaptive telescopes, mostly based on the experience of ESO's Adaptive Optics Instruments in general and the AO Facility in particular. Single most important calibration in post-focal AO system, the recording of the Interaction Matrix (IM) between WFS and DM has since long evolved to use fast modulation techniques, has shown to be feasible on-sky and is now almost free from measurements thanks to its pseudo-synthetic generation, quasi-mandatory solution in an adaptive telescope. Pseudo- because it requires an unprecedented knowledge of the components' characteristics, especially the WFS, DM and the optical registration between the two. Bigger telescopes and the use of Laser Guide Stars (LGS) also mean that the properties of the system will change in time and thus need to be constantly updated thanks to online diagnosis tools for spot size measurement, atmosphere monitoring, Wavefront Sensing and control optimization. New loops come into play like the one to minimize LGS Jitter and the one taking over the telescope active optics by means of offloading the DM low orders, and they all require calibration. More calibration means more time and one has to carefully balance the calibrations that require precious telescope night time, day time or for the best, no telescope time at all. Their importance sometimes underestimated, calibrations have repeatedly shown to be a vital part in the optimum functioning of present and future AO systems.

  9. LGS-AO Imaging of Every Kepler Planet Candidate: the Robo-AO KOI Survey

    NASA Astrophysics Data System (ADS)

    Baranec, Christoph; Law, Nicholas; Morton, Timothy; Ziegler, Carl; Nofi, Larissa; Atkinson, Dani; Riddle, Reed

    2015-12-01

    The Robo-AO Kepler Planetary Candidate Survey is observing every Kepler planet candidate host star with laser adaptive optics imaging, to search for blended nearby stars which may be physically associated companions and/or responsible for transit false positives. We will present the results from searching for companions around over 3,000 Kepler planet hosts in 2012-2015. We will describe our first data release covering 715 planet candidate hosts, and give a preview of ongoing results including improved statistics on the likelihood of false positive planet detections in the Kepler dataset, many new planets in multiple star systems, and new exotic multiple star systems containing Kepler planets. We will also describe the automated Robo-AO survey data reduction methods, including a method of using the large ensemble of target observations as mutual point-spread-function references, along with a new automated companion-detection algorithm designed for extremely large adaptive optics surveys. Our first data release covered 715 objects, searching for companions from 0.15” to 2.5” separation with contrast up to 6 magnitudes. We measured the overall nearby-star-probability for Kepler planet candidates to be 7.4+/-1.0%, and we will detail the variations in this number with stellar host parameters. We will also discuss plans to extend the survey to other transiting planet missions such as K2 and TESS as Robo-AO is in the process of being re-deployed to the 2.1-m telescope at Kitt Peak for 3 years and a higher-contrast Robo-AO system is being developed for the 2.2-m UH telescope on Maunakea.

  10. Directly Imaging Planets with SCExAO: First Results

    NASA Astrophysics Data System (ADS)

    Currie, Thayne M.; Guyon, Olivier; Jovanovic, Nemanja; Lozi, Julien; Tamura, Motohide; Kudo, Tomoyuki; Uyama, Taichi; Garcia, Eugenio

    2017-01-01

    We present the first science results from the newly commissioned Subaru Coronagraphic Extreme Adaptive Optics project, an experimental system dedicated to image faint jovian planets around nearby stars. SCExAO is now achieving true extreme AO capability. We describe the typical performance of SCExAO, the first images of benchmark exoplanets and planet-forming disks, and SCExAO’s first science results. Finally, we briefly chart the path forward for SCExAO to achieve its full scientific capability, including imaging mature planets in reflected light.

  11. Electromagnetic DM technology meets future AO demands

    NASA Astrophysics Data System (ADS)

    Hamelinck, Roger; Rosielle, Nick; Steinbuch, Maarten; Doelman, Niek

    New deformable mirror technology is developed by the Technische Universiteit Eindhoven, Delft University of Technology and TNO Science and Industry. Several prototype adaptive deformable mirrors are realized mirrors, up to 427 actuators and ∅150mm diameter, with characteristics suitable for future AO systems. The prototypes consist of a 100µm thick, continuous facesheet on which low voltage, electromagnetic, push-pull actuators impose out-of-plane displacements. The variable reluctance actuators with ±10µm stroke and nanometer resolution are located in a standard actuator module. Each module with 61 actuators connects to a single PCB with dedicated, 16 bit, PWM based, drivers. A LVDS multi-drop cable connects up to 32 actuator modules. With the actuator module, accompanying PCB and multi-drop system the deformable mirror technology is made modular in its mechanics and electronics. An Ethernet-LVDS bridge enables any commercial PC to control the mirror using the UDP standard. Latest results of the deformable mirror technology development are presented.

  12. WIYN active optics: a platform for AO

    NASA Astrophysics Data System (ADS)

    Code, Arthur D.; Claver, Charles F.; Goble, Larry W.; Jacoby, George H.; Sawyer, David G.

    1998-09-01

    The WIYN 3.5 meter telescope is situated on the southwest ridge of Kitt Peak yielding excellent atmosphere seeing conditions. As such, the telescope and enclosure design was directed towards exploiting this feature. The primary mirror was spun cast and figured by the Steward Observatory Mirror Laboratory and the secondary mirror by Contraves. In both cases the performance exceeded the design specifications. The borosilicate primary is actively temperature controlled to within 0.2 C of the desired temperature, typically 0.5 degrees C below the ambient air. The telescope structure is also temperature controlled and the enclosure is opened to the outside ion all sides, which all heat sources are vented to ducts carrying air downwind of the facility. The primary mirror is actively controlled for low order aberrations by 66 axial actuators which are adjusted open loop via force matrix look-up tables and closed loop via real-time wavefront curvature sensing measurements. The active optics also included real-time collimation and focus control. The telescope drive and guider are capable of providing tracking to a few hundredths of a second of arc. By employing active telescope control at this level, it is possible to maintain telescope and local wavefront distortion to a level where atmospheric effects dominate the image quality. Since a significant fraction of the power in the atmospheric disturbances is contained in image motion the first step in adaptive optics control will be simple tip tilt. Studies of higher order AO system are being carried out, as well as additional test characterizing the telescope and site. It is intended to continue such studies in an attempt to establish long term variances.

  13. NFIRAOS Multiconjugate AO System for TMT

    NASA Astrophysics Data System (ADS)

    Herriot, Glen; Andersen, David; Atwood, Jenny; Byrnes, Peter; Boyer, Corinne; Caputa, Kris; Correia, Carlos; Dunn, Jennifer; Ellerbroek, Brent; Fitzsimmons, Joeleff; Gilles, Luc; Hickson, Paul; Hill, Alexis; Pazder, John; Reshetov, Vlad; Smith, Malcolm; Véran, Jean-Pierre; Wang, Lianqi; Wevers, Ivan

    2011-09-01

    NFIRAOS, the Adaptive Optics system for the Thirty Meter Telescope, is a Multiconjugate Adaptive Optics System of order 60x60 with two deformable mirrors and six laser guide star wavefront sensors. NFIRAOS is 8 x 10 x 5 m (L x W x H) on a Nasmyth Platform and supports three client instruments operating over 0.8 - 2.5 μm wavelength range. In this paper we discuss: NFIRAOS' requirements and architecture; changes to NFIRAOS since the last AO4ELT conference; interior details of NFIRAOS; interfaces to instruments; integration and verification plans. Top-level science requirements include 50% sky coverage at the galactic pole with <187 nm wavefront error. Astrometry is an important science driver - to minimize image distortion, we have recently revised the optical design to use four off-axis paraboloidal mirrors. We have vastly simplified the laser WFS zoom optics and moved them inside the cold enclosure. To control image magnification, differential magnification and tip/tilt/focus, NFIRAOS' client instruments have three low-order warfront sensors monitoring near-infrared natural guide stars. These stars are sharpened by NFIRAOS, which assists sky coverage. NFIRAOS will have high throughput and low thermal background - it will be cooled to -30 °C. The insulated walls have a buried cold plate to intercept heat leakage and isothermalize the interior of NFIRAOS. Instruments have stringent requirements on heat leakage and must provide their own rotator and interface to NFIRAOS, including a rotating seal. For wavelength and flat field calibration of client instruments, a NFIRAOS Science Calibration Unit (NSCU) feeds light in the entrance window, through NFIRAOS, to instruments. Inside NFIRAOS are deployable light sources simulating natural and laser guide stars, a focal plane mask with pinholes illuminated by the NSCU, as well as a turbulence phase screen. A prototype screen has been manufactured by magneto-rheological machining. We are currently updating the NFIRAOS

  14. Robo-AO: Performance and Characterization at Palomar Observatory

    NASA Astrophysics Data System (ADS)

    Tendulkar, Shriharsh P.; Baranec, C.; Riddle, R. L.; Ramaprakash, A. N.; Law, N. M.; Kulkarni, S. R.; Dekany, R.; Bui, K.; Davis, J.; Burse, M.; Das, H.; Punnadi, S.; Chordia, P.

    2013-01-01

    Hosted at the Palomar 60-inch telescope, Robo-AO is the world's first completely autonomous, laser-beacon supported adaptive optics (AO) system, delivering diffraction-limited images in the visible and IR wavelengths. With simultaneous turbulence monitoring using a MASS-DIMM instrument, we have characterized the performance of Robo-AO as a function of local seeing, turbulence profile, laser return power and the brightness of the tip-tilt star. We shall present the various AO metrics: The full-width at half maxima of the point spread function, the Strehl ratio, the isoplanatic angle and their variations with the atmospheric and operating conditions. Strategies for optimizing robotic AO observations based on varying conditions will be discussed.

  15. The path to visible extreme adaptive optics with MagAO-2K and MagAO-X

    NASA Astrophysics Data System (ADS)

    Males, Jared R.; Close, Laird M.; Guyon, Olivier; Morzinski, Katie M.; Hinz, Philip; Esposito, Simone; Pinna, Enrico; Xompero, Marco; Briguglio, Runa; Riccardi, Armando; Puglisi, Alfio; Mazin, Ben; Ireland, Michael J.; Weinberger, Alycia; Conrad, Al; Kenworthy, Matthew; Snik, Frans; Otten, Gilles; Jovanovic, Nemanja; Lozi, Julien

    2016-07-01

    The next generation of extremely large telescopes (ELTs) have the potential to image habitable rocky planets, if suitably optimized. This will require the development of fast high order "extreme" adaptive optics systems for the ELTs. Located near the excellent site of the future GMT, the Magellan AO system (MagAO) is an ideal on-sky testbed for high contrast imaging development. Here we discuss planned upgrades to MagAO. These include improvements in WFS sampling (enabling correction of more modes) and an increase in speed to 2000 Hz, as well as an H2RG detector upgrade for the Clio infrared camera. This NSF funded project, MagAO-2K, is planned to be on-sky in November 2016 and will significantly improve the performance of MagAO at short wavelengths. Finally, we describe MagAO-X, a visible-wavelength extreme-AO "afterburner" system under development. MagAO-X will deliver Strehl ratios of over 80% in the optical and is optimized for visible light coronagraphy.

  16. First closed-loop visible AO test results for the advanced adaptive secondary AO system for the Magellan Telescope: MagAO's performance and status

    NASA Astrophysics Data System (ADS)

    Close, Laird M.; Males, Jared R.; Kopon, Derek A.; Gasho, Victor; Follette, Katherine B.; Hinz, Phil; Morzinski, Katie; Uomoto, Alan; Hare, Tyson; Riccardi, Armando; Esposito, Simone; Puglisi, Alfio; Pinna, Enrico; Busoni, Lorenzo; Arcidiacono, Carmelo; Xompero, Marco; Briguglio, Runa; Quiros-Pacheco, Fernando; Argomedo, Javier

    2012-07-01

    The heart of the 6.5 Magellan AO system (MagAO) is a 585 actuator adaptive secondary mirror (ASM) with <1 msec response times (0.7 ms typically). This adaptive secondary will allow low emissivity and high-contrast AO science. We fabricated a high order (561 mode) pyramid wavefront sensor (similar to that now successfully used at the Large Binocular Telescope). The relatively high actuator count (and small projected ~23 cm pitch) allows moderate Strehls to be obtained by MagAO in the “visible” (0.63-1.05 μm). To take advantage of this we have fabricated an AO CCD science camera called "VisAO". Complete “end-to-end” closed-loop lab tests of MagAO achieve a solid, broad-band, 37% Strehl (122 nm rms) at 0.76 μm (i’) with the VisAO camera in 0.8” simulated seeing (13 cm ro at V) with fast 33 mph winds and a 40 m Lo locked on R=8 mag artificial star. These relatively high visible wavelength Strehls are enabled by our powerful combination of a next generation ASM and a Pyramid WFS with 400 controlled modes and 1000 Hz sample speeds (similar to that used successfully on-sky at the LBT). Currently only the VisAO science camera is used for lab testing of MagAO, but this high level of measured performance (122 nm rms) promises even higher Strehls with our IR science cameras. On bright (R=8 mag) stars we should achieve very high Strehls (>70% at H) in the IR with the existing MagAO Clio2 (λ=1-5.3 μm) science camera/coronagraph or even higher (~98% Strehl) the Mid-IR (8-26 microns) with the existing BLINC/MIRAC4 science camera in the future. To eliminate non-common path vibrations, dispersions, and optical errors the VisAO science camera is fed by a common path advanced triplet ADC and is piggy-backed on the Pyramid WFS optical board itself. Also a high-speed shutter can be used to block periods of poor correction. The entire system passed CDR in June 2009, and we finished the closed-loop system level testing phase in December 2011. Final system acceptance (

  17. AO 0235+164 and Surrounding Field: Surprising HST Results

    NASA Technical Reports Server (NTRS)

    Burbidge, E. M.; Beaver, E. A.; Cohen, Ross D.; Junkkarinen, V. T.; Lyons, R. W.

    1996-01-01

    Results obtained with the Hubble Space Telescope on the highly variable radio, x-ray, and gamma-ray emitting QSO (or BL Lac object) AO 0235 + 164 are presented and analyzed. WFPC2 images were obtained in 1994 June, when AO 0235 + 164 was bright (m approx. 17), and the results are described in Sec. 3. After subtraction of the PSF of the QSO, hereafter called AO following the nomenclature of Yanny et al. (1989), the companion object named A, 2 sec south of AO, is discovered not to be an elliptical galaxy as hypothesized earlier, but to be an AGN object, with a central UV-bright point-source nucleus and faint surrounding nebulosity extending to AO. The second companion object 1.3 sec east of AO discovered by Yanny et al. (1989) and named object Al, appears more like a normal spiral galaxy. We have measured the positions, luminosities, and colors of some 30 faint objects in the field around AO 0235 + 16; most are extended and may be star-forming galaxies in a loose group or cluster. Our most surprising result of the HST observations comes from FOS spectra obtained in 1995 July, discussed in Sec. 4. Because of a positioning error of the telescope and AO's faintness at that time (m approx. 20), object A was observed instead of the intended target AO. Serendipitously, we discovered A to have broad deep BALQSO-type absorptions of C IV, Si IV, N V shortward of broad emissions. A is thus ejecting high velocity, highly ionized gas into the surrounding IGM. We discuss in Sec. 5 the relationship of the objects in the central 10 sec X 1O sec region around AO, where redshifts z(sub e) = 0.94, z(sub a) = 0.524, 0.851 in AO, (sub e) = 0.524 and Z(sub BAL)=0.511 in A, are found. We hypothesize that some of the 30 faint objects in the 77 sec. x 77 sec. field may be part of a large star-forming region at z approx. 0.5, as suggested for a few objects by Yanny et al. (1989). The proximity of two highly active extragalactic objects, AO 0235+164 and its AGN companion A, is remarkable and

  18. The Subaru Coronagraphic Extreme AO Project: Progress and Upgrades

    NASA Astrophysics Data System (ADS)

    Jovanovic, Nemanja; Martinache, F.; Guyon, O.; Clergeon, C.; Garrel, V.

    2013-01-01

    The Subaru Coronagraphic Extreme AO (SCExAO) instrument consists of a high performance Phase Induced Amplitude Apodisation (PIAA) coronagraph combined with an extreme Adaptive Optics (AO) system operating in the near-infrared (H band). The extreme AO system driven by the 2000 element deformable mirror will allow for Strehl ratios>90% to be achieved in the H-band when it goes closed loop. This makes the SCExAO instrument a powerful platform for high contrast imaging down to angular separations of the order of 1 λ/D. In this paper we report on the recent progress in regards to the development of the instrument, which includes the addition of a visible bench that makes use of the light at shorter wavelengths not currently utilized by SCExAO and closing the loop on the tip/tilt wavefront sensor. We will also discuss two exciting guest instruments which will expand the capabilities of SCExAO over the next few years; namely CHARIS which is a integral field spectrograph as well as VAMPIRES, a visible aperture masking experiment based on polarimetric analysis of circumstellar disks.

  19. The Robo-AO automated intelligent queue system

    NASA Astrophysics Data System (ADS)

    Riddle, Reed L.; Hogstrom, Kristina; Papadopoulos, Athanasios; Baranec, Christoph; Law, Nicholas M.

    2014-07-01

    Robo-AO is the first automated laser adaptive optics instrument. In just its second year of scientific operations, it has completed the largest adaptive optics surveys to date, each comprising thousands of targets. Robo-AO uses a fully automated queue scheduling system that selects targets based on criteria entered on a per observing program or per target basis, and includes the ability to coordinate with US Strategic Command automatically to avoid lasing space assets. This enables Robo-AO to select among thousands of targets at a time, and achieve an average observation rate of approximately 20 targets per hour.

  20. SCExAO: First Results and On-Sky Performance

    NASA Technical Reports Server (NTRS)

    Currie, Thayne; Guyon, Olivier; Martinache, Frantz; Clergeon, Christophe; McElwain, Michael; Thalmann, Christian; Jovanovic, Nemanja; Singh, Garima; Kudo, Tomoyuki

    2013-01-01

    We present new on-sky results for the Subaru Coronagraphic Extreme Adaptive Optics imager (SCExAO) verifying and quantifying the contrast gain enabled by key components: the closed-loop coronagraphic low-order wavefront sensor (CLOWFS) and focal plane wavefront control ("speckle nulling"). SCExAO will soon be coupled with a high-order, Pyramid wavefront sensor which will yield greater than 90% Strehl ratio and enable 10(exp 6) -10(exp 7) contrast at small angular separations allowing us to image gas giant planets at solar system scales. Upcoming instruments like VAMPIRES, FIRST, and CHARIS will expand SCExAO's science capabilities.

  1. SCExAO: First Results and On-Sky Performance

    NASA Astrophysics Data System (ADS)

    Currie, Thayne; Guyon, Olivier; Martinache, Frantz; Clergeon, Christophe; McElwain, Michael; Thalmann, Christian; Jovanovic, Nemanja; Singh, Garima; Kudo, Tomoyuki

    2014-01-01

    We present new on-sky results for the Subaru Coronagraphic Extreme Adaptive Optics imager (SCExAO) verifying and quantifying the contrast gain enabled by key components: the closed-loop coronagraphic low-order wavefront sensor (CLOWFS) and focal plane wavefront control (``speckle nulling''). SCExAO will soon be coupled with a high-order, Pyramid wavefront sensor which will yield > 90% Strehl ratio and enable 106-107 contrast at small angular separations allowing us to image gas giant planets at solar system scales. Upcoming instruments like VAMPIRES, FIRST, and CHARIS will expand SCExAO's science capabilities.

  2. LGS-AO Imaging of Every Kepler Planet Candidate: the Robo-AO KOI Survey

    NASA Astrophysics Data System (ADS)

    Law, Nicholas Michael; Baranec, Christoph; Morton, Timothy; Ziegler, Carl; Atkinson, Dani; Riddle, Reed

    2015-08-01

    The Robo-AO Kepler Planetary Candidate Survey is observing every Kepler planet candidate host star with laser adaptive optics imaging, to search for blended nearby stars which may be physically associated companions and/or responsible for transit false positives. We will present the results from searching for companions around over 3,000 Kepler planet hosts in 2012-2015. We will describe our first data release covering 715 planet candidate hosts, and give a preview of ongoing results including improved statistics on the likelihood of false positive planet detections in the Kepler dataset, many new planets in multiple star systems, and new exotic multiple star systems containing Kepler planets.We will also describe the automated Robo-AO survey data reduction methods, including a method of using the large ensemble of target observations as mutual point-spread-function references, along with a new automated companion-detection algorithm designed for extremely large adaptive optics surveys.Our first data release covered 715 objects, searching for companions from 0.15” to 2.5” separation with contrast up to 6 magnitudes. We measured the overall nearby-star-probability for Kepler planet candidates to be 7.4+/-1.0%, and we will detail the variations in this number with stellar host parameters. We will also discuss several KOIs of particular interest, including KOI-191 and KOI-1151, which are both multi-planet systems with detected stellar companions whose unusual planetary system architecture might be best explained if they are ``coincident multiple'' systems, with several transiting planets shared between the two stars. Finally, we will discuss and update the 98%-confidence evidence from our survey that third bodies in star/planet systems produce an excess of close-in giant planets.

  3. Real-time processing for the ATST AO system

    NASA Astrophysics Data System (ADS)

    Richards, K.; Rimmele, T.

    The real-time processing requirements for the four meter Advanced Technology Solar Telescope extended source high order adaptive optics system will be approximately 15 times that of the Dunn Solar Telescope AO systems on which the ATST AO system is based. The ATST AO, with its approximately 1232 subapertures, will use massively parallel processing and is based on Analog Devices TigerSHARC DSPs as the central processing units. We will discuss the requirements for processing and data handling and the architecture of the correlating Shack-Hartmannn and reconstructor processing unit and present the results of bench-mark testing of the DSP hardware that was selected for the ATST AO system.

  4. Visible AO Observations at Halpha for Accreting Young Planets

    NASA Astrophysics Data System (ADS)

    Close, L. M.; Follette, K.; Males, J. R.; Morzinski, K.; Rodigas, T. J.; Hinz, P.; Wu, Y.-L.; Apai, D.; Najita, J.; Puglisi, A.; Esposito, S.; Riccardi, A.; Bailey, V.; Xompero, M.; Briguglio, R.; Weinberger, A.

    2014-01-01

    We utilized the new high-order (250-378 mode) Magellan Adaptive Optics system (MagAO) to obtain very high-resolution science in the visible with MagAO's VisAO CCD camera. In the good-median seeing conditions of Magellan (0.5-0.7'') we find MagAO delivers individual short exposure images as good as 19 mas optical resolution. Due to telescope vibrations, long exposure (60s) r' (0.63μm) images are slightly coarser at FWHM = 23-29 mas (Strehl ~ 28%) with bright (R < 9 mag) guide stars. These are the highest resolution filled-aperture images published to date. Images of the young (~ 1 Myr) Orion Trapezium θ1 Ori A, B, and C cluster members were obtained with VisAO. In particular, the 32 mas binary θ1 Ori C 1 C 2 was easily resolved in non-interferometric images for the first time. Relative positions of the bright trapezium binary stars were measured with ~ 0.6-5 mas accuracy. In the second commissioning run we were able to correct 378 modes and achieved good contrasts (Strehl>20% on young transition disks at Hα). We discuss the contrasts achieved at Hα and the possibility of detecting low mass (~ 1-5 Mjup) planets (past 5AU) with our new SAPPHIRES survey with MagAO at Hα.

  5. LDEF: Dosimetric measurement results (AO 138-7 experiment)

    NASA Technical Reports Server (NTRS)

    Bourrieau, J.

    1993-01-01

    One of the objectives of the AO 138-7 experiment on board the Long Duration Exposure Facility (LDEF) was a total dose measurement with Thermo Luminescent Detectors (TLD 100). Two identical packages, both of them including five TLD's inside various aluminum shields, are exposed to the space environment in order to obtain the absorbed dose profile. Radiation fluence received during the total mission length was computed, taking into account the trapped particles (AE8 and AP8 models during solar maximum and minimum periods) and the cosmic rays; due to the magnetospheric shielding the solar proton fluences are negligible on the LDEF orbit. The total dose induced by these radiations inside a semi infinite plane shield of aluminum are computed with the radiation transport codes available at DERTS. The dose profile obtained is in good agreement with the evaluation by E.V. Benton. TLD readings are performed after flight; due to the mission duration increase a post flight calibration was necessary in order to cover the range of the in flight induced dose. The results obtained, similar (plus or minus 30 percent) for both packages, are compared with the dose profile computation. For thick shields it seems that the measurements exceed the forecast (about 40 percent). That can be due to a cosmic ray and trapped proton contributions coming from the backside (assumed as perfectly shielded by the LDEF structure in the computation), or to an underestimate of the proton or cosmic ray fluences. A fine structural shielding analysis should be necessary in order to determine the origin of this slight discrepancy between forecast and in flight measurements. For the less shielded dosimeters, mainly exposed to the trapped electron flux, a slight overestimation of the dose (less than 40 percent) appears. Due to the dispersion of the TLD's response, this cannot be confirmed. In practice these results obtained on board LDEF, with less than a factor 1.4 between measurements and forecast

  6. LDEF: Dosimetric measurement results (AO 138-7 experiment)

    NASA Astrophysics Data System (ADS)

    Bourrieau, J.

    1993-04-01

    One of the objectives of the AO 138-7 experiment on board the Long Duration Exposure Facility (LDEF) was a total dose measurement with Thermo Luminescent Detectors (TLD 100). Two identical packages, both of them including five TLD's inside various aluminum shields, are exposed to the space environment in order to obtain the absorbed dose profile. Radiation fluence received during the total mission length was computed, taking into account the trapped particles (AE8 and AP8 models during solar maximum and minimum periods) and the cosmic rays; due to the magnetospheric shielding the solar proton fluences are negligible on the LDEF orbit. The total dose induced by these radiations inside a semi infinite plane shield of aluminum are computed with the radiation transport codes available at DERTS. The dose profile obtained is in good agreement with the evaluation by E.V. Benton. TLD readings are performed after flight; due to the mission duration increase a post flight calibration was necessary in order to cover the range of the in flight induced dose. The results obtained, similar (plus or minus 30 percent) for both packages, are compared with the dose profile computation. For thick shields it seems that the measurements exceed the forecast (about 40 percent). That can be due to a cosmic ray and trapped proton contributions coming from the backside (assumed as perfectly shielded by the LDEF structure in the computation), or to an underestimate of the proton or cosmic ray fluences. A fine structural shielding analysis should be necessary in order to determine the origin of this slight discrepancy between forecast and in flight measurements. For the less shielded dosimeters, mainly exposed to the trapped electron flux, a slight overestimation of the dose (less than 40 percent) appears. Due to the dispersion of the TLD's response, this cannot be confirmed. In practice these results obtained on board LDEF, with less than a factor 1.4 between measurements and forecast

  7. Beyond the Blur: Construction and Characterization of the First Autonomous AO System, and, An AO Survey of Magnetar Proper Motions

    NASA Astrophysics Data System (ADS)

    Tendulkar, Shriharsh Prakash

    Adaptive optics (AO) corrects distortions created by atmospheric turbulence and delivers diffraction-limited images on ground-based telescopes. The vastly improved spatial resolution and sensitivity has been utilized for studying everything from the magnetic fields of sunspots upto the internal dynamics of high-redshift galaxies. This thesis about AO science from small and large telescopes is divided into two parts: Robo-AO and magnetar kinematics. In the first part, I discuss the construction and performance of the world's first fully autonomous visible light AO system, Robo-AO, at the Palomar 60-inch telescope. Robo-AO operates extremely efficiently with an overhead < 50s, typically observing about 22 targets every hour. We have performed large AO programs observing a total of over 7,500 targets since May 2012. In the visible band, the images have a Strehl ratio of about 10% and achieve a contrast of upto 6 magnitudes at a separation of 1‧‧. The full-width at half maximum achieved is 110-130 milli-arcsecond. I describe how Robo-AO is used to constrain the evolutionary models of low-mass pre-main-sequence stars by measuring resolved spectral energy distributions of stellar multiples in the visible band, more than doubling the current sample. I conclude this part with a discussion of possible future improvements to the Robo-AO system. In the second part, I describe a study of magnetar kinematics using high-resolution near-infrared (NIR) AO imaging from the 10-meter Keck II telescope. Measuring the proper motions of five magnetars with a precision of upto 0.7 milli-arcsecond/yr -1, we have more than tripled the previously known sample of magnetar proper motions and proved that magnetar kinematics are equivalent to those of radio pulsars. We conclusively showed that SGR 1900+14 and SGR 1806-20 were ejected from the stellar clusters with which they were traditionally associated. The inferred kinematic ages of these two magnetars are 6 +/- 1.8 kyr and 650 +/-3 00

  8. Radiation Transport

    SciTech Connect

    Urbatsch, Todd James

    2015-06-15

    We present an overview of radiation transport, covering terminology, blackbody raditation, opacities, Boltzmann transport theory, approximations to the transport equation. Next we introduce several transport methods. We present a section on Caseology, observing transport boundary layers. We briefly broach topics of software development, including verification and validation, and we close with a section on high energy-density experiments that highlight and support radiation transport.

  9. Period Studies of Close Binaries, AO Cam and AW Cam

    NASA Astrophysics Data System (ADS)

    Kim, Chun-Hwey; Han, Won-Yong; Nha, Il-Seong

    1992-06-01

    Photoelectric observations of close binary stars, AO Cam and AW Cam, were made during the 1984 observing season with the 61cm reflector at the Sobaeksan Observatory. One time of primary minimum for AO Cam and three primary epochs for AW Cam were derived from the observation of these two system. Times of minimum light of these two binaries collected from literature were analyzed with a least square fitting method. New improved light elements for AO Cam and AW Cam were determined. The orbital period of AO Cam had been constant from October, 1980(JD 2444520) to February, 1985(JD 2446107). However, one secondary time of minimum(JD 2447864.7879) of AO Cam published recently by Mullis and Faulkner(1991) shows large deviation of about 4.6 minutes (0.d0032) from the one predicted by our new light elements. Future observations of times of minima for this system are needed to test this period change. The orbital period of AW Cam has been constant as P = 0d77134645 for about sixty years from the early 1930's to the present.

  10. Characterizing and mitigating vibrations for SCExAO

    NASA Astrophysics Data System (ADS)

    Lozi, Julien; Guyon, Olivier; Jovanovic, Nemanja; Singh, Garima; Goebel, Sean; Norris, Barnaby; Okita, Hirofumi

    2016-07-01

    The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument, under development for the Subaru Telescope, has currently the fastest on-sky wavefront control loop, with a pyramid wavefront sensor running at 3.5 kHz. But even at that speed, we are still limited by low-frequency vibrations. The current main limitation was found to be vibrations attributed mainly to the rotation of the telescope. Using the fast wavefront sensors, cameras and accelerometers, we managed to identify the origin of most of the vibrations degrading our performance. Low-frequency vibrations are coming from the telescope drive in azimuth and elevation, as well as the elevation encoders when the target is at transit. Other vibrations were found at higher frequency coming from the image rotator inside Subaru's adaptive optics facility AO188. Different approaches are being implemented to take care of these issues. The PID control of the image rotator has been tuned to reduce their high-frequency contribution. We are working with the telescope team to tune the motor drives and reduce the impact of the elevation encoder. A Linear Quadratic Gaussian controller (LQG, or Kalman filter) is also being implemented inside SCExAO to control these vibrations. These solutions will not only improve significantly SCExAOs performance, but will also help all the other instruments on the Subaru Telescope, especially the ones behind AO188. Ultimately, this study will also help the development of the TMT, as these two telescopes share very similar drives.

  11. Chamber transport

    SciTech Connect

    OLSON,CRAIG L.

    2000-05-17

    Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system.

  12. A pyramid sensor based AO system for Extremely Large Telescopes

    NASA Astrophysics Data System (ADS)

    Quirós-Pacheco, F.; Pinna, E.; Esposito, S.; Riccardi, A.; Rabien, S.

    2011-09-01

    Since the introduction of the pyramid wavefront sensor in the mid 90s, various authors have shown both theoretically and with the aid of simulations that pyramid sensors can achieve a better performance than traditional Shack-Hartmann wavefront sensors. Recently the First-Light AO system (FLAO) at the Large Binocular Telescope has demonstrated excellent on sky performance achieved with a pyramid based system. Motivated by these results, we will present in this paper a first heuristic analysis scaling up the FLAO performance to the case of an Extremely Large Telescope (ELT). We support our arguments with preliminary numerical simulations for the case of the European ELT using the M4 adaptive corrector and a properly matched pyramid sensor. Such a system could be used as a first-light natural guide-star AO system for the European ELT offering the advantages of a demonstrated AO system with practically off-the-shelf technology.

  13. Second generation Robo-AO instruments and systems

    NASA Astrophysics Data System (ADS)

    Baranec, Christoph; Riddle, Reed; Law, Nicholas M.; Chun, Mark R.; Lu, Jessica R.; Connelley, Michael S.; Hall, Donald; Atkinson, Dani; Jacobson, Shane

    2014-07-01

    The prototype Robo-AO system at the Palomar Observatory 1.5-m telescope is the world's first fully automated laser adaptive optics instrument. Scientific operations commenced in June 2012 and more than 12,000 observations have since been performed at the ~0.12" visible-light diffraction limit. Two new infrared cameras providing high-speed tip-tilt sensing and a 2' field-of-view will be integrated in 2014. In addition to a Robo-AO clone for the 2-m IGO and the natural guide star variant KAPAO at the 1-m Table Mountain telescope, a second generation of facility-class Robo-AO systems are in development for the 2.2-m University of Hawai'i and 3-m IRTF telescopes which will provide higher Strehl ratios, sharper imaging, ~0.07", and correction to λ = 400 nm.

  14. High-Performance CCSDS AOS Protocol Implementation in FPGA

    NASA Technical Reports Server (NTRS)

    Clare, Loren P.; Torgerson, Jordan L.; Pang, Jackson

    2010-01-01

    The Consultative Committee for Space Data Systems (CCSDS) Advanced Orbiting Systems (AOS) space data link protocol provides a framing layer between channel coding such as LDPC (low-density parity-check) and higher-layer link multiplexing protocols such as CCSDS Encapsulation Service, which is described in the following article. Recent advancement in RF modem technology has allowed multi-megabit transmission over space links. With this increase in data rate, the CCSDS AOS protocol implementation needs to be optimized to both reduce energy consumption and operate at a high rate.

  15. Initial Performance of the Keck AO Wavefront Controller System

    SciTech Connect

    Johansson, E M; Acton, D S; An, J R; Avicola, K; Beeman, B V; Brase, J M; Carrano, C J; Gathright, J; Gavel, D T; Hurd, R L; Lai, O; Lupton, W; Macintosh, B A; Max, C E; Olivier, S S; Shelton, J C; Stomski, P J; Tsubota, K; Waltjen, K E; Watson, J A; Wizinowich, P L

    2001-03-01

    The wavefront controller for the Keck Observatory AO system consists of two separate real-time control loops: a tip-tilt control loop to remove tilt from the incoming wavefront, and a deformable mirror control loop to remove higher-order aberrations. In this paper, we describe these control loops and analyze their performance using diagnostic data acquired during the integration and testing of the AO system on the telescope. Disturbance rejection curves for the controllers are calculated from the experimental data and compared to theory. The residual wavefront errors due to control loop bandwidth are also calculated from the data, and possible improvements to the controller performance are discussed.

  16. Initial performance of the Keck AO wavefront controller system

    NASA Astrophysics Data System (ADS)

    Johansson, Erik M.; Acton, D. Scott; An, Jong R.; Avicola, Kenneth; Beeman, Bart V.; Brase, James M.; Carrano, Carmen J.; Gathright, John; Gavel, Donald T.; Hurd, Randall L.; Lai, Olivier; Lupton, William; Macintosh, Bruce A.; Max, Claire E.; Olivier, Scot S.; Shelton, J. Christopher; Stomski, Paul J.; Tsubota, Kevin; Waltjen, Kenneth E.; Watson, James A.; Wizinowich, Peter L.

    2000-07-01

    The wavefront controller for the Keck Observatory AO system consists of two separate real-time control loops: a tip-tilt control loop to remove tilt from the incoming wavefront, and a deformable mirror control loop to remove higher-order aberrations. In this paper, we describe these control loops and analyze their performance using diagnostic data acquired during the integration and testing of the AO system on the telescope. Disturbance rejection curves for the controllers are calculated from the experimental data and compared to theory. The residual wavefront errors due to control loop bandwidth are also calculated from the data, and possible improvements to the controller performance are discussed.

  17. Pupil Transportation.

    ERIC Educational Resources Information Center

    Stollar, Dewey H.

    The purpose of this NEFP satellite study is to provide an overview of pupil transportation. The first phase of the study discusses the early legal and financial bases for student transportation, the second the current status of student transportation, and the third the future status of student transportation needs and financing for 1980.…

  18. A Prediction of the Damping Properties of Hindered Phenol AO-60/polyacrylate Rubber (AO-60/ACM) Composites through Molecular Dynamics Simulation

    NASA Astrophysics Data System (ADS)

    Yang, Da-Wei; Zhao, Xiu-Ying; Zhang, Geng; Li, Qiang-Guo; Wu, Si-Zhu

    2016-05-01

    Molecule dynamics (MD) simulation, a molecular-level method, was applied to predict the damping properties of AO-60/polyacrylate rubber (AO-60/ACM) composites before experimental measures were performed. MD simulation results revealed that two types of hydrogen bond, namely, type A (AO-60) -OH•••O=C- (ACM), type B (AO-60) - OH•••O=C- (AO-60) were formed. Then, the AO-60/ACM composites were fabricated and tested to verify the accuracy of the MD simulation through dynamic mechanical thermal analysis (DMTA). DMTA results showed that the introduction of AO-60 could remarkably improve the damping properties of the composites, including the increase of glass transition temperature (Tg) alongside with the loss factor (tan δ), also indicating the AO-60/ACM(98/100) had the best damping performance amongst the composites which verified by the experimental.

  19. Course Material Model in A&O Learning Environment.

    ERIC Educational Resources Information Center

    Levasma, Jarkko; Nykanen, Ossi

    One of the problematic issues in the content development for learning environments is the process of importing various types of course material into the environment. This paper describes a method for importing material into the A&O open learning environment by introducing a material model for metadata recognized by the environment. The first…

  20. AO/NAO Response to Climate Change. 2; Relative Importance of Low- and High-Latitude Temperature Changes

    NASA Technical Reports Server (NTRS)

    Rind, D.; Perlwitz, J.; Lonergan, P.; Lerner, J.

    2005-01-01

    Using a variety of GCM experiments with various versions of the GISS model, we investigate how different aspects of tropospheric climate changes affect the extratropical Arctic Oscillation (AO)/North Atlantic Oscillation (NAO) circulation indices. The results show that low altitude changes in the extratropical latitudinal temperature gradient can have a strong impact on eddy forcing of the extratropical zonal wind, in the sense that when this latitudinal temperature gradient increases, it helps force a more negative AO/NAO phase. In addition, local conditions at high latitudes can stabilize/destabilize the atmosphere, inducing negative/positive phase changes. To the extent that there is not a large temperature change in the tropical upper troposphere (either through reduced tropical sensitivity at the surface, or limited transport of this change to high levels), the changes in the low level temperature gradient can provide the dominate influence on the extratropical circulation, so that planetary wave meridional refraction and eddy angular momentum transport changes become uncorrelated with potential vorticity transports. In particular, the climate change that produces the most positive NAO phase change would have substantial warming in the tropical upper troposphere over the Pacific Ocean, with high latitude warming in the North Atlantic. An increase in positive phase of these circulation indices is still more likely than not, but it will depend on the degree of tropical and high latitude temperature response and the transport of low level warming into the upper troposphere. These are aspects that currently differ among the models used for predicting the effects of global warning, contributing to the lack of consensus of future changes in the AO/NAO.

  1. AO/NAO Response to Climate Change. 2; Relative Importance of Low- and High-Latitude Temperature Changes

    NASA Technical Reports Server (NTRS)

    Rind, D.; Perlwitz, J.; Lonergan, P.; Lerner, J.

    2005-01-01

    Using a variety of GCM experiments with various versions of the GISS model, we investigate how different aspects of tropospheric climate changes affect the extratropical Arctic Oscillation (AO)/North Atlantic Oscillation (NAO) circulation indices. The results show that low altitude changes in the extratropical latitudinal temperature gradient can have a strong impact on eddy forcing of the extratropical zonal wind, in the sense that when this latitudinal temperature gradient increases, it helps force a more negative AO/NAO phase. In addition, local conditions at high latitudes can stabilize/destabilize the atmosphere, inducing negative/positive phase changes. To the extent that there is not a large temperature change in the tropical upper troposphere (either through reduced tropical sensitivity at the surface, or limited transport of this change to high levels), the changes in the low level temperature gradient can provide the dominate influence on the extratropical circulation, so that planetary wave meridional refraction and eddy angular momentum transport changes become uncorrelated with potential vorticity transports. In particular, the climate change that produces the most positive NAO phase change would have substantial warming in the tropical upper troposphere over the Pacific Ocean, with high latitude warming in the North Atlantic. An increase in positive phase of these circulation indices is still more likely than not, but it will depend on the degree of tropical and high latitude temperature response and the transport of low level warming into the upper troposphere. These are aspects that currently differ among the models used for predicting the effects of global warning, contributing to the lack of consensus of future changes in the AO/NAO.

  2. Transport: Introduction

    NASA Technical Reports Server (NTRS)

    Lewis, William; Rosenberg, Sanders D.

    1992-01-01

    Space transportation requirements for the NASA baseline scenario for future space missions are discussed. Spacecraft/propulsion technologies required for surface-to-orbit, orbit-to-orbit, and surface (lunar) transportation are addressed.

  3. Transport Experiments

    NASA Technical Reports Server (NTRS)

    Hall, Timothy M.; Wuebbles, Donald J.; Boering, Kristie A.; Eckman, Richard S.; Lerner, Jean; Plumb, R. Alan; Rind, David H.; Rinsland, Curtis P.; Waugh, Darryn W.; Wei, Chu-Feng

    1999-01-01

    MM II defined a series of experiments to better understand and characterize model transport and to assess the realism of this transport by comparison to observations. Measurements from aircraft, balloon, and satellite, not yet available at the time of MM I [Prather and Remsberg, 1993], provide new and stringent constraints on model transport, and address the limits of our transport modeling abilities. Simulations of the idealized tracers the age spectrum, and propagating boundary conditions, and conserved HSCT-like emissions probe the relative roles of different model transport mechanisms, while simulations of SF6 and C02 make the connection to observations. Some of the tracers are related, and transport diagnostics such as the mean age can be derived from more than one of the experiments for comparison to observations. The goals of the transport experiments are: (1) To isolate the effects of transport in models from other processes; (2) To assess model transport for realistic tracers (such as SF6 and C02) for comparison to observations; (3) To use certain idealized tracers to isolate model mechanisms and relationships to atmospheric chemical perturbations; (4) To identify strengths and weaknesses of the treatment of transport processes in the models; (5) To relate evaluated shortcomings to aspects of model formulation. The following section are included:Executive Summary, Introduction, Age Spectrum, Observation, Tropical Transport in Models, Global Mean Age in Models, Source-Transport Covariance, HSCT "ANOY" Tracer Distributions, and Summary and Conclusions.

  4. Transport Experiments

    NASA Technical Reports Server (NTRS)

    Hall, Timothy M.; Wuebbles, Donald J.; Boering, Kristie A.; Eckman, Richard S.; Lerner, Jean; Plumb, R. Alan; Rind, David H.; Rinsland, Curtis P.; Waugh, Darryn W.; Wei, Chu-Feng

    1999-01-01

    MM II defined a series of experiments to better understand and characterize model transport and to assess the realism of this transport by comparison to observations. Measurements from aircraft, balloon, and satellite, not yet available at the time of MM I [Prather and Remsberg, 1993], provide new and stringent constraints on model transport, and address the limits of our transport modeling abilities. Simulations of the idealized tracers the age spectrum, and propagating boundary conditions, and conserved HSCT-like emissions probe the relative roles of different model transport mechanisms, while simulations of SF6 and C02 make the connection to observations. Some of the tracers are related, and transport diagnostics such as the mean age can be derived from more than one of the experiments for comparison to observations. The goals of the transport experiments are: (1) To isolate the effects of transport in models from other processes; (2) To assess model transport for realistic tracers (such as SF6 and C02) for comparison to observations; (3) To use certain idealized tracers to isolate model mechanisms and relationships to atmospheric chemical perturbations; (4) To identify strengths and weaknesses of the treatment of transport processes in the models; (5) To relate evaluated shortcomings to aspects of model formulation. The following section are included:Executive Summary, Introduction, Age Spectrum, Observation, Tropical Transport in Models, Global Mean Age in Models, Source-Transport Covariance, HSCT "ANOY" Tracer Distributions, and Summary and Conclusions.

  5. Diffraction limited operation with ARGOS: a hybrid AO system

    NASA Astrophysics Data System (ADS)

    Bonaglia, M.; Busoni, L.; Quirós-Pacheco, F.; Esposito, S.

    2010-07-01

    ARGOS, the Laser Guide Star (LGS) facility of the Large Binocular Telescope (LBT), implements a Ground Layer Adaptive Optics (GLAO) system, using 3 low-altitude beacons, to improve the resolution over the 4'×4' FoV of the imager and Multi Object Spectrograph (MOS) LUCIFER. In this paper we discuss the performance and the reconstruction scheme of an hybrid AO system using the ARGOS Rayleigh beacons complemented with a single faint high-altitude star (NGS or sodium beacon) to sense the turbulence of the upper atmosphere allowing an high degree of on-axis correction. With the ARGOS system, the NGS-upgrade can be immediately implemented at LBT using the already existing Pyramid WFS offering performance similar to the NGS AO system with the advantage of a larger sky coverage.

  6. Real-time control system verification for ELT AO systems

    NASA Astrophysics Data System (ADS)

    Basden, Alastair; Myers, Richard; Morris, Tim; Bharmal, Nazim; Bitenc, Urban; Dipper, Nigel; Reeves, Andrew; Gendron, Eric; Rousset, Gérard; Hubert, Zoltan; Vidal, Fabrice; Matin, Olivier; Gratadour, Damien; Chemla, Fanny

    2013-12-01

    ELT AO systems have demanding computational requirements for real-timecontrol. These systems are required to be fully tested and robustbefore commissioning so that valuable on-sky time is not wasted. Inthis talk I will report recent work at Durham on our ELT AO real-timecontrol system, algorithms that we use to improve robustness, anddevelopment of an end-to-end testing environment that will allow fulltesting of real-time control systems, including both Monte-Carlosimulation and hardware approaches. The talk will include experiencegained with CANARY, how the robustness of this system has beenimproved, and our experience operating with four laser guide stars. Workcarried out in this area on the DRAGON test-bench will also bedescribed.

  7. Intelligent vibration control of ELTs and large AO hardware

    NASA Astrophysics Data System (ADS)

    Pott, J.-U.; Kürster, M.; Trowitzsch, J.; Borelli, J.; Rohloff, R.-R.; Herbst, T.; Böhm, M.; Keck, A.; Ruppel, T.; Sawodny, O.

    2012-07-01

    MPIA leads the construction of the LINC-NIRVANA instrument, the MCAO-supported Fizeau imager for the LBT, serves as pathfinder for future ELT-AO imagers in terms of size and technology. In this contribution, we review recent results and significant progress made on the development of key items of our stratgey to achieve a piston stability of up to 100nm during a science exposure. We present an overview of our vibration control strategies for optical path and tip-tilt stabilization, involving accelerometer based real-time vibration measurements, vibration sensitive active control of actuators, and the development of a dynamical model of the LBT. MPIA also co-develops the E-ELT first-light NIR imager MICADO (both SCAO and MCAO assisted). Our experiences, made with LINC-NIRVANA, will be fed into the MICADO structural AO design to reach highest on-sky sensitivity.

  8. Analysis of Alternatives (AoA) Process Improvement Study

    DTIC Science & Technology

    2016-12-01

    of U.S. Army Training and Doctrine Command (TRADOC) Analysis Center (TRAC’s) AoA Primer and previous acquisition reviews (Decker- Wagner , etc.). (5...2009................................................................36 Figure E-7. Decker- Wagner (Army Acquisition Review) Findings, Jan 2011(1 of 2...37 Figure E-8. Decker- Wagner (Army Acquisition Review) Findings, Jan 2011(2 of 2).................38 Figure E-9. Goldwater Nichols

  9. High-Resolution Imaging of Asteroids/Satellites with AO

    NASA Astrophysics Data System (ADS)

    Merline, William

    2012-02-01

    We propose to make high-resolution observations of asteroids using AO, to measure size, shape, and pole position (spin vectors), and/or to search for satellites. We have demonstrated that AO imaging allows determination of the pole/dimensions in 1 or 2 nights on a single target, rather than the years of observations with lightcurve inversion techniques that only yield poles and axial ratios, not true dimensions. Our new technique (KOALA) combines AO imaging with lightcurve and occultation data for optimum size/shape determinations. We request that LGS be available for faint targets, but using NGS AO, we will measure several large and intermediate asteroids that are favorably placed in spring/summer of 2012 for size/shape/pole. Accurately determining the volume from the often-irregular shape allows us to derive densities to much greater precision in cases where the mass is known, e.g., from the presence of a satellite. We will search several d! ozen asteroids for the presence of satellites, particularly in under-studied populations, particularly NEOs (we have recently achieved the first-ever optical image of an NEO binary [Merline et al. 2008b, IAUC 8977]). Satellites provide a real-life lab for testing collisional models. We will search for satellites around special objects at the request of lightcurve observers, and we will make a search for debris in the vicinity of Pluto, in support of the New Horizons mission. Our shape/size work requires observations over most of a full rotation period (typically several hours).

  10. Propeller Design for Naval Auxiliary AO-177 Jumbo.

    DTIC Science & Technology

    1987-09-01

    Design for Naval Auxiliary AO-177 Jumbo 12 Di -RSONAL AUTHOR(S) Kim, Ki-Han 1 3a TYPE OF REPORT 1,3b TIME COVERED 114 DATE OF REPORT (Year., Month. Day) us...3367 0441 09:11 .1507 .1604 .71 .0442 .1118 .1024 .0906 .0770 OsSO 00000 L3 I 93 S 417 3969 - 3452 -3069 -296 -. 299 to .: -. 039 -. 1612 -. 1424 -. 1304

  11. AO Distal Radius Fracture Classification: Global Perspective on Observer Agreement.

    PubMed

    Jayakumar, Prakash; Teunis, Teun; Giménez, Beatriz Bravo; Verstreken, Frederik; Di Mascio, Livio; Jupiter, Jesse B

    2017-02-01

    Background The primary objective of this study was to test interobserver reliability when classifying fractures by consensus by AO types and groups among a large international group of surgeons. Secondarily, we assessed the difference in inter- and intraobserver agreement of the AO classification in relation to geographical location, level of training, and subspecialty. Methods A randomized set of radiographic and computed tomographic images from a consecutive series of 96 distal radius fractures (DRFs), treated between October 2010 and April 2013, was classified using an electronic web-based portal by an invited group of participants on two occasions. Results Interobserver reliability was substantial when classifying AO type A fractures but fair and moderate for type B and C fractures, respectively. No difference was observed by location, except for an apparent difference between participants from India and Australia classifying type B fractures. No statistically significant associations were observed comparing interobserver agreement by level of training and no differences were shown comparing subspecialties. Intra-rater reproducibility was "substantial" for fracture types and "fair" for fracture groups with no difference accounting for location, training level, or specialty. Conclusion Improved definition of reliability and reproducibility of this classification may be achieved using large international groups of raters, empowering decision making on which system to utilize. Level of Evidence Level III.

  12. Single-shot retinal imaging with AO spectral OCT

    NASA Astrophysics Data System (ADS)

    Zhang, Yan; Rha, Jungtae; Jonnal, Ravi S.; Miller, Donald T.

    2005-04-01

    We demonstrate for the first time an adaptive optics (AO) spectral OCT retina camera that acquires with unprecedented 3D resolution (2.9 μm lateral; 5.5 μm axial) single shot B-scans of the living human retina. The camera centers on a Michelson interferometer that consists of a superluminescent diode for line illuminating the subject's retinal; voice coil translator for controlling the optical path length of the reference channel; and an imaging spectrometer that is cascaded with a 12-bit area CCD array. The imaging spectrometer was designed with negligible off-axis aberrations and was constructed from stock optical components. AO was integrated into the detector channel of the interferometer and dynamically compensated for most of the ocular aberration across a 6 mm pupil. Short bursts of B-scans, with 100 Ascans each, were successfully acquired at 1 msec intervals. Camera sensitivity was found sufficient to detect reflections from all major retinal layers. Individual outer segments of photoreceptors at different retinal eccentricities were observed in vivo. Periodicity of the outer segments matched cone spacing as measured from AO flood illuminated images of the same patches of retina.

  13. LDEF results for polymer matrix composite experiment AO 180

    NASA Technical Reports Server (NTRS)

    Tennyson, R. C.

    1992-01-01

    This report represents a summary of the results obtained to-date on a polymer matrix composite experiment (AO 180) located at station D-12, about 82 deg off the 'ram' direction. Different material systems comprised of graphite, boron, and aramid (Kevlar) fiber reinforcements were studied. Although previous results were presented on in-situ thermal-vacuum cycling effects, particularly dimensional changes associated with outgassing, additional comparative data will be shown from ground-based tests on control and flight samples. The system employed was fully automated for thermal-vacuum cycling using a laser interferometer for monitoring displacements. Erosion of all three classes of materials due to atomic oxygen (AO) will also be discussed, including angle of incidence effects. Data from this experiment will be compared to published results for similar materials in other LDEF experiments. Composite materials' erosion yields will be presented on an AO design nomogram useful for estimating total material loss for given exposure conditions in low Earth orbit (LEO). Optical properties of these materials will also be compared with control samples. A survey of the damage caused by micrometeoroids/debris impacts will be addressed as they relate to polymer matrix composites. Correlations between hole size and damage pattern will be given. Reference to a new nomogram for estimating the number distribution of micrometeoroid/debris impacts for a given space structure as a function of time in LEO will be addressed based on LDEF data.

  14. LDEF results for polymer matrix composite experiment AO 180

    NASA Technical Reports Server (NTRS)

    Tennyson, R. C.

    1992-01-01

    This report represents a summary of the results obtained to-date on a polymer matrix composite experiment (AO 180) located at station D-12, about 82 deg off the 'ram' direction. Different material systems comprised of graphite, boron, and aramid (Kevlar) fiber reinforcements were studied. Although previous results were presented on in-situ thermal-vacuum cycling effects, particularly dimensional changes associated with outgassing, additional comparative data will be shown from ground-based tests on control and flight samples. The system employed was fully automated for thermal-vacuum cycling using a laser interferometer for monitoring displacements. Erosion of all three classes of materials due to atomic oxygen (AO) will also be discussed, including angle of incidence effects. Data from this experiment will be compared to published results for similar materials in other LDEF experiments. Composite materials' erosion yields will be presented on an AO design nomogram useful for estimating total material loss for given exposure conditions in low Earth orbit (LEO). Optical properties of these materials will also be compared with control samples. A survey of the damage caused by micrometeoroids/debris impacts will be addressed as they relate to polymer matrix composites. Correlations between hole size and damage pattern will be given. Reference to a new nomogram for estimating the number distribution of micrometeoroid/debris impacts for a given space structure as a function of time in LEO will be addressed based on LDEF data.

  15. Suppression of Plant Immune Responses by the Pseudomonas savastanoi pv. savastanoi NCPPB 3335 Type III Effector Tyrosine Phosphatases HopAO1 and HopAO2

    PubMed Central

    Castañeda-Ojeda, María Pilar; Moreno-Pérez, Alba; Ramos, Cayo; López-Solanilla, Emilia

    2017-01-01

    The effector repertoire of the olive pathogen P. savastanoi pv. savastanoi NCPPB 3335 includes two members of the HopAO effector family, one of the most diverse T3E families of the P. syringae complex. The study described here explores the phylogeny of these dissimilar members, HopAO1 and HopAO2, among the complex and reveals their activities as immune defense suppressors. Although HopAO1 is predominantly encoded by phylogroup 3 strains isolated from woody organs of woody hosts, both HopAO1 and HopAO2 are phylogenetically clustered according to the woody/herbaceous nature of their host of isolation, suggesting host specialization of the HopAO family across the P. syringae complex. HopAO1 and HopAO2 translocate into plant cells and show hrpL-dependent expression, which allows their classification as actively deployed type III effectors. Our data also show that HopAO1 and HopAO2 possess phosphatase activity, a hallmark of the members of this family. Both of them exert an inhibitory effect on early plant defense responses, such as ROS production and callose deposition, and are able to suppress ETI responses induced by the effectorless polymutant of P. syringae pv. tomato DC3000 (DC3000D28E) in Nicotiana. Moreover, we demonstrate that a ΔhopAO1 mutant of P. savastanoi NCPBB 3335 exhibits a reduced fitness and virulence in olive plants, which supports the relevance of this effector during the interaction of this strain with its host plants. This work contributes to the field with the first report regarding functional analysis of HopAO homologs encoded by P. syringae or P. savastanoi strains isolated from woody hosts. PMID:28529516

  16. Suppression of Plant Immune Responses by the Pseudomonas savastanoi pv. savastanoi NCPPB 3335 Type III Effector Tyrosine Phosphatases HopAO1 and HopAO2.

    PubMed

    Castañeda-Ojeda, María Pilar; Moreno-Pérez, Alba; Ramos, Cayo; López-Solanilla, Emilia

    2017-01-01

    The effector repertoire of the olive pathogen P. savastanoi pv. savastanoi NCPPB 3335 includes two members of the HopAO effector family, one of the most diverse T3E families of the P. syringae complex. The study described here explores the phylogeny of these dissimilar members, HopAO1 and HopAO2, among the complex and reveals their activities as immune defense suppressors. Although HopAO1 is predominantly encoded by phylogroup 3 strains isolated from woody organs of woody hosts, both HopAO1 and HopAO2 are phylogenetically clustered according to the woody/herbaceous nature of their host of isolation, suggesting host specialization of the HopAO family across the P. syringae complex. HopAO1 and HopAO2 translocate into plant cells and show hrpL-dependent expression, which allows their classification as actively deployed type III effectors. Our data also show that HopAO1 and HopAO2 possess phosphatase activity, a hallmark of the members of this family. Both of them exert an inhibitory effect on early plant defense responses, such as ROS production and callose deposition, and are able to suppress ETI responses induced by the effectorless polymutant of P. syringae pv. tomato DC3000 (DC3000D28E) in Nicotiana. Moreover, we demonstrate that a ΔhopAO1 mutant of P. savastanoi NCPBB 3335 exhibits a reduced fitness and virulence in olive plants, which supports the relevance of this effector during the interaction of this strain with its host plants. This work contributes to the field with the first report regarding functional analysis of HopAO homologs encoded by P. syringae or P. savastanoi strains isolated from woody hosts.

  17. SIMS chemical and isotopic analysis of impact features from LDEF experiments AO187-1 and AO187-2

    NASA Technical Reports Server (NTRS)

    Stadermann, Frank J.; Amari, Sachiko; Foote, John; Swan, Pat; Walker, Robert M.; Zinner, Ernst

    1995-01-01

    Previous secondary ion mass spectrometry (SIMS) studies of extended impact features from LDEF capture cell experiment AO187-2 showed that it is possible to distinguish natural and man-made particle impacts based on the chemical composition of projectile residues. The same measurement technique has now been applied to specially prepared gold target impacts from experiment AO187-1 in order to identify the origins of projectiles that left deposits too thin to be analyzed by conventional energy-dispersive x-ray (EDX) spectroscopy. The results indicate that SIMS may be the method of choice for the analysis of impact deposits on a variety of sample surfaces. SIMS was also used to determine the isotopic compositions of impact residues from several natural projectiles. Within the precision of the measurements all analyzed residues show isotopically normal compositions.

  18. Quantum Transport.

    DTIC Science & Technology

    1994-08-15

    Notre Dame was concerned with a variety of quantum transport in mesoscopic structures. This research was funded by the Air Force Office of Scientific...Research under Grant No. AFOSR-91-0211. The major issues examined included quantum transport in high magnetic fields and modulated channels, Coulomb...lifetimes in quasi-1D structures, quantum transport experiments in metals, the mesoscopic photovoltaic effect, and new techniques for fabricating quantum structures in semiconductors.

  19. Apple fruit copper amine oxidase isoforms: peroxisomal MdAO1 prefers diamines as substrates, whereas extracellular MdAO2 exclusively utilizes monoamines.

    PubMed

    Zarei, Adel; Trobacher, Christopher P; Cooke, Alison R; Meyers, Ashley J; Hall, J Christopher; Shelp, Barry J

    2015-01-01

    4-Aminobutyrate (GABA) accumulates in apple fruit during controlled atmosphere storage. A potential source of GABA is the polyamine putrescine, which can be oxidized via copper-containing amine oxidase (CuAO), resulting in the production 4-aminobutanal/Δ(1)-pyrroline, with the consumption of O2 and release of H2O2 and ammonia. Five putative CuAO genes (MdAO genes) were cloned from apple (Malus domestica Borkh. cv. Empire) fruit, and the deduced amino acid sequences found to contain the active sites typically conserved in CuAOs. Genes encoding two of these enzymes, MdAO1 and MdAO2, were highly expressed in apple fruit and selected for further analysis. Amino acid sequence analysis predicted the presence of a C-terminal peroxisomal targeting signal 1 tripeptide in MdAO1 and an N-terminal signal peptide and N-glycosylation site in MdAO2. Transient expression of green fluorescent fusion proteins in Arabidopsis protoplasts or onion epidermal cells revealed a peroxisomal localization for MdAO1 and an extracellular localization for MdAO2. The enzymatic activities of purified recombinant MdAO1 and MdAO2 were measured continuously as H2O2 production using a coupled reaction. MdAO1 did not use monoamines or polyamines and displayed high catalytic efficiency for 1,3-diaminopropane, putrescine and cadaverine, whereas MdAO2 exclusively utilized aliphatic and aromatic monoamines, including 2-phenylethylamine and tyramine. Together, these results indicate that MdAO1 may contribute to GABA production via putrescine oxidation in the peroxisome of apple fruit under controlled atmosphere conditions. MdAO2 seems to be involved in deamination of 2-phenylethylamine, which is a step in the biosynthesis of 2-phenylethanol, a contributor to fruit flavor and flower fragrance. © The Author 2014. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  20. Green FLASH: energy efficient real-time control for AO

    NASA Astrophysics Data System (ADS)

    Gratadour, D.; Dipper, N.; Biasi, R.; Deneux, H.; Bernard, J.; Brule, J.; Dembet, R.; Doucet, N.; Ferreira, F.; Gendron, E.; Laine, M.; Perret, D.; Rousset, G.; Sevin, A.; Bitenc, U.; Geng, D.; Younger, E.; Andrighettoni, M.; Angerer, G.; Patauner, C.; Pescoller, D.; Porta, F.; Dufourcq, G.; Flaischer, A.; Leclere, J.-B.; Nai, A.; Palazzari, P.; Pretet, D.; Rouaud, C.

    2016-07-01

    The main goal of Green Flash is to design and build a prototype for a Real-Time Controller (RTC) targeting the European Extremely Large Telescope (E-ELT) Adaptive Optics (AO) instrumentation. The E-ELT is a 39m diameter telescope to see first light in the early 2020s. To build this critical component of the telescope operations, the astronomical community is facing technical challenges, emerging from the combination of high data transfer bandwidth, low latency and high throughput requirements, similar to the identified critical barriers on the road to Exascale. With Green Flash, we will propose technical solutions, assess these enabling technologies through prototyping and assemble a full scale demonstrator to be validated with a simulator and tested on sky. With this R&D program we aim at feeding the E-ELT AO systems preliminary design studies, led by the selected first-light instruments consortia, with technological validations supporting the designs of their RTC modules. Our strategy is based on a strong interaction between academic and industrial partners. Components specifications and system requirements are derived from the AO application. Industrial partners lead the development of enabling technologies aiming at innovative tailored solutions with potential wide application range. The academic partners provide the missing links in the ecosystem, targeting their application with mainstream solutions. This increases both the value and market opportunities of the developed products. A prototype harboring all the features is used to assess the performance. It also provides the proof of concept for a resilient modular solution to equip a large scale European scientific facility, while containing the development cost by providing opportunities for return on investment.

  1. Identification of system misregistrations during AO-corrected observations

    NASA Astrophysics Data System (ADS)

    Béchet, C.; Thiébaut, É.; .; Tallon, M.; Kolb, J.; Madec, P.-Y.

    2011-09-01

    The E-ELT will be equipped with a deformable mirror inside the telescope. The performance of reconstruction and control depends on the calibration of the interaction matrix- or a model of the interaction matrix- , which characterizes the system and the relationship between the commands sent to the deformable mirrors (DM) and the wavefront sensors (WFS) slopes. Such a calibration will be more complex than for the current systems at the VLT since it will have to be at least partly measured on sky and for a much larger number of degrees of freedom (more than 5000). In addition, gravity or temperature variations for instance are likely to introduce slow evolution of the matching between the M4 Deformable mirror and the WFS geometry. This can occur during observations and therefore degrade the adaptive optics (AO) correction. To relax the need of frequent painful calibrations and to prevent a loss of performance due to misregistrations, we investigate how to track the evolution of the interaction matrix errors in closed-loop without introducing any degradation in the observations. This is done thanks to identification methods and optimization theory. First, we formally describe the problem and the difficulties of such an identification in closed-loop configuration. Then, we present 2 solutions, based on the optimization of the error of estimates of the WFS slopes, at the output of the closed-loop AO. The performance of the methods and their limitations are discussed formally and thanks to numerical simulations of a high order AO system. We finally explore to which extent these methods currently studied for the Adaptive Optics Facility (AOF) at the VLT can be applied to the E-ELT.

  2. Intramedullary locking femoral nails. Experience with the AO nail.

    PubMed Central

    Fogarty, A. B.; Yeates, H. A.

    1991-01-01

    The AO interlocking nail was introduced to the Ulster Hospital, Dundonald in 1988 and since then has been used in over 50 patients with femoral shaft fractures. We have reviewed 45 patients with 46 femoral shaft fractures treated between June 1988 and April 1990. These included four compound fractures and 13 comminuted fractures. The results compare favourably with other series. The union rate was 98% and there were no instances of deep infection. The alternative treatment methods available are discussed along with a review of the relevant literature. Images Fig 3 Fig 5 PMID:1785145

  3. Stream-Field Interactions in the Magnetic Accretor AO Piscium

    NASA Astrophysics Data System (ADS)

    Hellier, Coel; van Zyl, Liza

    2005-06-01

    UV spectra of the magnetic accretor AO Psc show absorption features for half the binary orbit. The absorption is unlike the wind-formed features often seen in similar stars. Instead, we attribute it to a fraction of the stream that overflows the impact with the accretion disk. Rapid velocity variations can be explained by changes in the trajectory of the stream depending on the orientation of the white dwarf's magnetic field. Hence, we are directly observing the interaction of an accretion stream with a rotating field. We compare this behavior to that seen in other intermediate polars and in SW Sex stars.

  4. School Transportation.

    ERIC Educational Resources Information Center

    Executive Educator, 1989

    1989-01-01

    A special report on school transportation covers the following topics: (1) a school bus safety update; (2) equipping school buses with motion detectors; (3) state training requirements for school bus drivers; (4) recruiting and retaining drivers; (5) regulations covering underground fuel-storage tanks; and (6) a transportation directory. (MLF)

  5. Transport Phenomena.

    ERIC Educational Resources Information Center

    McCready, Mark J.; Leighton, David T.

    1987-01-01

    Discusses the problems created in graduate chemical engineering programs when students enter with a wide diversity of understandings of transport phenomena. Describes a two-semester graduate transport course sequence at the University of Notre Dame which focuses on fluid mechanics and heat and mass transfer. (TW)

  6. Transport Phenomena.

    ERIC Educational Resources Information Center

    McCready, Mark J.; Leighton, David T.

    1987-01-01

    Discusses the problems created in graduate chemical engineering programs when students enter with a wide diversity of understandings of transport phenomena. Describes a two-semester graduate transport course sequence at the University of Notre Dame which focuses on fluid mechanics and heat and mass transfer. (TW)

  7. Characterization of Aldehyde Oxidase (AO) Genes Involved in the Accumulation of Carotenoid Pigments in Wheat Grain

    PubMed Central

    Colasuonno, Pasqualina; Marcotuli, Ilaria; Lozito, Maria L.; Simeone, Rosanna; Blanco, Antonio; Gadaleta, Agata

    2017-01-01

    Aldehyde Oxidase (AO) enzyme (EC 1.2.3.1) catalyzes the final steps of carotenoid catabolism and it is a key enzyme in the abscisic acid (ABA) biosynthesis. AO isoforms are located in the cytosolic compartment of tissues in many plants, where induce the oxidation of aldehydes into carboxylic acid, and in addition, catalyze the hydroxylation of some heterocycles. The goal of the present study was to characterize the AO genes involved in the accumulation of carotenoid pigments in wheat grain, an important quantitative trait controlled by multiple genes. The cDNAs corresponding to the four AO isoforms from Arabidopsis thaliana and five AO isoforms from Brachypodium distachyon were used as query in 454 sequence assemblies data for Triticum aestivum cv. Chinese Spring (https://urgi.versailles.inra.fr/blast/blast.php) to obtain the partial or whole orthologous wheat AO sequences. Three wheat isoforms, designated AO1, AO2, and AO3 were located on the chromosome groups 2, 5, and 7, respectively, and mapped on two consensus wheat maps by SNP markers located within the AO gene sequences. To validate the possible relationships between AO3 genes and carotenoid accumulation in wheat, the expression levels of AO-A3 and AO-B3 gene were determined during the kernel maturation stage of two durum wheat cultivars, Ciccio and Svevo, characterized by a low and high carotenoid content, respectively. Different AO-A3 gene expression values were observed between the two cultivars indicating that the AO-A3 allele present in Ciccio was more active in carotenoid degradation. A gene marker was developed and can be used for marker-assisted selection in wheat breeding programs. PMID:28596779

  8. Titanium alloys (AoN) and their involvement in osseointegration

    PubMed Central

    Danza, Matteo; Zollino, Ilaria; Candotto, Valentina; Cura, Francesca; Carinci, Francesco

    2012-01-01

    Background: Osseointegration is essential for a long-term successful and inflammation-free dental implant. Such a result depends on osteoblastic cells growth and differentiation at the tissue-implant interface. The aim of this study was to compare two different AoN titanium layers (GR4 and GR5) to investigate which one had a greater osteoconductive power using human osteoblasts (HOb) culture at two different time-points. Materials and Methods: The expression levels of some bone-related (ALPL, COL1A1, COL3A1, SPP1, RUNX2, and SPARC) were analyzed using real time reverse transcription-polymerase chain reaction (real time RT-PCR). Results: Real-time RT-PCR data showed that after 3 days of treatment with TiA4GR, the genes up-regulated were COL3A1, ALPL, SPP1, and RUNX2. Moreover, no difference in gene expression was noticed 4 days later. On the other hand, the genes that overexpressed after 3 days of treatment with AoN5GR were ALPL, SPP1, and RUNX2. In both cases, the expression of COL1A1 and SPARC was negatively regulated. Conclusion: Our data showed that both titanium surfaces led to osteoblasts recruitment, maturation, and differentiation, thus promoting osseointegration at the tissue-implant interface. PMID:23814585

  9. Titanium alloys (AoN) and their involvement in osseointegration.

    PubMed

    Danza, Matteo; Zollino, Ilaria; Candotto, Valentina; Cura, Francesca; Carinci, Francesco

    2012-12-01

    Osseointegration is essential for a long-term successful and inflammation-free dental implant. Such a result depends on osteoblastic cells growth and differentiation at the tissue-implant interface. The aim of this study was to compare two different AoN titanium layers (GR4 and GR5) to investigate which one had a greater osteoconductive power using human osteoblasts (HOb) culture at two different time-points. The expression levels of some bone-related (ALPL, COL1A1, COL3A1, SPP1, RUNX2, and SPARC) were analyzed using real time reverse transcription-polymerase chain reaction (real time RT-PCR). Real-time RT-PCR data showed that after 3 days of treatment with TiA4GR, the genes up-regulated were COL3A1, ALPL, SPP1, and RUNX2. Moreover, no difference in gene expression was noticed 4 days later. On the other hand, the genes that overexpressed after 3 days of treatment with AoN5GR were ALPL, SPP1, and RUNX2. In both cases, the expression of COL1A1 and SPARC was negatively regulated. Our data showed that both titanium surfaces led to osteoblasts recruitment, maturation, and differentiation, thus promoting osseointegration at the tissue-implant interface.

  10. Illuminating Free-floating Planet Demographics with Keck AO

    NASA Astrophysics Data System (ADS)

    Henderson, Calen B.

    2017-01-01

    The frequency and mass function of free-floating planets (FFPs) are unknown. Gravitational microlensing is able to explore the demographics of FFPs, which are identifiable as short-timescale microlensing events, lasting of-order 1 day for Jupiter-mass planets. In 2011, the MOA ground-based microlensing survey group announced the discovery of an excess of short-timescale microlensing events over what was expected from Galactic models that incorporate stellar densities and kinematics. They account for this excess by positing a population of Jupiter-mass FFPs that outnumbers stars by a ratio of nearly 2:1. However, there are several other possible astrophysical explanations for short-timescale microlensing events, including bound planets on wide orbits and high-velocity stars. Although the specific events identified by MOA lack mass measurements, high-resolution imaging can determine whether the lens systems are luminous, which would exclude the FFP conclusion through proof by contradiction. We have taken H-band adaptive optics (AO) observations of the MOA FFP candidates using NIRC2 on Keck II in order to test this result. Here I will present preliminary results from these AO observations, which will help inform our understanding of the demographics of FFPs.

  11. Studying binary asteroids with NGS and LGS AO systems

    NASA Astrophysics Data System (ADS)

    Marchis, Franck; Berthier, Jerome; Descamps, Pascal; Hestroffer, Daniel; Vachier, Frederic; Laver, Conor; de Pater, Imke; Gavel, Don T.

    2004-10-01

    Since the discovery of Dactyl orbiting around Ida by the Galileo spacecraft in 1993, over twenty-five binary asteroid systems have been discovered using radar, direct imaging and Adaptive Optics observations. Asteroidal moon discoveries dramatically increased with the advent of this last technique on ground based telescopes. Our group focuses on the search and study of double asteroids in the main-belt, in the Trojan population and beyond Neptune's orbit. We have been using several of the AO systems available (Lick-3m, Palomar-5m, VLT-8m, Keck-10m) and related techniques such as Appulse and Laser Guide Star observations to broaden the sample of asteroids observed from the main-belt out to the Kuiper Belt. We will present a quality comparison between various techniques and different AO systems with NGS and will detail our first successful observations with the Lick LGS system. Precise orbital elements of the secondary can be determined by multiple observations spanning large periods of time (several months). Our group developed a method to predict the ephemeris of a secondary companion. Without any assumptions, this method, tested successfully on 22 Kalliope and 121 Hermione binary systems, leads to the direct determination of important physical parameters of the targets, such as their mass and the interior structure, as well as gives direct insights on their formation processes that may be otherwise only be speculated on from spacecraft mission flybys.

  12. Robo-AO: autonomous and replicable laser-adaptive-optics and science system

    NASA Astrophysics Data System (ADS)

    Baranec, C.; Riddle, R.; Ramaprakash, A. N.; Law, N.; Tendulkar, S.; Kulkarni, S.; Dekany, R.; Bui, K.; Davis, J.; Burse, M.; Das, H.; Hildebrandt, S.; Punnadi, S.; Smith, R.

    2012-07-01

    We have created a new autonomous laser-guide-star adaptive-optics (AO) instrument on the 60-inch (1.5-m) telescope at Palomar Observatory called Robo-AO. The instrument enables diffraction-limited resolution observing in the visible and near-infrared with the ability to observe well over one-hundred targets per night due to its fully robotic operation. Robo-AO is being used for AO surveys of targets numbering in the thousands, rapid AO imaging of transient events and long-term AO monitoring not feasible on large diameter telescope systems. We have taken advantage of cost-effective advances in deformable mirror and laser technology while engineering Robo-AO with the intention of cloning the system for other few-meter class telescopes around the world.

  13. Obstetric Transport.

    PubMed

    Scott, Julie

    2016-12-01

    Obstetric transport is a specialized medical transport for maternal, fetal, and neonatal concerns. Perinatal regionalization of care provides a broader geographic availability of obstetric services with defined levels of maternal and neonatal care so that women can be transported to centers with increased resources and capabilities to reduce morbidity and mortality. The Emergency Medical Treatment and Active Labor Act provides regulatory guidance for care of laboring women who require transfer to a higher level of care. The Situation, Background, Assessment, and Recommendation communication can identify key pieces of medical information with recommendations given for mutual expectations of next steps. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Transport Phenomena.

    ERIC Educational Resources Information Center

    Shah, D. B.

    1984-01-01

    Describes a course designed to achieve a balance between exposing students to (1) advanced topics in transport phenomena, pointing out similarities and differences between three transfer processes and (2) common methods of solving differential equations. (JN)

  15. Experience And Results With Preoperatively Shaped AO Mandibular Reconstruction Plates

    NASA Astrophysics Data System (ADS)

    Reuters, Ulrich; Prein, Joachim; Muller, Werner

    1989-04-01

    As a rule continuous bony defects of the mandible after tumour resection are temporarily bridged with the AO reconstruction plate. To precontour the plate, CT-scans of the mandible at a scale of 1:1 6 mm above and parallel to the inferior margin are needed. Corresponding layers further cranial show the anatomy of the chin. Using a lateral cephalograph, the mandibular angle and the length of the plate in the ascending ramus are measured. Of the 19 preshaped reconstruction plates implanted, 11 did not need any intraoperative adjustment of shape. The other 8 plates needed only slight modifications of contour. Preoperative bending of the reconstruction plate reduces the time taken for the operation, protects the material and the plate is precisely shaped.

  16. The 1987 outburst of the BL Lacertid AO 0235 + 164

    NASA Astrophysics Data System (ADS)

    Webb, J. R.; Smith, A. G.

    1989-08-01

    The violently variable BL Lacertid AO 0235 + 164 displayed a 3.24 magnitude outburst in early 1987. This outburst was observed intensively from Rosemary Hill Observatory in three colors. Long term monitoring observations made at Rosemary Hill are examined in an effort to find any recurring timescales associated with this outburst and previous large amplitude outbursts. The energetics of the 1987 outburst are analyzed in terms of the Shields and Wheeler model of a magnetized accretion disk. The timescales identified in the power spectrum (2.8 and 1.6 yr) are input into the model as the storage timescales. Since the emitted energy calculated from the optical burst cannot be stored in a magnetized disk at an allowable radius, it is concluded that either the storage timescales are longer than those identified in the power spectrum, or relativistic beaming effects must be considered, with a Doppler factor of 1.3 to 1.6.

  17. LDEF (Postflight), AO201 : Interplanetary Dust Experiment, Tray H11

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Postflight), AO201 : Interplanetary Dust Experiment, Tray H11 The Interplanetary Dust Experiment hardware has a thin brown stain on the exposed surfaces. A deeper brown stain, probably from the material underneath the small electrical cover plate of the detector frame, can be seen in the upper right corner of some of the detectors. Stain that was seen on the solar sensor base plate in the flight photograph cannot be seen because of reflected light. The colors seen in the detector's mirror like surface are reflections of the surrounding area. A dark spot seen on a detector in the third row from the top in the flight photograph, was not found in a postflight inspection. A close inspection of this photograph does reveal several impact damage locations.

  18. The AO Pediatric Comprehensive Classification of Long Bone Fractures (PCCF)

    PubMed Central

    Joeris, Alexander; Lutz, Nicolas; Blumenthal, Andrea; Slongo, Theddy; Audigé, Laurent

    2017-01-01

    Background and purpose To achieve a common understanding when dealing with long bone fractures in children, the AO Pediatric Comprehensive Classification of Long Bone Fractures (AO PCCF) was introduced in 2007. As part of its final validation, we present the most relevant fracture patterns in the lower extremities of a representative population of children classified according to the PCCF. Patients and methods We included patients up to the age of 17 who were diagnosed with 1 or more long bone fractures between January 2009 and December 2011 at either of 2 tertiary care university hospitals in Switzerland. Patient charts were retrospectively reviewed. Results More lower extremity fractures occurred in boys (62%, n = 341). Of 548 fractured long bones in the lower extremity, 25% involved the femur and 75% the lower leg. The older the patients, the more combined fractures of the tibia and fibula were sustained (adolescents: 50%, 61 of 123). Salter-Harris (SH) fracture patterns represented 66% of single epiphyseal fractures (83 of 126). Overall, 74 of the 83 SH patterns occurred in the distal epiphysis. Of all the metaphyseal fractures, 74 of 79 were classified as incomplete or complete. Complete oblique spiral fractures accounted for 57% of diaphyseal fractures (120 of 211). Of all fractures, 7% (40 of 548) were classified in the category "other", including 29 fractures that were identified as toddler’s fractures. 5 combined lower leg fractures were reported in the proximal metaphysis, 40 in the diaphysis, 26 in the distal metaphysis, and 8 in the distal epiphysis. Interpretation The PCCF allows classification of lower extremity fracture patterns in the clinical setting. Re-introduction of a specific code for toddler’s fractures in the PCCF should be considered. PMID:27882811

  19. The AO Pediatric Comprehensive Classification of Long Bone Fractures (PCCF)

    PubMed Central

    Audigé, Laurent; Slongo, Theddy; Lutz, Nicolas; Blumenthal, Andrea; Joeris, Alexander

    2017-01-01

    Background and purpose The AO Pediatric Comprehensive Classification of Long Bone Fractures (PCCF) describes the localization and morphology of fractures, and considers severity in 2 categories: (1) simple, and (2) multifragmentary. We evaluated simple and multifragmentary fractures in a large consecutive cohort of children diagnosed with long bone fractures in Switzerland. Patients and methods Children and adolescents treated for fractures between 2009 and 2011 at 2 tertiary pediatric surgery hospitals were retrospectively included. Fractures were classified according to the AO PCCF. Severity classes were described according to fracture location, patient age and sex, BMI, and cause of trauma. Results Of all trauma events, 3% (84 of 2,730) were diagnosed with a multifragmentary fracture. This proportion was age-related: 2% of multifragmentary fractures occurred in school­children and 7% occurred in adolescents. In patients diagnosed with a single fracture only, the highest percentage of multifragmentation occurred in the femur (12%, 15 of 123). In fractured paired radius/ulna bones, multifragmentation occurred in 2% (11 of 687); in fractured paired tibia/fibula bones, it occurred in 21% (24 of 115), particularly in schoolchildren (5 of 18) and adolescents (16 of 40). In a multivariable regression model, age, cause of injury, and bone were found to be relevant prognostic factors of multifragmentation (odds ratio (OR) > 2). Interpretation Overall, multifragmentation in long bone fractures in children was rare and was mostly observed in adolescents. The femur was mostly affected in single fractures and the lower leg was mostly affected in paired-bone fractures. The clinical relevance of multifragmentation regarding growth and long-term functional recovery remains to be determined. PMID:27882814

  20. The AO Pediatric Comprehensive Classification of Long Bone Fractures (PCCF)

    PubMed Central

    Joeris, Alexander; Lutz, Nicolas; Blumenthal, Andrea; Slongo, Theddy; Audigé, Laurent

    2017-01-01

    Background and purpose To achieve a common understanding when dealing with long bone fractures in children, the AO Pediatric Comprehensive Classification of Long Bone Fractures (AO PCCF) was introduced in 2007. As part of its final validation, we present the most relevant fracture patterns in the upper extremities of a representative population of children classified according to the PCCF. Patients and methods We included children and adolescents (0–17 years old) diagnosed with 1 or more long bone fractures between January 2009 and December 2011 at the university hospitals in Bern and Lausanne (Switzerland). Patient charts were retrospectively reviewed and fractures were classified from standard radiographs. Results Of 2,292 upper extremity fractures in 2,203 children and adolescents, 26% involved the humerus and 74% involved the forearm. In the humerus, 61%, and in the forearm, 80% of single distal fractures involved the metaphysis. In adolescents, single humerus fractures were more often epiphyseal and diaphyseal fractures, and among adolescents radius fractures were more often epiphyseal fractures than in other age groups. 47% of combined forearm fractures were distal metaphyseal fractures. Only 0.7% of fractures could not be classified within 1 of the child-specific fracture patterns. Of the single epiphyseal fractures, 49% were Salter-Harris type-II (SH II) fractures; of these, 94% occurred in schoolchildren and adolescents. Of the metaphyseal fractures, 58% showed an incomplete fracture pattern. 89% of incomplete fractures affected the distal radius. Of the diaphyseal fractures, 32% were greenstick fractures. 24 Monteggia fractures occurred in pre-school children and schoolchildren, and 2 occurred in adolescents. Interpretation The pattern of pediatric fractures in the upper extremity can be comprehensively described according to the PCCF. Prospective clinical studies are needed to determine its clinical relevance for treatment decisions and prognostication

  1. HST and Keck AO Images of Vortices on Jupiter

    NASA Astrophysics Data System (ADS)

    de Pater, Imke; Wong, M.; Luszcz-Cook, S.; Adamkovics, M.; Marcus, P.; Asay-Davis, X.; Conrad, A.; Go, C.

    2009-09-01

    Observations of Jupiter were conducted in April 2006 and May 2008 with both HST (250-890 nm) and the 10-m Keck telescope. On Keck we used the near-infrared camera NIRC2, coupled to the AO system, at 1.2 to 5 micrometers. At 5 um we are sensitive to Jupiter's thermal emission in cloud-free regions of the atmosphere, while at 1.2 um we see reflected sunlight from hazes and clouds in the troposphere-stratosphere. All small ovals (i.e., all except for Oval BA and the GRS) appear to be surrounded by bright rings at 5 mu, with typical brightness temperatures of 225-250 K, and hence probing depths to 2.5-4 bar. We argue that the small vortices are columnar structures, extending down into the water cloud. Air is rising along the center of these vortices, and descending around the outer periphery; the storm systems are likely fueled by the latent heat released from the water cloud. The descending part of the vertical circulation in the larger ovals is within the ovals, likely at the location of the red ring in Oval BA, which may indicate the maximum radial distance where such return flows can take place. On 19 July 2009, amateur observer Anthony Wesley (Australia) reported a dark spot/streak on Jupiter, near a southern latitude of 56 deg, which he attributed to an impact (analogous to the SL9 impact on Jupiter). We are scheduled to observe Jupiter with the Keck AO system on 24 July 2009 UT; if observations are successful, we will report preliminary results.

  2. The AO Pediatric Comprehensive Classification of Long Bone Fractures (PCCF).

    PubMed

    Joeris, Alexander; Lutz, Nicolas; Blumenthal, Andrea; Slongo, Theddy; Audigé, Laurent

    2017-04-01

    Background and purpose - To achieve a common understanding when dealing with long bone fractures in children, the AO Pediatric Comprehensive Classification of Long Bone Fractures (AO PCCF) was introduced in 2007. As part of its final validation, we present the most relevant fracture patterns in the upper extremities of a representative population of children classified according to the PCCF. Patients and methods - We included children and adolescents (0-17 years old) diagnosed with 1 or more long bone fractures between January 2009 and December 2011 at the university hospitals in Bern and Lausanne (Switzerland). Patient charts were retrospectively reviewed and fractures were classified from standard radiographs. Results - Of 2,292 upper extremity fractures in 2,203 children and adolescents, 26% involved the humerus and 74% involved the forearm. In the humerus, 61%, and in the forearm, 80% of single distal fractures involved the metaphysis. In adolescents, single humerus fractures were more often epiphyseal and diaphyseal fractures, and among adolescents radius fractures were more often epiphyseal fractures than in other age groups. 47% of combined forearm fractures were distal metaphyseal fractures. Only 0.7% of fractures could not be classified within 1 of the child-specific fracture patterns. Of the single epiphyseal fractures, 49% were Salter-Harris type-II (SH II) fractures; of these, 94% occurred in schoolchildren and adolescents. Of the metaphyseal fractures, 58% showed an incomplete fracture pattern. 89% of incomplete fractures affected the distal radius. Of the diaphyseal fractures, 32% were greenstick fractures. 24 Monteggia fractures occurred in pre-school children and schoolchildren, and 2 occurred in adolescents. Interpretation - The pattern of pediatric fractures in the upper extremity can be comprehensively described according to the PCCF. Prospective clinical studies are needed to determine its clinical relevance for treatment decisions and

  3. The AO Pediatric Comprehensive Classification of Long Bone Fractures (PCCF).

    PubMed

    Audigé, Laurent; Slongo, Theddy; Lutz, Nicolas; Blumenthal, Andrea; Joeris, Alexander

    2017-04-01

    Background and purpose - The AO Pediatric Comprehensive Classification of Long Bone Fractures (PCCF) describes the localization and morphology of fractures, and considers severity in 2 categories: (1) simple, and (2) multifragmentary. We evaluated simple and multifragmentary fractures in a large consecutive cohort of children diagnosed with long bone fractures in Switzerland. Patients and methods - Children and adolescents treated for fractures between 2009 and 2011 at 2 tertiary pediatric surgery hospitals were retrospectively included. Fractures were classified according to the AO PCCF. Severity classes were described according to fracture location, patient age and sex, BMI, and cause of trauma. Results - Of all trauma events, 3% (84 of 2,730) were diagnosed with a multifragmentary fracture. This proportion was age-related: 2% of multifragmentary fractures occurred in school-children and 7% occurred in adolescents. In patients diagnosed with a single fracture only, the highest percentage of multifragmentation occurred in the femur (12%, 15 of 123). In fractured paired radius/ulna bones, multifragmentation occurred in 2% (11 of 687); in fractured paired tibia/fibula bones, it occurred in 21% (24 of 115), particularly in schoolchildren (5 of 18) and adolescents (16 of 40). In a multivariable regression model, age, cause of injury, and bone were found to be relevant prognostic factors of multifragmentation (odds ratio (OR) > 2). Interpretation - Overall, multifragmentation in long bone fractures in children was rare and was mostly observed in adolescents. The femur was mostly affected in single fractures and the lower leg was mostly affected in paired-bone fractures. The clinical relevance of multifragmentation regarding growth and long-term functional recovery remains to be determined.

  4. The AO Pediatric Comprehensive Classification of Long Bone Fractures (PCCF).

    PubMed

    Joeris, Alexander; Lutz, Nicolas; Blumenthal, Andrea; Slongo, Theddy; Audigé, Laurent

    2017-04-01

    Background and purpose - To achieve a common understanding when dealing with long bone fractures in children, the AO Pediatric Comprehensive Classification of Long Bone Fractures (AO PCCF) was introduced in 2007. As part of its final validation, we present the most relevant fracture patterns in the lower extremities of a representative population of children classified according to the PCCF. Patients and methods - We included patients up to the age of 17 who were diagnosed with 1 or more long bone fractures between January 2009 and December 2011 at either of 2 tertiary care university hospitals in Switzerland. Patient charts were retrospectively reviewed. Results - More lower extremity fractures occurred in boys (62%, n = 341). Of 548 fractured long bones in the lower extremity, 25% involved the femur and 75% the lower leg. The older the patients, the more combined fractures of the tibia and fibula were sustained (adolescents: 50%, 61 of 123). Salter-Harris (SH) fracture patterns represented 66% of single epiphyseal fractures (83 of 126). Overall, 74 of the 83 SH patterns occurred in the distal epiphysis. Of all the metaphyseal fractures, 74 of 79 were classified as incomplete or complete. Complete oblique spiral fractures accounted for 57% of diaphyseal fractures (120 of 211). Of all fractures, 7% (40 of 548) were classified in the category "other", including 29 fractures that were identified as toddler's fractures. 5 combined lower leg fractures were reported in the proximal metaphysis, 40 in the diaphysis, 26 in the distal metaphysis, and 8 in the distal epiphysis. Interpretation - The PCCF allows classification of lower extremity fracture patterns in the clinical setting. Re-introduction of a specific code for toddler's fractures in the PCCF should be considered.

  5. 76 FR 52972 - United States v. Regal Beloit Corp. and A.O. Smith Corp.; Proposed Final Judgment and Competitive...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-24

    ... acquisition by Regal Beloit Corporation (``RBC'') of the electric motor business of A.O. Smith Corporation... Corporation (``RBC'') and A.O. Smith Corporation (``AOS'') to enjoin RBC's proposed acquisition of the... proposed acquisition of the electric motor business from AOS likely would substantially lessen competition...

  6. Robo-AO KP: A new era in robotic adaptive optics

    NASA Astrophysics Data System (ADS)

    Riddle, Reed L.; Baranec, Christoph; Law, Nicholas M.; Kulkarni, Shrinivas R.; Duev, Dmitry; Ziegler, Carl; Jensen-Clem, Rebecca M.; Atkinson, Dani Eleanor; Tanner, Angelle M.; Zhang, Celia; Ray, Amy

    2016-01-01

    Robo-AO is the first and only fully automated adaptive optics laser guide star AO instrument. It was developed as an instrument for 1-3m robotic telescopes, in order to take advantage of their availability to pursue large survey programs and target of opportunity observations that aren't possible with other AO systems. Robo-AO is currently the most efficient AO system in existence, and it can achieve an observation rate of 20+ science targets per hour. In more than three years of operations at Palomar Observatory, it has been quite successful, producing technology that is being adapted by other AO systems and robotic telescope projects, as well as several high impact scientific publications. Now, Robo-AO has been selected to take over operation of the Kitt Peak National Observatory 2.1m telescope. This will give Robo-AO KP the opportunity to pursue multiple science programs consisting of several thousand targets each during the three years it will be on the telescope. One-sixth of the observing time will be allocated to the US community through the NOAO TAC process. This presentation will discuss the process adapting Robo-AO to the KPNO 2.1m telescope, the plans for integration and initial operations, and the science operations and programs to be pursued.

  7. Pupil Transportation.

    ERIC Educational Resources Information Center

    Bete, Tim, Ed.

    1998-01-01

    Presents the opinions of four transportation experts on issues related to school buses. The experts respond to the following questions: will advertisements placed on buses be used to generate district revenue; will compressed natural gas or liquefied natural gas become standard fuel for school buses; and will school bus seat belts be mandatory and…

  8. Pupil Transportation.

    ERIC Educational Resources Information Center

    Bete, Tim, Ed.

    1998-01-01

    Presents the opinions of four transportation experts on issues related to school buses. The experts respond to the following questions: will advertisements placed on buses be used to generate district revenue; will compressed natural gas or liquefied natural gas become standard fuel for school buses; and will school bus seat belts be mandatory and…

  9. Air transport

    NASA Technical Reports Server (NTRS)

    Page, F Handley

    1924-01-01

    I purpose (sic) in this paper to deal with the development in air transport which has taken place since civil aviation between England and the Continent first started at the end of August 1919. A great deal of attention has been paid in the press to air services of the future, to the detriment of the consideration of results obtained up to the present.

  10. Anomalous transport

    NASA Astrophysics Data System (ADS)

    Cheverry, Christophe

    2017-02-01

    This article is concerned with the relativistic Vlasov equation, for collisionless axisymmetric plasmas immersed in a strong magnetic field, like in tokamaks. It provides a consistent kinetic treatment of the microscopic particle phase-space dynamics. It shows that the turbulent transport can be completely described through WKB expansions.

  11. LDEF (Flight), AO201 : Interplanetary Dust Experiment, Tray G10

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Flight), AO201 : Interplanetary Dust Experiment, Tray G10 The flight/on-orbit photograph of the G10 experi ment tray was taken from the Orbiter aft flight deck during the LDEF retrieval. A light brown stain can be seen on the experiment tray flanges and to a lesser degree on the IDE Chemglaze Z tained their integrity. A light tan stain on the solar sensor base plate, located in the center of the tray, is more easily seen than that on the IDE mounting plate. Surface defects are highly visible due to the lighting conditions existing at the time the photograph was taken. The lighting angle is such that many impact craters can be seen. Two (2) detectors, located in the twenty (20) detector layout in the lower left corner of the tray, seem to have defects. A triangular shaped discoloration appears on the second detector from the left and in the second row from the bottom. Another irregular shaped discoloration can be seen on the fourth detector from the left and in the third row from the bottom. These discolorations appear to be due to material and/or fabrication defects and not reflected light. The blue colors on the detector's mirror like surface are caused by reflections of the LDEF surroundings.

  12. LDEF (Flight), AO038 : Interstellar Gas Experiment, Tray H09

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Flight), AO038 : Interstellar Gas Experiment, Tray H09 The flight photograph of the Interstellar Gas Experiment was taken from the Orbiter aft flight deck during the LDEF retrieval. A very light contamination stain is present on the experiment tray flanges and on the most of the visible LDEF structure. The exception being a darker stain on the structure adjacent to thermal covers that provide venting for the LDEF interior. Both paint dots appear to be heavily coated with the brown contamination stain. The color of the white thermal control paint on the IGE has changed and now varies from off-white to a dark brown. The darker brown areas on the experiment baseplate, around the grid voltage cable connectors, appear to have come from contaminants flowing from inside the LDEF. A dark stain area can be seen on the lower half of the tray's right sidewall but a shadow hides most of the dark stain in the upper left corner of the tray. A lighter stain coats portions of the experiment baseplate and the outside of the canister housing. A beryllium copper collector foil is clearly visible in the lower left canister housing as are the baffles and reflected light from the fine wire mesh grid near the top of the canister housing. Due to an experi- ment system malfunction, the canister collector foils that are visible were exposed for the total mission.

  13. Ruled and holographic experiment (AO 138-5)

    NASA Technical Reports Server (NTRS)

    Bonnemason, Francis

    1993-01-01

    The AO 138-5 experiment was designed, via the FRECOPA (FRench COoperative PAyload) experiment with the aim to study the optical behavior of different diffraction gratings submitted to space vacuum long exposure and solar irradiation. Samples were ruled and holographic gratings, masters or replica, and some additional control mirrors with various coatings. The experiment was located on the B3, trailing edge of the LDEF and was protected against Atomic Oxygen flux. The experienced thermal cycling was evaluated from -23 C to 66 C during the flight, 34,000 orbits. The samples (two batches of four pieces) were located on a dedicated plate, by a pair of equivalent gratings or mirrors; optical faces were located on the external side. The plate was inside a canister, which had been opened in space for ten months. When the satellite returned to Kennedy Space Center, the remaining vacuum in the canister was still correct. The analysis focused on the triple point characterization including light efficiency, wavefront flatness quality and stray light level. Tests were conducted on control mirrors and gratings (rules and holographic master or replica) loaded but not exposed to cosmic dust or direct solar irradiations. They did not show any significant variations. Solar exposure had damaged the coating (aluminum and platinum) reflectivity in the Ultra-Violet region; the degradation is higher with the gratings, in terms of efficiency. However, wavefront flatness quality and stray light level tests revealed no additional changes.

  14. Atomic oxygen effects on LDEF experiment AO171

    NASA Technical Reports Server (NTRS)

    Whitaker, Ann F.; Kamenetzky, Rachel R.; Finckenor, Miria M.; Norwood, Joseph K.

    1993-01-01

    The Solar Array Materials Passive Long Duration Exposure Facility (LDEF) Experiment (SAMPLE), AO171, contained in total approximately 100 materials and materials processes with a 300 specimen complement. With the exception of experiment solar cell and solar cell modules, all test specimens were weighed before flight, thus allowing an accurate determination of mass loss as a result of space exposure. Since almost all of the test specimens were thermal vacuum baked before flight, the mass loss sustained can be attributed principally to atomic oxygen attack. The atomic oxygen effects observed and measured in five classes of materials is documented. The atomic oxygen reactivity values generated for these materials are compared to those values derived for the same materials from exposures on short term shuttle flights. An assessment of the utility of predicting long term atomic oxygen effects from short term exposures is given. This experiment was located on Row 8 position A which allowed all experiment materials to be exposed to an atomic oxygen fluence of 6.93 x 10(exp 21) atoms/cm(sup 2) as a result of being positioned 38 degrees off the RAM direction.

  15. LDEF (Postflight), AO201 : Interplanetary Dust Experiment, Tray G10

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Postflight), AO201 : Interplanetary Dust Experiment, Tray G10 The IDE experiment appears to be in excellent condition in the postflight photograph. All bond joints seem to have survived the space environment and the experiment hardware seems to be intact. The direction and intensity of the artificial light source has caused hot spots and reflections that tend to wash out the brown stain on the exposed surfaces. A close inspection of individual detectors reveal locations where impacts have occurred and damage is present. In the detector layout in the lower left corner of the tray, two detectors continue to show the discolorations observed in the flight photograph. A triangular shape can be seen in the detector located in the second horizontal row from the bottom and the second vertical row from the left. The other detector, located in the third horizontal row from the bottom and the fourth vertical row from the left has an irregular shaped, very faint, discolora tion. The blue color in the detectors metallic surface is caused by reflections of the surrounding area.

  16. Morphogen transport

    PubMed Central

    Müller, Patrick; Rogers, Katherine W.; Yu, Shuizi R.; Brand, Michael; Schier, Alexander F.

    2013-01-01

    The graded distribution of morphogens underlies many of the tissue patterns that form during development. How morphogens disperse from a localized source and how gradients in the target tissue form has been under debate for decades. Recent imaging studies and biophysical measurements have provided evidence for various morphogen transport models ranging from passive mechanisms, such as free or hindered extracellular diffusion, to cell-based dispersal by transcytosis or cytonemes. Here, we analyze these transport models using the morphogens Nodal, fibroblast growth factor and Decapentaplegic as case studies. We propose that most of the available data support the idea that morphogen gradients form by diffusion that is hindered by tortuosity and binding to extracellular molecules. PMID:23533171

  17. MagAO: Status and on-sky performance of the Magellan adaptive optics system

    NASA Astrophysics Data System (ADS)

    Morzinski, Katie M.; Close, Laird M.; Males, Jared R.; Kopon, Derek; Hinz, Phil M.; Esposito, Simone; Riccardi, Armando; Puglisi, Alfio; Pinna, Enrico; Briguglio, Runa; Xompero, Marco; Quirós-Pacheco, Fernando; Bailey, Vanessa; Follette, Katherine B.; Rodigas, T. J.; Wu, Ya-Lin; Arcidiacono, Carmelo; Argomedo, Javier; Busoni, Lorenzo; Hare, Tyson; Uomoto, Alan; Weinberger, Alycia

    2014-07-01

    MagAO is the new adaptive optics system with visible-light and infrared science cameras, located on the 6.5-m Magellan "Clay" telescope at Las Campanas Observatory, Chile. The instrument locks on natural guide stars (NGS) from 0th to 16th R-band magnitude, measures turbulence with a modulating pyramid wavefront sensor binnable from 28×28 to 7×7 subapertures, and uses a 585-actuator adaptive secondary mirror (ASM) to provide at wavefronts to the two science cameras. MagAO is a mutated clone of the similar AO systems at the Large Binocular Telescope (LBT) at Mt. Graham, Arizona. The high-level AO loop controls up to 378 modes and operates at frame rates up to 1000 Hz. The instrument has two science cameras: VisAO operating from 0.5-1μm and Clio2 operating from 1-5 μm. MagAO was installed in 2012 and successfully completed two commissioning runs in 2012-2013. In April 2014 we had our first science run that was open to the general Magellan community. Observers from Arizona, Carnegie, Australia, Harvard, MIT, Michigan, and Chile took observations in collaboration with the MagAO instrument team. Here we describe the MagAO instrument, describe our on-sky performance, and report our status as of summer 2014.

  18. Patterns of Impairments in AOS and Mechanisms of Interaction between Phonological and Phonetic Encoding

    ERIC Educational Resources Information Center

    Laganaro, Marina

    2012-01-01

    Purpose: One reason why the diagnosis of apraxia of speech (AOS) and its underlying impairment are often debated may lie in the fact that most patients do not display pure patterns of AOS. Mixed patterns are clearly acknowledged at other levels of impairment (e.g., lexical-semantic and lexical-phonological), and they have contributed to debate…

  19. SCExAO as a precursor to an ELT exoplanet direct imaging instrument

    NASA Astrophysics Data System (ADS)

    Jovanovic, Nemanja; Guyon, Olivier; Martinache, Frantz; Clergeon, Christophe; Singh, Garima; Vievard, Sebastien; Kudo, Tomoyuki; Garrel, Vincent; Norris, Barnaby; Tuthill, Peter; Stewart, Paul; Huby, Elsa; Perrin, Guy; Lacour, Sylvestre

    2013-12-01

    The Subaru Coronagraphic Extreme AO (SCExAO) instrument consists of a high performance Phase Induced Amplitude Apodisation (PIAA) coronagraph combined with an extreme Adaptive Optics (AO) system operating in the near-infrared (H band). The extreme AO system driven by the 2000 element deformable mirror will allow for Strehl ratios>90% to be achieved in the H-band when it goes closed loop. This makes the SCExAO instrument a powerful platform for high contrast imaging down to angular separations of the order of 1 lambda/D and an ideal testbed for exploring coronagraphic techniques for ELTs. In this paper we report on the recent progress in regards to the development of the instrument, which includes the addition of a visible bench that makes use of the light at shorter wavelengths not currently utilized by SCExAO and closing the loop on the tip/tilt wavefront sensor. We will also discuss several exciting guest instruments which will expand the capabilities of SCExAO over the next few years; namely CHARIS which is a integral field spectrograph as well as VAMPIRES, a visible aperture masking experiment based on polarimetric analysis of circumstellar disks. In addition we will elucidate the unique role extreme AO systems will play in enabling high precision radial velocity spectroscopy for the detection of small companions.

  20. Patterns of Impairments in AOS and Mechanisms of Interaction between Phonological and Phonetic Encoding

    ERIC Educational Resources Information Center

    Laganaro, Marina

    2012-01-01

    Purpose: One reason why the diagnosis of apraxia of speech (AOS) and its underlying impairment are often debated may lie in the fact that most patients do not display pure patterns of AOS. Mixed patterns are clearly acknowledged at other levels of impairment (e.g., lexical-semantic and lexical-phonological), and they have contributed to debate…

  1. Copper transport.

    PubMed

    Linder, M C; Wooten, L; Cerveza, P; Cotton, S; Shulze, R; Lomeli, N

    1998-05-01

    In adult humans, the net absorption of dietary copper is approximately 1 mg/d. Dietary copper joins some 4-5 mg of endogenous copper flowing into the gastrointestinal tract through various digestive juices. Most of this copper returns to the circulation and to the tissues (including liver) that formed them. Much lower amounts of copper flow into and out of other major parts of the body (including heart, skeletal muscle, and brain). Newly absorbed copper is transported to body tissues in two phases, borne primarily by plasma protein carriers (albumin, transcuprein, and ceruloplasmin). In the first phase, copper goes from the intestine to the liver and kidney; in the second phase, copper usually goes from the liver (and perhaps also the kidney) to other organs. Ceruloplasmin plays a role in this second phase. Alternatively, liver copper can also exit via the bile, and in a form that is less easily reabsorbed. Copper is also present in and transported by other body fluids, including those bathing the brain and central nervous system and surrounding the fetus in the amniotic sac. Ceruloplasmin is present in these fluids and may also be involved in copper transport there. The concentrations of copper and ceruloplasmin in milk vary with lactational stage. Parallel changes occur in ceruloplasmin messenger RNA expression in the mammary gland (as determined in pigs). Copper in milk ceruloplasmin appears to be particularly available for absorption, at least in rats.

  2. Multi-conjugate AO for the European Solar Telescope

    NASA Astrophysics Data System (ADS)

    Montilla, I.; Béchet, C.; Le Louarn, M.; Tallon, M.; Sánchez-Capuchino, J.; Collados Vera, M.

    2012-07-01

    The European Solar Telescope (EST) will be a 4-meter diameter world-class facility, optimized for studies of the magnetic coupling between the deep photosphere and upper chromosphere. It will specialize in high spatial resolution observations and therefore it has been designed to incorporate an innovative built-in Multi-Conjugate Adaptive Optics system (MCAO). It combines a narrow field high order sensor that will provide the information to correct the ground layer and a wide field low order sensor for the high altitude mirrors used in the MCAO mode. One of the challenging particularities of solar AO is that it has to be able to correct the turbulence for a wide range of observing elevations, from zenith to almost horizon. Also, seeing is usually worse at day-time, and most science is done at visible wavelengths. Therefore, the system has to include a large number of high altitude deformable mirrors. In the case of the EST, an arrangement of 4 high altitude DMs is used. Controlling such a number of mirrors makes it necessary to use fast reconstruction algorithms to deal with such large amount of degrees of freedom. For this reason, we have studied the performance of the Fractal Iterative Method (FriM) and the Fourier Transform Reconstructor (FTR), to the EST MCAO case. Using OCTOPUS, the end-to-end simulator of the European Southern Observatory, we have performed several simulations with both algorithms, being able to reach the science requirement of a homogeneous Strehl higher that 50% all over the 1 arcmin field of view.

  3. LDEF (Postflight), AO038 : Interstellar Gas Experiment, Tray H06

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Postflight), AO038 : Interstellar Gas Experiment, Tray H06 The post landing photograph was taken from the Orbiter's cargo bay access hatch during post landing operations to prepare the Orbiter for the ferry flight from the Dryden Flight Research Center to the Kennedy Space Center. A very light contamination stain is present on the experiment tray flanges and on the most of the visible LDEF structure. The exception being a much darker stain on the structure adjacent to thermal covers that provide venting for the LDEF interior. The paint dot adjacent to the thermal cover vent area is heavily coated with the brown contamination stain while the paint dot adjacent to the center end cover plate has a very light coating. The color of the white thermal control paint on the IGE has changed and now varies from offwhite to a dark brown. The darker brown areas on the experiment baseplate, around the grid voltage cable connectors, appear to have come from contaminants flowing from inside the LDEF. A dark stain area can be seen on the tray's lower sidewall and in the upper left corner of the tray. A lighter stain coats portions of the experiment baseplate and the outside of the canister housing. A beryllium copper collector foil is clearly visible within the canister housings as are the baffles and reflected light from the fine wire mesh grid near the top of the canister housing. Due to an experi- ment system malfunction, the canister collector foils that are visible were exposed for the total mission.

  4. LDEF (Postflight), AO201 : Interplanetary Dust Experiment, Tray B12

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Postflight), AO201 : Interplanetary Dust Experiment, Tray B12 The postflight photograph shows little change of the exposed surfaces when compared with the prelaunch photograph. Although not noticable in the photograph, a light coating of contamination was seen on all experiment surfaces in this location. The difference in colors of the IDE detectors, located on the right hand mounting plate, is a result of the reflected surroundings and not related to space exposure. A close observation of the detector surfaces reveal that some damage has occured from meteroid and/or debris impacts. One impact crater can be seen, upper right quadrant, on the detector located in the sixth (6th) row down from the top and the fifth (5th) row from the right. Other impacts, smaller in size, show as small white dots on the detector surface. The solar sensor seems to have changed little, if any. However, the color of the solar array baseplate, showing indications of contamination, appears to be darker than the detector mounting plate. The center section cover plate shows little change when compared with the pre-launch photograph. However, during inspection, a light coat of the brown contamination has been observed on all surfaces. The color of the bonding material (RTV) used to secure several thin specimen, sapphire, to individual mounting plates has changed from pink to gold. At one location, that of a single specimen, the bonding material is more gray than gold in color. This has been attributed to the specimen being considerably thicker. The EPDS thermal cover in the right hand side of the tray shows a light coating of brown contamination on the Chemglaze II A-276 white paint.

  5. GLAS/NAOMI: ground-layer AO at the William Herschel Telescope

    NASA Astrophysics Data System (ADS)

    Benn, Chris; Abrams, Don; Agocs, Tibor; Cano, Diego; Gregory, Tom; Guerra, Juan Carlos; Martin, Olivier; Morris, Tim; Myers, Richard; Rix, Samantha; Rutten, Rene; Skillen, Ian; Skvarč, Jure; Tulloch, Simon

    2008-07-01

    GLAS is an upgrade of the William Herschel Telescope's existing natural-guide-star (NGS) AO system NAOMI to incorporate a 20-W Rayleigh laser guide star (LGS) projected to an altitude of 15 km. It is currently being commissioned on-sky, and we review here the current status of the project. GLAS/NAOMI delivers dramatic improvements in PSF in both the near-IR (AO-corrected FWHM close to the diffraction limit, >~ 0.15 arcsec) and in the optical (factor of ~ 2 reduction in FWHM). The performance is similar to that with NGS, and is consistent with predictions from modelling. The main advantage over NGS AO is the large gain in sky coverage (from ~ 1% to ~ 100% at galactic latitude 40°). GLAS provides the first on-sky demonstration of closed-loop ground-layer AO (GLAO), and is the first Rayleigh LGS AO system to be offered for general use, at any telescope.

  6. Lick Observatory's Shane telescope adaptive optics system (ShaneAO): research directions and progress

    NASA Astrophysics Data System (ADS)

    Gavel, Donald T.; Kupke, Renate; Rudy, Alexander R.; Srinath, Srikar; Dillon, Daren; Poyneer, Lisa A.

    2016-07-01

    We present a review of the ongoing research activity surrounding the adaptive optics system at the Shane telescope (ShaneAO) particularly the R&D efforts on the technology and algorithms for that will advance AO into wider application for astronomy. We are pursuing the AO challenges for whole sky coverage diffraction-limited correction down to visible science wavelengths. This demands high-order wavefront correction and bright artificial laser beacons. We present recent advancements in the development of MEMS based AO correction, woofer-tweeter architecture, wind-predictive wavefront control algorithms, atmospheric characterization, and a pulsed fiber amplifier guide star laser tuned for optical pumping of the sodium layer. We present the latest on-sky results from the new AO system and present status and experimental plans for the optical pumping guide star laser.

  7. AO-308: the high-order adaptive optics system at Big Bear Solar Observatory

    NASA Astrophysics Data System (ADS)

    Shumko, Sergey; Gorceix, Nicolas; Choi, Seonghwan; Kellerer, Aglaé; Cao, Wenda; Goode, Philip R.; Abramenko, Volodymyr; Richards, Kit; Rimmele, Thomas R.; Marino, Jose

    2014-08-01

    In this paper we present Big Bear Solar Observatory's (BBSO) newest adaptive optics system - AO-308. AO-308 is a result of collaboration between BBSO and National Solar Observatory (NSO). AO-308 uses a 357 actuators deformable mirror (DM) from Xinetics and its wave front sensor (WFS) has 308 sub-apertures. The WFS uses a Phantom V7.3 camera which runs at 2000 Hz with the region of interest of 416×400 pixels. AO-308 utilizes digital signal processors (DSPs) for image processing. AO-308 has been successfully used during the 2013 observing season. The system can correct up to 310 modes providing diffraction limited images at all wavelengths of interest.

  8. Robo-AO: Initial results from the first autonomous laser guide star adaptive optics instrument

    NASA Astrophysics Data System (ADS)

    Riddle, R. L.; Baranec, C.; Law, N. M.; Ramaprakash, A. N.; Tendulkar, S.; Hogstrom, K.; Bui, K.; Burse, M.; Chordia, P.; Das, H.; Dekany, R.; Kulkarni, S.; Punnadi, S.; Smith, R.

    2014-12-01

    Large surveys are discovering thousands of objects which require further characterization at high angular resolution. The demands on space-based observatories and large telescopes with AO systems leave them generally unavailable for large high angular resolution surveys. To address this gap, we have developed Robo-AO, the first robotic laser AO system, as an economical and efficient imaging instrument for 1-3 m class telescopes. Observations of over 200 stellar objects per night have routinely been performed, with target-to-target observation overheads of less than 1.5 minutes. Scientific programs of several thousands of targets can be executed in mere weeks, and Robo-AO has already completed the three largest AO surveys to date.

  9. Bringing the Visible Universe into Focus with Robo-AO

    NASA Astrophysics Data System (ADS)

    Baranec, Christoph; Riddle, Reed; Law, Nicholas M.; Ramaprakash, A. N.; Tendulkar, Shriharsh P.; Bui, Khanh; Burse, Mahesh P.; Chordia, Pravin; Das, Hillol K.; Davis, Jack T. C.; Dekany, Richard G.; Kasliwal, Mansi M.; Kulkarni, Shrinivas R.; Morton, Timothy D.; Ofek, Eran O.; Punnadi, Sujit

    2013-02-01

    focus a high-power laser beam in the direction of the astronomical target to create an artificial reference of known shape, also known as a 'laser guide star'. The Robo-AO laser adaptive optics system employs a 10-W ultraviolet laser focused at a distance of 10 km to generate a laser guide star. Wavefront sensor measurements of the laser guide star drive the adaptive optics correction resulting in diffraction-limited images that have an angular resolution of ~0.1 arc seconds on a 1.5-m telescope.

  10. Bringing the visible universe into focus with Robo-AO.

    PubMed

    Baranec, Christoph; Riddle, Reed; Law, Nicholas M; Ramaprakash, A N; Tendulkar, Shriharsh P; Bui, Khanh; Burse, Mahesh P; Chordia, Pravin; Das, Hillol K; Davis, Jack T C; Dekany, Richard G; Kasliwal, Mansi M; Kulkarni, Shrinivas R; Morton, Timothy D; Ofek, Eran O; Punnadi, Sujit

    2013-02-12

    a high-power laser beam in the direction of the astronomical target to create an artificial reference of known shape, also known as a 'laser guide star'. The Robo-AO laser adaptive optics system, employs a 10-W ultraviolet laser focused at a distance of 10 km to generate a laser guide star. Wavefront sensor measurements of the laser guide star drive the adaptive optics correction resulting in diffraction-limited images that have an angular resolution of ~0.1 arc seconds on a 1.5-m telescope.

  11. Bringing the Visible Universe into Focus with Robo-AO

    PubMed Central

    Baranec, Christoph; Riddle, Reed; Law, Nicholas M.; Ramaprakash, A.N.; Tendulkar, Shriharsh P.; Bui, Khanh; Burse, Mahesh P.; Chordia, Pravin; Das, Hillol K.; Davis, Jack T.C.; Dekany, Richard G.; Kasliwal, Mansi M.; Kulkarni, Shrinivas R.; Morton, Timothy D.; Ofek, Eran O.; Punnadi, Sujit

    2013-01-01

    focus a high-power laser beam in the direction of the astronomical target to create an artificial reference of known shape, also known as a 'laser guide star'. The Robo-AO laser adaptive optics system2,3 employs a 10-W ultraviolet laser focused at a distance of 10 km to generate a laser guide star. Wavefront sensor measurements of the laser guide star drive the adaptive optics correction resulting in diffraction-limited images that have an angular resolution of ~0.1 arc seconds on a 1.5-m telescope. PMID:23426078

  12. -----SPACE TRANSPORTATION

    NASA Image and Video Library

    1998-10-07

    This photograph depicts an air-breathing rocket engine prototype in the test bay at the General Applied Science Lab facility in Ronkonkoma, New York. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced Space Transportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  13. Mobile Transporter

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The Space Shuttle Atlantis, STS-110 mission, deployed this railcar, called the Mobile Transporter, and an initial 43-foot section of track, the S0 (S-zero) truss, preparing the International Space Station (ISS) for future spacewalks. The first railroad in space, the Mobile Transporter will allow the Station's robotic arm to travel up and down the finished truss for future assembly and maintenance. The 27,000-pound S0 truss is the first of 9 segments that will make up the Station's external framework that will eventually stretch 356 feet (109 meters), or approximately the length of a football field. The completed truss structure will hold solar arrays and radiators to provide power and cooling for additional international research laboratories from Japan and Europe that will be attached to the Station. The Space Shuttle Orbiter Atlantis, STS-110 mission, was launched April 8, 2002 and returned to Earth April 19, 2002. STS-110's Extravehicular Activity (EVA) marked the first use of the Station's robotic arm to maneuver spacewalkers around the Station.

  14. Proton Transport

    NASA Technical Reports Server (NTRS)

    Pohorille, Andrew; DeVincenzi, Donald L. (Technical Monitor)

    2001-01-01

    The transport of protons across membranes is an essential process for both bioenergetics of modern cells and the origins of cellular life. All living systems make use of proton gradients across cell walls to convert environmental energy into a high-energy chemical compound, adenosine triphosphate (ATP), synthesized from adenosine diphosphate. ATP, in turn, is used as a source of energy to drive many cellular reactions. The ubiquity of this process in biology suggests that even the earliest cellular systems were relying on proton gradient for harvesting environmental energy needed to support their survival and growth. In contemporary cells, proton transfer is assisted by large, complex proteins embedded in membranes. The issue addressed in this Study was: how the same process can be accomplished with the aid of similar but much simpler molecules that could have existed in the protobiological milieu? The model system used in the study contained a bilayer membrane made of phospholipid, dimyristoylphosphatidylcholine (DMPC) which is a good model of the biological membranes forming cellular boundaries. Both sides of the bilayer were surrounded by water which simulated the environment inside and outside the cell. Embedded in the membrane was a fragment of the Influenza-A M$_2$ protein and enough sodium counterions to maintain system neutrality. This protein has been shown to exhibit remarkably high rates of proton transport and, therefore, is an excellent model to study the formation of proton gradients across membranes. The Influenza M$_2$ protein is 97 amino acids in length, but a fragment 25 amino acids long. which contains a transmembrane domain of 19 amino acids flanked by three amino acids on each side. is sufficient to transport protons. Four identical protein fragments, each folded into a helix, aggregate to form small channels spanning the membrane. Protons are conducted through a narrow pore in the middle of the channel in response to applied voltage. This

  15. Robo-AO: The First Autonomous Laser Guide Star Adaptive Optics System for Small Telescopes

    NASA Astrophysics Data System (ADS)

    Riddle, Reed L.; Baranec, C.; Ramaprakash, A. N.; Law, N.; Tendulkar, S.; Kulkarni, S.; Bui, K.; Burse, M.; Chordia, P.; Das, H.; Dekany, R.; Kasliwal, M.; Ofek, E.; Zolkower, J.

    2011-01-01

    Robo-AO will be the first fully autonomous laser guide star adaptive optics and science system. Specifically designed to take advantage of small (1 to 3 meter) telescopes, Robo-AO will deliver high angular resolution science in the visible and near infrared for up to hundreds of targets per night. This will enable the exploration of science programs not practical for larger aperture adaptive optics systems. This presentation discusses the current status of the Robo-AO project, including the laboratory testbed, laser guide star facility and plans for a demonstration of the fully autonomous system next year.

  16. Vibrations in MagAO: resonance sources identification and first approaches for modeling and control

    NASA Astrophysics Data System (ADS)

    Garcés, Javier; Zúñiga, Sebastián.; Close, Laird; Males, Jared; Morzinski, Katie; Escárate, Pedro; Castro, Mario; Marchioni, José; Rojas, Diego

    2016-07-01

    The Magellan Telescope Adaptive Optics System (MagAO) is subject to resonance effects induced by elements within the system instrumentation, such as fans and cooling pumps. Normalized PSDs are obtained through frequency-based analysis of closed-loop on-sky data, detecting and measuring vibration effects. Subsequently, a space-state model for the AO loop is obtained, using a standard AO loop scheme with an integrator-based controller and including the vibration effects as disturbances. Finally, a new control alternative is proposed, focusing on residual phase variance minimization through the design and simulation of an optimal LQG control approach.

  17. -----SPACE TRANSPORTATION

    NASA Image and Video Library

    2000-05-01

    This photograph depicts an air-breathing rocket engine that completed an hour or 3,600 seconds of testing at the General Applied Sciences Laboratory in Ronkonkoma, New York. Referred to as ARGO by its design team, the engine is named after the mythological Greek ship that bore Jason and the Argonauts on their epic voyage of discovery. Air-breathing engines, known as rocket based, combined-cycle engines, get their initial take-off power from specially designed rockets, called air-augmented rockets, that boost performance about 15 percent over conventional rockets. When the vehicle's velocity reaches twice the speed of sound, the rockets are turned off and the engine relies totally on oxygen in the atmosphere to burn hydrogen fuel, as opposed to a rocket that must carry its own oxygen, thus reducing weight and flight costs. Once the vehicle has accelerated to about 10 times the speed of sound, the engine converts to a conventional rocket-powered system to propel the craft into orbit or sustain it to suborbital flight speed. NASA's Advanced SpaceTransportation Program at Marshall Space Flight Center, along with several industry partners and collegiate forces, is developing this technology to make space transportation affordable for everyone from business travelers to tourists. The goal is to reduce launch costs from today's price tag of $10,000 per pound to only hundreds of dollars per pound. NASA's series of hypersonic flight demonstrators currently include three air-breathing vehicles: the X-43A, X-43B and X-43C.

  18. LDEF (Prelaunch), AO201 : Interplanetary Dust Experiment, Tray B12

    NASA Technical Reports Server (NTRS)

    1984-01-01

    LDEF (Prelaunch), AO201 : Interplanetary Dust Experiment, Tray B12 The prelaunch photograph shows the six (6) inch deep Interplanetary Dust Experiment (IDE) master control tray. The tray has three (3) mounting/cover plates elevated on fiberglass stand-offs to provide clearance and protection for hardware and electronics located underneath. The stand-offs also raise the plates to a level that minimizes shading of detectors by the tray sidewalls. The mounting plate located at the left hand end of the tray is populated with eighty (80) metaloxide-silicon (MOS) capacitor-type impact sensors and one (1) solar sensor that is located approximately in the center of the mounting plate. The IDE sensors are two (2) inch diameter MOS capacitor structures approximately 250 um thick. The detectors are formed by growing either 0.4um or 1.0um thick silicon oxide, SiO2, layer on the 250um thick, B-doped polished silicon wafer. The top metal contact, the visible surface, was formed by vapor deposition of 1000A of aluminum on the SiO2 surface. Aluminum was also vapor deposited on the backside to form the contact with the silicon substrate. Gold wires are bonded to the front and back aluminum layers for use in connecting the detectors to the circuits. The complete wafers, IDE detectors, are mounted on chromic anodized aluminum frames by bonding the detector backside to the aluminum frame with a space qualified RTV silicon adhesive, de-volatized RTV-511. The difference in colors of the detectors is caused by reflections in the metallized surfaces. A reflection of one of the technicians is visible in the three (3) rows of detector on the left hand side of the mounting plate. The solar sensor, located at the mounting plate center, consist of four (4) silicon solar cells connected in series and associated circuity bonded to an aluminum baseplate. The solar sensor registered each orbital sunrise independant of LDEF orientation at the time of sunrise. When IDE solar sensor data from the six

  19. Closeup of CO172AO8, showing section of building 211 closest to ...

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

    Close-up of CO-172-AO-8, showing section of building 211 closest to building 206. - Fitzsimons General Hospital, Quartermaster's Storehouse, Southwest Corner of East I Avenue & North Twelfth Street, Aurora, Adams County, CO

  20. Robo-AO: An Autonomous Laser Adaptive Optics and Science System

    NASA Astrophysics Data System (ADS)

    Baranec, Christoph; Riddle, Reed; Ramaprakash, A. N.; Law, Nicholas; Tendulkar, Shriharsh; Kulkarni, Shrinivas; Dekany, Richard; Bui, Khanh; Davis, Jack; Zolkower, Jeff; Fucik, Jason; Burse, Mahesh; Das, Hillol; Chordia, Pravin; Kasliwal, Mansi; Ofek, Eran; Morton, Timothy; Johnson, John

    2011-07-01

    Robo-AO, a fully autonomous, laser guide star adaptive optics and science system, is being commissioned at Palomar Observatory's 60-inch telescope. Here we discuss the instrument, scientific goals and results of initial on-sky operation.

  1. Te Ao Kori as Expressive Movement in Aotearoa New Zealand Physical Education Teacher Education (PETE): A Narrative Account

    ERIC Educational Resources Information Center

    Legge, Maureen

    2011-01-01

    A unique aspect of Aotearoa/New Zealand physical education is the inclusion of Maori culture in the form of te ao kori. Te ao kori translates to mean the world of movement and is represented by the interpretation of indigenous movement, games and pastimes. Participation in te ao kori means the sports-based normative frame of reference for physical…

  2. VizieR Online Data Catalog: Robo-AO Kepler planetary candidate survey. II. (Baranec+, 2016)

    NASA Astrophysics Data System (ADS)

    Baranec, C.; Ziegler, C.; Law, N. M.; Morton, T.; Riddle, R.; Atkinson, D.; Schonhut, J.; Crepp, J.

    2016-10-01

    We selected targets that we had not previously observed from the KOI Catalog based on the Q1-Q12 Kepler data (Rowe et al. 2015, Cat. J/ApJS/217/16). These targets were added to the Robo-AO intelligent observing queue and observed during the summer of 2013. We obtained high angular resolution images of 956 Kepler planet candidate host stars with the Robo-AO robotic laser AOs system over the course of 19 nights between 2013 July 21 and 2013 October 25, detailed in Table5. We also include 13 images from 2012 (2012 July 16-September 13) that required additional confirmation of the KOI position in the Robo-AO field of view. All the observations were performed in a queue-scheduled mode in combination with other science programs using the Robo-AO autonomous laser AO system mounted on the robotic 1.5m telescope at Palomar Observatory (exposure time: 90s; observation wavelengths: 600-950nm; FWHM resolution: 0.12''-0.15''; field of view: 44''*44''; pixel scale: 43.1mas/pix; detector format: 10242 pixels; targets observed/hour: 20). We obtained images of 50 KOIs with the NIRC2 instrument behind the Keck II AO system that were previously observed with Robo-AO and had evidence of a companion. Observations were conducted on 2013 June 25, 2013 August 24 and 25, 2014 August 17, and 2015 July 25 in the K, Ks, or Kp filters, and in the narrow mode of NIRC2 (9.952mas/pixel). (4 data files).

  3. Thin glass shells for AO: from plano to off-axis aspherics

    NASA Astrophysics Data System (ADS)

    Harel, Emmanuelle; Anretar, Alain; Antelme, Jean-Pierre; Caillon, Stéphane; Dussourd, Adrien; Foucaud, Guillaume; Jaury, Hervé; Roure, Océane; William, Jean-Philippe; Wuillaume, Philippe; Ruch, Eric; Geyl, Roland

    2016-07-01

    Reosc has been working on thin glass shells for many years and was recently selected by ESO for the production of the E-ELT M4 mirror thin glass shells. Previously Reosc also produced the aspheric thin shell for the VLT-M2 AO Facility. Based on this experience we will discuss how off axis thin glass shells can be made for the next generation AO systems like the GMT one.

  4. East Asian winter temperature variation associated with the combined effects of AO and WP pattern

    NASA Astrophysics Data System (ADS)

    Park, Hye-Jin; Ahn, Joong-Bae

    2016-04-01

    The combined effects of the Arctic Oscillation (AO) and Western Pacific (WP) teleconnection pattern on the East Asian winter monsoon (EAWM) over the last 56 years (1958/59-2013/2014) were investigated using NCEP/NCAR reanalysis data (Park and Ahn, 2015). The study results revealed that the effect of the AO on winter temperature in East Asia could be changed depending on the phases of the WP pattern in the North Pacific. The negative relationship between the EAWM and the AO increased when the AO and WP were in-phase with each other. Hence, when winter negative (positive) AO was accompanied by negative (positive) WP, negative (positive) temperature anomalies were dominant across the entire East Asia region. Conversely, when the AO and WP were of-of-phase, the winter temperature anomaly in East Asia did not show distinct changes. Furthermore, from the perspective of stationary planetary waves, the zonal wavenumber-2 patterns of sea level pressure and geopotential height at 500hPa circulation strengthened when the AO and WP were in-phase but were not significant for the out-of-phase condition. It explained the possible mechanism of the combined effects of the AO and WP on the circulation related to EAWM. Reference Park, H.-J., and J.-B. Ahn (2015) Combined effect of the Arctic Oscillation and the Western Pacific pattern on East Asia winter temperature, Clim. Dyn. DOI:10.1007/s00382-015-2763-2. Acknowledgements This work was funded by the Korea Meteorological Administration Research and Development Program under grant KMIPA2015-2081.

  5. OPERA, an automatic PSF reconstruction software for Shack-Hartmann AO systems: application to Altair

    NASA Astrophysics Data System (ADS)

    Jolissaint, Laurent; Veran, Jean-Pierre; Marino, Jose

    2004-10-01

    When doing high angular resolution imaging with adaptive optics (AO), it is of crucial importance to have an accurate knowledge of the point spread function associated with each observation. Applications are numerous: image contrast enhancement by deconvolution, improved photometry and astrometry, as well as real time AO performance evaluation. In this paper, we present our work on automatic PSF reconstruction based on control loop data, acquired simultaneously with the observation. This problem has already been solved for curvature AO systems. To adapt this method to another type of WFS, a specific analytical noise propagation model must be established. For the Shack-Hartmann WFS, we are able to derive a very accurate estimate of the noise on each slope measurement, based on the covariances of the WFS CCD pixel values in the corresponding sub-aperture. These covariances can be either derived off-line from telemetry data, or calculated by the AO computer during the acquisition. We present improved methods to determine 1) r0 from the DM drive commands, which includes an estimation of the outer scale L0 2) the contribution of the high spatial frequency component of the turbulent phase, which is not corrected by the AO system and is scaled by r0. This new method has been implemented in an IDL-based software called OPERA (Performance of Adaptive Optics). We have tested OPERA on Altair, the recently commissioned Gemini-North AO system, and present our preliminary results. We also summarize the AO data required to run OPERA on any other AO system.

  6. Robo-AO: Initial results from the first autonomous laser guide star adaptive optics instrument

    NASA Astrophysics Data System (ADS)

    Riddle, R.; Baranec, C.; Law, N. M.; Ramaprakash, A. N.; Tendulkar, S.; Hogstrom, K.; Bui, K.; Burse, M.; Chordia, P.; Das, H.; Dekany, R.; Kulkarni, S.; Punnadi, S.; Smith, R.

    2014-03-01

    Large surveys, such as the Kepler mission and Palomar Transient Factory, are discovering upwards of thousands of objects which require further characterization at angular resolutions significantly finer than normally allowed by atmospheric seeing. The demands on precious space-based observatories (i.e. Hubble Space Telescope) and large telescopes with adaptive optics (AO) systems (i.e. Keck, VLT, Gemini) leave them generally unavailable for high angular resolution surveys of more than a few hundred targets at a time. To address the gap between scientific objects and available telescopes, we have developed Robo-AO, the first robotic laser AO system, as an economical and efficient imaging instrument for the more readily available 1-3 m class telescopes. The Robo-AO system system demonstrates angular resolutions approaching the visible diffraction limit of the Palomar 60-inch telescope. Observations of over 200 stellar objects per night have routinely been performed, with target-to-target observation overheads of less than 1.5 minutes. Scientific programs requiring high-resolution follow-up characterization of several thousands of targets can thus be executed in mere weeks, and Robo-AO has already completed the three largest AO surveys to date.

  7. Robotic transportation.

    PubMed

    Lob, W S

    1990-09-01

    Mobile robots perform fetch-and-carry tasks autonomously. An intelligent, sensor-equipped mobile robot does not require dedicated pathways or extensive facility modification. In the hospital, mobile robots can be used to carry specimens, pharmaceuticals, meals, etc. between supply centers, patient areas, and laboratories. The HelpMate (Transitions Research Corp.) mobile robot was developed specifically for hospital environments. To reach a desired destination, Help-Mate navigates with an on-board computer that continuously polls a suite of sensors, matches the sensor data against a pre-programmed map of the environment, and issues drive commands and path corrections. A sender operates the robot with a user-friendly menu that prompts for payload insertion and desired destination(s). Upon arrival at its selected destination, the robot prompts the recipient for a security code or physical key and awaits acknowledgement of payload removal. In the future, the integration of HelpMate with robot manipulators, test equipment, and central institutional information systems will open new applications in more localized areas and should help overcome difficulties in filling transport staff positions.

  8. Maritime Intelligent Transport Systems

    NASA Astrophysics Data System (ADS)

    Pietrzykowski, Zbigniew

    The concept of intelligent transport systems, developed since 1980s, includes all modes of transport. Relevant developments in road transport are the most advanced. Recently water transport, particularly maritime transport, has gained more attention in this respect, in connection with building and further developments of maritime intelligent transport systems. The present state and directions of development of telematic systems in maritime transport will be discussed, with a focus on marine navigation.

  9. Transporting particulate material

    DOEpatents

    Aldred, Derek Leslie [North Hollywood, CA; Rader, Jeffrey A [North Hollywood, CA; Saunders, Timothy W [North Hollywood, CA

    2011-08-30

    A material transporting system comprises a material transporting apparatus (100) including a material transporting apparatus hopper structure (200, 202), which comprises at least one rotary transporting apparatus; a stationary hub structure (900) constraining and assisting the at least one rotary transporting apparatus; an outlet duct configuration (700) configured to permit material to exit therefrom and comprising at least one diverging portion (702, 702'); an outlet abutment configuration (800) configured to direct material to the outlet duct configuration; an outlet valve assembly from the material transporting system venting the material transporting system; and a moving wall configuration in the material transporting apparatus capable of assisting the material transporting apparatus in transporting material in the material transporting system. Material can be moved from the material transporting apparatus hopper structure to the outlet duct configuration through the at least one rotary transporting apparatus, the outlet abutment configuration, and the outlet valve assembly.

  10. Transporting Handicapped Students.

    ERIC Educational Resources Information Center

    Turner, Dayton Ray

    The book presents guidelines for adaptive transportation measures for handicapped students. Part 1 considers the transportation cycle as a means to evaluate individual student competencies at all logical points during the transportation experience. The transportation cycle is reviewed from deciding to transport the student to gaining access to…

  11. Review of adaptive optics OCT (AO-OCT): principles and applications for retinal imaging [Invited

    PubMed Central

    Pircher, Michael; Zawadzki, Robert J

    2017-01-01

    In vivo imaging of the human retina with a resolution that allows visualization of cellular structures has proven to be essential to broaden our knowledge about the physiology of this precious and very complex neural tissue that enables the first steps in vision. Many pathologic changes originate from functional and structural alterations on a cellular scale, long before any degradation in vision can be noted. Therefore, it is important to investigate these tissues with a sufficient level of detail in order to better understand associated disease development or the effects of therapeutic intervention. Optical retinal imaging modalities rely on the optical elements of the eye itself (mainly the cornea and lens) to produce retinal images and are therefore affected by the specific arrangement of these elements and possible imperfections in curvature. Thus, aberrations are introduced to the imaging light and image quality is degraded. To compensate for these aberrations, adaptive optics (AO), a technology initially developed in astronomy, has been utilized. However, the axial sectioning provided by retinal AO-based fundus cameras and scanning laser ophthalmoscope instruments is limited to tens of micrometers because of the rather small available numerical aperture of the eye. To overcome this limitation and thus achieve much higher axial sectioning in the order of 2-5µm, AO has been combined with optical coherence tomography (OCT) into AO-OCT. This enabled for the first time in vivo volumetric retinal imaging with high isotropic resolution. This article summarizes the technical aspects of AO-OCT and provides an overview on its various implementations and some of its clinical applications. In addition, latest developments in the field, such as computational AO-OCT and wavefront sensor less AO-OCT, are covered. PMID:28663890

  12. Review of adaptive optics OCT (AO-OCT): principles and applications for retinal imaging [Invited].

    PubMed

    Pircher, Michael; Zawadzki, Robert J

    2017-05-01

    In vivo imaging of the human retina with a resolution that allows visualization of cellular structures has proven to be essential to broaden our knowledge about the physiology of this precious and very complex neural tissue that enables the first steps in vision. Many pathologic changes originate from functional and structural alterations on a cellular scale, long before any degradation in vision can be noted. Therefore, it is important to investigate these tissues with a sufficient level of detail in order to better understand associated disease development or the effects of therapeutic intervention. Optical retinal imaging modalities rely on the optical elements of the eye itself (mainly the cornea and lens) to produce retinal images and are therefore affected by the specific arrangement of these elements and possible imperfections in curvature. Thus, aberrations are introduced to the imaging light and image quality is degraded. To compensate for these aberrations, adaptive optics (AO), a technology initially developed in astronomy, has been utilized. However, the axial sectioning provided by retinal AO-based fundus cameras and scanning laser ophthalmoscope instruments is limited to tens of micrometers because of the rather small available numerical aperture of the eye. To overcome this limitation and thus achieve much higher axial sectioning in the order of 2-5µm, AO has been combined with optical coherence tomography (OCT) into AO-OCT. This enabled for the first time in vivo volumetric retinal imaging with high isotropic resolution. This article summarizes the technical aspects of AO-OCT and provides an overview on its various implementations and some of its clinical applications. In addition, latest developments in the field, such as computational AO-OCT and wavefront sensor less AO-OCT, are covered.

  13. Requirements Modeling with the Aspect-oriented User Requirements Notation (AoURN): A Case Study

    NASA Astrophysics Data System (ADS)

    Mussbacher, Gunter; Amyot, Daniel; Araújo, João; Moreira, Ana

    The User Requirements Notation (URN) is a recent ITU-T standard that supports requirements engineering activities. The Aspect-oriented URN (AoURN) adds aspect-oriented concepts to URN, creating a unified framework that allows for scenario-based, goal-oriented, and aspect-oriented modeling. AoURN is applied to the car crash crisis management system (CCCMS), modeling its functional and non-functional requirements (NFRs). AoURN generally models all use cases, NFRs, and stakeholders as individual concerns and provides general guidelines for concern identification. AoURN handles interactions between concerns, capturing their dependencies and conflicts as well as the resolutions. We present a qualitative comparison of aspect-oriented techniques for scenario-based and goal-oriented requirements engineering. An evaluation carried out based on the metrics adapted from literature and a task-based evaluation suggest that AoURN models are more scalable than URN models and exhibit better modularity, reusability, and maintainability.

  14. Snow-(N)AO relationship revisited over the whole twentieth century

    NASA Astrophysics Data System (ADS)

    Douville, H.; Peings, Y.; Saint-Martin, D.

    2017-01-01

    Several studies suggest that the Siberian snow cover in fall is a source of predictability of the Arctic Oscillation (AO) in winter. Although a plausible dynamical mechanism was proposed, the robustness of this relationship was recently challenged. Here we use two atmospheric reanalyses to revisit the snow-AO relationship and its modulation across the whole twentieth century. While our results support a stratospheric pathway mechanism, they show that the snow-AO relationship has only emerged in the 1970s and should be rather analyzed as a contrasted multidecadal behavior of the North Atlantic Oscillation (NAO) and Pacific North America pattern. They confirm that the quasi-biennial oscillation is a plausible candidate for the modulation of the snow-(N)AO relationship across the twentieth century, but they further show that this modulation might be a purely stochastic effect. Therefore, they emphasize the limitations of any empirical prediction of the (N)AO only based on snow and/or sea ice predictors.

  15. Smart Growth and Transportation

    EPA Pesticide Factsheets

    Describes the relationship between smart growth and transportation, focusing smart and sustainable street design, transit-oriented development, parking management, sustainable transportation planning, and related resources.

  16. Up-Regulated Expression of AOS-LOXa and Increased Eicosanoid Synthesis in Response to Coral Wounding

    PubMed Central

    Lõhelaid, Helike; Teder, Tarvi; Tõldsepp, Kadri; Ekins, Merrick; Samel, Nigulas

    2014-01-01

    In octocorals, a catalase–like allene oxide synthase (AOS) and an 8R-lipoxygenase (LOX) gene are fused together encoding for a single AOS-LOX fusion protein. Although the AOS-LOX pathway is central to the arachidonate metabolism in corals, its biological function in coral homeostasis is unclear. Using an acute incision wound model in the soft coral Capnella imbricata, we here test whether LOX pathway, similar to its role in plants, can contribute to the coral damage response and regeneration. Analysis of metabolites formed from exogenous arachidonate before and after fixed time intervals following wounding indicated a significant increase in AOS-LOX activity in response to mechanical injury. Two AOS-LOX isoforms, AOS-LOXa and AOS-LOXb, were cloned and expressed in bacterial expression system as active fusion proteins. Transcription levels of corresponding genes were measured in normal and stressed coral by qPCR. After wounding, AOS-LOXa was markedly up-regulated in both, the tissue adjacent to the incision and distal parts of a coral colony (with the maximum reached at 1 h and 6 h post wounding, respectively), while AOS-LOXb was stable. According to mRNA expression analysis, combined with detection of eicosanoid product formation for the first time, the AOS-LOX was identified as an early stress response gene which is induced by mechanical injury in coral. PMID:24551239

  17. Optical-X-ray Observations of BL Lacertae Object AO 0235+164

    NASA Astrophysics Data System (ADS)

    Howard, Emily S.; Webb, James R.; Balonek, Thomas J.; McGrath, Elizabeth; Shrader, Chris R.

    1998-11-01

    The BL Lacertea object AO 0235+164 dramatically increased in brightness on October 20, 1997. This outburst was observed with the 1 meter SARA (Southeastern Association for Research in Astronomy) telescope located at Kitt Peak National Observatory (KPNO) located southwest of Tucson, Arizona. As a result of our observations, AO 0235+164 was also observed during the outbust by the Rossi X-ray Timing Experiment (RXTE) and Foggy Bottom Observaotry, Colgate Univserity, New York as a part of a Target of Opportunity (TOO) program. We present here the historical lightcurve of AO 0235+164, Optical observations during the ourtburst from the SARA and Foggy Bottom Observatories and X-ray observations from RXTE. Also, we present multifrequency data during this period and compare the variability of the Optical and X-ray bands.

  18. SAXO, the SPHERE extreme AO system: on-sky final performance and future improvements

    NASA Astrophysics Data System (ADS)

    Fusco, T.; Sauvage, J.-F.; Mouillet, D.; Costille, A.; Petit, C.; Beuzit, J.-L.; Dohlen, K.; Milli, J.; Girard, J.; Kasper, M.; Vigan, A.; Suarez, M.; Soenke, C.; Downing, M.; N'Diaye, M.; Baudoz, P.; Sevin, A.; Baruffolo, A.; Schmid, H.-M.; Salasnich, B.; Hugot, E.; Hubin, N.

    2016-07-01

    The SPHERE (Spectro-Polarimetric High-contrast Exoplanet Research) instrument aims at detecting extremely faint sources (giant extrasolar planets) in the vicinity of bright stars1. Such a challenging goal requires the use of a very-high-order performance Adaptive Optics [AO] system feeding the scientific instruments with a quasi-perfect flat wave front corrected from all the atmospheric turbulence and internal defects. This AO system, called SAXO (Sphere Ao for eXoplanet Observation) is the heart of the instrument, a heart beating 1200 time per second and providing unprecedented image quality for a large ground based telescope at optical/near infrared wavelength. We will present the latest results obtained on-sky, demonstrating its exceptional performance (in terms of correction quality, stability and robustness) and tremendous potentiality for high contrast imaging and more specifically for exoplanet discovery.

  19. Deep-water sponges (Porifera) from Bonaire and Klein Curaçao, Southern Caribbean.

    PubMed

    Van Soest, Rob W M; Meesters, Erik H W G; Becking, Leontine E

    2014-10-29

    Four submersible dives off the coast of Bonaire (Caribbean Netherlands) and Klein Curaçao (Curaçao) to depths of 99.5-242 m, covering lower mesophotic and upper dysphotic zones, yielded 52 sponge specimens belonging to 31 species. Among these we identified 13 species as new to science. These are Plakinastrella stinapa n. sp., Pachastrella pacoi n. sp., Characella pachastrelloides n. sp., Geodia curacaoensis n. sp., Caminus carmabi n. sp., Discodermia adhaerens n. sp., Clathria (Microciona) acarnoides n. sp., Antho (Acarnia) pellita n. sp., Parahigginsia strongylifera n. sp., Calyx magnoculata n. sp., Neopetrosia dutchi n. sp., Neopetrosia ovata n. sp. and Neopetrosia eurystomata n. sp. We also report an euretid hexactinellid, which belongs to the rare genus Verrucocoeloidea, recently described (2014) as V. liberatorii Reiswig & Dohrmann. The remaining 18 already known species are all illustrated by photos of the habit, either in situ or 'on deck', but only briefly characterized in an annotated table to confirm their occurrence in the Southern Caribbean. The habitat investigated-steep limestone rocks, likely representing Pleistocene fossil reefs--is similar to deep-water fossil reefs at Barbados of which the sponges were sampled and studied by Van Soest and Stentoft (1988). A comparison is made between the two localities, showing a high degree of similarity in sponge composition: 53% of the present Bonaire-Klein Curaçao species were also retrieved at Barbados. At the level of higher taxa (genera, families) Bonaire-Klein Curaçao shared approximately 80% of its lower mesophotic and upper dysphotic sponge fauna with Barbados, despite a distance between them of 1000 km, indicating high faunal homogeneity. We also preliminarily compared the shallow-water (euphotic) sponge fauna of Curaçao with the combined data available for the Barbados, Bonaire and Klein Curaçao mesophotic and upper dysphotic sponges, which resulted in the conclusion that the two faunas show only

  20. Novel algorithm implementations in DARC: the Durham AO real-time controller

    NASA Astrophysics Data System (ADS)

    Basden, Alastair; Bitenc, Urban; Jenkins, David

    2016-07-01

    The Durham AO Real-time Controller has been used on-sky with the CANARY AO demonstrator instrument since 2010, and is also used to provide control for several AO test-benches, including DRAGON. Over this period, many new real-time algorithms have been developed, implemented and demonstrated, leading to performance improvements for CANARY. Additionally, the computational performance of this real-time system has continued to improve. Here, we provide details about recent updates and changes made to DARC, and the relevance of these updates, including new algorithms, to forthcoming AO systems. We present the computational performance of DARC when used on different hardware platforms, including hardware accelerators, and determine the relevance and potential for ELT scale systems. Recent updates to DARC have included algorithms to handle elongated laser guide star images, including correlation wavefront sensing, with options to automatically update references during AO loop operation. Additionally, sub-aperture masking options have been developed to increase signal to noise ratio when operating with non-symmetrical wavefront sensor images. The development of end-user tools has progressed with new options for configuration and control of the system. New wavefront sensor camera models and DM models have been integrated with the system, increasing the number of possible hardware configurations available, and a fully open-source AO system is now a reality, including drivers necessary for commercial cameras and DMs. The computational performance of DARC makes it suitable for ELT scale systems when implemented on suitable hardware. We present tests made on different hardware platforms, along with the strategies taken to optimise DARC for these systems.

  1. Rise of the Machines: Automated Laser Guide Star Adaptive Optics Observations of Thousands of Objects with Robo-AO

    NASA Astrophysics Data System (ADS)

    Riddle, Reed L.; Baranec, C.; Law, N. M.; Tendulkar, S. P.; Ramaprakash, A. N.; Kulkarni, S. R.; Dekany, R.; Bui, K.; Burse, M.; Das, H.; Punnadi, S.; Chordia, P.

    2013-01-01

    Robo-AO is the first fully automated laser guide star adaptive optics instrument. Robo-AO has completed thousands of automated AO observations at the visible diffraction limit for several scientific programs during its first semester of science observations. These programs include: the Ultimate Binarity Survey to examine stellar binarity properties across the main sequence and beyond; a survey of 1,000 Kepler objects of interest; the multiplicity of solar type stars; and several programs for high precision astrometric observations. A new infrared camera is under development for Robo-AO, and a clone of the system is in the planning stages. This presentation will discuss the Robo-AO instrument capabilities, summarize the science programs undertaken, and discuss the future of Robo-AO.

  2. The Robo-AO software: fully autonomous operation of a laser guide star adaptive optics and science system

    NASA Astrophysics Data System (ADS)

    Riddle, Reed L.; Burse, Mahesh P.; Law, Nicholas M.; Tendulkar, Shriharsh P.; Baranec, Christoph; Rudy, Alexander R.; Sitt, Marland; Arya, Ankit; Papadopoulos, Athanasios; Ramaprakash, A. N.; Dekany, Richard G.

    2012-07-01

    Robo-AO is the first astronomical laser guide star adaptive optics (AO) system designed to operate completely independent of human supervision. A single computer commands the AO system, the laser guide star, visible and near-infrared science cameras (which double as tip-tip sensors), the telescope, and other instrument functions. Autonomous startup and shutdown sequences as well as concatenated visible observations were demonstrated in late 2011. The fully robotic software is currently operating during a month long demonstration of Robo- AO at the Palomar Observatory 60-inch telescope.

  3. Thyroid hormone transport by monocarboxylate transporters.

    PubMed

    Visser, W Edward; Friesema, Edith C H; Jansen, Jurgen; Visser, Theo J

    2007-06-01

    Thyroid hormone (TH) is essential for the normal development and metabolism of different tissues. TH action and metabolism take place intracellularly, which requires cellular uptake via transporters. Several transporter families have been identified, of which the monocarboxylate transporter (MCT) family deserves special attention. So far, only MCT1, MCT2, MCT3, MCT4 and MCT6 have been demonstrated to transport monocarboxylates; MCT8 has been identified as a specific TH transporter. MCT8 mutations in humans are associated with severe psychomotor retardation and elevated 3,3',5-triiodothyronine (T(3)) levels. Recently, MCT8 knockout mice have been shown to perfectly imitate the thyroid state in patients with MCT8 mutations; however, they lack the neurological defects. Although it was long hypothesized that a T-type amino acid transporter also transports iodothyronines, it only recently became clear that MCT10 is involved in the bidirectional transport of aromatic amino acids and iodothyronines. MCT10 preferentially transports T(3) even more effectively than does MCT8. However, its precise function in the human body is poorly understood.

  4. GPS-Based Navigation And Orbit Determination for the AMSAT AO-40 Satellite

    NASA Technical Reports Server (NTRS)

    Davis, George; Moreau, Michael; Carpenter, Russell; Bauer, Frank

    2002-01-01

    The AMSAT OSCAR-40 (AO-40) spacecraft occupies a highly elliptical orbit (HEO) to support amateur radio experiments. An interesting aspect of the mission is the attempted use of GPS for navigation and attitude determination in HEO. Previous experiences with GPS tracking in such orbits have demonstrated the ability to acquire GPS signals, but very little data were produced for navigation and orbit determination studies. The AO-40 spacecraft, flying two Trimble Advanced Navigation Sensor (TANS) Vector GPS receivers for signal reception at apogee and at perigee, is the first to demonstrate autonomous tracking of GPS signals from within a HEO with no interaction from ground controllers. Moreover, over 11 weeks of total operations as of June 2002, the receiver has returned a continuous stream of code phase, Doppler, and carrier phase measurements useful for studying GPS signal characteristics and performing post-processed orbit determination studies in HEO. This paper presents the initial efforts to generate AO-40 navigation solutions from pseudorange data reconstructed from the TANS Vector code phase, as well as to generate a precise orbit solution for the AO-40 spacecraft using a batch filter.

  5. Is the BL Lacertae object AO 0235 + 164 being lensed by its intervening MG II absorber?

    NASA Astrophysics Data System (ADS)

    Abraham, Roberto G.; Crawford, Carolin S.; Merrifield, Michael R.; Hutchings, John B.; McHardy, Ian M.

    1993-09-01

    We report the results of deep CFHT imaging of the BL Lac object AO 0235 + 164. This object exhibits Mg II absorption features and has been considered to be the best candidate for a microlensed BL Lac on the basis of its multiple redshift systems, decentered host, and extreme apparent superluminal motion. We test the microlensing hypothesis by modeling our images with a two-dimensional image fitting routine. The resulting best-fit models allow us to put strong constraints on lensing scenarios for this object, and to put limits on the mass-to-light ratio of the foreground Mg II absorbing galaxy. We conclude that, while AO 0235 + 164 is almost certainly being weakly amplified by macrolensing, microlensing by stars in the foreground lens is unnecessary in order to explain the observed properties of AO 0235 + 164. These results are combined with the work of previous authors to suggest that the (probably lensing) Mg II absorbing galaxy in the foreground of AO 0235 + 164 is embedded in a cooling flow.

  6. Performance of a MEMS-based AO-OCT system using Fourier Reconstruction

    SciTech Connect

    Evans, J; Zawadzki, R; Jones, S; Olivier, S; Werner, J S

    2009-01-21

    Adaptive optics (AO) and optical coherence tomography (OCT) are powerful imaging modalities that, when combined, can provide high-resolution (3.5 {micro}m isotropic), 3-D images of the retina. The AO-OCT system at UC Davis has demonstrated the utility of this technology for microscopic, volumetric, in vivo retinal imaging. The current system uses an AOptix bimorph deformable mirror (DM) for low-order, high-stroke correction and a 140-actuator Boston Micromachines DM for high-order correction. Developments to improve performance or functionality of the instrument are on-going. Based on previous work in system characterization we have focused on improved AO control. We present preliminary results and remaining challenges for a newly implemented Fourier transform reconstructor (FTR). The previously reported error budget analysis is also reviewed and updated, with consideration of how to improve both the amount of residual error and the robustness of the system. Careful characterization of the AO system will lead to improved performance and inform the design of future systems.

  7. Extreme AO: The future of high-contrast imaging with adaptive optics

    NASA Astrophysics Data System (ADS)

    Macintosh, B.

    2001-05-01

    Title: Extreme AO: The future of high-contrast-imaging with adaptive optics. Adaptive optics (AO) partially cancels wavefront aberrations caused by atmospheric turbulence and can allow ground-basd telescope to reach their full diffraction-limited resolution. A fundamental limitation of all AO systems is that they have little effect on the atmospheric scattered light halo beyond a control radius roughly given by the wavelength of interest divided by the effective actuator spaceing d; for typical modern AO systems, d=60 cm and the control radius is about 0.6 arcseconds at H band. AO can still enhance contrast even beyond this radius, especially for point-source companions, by concentrating the light from the companion into a diffraction-limited spike, but the residual light remains a limitation on our ability to carry out high-contrast imaging from the ground. We will discuss potential improvements to AO over the next decade and the science they will enable. First, in the near term, high-order AO systems will soon be operational on most 8-10 m telescopes; such systems are theoretically capable of directly detecting extrasolar planets in wide (20-150 AU) orbits, and the capabilities and limitations of these systems will be discussed. Second, in the moderate term, new instrument technologies could substantially increase the performance of these systems, including exotic phase-based coronagraphs or "dark speckle" techniques. Third, it will soon be possible to construct "extreme" adaptive optics (EAO) systems, with many thousand actuators and d=5-20cm, capable of more deeply surpressing the atmospheric halo out to a much larger radius than current systems. Coronagraphs and EAO will substantially increase our sensitivity to diffuse circumstellar dust and could conceivably reach the contrast levels necessary to see giant plants around a handful of nearby stars. Finally, within a decade construction should be underway on next-generation extremely large (25-100 m) telescopes

  8. Improved tilt sensing in an LGS-based tomographic AO system based on instantaneous PSF estimation

    NASA Astrophysics Data System (ADS)

    Veran, Jean-Pierre

    2013-12-01

    Laser guide star (LGS)-based tomographic AO systems, such as Multi-Conjugate AO (MCAO), Multi-Object AO (MOAO) and Laser Tomography AO (LTAO), require natural guide stars (NGSs) to sense tip-tilt (TT) and possibly other low order modes, to get rid of the LGS-tilt indetermination problem. For example, NFIRAOS, the first-light facility MCAO system for the Thirty Meter Telescope requires three NGSs, in addition to six LGSs: two to measure TT and one to measure TT and defocus. In order to improve sky coverage, these NGSs are selected in a so-called technical field (2 arcmin in diameter for NFIRAOS), which is much larger than the on-axis science field (17x17 arcsec for NFIRAOS), on which the AO correction is optimized. Most times, the NGSs are far off-axis and thus poorly corrected by the high-order AO loop, resulting in spots with low contrast and high speckle noise. Accurately finding the position of such spots is difficult, even with advanced methods such as matched-filtering or correlation, because these methods rely on the knowledge of an average spot image, which is quite different from the instantaneous spot image, especially in case of poor correction. This results in poor tilt estimation, which, ultimately, impacts sky coverage. We propose to improve the estimation of the position of the NGS spots by using, for each frame, a current estimate of the instantaneous spot profile instead of an average profile. This estimate can be readily obtained by tracing wavefront errors in the direction of the NGS through the turbulence volume. The latter is already computed by the tomographic process from the LGS measurements as part of the high order AO loop. Computing such a wavefront estimate has actually already been proposed for the purpose of driving a deformable mirror (DM) in each NGS WFS, to optically correct the NGS spot, which does lead to improved centroiding accuracy. Our approach, however, is much simpler, because it does not require the complication of extra DMs

  9. Water-transporting proteins.

    PubMed

    Zeuthen, Thomas

    2010-04-01

    Transport through lipids and aquaporins is osmotic and entirely driven by the difference in osmotic pressure. Water transport in cotransporters and uniporters is different: Water can be cotransported, energized by coupling to the substrate flux by a mechanism closely associated with protein. In the K(+)/Cl(-) and the Na(+)/K(+)/2Cl(-) cotransporters, water is entirely cotransported, while water transport in glucose uniporters and Na(+)-coupled transporters of nutrients and neurotransmitters takes place by both osmosis and cotransport. The molecular mechanism behind cotransport of water is not clear. It is associated with the substrate movements in aqueous pathways within the protein; a conventional unstirred layer mechanism can be ruled out, due to high rates of diffusion in the cytoplasm. The physiological roles of the various modes of water transport are reviewed in relation to epithelial transport. Epithelial water transport is energized by the movements of ions, but how the coupling takes place is uncertain. All epithelia can transport water uphill against an osmotic gradient, which is hard to explain by simple osmosis. Furthermore, genetic removal of aquaporins has not given support to osmosis as the exclusive mode of transport. Water cotransport can explain the coupling between ion and water transport, a major fraction of transepithelial water transport and uphill water transport. Aquaporins enhance water transport by utilizing osmotic gradients and cause the osmolarity of the transportate to approach isotonicity.

  10. The stimulating role of subunit F in ATPase activity inside the A1-complex of the Methanosarcina mazei Gö1 A1AO ATP synthase.

    PubMed

    Singh, Dhirendra; Sielaff, Hendrik; Sundararaman, Lavanya; Bhushan, Shashi; Grüber, Gerhard

    2016-02-01

    A1AO ATP synthases couple ion-transport of the AO sector and ATP synthesis/hydrolysis of the A3B3-headpiece via their stalk subunits D and F. Here, we produced and purified stable A3B3D- and A3B3DF-complexes of the Methanosarcina mazei Gö1 A-ATP synthase as confirmed by electron microscopy. Enzymatic studies with these complexes showed that the M. mazei Gö1 A-ATP synthase subunit F is an ATPase activating subunit. The maximum ATP hydrolysis rates (Vmax) of A3B3D and A3B3DF were determined by substrate-dependent ATP hydrolysis experiments resulting in a Vmax of 7.9 s(-1) and 30.4 s(-1), respectively, while the KM is the same for both. Deletions of the N- or C-termini of subunit F abolished the effect of ATP hydrolysis activation. We generated subunit F mutant proteins with single amino acid substitutions and demonstrated that the subunit F residues S84 and R88 are important in stimulating ATP hydrolysis. Hybrid formation of the A3B3D-complex with subunit F of the related eukaryotic V-ATPase of Saccharomyces cerevisiae or subunit ε of the F-ATP synthase from Mycobacterium tuberculosis showed that subunit F of the archaea and eukaryotic enzymes are important in ATP hydrolysis.

  11. Transportation Technology: Rail Transport and Logistics

    ERIC Educational Resources Information Center

    Lang, Aaron B.

    2011-01-01

    Transportation can simply be defined as the movement of goods, services, and people from one location to another. Without an efficient means to transport goods from place to place, the economy would be nothing like it is today. Throughout the history of the United States, American railroads have paved the way toward creating a nation of great…

  12. Transportation Technology: Rail Transport and Logistics

    ERIC Educational Resources Information Center

    Lang, Aaron B.

    2011-01-01

    Transportation can simply be defined as the movement of goods, services, and people from one location to another. Without an efficient means to transport goods from place to place, the economy would be nothing like it is today. Throughout the history of the United States, American railroads have paved the way toward creating a nation of great…

  13. Secure Transportation Management

    SciTech Connect

    Gibbs, P. W.

    2014-10-15

    Secure Transport Management Course (STMC) course provides managers with information related to procedures and equipment used to successfully transport special nuclear material. This workshop outlines these procedures and reinforces the information presented with the aid of numerous practical examples. The course focuses on understanding the regulatory framework for secure transportation of special nuclear materials, identifying the insider and outsider threat(s) to secure transportation, organization of a secure transportation unit, management and supervision of secure transportation units, equipment and facilities required, training and qualification needed.

  14. The Effectiveness of a Mixed-Mode Survey on Domestic Violence in Curaçao: Response and Data Quality

    ERIC Educational Resources Information Center

    van Wijk, Nikil; de Leeuw, Edith; de Bruijn, Jeanne

    2015-01-01

    To collect reliable statistical data on domestic violence in Curaçao, we conducted a large-scale quantitative study (n = 816). To meet with the special needs of the population and topic, we designed a tailored mixed-mode survey to assess the prevalence of domestic violence in Curaçao and its health consequences. Great care was taken to reduce…

  15. ecoAO: A Simple System for the Study of Human Aldehyde Oxidases Role in Drug Metabolism

    PubMed Central

    2017-01-01

    Although aldehyde oxidase (AO) is an important hepatic drug-metabolizing enzyme, it remains understudied and is consequently often overlooked in preclinical studies, an oversight that has resulted in the failure of multiple clinical trials. AO’s preclusion to investigation stems from the following: (1) difficulties synthesizing metabolic standards due to the chemospecificity and regiospecificity of the enzyme and (2) significant inherent variability across existing in vitro systems including liver cytosol, S9 fractions, and primary hepatocytes, which lack specificity and generate discordant expression and activity profiles. Here, we describe a practical bacterial biotransformation system, ecoAO, addressing both issues simultaneously. ecoAO is a cell paste of MoCo-producing Escherichia coli strain TP1017 expressing human AO. It exhibits specific activity toward known substrates, zoniporide, 4-trans-(N,N-dimethylamino)cinnamaldehyde, O6-benzylguanine, and zaleplon; it also has utility as a biocatalyst, yielding milligram quantities of synthetically challenging metabolite standards such as 2-oxo-zoniporide. Moreover, ecoAO enables routine determination of kcat and V/K, which are essential parameters for accurate in vivo clearance predictions. Furthermore, ecoAO has potential as a preclinical in vitro screening tool for AO activity, as demonstrated by its metabolism of 3-aminoquinoline, a previously uncharacterized substrate. ecoAO promises to provide easy access to metabolites with the potential to improve pharmacokinetic clearance predictions and guide drug development. PMID:28884164

  16. Basic Transportation Economics

    NASA Technical Reports Server (NTRS)

    Kneafsey, J. T.

    1972-01-01

    Transportation economics is an integral part of all transportation activities. Refined, detailed, and careful economic analyses consider conduct-performance methodology and the specifications of production, cost and demand functions.

  17. Transportation and handling loads

    NASA Technical Reports Server (NTRS)

    Ostrem, F. E.

    1971-01-01

    Criteria and recommended practices are presented for the prediction and verification of transportation and handling loads for the space vehicle structure and for monitoring these loads during transportation and handling of the vehicle or major vehicle segments. Elements of the transportation and handling systems, and the forcing functions and associated loads are described. The forcing functions for common carriers and typical handling devices are assessed, and emphasis is given to the assessment of loads at the points where the space vehicle is supported during transportation and handling. Factors which must be considered when predicting the loads include the transportation and handling medium; type of handling fixture; transport vehicle speed; types of terrain; weather (changes in pressure of temperature, wind, etc.); and dynamics of the transportation modes or handling devices (acceleration, deceleration, and rotations of the transporter or handling device).

  18. Transportation Management Workshop: Proceedings

    SciTech Connect

    Not Available

    1993-10-01

    This report is a compilation of discussions presented at the Transportation Management Workshop held in Gaithersburg, Maryland. Topics include waste packaging, personnel training, robotics, transportation routing, certification, containers, and waste classification.

  19. Phosphorus: Riverine system transport

    USDA-ARS?s Scientific Manuscript database

    The transport and transformation of phosphorus (P) in riverine systems fundamentally affects the outcome of watershed mitigation strategies aimed at curbing downstream eutrophication. Phosphorus transport and transformations in streams and rivers are mediated by physical (sediment deposition and res...

  20. Thermodynamics of nuclear transport

    NASA Astrophysics Data System (ADS)

    Wang, Ching-Hao; Mehta, Pankaj; Elbaum, Michael

    Molecular transport across the nuclear envelope is important for eukaryotes for gene expression and signaling. Experimental studies have revealed that nuclear transport is inherently a nonequilibrium process and actively consumes energy. In this work we present a thermodynamics theory of nuclear transport for a major class of nuclear transporters that are mediated by the small GTPase Ran. We identify the molecular elements responsible for powering nuclear transport, which we term the ``Ran battery'' and find that the efficiency of transport, measured by the cargo nuclear localization ratio, is limited by competition between cargo molecules and RanGTP to bind transport receptors, as well as the amount of NTF2 (i.e. RanGDP carrier) available to circulate the energy flow. This picture complements our current understanding of nuclear transport by providing a comprehensive thermodynamics framework to decipher the underlying biochemical machinery. Pm and CHW were supported by a Simons Investigator in the Mathematical Modeling in Living Systems grant (to PM).

  1. Termination of Pregnancy in Curaçao: Need for Improvement of Sexual and Reproductive Healthcare

    PubMed Central

    Boersma, Adriana A.; Alberts, Jantina F.; de Bruijn, Jeanne; Jong, Betty Meyboom-de; Kleiverda, Gunilla

    2012-01-01

    Background: In Curaçao Termination of Pregnancy (TOP) is still forbidden by law, although a policy of tolerance has been stipulated since 1999. This paper is about the prevalence of TOP and about its health complications. These data on TOP are officially unknown but are suspected to be rather high. Methods: One year registration of illegal performed termination of pregnancy cases by all general physicians (GPs) practicing TOP in Curaçao. The registration included patient characteristics according to the model of the National Abortion Registration in The Netherlands, adjusted to the local Curaçao situation. Socio demographic characteristics, number of previous pregnancies and TOPs, pregnancy duration, contraception methods and reason for failure were registered. The comparative part of the research compares TOP rates of Curaçao with those of Antillean women in the Netherlands. The gynaecologists in the referral hospital registered complications requiring hospital admission after TOP. Results: All GPs performing TOP participated and the majority registered extensively. The total number of registered TOP was 1126. 666 of the 1126 were registered using the local adjusted Abortion Registration Model. With 30.000 women aged between 15 and 45 living in Curaçao, the TOP rate was at least 38 (per 1000 in that age category), comparable to rates for Antillean women in the Netherlands. Mean age was 26.9 years. Nearly half (47%) had one or more TOPs before; the majority (53%) was less than 7 weeks pregnant and two third (67%) had one or more children. Two third of the women did not use contraception (63%). For those using contraception, main reason for failure was inconsistent use (50%). There were 14 hospital admissions due to complications of TOP. Conclusion: The number of TOP is high in Curaçao and comparable to (first generation) Antillean women living abroad in the Netherlands. Most unintended pregnancies originated from no or inconsistent use of reliable

  2. Cabrillo College Transportation Study.

    ERIC Educational Resources Information Center

    Willett, Terrence

    This report provides results of the survey and other sources of information which have been used to develop a transportation management plan at Cabrillo College (California). In 2000, Cabrillo College organized a Transportation Management Committee to review the existing transportation situation and develop and implement a plan with the goal of…

  3. Transportation in African Development.

    ERIC Educational Resources Information Center

    Altschul, Robert D.

    1980-01-01

    Examines the structure, role, and needs of Africa's national and intracontinental transportation system. Characteristics of rail, water, road, and air transportation are examined. The conclusion is that high investment in transportation systems is essential to the development process. (Author/KC)

  4. How stressful is transportation?

    USDA-ARS?s Scientific Manuscript database

    It is common for cattle to be transported multiple times during their production life cycle. Transportation events may include calves shipped to backgrounding facilities and feed yards, as well as pregnant cows that may be transported to sale barns or relocated due to drought to access a pasture or ...

  5. Using Telematics in Transport

    NASA Astrophysics Data System (ADS)

    Mikulski, Jerzy

    Design and development of telematics transport systems represents a new approach to solving transportation problems. Telematics offers large opportunities to strengthen the positive features of transport (availability, mobility), while minimizing its negative impacts (e.g. environmental pollution, energy consumption, congestion, accidents, infrastructure construction costs) without any additional spending on investment.

  6. Directory of Transportation Education.

    ERIC Educational Resources Information Center

    Department of Transportation, Washington, DC.

    This directory lists institutions of higher education that offer degree and non-degree programs in various transportation fields and modes, including aviation, highway, urban mass transportation, railroad, water transport, pipeline, intermodal, and environmental and consumer education. The book catalogs courses and degrees offered, names of…

  7. Packaging, transportation of LLW

    SciTech Connect

    Shelton, P.

    1994-12-31

    This presentation is an overview of the regulations and requirements for the packaging and transportation of low-level radioactive wastes. United States Environmental Protection Agency and Department of Transportation regulations governing the classification of wastes and the transport documentation are also described.

  8. Transport and transporters in the endoplasmic reticulum.

    PubMed

    Csala, Miklós; Marcolongo, Paola; Lizák, Beáta; Senesi, Silvia; Margittai, Eva; Fulceri, Rosella; Magyar, Judit E; Benedetti, Angelo; Bánhegyi, Gábor

    2007-06-01

    Enzyme activities localized in the luminal compartment of the endoplasmic reticulum are integrated into the cellular metabolism by transmembrane fluxes of their substrates, products and/or cofactors. Most compounds involved are bulky, polar or even charged; hence, they cannot be expected to diffuse through lipid bilayers. Accordingly, transport processes investigated so far have been found protein-mediated. The selective and often rate-limiting transport processes greatly influence the activity, kinetic features and substrate specificity of the corresponding luminal enzymes. Therefore, the phenomenological characterization of endoplasmic reticulum transport contributes largely to the understanding of the metabolic functions of this organelle. Attempts to identify the transporter proteins have only been successful in a few cases, but recent development in molecular biology promises a better progress in this field.

  9. The SCExAO high contrast imager: transitioning from commissioning to science

    NASA Astrophysics Data System (ADS)

    Jovanovic, N.; Guyon, O.; Lozi, J.; Currie, T.; Hagelberg, J.; Norris, B.; Singh, G.; Pathak, P.; Doughty, D.; Goebel, S.; Males, J.; Kuhn, J.; Serabyn, E.; Tuthill, P.; Schworer, G.; Martinache, F.; Kudo, T.; Kawahara, H.; Kotani, T.; Ireland, M.; Feger, T.; Rains, A.; Bento, J.; Schwab, C.; Coutts, D.; Cvetojevic, N.; Gross, S.; Arriola, A.; Lagadec, T.; Kasdin, J.; Groff, T.; Mazin, B.; Minowa, Y.; Takato, N.; Tamura, M.; Takami, H.; Hayashi, M.

    2016-07-01

    SCExAO is the premier high-contrast imaging platform for the Subaru Telescope. It offers high Strehl ratios at near-IR wavelengths (y-K band) with stable pointing and coronagraphs with extremely small inner working angles, optimized for imaging faint companions very close to the host. In the visible, it has several interferometric imagers which offer polarimetric and spectroscopic capabilities. A recent addition is the RHEA spectrograph enabling spatially resolved high resolution spectroscopy of the surfaces of giant stars, for example. New capabilities on the horizon include post-coronagraphic spectroscopy, spectral differential imaging, nulling interferometry as well as an integral field spectrograph and an MKID array. Here we present the new modules of SCExAO, give an overview of the current commissioning status of each of the modules and present preliminary results.

  10. Identification and calibration of the interaction matrix parameters for AO and MCAO systems

    NASA Astrophysics Data System (ADS)

    Neichel, Benoit; Parisot, Amelie; Petit, Cyril; Fusco, Thierry; Rigaut, François

    2012-07-01

    New tomographic Adaptive Optics (AO) concepts require a good knowledge of the system geometry and characteristics. These parameters are used to feed the tomographic reconstructors. In this paper we present a method to precisely identify the parameters required to construct an accurate synthetic set of models such as inuence functions, mis-registrations, directions of analysis or altitude of the DMs. The method is based on a multiparameter t of the interaction matrix. This identication method nds also its application in high contrast AO systems, such as SPHERE : in that case it is used as a diagnostic tool in order to precisely realign the system. The method has been tested and successfully implemented on HOMER, SPHERE and GeMS. Experimental results for these three systems are presented.

  11. The role of AO external fixation in proximal femoral osteotomies in the pediatric neuromuscular population.

    PubMed

    Handelsman, John E; Weinberg, Jacob; Razi, Afshin; Mulley, Debra A

    2004-09-01

    Internal fixation in proximal femoral osteotomies using traditional devices may be sub-optimal in children with neuromuscular disorders who have small or osteopenic bone. In this population, between 1988 and 2000, we performed 36 proximal femoral varus osteotomies in 28 patients. These were controlled by the AO external fixator. The average age at surgery was 7 years (range, 2-13 years). A mean varus correction of 34 degrees (range, 15-90 degrees) was obtained. Complications consisted of one superficial pin tract infection, one skin breakdown, and one non-union. Other than the non-union, all osteotomies were stable at the time of the fixator removal. The AO external fixator is an effective alternative in maintaining corrective proximal femoral osteotomies in children with fragile bones.

  12. DM dimensioning for the next generation AO systems : strategies and rules

    NASA Astrophysics Data System (ADS)

    Costille, A.; Conan, J.-M.

    2007-07-01

    Adaptive optics (AO) provides a real time correction of turbulence and allows to improve the angular resolution of the astronomical telescopes. The design of AO systems and of its key components (deformable mirror (DM), wave-front sensors...) is very important to provide the best performance. The definition rules are well known for 10m class telescopes. However the study of the next generation of telescopes, especially the Extremely Large Telescope (ELT), associated with the development of new technological solutions, particularly concerning DMs, require to refine and in some cases to reconsider these rules. Both turbulent parameters (seeing, outer scale ...), telescope effects, system design and performance requirements have to be considered in order to define the DM key parameters (stroke, inter-actuator stroke, influence function ...). We present a study based on the combination of analytical expressions and numerical simulation results. We do not give absolute rules of design but we present key aspects to keep in mind when designing the DM.

  13. Pharmacology of Iron Transport

    PubMed Central

    Byrne, Shaina L.; Krishnamurthy, Divya; Wessling-Resnick, Marianne

    2013-01-01

    Elucidating the molecular basis for the regulation of iron uptake, storage, and distribution is necessary to understand iron homeostasis. Pharmacological tools are emerging to identify and distinguish among different iron transport pathways. Stimulatory or inhibitory small molecules with effects on iron uptake can help characterize the mechanistic elements of iron transport and the roles of the transporters involved in these processes. In particular, iron chelators can serve as potential pharmacological tools to alleviate diseases of iron overload. This review focuses on the pharmacology of iron transport, introducing iron transport membrane proteins and known inhibitors. PMID:23020294

  14. Pharmacology of iron transport.

    PubMed

    Byrne, Shaina L; Krishnamurthy, Divya; Wessling-Resnick, Marianne

    2013-01-01

    Elucidating the molecular basis for the regulation of iron uptake, storage, and distribution is necessary to understand iron homeostasis. Pharmacological tools are emerging to identify and distinguish among different iron transport pathways. Stimulatory or inhibitory small molecules with effects on iron uptake can help characterize the mechanistic elements of iron transport and the roles of the transporters involved in these processes. In particular, iron chelators can serve as potential pharmacological tools to alleviate diseases of iron overload. This review focuses on the pharmacology of iron transport, introducing iron transport membrane proteins and known inhibitors.

  15. Transportation and public health.

    PubMed

    Litman, Todd

    2013-01-01

    This article investigates various ways that transportation policy and planning decisions affect public health and better ways to incorporate public health objectives into transport planning. Conventional planning tends to consider some public health impacts, such as crash risk and pollution emissions measured per vehicle-kilometer, but generally ignores health problems resulting from less active transport (reduced walking and cycling activity) and the additional crashes and pollution caused by increased vehicle mileage. As a result, transport agencies tend to undervalue strategies that increase transport system diversity and reduce vehicle travel. This article identifies various win-win strategies that can help improve public health and other planning objectives.

  16. Assessment of Assembling Objects (AO) for Improving Predictive Performance of the Armed Forces Qualification Test

    DTIC Science & Technology

    2011-04-01

    Although the ASVAB has not historically been predictive of attrition ( Laurence , Naughton, & Harris, 1996), the AO subtest has indeed shown...internal consistency (e.g., Earles & Ree , 1992). Alderton and colleagues (1997) found that PC had fairly low test-retest reliability, which was well... Ree (1992) found that WK is a slightly better predictor of course grades than PC across a variety of job types. Mirroring the research on the two

  17. Real-time control for the high order, wide field DRAGON AO test bench

    NASA Astrophysics Data System (ADS)

    Basden, Alastair; Bharmal, Nazim A.; Bitenc, Urban; Dipper, Nigel; Morris, Tim; Myers, Richard; Reeves, Andrew; Younger, Eddy

    2014-07-01

    DRAGON is a high order, wide field AO test-bench at Durham. A key feature of DRAGON is the ability to be operated at real-time rates, i.e. frame rates of up to 1kHz, with low latency to maintain AO performance. Here, we will present the real-time control architecture for DRAGON, which includes two deformable mirrors, eight wavefront sensors and thousands of Shack-Hartmann sub-apertures. A novel approach has been taken to allow access to the wavefront sensor pixel stream, reducing latency and peak computational load, and this technique can be implemented for other similar wavefront sensor cameras with no hardware costs. We report on experience with an ELT-suitable wavefront sensor camera. DRAGON will form the basis for investigations into hardware acceleration architectures for AO real-time control, and recent work on GPU and many-core systems (including the Xeon Phi) will be reported. Additionally, the modular structure of DRAGON, its remote control capabilities, distribution of AO telemetry data, and the software concepts and architecture will be reported. Techniques used in DRAGON for pixel processing, slope calculation and wavefront reconstruction will be presented. This will include methods to handle changes in CN2 profile and sodium layer profile, both of which can be modelled in DRAGON. DRAGON software simulation techniques linking hardware-in-the-loop computer models to the DRAGON real-time system and control software will also be discussed. This tool allows testing of the DRAGON system without requiring physical hardware and serves as a test-bed for ELT integration and verification techniques.

  18. Analysis of Alternatives (AoA) for KC-135 Recapitalization. Executive Summary

    DTIC Science & Technology

    2006-01-01

    Integrative research projects and work on modeling and simulation are conducted on a PAF-wide basis. The research reported here was prepared within the...Electric and Pratt & Whitney. The Air Force’s Aeronautical Systems Center, part of Air Force Materiel Command, proposed three new- design tankers that were...and Analysis Division (AMC/A59) made significant contributions to the AoA’s effectiveness analysis, especially in the detailed modeling of tanker

  19. Bridging FPGA and GPU technologies for AO real-time control

    NASA Astrophysics Data System (ADS)

    Perret, Denis; Lainé, Maxime; Bernard, Julien; Gratadour, Damien; Sevin, Arnaud

    2016-07-01

    Our team has developed a common environment for high performance simulations and real-time control of AO systems based on the use of Graphics Processors Units in the context of the COMPASS project. Such a solution, based on the ability of the real time core in the simulation to provide adequate computing performance, limits the cost of developing AO RTC systems and makes them more scalable. A code developed and validated in the context of the simulation may be injected directly into the system and tested on sky. Furthermore, the use of relatively low cost components also offers significant advantages for the system hardware platform. However, the use of GPUs in an AO loop comes with drawbacks: the traditional way of offloading computation from CPU to GPUs - involving multiple copies and unacceptable overhead in kernel launching - is not well suited in a real time context. This last application requires the implementation of a solution enabling direct memory access (DMA) to the GPU memory from a third party device, bypassing the operating system. This allows this device to communicate directly with the real-time core of the simulation feeding it with the WFS camera pixel stream. We show that DMA between a custom FPGA-based frame-grabber and a computation unit (GPU, FPGA, or Coprocessor such as Xeon-phi) across PCIe allows us to get latencies compatible with what will be needed on ELTs. As a fine-grained synchronization mechanism is not yet made available by GPU vendors, we propose the use of memory polling to avoid interrupts handling and involvement of a CPU. Network and Vision protocols are handled by the FPGA-based Network Interface Card (NIC). We present the results we obtained on a complete AO loop using camera and deformable mirror simulators.

  20. World-wide deployment of Robo-AO visible-light robotic laser adaptive optics systems

    NASA Astrophysics Data System (ADS)

    Baranec, Christoph; Riddle, Reed; Law, Nicholas Michael; Lu, Jessica R.; Tonry, John; Tully, R. Brent; Wright, Shelley; Kulkarni, Shrinivas; Severson, Scott; Choi, Philip; Ramaprakash, A.; Chun, Mark; Connelley, Mike; Tokunaga, Alan; Hall, Donald

    2015-08-01

    In the next few years, several modest-sized telescopes around the world will be upgraded with autonomous laser adaptive optics systems based on the Robo-AO prototype deployed at the Palomar Observatory 1.5-m telescope. The prototype commenced scientific operations in June 2012 and more than 19,000 observations have since been performed at the ~0.12" visible-light diffraction limit. We are planning to move the prototype system to the 2.1-m telescope at Kitt Peak for a 3-year deployment which will serve a consortium of users including Caltech, the University of Hawai`i, IUCAA, NCU and institutions in China. Additionally, 2 months per year will be made available to the US astronomical community.New Robo-AO systems are in various stages of development: a clone by IUCAA for the 2-m IGO telescope in India; a natural guide star variant, KAPAO, by Pomona College at the 1-m Table Mountain telescope in California; and second generation Robo-AO systems are planned for the 3-m IRTF and 2.2-m University of Hawai'i telescopes on Maunakea, Hawai`i. The latter will exploit Maunakea's excellent observing conditions to provide higher Strehl ratios, sharper imaging, ~0.07", and correction to lambda = 400 nm. An additional infrared integral-field spectrograph will be fed by the UH 2.2-m Robo-AO system to quickly classify transients, such as supernovae and asteroids, discovered by the ATLAS system in Hawai`i.

  1. The investigation of determination asteroids positions errors by observations of telescope SBG AO UFU

    NASA Astrophysics Data System (ADS)

    Kaizer, G. T.; Skripnichenko, P. V.

    2013-07-01

    The article is about investigation of influence astrometric CCD image processing conditions on the accuracy of determining the positions of asteroids. The main this research's problem is dependence of calculatedasteroids coordinates error from used in the processing mathematical model that approximated the image of the objects on the CCD image. In thearticle described of the effect of Lorentz and Moffatt profiles on the accuracy ofasteroids positions determining by the observation from SBG AO UFU.

  2. Hydrogen Sorption and Transport

    NASA Astrophysics Data System (ADS)

    McNeece, C. J.; Hesse, M. A.

    2015-12-01

    Hydrogen is unique among aqueous ions, both in its importance for geochemical reactions, and in its complex transport behavior through reactive media. The structure of hydrogen reaction fronts can be analyzed in the advective limit of the transport equation. At local chemical equilibrium, sorption of hydrogen onto the media surface (sorption isotherm) controls reaction front morphology. Transport modeling thus necessitates accurate knowledge of surface chemistry. Though motivated by transport, sorption models are often parameterized against batch titration experiments. The validity of these parameterizations, in a transport setting, are seldom tested. The analytic solution to the transport equation gives an algebraic relationship between concentration velocity and equilibrium sorption behavior. In this study, we conduct a suite of column flow experiments through quartz sand. Hydrogen concentration breakthrough curves at the column outlet are used to infer the "transport sorption isotherm." These results are compared to the batch titration derived sorption isotherm. We find excellent agreement between the datasets. Our findings suggest that, for aqueous hydrogen, local chemical equilibrium is a valid assumption. With the goal of a predictive transport model, we parameterize various sorption models against this dataset. Models which incorporate electrostatic effects at the surface predict transport well. Nonelectrostatic models such as the Kd, Langmuir, and Freundlich models fail. These results are particularly compelling as nonelectrostatic models are often employed to predict hydrogen transport in many reactive transport code.

  3. Using the Fingerprinting Method to Customize RTLS Based on the AoA Ranging Technique

    PubMed Central

    Jachimczyk, Bartosz; Dziak, Damian; Kulesza, Wlodek J.

    2016-01-01

    Real-time Locating Systems (RTLSs) have the ability to precisely locate the position of things and people in real time. They are needed for security and emergency applications, but also for healthcare and home care appliances. The research aims for developing an analytical method to customize RTLSs, in order to improve localization performance in terms of precision. The proposed method is based on Angle of Arrival (AoA), a ranging technique and fingerprinting method along with an analytically defined uncertainty of AoA, and a localization uncertainty map. The presented solution includes three main concerns: geometry of indoor space, RTLS arrangement, and a statistical approach to localization precision of a pair of location sensors using an AoA signal. An evaluation of the implementation of the customized RTLS validates the analytical model of the fingerprinting map. The results of simulations and physical experiments verify the proposed method. The research confirms that the analytically established fingerprint map is the valid representation of RTLS’ performance in terms of precision. Furthermore, the research demonstrates an impact of workspace geometry and workspace layout onto the RTLS’ performance. Moreover, the studies show how the size and shape of a workspace and the placement of the calibration point affect the fingerprint map. Withal, the performance investigation defines the most effective arrangement of location sensors and its influence on localization precision. PMID:27314354

  4. Using the Fingerprinting Method to Customize RTLS Based on the AoA Ranging Technique.

    PubMed

    Jachimczyk, Bartosz; Dziak, Damian; Kulesza, Wlodek J

    2016-06-14

    Real-time Locating Systems (RTLSs) have the ability to precisely locate the position of things and people in real time. They are needed for security and emergency applications, but also for healthcare and home care appliances. The research aims for developing an analytical method to customize RTLSs, in order to improve localization performance in terms of precision. The proposed method is based on Angle of Arrival (AoA), a ranging technique and fingerprinting method along with an analytically defined uncertainty of AoA, and a localization uncertainty map. The presented solution includes three main concerns: geometry of indoor space, RTLS arrangement, and a statistical approach to localization precision of a pair of location sensors using an AoA signal. An evaluation of the implementation of the customized RTLS validates the analytical model of the fingerprinting map. The results of simulations and physical experiments verify the proposed method. The research confirms that the analytically established fingerprint map is the valid representation of RTLS' performance in terms of precision. Furthermore, the research demonstrates an impact of workspace geometry and workspace layout onto the RTLS' performance. Moreover, the studies show how the size and shape of a workspace and the placement of the calibration point affect the fingerprint map. Withal, the performance investigation defines the most effective arrangement of location sensors and its influence on localization precision.

  5. Correction of shortening and/or angular deformities by distraction osteogenesis using AO-tubular fixator.

    PubMed

    Sangkaew, Chanchit

    2003-01-01

    Eighteen patients (20 bony segments) who had shortening and/or angular deformities were treated by distraction osteogenesis using AO-tubular external fixator. The mean angular correction was 18.9 degrees (range, 8-40 degrees). Of the group in whom shortening and angulation was corrected, the mean length gained was 4.2 cm (3-6 cm). The mean treatment time was 4.9 months (range, 2-13 months) and the mean follow-up was 12 months after removal of the fixator (range, 3-30 months). Delayed union with loosening of the fixator occurred in one patient which resulted in residual shortening of 1.5 cm. The author's technique of distraction osteogenesis using AO-tubular fixator with the new distraction rate of 1 mm/48 h (1 mm/step) could adequately correct shortening and/or angular deformities. No extra equipment was needed other than the readily-available AO-tubular fixation systems. No serious complications such as neurovascular injury were encountered.

  6. AO modelling for wide-field E-ELT instrumentation using Monte-Carlo simulation

    NASA Astrophysics Data System (ADS)

    Basden, Alastair; Morris, Simon; Morris, Tim; Myers, Richard

    2014-08-01

    Extensive simulations of AO performance for several E-ELT instruments (including EAGLE, MOSAIC, HIRES and MAORY) have been ongoing using the Monte-Carlo Durham AO Simulation Package. We present the latest simulation results, including studies into DM requirements, dependencies of performance on asterism, detailed point spread function generation, accurate telescope modelling, and studies of laser guide star effects. Details of simulations will be given, including the use of optical models of the E-ELT to generate wave- front sensor pupil illumination functions, laser guide star modelling, and investigations of different many-layer atmospheric profiles. We discuss issues related to ELT-scale simulation, how we have overcome these, and how we will be approaching forthcoming issues such as modelling of advanced wavefront control, multi-rate wavefront sensing, and advanced treatment of extended laser guide star spots. We also present progress made on integrating simulation with AO real-time control systems. The impact of simulation outcomes on instrument design studies will be discussed, and the ongoing work plan presented.

  7. AOS: adaptive offset time scheduling for TCP fairness in optical burst-switched network

    NASA Astrophysics Data System (ADS)

    Zheng, Hongyun; Zhao, Yongxiang; Chen, Changjia

    2005-11-01

    Optical Burst-switched (OBS) is a promising switching technology and expected to support the future Internet backbone with dramatically increasing bandwidth demand. In an OBS network, burst contention causes burst loss due to bufferless nature of OBS core network. This kind of burst loss will interact with the above TCP layer. In this paper, we study the impact of this interaction on TCP fairness. We find significant unfairness among TCP flows that share the OBS core network, i.e. one flow obtains higher throughput while any others with much lower throughputs. The cause is the phenomenon called "the bigger eats the smaller (BES)", in which a TCP flow with higher rate occasionally will "see" less burst contentions and increase its rate further, while a TCP with lower rate will see more burst contentions and decrease its rate continually. Discuss a simple model to explain BES and verify that a continuous sequence of bursts will enhance BES. Then observe that offset time will be a good choice to control TCP fairness by a curve of unfairness control with offset time adjustment. Finally an adaptive offset time scheduling (AOS) algorithm is proposed. AOS assigns burst offset time value adaptive to the rate of TCP flow. The simulation results show that the fairness can be significantly improved by our AOS scheme.

  8. New classification system for long-bone fractures supplementing the AO/OTA classification.

    PubMed

    Garnavos, Christos; Kanakaris, Nikolaos K; Lasanianos, Nikolaos G; Tzortzi, Paraskevi; West, Robert M

    2012-05-01

    This article describes a novel, clinically oriented classification system for long-bone fractures that is simple, reliable, and useful to predict treatment method, complications, and outcome. The reliability and memorability of the new classification were statistically tested and compared with the AO-Müller/Orthopaedic Trauma Association (AO/OTA) long-bone fracture classification. The proposed classification system was also clinically validated with a targeted pilot study designed for content and clinical outcome retrospectively reviewing 122 closed tibial shaft fractures, which were used as a representative paradigm of long-bone fractures. Statistical evaluation showed that the proposed classification system had improved inter- and intraobserver variation agreement and easier memorability compared with the AO/OTA classification system. The clinical validation study showed its predictive value regarding selection of treatment method, complication rate, and injury outcome.The proposed classification system proved simple, reliable, and memorable. Its clinical value appeared strong enough to justify the organization of larger studies for a complete assessment of its clinical usefulness for all long-bone fractures.

  9. Integration, tests and laboratory performance of SAXO, the VLT-SPHERE extreme AO system

    NASA Astrophysics Data System (ADS)

    Petit, C.; Fusco, T.; Sauvage, J.-F.; Sevin, A.; Suarez, M.; Charton, J.; Baudoz, P.; Beuzit, J.-L.; Buey, T.; Dohlen, K.; Feautrier, P.; Fedrigo, E.; Fleuzry, B.; Gach, J.-L.; Hubin, N.; Kasper, M.; Mouillet, D.; Perret, D.; Puget, P.; Sinquin, J.-C.; Soenke, C.; Wildi, F.

    2011-09-01

    Direct detection and spectral characterization of extra-solar planets is one of the most exciting but also one of the most challenging areas in modern astronomy due to the very large contrast between the host star and the planet at very small angular separations. SPHERE (Spectro-Polarimetric High-contrast Exoplanet Research in Europe) is a second-generation instrument for the ESO VLT dedicated to this scientific objective. It combines an extreme adaptive optics system, various coronagraphic devices and a suite of focal instruments providing imaging, integral field spectroscopy and polarimetry capabilities in the visible and near-infrared spectral ranges. The extreme AO system, SAXO, is the heart of the SPHERE system, providing to the scientific instruments a flat wavefront corrected from all the atmospheric turbulence and internal defects. We will present a status of SAXO assembly integration and performance. The main requirements and system characteristics will be recalled, then each sub system will be individually presented and fully characterized and finally the full AO loop performance will be quantified. It will be demonstrated that SAXO will meet its challenging requirements (more than 90% of SR in H band with a residual jitter lower than 3 milli-arcseconds for average observation conditions on the VLT). Thanks to a coronagraphic analysis of the AO residuals, a detailed comparison between actual and simulated residual intensity profiles will be provided and will help to adjust the expected performance of the SPHERE system on sky, knowing that its first light is foreseen for mid 2012.

  10. SCExAO: the most complete instrument to characterize exoplanets and stellar environments

    NASA Astrophysics Data System (ADS)

    Lozi, Julien; Guyon, Olivier; Jovanovic, Nemanja; Singh, Garima; Doughty, Danielle; Pathak, Prashant; Goebel, Sean; Kudo, Tomoyuki

    2015-12-01

    The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument, currently under development for the Subaru Telescope, optimally combines state-of-the-art technologies to directly study exoplanets and stellar environments at the diffraction limit, both in visible and infrared light (0.6 to 2.4 um). The instrument already includes an ultra-fast visible pyramid wavefront sensor operating at 3.5 kHz, a 2k-actuator deformable mirror, a set of optimal coronagraphs that can work as close as 1 l/D, a low-order wavefront sensor, a high-speed speckle control, and two visible interferometric modules, VAMPIRES and FIRST. Stability of the wavefront correction has already been demonstrated on sky, and SCExAO is already producing scientific results. After the integration of the Integral Field Spectrograph (IFS) CHARIS and a Microwave Kinetic Inductance Detector (MKID) in 2016, SCExAO will be one of the most powerful and effective tools for characterizing exoplanets and disks.

  11. Microwelding of various metallic materials under ultravacuum (AO 138-10)

    NASA Technical Reports Server (NTRS)

    Assie, Jean Pierre; Conde, Eric

    1991-01-01

    The first finding from the AO 138-10 is that cold welding never occurred, and that microwelds didn't even affect the reference (presumably microweld prone) pairs of metals consisting of gold, silver, and chromium. The scientific disappointment from these results must be tempered by the notion of a static AO 138-10 experiment, reflecting the passive character of the global Long Duration Exposure Facility (LDEF) flight. Thus far, it has been theorized that cold welding results from the peeling of the oxide layer, that is formed in an earth environment, by the space environment since such a layer no longer grows in space. In fact, such stripping of the oxide layer supposes relative motion of the contacting materials. In the absence of such motion, as in this experiment, oxidation will preserve its integrity and continue to prevent microwelding. More bewildering is that there was no microwelding of the reference pairs. Even though AO 138-10 failed scientific expectations, as did the LDEF structure with cold welding, the positive, functional aspect to keep in mind is the safe operation of single-shot (appendage releasing and/or latching) mechanisms, unhindered by microwelding in a space vacuum, as now demonstrated by the statically representative pairs of materials. Other aspects of the experiment are discussed.

  12. PHOTOMETRIC EVOLUTION OF SNe Ib/c 2004ao, 2004gk, AND 2006gi

    SciTech Connect

    Elmhamdi, Abouazza; Kordi, Ayman; Tsvetkov, Dmitry; Danziger, I. John

    2011-04-20

    Photometric observations of three core collapse supernovae (SNe 2004ao, 2004gk, and 2006gi), covering about 200 days of evolution, are presented and analyzed. The photometric behavior of the three objects is consistent with their membership in the envelope-stripped Type Ib/c class. Pseudobolometric light curves are constructed. The corresponding measured e-folding times are found to be faster compared to the {sup 56}Co decay (i.e., 111.3 days), suggesting that a proportion of {gamma}-rays increasing with time have escaped without thermalization, owing to the low-mass nature of the ejecta. SN 2006gi has almost identical post-maximum decline phase luminosities as SN 1999ex and found to be similar to both SNe 1999dn and 1999ex in terms of the quasi-bolometric shape, placing it among the fast decliner Ib objects. SN 2004ao appears to fit within the slow decliner Ib SNe. SNe 2004ao and 2004gk display almost identical luminosities in the [50-100] day time interval, similar to SN 1993J. A preliminary simplified {gamma}-ray deposition model is described and applied to the computed pseudobolometric light curves, allowing one to find a range in the ejecta and {sup 56}Ni masses. The optical and quasi-bolometric light curves and the B - V color evolution of SN 2004gk are found to show a sudden drop after day 150. Correlating this fact to dust formation is premature and requires further observational evidence.

  13. Urban public transport today

    SciTech Connect

    Simpson, B. )

    1994-01-01

    It is widely recognized that there are many people for whom public transport is essential, particularly among the elderly, children and teenagers. Less obvious is the dependence of our cities for their existence on high capacity public transport. Although there is still a prevalent view that local public transport is only for those who do not have a car, we are slowly beginning to realize that we need to find ways of restricting use of the private car more severely and that will involve some transfer to public transport. Urban Public Transport Today gives an honest appraisal of the pros and cons of new public transport technologies. It shows how public transport can be made a less unacceptable alternative to the private car than it is now.

  14. Transportation System Requirements Document

    SciTech Connect

    Not Available

    1993-09-01

    This Transportation System Requirements Document (Trans-SRD) describes the functions to be performed by and the technical requirements for the Transportation System to transport spent nuclear fuel (SNF) and high-level radioactive waste (HLW) from Purchaser and Producer sites to a Civilian Radioactive Waste Management System (CRWMS) site, and between CRWMS sites. The purpose of this document is to define the system-level requirements for Transportation consistent with the CRWMS Requirement Document (CRD). These requirements include design and operations requirements to the extent they impact on the development of the physical segments of Transportation. The document also presents an overall description of Transportation, its functions, its segments, and the requirements allocated to the segments and the system-level interfaces with Transportation. The interface identification and description are published in the CRWMS Interface Specification.

  15. Transportation safety training

    SciTech Connect

    Jones, E.

    1990-01-01

    Over the past 25 years extensive federal legislation involving the handling and transport of hazardous materials/waste has been passed that has resulted in numerous overlapping regulations administered and enforced by different federal agencies. The handling and transport of hazardous materials/waste involves a significant number of workers who are subject to a varying degree of risk should an accident occur during handling or transport. Effective transportation training can help workers address these risks and mitigate them, and at the same time enable ORNL to comply with the federal regulations concerning the transport of hazardous materials/waste. This presentation will outline how the Environmental and Health Protection Division's Technical Resources and Training Section at the Oak Ridge National Laboratory, working with transportation and waste disposal personnel, have developed and implemented a comprehensive transportation safety training program to meet the needs of our workers while satisfying appropriate federal regulations. 8 refs., 3 tabs.

  16. [Fructose transporter in yeasts].

    PubMed

    Lazar, Zbigniew; Dobrowolski, Adam; Robak, Małgorzata

    2014-01-01

    Study of hexoses transporter started with discovery of galactose permease in Saccharomyces cerevisiae. Glucose, fructose and mannose assimilation is assumed by numerous proteins encoded by different genes. To date over 20 hexoses transporters, belonging to Sugar Porter family and to Major Facilitator Superfamily, were known. Genome sequence analysis of Candida glabrata, Kluyveromyces lactis, Yarrowia lipolytica, S. cerevisaie and Debaryomyces hansenii reveled potential presence of 17-48 sugar porter proteins. Glucose transporters in S. cerevisiae have been already characterized. In this paper, hexoses transporters, responsible for assimilation of fructose by cells, are presented and compared. Fructose specific transporter are described for yeasts: Zygosaccharomyces rouxii, Zygosaccharomyces bailli, K. lactis, Saccharomyces pastorianus, S. cerevisiae winemaking strain and for fungus Botritys cinerea and human (Glut5p). Among six yeasts transporters, five are fructose specific, acting by facilitated diffusion or proton symport. Yeasts monosaccharides transporter studies allow understanding of sugars uptake and metabolism important aspects, even in higher eukaryotes cells.

  17. Improving Laser-Guide Star AO Observations via Mesospheric Sodium Enhancement

    NASA Astrophysics Data System (ADS)

    Whiteley, R.; Yavorski, J.; Jelks, C.; Colburn, W.; Berner, K.

    The use of modern Adaptive Optics (AO) systems allows large telescopes to approach diffraction limited seeing. This technique can improve the imaging resolution of a large telescope by more than an order of magnitude. Such a capability provides real improvement in ground-based space situational awareness (SSA) observations. The drawback to current adaptive optics systems is that they only improve resolution over small imaging regions, sometimes as small as a few tens of arc seconds. Such small imaging regions limit the availability of suitable guide stars, which in turn limits the availability and duty cycle of an AO system. This limitation has led to the development of systems for producing artificial guide stars, which can be created along a line of sight coincident with that of the telescope. The most commonly used artificial guide stars are created by tuning a laser to the frequency of the Sodium D1/D2 line complex, and exciting sodium atoms in the Earth's mesosphere. The mesospheric sodium layer is exceptionally rarified, and has densities that vary diurnally, seasonally, and geographically. Our investigation centers on the use of sounding rockets to deliver substantial quantities of atomic sodium to the mesospheric layer. This direct enhancement of the sodium layer could increase the number of nights that laser-guide star AO observations could be performed, as well as increasing guide star brightness. These improvements should yield better AO wavefront correction and faster imaging frame rates. For the SSA application, these improvements will lead to more and better imaging opportunities. We will present a basic overview of the relevant mesospheric dynamics, with emphasis on sodium dwell times and replenishment rates. We will present several possible mechanisms for delivery and deployment of atomic sodium in the mesosphere, and demonstrate the trade-offs in their use. We will present a possible concept of operation for notional delivery systems. Finally, we

  18. SLC1 Glutamate Transporters

    PubMed Central

    Grewer, Christof; Gameiro, Armanda; Rauen, Thomas

    2014-01-01

    The plasma membrane transporters for the neurotransmitter glutamate belong to the solute carrier 1 (SLC1) family. They are secondary active transporters, taking up glutamate into the cell against a substantial concentration gradient. The driving force for concentrative uptake is provided by the cotransport of Na+ ions and the countertransport of one K+ in a step independent of the glutamate translocation step. Due to eletrogenicity of transport, the transmembrane potential can also act as a driving force. Glutamate transporters are expressed in many tissues, but are of particular importance in the brain, where they contribute to the termination of excitatory neurotransmission. Glutamate transporters can also run in reverse, resulting in glutamate release from cells. Due to these important physiological functions, glutamate transporter expression and, therefore, the transport rate, are tightly regulated. This review summarizes recent literature on the functional and biophysical properties, structure-function relationships, regulation, physiological significance, and pharmacology of glutamate transporters. Particular emphasis is on the insight from rapid kinetic and electrophysiological studies, transcriptional regulation of transporter expression, and reverse transport and its importance for pathophysiological glutamate release under ischemic conditions. PMID:24240778

  19. Energy and transport.

    PubMed

    Woodcock, James; Banister, David; Edwards, Phil; Prentice, Andrew M; Roberts, Ian

    2007-09-22

    We examine the links between fossil-fuel-based transportation, greenhouse-gas emissions, and health. Transport-related carbon emissions are rising and there is increasing consensus that the growth in motorised land vehicles and aviation is incompatible with averting serious climate change. The energy intensity of land transport correlates with its adverse health effects. Adverse health effects occur through climate change, road-traffic injuries, physical inactivity, urban air pollution, energy-related conflict, and environmental degradation. For the world's poor people, walking is the main mode of transport, but such populations often experience the most from the harms of energy-intensive transport. New energy sources and improvements in vehicle design and in information technology are necessary but not sufficient to reduce transport-related carbon emissions without accompanying behavioural change. By contrast, active transport has the potential to improve health and equity, and reduce emissions. Cities require safe and pleasant environments for active transport with destinations in easy reach and, for longer journeys, public transport that is powered by renewable energy, thus providing high levels of accessibility without car use. Much investment in major road projects does not meet the transport needs of poor people, especially women whose trips are primarily local and off road. Sustainable development is better promoted through improving walking and cycling infrastructures, increasing access to cycles, and investment in transport services for essential needs. Our model of London shows how increased active transport could help achieve substantial reductions in emissions by 2030 while improving population health. There exists the potential for a global contraction and convergence in use of fossil-fuel energy for transport to benefit health and achieve sustainability.

  20. EBS Radionuclide Transport Abstraction

    SciTech Connect

    J. Prouty

    2006-07-14

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport

  1. Transportation: Grade 8. Cluster IV.

    ERIC Educational Resources Information Center

    Calhoun, Olivia H.

    A curriculum guide for grade 8, the document is devoted to the occupational cluster "Transportation." It is divided into five units: surface transportation, interstate transportation, air transportation, water transportation, and subterranean transportation (the Metro). Each unit is introduced by a statement of the topic, the unit's…

  2. Payload transportation system study

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A standard size set of shuttle payload transportation equipment was defined that will substantially reduce the cost of payload transportation and accommodate a wide range of payloads with minimum impact on payload design. The system was designed to accommodate payload shipments between the level 4 payload integration sites and the launch site during the calendar years 1979-1982. In addition to defining transportation multi-use mission support equipment (T-MMSE) the mode of travel, prime movers, and ancillary equipment required in the transportation process were also considered. Consistent with the STS goals of low cost and the use of standardized interfaces, the transportation system was designed to commercial grade standards and uses the payload flight mounting interfaces for transportation. The technical, cost, and programmatic data required to permit selection of a baseline system of MMSE for intersite movement of shuttle payloads were developed.

  3. Uphill transport membrane electrodes

    SciTech Connect

    Uto, M.; Yoshida, H.; Sugawara, M.; Umezawa, Y.

    1986-07-01

    A new membrane electrode was constructed in which carrier-mediated uphill transport of analytes is incorporated. The electrode can boost selectively virtual concentration of specific analytes by uphill transport against their concentration gradient across a built-in liquid membrane into its inner filling solution, whose volume is purposely made very small. Cd(II), UO/sub 2//sup 2 +/, and Cu(II) ion uphill transport membrane electrodes constructed here as illustrative examples utilize three different types of input energies, i.e., complexation, concentration gradient, and redox, respectively, for uphill transport of each analyte. Voltammetric detections were demonstrated for Cd(II) and UO/sub 2//sup 2 +/ ion uphill transport electrodes, and a potentiometric detection for a Cu(II) ion uphill transport membrane electrode is also described in terms of fundamental behaviors and a possible use for a new type of electrochemical sensor.

  4. Integrated space transportation evolution

    NASA Technical Reports Server (NTRS)

    Huffaker, Frederick; Kelley, David

    1990-01-01

    The development of an evolutionary approach to a space transportation system to meet the needs of the Space Exploration Initiative and other earth orbital and planetary missions is discussed. Common architectures, a building block approach to space transportation elements, the development of alternative technologies are considered as essential steps to arriving at an integrated space transportation system. These aspects are addressed as they apply to both lunar and Mars technology.

  5. Transportation of hazardous materials

    NASA Astrophysics Data System (ADS)

    Johnson, Max

    1994-03-01

    The transportation of hazardous materials has steadily increased through out the past thirty years and will continue to grow through the end of the century. The development of advanced technology to track extremely dangerous shipments and provide immediate electronic load information is essential to both transportation and public safety agencies. Federal, state and local transportation and public safety agencies must have hazardous material transportation information in order to plan, train and equip responders to meet the identified threat. Tracking and identification technology must be consistent within and across state and international borders. The development and implementation of a strategy and technology will require federal, state and private industry coordination and financing.

  6. Space Transportation Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Liou, Meng-Sing; Stewart, Mark E.; Suresh, Ambady; Owen, A. Karl

    2001-01-01

    This report outlines the Space Transportation Propulsion Systems for the NPSS (Numerical Propulsion System Simulation) program. Topics include: 1) a review of Engine/Inlet Coupling Work; 2) Background/Organization of Space Transportation Initiative; 3) Synergy between High Performance Computing and Communications Program (HPCCP) and Advanced Space Transportation Program (ASTP); 4) Status of Space Transportation Effort, including planned deliverables for FY01-FY06, FY00 accomplishments (HPCCP Funded) and FY01 Major Milestones (HPCCP and ASTP); and 5) a review current technical efforts, including a review of the Rocket-Based Combined-Cycle (RBCC), Scope of Work, RBCC Concept Aerodynamic Analysis and RBCC Concept Multidisciplinary Analysis.

  7. Advanced space transportation systems

    NASA Technical Reports Server (NTRS)

    Disher, J. H.; Hethcoat, J. P.; Page, M. A.

    1981-01-01

    Projected growth in space transportation capabilities beyond the initial Space Shuttle is discussed in terms of earth-to-low-orbit launch vehicles as well as transportation beyond low orbit (orbit transfer vehicles). Growth versions of the Shuttle and heavy-lift derivatives of the Shuttle are shown conceptually. More advanced launch vehicle concepts are also shown, based on rocket propulsion or combinations of rocket and air-breathing propulsion. Orbit transfer vehicle concepts for personnel transport and for cargo transport are discussed, including chemical rocket as well as electric propulsion. Finally, target levels of capability and efficiencies for later time periods are discussed and compared with the prospective vehicle concepts mentioned earlier.

  8. Thermodynamics of ABC transporters.

    PubMed

    Zhang, Xuejun C; Han, Lei; Zhao, Yan

    2016-01-01

    ABC transporters form the largest of all transporter families, and their structural study has made tremendous progress over recent years. However, despite such advances, the precise mechanisms that determine the energy-coupling between ATP hydrolysis and the conformational changes following substrate binding remain to be elucidated. Here, we present our thermodynamic analysis for both ABC importers and exporters, and introduce the two new concepts of differential-binding energy and elastic conformational energy into the discussion. We hope that the structural analysis of ABC transporters will henceforth take thermodynamic aspects of transport mechanisms into account as well.

  9. UZ Colloid Transport Model

    SciTech Connect

    M. McGraw

    2000-04-13

    The UZ Colloid Transport model development plan states that the objective of this Analysis/Model Report (AMR) is to document the development of a model for simulating unsaturated colloid transport. This objective includes the following: (1) use of a process level model to evaluate the potential mechanisms for colloid transport at Yucca Mountain; (2) Provide ranges of parameters for significant colloid transport processes to Performance Assessment (PA) for the unsaturated zone (UZ); (3) Provide a basis for development of an abstracted model for use in PA calculations.

  10. WASTE PACKAGE TRANSPORTER DESIGN

    SciTech Connect

    D.C. Weddle; R. Novotny; J. Cron

    1998-09-23

    The purpose of this Design Analysis is to develop preliminary design of the waste package transporter used for waste package (WP) transport and related functions in the subsurface repository. This analysis refines the conceptual design that was started in Phase I of the Viability Assessment. This analysis supports the development of a reliable emplacement concept and a retrieval concept for license application design. The scope of this analysis includes the following activities: (1) Assess features of the transporter design and evaluate alternative design solutions for mechanical components. (2) Develop mechanical equipment details for the transporter. (3) Prepare a preliminary structural evaluation for the transporter. (4) Identify and recommend the equipment design for waste package transport and related functions. (5) Investigate transport equipment interface tolerances. This analysis supports the development of the waste package transporter for the transport, emplacement, and retrieval of packaged radioactive waste forms in the subsurface repository. Once the waste containers are closed and accepted, the packaged radioactive waste forms are termed waste packages (WP). This terminology was finalized as this analysis neared completion; therefore, the term disposal container is used in several references (i.e., the System Description Document (SDD)) (Ref. 5.6). In this analysis and the applicable reference documents, the term ''disposal container'' is synonymous with ''waste package''.

  11. [Recommendations for perinatal transport].

    PubMed

    Esqué Ruiz, M; Figueras Aloy, J; García Alix, A; Alomar Ribes, A; Blanco Bravo, D; Ferández Lorenzo, J R

    2001-08-01

    Perinatal transport should be integrated into a system of perinatal care within a regional health care program and should be planned according to the healthcare map of each community. We describe the various types of transport, their advantages and disadvantages, the resources required, and the protocol that should be followed in perinatal transfer. We highlight the importance of maternal and neonatal transport. The organization of transfers receives special attention, and we discuss the different functions of the coordinating, referral and receiving centers as well as those of the transport assistance team. We also discuss ethical-legal questions.

  12. Increasing Efficiency at the NTF by Optimizing Model AoA Positioning

    NASA Technical Reports Server (NTRS)

    Crawford, Bradley L.; Spells, Courtney

    2006-01-01

    The National Transonic Facility (NTF) at NASA Langley Research Center (LaRC) is a national resource for aeronautical research and development. The government, military and private industries rely on the capability of this facility for realistic flight data. Reducing the operation costs and keeping the NTF affordable is essential for aeronautics research. The NTF is undertaking an effort to reduce the time between data points during a pitch polar. This reduction is being driven by the operating costs of a cryogenic facility. If the time per data point can be reduced, a substantial cost savings can be realized from a reduction in liquid nitrogen (LN2) consumption. It is known that angle-of-attack (AoA) positioning is the longest lead-time item between points. In January 2005 a test was conducted at the NTF to determine the cause of the long lead-time so that an effort could be made to improve efficiency. The AoA signal at the NTF originates from onboard instrumentation then travels through a number of different systems including the signal conditioner, digital voltmeter, and the data system where the AoA angle is calculated. It is then fed into a closed loop control system that sets the model position. Each process along this path adds to the time per data point affecting the efficiency of the data taking process. Due to the nature of the closed loop feed back AoA control and the signal path, it takes approximately 18 seconds to take one pitch pause point with a typical AoA increment. Options are being investigated to reduce the time delay between points by modifying the signal path. These options include: reduced signal filtering, using analog channels instead of a digital volt meter (DVM), re-routing the signal directly to the AoA control computer and implementing new control algorithms. Each of these has potential to reduce the positioning time and together the savings could be significant. These timesaving efforts are essential but must be weighed against

  13. LDEF (Prelaunch), AO135 : Effect of Space Exposure on Pyroelectric Infrared Detectors, Tray E05

    NASA Technical Reports Server (NTRS)

    1984-01-01

    LDEF (Prelaunch), AO135 : Effect of Space Exposure on Pyroelectric Infrared Detectors, Tray E05 The prelaunch photograph was taken in SAEF II at KSC prior to installation of the integrated tray on the LDEF. The Space Exposure on Pyroelectric Infrared Detectors Experiment (AO135) consist of twenty detectors of three different types of materials, lithium-tantalate, strontium-barium-niobate and triglycine-sulfide. The Pyroelectric infrered detector experiment is an integral part of the Active Optical System Component Experiment (S0050) that contains 136 test specimen and is located in a six (6) inch deep LDEF peripheral experiment tray. The experiment tray is divided into six sections, each consisting of a 1/4 inch thick chromic anodized aluminum base plate and a 1/16th inch thick aluminum hat shaped structure for mounting the test specimen. The test specimen are typi- cally placed in fiberglass-epoxy retainer strip assemblies prior to installation on the hat shaped mounting structure. Five of the six sections are covered by a 1/8 inch thick anodized aluminum sun screen with openings that allowed 56 percent transmission over the central region. Two subexperiments, The Optical Materials and UV Detectors Experiment (S0050-01) consist of 15 optical windows, filters and detectors and occupies one of the trays six sub-sections and The Optical Substrates and Coatings Experiment (S0050-02 ) that includes 12 substrates and coatings and a secondary experiment, The Holographic Data Storage Crystal Experiment (AO044) with four crystals, are also mounted in the integrated tray. The experiment structure was assembled with non-magnetic stainless steel fasteners.

  14. AO fixateur interne in treating burst fractures of the thoracolumbar spine.

    PubMed

    Liu, C L; Wang, S T; Lin, H J; Kao, H C; Yu, W K; Lo, W H

    1999-09-01

    A burst fracture of the thoracolumbar junction is an unstable spinal fracture, which is caused by high-energy trauma. There are many methods of treatment, both surgical and nonsurgical, in dealing with spinal burst fractures. The Arbeitsgemeinschaft für Osteosynthesefragen (AO) Fixateur Interne (FI) system was introduced in 1985 for posterior spine surgery with a transpedicular screw system. From April, 1989, through December, 1994, we encountered 42 patients with 42 acute burst fractures of the spine; 26 were male and 16 were female, with an average age of 41.2 years. One fracture occurred on T11, seven on T12, 16 on L1, 11 on L2, one on L3, four on L4 and two on L5. According to the Denis classification, there were eight type A, 23 type B, five type C, three type D and three type E fractures. All of these patients received posterior reduction without decompression, posterior short segmental fixation with AO FI instrumentation and posterior fusion. After follow-up for an average of 66.1 months, all fractures were found to have united with residual back pain in only six patients; five patients, including one with nonunion, had back pain without the necessity of medication, and the other one had occasional back pain that was well controlled by medication. The immediate postoperative Cobb's angle improved by an average of 14.2 degrees, and there was an average loss of 3.3 degrees at final follow-up. All patients were neurologically intact at final follow-up except two patients, who were Frankel D. Seven patients had complications during follow-up; one experienced nonunion; four experienced screw breakage, one had screw pullout, and the other experienced breakage of the connecting rod. From our retrospective study, the outcome of burst fracture of the spine treated with AO FI instrumentation system was satisfactory.

  15. Development and validation of the AO pediatric comprehensive classification of long bone fractures by the Pediatric Expert Group of the AO Foundation in collaboration with AO Clinical Investigation and Documentation and the International Association for Pediatric Traumatology.

    PubMed

    Slongo, Theddy; Audigé, Laurent; Schlickewei, Wolfgang; Clavert, Jean-Michel; Hunter, James

    2006-01-01

    A series of four agreement studies (classification sessions) were conducted to support the development and validation of a comprehensive pediatric long bone fracture classification system. This system follows the principle of the Müller-AO classification for long bones in adults and integrates most relevant existing pediatric classification systems. The diagnosis includes the distinction between epiphyseal (E), metaphyseal (M), or diaphyseal (D) fractures, as well as identification of child-specific features. This article describes the proposed system in some detail. Digital standard preoperative anteroposterior and lateral radiographs from 267 consecutive pediatric patients (<16 years old and open physis) with single fractures of the distal humerus, radius, or tibia were collected at a single university children's hospital. Fractures were classified independently by five experienced pediatric surgeons. The classification process was assessed for reliability using the kappa coefficient and accuracy using latent class modeling separately for each bone for bone type, and separately for each bone type for child codes. At the last classification session, kappa values for E-M-D and child code classifications were mostly above 0.90, and accuracy estimates were between 75% and 100% for different surgeons, types, and bones. Disagreement and misclassification of fractures were overall very low; hence, experienced and trained surgeons can classify pediatric long bone fractures using the proposed system with high accuracy based on standard radiographic views. The authors encourage wide consultation and further evaluation of this proposed pediatric long bone classification system with a larger number of future users with different training before being used for documentation and clinical studies.

  16. Rayleigh guide star AO demonstrator for the 4.2m William Herschel Telescope

    NASA Astrophysics Data System (ADS)

    Clark, Paul; Bissonauth, Nirmal; O'Byrne, John W.; Dunlop, Colin N.; Gregory, Thomas; Morris, Timothy J.; Myers, Richard M.; Saunter, Christopher D.; Wilson, Richard W.

    2003-02-01

    An experimental Adaptive Optics system utilizing a low-altitude Rayleigh Laser Guide Star is presented. The current status of the project is described together with plans for future work, with the ultimate goal of providing demonstration Rayleigh LGS AO science on the 4.2m William Herschel Telescope. The implementation of the demonstration system is described in detail as are the technical challenges encountered during the development of the current shared-launch based system. Other papers in this conference describe a proposal for a facility class LGS system for the WHT and the performance of the observatory's NAOMI adaptive optics system.

  17. Using DARC in a multi-object AO bench and in a dome seeing instrument

    NASA Astrophysics Data System (ADS)

    Sáez, Norman; Basden, Alistair; Guzmán, Dani; Dubost, Nicolás.; Berdja, Amokrane

    2014-07-01

    The Durham adaptive Optics Real Time Controller (DARC)1 is a real-time system for astronomical adaptive optics systems originally developed at Durham University and in use for the CANARY instrument. One of its main strengths is to be a generic and high performance real-time controller running on an off-the-shelf Linux computer. We are using DARC for two different implementations: BEAGLE,2 a Multi-Object AO (MOAO) bench system to experiment with novel tomographic reconstructors and LOTUCE2,3 an in-dome turbulence instrument. We present the software architecture for each application, current benchmarks and lessons learned for current and future DARC developers.

  18. On random walk de Lévy aplicado aos mapas de variâncias

    NASA Astrophysics Data System (ADS)

    Klafke, J. C.

    2003-08-01

    Uma pergunta que surge ao nos confrontarmos com os mapas de variâncias, ou s-Maps [Klafke, J. C. "Estudo da Difusão Caótica em Ressonâncias Asteroidais", Tese de Doutorado, IAG/USP, 2002] diz respeito ao conteúdo físico de tais representações do espaço de fase. Ou seja, o que representa as variâncias das ações obtidas para uma determinada condição inicial e como relacioná-las com o tempo de difusão das órbitas, supondo-se que estas de fato estejam envolvidas em um processo difusivo? Para discutirmos essa questão, lançamos mão da modelagem dos processos estocásticos subjacentes às variâncias determinadas e implementamos uma série de simulações do tipo Monte Carlo a partir das informações registradas nos s-Maps calculados para algumas ressonâncias asteroidais bem estudadas (p.ex. 3: 1, 2: 1 e 3: 2). Para tanto, temos usado uma função de densidade de probabilidade gaussiana ao definir os n passos que permitirão estabelecer uma relação direta entre o Mapa de Difusão e o Mapa de Variâncias. Contudo, os resultados obtidos até agora tem subestimado o tempo de difusão esperado para os fenômenos conhecidos. Tal se deve ao fato de que, no processo difusivo real, é possível existirem passos de comprimento consideravelmente maiores que a média estabelecida pelas distribuições gaussiana ou normal, sobretudo quando se cruza uma região caótica. Neste trabalho, apresentamos os resultados comparativos de simulações de Monte Carlo com base no random walk de Lévy [Klafter, J. et al. 2002. "Beyond Brownian motion", Phys. Today, Feb, 33-39.], o qual possibilita passos esporádicos de comprimento acima do valor médio (saltos) permitindo estabelecer uma escala de tempo mais próxima da esperada para a difusão.

  19. Tomographic separation of composite spectra - The components of the O-star spectroscopic binary AO Cassiopeiae

    NASA Technical Reports Server (NTRS)

    Bagnuolo, William G., Jr.; Gies, Douglas R.

    1991-01-01

    The UV photospheric lines of the short-period, double-lined O-star spectroscopic binary AO Cas are analyzed. Archival data from IUE (16 spectra uniformly distributed in orbital phase) were analyzed with a tomography algorithm to produce the separate spectra of the two stars in six spectral regions. The spectral classifications of the primary and secondary, O9.5 III and O8 V, respectively, were estimated through a comparison of UV line ratios with those in spectral standard stars. An intensity ratio of 0.5-0.7 (primary brighter) at 1600 A is compatible with the data.

  20. The adaptive optics modes for HARMONI: from Classical to Laser Assisted Tomographic AO

    NASA Astrophysics Data System (ADS)

    Neichel, B.; Fusco, T.; Sauvage, J.-F.; Correia, C.; Dohlen, K.; El-Hadi, K.; Blanco, L.; Schwartz, N.; Clarke, F.; Thatte, N. A.; Tecza, M.; Paufique, J.; Vernet, J.; Le Louarn, M.; Hammersley, P.; Gach, J.-L.; Pascal, S.; Vola, P.; Petit, C.; Conan, J.-M.; Carlotti, A.; Vérinaud, C.; Schnetler, H.; Bryson, I.; Morris, T.; Myers, R.; Hugot, E.; Gallie, A. M.; Henry, David M.

    2016-07-01

    HARMONI is a visible and NIR integral field spectrograph, providing the E-ELT's core spectroscopic capability at first light. HARMONI will work at the diffraction limit of the E-ELT, thanks to a Classical and a Laser Tomographic AO system. In this paper, we present the system choices that have been made for these SCAO and LTAO modules. In particular, we describe the strategy developed for the different Wave-Front Sensors: pyramid for SCAO, the LGSWFS concept, the NGSWFS path, and the truth sensor capabilities. We present first potential implementations. And we asses the first system performance.

  1. Optical Photometry of the flaring gamma-ray blazar AO 0235+164

    NASA Astrophysics Data System (ADS)

    Pursimo, Tapio; Losada, Illa R.; Messa, Matteo; Gafton, Emanuel; Ojha, Roopesh

    2016-03-01

    We report optical photometry of the blazar AO 0235+164 obtained with the 2.56m Nordic Optical Telescope in La Palma to look for any enhanced optical activity associated with a recent flare in the daily averaged gamma-ray flux seen in the public lightcurve of the Fermi/LAT instrument: http://fermi.gsfc.nasa.gov/FTP/glast/data/lat/catalogs/asp/current/lightcurves/0235+164_86400.png Fermi/LAT first reported a detection of gamma-ray activity from this source in Sep, 2008 (ATel#1744) and a short timescale flare in Oct 14, 2008 (ATel#1784).

  2. LDEF (Prelaunch), AO187-01 : The Chemistry of Micrometeoroids, Tray A03

    NASA Technical Reports Server (NTRS)

    1984-01-01

    LDEF (Prelaunch), AO187-01 : The Chemistry of Micrometeoroids, Tray A03 The prelaunch photograph shows the two (2) clam shell type canisters in their closed position. The canister shells are made of aluminum sheet material with end caps of diecast aluminum. The baseplate and support structure are fabricated from 6000 series aluminum. Fasteners are non-magnetic stainless steel. The electrical box and the stainless steel tubing located on the baseplate protect the drive system wiring. The experiment contains a timing mechanism that provides the intelligence to open the canisters after the Orbiter has departed the area and any initial outgassing or offgassing has occurred.

  3. Preliminary results from the chemistry of micrometeoroid experiment (AO 187-1)

    NASA Technical Reports Server (NTRS)

    Horz, Friedrich; Bernhard, R. P.; See, Thomas H.; Warren, J.; Brownlee, Don E.; Laurance, M.

    1991-01-01

    The purpose of experiment AO 187-1 was to expose high purity substrates of suitable cratering properties to obtain detailed crater statistics that may be converted into projectile masses and fluxes and to chemically characterize as many impactors as possible. The latter information would hopefully reveal distinct classes of natural and man-made particles in low-Earth orbit. It was found that crater that yield residues show that natural and man-made impactors may be differentiated and that diversity exists within each group. 'Chondritic' compositions dominate among natural particles, yet some craters contain unmelted fragments of minerals (Olivine and pyroxene).

  4. COMPASS: an efficient, scalable and versatile numerical platform for the development of ELT AO systems

    NASA Astrophysics Data System (ADS)

    Gratadour, D.; Puech, M.; Vérinaud, C.; Kestener, P.; Gray, M.; Petit, C.; Brulé, J.; Clénet, Y.; Ferreira, F.; Gendron, E.; Lainé, M.; Sevin, A.; Rousset, G.; Hammer, F.; Jégouzo, I.; Paillous, Michele; Taburet, S.; Yang, Y.; Beuzit, J.-L.; Carlotti, A.; Westphal, M.; Epinat, B.; Ferrari, M.; Gautrais, T.; Lambert, J. C.; Neichel, B.; Rodionov, S.

    2014-08-01

    The main objective of the COMPASS project is to provide a full scale end-to-end AO development platform, able to address the E-ELT scale and designed as a free, open source numerical tool with a long term maintenance plan. The development of this platform is based on a full integration of software with hardware and relies on an optimized implementation on heterogeneous hardware using GPUs as accelerators. In this paper, we present the overall platform, the various work packages of this project, the milestones to be reached, the results already obtained and the first output of the ongoing collaborations.

  5. An overview of the first results on the solar array passive LDEF experiment (sample), AO171

    NASA Technical Reports Server (NTRS)

    Whitaker, Ann F.; Young, Leighton E.

    1991-01-01

    Space environmental effects were visibly obvious on components of experiment AO171 which contained solar cells, composites, polymeric thin films, solar reflectors, protective coatings, metals, paints , and elastomers. Micrometeoroid/space debris impacts were observed on all experiment elements. Luminescence of polyimide, silicone, and polyurethane materials occurred under black light examination. Outgassing of RTV511 occurred mainly as a result of insufficient thermal vacuum bakeout. Solar cell degradation was predominantly below 10 percent. Elastomers lost mass and discolored; composites showed evidence of atomic oxygen attack, and unprotected thin polymer films eroded away.

  6. Direct hip joint distraction during acetabular fracture surgery using the AO universal manipulator.

    PubMed

    Calafi, L Afshin; Routt, M L Chip

    2010-02-01

    Certain acetabular fractures may necessitate distraction of the hip joint for removal of intra-articular debris and assessment of reduction. Distraction can be accomplished by manual traction, using a traction table or an AO universal manipulator (UM). The UM is a relatively simple and an inexpensive device that can provide focal distraction in a controlled manner without the risks associated with the use of a traction table. We describe a technique using the UM for hip joint distraction during acetabular fracture surgery through a Kocher-Langenbeck surgical exposure.

  7. Monitoring Io volcanism with AO telescopes during and after the NH flyby

    NASA Astrophysics Data System (ADS)

    Marchis, F.; Spencer, J. R.; Lopes, R. M.; Davies, A. G.; Dumas, C.

    2007-12-01

    To support the New Horizons (NH) Jupiter encounter we monitored Io's volcanic activity using high angular resolution images in the near infrared (1-5 microns) provided by adaptive optics (AO) systems available on 8-10m class telescopes. We initiated the campaign on Feb. 25 2007 with data obtained with the VLT-Yepun telescope (ESO, Paranal, Chile), just before NH closest approach. We continued monitoring with the Gemini North telescope (Hawaii, USA). The last observation was taken on May 28 2007. Numerous active volcanoes are visible in the data but the Tvashtar eruption is by far the most energetic. Extremely high angular resolution data from NH revealed fine detail of the eruption, such as the presence of an active plume [1]. This volcano has an interesting past history. It was seen as a powerful eruption from Nov. 26 1999 during the Galileo I25 [2] flyby to Feb. 19 2001 from the ground [3]. It was dormant or below our ground-based limit of detection (T<330 K assuming an area of 460 km2) between Dec 2001 and May 2004 [4,5]. The re-awakening of the volcano was reported by Laver et al. [6] in April 2006 based on Keck Adaptive Optics (AO) observations. Our last Gemini AO observation taken on May 26 shows that Tvashtar was still very active. Based on the previous behavior of this volcano [7] it is very likely that the activity reported in 2007 is a continuation of the Tvashtar-2006 eruption. Other hot spots, such as Loki Patera, Pele, and a new hot spot located north of Loki Patera, were seen in our data. We will describe the global picture of Io's volcanic activity derived from our observations, comparing it with previous observations from the Galileo spacecraft and using ground-based AO. 1. Spencer et al., AGU, this session, 2007 2. McEwen et al., Science, 288, 1193-1198, 2000 3. Marchis et al. Icarus, 160, 124-131, 2002 4. Marchis et al., Icarus, 176, 1, 2005 5. Marchis et al., AGU Fall meeting, V33C-1483, 2004 6. Laver et al., Icarus, in press, 2006 7. Milazzo et

  8. Future use of silicon photomultipliers for K AOS at MAMI and P¯ANDA at FAIR

    NASA Astrophysics Data System (ADS)

    Achenbach, P.; Lorente, A. Sanchez; Majos, S. Sánchez; Pochodzalla, J.

    2009-10-01

    A characterization of scintillating fibres with silicon photomultiplier read-out was performed in view of their possible application in fibre tracking detector systems. Such a concept is being considered for the K AOS spectrometer at the Mainz Microtron MAMI and as a time-of-flight start detector for the hypernuclear physics programme at the P¯ANDA experiment of the FAIR project. Results on particle detection efficiency and time resolution are discussed. In summary, the silicon devices are very suitable for the detection of the low light yield from scintillating fibres insofar a trigger scheme is found to cope with the noise rate characteristics.

  9. The AIROPA software package: milestones for testing general relativity in the strong gravity regime with AO

    NASA Astrophysics Data System (ADS)

    Witzel, Gunther; Lu, Jessica R.; Ghez, Andrea M.; Martinez, Gregory D.; Fitzgerald, Michael P.; Britton, Matthew; Sitarski, Breann N.; Do, Tuan; Campbell, Randall D.; Service, Maxwell; Matthews, Keith; Morris, Mark R.; Becklin, E. E.; Wizinowich, Peter L.; Ragland, Sam; Doppmann, Greg; Neyman, Chris; Lyke, James; Kassis, Marc; Rizzi, Luca; Lilley, Scott; Rampy, Rachel

    2016-07-01

    General relativity can be tested in the strong gravity regime by monitoring stars orbiting the supermassive black hole at the Galactic Center with adaptive optics. However, the limiting source of uncertainty is the spatial PSF variability due to atmospheric anisoplanatism and instrumental aberrations. The Galactic Center Group at UCLA has completed a project developing algorithms to predict PSF variability for Keck AO images. We have created a new software package (AIROPA), based on modified versions of StarFinder and Arroyo, that takes atmospheric turbulence profiles, instrumental aberration maps, and images as inputs and delivers improved photometry and astrometry on crowded fields. This software package will be made publicly available soon.

  10. B'NAI AO...alive, healthy and growing...a brief history.

    PubMed

    Williamowsky, Ben

    2006-03-01

    A daily minyan was held at 7:00 AM each morning at the recent Alpha Omega International Convention in Hollywood, Florida. That was Chanukah week, when a Torah reading is required. Thanks to a request by Allen Ressler, Torah reader, Rabbi Menachem Levy...who is connected local Chabad Congregation, joined us. As participants in the service crowded the designated prayer room, I was moved to reflect on how B'nai AO came about. At the suggestion of International Editor Dan Uditsky, I will share some facts, and especially my own personal memories.

  11. Transport characteristics of urea transporter-B.

    PubMed

    Yang, Baoxue

    2014-01-01

    UT-B represents the major urea transporter in erythrocytes, in addition to being expressed in kidney descending vasa recta, brain, spleen, ureter, bladder, and testis. Expression of urea transporter UT-B confers high urea permeability to mammalian erythrocytes. Erythrocyte membranes are also permeable to various urea analogues, suggesting common transport pathways for urea and structurally similar solutes. UT-B is highly permeable to urea and the chemical analogues formamide, acetamide, methylurea, methylformamide, ammonium carbamate, and acrylamide, each with a Ps > 5.0 × 10(-6) cm/s at 10 °C. The amides formamide, acetamide, acrylamide, and butyramide efficiently diffuse across lipid bilayers. The urea analogues dimethylurea, acryalmide, methylurea, thiourea, and methylformamide inhibit UT-B-mediated urea transport by >60 % by a pore-blocking mechanism. UT-B is also a water channel in erythrocytes and has a single-channel water permeability that is similar to aquaporin-1. Whether UT-B is an NH3 channel still needs further study. Urea permeability (Purea) in erythrocytes differs between different mammals. Carnivores (dog, fox, cat) exhibit high Purea. In contrast, herbivores (cow, donkey, sheep) show much lower Purea. Erythrocyte Purea in human and pig (omnivores) was intermediate. Rodents and lagomorphs (mouse, rat, rabbit) have Purea intermediate between carnivores and omnivores. Birds that do not excrete urea and do not express UT-B in their erythrocytes have very low values. In contrast to Purea, water permeability is relatively similar in all mammals studied. This chapter will provide information about the transporter characteristics of UT-B.

  12. Transport of sugars.

    PubMed

    Chen, Li-Qing; Cheung, Lily S; Feng, Liang; Tanner, Widmar; Frommer, Wolf B

    2015-01-01

    Soluble sugars serve five main purposes in multicellular organisms: as sources of carbon skeletons, osmolytes, signals, and transient energy storage and as transport molecules. Most sugars are derived from photosynthetic organisms, particularly plants. In multicellular organisms, some cells specialize in providing sugars to other cells (e.g., intestinal and liver cells in animals, photosynthetic cells in plants), whereas others depend completely on an external supply (e.g., brain cells, roots and seeds). This cellular exchange of sugars requires transport proteins to mediate uptake or release from cells or subcellular compartments. Thus, not surprisingly, sugar transport is critical for plants, animals, and humans. At present, three classes of eukaryotic sugar transporters have been characterized, namely the glucose transporters (GLUTs), sodium-glucose symporters (SGLTs), and SWEETs. This review presents the history and state of the art of sugar transporter research, covering genetics, biochemistry, and physiology-from their identification and characterization to their structure, function, and physiology. In humans, understanding sugar transport has therapeutic importance (e.g., addressing diabetes or limiting access of cancer cells to sugars), and in plants, these transporters are critical for crop yield and pathogen susceptibility.

  13. Transporting Students with Disabilities.

    ERIC Educational Resources Information Center

    Mawdsley, Ralph D.

    1998-01-01

    Under the 1973 Rehabilitation Act (Section 504) and the Individuals with Disabilities Education Act, school districts must transport students with disabilities to a site providing a free, appropriate education in the least restrictive environment. This article discusses federal and state laws governing student transportation, including wheelchair…

  14. Transportation and the handicapped

    NASA Technical Reports Server (NTRS)

    Richardson, H. H.

    1974-01-01

    Some statistics on the handicapped in relation to transportation are considered, and some of the major deterrents to travel in our existing systems are outlined. Some of the benefits of enhanced mobility are identified and examples are given of minimizing travel barriers. Finally, some of DOT's activities that are directed toward improving transportation for the handicapped are outlined.

  15. Conservation in transportation

    SciTech Connect

    1980-05-30

    A nationwide examination was made of grassroots energy conservation programs related to transportation. Information compiled from civic groups, trade associations, and corporations is included on driver awareness/mass transit; travel; and ride sharing. It is concluded that a willingness by the public to cooperate in transportation energy conservation exists and should be exploited. (LCL)

  16. Pupil Transportation Management.

    ERIC Educational Resources Information Center

    Miller, Anthony R.

    The safest means of transportation in the United States is the school bus fleet. Each school day, over 350,000 school buses transport about 22,000,000 children ages 3 to 21--from wheelchair pupils to varsity football players--to and from school in weather conditions ranging from those for Fairbanks, Alaska, to those typical of Cave Creek, Arizona.…

  17. Pupil Transportation Management.

    ERIC Educational Resources Information Center

    Miller, Anthony R.

    The safest means of transportation in the United States is the school bus fleet. Each school day, over 350,000 school buses transport about 22,000,000 children ages 3 to 21--from wheelchair pupils to varsity football players--to and from school in weather conditions ranging from those for Fairbanks, Alaska, to those typical of Cave Creek, Arizona.…

  18. Transportation: Topic Paper E.

    ERIC Educational Resources Information Center

    National Council on the Handicapped, Washington, DC.

    As one of a series of topic papers assessing federal laws and programs affecting persons with disabilities, this paper reviews the issue of transportation services. In the area of urban mass transit, four relevant pieces of legislation and public transportation accessibility regulations are cited, and cost issues are explored. Paratransit systems,…

  19. Transportation: Topic Paper E.

    ERIC Educational Resources Information Center

    National Council on the Handicapped, Washington, DC.

    As one of a series of topic papers assessing federal laws and programs affecting persons with disabilities, this paper reviews the issue of transportation services. In the area of urban mass transit, four relevant pieces of legislation and public transportation accessibility regulations are cited, and cost issues are explored. Paratransit systems,…

  20. Trajectory structures and transport

    SciTech Connect

    Vlad, Madalina; Spineanu, Florin

    2004-11-01

    The special problem of transport in two-dimensional divergence-free stochastic velocity fields is studied by developing a statistical approach, the nested subensemble method. The nonlinear process of trapping determined by such fields generates trajectory structures whose statistical characteristics are determined. These structures strongly influence the transport.

  1. Morphogen transport in epithelia

    NASA Astrophysics Data System (ADS)

    Bollenbach, T.; Kruse, K.; Pantazis, P.; González-Gaitán, M.; Jülicher, F.

    2007-01-01

    We present a general theoretical framework to discuss mechanisms of morphogen transport and gradient formation in a cell layer. Trafficking events on the cellular scale lead to transport on larger scales. We discuss in particular the case of transcytosis where morphogens undergo repeated rounds of internalization into cells and recycling. Based on a description on the cellular scale, we derive effective nonlinear transport equations in one and two dimensions which are valid on larger scales. We derive analytic expressions for the concentration dependence of the effective diffusion coefficient and the effective degradation rate. We discuss the effects of a directional bias on morphogen transport and those of the coupling of the morphogen and receptor kinetics. Furthermore, we discuss general properties of cellular transport processes such as the robustness of gradients and relate our results to recent experiments on the morphogen Decapentaplegic (Dpp) that acts in the wing disk of the fruit fly Drosophila.

  2. Undulator Transportation Test Results

    SciTech Connect

    Wolf, Zachary; Horton, Nick; Kharakh, David; Levashov, Yurii; Nuhn, Heinz-Dieter; Poling, Ben; Reese, Ed; /SLAC

    2010-11-17

    A test was performed to determine whether transporting and handling the undulators makes any changes to their properties. This note documents the test. No significant changes to the test undulator were observed. After the LCLS undulators are tuned and fiducialized in the Magnetic Measurement Facility (MMF), they must be transported to storage buildings and transported to the tunnel. It has been established that the undulators are sensitive to temperature. We wish to know whether the undulators are also sensitive to the vibrations and shocks of transportation. To study this issue, we performed a test in which an undulator was measured in the MMF, transported to the tunnel, brought back to the MMF, and re-measured. This note documents the test and the results.

  3. Organic Anion Transporting Polypeptides

    PubMed Central

    Stieger, Bruno; Hagenbuch, Bruno

    2013-01-01

    Organic anion transporting polypeptides or OATPs are central transporters in the disposition of drugs and other xenobiotics. In addition, they mediate transport of a wide variety of endogenous substrates. The critical role of OATPs in drug disposition has spurred research both in academia and in the pharmaceutical industry. Translational aspects with clinical questions are the focus in academia, while the pharmaceutical industry tries to define and understand the role these transporters play in pharmacotherapy. The present overview summarizes our knowledge on the interaction of food constituents with OATPs, and on the OATP transport mechanisms. Further, it gives an update on the available information on the structure-function relationship of the OATPs, and finally, covers the transcriptional and posttranscriptional regulation of OATPs. PMID:24745984

  4. Modeling Transport Layer Protocols

    NASA Astrophysics Data System (ADS)

    Sasnauskas, Raimondas; Weingaertner, Elias

    In a layered communication architecture, transport layer protocols handle the data exchange between processes on different hosts over potentially lossy communication channels. Typically, transport layer protocols are either connection-oriented or are based on the transmission of individual datagrams. Well known transport protocols are the connection-oriented Transmission Control Protocol (TCP) [372] and the User Datagram Protocol (UDP) [370] as well as the Stream Control Transmission Protocol (SCTP) [340] and DCCP, the Datagram Congestion Control Protocol [259]. In this chapter, we focus on the modeling process of the transport layer. While we mostly use TCP and UDP as a base of comparison from this point, we emphasize that the methodologies discussed further on are conferrable to virtually any transport layer in any layered communication architecture.

  5. Design and function of a structured illumination system for use in an AO microscope

    NASA Astrophysics Data System (ADS)

    Kissel, Matthew

    The design and function of a Structured Illumination system for use as part of an Adaptive Optics Structured Illumination Microscope (AOSIM) is presented. After successful implementation of AO in a standard widefield microscope, our lab wanted to apply the technology to a more advanced imaging modality that has a lot to gain from the AO system. SIM allows us to reconstruct an image with resolution beyond the Rayleigh limit of the optics, called a super-resolution image, by aliasing high spatial frequencies, outside the limit of the optics, to lower frequencies within the system pass band. The aliasing is accomplished by spatially modulating the illumination at a frequency near the cutoff frequency of the system. These aliased frequencies are superimposed on the lower spatial frequencies of the object in our image. Using multiple images and an inverse algorithm, we separate the aliased and normal frequencies, restore them to their original frequency positions, and recreate the original spectrum of the object. This allows us to recreate a super-resolution image of the object. We show that our SIM system creates images that are a higher resolution than a standard wide-field microscope.

  6. VizieR Online Data Catalog: Robo-AO observed cool subdwarf companions (Ziegler+, 2015)

    NASA Astrophysics Data System (ADS)

    Ziegler, C.; Law, N. M.; Baranec, C.; Riddle, R. L.; Fuchs, J. T.

    2017-09-01

    We selected targets from the 564 spectral type F- through M-subdwarf candidates studied by Marshall (2007, J/AJ/134/778). These targets were selected from the New Luyten Two-Tenths catalog (NLTT; Luyten, 1979nlcs.book.....L; Luyten & Hughes 1980, Proper-Motion Survey with the Forty-Eight Inch Schmidt Telescope LV First Supplement to the NLTT Catalogue (Minneapolis, MN: Univ. Minnesota Press)) of high proper motion stars (>0.18 arcsec/yr) using a reduced proper motion diagram (RPM). Of the 552 subdwarfs confirmed by Marshall, a randomly selected sample of 348 G-, K-, and M-subdwarfs were observed by Robo-AO when available between other high priority surveys. We obtained high-angular-resolution images of the 348 subdwarfs during 32 separate nights of observations between 2012 September 3 and 2013 August 21 (UT). The observations were performed using the Robo-AO laser adaptive optics system (Riddle et al. 2012SPIE.8447E..2OR; Baranec et al. 2013, J. Visualized Exp. 72 e50021; 2014ApJ...790L...8B) mounted on the Palomar 60 inch telescope. (1 data file).

  7. Facility class Rayleigh beacon AO system for the 4.2m William Herschel telescope

    NASA Astrophysics Data System (ADS)

    Rutten, René G.; Clark, Paul; Myers, Richard M.; Wilson, Richard W.; Bingham, Richard G.; Emsellem, Eric; Gregory, Thomas; Humphreys, Ronald A.; Knapen, Johan; Moretto, Gilberto; Morris, Simon L.; Talbot, Gordon

    2003-02-01

    A rationale is presented for the use of a relatively low-altitude (15km) Rayleigh Laser Guide Star to provide partial adaptive optics correction across a large fraction of the sky on the 4.2m William Herschel Telescope. The scientific motivation in relation to the available instrumentation suite is discussed and supported by model performance calculations, based on observed atmospheric turbulence distributions at the site. The proposed implementation takes the form of a laser system, beam diagnostics, tip-tilt mirror and beacon launch telescope, together with a range-gated wavefront sensor and processing system. It is designed to operate in conjunction with the telescope"s existing facility-class natural guide star AO system, NAOMI. Aspects of the proposed implementation are described as well as the technical features related to the system model and the error budget. In a separate paper the NAOMI AO system itself is presented. Other papers describe a demonstrator system and preliminary Rayleigh beacon wavefront sensing measurements at the site.

  8. Risk Factors Associated with Campylobacter jejuni Infections in Curaçao, Netherlands Antilles

    PubMed Central

    Endtz, Hubert P.; van West, Hanneke; Godschalk, Peggy C. R.; de Haan, Lidewij; Halabi, Yaskara; van den Braak, Nicole; Kesztyüs, Barbara I.; Leyde, Ewald; Ott, Alewijn; Verkooyen, Roel; Price, Lawrence J.; Woodward, David L.; Rodgers, Frank G.; Ang, C. Wim; van Koningsveld, Rinske; van Belkum, Alex; Gerstenbluth, Izzy

    2003-01-01

    A steady increase in the incidence of Guillain-Barré syndrome (GBS) with a seasonal preponderance, almost exclusively related to Campylobacter jejuni, and a rise in the incidence of laboratory-confirmed Campylobacter enteritis have been reported from Curaçao, Netherlands Antilles. We therefore investigated possible risk factors associated with diarrhea due to epidemic C. jejuni. Typing by pulsed-field gel electrophoresis identified four epidemic clones which accounted for almost 60% of the infections. One hundred six cases were included in a case-control study. Infections with epidemic clones were more frequently observed in specific districts in Willemstad, the capital of Curaçao. One of these clones caused infections during the rainy season only and was associated with the presence of a deep well around the house. Two out of three GBS-related C. jejuni isolates belonged to an epidemic clone. The observations presented point toward water as a possible source of Campylobacter infections. PMID:14662945

  9. LDEF (Prelaunch), AO076 : Cascade Variable-Conductance Heat Pipe, Tray F09

    NASA Technical Reports Server (NTRS)

    1983-01-01

    LDEF (Prelaunch), AO076 : Cascade Variable-Conductance Heat Pipe, Tray F09 EL-1994-00302 LDEF (Prelaunch), AO076 : Cascade Variable-Conductance Heat Pipe, Tray F09 The prelaunch photograph was taken in SAEF II at KSC prior to installation of the Cascade Variable Conductance Heat Pipe Experiment (CVCHPE) on the LDEF. The Cascade Variable Conductance Heat Pipe Experiment (CVCHPE) occupies a 6 inch deep LDEF peripheral experiment tray and consist of two series connected variable conductance heatpipes, a black chrome solar collector panel and a silvered TEFLON® radiator panel, a power source to support six thermistor-type temperature monitoring sensors and actuations of two valves. Fiberglass standoffs and internal insulation blankets thermally isolated the experiment from the experiment tray and the LDEF interior. The outside of the CVCHPE, except the collector and radiator panels, was covered with an aluminumized Kapton multilayer insulation (MLI) blanket with an outer layer of 0.076 mm thick Kapton. The two patches of thin film materials, part of Experiment S1001 by NASA GSFC, were attached to the cover of the external thermal blanket with Kapton tape. The experiment was assembled and mounted in the experiment tray with non-magnetic stainless steel fasteners.

  10. AO WFS detector developments at ESO to prepare for the E-ELT

    NASA Astrophysics Data System (ADS)

    Downing, Mark; Casali, Mark; Finger, Gert; Lewis, Steffan; Marchetti, Enrico; Mehrgan, Leander; Ramsay, Suzanne; Reyes, Javier

    2016-07-01

    ESO has a very active on-going AO WFS detector development program to not only meet the needs of the current crop of instruments for the VLT, but also has been actively involved in gathering requirements, planning, and developing detectors and controllers/cameras for the instruments in design and being proposed for the E-ELT. This paper provides an overall summary of the AO WFS Detector requirements of the E-ELT instruments currently in design and telescope focal units. This is followed by a description of the many interesting detector, controller, and camera developments underway at ESO to meet these needs; a) the rationale behind and plan to upgrade the 240x240 pixels, 2000fps, "zero noise", L3Vision CCD220 sensor based AONGC camera; b) status of the LGSD/NGSD High QE, 3e- RoN, fast 700fps, 1760x1680 pixels, Visible CMOS Imager and camera development; c) status of and development plans for the Selex SAPHIRA NIR eAPD and controller. Most of the instruments and detector/camera developments are described in more detail in other papers at this conference.

  11. Closed-loop focal plane wavefront control with the SCExAO instrument

    NASA Astrophysics Data System (ADS)

    Martinache, Frantz; Jovanovic, Nemanja; Guyon, Olivier

    2016-09-01

    Aims: This article describes the implementation of a focal plane based wavefront control loop on the high-contrast imaging instrument SCExAO (Subaru Coronagraphic Extreme Adaptive Optics). The sensor relies on the Fourier analysis of conventional focal-plane images acquired after an asymmetric mask is introduced in the pupil of the instrument. Methods: This absolute sensor is used here in a closed-loop to compensate for the non-common path errors that normally affects any imaging system relying on an upstream adaptive optics system.This specific implementation was used to control low-order modes corresponding to eight zernike modes (from focus to spherical). Results: This loop was successfully run on-sky at the Subaru Telescope and is used to offset the SCExAO deformable mirror shape used as a zero-point by the high-order wavefront sensor. The paper details the range of errors this wavefront-sensing approach can operate within and explores the impact of saturation of the data and how it can be bypassed, at a cost in performance. Conclusions: Beyond this application, because of its low hardware impact, the asymmetric pupil Fourier wavefront sensor (APF-WFS) can easily be ported in a wide variety of wavefront sensing contexts, for ground- as well space-borne telescopes, and for telescope pupils that can be continuous, segmented or even sparse. The technique is powerful because it measures the wavefront where it really matters, at the level of the science detector.

  12. Demonstration of the suitability of GPUs for AO real-time control at ELT scales

    NASA Astrophysics Data System (ADS)

    Bitenc, Urban; Basden, Alastair G.; Dipper, Nigel A.; Myers, Richard M.

    2016-07-01

    We have implemented the full AO data-processing pipeline on Graphics Processing Units (GPUs), within the framework of Durham AO Real-time Controller (DARC). The wavefront sensor images are copied from the CPU memory to the GPU memory. The GPU processes the data and the DM commands are copied back to the CPU. For a SCAO system of 80x80 subapertures, the rate achieved on a single GPU is about 700 frames per second (fps). This increases to 1100 fps (1565 fps) if we use two (four) GPUs. Jitter exhibits a distribution with the root-mean-square value of 20 μs-30 μs and a negligible number of outliers. The increase in latency due to the pixel data copying from the CPU to the GPU has been reduced to the minimum by copying the data in parallel to processing them. An alternative solution in which the data would be moved from the camera directly to the GPU, without CPU involvement, could be about 10%-20% faster. We have also implemented the correlation centroiding algorithm, which - when used - reduces the frame rate by about a factor of 2-3.

  13. LDEF (Postflight), AO187-01 : The Chemistry of Micrometeoroids, Tray A03

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Postflight), AO187-01 : The Chemistry of Micrometeoroids, Tray A03 EL-1994-00266 LDEF (Postflight), AO187-01 : The Chemistry of Micrometeoroids, Tray A03 The experiment is shown in the postflight configuration before closing the canisters with ground support equipment that bypassed the experiments onboard electronics circuitry. Three full panels and approximately 3/4th of the other panel are covered with gold foil (>99.99 percent pure). The remaining area on the fourth panel is covered with strips of other detector materials: zirconium, beryllium, titanium, platium, aluminum, carbon, Kapton, polyethylene and TEFLON®. A brown stain is visible on the experiment tray flanges, however, most of the stains observed in the flight photograph are obscured by reflected light. All materials remain intact with no visual evidence of damage to the experiment. The reflection of a video camera on a tripod and light sources can be seen on the gold foil covered panels. The experiment canisters are shown after being closed by using the experiments ground support equipment. The stain buildup can be clearly seen at the vertical center of the right tray flange. The clean area was located under the experiment tray clamp block and was not exposed to the staining medium. The stain also coats other areas that were exposed during the mission but are not as noticeable. The experiment hardware seems to be intact and have no damage.

  14. LDEF (Flight), AO187-01 : The Chemistry of Micrometeoroids, Tray A03

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Flight), AO187-01 : The Chemistry of Micrometeoroids, Tray A03 EL-1994-00680 LDEF (Flight), AO187-01 : The Chemistry of Micrometeoroids, Tray A03 The flight photograph was taken with the LDEF on the Orbiter's RMS arm prior to berthing the spacecraft in the cargo bay. The canisters are in their open condition (they were expected to open about two (2) weeks after launch and close about eleven (11) months into the mission) with three (3) full panels and 3/4th of the fourth panel covered with a highly reflective gold foil (>99.99 percent pure).The remaining area is covered with strips of other detector materials: zirconium, beryllium, titanium, platium, aluminum, carbon, Kapton, polyethylene and TEFLON®. The exposed fasteners are non-magnetic stainless steel. All of the exposed materials seem to be secure and no damage is evident. The contamination stain that has changed the white paint dot on the tray clamp blocks to brown also coats the tray flanges and the aluminum canister hardware. The end support beam scuff plate in the photograph was a bright yellow prior to launch but is a much darker, mustard yellow after the space exposure.

  15. Instrument control software development process for the multi-star AO system ARGOS

    NASA Astrophysics Data System (ADS)

    Kulas, M.; Barl, L.; Borelli, J. L.; Gässler, W.; Rabien, S.

    2012-09-01

    The ARGOS project (Advanced Rayleigh guided Ground layer adaptive Optics System) will upgrade the Large Binocular Telescope (LBT) with an AO System consisting of six Rayleigh laser guide stars. This adaptive optics system integrates several control loops and many different components like lasers, calibration swing arms and slope computers that are dispersed throughout the telescope. The purpose of the instrument control software (ICS) is running this AO system and providing convenient client interfaces to the instruments and the control loops. The challenges for the ARGOS ICS are the development of a distributed and safety-critical software system with no defects in a short time, the creation of huge and complex software programs with a maintainable code base, the delivery of software components with the desired functionality and the support of geographically distributed project partners. To tackle these difficult tasks, the ARGOS software engineers reuse existing software like the novel middleware from LINC-NIRVANA, an instrument for the LBT, provide many tests at different functional levels like unit tests and regression tests, agree about code and architecture style and deliver software incrementally while closely collaborating with the project partners. Many ARGOS ICS components are already successfully in use in the laboratories for testing ARGOS control loops.

  16. A decadal survey of AO wavefront sensing detector developments in Europe

    NASA Astrophysics Data System (ADS)

    Feautrier, Philippe

    2011-09-01

    The success of the next generation of instruments for 8 to 40-m class telescopes will depend on the ability of Adaptive Optics (AO) systems to provide excellent image quality and stability. This will be achieved by increasing the sampling, wavelength range and correction quality of the wave front error in both spatial and time domains. The modern generation of AO wavefront sensor detectors started in the late nineties with the development of the CCD50 detector by e2v under ESO contract for the ESO NAOS AO system. With a 128x128 pixels format, this 8 outputs CCD runs at a 500 Hz frame rate with a readout noise of 7e-. A major breakthrough has been achieved with the recent development of the CCD220, also by e2v technologies. This 240x240 pixels 8 outputs EMCCD (CCD with internal multiplication), also developed by e2v, has been jointly funded by ESO and Europe under the FP6 programme. The CCD220 detector and the OCAM2 camera are now the most sensitive system in the world for advanced adaptive optics systems, offering an astonishing <0.2 e readout noise at a frame rate of 1500 Hz with negligible dark current. Extremely easy to operate, OCAM2 only needs a 24 V power supply and a modest water cooling circuit. This system is extensively described elsewhere in this conference (see Gach J-L. et al). An upgrade of OCAM2 is foreseen to boost its frame rate to 2500 Hz, opening the window of XAO wavefront sensing for the ELT. Since this major success, new developments started in Europe. One is fully dedicated to Laser Guide Star AO for the ELT. The spot elongation from a LGS SH wavefront sensor induces an increase of the pixel format. Two detectors are currently developed by e2v. The NGSD will be a 672x672 pixels CMOS detector with a readout noise of 4e (goal 1e) at 700 Hz frame rate. The LGSD is a scaling of the NGSD with 1680x1680 pixels and 3 e readout noise (goal 1e) at 700 Hz frame rate. New technologies will be developed for that purpose: new CMOS pixel architecture, CMOS

  17. Bile acid transporters

    PubMed Central

    Dawson, Paul A.; Lan, Tian; Rao, Anuradha

    2009-01-01

    In liver and intestine, transporters play a critical role in maintaining the enterohepatic circulation and bile acid homeostasis. Over the past two decades, there has been significant progress toward identifying the individual membrane transporters and unraveling their complex regulation. In the liver, bile acids are efficiently transported across the sinusoidal membrane by the Na+ taurocholate cotransporting polypeptide with assistance by members of the organic anion transporting polypeptide family. The bile acids are then secreted in an ATP-dependent fashion across the canalicular membrane by the bile salt export pump. Following their movement with bile into the lumen of the small intestine, bile acids are almost quantitatively reclaimed in the ileum by the apical sodium-dependent bile acid transporter. The bile acids are shuttled across the enterocyte to the basolateral membrane and effluxed into the portal circulation by the recently indentified heteromeric organic solute transporter, OSTα-OSTβ. In addition to the hepatocyte and enterocyte, subgroups of these bile acid transporters are expressed by the biliary, renal, and colonic epithelium where they contribute to maintaining bile acid homeostasis and play important cytoprotective roles. This article will review our current understanding of the physiological role and regulation of these important carriers. PMID:19498215

  18. Thyroid hormone transporter defects.

    PubMed

    Grüters, Annette

    2007-01-01

    In in vitro experiments, active transport of thyroid hormones had been repeatedly demonstrated. The membrane transporters for thyroid hormones which have been identified include the organic anion transporting polypeptide, heterodimeric amino acid transporters and the monocarboxylate transporters (MCT) which are the focus of this chapter. The gene encoding MCT8 which was identified as a specific thyroid hormone transporter is located on chromosome Xq13.2. The expression pattern of MCT8 indicates that MCT8 plays an important role in the development of the central nervous system by transporting thyroid hormone into neurons as its main target cells. Mutational analysis of the MCT8 gene revealed mutations or deletions in the MCT8 gene in unrelated male patients with severe psychomotor retardation and biochemical findings consistent with thyroid hormone resistance. Indeed, thyroid function tests in patients with MCT8 mutations demonstrated marked elevations of serum T3 (in the thyrotoxic range), a significant decrease in serum T4 or fT4 and normal to elevated TSH levels.

  19. Bile acid transporters.

    PubMed

    Dawson, Paul A; Lan, Tian; Rao, Anuradha

    2009-12-01

    In liver and intestine, transporters play a critical role in maintaining the enterohepatic circulation and bile acid homeostasis. Over the past two decades, there has been significant progress toward identifying the individual membrane transporters and unraveling their complex regulation. In the liver, bile acids are efficiently transported across the sinusoidal membrane by the Na(+) taurocholate cotransporting polypeptide with assistance by members of the organic anion transporting polypeptide family. The bile acids are then secreted in an ATP-dependent fashion across the canalicular membrane by the bile salt export pump. Following their movement with bile into the lumen of the small intestine, bile acids are almost quantitatively reclaimed in the ileum by the apical sodium-dependent bile acid transporter. The bile acids are shuttled across the enterocyte to the basolateral membrane and effluxed into the portal circulation by the recently indentified heteromeric organic solute transporter, OSTalpha-OSTbeta. In addition to the hepatocyte and enterocyte, subgroups of these bile acid transporters are expressed by the biliary, renal, and colonic epithelium where they contribute to maintaining bile acid homeostasis and play important cytoprotective roles. This article will review our current understanding of the physiological role and regulation of these important carriers.

  20. Transportation energy data book

    NASA Astrophysics Data System (ADS)

    Davis, S. C.; Hu, P. S.

    1991-01-01

    The Transportation Energy Data Book: Edition 11 is a statistical compendium prepared and published by Oak Ridge National Laboratory (ORNL) under contract with the Office of Transportation Technologies in the Department of Energy (DOE). Designed for use as a desk-top reference, the data book represents an assembly and display of statistics and information that characterize transportation activity, and presents data on other factors that influence transportation energy use. The purpose of this document is to present relevant statistical data in the form of tables and graphs. Each of the major transportation modes - highway, air, water, rail, pipeline - is treated in separate chapters or sections. Chapter 1 compares U.S. transportation data with data from seven other countries. Aggregate energy use and energy supply data for all modes are presented in Chapter 2. The highway mode, which accounts for over three-fourths of total transportation energy consumption, is dealt with in Chapter 3. Topics in this chapter include automobiles, trucks, buses, fleet automobiles, Federal standards, fuel economies, and household data. Chapter 4 is a new addition to the data book series, containing information on alternative fuels and alternatively-fueled vehicles. The last chapter, Chapter 5, covers each of the nonhighway modes: air, water, pipeline, and rail, respectively.

  1. SLC4A Transporters

    PubMed Central

    Choi, Inyeong

    2016-01-01

    SLC4A gene family proteins include bicarbonate transporters that move HCO3− across the plasma membrane and regulate intracellular pH and transepithelial movement of acid–base equivalents. These transporters are Cl/HCO3 exchangers, electrogenic Na/HCO3 cotransporters, electroneutral Na/HCO3 cotransporters, and Na+-driven Cl/HCO3 exchanger. Studies of the bicarbonate transporters in vitro and in vivo have demonstrated their physiological importance for acid–base homeostasis at the cellular and systemic levels. Recent advances in structure/function analysis have also provided valuable information on domains or motifs critical for regulation, ion translocation, and protein topology. This chapter focuses on the molecular mechanisms of ion transport along with associated structural aspects from mutagenesis of particular residues and from chimeric constructs. Structure/function studies have helped to understand the mechanism by which ion substrates are moved via the transporters. This chapter also describes some insights into the structure of SLC4A1 (AE1) and SLC4A4 (NBCe1) transporters. Finally, as some SLC4A transporters exist in concert with other proteins in the cells, the structural features associated with protein–protein interactions are briefly discussed. PMID:23177984

  2. Transport properties of ions

    NASA Technical Reports Server (NTRS)

    Biolsi, Louis; Biolsi, David

    1987-01-01

    The strong long-range interactions between (among) charged species require the inclusion of higher order contributions to the transport properties (viscosity, thermal conductivity, diffusion) of ionized gases than are required for neutral gases. These higher order contributions have been rewritten so that they are given in terms of universal functions which can be tabulated. Tables which provide for the rapid calculation of some higher order contributions to the transport properties of both ions and electrons are given. Some results which are useful for calculating the higher order contributions to the transport properties of mixtures of ions are also given. These results are applied to the ionic species in air at high temperatures.

  3. Quantum Transport in Semiconductors

    DTIC Science & Technology

    1991-10-01

    SRS i 91 4. TITLE AND SUBTITLE Quantum Transport in Semiconductors 5. FUNDING NUMBER söMtos-rizk-ooss 6. AUTHOR(S) D. K. Ferry ©fte ELECTE...OF ABSTRACT UL NSN 7540-01-280-5500 O 1 9 Standard Form 298 (Rev. 2-89) Presented by ANSI Std «9-18 298-102 Final Report Quantum Transport in... Quantum Transport in Semiconductor Devices This final report describes a program of research investigating quantum effects which become important in

  4. Fuels for transportation.

    PubMed

    Fredholm, Bertil B; Nordén, Bengt

    2010-01-01

    There is a need to reduce the amount of fossil energy used for transport, both because of the easily available fossil fuel is becoming sparser and because of climate concerns. In this article, the concept of "peak oil" is briefly presented. Second, a practical approach to reduction of fossil fuel use for transport elaborated by two British commissions is presented. A key feature is the introduction of electric cars. This raises the third issue covered in this article: namely, how battery technology is going to meet the increasing needs posed by the transport sector.

  5. The MeJA-inducible copper amine oxidase AtAO1 is expressed in xylem tissue and guard cells.

    PubMed

    Ghuge, Sandip A; Carucci, Andrea; Rodrigues-Pousada, Renato A; Tisi, Alessandra; Franchi, Stefano; Tavladoraki, Paraskevi; Angelini, Riccardo; Cona, Alessandra

    2015-01-01

    Copper amine oxidases oxidize the polyamine putrescine to 4-aminobutanal with the production of the plant signal molecule hydrogen peroxide (H2O2) and ammonia. The Arabidopsis (Arabidopsis thaliana) gene At4g14940 (AtAO1, previously referred to as ATAO1) encodes an apoplastic copper amine oxidase expressed in lateral root cap cells and developing xylem, especially in root protoxylem and metaxylem precursors. In our recent study, we demonstrated that AtAO1 expression is strongly induced in the root vascular tissues by the wound-signal hormone methyl jasmonate (MeJA). Furthermore, we also demonstrated that the H2O2 derived by the AtAO1-driven oxidation of putrescine, mediates the MeJA-induced early protoxylem differentiation in Arabidopsis roots. H2O2 may contribute to protoxylem differentiation by signaling developmental cell death and by acting as co-substrate in peroxidase-mediated cell wall stiffening and lignin polymerization. Here, by the means of AtAO1 promoter::green fluorescent protein-β-glucuronidase (AtAO1::GFP-GUS) fusion analysis, we show that a strong AtAO1 gene expression occurs also in guard cells of leaves and flowers. The high expression levels of AtAO1 in tissues or cell types regulating water supply and water loss may suggest a role of the encoded protein in water balance homeostasis, by modulating coordinated adjustments in anatomical and functional features of xylem tissue and guard cells during acclimation to adverse environmental conditions.

  6. Evaluating the Reliability and Reproducibility of the AO and Lauge-Hansen Classification Systems for Ankle Injuries.

    PubMed

    Yin, Meng-Chen; Yuan, Xue-Fei; Ma, Jun-Ming; Xia, Ye; Wang, Tao; Xu, Xiao-Li; Yan, Yin-Jie; Xu, Jin-Hai; Ye, Jie; Tong, Zheng-Yi; Feng, Yan-Qi; Wang, Hong-Bo; Wu, Xue-Qun; Mo, Wen

    2015-07-01

    Ankle injuries are responsible for more than 5 million emergency department visits each year. The AO and Lauge-Hansen classification systems are widely used in the clinical diagnosis of ankle injuries. This study aimed to analyze the intraobserver reliability and interobserver reproducibility of the AO and Lauge-Hansen classification systems. In addition, the authors explored the differences among physicians' classification responses and evaluated the clinical value for diagnosis. Fifty-six patients with an ankle injury with complete clinical and radiologic data were enrolled. The definition of injury type, the index score typing methods, and the specific study criteria were explained in detail. Five observers, who were orthopedic surgeons, determined the classifications according to both the AO and Lauge-Hansen systems. The classification was repeated 1 month later. Cronbach's alpha and Cohen's kappa test were used to determine interobserver reliability and intraobserver reproducibility. The physicians conducted 560 classifications (56 cases × 5 physicians × 2 times per patient). Average inter- and intraobserver kappa values for the AO system were 0.708 and 0.608, respectively. Average inter- and intraobserver kappa values for the Lauge-Hansen system were 0.402 and 0.398, respectively. Cronbach's alpha coefficient was 96.7% for the AO system and 76.0% for the Lauge-Hansen system. The Lauge-Hansen classification system is a comprehensive yet cumbersome system. Comparatively, the AO classification system is easier to understand. This study shows that the AO classification system has more reliability and reproducibility, and thus has more value in clinical practice, than the Lauge-Hansen classification system.

  7. EBS Radionuclide Transport Abstraction

    SciTech Connect

    J.D. Schreiber

    2005-08-25

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers

  8. Transportation Network Topologies

    NASA Technical Reports Server (NTRS)

    Alexandrov, Natalia (Editor)

    2004-01-01

    The existing U.S. hub-and-spoke air transportation system is reaching saturation. Major aspects of the current system, such as capacity, safety, mobility, customer satisfaction, security, communications, and ecological effects, require improvements. The changing dynamics - increased presence of general aviation, unmanned autonomous vehicles, military aircraft in civil airspace as part of homeland defense - contributes to growing complexity of airspace. The system has proven remarkably resistant to change. NASA Langley Research Center and the National Institute of Aerospace conducted a workshop on Transportation Network Topologies on 9-10 December 2003 in Williamsburg, Virginia. The workshop aimed to examine the feasibility of traditional methods for complex system analysis and design as well as potential novel alternatives in application to transportation systems, identify state-of-the-art models and methods, conduct gap analysis, and thus to lay a foundation for establishing a focused research program in complex systems applied to air transportation.

  9. Crew Transportation Operations Standards

    NASA Technical Reports Server (NTRS)

    Mango, Edward J.; Pearson, Don J. (Compiler)

    2013-01-01

    The Crew Transportation Operations Standards contains descriptions of ground and flight operations processes and specifications and the criteria which will be used to evaluate the acceptability of Commercial Providers' proposed processes and specifications.

  10. Latest in Campus Transportation

    ERIC Educational Resources Information Center

    Molloy, Larry

    1974-01-01

    Innovations in handling bicycles, autos, and buses are appearing on campuses across the country. Computer-driven shuttle cars and monorails are on the way. Provides information sources for more data about ongoing, innovative campus transportation programs. (Author)

  11. Nebraska Department of Transportation

    EPA Pesticide Factsheets

    The EPA is providing notice of a proposed Administrative Penalty Assessment against the Nebraska Department of Transportation, a state agency located at 1500 Highway 2, Lincoln, NE 68509, for alleged violations of its municipal separate stormwater sewer sy

  12. Commercial Crew Transportation Capability

    NASA Image and Video Library

    2014-09-16

    Kathy Lueders, program manager of NASA's Commercial Crew Program, speaks during a news conference where it was announced that Boeing and SpaceX have been selected to transport U.S. crews to and from the International Space Station using the Boeing CST-100 and the SpaceX Crew Dragon spacecraft, at NASA’s Kennedy Space Center in Cape Canaveral, Fla. on Tuesday, Sept. 16, 2014. These Commercial Crew Transportation Capability (CCtCap) contracts are designed to complete the NASA certification for a human space transportation system capable of carrying people into orbit. Once certification is complete, NASA plans to use these systems to transport astronauts to the space station and return them safely to Earth. Photo Credit: (NASA/Bill Ingalls)

  13. Commercial Crew Transportation Capability

    NASA Image and Video Library

    2014-09-16

    Former astronaut Bob Cabana, director of NASA's Kennedy Space Center in Florida, speaks during a news conference where it was announced that Boeing and SpaceX have been selected to transport U.S. crews to and from the International Space Station using the Boeing CST-100 and the SpaceX Crew Dragon spacecraft, at NASA’s Kennedy Space Center in Cape Canaveral, Fla. on Tuesday, Sept. 16, 2014. These Commercial Crew Transportation Capability (CCtCap) contracts are designed to complete the NASA certification for a human space transportation system capable of carrying people into orbit. Once certification is complete, NASA plans to use these systems to transport astronauts to the space station and return them safely to Earth. Photo Credit: (NASA/Bill Ingalls)

  14. Commercial Crew Transportation Capability

    NASA Image and Video Library

    2014-09-16

    Kathy Lueders, program manager of NASA's Commercial Crew Program, speaks, as Former astronaut Bob Cabana, director of NASA's Kennedy Space Center in Florida, left, and Astronaut Mike Fincke, a former commander of the International Space Station look on during a news conference where it was announced that Boeing and SpaceX have been selected to transport U.S. crews to and from the International Space Station using the Boeing CST-100 and the SpaceX Crew Dragon spacecraft, at NASA’s Kennedy Space Center in Cape Canaveral, Fla. on Tuesday, Sept. 16, 2014. These Commercial Crew Transportation Capability (CCtCap) contracts are designed to complete the NASA certification for a human space transportation system capable of carrying people into orbit. Once certification is complete, NASA plans to use these systems to transport astronauts to the space station and return them safely to Earth. Photo Credit: (NASA/Bill Ingalls)

  15. Commercial Crew Transportation Capability

    NASA Image and Video Library

    2014-09-16

    Astronaut Mike Fincke, a former commander of the International Space Station, speaks during a news conference where it was announced that Boeing and SpaceX have been selected to transport U.S. crews to and from the International Space Station using the Boeing CST-100 and the SpaceX Crew Dragon spacecraft, at NASA’s Kennedy Space Center in Cape Canaveral, Fla. on Tuesday, Sept. 16, 2014. These Commercial Crew Transportation Capability (CCtCap) contracts are designed to complete the NASA certification for a human space transportation system capable of carrying people into orbit. Once certification is complete, NASA plans to use these systems to transport astronauts to the space station and return them safely to Earth. Photo Credit: (NASA/Bill Ingalls)

  16. Commercial Crew Transportation Capability

    NASA Image and Video Library

    2014-09-16

    NASA Administrator Charles Bolden, left, announces the agency’s selection of Boeing and SpaceX to transport U.S. crews to and from the International Space Station using the Boeing CST-100 and the SpaceX Crew Dragon spacecraft as Former astronaut Bob Cabana, director of NASA's Kennedy Space Center in Florida looks on at NASA’s Kennedy Space Center in Cape Canaveral, Fla. on Tuesday, Sept. 16, 2014. These Commercial Crew Transportation Capability (CCtCap) contracts are designed to complete the NASA certification for a human space transportation system capable of carrying people into orbit. Once certification is complete, NASA plans to use these systems to transport astronauts to the space station and return them safely to Earth. Photo Credit: (NASA/Bill Ingalls)

  17. Commercial Crew Transportation Capability

    NASA Image and Video Library

    2014-09-16

    From left, NASA Public Affairs Officer Stephanie Schierholz, NASA Administrator Charles Bolden, Former astronaut Bob Cabana, director of NASA's Kennedy Space Center in Florida, Kathy Lueders, program manager of NASA's Commercial Crew Program, and Astronaut Mike Fincke, a former commander of the International Space Station, are seen during a news conference where it was announced that Boeing and SpaceX have been selected to transport U.S. crews to and from the International Space Station using the Boeing CST-100 and the SpaceX Crew Dragon spacecraft, at NASA’s Kennedy Space Center in Cape Canaveral, Fla. on Tuesday, Sept. 16, 2014. These Commercial Crew Transportation Capability (CCtCap) contracts are designed to complete the NASA certification for a human space transportation system capable of carrying people into orbit. Once certification is complete, NASA plans to use these systems to transport astronauts to the space station and return them safely to Earth. Photo Credit: (NASA/Bill Ingalls)

  18. Animal transportation networks

    PubMed Central

    Perna, Andrea; Latty, Tanya

    2014-01-01

    Many group-living animals construct transportation networks of trails, galleries and burrows by modifying the environment to facilitate faster, safer or more efficient movement. Animal transportation networks can have direct influences on the fitness of individuals, whereas the shape and structure of transportation networks can influence community dynamics by facilitating contacts between different individuals and species. In this review, we discuss three key areas in the study of animal transportation networks: the topological properties of networks, network morphogenesis and growth, and the behaviour of network users. We present a brief primer on elements of network theory, and then discuss the different ways in which animal groups deal with the fundamental trade-off between the competing network properties of travel efficiency, robustness and infrastructure cost. We consider how the behaviour of network users can impact network efficiency, and call for studies that integrate both network topology and user behaviour. We finish with a prospectus for future research. PMID:25165598

  19. Air transportation energy efficiency

    NASA Technical Reports Server (NTRS)

    Williams, L. J.

    1977-01-01

    The energy efficiency of air transportation, results of the recently completed RECAT studies on improvement alternatives, and the NASA Aircraft Energy Efficiency Research Program to develop the technology for significant improvements in future aircraft were reviewed.

  20. Accident resistant transport container

    DOEpatents

    Anderson, J.A.; Cole, K.K.

    The invention relates to a container for the safe air transport of plutonium having several intermediate wood layers and a load spreader intermediate an inner container and an outer shell for mitigation of shock during a hypothetical accident.

  1. Commercial Crew Transportation Capability

    NASA Image and Video Library

    2014-09-16

    NASA Administrator Charles Bolden listens to a reporter’s question after he announced the agency’s selection of Boeing and SpaceX to transport U.S. crews to and from the International Space Station using the Boeing CST-100 and the SpaceX Crew Dragon spacecraft, at NASA’s Kennedy Space Center in Cape Canaveral, Fla. on Tuesday, Sept. 16, 2014. These Commercial Crew Transportation Capability (CCtCap) contracts are designed to complete the NASA certification for a human space transportation system capable of carrying people into orbit. Once certification is complete, NASA plans to use these systems to transport astronauts to the space station and return them safely to Earth. Photo Credit: (NASA/Bill Ingalls)

  2. Rotorcraft air transportation

    NASA Technical Reports Server (NTRS)

    Gilbert, G. A.

    1983-01-01

    Intermodal relationships and the particular ways in which they affect public transportation applications of rotorcraft are addressed. Some aspects of integrated services and general comparisons with other transportation modes are reviewed. Two potential application scenarios are discussed: down-to-downtown rotorcraft service and urban public transport rotorcraft service. It is concluded that to integrate well with ground access modes community rotorcraft service should be limited stop service with published schedules, and operate on a few specific routes between a few specific destinations. For downtown-to-downtown service, time savings favorable to rotorcraft are benefits that reflect its more direct access, relatively higher line-haul travel speeds, and less circuitous travel. For the scenario of public transport within urban areas, first, improving cruise speeds has a limited potential due to allowing for a ""station spacing'' effect. Secondly, public acceptance of higher acceleration/deceleration rates may be just as effective as a technological innovation as achieving higher cruise speeds.

  3. Mechanisms of glutamate transport.

    PubMed

    Vandenberg, Robert J; Ryan, Renae M

    2013-10-01

    L-Glutamate is the predominant excitatory neurotransmitter in the mammalian central nervous system and plays important roles in a wide variety of brain functions, but it is also a key player in the pathogenesis of many neurological disorders. The control of glutamate concentrations is critical to the normal functioning of the central nervous system, and in this review we discuss how glutamate transporters regulate glutamate concentrations to maintain dynamic signaling mechanisms between neurons. In 2004, the crystal structure of a prokaryotic homolog of the mammalian glutamate transporter family of proteins was crystallized and its structure determined. This has paved the way for a better understanding of the structural basis for glutamate transporter function. In this review we provide a broad perspective of this field of research, but focus primarily on the more recent studies with a particular emphasis on how our understanding of the structure of glutamate transporters has generated new insights.

  4. Biofuel Ethanol Transport Risk

    EPA Science Inventory

    Ethanol production has increased rapidly over the last 10 years and many communities lack awareness of the increased and growing extent of biofuel transportation through their jurisdictions. These communities and their emergency responders may not have the information and resour...

  5. Pathways for Advective Transport

    DTIC Science & Technology

    2001-01-19

    the approach is given and an application to the Gulf of Mexico is described where the analysis precisely identifies the boundaries of coherent vortical structures as well as pathways for advective transport.

  6. Air transportation energy efficiency

    NASA Technical Reports Server (NTRS)

    Williams, L. J.

    1977-01-01

    The energy efficiency of air transportation, results of the recently completed RECAT studies on improvement alternatives, and the NASA Aircraft Energy Efficiency Research Program to develop the technology for significant improvements in future aircraft were reviewed.

  7. Commercial jet transport crashworthiness

    NASA Technical Reports Server (NTRS)

    Widmayer, E.; Brende, O. B.

    1982-01-01

    The results of a study to identify areas of research and approaches that may result in improved occupant survivability and crashworthiness of transport aircraft are given. The study defines areas of structural crashworthiness for transport aircraft which might form the basis for a research program. A 10-year research and development program to improve the structural impact resistance of general aviation and commercial jet transport aircraft is planned. As part of this program parallel studies were conducted to review the accident experience of commercial transport aircraft, assess the accident performance of structural components and the status of impact resistance technology, and recommend areas of research and development for that 10-year plan. The results of that study are also given.

  8. Determining transportation needs

    SciTech Connect

    Koutsopoulos, K.C.

    1980-07-01

    A lack of transportation represents a serious constraint to the physical and emotional well-being of many persons; the elderly, the handicapped, the poor, and the residents of rural areas are particularly vulnerable. There has been a significant preoccupation in transportation decisions with equity considerations that tend to be defined with reference to equality of rights, opportunities, and claims to public services. Recent government programs have favored the concept of public expenditures or services being distributed according to individual needs. This author examines the distribution-according-to-need concept and develops a framework for determining transportation needs. The resulting transportation-needs index could be utilized along with other indices (such as travel and mobility indices) as performance criteria for evaluation. 2 figures. (SAC)

  9. Biofuel Ethanol Transport Risk

    EPA Science Inventory

    Ethanol production has increased rapidly over the last 10 years and many communities lack awareness of the increased and growing extent of biofuel transportation through their jurisdictions. These communities and their emergency responders may not have the information and resour...

  10. Reengineering Defense Transportation

    DTIC Science & Technology

    1994-01-01

    TRANSCOM pledges to develop a new system that lives up to Winston Churchill’s dictum: "Victory is the beautiful bright coloured flower . Transport is the stem without which it could never have blossomed."

  11. Accident resistant transport container

    DOEpatents

    Andersen, John A.; Cole, James K.

    1980-01-01

    The invention relates to a container for the safe air transport of plutonium having several intermediate wood layers and a load spreader intermediate an inner container and an outer shell for mitigation of shock during a hypothetical accident.

  12. Latest in Campus Transportation

    ERIC Educational Resources Information Center

    Molloy, Larry

    1974-01-01

    Innovations in handling bicycles, autos, and buses are appearing on campuses across the country. Computer-driven shuttle cars and monorails are on the way. Provides information sources for more data about ongoing, innovative campus transportation programs. (Author)

  13. PICKing on transporters.

    PubMed

    Deken, S L; Beckman, M L; Quick, M W

    2001-11-01

    Plasma membrane neurotransmitter transporters are regulators of extracellular transmitter levels in brain and are the primary sites of action for several drugs of abuse and therapy. Studies are beginning to reveal how neurons use synaptic machinery to modulate these regulators.

  14. Transportation Network Topologies

    NASA Technical Reports Server (NTRS)

    Holmes, Bruce J.; Scott, John

    2004-01-01

    A discomforting reality has materialized on the transportation scene: our existing air and ground infrastructures will not scale to meet our nation's 21st century demands and expectations for mobility, commerce, safety, and security. The consequence of inaction is diminished quality of life and economic opportunity in the 21st century. Clearly, new thinking is required for transportation that can scale to meet to the realities of a networked, knowledge-based economy in which the value of time is a new coin of the realm. This paper proposes a framework, or topology, for thinking about the problem of scalability of the system of networks that comprise the aviation system. This framework highlights the role of integrated communication-navigation-surveillance systems in enabling scalability of future air transportation networks. Scalability, in this vein, is a goal of the recently formed Joint Planning and Development Office for the Next Generation Air Transportation System. New foundations for 21st thinking about air transportation are underpinned by several technological developments in the traditional aircraft disciplines as well as in communication, navigation, surveillance and information systems. Complexity science and modern network theory give rise to one of the technological developments of importance. Scale-free (i.e., scalable) networks represent a promising concept space for modeling airspace system architectures, and for assessing network performance in terms of scalability, efficiency, robustness, resilience, and other metrics. The paper offers an air transportation system topology as framework for transportation system innovation. Successful outcomes of innovation in air transportation could lay the foundations for new paradigms for aircraft and their operating capabilities, air transportation system architectures, and airspace architectures and procedural concepts. The topology proposed considers air transportation as a system of networks, within which

  15. Transportation Network Topologies

    NASA Technical Reports Server (NTRS)

    Holmes, Bruce J.; Scott, John M.

    2004-01-01

    A discomforting reality has materialized on the transportation scene: our existing air and ground infrastructures will not scale to meet our nation's 21st century demands and expectations for mobility, commerce, safety, and security. The consequence of inaction is diminished quality of life and economic opportunity in the 21st century. Clearly, new thinking is required for transportation that can scale to meet to the realities of a networked, knowledge-based economy in which the value of time is a new coin of the realm. This paper proposes a framework, or topology, for thinking about the problem of scalability of the system of networks that comprise the aviation system. This framework highlights the role of integrated communication-navigation-surveillance systems in enabling scalability of future air transportation networks. Scalability, in this vein, is a goal of the recently formed Joint Planning and Development Office for the Next Generation Air Transportation System. New foundations for 21PstP thinking about air transportation are underpinned by several technological developments in the traditional aircraft disciplines as well as in communication, navigation, surveillance and information systems. Complexity science and modern network theory give rise to one of the technological developments of importance. Scale-free (i.e., scalable) networks represent a promising concept space for modeling airspace system architectures, and for assessing network performance in terms of scalability, efficiency, robustness, resilience, and other metrics. The paper offers an air transportation system topology as framework for transportation system innovation. Successful outcomes of innovation in air transportation could lay the foundations for new paradigms for aircraft and their operating capabilities, air transportation system architectures, and airspace architectures and procedural concepts. The topology proposed considers air transportation as a system of networks, within

  16. Membrane Transport Phenomena (MTP)

    NASA Technical Reports Server (NTRS)

    Mason, Larry W.

    1997-01-01

    The third semi-annual period of the MTP project has been involved with performing experiments using the Membrane Transport Apparatus (MTA), development of analysis techniques for the experiment results, analytical modeling of the osmotic transport phenomena, and completion of a DC-9 microgravity flight to test candidate fluid cell geometries. Preparations were also made for the MTP Science Concept Review (SCR), held on 13 June 1997 at Lockheed Martin Astronautics in Denver. These activities are detailed in the report.

  17. Coal production and transportation

    SciTech Connect

    Not Available

    1981-01-01

    Sixteen papers covering a wide variety of topics relevant to today's coal industry and a panel discussion on railroad deregulation and coal unit train rates were presented at the Seventh Annual PLM Coal Conference on Coal Production and Transportation. This volume contains all of these papers, which cover the topics ranging from acid rain to project financing, from slurry pipelines to barge and railroad transportation, as well as the panel discussion. All papers have been abstracted and indexed.

  18. Fluid transport container

    DOEpatents

    DeRoos, Bradley G.; Downing, Jr., John P.; Neal, Michael P.

    1995-01-01

    An improved fluid container for the transport, collection, and dispensing of a sample fluid that maintains the fluid integrity relative to the conditions of the location at which it is taken. More specifically, the invention is a fluid sample transport container that utilizes a fitment for both penetrating and sealing a storage container under controlled conditions. Additionally, the invention allows for the periodic withdrawal of portions of the sample fluid without contamination or intermixing from the environment surrounding the sample container.

  19. Transport in Dump Combustors

    DTIC Science & Technology

    1986-08-20

    Ist June, 1983, initially for twelve months, but was extended for a further year to 31st Xay, 1985. The research, to be carried out at the University ...added seed particles to evaluate turbulent mass transport fluxes in the flame. A parellel theoretical study was to improve models of turbulent...transport and hence to identify a suitable model for combustor flow field calculations. However, the Grant was terminated, at the request of the University

  20. 2001 Industry Studies: Transportation

    DTIC Science & Technology

    2001-01-01

    November 2000.15 This downturn rippled throughout the truck manufacturing sector, where firms like Freightliner and Peterbilt laid off thousands of workers...million commercial trucks and buses, 190 million private automobiles, 1.5 million railroad freight and passenger cars and 7,600 certified air carrier...Motor Carrier – refers to roadway freight transportation provided by trucks . Industrial examples include: J. B. Hunt, Overnite Transportation, and Van

  1. Transportation fuels from wood

    SciTech Connect

    Baker, E.G.; Elliott, D.C.; Stevens, D.J.

    1980-01-01

    The various methods of producing transportation fuels from wood are evaluated in this paper. These methods include direct liquefaction schemes such as hydrolysis/fermentation, pyrolysis, and thermochemical liquefaction. Indirect liquefaction techniques involve gasification followed by liquid fuels synthesis such as methanol synthesis or the Fischer-Tropsch synthesis. The cost of transportation fuels produced by the various methods are compared. In addition, three ongoing programs at Pacific Northwest Laboratory dealing with liquid fuels from wood are described.

  2. Tape transport mechanism

    DOEpatents

    Groh, Edward F.; McDowell, William; Modjeski, Norbert S.; Keefe, Donald J.; Groer, Peter

    1979-01-01

    A device is provided for transporting, in a stepwise manner, tape between a feed reel and takeup reel. An indexer moves across the normal path of the tape displacing it while the tape on the takeup reel side of the indexer is braked. After displacement, the takeup reel takes up the displaced tape while the tape on the feed reel side of the indexer is braked, providing stepwise tape transport in precise intervals determined by the amount of displacement caused by the indexer.

  3. Nuclear transport and transcription.

    PubMed

    Komeili, A; O'Shea, E K

    2000-06-01

    The compartmentalization of DNA in the nucleus of eukaryotic cells establishes a connection between the nuclear transport machinery and the transcriptional apparatus. General transcription factors, as well as specific transcriptional activators and repressors, such as p53 and NF-AT, need to be imported into the nucleus following their translation. In addition, nuclear transport plays a crucial role in regulating the activity of many transcription factors.

  4. Fluid transport container

    DOEpatents

    DeRoos, B.G.; Downing, J.P. Jr.; Neal, M.P.

    1995-11-14

    An improved fluid container for the transport, collection, and dispensing of a sample fluid that maintains the fluid integrity relative to the conditions of the location at which it is taken. More specifically, the invention is a fluid sample transport container that utilizes a fitting for both penetrating and sealing a storage container under controlled conditions. Additionally, the invention allows for the periodic withdrawal of portions of the sample fluid without contamination or intermixing from the environment surrounding the sample container. 13 figs.

  5. [Recommendations for neonatal transport].

    PubMed

    Moreno Hernando, J; Thió Lluch, M; Salguero García, E; Rite Gracia, S; Fernández Lorenzo, J R; Echaniz Urcelay, I; Botet Mussons, F; Herranz Carrillo, G; Sánchez Luna, M

    2013-08-01

    During pregnancy, it is not always possible to identify maternal or foetal risk factors. Infants requiring specialised medical care are not always born in centres providing intensive care and will need to be transferred to a referral centre where intensive care can be provided. Therefore Neonatal Transport needs to be considered as part of the organisation of perinatal health care. The aim of Neonatal Transport is to transfer a newborn infant requiring intensive care to a centre where specialised resources and experience can be provided for the appropriate assessment and continuing treatment of a sick newborn infant. Intrauterine transfer is the ideal mode of transport when the birth of an infant with risk factors is diagnosed. Unfortunately, not all problems can be detected in advance with enough time to safely transfer a pregnant woman. Around 30- 50% of risk factors will be diagnosed during labour or soon after birth. Therefore, it is important to have the knowledge and resources to resuscitate and stabilise a newborn infant, as well as a specialised neonatal transport system. With this specialised transport it is possible to transfer newly born infants with the same level of care that they would receive if they had been born in a referral hospital, without increasing their risks or affecting the wellbeing of the newborn. The Standards Committee of the Spanish Society of Neonatology reviewed and updated recommendations for intrauterine transport and indications for neonatal transfer. They also reviewed organisational and logistic factors involved with performing neonatal transport. The Committee review included the type of personnel who should be involved; communication between referral and receiving hospitals; documentation; mode of transport; equipment to stabilise newly born infants; management during transfer, and admission at the referral hospital.

  6. Plant ABC Transporters

    PubMed Central

    Kang, Joohyun; Park, Jiyoung; Choi, Hyunju; Burla, Bo; Kretzschmar, Tobias; Lee, Youngsook; Martinoia, Enrico

    2011-01-01

    ABC transporters constitute one of the largest protein families found in all living organisms. ABC transporters are driven by ATP hydrolysis and can act as exporters as well as importers. The plant genome encodes for more than 100 ABC transporters, largely exceeding that of other organisms. In Arabidopsis, only 22 out of 130 have been functionally analyzed. They are localized in most membranes of a plant cell such as the plasma membrane, the tonoplast, chloroplasts, mitochondria and peroxisomes and fulfill a multitude of functions. Originally identified as transporters involved in detoxification processes, they have later been shown to be required for organ growth, plant nutrition, plant development, response to abiotic stresses, pathogen resistance and the interaction of the plant with its environment. To fulfill these roles they exhibit different substrate specifies by e.g. depositing surface lipids, accumulating phytate in seeds, and transporting the phytohormones auxin and abscisic acid. The aim of this review is to give an insight into the functions of plant ABC transporters and to show their importance for plant development and survival. PMID:22303277

  7. Ion transport in pigmentation

    PubMed Central

    Bellono, Nicholas W.; Oancea, Elena V.

    2014-01-01

    Skin melanocytes and ocular pigment cells contain specialized organelles called melanosomes, which are responsible for the synthesis of melanin, the major pigment in mammals. Defects in the complex mechanisms involved in melanin synthesis and regulation result in vision and pigmentation deficits, impaired development of the visual system,, and increased susceptibility to skin and eye cancers. Ion transport across cellular membranes is critical for many biological processes, including pigmentation, but the molecular mechanisms by which it regulates melanin synthesis, storage, and transfer are not understood. In this review we first discuss ion channels and transporters that function at the plasma membrane of melanocytes; in the second part we consider ion transport across the membrane of intracellular organelles, with emphasis on melanosomes. We discuss recently characterized lysosomal and endosomal ion channels and transporters associated with pigmentation phenotypes. We then review the evidence for melanosomal channels and transporters critical for pigmentation, discussing potential molecular mechanisms mediating their function. The studies investigating ion transport in pigmentation physiology open new avenues for future research and could reveal novel molecular mechanisms underlying melanogenesis. PMID:25034214

  8. Moss hair water transport

    NASA Astrophysics Data System (ADS)

    Pan, Zhao; Wu, Nan; Hurd, Randy; Thomson, Scott; Pitt, William; Truscott, Tadd

    2013-11-01

    We present an investigation of water transportation on a moss (Syntrichia caninervis) indigenous to temperate deserts. The moss typically appears to be in a dry, brown state, but is rehydrated by water during the wet season, making the desert green. Small hairs (500-2000 μm in length, and 40 μm in diameter, d) growing out from the tip of the moss leaves transport water back to the leaves. Through high speed observations and mathematical modeling it appears that this transportation is driven by two different mechanisms. 1) Droplet transport is achieved in three ways: i) A large (10d) droplet attached between two intersecting fibers will move toward the bases of the leaves by the changing angle between the two hairs. ii) The shape of the moss hair is conical, thicker at the base, producing a gradient that moves fluid (5d) toward the leaf similar to cactus spines. iii) We also observe that in some cases a Plateau-Rayleigh instability trigger a series of droplets moving toward the base. 2) Micro-grooves on the moss hair transport a film of water along the moss hair when larger droplets are not available. These various water transportation strategies combine to help the moss to survive in the desert and provide valuable insight.

  9. Ion transport in pigmentation.

    PubMed

    Bellono, Nicholas W; Oancea, Elena V

    2014-12-01

    Skin melanocytes and ocular pigment cells contain specialized organelles called melanosomes, which are responsible for the synthesis of melanin, the major pigment in mammals. Defects in the complex mechanisms involved in melanin synthesis and regulation result in vision and pigmentation deficits, impaired development of the visual system, and increased susceptibility to skin and eye cancers. Ion transport across cellular membranes is critical for many biological processes, including pigmentation, but the molecular mechanisms by which it regulates melanin synthesis, storage, and transfer are not understood. In this review we first discuss ion channels and transporters that function at the plasma membrane of melanocytes; in the second part we consider ion transport across the membrane of intracellular organelles, with emphasis on melanosomes. We discuss recently characterized lysosomal and endosomal ion channels and transporters associated with pigmentation phenotypes. We then review the evidence for melanosomal channels and transporters critical for pigmentation, discussing potential molecular mechanisms mediating their function. The studies investigating ion transport in pigmentation physiology open new avenues for future research and could reveal novel molecular mechanisms underlying melanogenesis.

  10. GOALS, STRATEGIES AND FIRST DISCOVERIES OF AO327, THE ARECIBO ALL-SKY 327 MHz DRIFT PULSAR SURVEY

    SciTech Connect

    Deneva, J. S.; Stovall, K.; Martinez, J. G.; Jenet, F.; McLaughlin, M. A.; Bates, S. D.; Bagchi, M.; Freire, P. C. C.

    2013-09-20

    We report initial results from AO327, a drift survey for pulsars with the Arecibo telescope at 327 MHz. The first phase of AO327 will cover the sky at declinations of –1° to 28°, excluding the region within 5° of the Galactic plane, where high scattering and dispersion make low-frequency surveys sub-optimal. We record data from a 57 MHz bandwidth with 1024 channels and 125 μs sampling time. The 60 s transit time through the AO327 beam means that the survey is sensitive to very tight relativistic binaries even with no acceleration searches. To date we have detected 44 known pulsars with periods ranging from 3 ms to 2.21 s and discovered 24 new pulsars. The new discoveries include 3 ms pulsars, three objects with periods of a few tens of milliseconds typical of young as well as mildly recycled pulsars, a nuller, and a rotating radio transient. Five of the new discoveries are in binary systems. The second phase of AO327 will cover the sky at declinations of 28°-38°. We compare the sensitivity and search volume of AO327 to the Green Bank North Celestial Cap survey and the GBT350 drift survey, both of which operate at 350 MHz.

  11. The new Arecibo Observatory Remote Optical Facility (AO-ROF) in Culebra Island, Puerto Rico: Current Status and Future Projects

    NASA Astrophysics Data System (ADS)

    Santos, P. T.

    2015-12-01

    The idea of establishing the Arecibo Observatory Remote Optical Facility (AO-ROF) in the island of Culebra is a solution to mitigate the ever cumulative quantity of cloud, fog, and rain that has distressed observations at the Arecibo Observatory (AO) during major optical campaigns and observations. Given Culebra Island's favorable geographical and climatological characteristics as its low elevation and geographic location, it appears to have more steady weather conditions than Arecibo, so therefore it provides more availability for optical observations. Placed on Culebra, optical instruments can observe the same thermospheric volume over AO sampled by the Incoherent Scatter Radar (ISR). This capability will become especially important during the High Frequency (HF) facility is on operation. Small and large scale irregularities created by that HF can be readily observed and tracked from the Culebra site, and simultaneous observations from AO of the same atmospheric volume will permit direct vector measurements of dynamical evolution of the irregularities. This work presents a discussion of the current status of AO-ROF facility, as well the future projects.

  12. Impact of solar activity on NAO and AO meteorological indices: 1950 - 2009. (Slovak Title: Vplyv slnečnej aktivity na meteorologické indexy NAO a AO: 1950 - 2009)

    NASA Astrophysics Data System (ADS)

    Dorotovič, I.; Trigo, I.

    2010-12-01

    Many phenomena on the Sun, in the interplanetary and near Earth space play an important role in the solar-terrestrial system. An increasing number of studies indicate that variations in the solar activity (SA) may have significant impact on the atmosphere, spanning from the upper layers directly affected by space weatherthrough the stratospheric ozone layer down to the troposphere. The goal of this study is to identify possible impact of the SA on the main modes of atmospheric variability in the Northern Hemisphere and the Northern Atlantic region in particular. As a first step, we have analysed the statistical distribution of the indices describing the North Atlantic Oscillation (NAO) and the Arctic Oscillation (AO) during various phases of the SA. We have used the daily NAO and monthly AO indices available from the NOAA Climate Center (CPC). The AO probability density functions (PDFs) are analysed on monthly and quarterly scales, while the NAO PDFs are analysed on weekly, monthly and quarterly scales.

  13. FlyEyes: integrating CCID-35 into PUEO AO system at CFHT

    NASA Astrophysics Data System (ADS)

    Ho, Kevin K. Y.; Cuillandre, Jean-Charles; Lin, Chueh-Jen; Benedict, Tom; Lai, Olivier; Ward, Jeff; Salmon, Derrick; Luppino, Gerry; Beletic, James; Dorn, Reinhold; Puget, Pascal; Burke, Barry; Wang, Shiang-Yu

    2006-06-01

    A project to upgrade PUEO, the CFHT AO system, was first proposed in 2002. As part of the upgrade effort, a technology project was conceived to evaluate and characterize the backside-illuminated CCID-35 detector as suitable a replacement for the array of avalanche photo diode modules (APDs) in the curvature wavefront sensor. The CCID-35 was envisioned to replace an array of expensive APDs thus providing a cost-effective means of upgrading PUEO to a higher-order system. Work on the project, dubbed FlyEyes, occurred sporadically until Oct 2005 but substantial progress has been made since. This paper was intended to report on the performance of FlyEyes in PUEO but unfortunately the instrument was not ready for tests at the time of this writing. This paper summarizes the progress made on the project thus far and touches upon some of the difficulties encountered.

  14. Optical observations of the outburst of blazar AO 0235+16

    NASA Astrophysics Data System (ADS)

    Balonek, T. J.; Lam, M. T.

    2008-09-01

    Observations at the Colgate University Foggy Bottom Observatory confirm the spectacular nature of the current optical outburst in the blazar AO 0235+16 reported by Villata et al (ATEL #1724). The blazar has reached a brightness level, R ~ 14.1, comparable to outbursts in 1990-91, 1992, 1998, and 2007. Preliminary reductions of CCD images indicate the blazar was at R ~ 16.2 on September 4.2 (UT), R ~ 15.4 on September 20.2 - observations hindered by the close proximity of the Moon, R ~ 15.0 on September 21.2, R ~ 14.2 on September 23.2, and R ~ 14.1 on September 24.2.

  15. NIX, the imager for ERIS: the AO instrument for the VLT

    NASA Astrophysics Data System (ADS)

    Pearson, David; Taylor, William; Davies, Ric; MacIntosh, Mike; Henry, David; Lunney, David; Waring, Chris; Gao, Xiaofeng; Lightfoot, John; Glauser, Adrian M.; Quanz, Sascha P.; Meyer, Michael R.; Schmid, Hans Martin; March, Stephen; Bachmann, Walter; Feuchtgruber, Helmut; George, Elizabeth; Sturm, Eckhard; Biller, Beth; Hinckley, Sasha; Kenworthy, Matthew; Amico, Paola; Glindemann, Andreas; Kasper, Marcus; Kuntschner, Harald; Dorn, Reinhold; Egner, Sebastian

    2016-08-01

    ERIS will be the next-generation AO facility on the VLT, combining the heritage of NACO imaging, with the spectroscopic capabilities of an upgraded SINFONI. Here we report on the all-new NIX imager that will deliver diffraction-limited imaging from the J to M band. The instrument will be equipped with both Apodizing Phase Plates and Sparse Aperture Masks to provide high-angular resolution imagery, especially suited for exoplanet imaging and characterization. This paper provides detail on the instrument's design and how it is suited to address a broad range of science cases, from detailed studies of the galactic centre at the highest resolutions, to studying detailed resolved stellar populations.

  16. Mononuclear anionic AO(2)X(3) compounds with non-VSEPR structure.

    PubMed

    García-Monforte, M Angeles; Baya, Miguel; Betoré, M Pilar; Martín, Antonio; Menjón, Babil

    2014-05-28

    The molybdenyl compound [NBu4][MoO2(C6F5)3] () has been obtained by low-temperature treatment of MoO2Cl2 with LiC6F5 in Et2O followed by addition of [NBu4]Br. This compound of the (AO2X3)(-) type shows an unusual five-coordinate structure not lying in the Berry-pseudorotation path: it can be described rather as an edge-capped tetrahedron (TE-5). The same kind of structure has been found by DFT calculations to be the most energetically favored for the mononuclear (MoO2X3)(-) model species, where X = H, Cl or CN. Compound exhibits marked stereochemical stability, as it shows no sign of exchange between chemically inequivalent C6F5 groups even at 150 °C in dmf solution ((19)F NMR spectroscopy).

  17. Development and operation of an off-limb solar AO system

    NASA Astrophysics Data System (ADS)

    Taylor, Gregory Edward

    2014-01-01

    An Adaptive Optics system capable of locking-on to off-limb prominence structure has been proven successful. It has been shown to allow for diffraction limited spectroscopy and polarimetry of prominence structure. Spectroscopic data obtained using the Off-Limb AO system have been shown to contain a trove of information regarding the nature of solar prominences. In particular a Rayleigh-Taylor instability was seen in part of this data set. Such instabilities, and the rising plumes that result from them, are thought to be critical clues to the longterm persistence of quiescent solar prominences. This adaptive optics system will allow scientists to come one step closer to understanding the true nature of solar prominences.

  18. LDEF (Postflight), AO139A : Growth of Crystals From Solutions in Low Gravity, Tray G06

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Postflight), AO139A : Growth of Crystals From Solutions in Low Gravity, Tray G06 The postflight photograph was taken in the SAEF II at KSC after the experiment tray was removed from the LDEF. The experiment tray flanges have become discolored with a light tan stain except where the tray clamp blocks were located. A darker stain appears to exist at the intersection of the white cover plate and the upper left flange of the experiment tray. The Crystal Growth experiment appears to have survived the extended mission with no visible damage. The experiment cover plate, originally white, appears to be discolored by a very light brown stain but is intact and securely in place.

  19. LDEF (Postflight), AO015 : Free-Flyer Biostack Experiment, Tray G02

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Postflight), AO015 : Free-Flyer Biostack Experiment, Tray G02 The post flight photograph was taken in the SAEF II at KSC after the experiment tray was removed from the LDEF. The experiment tray flanges and sidewalls have become discolored with a light tan stain except where the tray clamp blocks were located. The Biostack experiment appears to have survived the extended mission with no visible damage. The experiment housings are intact and all hardware is securely in place. The detector housings appear to be discolored with a stain similar to that on the tray hardware. The exposed Kapton H foil covering windows in two (2) detector housings do not appear to have sustained damage dur ing the extended mission. The perforated dome on two (2) of the detector housings has a slight tan discoloration but no indication of damage.

  20. Toward a large lightweight mirror for AO: development of a 1m Ni coated CFRP mirror

    NASA Astrophysics Data System (ADS)

    Thompson, S. J.; Doel, A. P.; Brooks, D.; Strangwood, M.

    2008-07-01

    We present our recent developments towards the construction of a large, thin, single-piece mirror for adaptive optics (AO). Our current research program aims to have completed fabrication and testing of a 1m diameter, nickel coated carbon-fibre reinforced cyanate ester resin mirror by the last quarter of 2009. This composite mirror material is being developed to provide a lightweight and robust alternative to thin glass shell mirrors, with the challenge of future large deformable mirrors such as the 2.5m M4 on the E-ELT in mind. A detailed analysis of the material properties of test mirror samples is being performed at the University of Birmingham (UK), the first results of which are discussed and presented here. We discuss the project progress achieved so far, including fabrication of the 1m flat moulds for the replication process, manufacturing and testing methods for 20 cm diameter sample mirrors and system simulations.

  1. ShaneAO: wide science spectrum adaptive optics system for the Lick Observatory

    NASA Astrophysics Data System (ADS)

    Gavel, Donald; Kupke, Renate; Dillon, Daren; Norton, Andrew; Ratliff, Chris; Cabak, Jerry; Phillips, Andrew; Rockosi, Connie; McGurk, Rosalie; Srinath, Srikar; Peck, Michael; Deich, William; Lanclos, Kyle; Gates, John; Saylor, Michael; Ward, Jim; Pfister, Terry

    2014-07-01

    A new high-order adaptive optics system is now being commissioned at the Lick Observatory Shane 3-meter telescope in California. This system uses a high return efficiency sodium beacon and a combination of low and high-order deformable mirrors to achieve diffraction-limited imaging over a wide spectrum of infrared science wavelengths covering 0.8 to 2.2 microns. We present the design performance goals and the first on-sky test results. We discuss several innovations that make this system a pathfinder for next generation AO systems. These include a unique woofer-tweeter control that provides full dynamic range correction from tip/tilt to 16 cycles, variable pupil sampling wavefront sensor, new enhanced silver coatings developed at UC Observatories that improve science and LGS throughput, and tight mechanical rigidity that enables a multi-hour diffraction-limited exposure in LGS mode for faint object spectroscopy science.

  2. Robotic Laser Adaptive Optics Imaging of 715 Kepler Exoplanet Candidates Using Robo-AO

    NASA Astrophysics Data System (ADS)

    Law, Nicholas M.; Morton, Tim; Baranec, Christoph; Riddle, Reed; Ravichandran, Ganesh; Ziegler, Carl; Johnson, John Asher; Tendulkar, Shriharsh P.; Bui, Khanh; Burse, Mahesh P.; Das, H. K.; Dekany, Richard G.; Kulkarni, Shrinivas; Punnadi, Sujit; Ramaprakash, A. N.

    2014-08-01

    The Robo-AO Kepler Planetary Candidate Survey is observing every Kepler planet candidate host star with laser adaptive optics imaging to search for blended nearby stars, which may be physically associated companions and/or responsible for transit false positives. In this paper, we present the results from the 2012 observing season, searching for stars close to 715 Kepler planet candidate hosts. We find 53 companions, 43 of which are new discoveries. We detail the Robo-AO survey data reduction methods including a method of using the large ensemble of target observations as mutual point-spread-function references, along with a new automated companion-detection algorithm designed for large adaptive optics surveys. Our survey is sensitive to objects from ≈0.''15 to 2.''5 separation, with magnitude differences up to Δm ≈ 6. We measure an overall nearby-star probability for Kepler planet candidates of 7.4% ± 1.0%, and calculate the effects of each detected nearby star on the Kepler-measured planetary radius. We discuss several Kepler Objects of Interest (KOIs) of particular interest, including KOI-191 and KOI-1151, which are both multi-planet systems with detected stellar companions whose unusual planetary system architecture might be best explained if they are "coincident multiple" systems, with several transiting planets shared between the two stars. Finally, we find 98% confidence evidence that short-period giant planets are two to three times more likely than longer-period planets to be found in wide stellar binaries.

  3. A History of Correlations Between Optical and Radio Outbursts in the Blazar AO 0235+164

    NASA Astrophysics Data System (ADS)

    McGrath, E. J.; Balonek, T. J.; Brandt, T. J.

    2000-05-01

    We present a ten year optical light curve for the blazar AO 0235+164 from 1989 through mid-1999. Observations were conducted at the Foggy Bottom Observatory at Colgate University using a sixteen inch Cassegrain telescope and CCD camera. Herein we note the correlations between optical and radio variations (radio observations obtained at the University of Michigan Radio Astronomy Observatory, UMRAO). MacLeod, Andrew, and Harvey (1976); Ledden, Aller, and Dent (1976); and Rieke et al. (1976) first noted a correlation between the optical and radio variations in a 1975 outburst of AO 0235+164. Balonek and Dent (1980) showed a second correlation in a 1979 outburst. Subsequent optical outbursts and further optical-radio correlations have been studied by several authors. We study the long and short time scale variations in four additional optical outbursts in 1990, 1991, 1992, and 1998. We find that some of the bursts appear to be strongly correlated with radio bursts, while others do not exhibit simple correlations. Different physical phenomena may be needed in order to explain the differences in these outbursts. In the correlated cases, the optical burst appears to either nearly coincide with a radio burst, or precede a subsequent radio burst by a few months. The time scales of the outbursts agree with the generally accepted model of Blandford and Konigl (1979) of a relativistic shock propagating down a jet. In addition, intra-night variability is seen during these outbursts on much shorter time scales and is most likely caused by another phenomenon.

  4. Robotic laser adaptive optics imaging of 715 Kepler exoplanet candidates using Robo-AO

    SciTech Connect

    Law, Nicholas M.; Ziegler, Carl; Morton, Tim; Riddle, Reed; Tendulkar, Shriharsh P.; Bui, Khanh; Dekany, Richard G.; Kulkarni, Shrinivas; Punnadi, Sujit; Baranec, Christoph; Ravichandran, Ganesh; Johnson, John Asher; Burse, Mahesh P.; Das, H. K.; Ramaprakash, A. N.

    2014-08-10

    The Robo-AO Kepler Planetary Candidate Survey is observing every Kepler planet candidate host star with laser adaptive optics imaging to search for blended nearby stars, which may be physically associated companions and/or responsible for transit false positives. In this paper, we present the results from the 2012 observing season, searching for stars close to 715 Kepler planet candidate hosts. We find 53 companions, 43 of which are new discoveries. We detail the Robo-AO survey data reduction methods including a method of using the large ensemble of target observations as mutual point-spread-function references, along with a new automated companion-detection algorithm designed for large adaptive optics surveys. Our survey is sensitive to objects from ≈0.''15 to 2.''5 separation, with magnitude differences up to Δm ≈ 6. We measure an overall nearby-star probability for Kepler planet candidates of 7.4% ± 1.0%, and calculate the effects of each detected nearby star on the Kepler-measured planetary radius. We discuss several Kepler Objects of Interest (KOIs) of particular interest, including KOI-191 and KOI-1151, which are both multi-planet systems with detected stellar companions whose unusual planetary system architecture might be best explained if they are 'coincident multiple' systems, with several transiting planets shared between the two stars. Finally, we find 98% confidence evidence that short-period giant planets are two to three times more likely than longer-period planets to be found in wide stellar binaries.

  5. Keck II laser guide star AO system and performance with the TOPTICA/MPBC laser

    NASA Astrophysics Data System (ADS)

    Chin, Jason C. Y.; Wizinowich, Peter; Wetherell, Ed; Lilley, Scott; Cetre, Sylvain; Ragland, Sam; Medeiros, Drew; Tsubota, Kevin; Doppmann, Greg; Otarola, Angel; Wei, Kai

    2016-07-01

    The Keck II Laser Guide Star (LGS) Adaptive Optics (AO) System was upgraded from a dye laser to a TOPTICA/MPBC Raman-Fibre Amplification (RFA) laser in December 2015. The W. M. Keck Observatory (WMKO) has been operating its AO system with a LGS for science since 2004 using a first generation 15 W dye laser. Using the latest diode pump laser technology, Raman amplification, and a well-tuned second harmonic generator (SHG), this Next Generation Laser (NGL) is able to produce a highly stable 589 nm laser beam with the required power, wavelength and mode quality. The beam's linear polarization and continuous wave format along with optical back pumping are designed to improve the sodium atom coupling efficiency over previously operated sodium-wavelength lasers. The efficiency and operability of the new laser has also been improved by reducing its required input power and cooling, size, and the manpower to operate and maintain it. The new laser has been implemented on the telescope's elevation ring with its electronics installed on a new Nasmyth sub-platform, with the capacity to support up to three laser systems for future upgrades. The laser is projected from behind the telescope's secondary mirror using the recently implemented center launch system (CLS) to reduce LGS spot size. We will present the new laser system and its performance with respect to power, stability, wavelength, spot size, optical repumping, polarization, efficiency, and its return with respect to pointing alignment to the magnetic field. Preliminary LGSAO performance is presented with the system returning to science operations. We will also provide an update on current and future upgrades at the WMKO.

  6. Interdecadal changes in the Asian winter monsoon variability and its relationship with ENSO and AO

    NASA Astrophysics Data System (ADS)

    Yun, Kyung-Sook; Seo, Ye-Won; Ha, Kyung-Ja; Lee, June-Yi; Kajikawa, Yoshiyuki

    2014-08-01

    Interdecadal changes in the Asian winter monsoon (AWM) variability are investigated using three surface air temperature datasets for the 55-year period of 1958-2012 from (1) the National Centers for Environmental Prediction-National Center for Atmospheric Research reanalysis 1 (NCEP), (2) combined datasets from the European Centre for Medium-range Weather Forecasts (ECMWF) 40-yr reanalysis and interim data (ERA), and (3) Japanese 55-year reanalysis (JRA). Particular attention has been paid to the first four empirical orthogonal function (EOF) modes of the AWM temperature variability that together account for 64% of the total variance and have been previously identified as predictable modes. The four modes are characterized as follows: the first mode by a southern warming over the Indo-western Pacific Ocean associated with a gradually increasing basin-wide warming trend; the second mode by northern warming with the interdecadal change after the late 1980s; the third and fourth modes by north-south triple pattern, which reveal a phase shift after the late 1970s. The three reanalyses agree well with each other when producing the first three modes, but show large discrepancy in capturing both spatial and temporal characteristics of the fourth mode. It is therefore considered that the first three leading modes are more reliable than the rest higher modes. Considerable interdecadal changes are found mainly in the first two modes. While the first mode shows gradually decreasing variance, the second mode exhibits larger interannual variance during the recent decade. In addition, after the late 1970s, the first mode has a weakening relationship with the El Niño-Southern Oscillation (ENSO) whereas the second mode has strengthening association with the Artic Oscillation (AO). This indicates an increasing role of AO but decreasing role of ENSO on the AWM variability. A better understanding of the interdecadal change in the dominant modes would contribute toward advancing in

  7. Interannual variations of the blocking high over the Ural Mountains and its association with the AO/NAO in boreal winter

    NASA Astrophysics Data System (ADS)

    Li, Chao; Zhang, Qingyun; Ji, Liren; Peng, Jingbei

    2012-04-01

    This paper analyzes interannual variations of the blocking high over the Ural Mountains in the boreal winter and their association with the Arctic Oscillation/North Atlantic Oscillation (AO/NAO). In January, the relationship between the Ural blocking high (UR) and the AO index is statistically significant. The UR tends to occur more frequently and with greater strength during negative AO periods. Some strong URs also occur during positive AO phases (positive UR-AO events), as in January 2008. This paper discusses the characteristics of atmospheric circulation in the cases of positive UR-AO events and contrast cases (negative UR-AO events). The eastward extending of the Icelandic Low (IL) center and the associated NAO dipole anomaly pattern in the upstream region may play a more important role for the UR-AO events. When the center of the IL shifts eastward to 30°W, the amplitude of zonal wavenumber 2 (wavenumber 3) is intensified in the positive (negative) UR-AO events, which favors positive (negative) height anomalies over the Urals. Further analyses indicate that the intensified zonal wind in high latitudes and weakened zonal wind in midlatitudes over the North Atlantic Ocean render the eastward shift of the IL and the NAO dipole anomaly pattern. The Ural blocking in January 2008 bears similar characteristics to the positive UR-AO events.

  8. Transient Transport in Binary and Ternary Semiconductors.

    DTIC Science & Technology

    1986-02-27

    transport; Semiconductors, Microelectronics, Quantum transport , Boltzmann transport, Drift and diffusion, Gallium arsende, Aluminum gallium arsenide, Indium gallium arsenide, and Transient transport.

  9. Transportation Anslysis Simulation System

    SciTech Connect

    2004-08-23

    TRANSIMS version 3.1 is an integrated set of analytical and simulation models and supporting databases. The system is designed to create a virtual metropolitan region with representation of each of the region’s individuals, their activities and the transportation infrastructure they use. TRANSIMS puts into practice a new, disaggregate approach to travel demand modeling using agent-based micro-simulation technology. TRANSIMS methodology creates a virtual metropolitan region with representation of the transportation infrastructure and the population, at the level of households and individual travelers. Trips a planned to satisfy the population’s activity pattems at the individual traveler level. TRANSIMS then simulates the movement of travelers and vehicles across the transportation network using multiple modes, including car, transit, bike and walk, on a second-by-second basis. Metropolitan planners must plan growth of their cities according to the stringent transportation system planning requirements of the Interniodal Surface Transportation Efficiency Act of 1991, the Clean Air Act Amendments of 1990 and other similar laws and regulations. These require each state and its metropotitan regions to work together to develop short and long term transportation improvement plans. The plans must (1) estimate the future transportation needs for travelers and goods movements, (2) evaluate ways to manage and reduce congestion, (3) examine the effectiveness of building new roads and transit systems, and (4) limit the environmental impact of the various strategies. The needed consistent and accurate transportation improvement plans require an analytical capability that properly accounts for travel demand, human behavior, traffic and transit operations, major investments, and environmental effects. Other existing planning tools use aggregated information and representative behavior to predict average response and average use of transportation facilities. They do not account

  10. Bioreactor Mass Transport Studies

    NASA Technical Reports Server (NTRS)

    Kleis, Stanley J.; Begley, Cynthia M.

    1997-01-01

    The objectives of the proposed research efforts were to develop both a simulation tool and a series of experiments to provide a quantitative assessment of mass transport in the NASA rotating wall perfused vessel (RWPV) bioreactor to be flown on EDU#2. This effort consisted of a literature review of bioreactor mass transport studies, the extension of an existing scalar transport computer simulation to include production and utilization of the scalar, and the evaluation of experimental techniques for determining mass transport in these vessels. Since mass transport at the cell surface is determined primarily by the relative motion of the cell assemblage and the surrounding fluid, a detailed assessment of the relative motion was conducted. Results of the simulations of the motion of spheres in the RWPV under microgravity conditions are compared with flight data from EDU#1 flown on STS-70. The mass transport across the cell membrane depends upon the environment, the cell type, and the biological state of the cell. Results from a literature review of cell requirements of several scalars are presented. As a first approximation, a model with a uniform spatial distribution of utilization or production was developed and results from these simulations are presented. There were two candidate processes considered for the experimental mass transport evaluations. The first was to measure the dissolution rate of solid or gel beads. The second was to measure the induced fluorescence of beads as a stimulant (for example hydrogen peroxide) is infused into the vessel. Either technique would use video taped images of the process for recording the quantitative results. Results of preliminary tests of these techniques are discussed.

  11. Cyclic GMP transporters.

    PubMed

    Sager, Georg

    2004-11-01

    The biokinetics of guanosine 3',5'-cyclic monophosphate (cGMP) is characterized by three distinct processes: synthesis by guanylate cyclases (GCs), conversion of cGMP to GMP by cyclic nucleotide phosphodiesterases (PDEs) and the excretion of unchanged cGMP by transport proteins in the cell membrane. Efflux is observed in virtually all cell types including cells which originate from brain. Studies of intact cells, in which metabolic inhibitors and probenecid reduced extrusion of cGMP and wherein cGMP was extruded against concentration gradients, indicated the existence of ATP requiring organic anion transport system(s). Functional studies of inside-out vesicles have revealed cGMP transport systems wherein translocation is coupled to hydrolysis of ATP. The extrusion of cGMP is inhibited by a number of unrelated compounds and this indicates that cGMP is substrate for multispecific transporters. Recent transfection studies suggest that members of the MRP (multidrug resistance protein) family; MRP4, MRP5 and MRP8 translocate cGMP across the cell membrane. Many of the MRPs have been detected in brain. In addition tertiary active transport by the organic anion transporter family has also been identified. At least one member (OAT1) shows relative high affinity for cGMP and is also expressed in brain. The biological significance of cGMP transporters has to be clarified. Their role in cGMP biokinetics, being responsible for one of the cellular elimination pathways, is well established. However, there is growing evidence that extracellular cGMP has effects on cell physiology and pathophysiology by an auto- or paracrine mechanism.

  12. Fracture and dislocation classification compendium for children: the AO pediatric comprehensive classification of long bone fractures (PCCF).

    PubMed

    Slongo, Theddy F; Audigé, Laurent

    2007-01-01

    The AO Pediatric Expert Group and the AO Pediatric Classification Group, in cooperation with the AO Investigation and Documentation Group introduce and present the first comprehensive classification of pediatric long bone fractures. The anatomy is related to the 4 long bones and their 3 segments defined as proximal (1), shaft (2) and distal (3). It is further described by the fracture subsegment recorded as epiphyseal (E), metaphyseal (M) and diaphyseal (D), whereby proximal and distal fractures are classified as E or M and shaft fractures are always D. The distinction between metaphyseal and diaphyseal fractures is achieved by localizing the center of fracture lines with regard to a square drawn over the respective growth plates. The morphology of the fracture is documented by a subsegment-specific child pattern code, a severity code as well as an additional code for displacement of specific fractures such as supracondylar fractures and radial heads. The classification process requires trained observers to read standard radiographic images.

  13. Intelligent Transport Systems in the Management of Road Transportation

    NASA Astrophysics Data System (ADS)

    Kalupová, Blanka; Hlavoň, Ivan

    2016-11-01

    Extension of European Union causes increase of free transfer of people and goods. At the same time they raised the problems associated with the transport, e.g. congestion and related accidents on roads, air traffic delays and more. To increase the efficiency and safety of transport, the European Commission supports the introduction of intelligent transport systems and services in all transport sectors. Implementation of intelligent transport systems and services in the road transport reduces accident frequency, increases the capacity of existing infrastructure and reduces congestions. Use of toll systems provides resources needed for the construction and operation of a new road network, improves public transport, cycling transport and walking transport, and also their multimodal integration with individual car transport.

  14. Subaru SCExAO First-Light Direct Imaging of a Young Debris Disk around HD 36546

    NASA Technical Reports Server (NTRS)

    Currie, Thayne; Guyon, Olivier; Tamura, Motohide; Kudo, Tomoyuki; Jovanovic, Nemanja; Lozi, Julien; Schlieder, Joshua E.; Brandt, TImothy D.; Kuhn, Jonasa; Serabyn, Eugene; hide

    2017-01-01

    We present H-band scattered light imaging of a bright debris disk around the A0 star HD 36546 obtained from the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system with data recorded by the HiCIAO camera using the vector vortex coronagraph. SCExAO traces the disk from r approximately 0 3 to r approximately 0".3 to r approximately 1" (34-114 au). The disk is oriented in a near east west direction (PA approximately 75deg), is inclined by I approximately 70deg-75deg, and is strongly forward-scattering(g greater than 0.5). It is an extended disk rather than a sharp ring; a second, diffuse dust population extends from the disks eastern side. While HD 36546 intrinsic properties are consistent with a wide age range (t approximately 1-250 Myr), its kinematics and analysis of coeval stars suggest a young age (310 Myr) and a possible connection to Taurus-Aurigas star formation history. SCExAOs planet-to-star contrast ratios are comparable to the first-light Gemini Planet Imager contrasts; for an age of 10 Myr, we rule out planets with masses comparable to HR 8799 b beyond a projected separation of 23 au. A massive icy planetesimal disk or an unseen super-Jovian planet at r greater than 20 au may explain the disks visibility. The HD 36546 debris disk may be the youngest debris disk yet imaged, is the first newly identified object from the now-operational SCExAO extreme AO system, is ideally suited for spectroscopic follow-up with SCExAO/CHARIS in 2017, and may be a key probe of icy planet formation and planet disk interactions.

  15. A1Ao-ATP Synthase of Methanobrevibacter ruminantium Couples Sodium Ions for ATP Synthesis under Physiological Conditions*

    PubMed Central

    McMillan, Duncan G. G.; Ferguson, Scott A.; Dey, Debjit; Schröder, Katja; Aung, Htin Lin; Carbone, Vincenzo; Attwood, Graeme T.; Ronimus, Ron S.; Meier, Thomas; Janssen, Peter H.; Cook, Gregory M.

    2011-01-01

    An unresolved question in the bioenergetics of methanogenic archaea is how the generation of proton-motive and sodium-motive forces during methane production is used to synthesize ATP by the membrane-bound A1Ao-ATP synthase, with both proton- and sodium-coupled enzymes being reported in methanogens. To address this question, we investigated the biochemical characteristics of the A1Ao-ATP synthase (MbbrA1Ao) of Methanobrevibacter ruminantium M1, a predominant methanogen in the rumen. Growth of M. ruminantium M1 was inhibited by protonophores and sodium ionophores, demonstrating that both ion gradients were essential for growth. To study the role of these ions in ATP synthesis, the ahaHIKECFABD operon encoding the MbbrA1Ao was expressed in Escherichia coli strain DK8 (Δatp) and purified yielding a 9-subunit protein with an SDS-stable c oligomer. Analysis of the c subunit amino acid sequence revealed that it consisted of four transmembrane helices, and each hairpin displayed a complete Na+-binding signature made up of identical amino acid residues. The purified MbbrA1Ao was stimulated by sodium ions, and Na+ provided pH-dependent protection against inhibition by dicyclohexylcarbodiimide but not tributyltin chloride. ATP synthesis in inverted membrane vesicles lacking sodium ions was driven by a membrane potential that was sensitive to cyanide m-chlorophenylhydrazone but not to monensin. ATP synthesis could not be driven by a chemical gradient of sodium ions unless a membrane potential was imposed. ATP synthesis under these conditions was sensitive to monensin but not cyanide m-chlorophenylhydrazone. These data suggest that the M. ruminantium M1 A1Ao-ATP synthase exhibits all the properties of a sodium-coupled enzyme, but it is also able to use protons to drive ATP synthesis under conditions that favor proton coupling, such as low pH and low levels of sodium ions. PMID:21953465

  16. Winter AO/NAO modifies summer ocean heat content and monsoonal circulation over the western Indian Ocean

    NASA Astrophysics Data System (ADS)

    Gong, Dao-Yi; Guo, Dong; Li, Sang; Kim, Seong-Joong

    2017-02-01

    This paper analyzes the possible influence of boreal winter Arctic Oscillation/North Atlantic Oscillation (AO/ NAO) on the Indian Ocean upper ocean heat content in summer as well as the summer monsoonal circulation. The strong interannual co-variation between winter 1000-hPa geopotential height in the Northern Hemisphere and summer ocean heat content in the uppermost 120 m over the tropical Indian Ocean was investigated by a singular decomposition analysis for the period 1979-2014. The second paired-modes explain 23.8% of the squared covariance, and reveal an AO/NAO pattern over the North Atlantic and a warming upper ocean in the western tropical Indian Ocean. The positive upper ocean heat content enhances evaporation and convection, and results in an anomalous meridional circulation with ascending motion over 5°S-5°N and descending over 15°-25°N. Correspondingly, in the lower troposphere, significantly anomalous northerly winds appear over the western Indian Ocean north of the equator, implying a weaker summer monsoon circulation. The off-equator oceanic Rossby wave plays a key role in linking the AO/NAO and the summer heat content anomalies. In boreal winter, a positive AO/NAO triggers a down-welling Rossby wave in the central tropical Indian Ocean through the atmospheric teleconnection. As the Rossby wave arrives in the western Indian Ocean in summer, it results in anomalous upper ocean heating near the equator mainly through the meridional advection. The AO/NAO-forced Rossby wave and the resultant upper ocean warming are well reproduced by an ocean circulation model. The winter AO/NAO could be a potential season-lead driver of the summer atmospheric circulation over the northwestern Indian Ocean.

  17. Bioremediation of bisphenol-A polluted soil by Sphingomonas bisphenolicum AO1 and the microbial community existing in the soil.

    PubMed

    Matsumura, Yoshinobu; Akahira-Moriya, Ayako; Sasaki-Mori, Miho

    2015-01-01

    Bisphenol A (BPA, 2,2'-Bis (4-hydroxyphenyl) propane) is an artificial pollutant that is easily detected in soil and water environments. BPA decomposition and removal from the environment is relatively difficult due to its stability. This study evaluated the BPA decomposition and removal activities of the microbial community existing in the soil with or without Sphingomonas bisphenolicum AO1, and revealed the toxic effects of BPA towards the microbial community. The microbial community in soil was able to degrade BPA at 1.0 mg·g(-1) soil or lower, although its degradation was slow. On the other hand, BPA at more than 10 mg·g(-1) soil was not only degraded by the microbial community but also decreased its diversity, suggesting that BPA is harmful to many microorganisms. PCR-TTGE analysis and the cloned 16S rRNA gene sequence analysis indicated that Sphingomonadales, Xanthomonadales, Burkholderiales and Pseudomonadales in the microbial community might independently or cooperatively degrade BPA. On the other hand, supplementation with strain AO1 was able to significantly improve the BPA decomposition activity of the microbial community in soil even at 10 mg BPA·g(-1) soil, although BPA at 100 mg·g(-1) soil overwhelmed the BPA decomposition activity of strain AO1. Furthermore, it was also concluded that strain AO1 could not inhabit BPA purified soil after decomposition of BPA by strain AO1 and the soil microbial community, suggesting that the application of strain AO1 could be a low-burden method for the decomposition and removal of BPA from the natural environment.

  18. Lagrangian Sediment Transport Model

    NASA Astrophysics Data System (ADS)

    Maderych, V.; Brovchenko, I.; Fenical, S.; Shepsis, V.

    2004-12-01

    A new two-dimensional Lagrangian sediment transport model was developed to simulate a wide-range of sediment transport processes, including sediment mobility under combined current and wave action, sediment transport and bed change under wave and currents effects, sediment transport patterns at nearshore coastal and offshore structures, and turbidity and sediment motion during dredging and dredged material placement. The Lagrangian technique was used to simulate transport of sediments, deposition, and re-suspension. The model can be applied to cohesive, non-cohesive, or mixed sediments. The sediment transport is simulated using bathymetry data, bed resistance characteristics, wave height and period, depth-averaged current velocity and bed material type, size and gradation, which vary throughout the model domain.The non-cohesive sediment transport model is based on a solution of two-dimensional mass conservation equations for the bed layer material and 2D equations for movement of sediment fractions either bed load or suspended load. The water column and bottom are divided into a set of layers: water layer, active layer, several active bed layers, and the bed layer. The model also takes into account the effects of armoring and changes in the bed composition. Cohesive sediments move entirely as suspended load in the water layer and sediment transport computations are based on a solution of the two-dimensional mass conservation equations for the bed layer material and two-dimensional equations for movement of sediment as suspended load. The water column and bed, as for non-cohesive sediments, was divided into a set of layers. Following the approach of Van Ledden (2002), the erosion of sediments made up of mud and sand mixtures is non-cohesive if the mud content is below a critical level. Above a critical mud content, the bed behaves cohesively. Deposition fluxes of mud and sand are independent. The sediment concentration in the water and active layer is represented by

  19. The Transporter Classification Database

    PubMed Central

    Saier, Milton H.; Reddy, Vamsee S.; Tamang, Dorjee G.; Västermark, Åke

    2014-01-01

    The Transporter Classification Database (TCDB; http://www.tcdb.org) serves as a common reference point for transport protein research. The database contains more than 10 000 non-redundant proteins that represent all currently recognized families of transmembrane molecular transport systems. Proteins in TCDB are organized in a five level hierarchical system, where the first two levels are the class and subclass, the second two are the family and subfamily, and the last one is the transport system. Superfamilies that contain multiple families are included as hyperlinks to the five tier TC hierarchy. TCDB includes proteins from all types of living organisms and is the only transporter classification system that is both universal and recognized by the International Union of Biochemistry and Molecular Biology. It has been expanded by manual curation, contains extensive text descriptions providing structural, functional, mechanistic and evolutionary information, is supported by unique software and is interconnected to many other relevant databases. TCDB is of increasing usefulness to the international scientific community and can serve as a model for the expansion of database technologies. This manuscript describes an update of the database descriptions previously featured in NAR database issues. PMID:24225317

  20. Fluctuating transport in microstructures

    SciTech Connect

    Xie, X.

    1988-01-01

    In this dissertation, we study electronic transport properties of various kinds of quasi-one dimensional (Q1D) systems. The dissertation can be divided into the following categories: (1) Conductance fluctuations and phase coherence in microstructures. We study the conductance fluctuations for three different regimes of electronic transport: ballistic, diffusive and variable-range-hopping (VRH). Various numerical methods are used in the calculations. In the VRH problem, we also examine the possibility of observing the Aharonov-Bohm effect. We develop a technique based on the recursive Kubo formula to study the universal conductance fluctuations in the diffusive regime. Close comparison with relevant experiments is made and good agreement is found. (2) Drude transport properties of quasi-one dimensional systems. In this problem, we calculate the density of states and Drude conductivity for the screened impurity scattering using many body theory. The DOS and conductivity show strong oscillatory behavior as a function of the Fermi-energy. Self-consistency is included in our theory. Good agreement with experiment is found. (3) Transport in quasicrystals. In solving this problem we use the Landauer formula approach. We find that the electrical resistance of a finite 1D Fibonacci-sequence quasicrystal shows strong fluctuations as resonant tunneling occurs through the allowed energy states of the system. Power law localization and self-similarity can be seen in the transport properties. A possible experiment to observe this phenomenon is suggested.

  1. ABC transporters: bacterial exporters.

    PubMed Central

    Fath, M J; Kolter, R

    1993-01-01

    The ABC transporters (also called traffic ATPases) make up a large superfamily of proteins which share a common function and a common ATP-binding domain. ABC transporters are classified into three major groups: bacterial importers (the periplasmic permeases), eukaryotic transporters, and bacterial exporters. We present a comprehensive review of the bacterial ABC exporter group, which currently includes over 40 systems. The bacterial ABC exporter systems are functionally subdivided on the basis of the type of substrate that each translocates. We describe three main groups: protein exporters, peptide exporters, and systems that transport nonprotein substrates. Prototype exporters from each group are described in detail to illustrate our current understanding of this protein family. The prototype systems include the alpha-hemolysin, colicin V, and capsular polysaccharide exporters from Escherichia coli, the protease exporter from Erwinia chrysanthemi, and the glucan exporters from Agrobacterium tumefaciens and Rhizobium meliloti. Phylogenetic analysis of the ATP-binding domains from 29 bacterial ABC exporters indicates that the bacterial ABC exporters can be divided into two primary branches. One branch contains the transport systems where the ATP-binding domain and the membrane-spanning domain are present on the same polypeptide, and the other branch contains the systems where these domains are found on separate polypeptides. Differences in substrate specificity do not correlate with evolutionary relatedness. A complete survey of the known and putative bacterial ABC exporters is included at the end of the review. PMID:8302219

  2. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira; Lei Zhou

    2000-01-30

    This is the second quarterly progress report for Year 2 of the ACTS project. It includes a review of progress made in Flow Loop development and research during the period of time between Oct 1, 2000 and December 31, 2000. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 2: Addition of a foam generation and breaker system), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 7): ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (d) Research project (Task 8): ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (e) Research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (g) Research on instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), and Foam properties while transporting cuttings. (Task 12), (h) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (i) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members. The tasks Completed During This Quarter are Task 7 and Task 8.

  3. The High Cost of Transportation.

    ERIC Educational Resources Information Center

    Rasicot, Julie

    1996-01-01

    Describes how school districts, faced with shrinking resources, have cut costs for student transportation. To combat rising transportation costs, districts have charged fees for student transportation, entered into private contracts, cut transportation services, used alternative fuels, and streamlined bus routes and schedules. (LMI)

  4. The High Cost of Transportation.

    ERIC Educational Resources Information Center

    Rasicot, Julie

    1996-01-01

    Describes how school districts, faced with shrinking resources, have cut costs for student transportation. To combat rising transportation costs, districts have charged fees for student transportation, entered into private contracts, cut transportation services, used alternative fuels, and streamlined bus routes and schedules. (LMI)

  5. Packet transport network in metro

    NASA Astrophysics Data System (ADS)

    Huang, Feng; Yi, Xiaobo; Zhang, Hanzheng; Gong, Ping

    2008-11-01

    IP packet based services such as high speed internet, IP voice and IP video will be widely deployed in telecom network, which make transport network evolution to packet transport network. Characteristics of transport network and requirements of packet transport network are analyzed, T-MPLS/MPLS-TP based PTN technology is given and it will be used in metro (access, aggregation and core) network.

  6. [Heavy metal accumulation during last hundred years and its assessment of potential ecological risk in the coastal wetland of Qi'ao Island, Pearl River Estuary of China].

    PubMed

    Wang, Ai-jun; Ye, Xiang; Li, Tuan-jie; Huang, Cai-bin

    2011-05-01

    The processes of fine sediment transport and deposition can record some relative anthropogenic information in estuarine environments. Grain size analysis of the sediment core collected from coastal wetland of Qi'ao Island in the Pearl River Estuary of China show that the sediment is mainly composed by clayey silt, and the mean grain size, contents of clay and silt increase upward gradually. Chronology analysis show that the sedimentation rate above 59 cm is about 4.15 cm x a(-1), and 0.97 cm x a(-1) beneath 59 cm. Heavy metal analysis indicate that the contents of the each heavy metal increased slowly with a slight intensity of potential ecological risk; however, from 1966 to 1992, the heavy metal contents increased obviously because of the quick social-economy development around the Pearl River Estuary area, and the order of polluting degree of these heavy metals in core sediment is Cd > Ni > Pb > Cu > Cr > Zn. The potential ecological risk intensity of Cd increased from slight risk before 1966 to strong risk since 1992, and the potential ecological risk intensities other heavy metal are slight risk; the potential ecological risk index is weak level. The variations of core sediment heavy metal contents and its ecological risk assessments along the vertical profile reveal the interaction processes and intent of anthropogenic influences from the areas around the Pearl River Estuary and the catchments.

  7. Solute transport in groundwater

    NASA Astrophysics Data System (ADS)

    Dougherty, David E.

    Continued research interest in transport in the subsurface was demonstrated at the “Solute Transport in Groundwater” session held at the 1985 AGU Spring Meeting in Baltimore. This session, following on the heels of the very successful special symposium on “Coupling Geochemical and Hydrologic Models for Subsurface Solute Transport,” was organized by Lenny Konikow of the U.S. Geological Survey (USGS, Reston, Va.) and copresided by Steve Gorelick (USGS, Menlo Park, Calif.) and David Dougherty (Princeton University, Princeton, N.J.). Participation was strong, with 12 contributed papers and about 150 attendees. The papers addressed a wide variety of topics, ranging from the theoretical to the applied, from physics to numerical methods.

  8. Transportation Institutional Plan

    SciTech Connect

    Not Available

    1986-08-01

    This Institutional Plan is divided into three chapters. Chapter 1 provides background information, discusses the purposes of the Plan and the policy guidance for establishing the transportation system, and describes the projected system and the plans for its integrated development. Chapter 2 discusses the major participants who must interact to build the system. Chapter 3 suggests mechanisms for interaction that will foster wide participation in program planning and implementation and provides a framework for managing and resolving the issues related to development and operation of the transportation system. A list of acronyms and a glossary are included for the reader's convenience. Also included in this Plan are four appendices. Of particular importance is Appendix A, which includes detailed discussion of specific transportation issues. Appendices B, C, and D provide supporting material to assist the reader in understanding the roles of the involved institutions.

  9. Prioritized Contact Transport Stream

    NASA Technical Reports Server (NTRS)

    Hunt, Walter Lee, Jr. (Inventor)

    2015-01-01

    A detection process, contact recognition process, classification process, and identification process are applied to raw sensor data to produce an identified contact record set containing one or more identified contact records. A prioritization process is applied to the identified contact record set to assign a contact priority to each contact record in the identified contact record set. Data are removed from the contact records in the identified contact record set based on the contact priorities assigned to those contact records. A first contact stream is produced from the resulting contact records. The first contact stream is streamed in a contact transport stream. The contact transport stream may include and stream additional contact streams. The contact transport stream may be varied dynamically over time based on parameters such as available bandwidth, contact priority, presence/absence of contacts, system state, and configuration parameters.

  10. Transportable hyperpolarized metabolites

    NASA Astrophysics Data System (ADS)

    Ji, Xiao; Bornet, Aurélien; Vuichoud, Basile; Milani, Jonas; Gajan, David; Rossini, Aaron J.; Emsley, Lyndon; Bodenhausen, Geoffrey; Jannin, Sami

    2017-01-01

    Nuclear spin hyperpolarization of 13C-labelled metabolites by dissolution dynamic nuclear polarization can enhance the NMR signals of metabolites by several orders of magnitude, which has enabled in vivo metabolic imaging by MRI. However, because of the short lifetime of the hyperpolarized magnetization (typically <1 min), the polarization process must be carried out close to the point of use. Here we introduce a concept that markedly extends hyperpolarization lifetimes and enables the transportation of hyperpolarized metabolites. The hyperpolarized sample can thus be removed from the polarizer and stored or transported for use at remote MRI or NMR sites. We show that hyperpolarization in alanine and glycine survives 16 h storage and transport, maintaining overall polarization enhancements of up to three orders of magnitude.

  11. Preface: Nonclassical Transport

    SciTech Connect

    Bolshov, L.; Kondratenko, P.; Pruess, K.

    2008-09-01

    Transport phenomena in highly heterogeneous media can be dramatically different from those in homogeneous media and therefore are of great fundamental and practical interest. Anomalous transport occurs in semiconductor physics, plasma physics, astrophysics, biology, and other areas. It plays an especially important role in hydrogeology because it may govern the rate of migration and degree of dispersion of groundwater contaminants from hazardous waste sites. The series of four articles in this special section of Vadose Zone Journal is devoted to transport phenomena in heterogeneous media in the context of geologic disposal of radioactive waste. It contains the results of joint investigations performed at the Nuclear Safety Institute of the Russian Academy of Sciences and Lawrence Berkeley National Laboratory in California. The work was supported by the U.S. DOE (under Contract No. DEAC02-05CH11231). The problems addressed in this research involve a broad range of space and time scales and were approached using modern methods of theoretical and computational physics, such as scaling analysis and diagrammatic techniques used before in critical phenomena theory. Special attention is paid to the asymptotics of concentration behavior (concentration tails). This issue is exceptionally important for the reliability assessments of radioactive waste disposal because, depending on the structure of the tails, concentrations at large distances from the source can differ by many orders of magnitude. In the first paper of this special section, Bolshov et al. (2008b) present an overview of field and laboratory observations that demonstrate nonclassical flow and transport behavior in geologic media. It is recognized that natural fracture networks as a rule have fractal geometry and can be classified as percolation systems. This is one of the main factors giving rise to anomalous transport in geologic media. Another important factor is the presence of contaminant traps provided by

  12. Intermodal Transportation, USACE Style

    SciTech Connect

    Grumski, K. M.; Coutts, P. W.

    2002-02-27

    The US Army Corps of Engineers (USACE) has developed project management techniques with a proven track record for safe and successful results for constructing large scale and massive projects such as improving our nations water transportation systems, flood control, bridges and dams. Applying many of these techniques to the Formerly Utilized Sites Remedial Action Program (FUSRAP) managed by USACE to remediate the environment is achieving the same safe and successful results as their construction projects. This paper examines the additional economics and improved safety results of using intermodal containers and a combination of rail and truck transportation conveyances to transport the contaminated soil and debris from the Linde FUSRAP site, located in Tonawanda, New York.

  13. Transportable hyperpolarized metabolites

    PubMed Central

    Ji, Xiao; Bornet, Aurélien; Vuichoud, Basile; Milani, Jonas; Gajan, David; Rossini, Aaron J.; Emsley, Lyndon; Bodenhausen, Geoffrey; Jannin, Sami

    2017-01-01

    Nuclear spin hyperpolarization of 13C-labelled metabolites by dissolution dynamic nuclear polarization can enhance the NMR signals of metabolites by several orders of magnitude, which has enabled in vivo metabolic imaging by MRI. However, because of the short lifetime of the hyperpolarized magnetization (typically <1 min), the polarization process must be carried out close to the point of use. Here we introduce a concept that markedly extends hyperpolarization lifetimes and enables the transportation of hyperpolarized metabolites. The hyperpolarized sample can thus be removed from the polarizer and stored or transported for use at remote MRI or NMR sites. We show that hyperpolarization in alanine and glycine survives 16 h storage and transport, maintaining overall polarization enhancements of up to three orders of magnitude. PMID:28072398

  14. Lunar material transport vehicle

    NASA Technical Reports Server (NTRS)

    Fisher, Charles D.; Lyons, Douglas; Wilkins, W. Allen, Jr.; Whitehead, Harry C., Jr.

    1988-01-01

    The proposed vehicle, the Lunar Material Transport Vehicle (LMTV), has a mission objective of efficient lunar soil material transport. The LMTV was designed to meet a required set of performance specifications while operating under a given set of constraints. The LMTV is essentially an articulated steering, double-ended dump truck. The vehicle moves on four wheels and has two identical chassis halves. Each half consists of a chassis frame, a material bucket, two wheels with integral curvilinear synchronous motors, a fuel cell and battery arrangement, an electromechanically actuated dumping mechanism, and a powerful microprocessor. The vehicle, as designed, is capable of transporting up to 200 cu ft of material over a one mile round trip per hour. The LMTV is capable of being operated from a variety of sources. The vehicle has been designed as simply as possible with attention also given to secondary usage of components.

  15. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Ergun Kuru; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Len Volk; Mark Pickell; Evren Ozbayoglu; Barkim Demirdal; Paco Vieira; Affonso Lourenco

    1999-10-15

    This report includes a review of the progress made in ACTF Flow Loop development and research during 90 days pre-award period (May 15-July 14, 1999) and the following three months after the project approval date (July15-October 15, 1999) The report presents information on the following specific subjects; (a) Progress in Advanced Cuttings Transport Facility design and development, (b) Progress report on the research project ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (c) Progress report on the research project ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (d) Progress report on the research project ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (e) Progress report on the research project ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Progress report on the instrumentation tasks (Tasks 11 and 12) (g) Activities towards technology transfer and developing contacts with oil and service company members.

  16. Nitrate transport and signalling.

    PubMed

    Miller, Anthony J; Fan, Xiaorong; Orsel, Mathilde; Smith, Susan J; Wells, Darren M

    2007-01-01

    Physiological measurements of nitrate (NO(3)(-)) uptake by roots have defined two systems of high and low affinity uptake. In Arabidopsis, genes encoding both of these two uptake systems have been identified. Most is known about the high affinity transport system (HATS) and its regulation and yet measurements of soil NO(3)(-) show that it is more often available in the low affinity range above 1 mM concentration. Several different regulatory mechanisms have been identified for AtNRT2.1, one of the membrane transporters encoding HATS; these include feedback regulation of expression, a second component protein requirement for membrane targeting and phosphorylation, possibly leading to degradation of the protein. These various changes in the protein may be important for a second function in sensing NO(3)(-) availability at the surface of the root. Another transporter protein, AtNRT1.1 also has a role in NO(3)(-) sensing that, like AtNRT2.1, is independent of their transport function. From the range of concentrations present in the soil it is proposed that the NO(3)(-)-inducible part of HATS functions chiefly as a sensor for root NO(3)(-) availability. Two other key NO(3)(-) transport steps for efficient nitrogen use by crops, efflux across membranes and vacuolar storage and remobilization, are discussed. Genes encoding vacuolar transporters have been isolated and these are important for manipulating storage pools in crops, but the efflux system is yet to be identified. Consideration is given to how well our molecular and physiological knowledge can be integrated as well to some key questions and opportunities for the future.

  17. The Trojan. [supersonic transport

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The Trojan is the culmination of thousands of engineering person-hours by the Cones of Silence Design Team. The goal was to design an economically and technologically viable supersonic transport. The Trojan is the embodiment of the latest engineering tools and technology necessary for such an advanced aircraft. The efficient design of the Trojan allows for supersonic cruise of Mach 2.0 for 5,200 nautical miles, carrying 250 passengers. The per aircraft price is placed at $200 million, making the Trojan a very realistic solution for tomorrows transportation needs. The following is a detailed study of the driving factors that determined the Trojan's super design.

  18. FAA Smoke Transport Code

    SciTech Connect

    Domino, Stefan; Luketa-Hanlin, Anay; Gallegos, Carlos

    2006-10-27

    FAA Smoke Transport Code, a physics-based Computational Fluid Dynamics tool, which couples heat, mass, and momentum transfer, has been developed to provide information on smoke transport in cargo compartments with various geometries and flight conditions. The software package contains a graphical user interface for specification of geometry and boundary conditions, analysis module for solving the governing equations, and a post-processing tool. The current code was produced by making substantial improvements and additions to a code obtained from a university. The original code was able to compute steady, uniform, isothermal turbulent pressurization. In addition, a preprocessor and postprocessor were added to arrive at the current software package.

  19. Mars surface transportation options

    NASA Technical Reports Server (NTRS)

    Leitner, Jeffrey M.; Alred, John W.

    1986-01-01

    As the number of scientific experiments for the surface of Mars grows, the need for effective surface transportation becomes critical. Because of the diversity of the experiments proposed, as well as the desire to explore Mars from the equator to the poles, the optimum surface vehicle configuration is not obvious. Five candidate vehicles are described, with an estimate of their size and performance. In order to maximize the success of a manned Mars mission, it appears that two vehicles should be designed for surface transportation: an advanced long-range rover, and a remotely-piloted airplane.

  20. Transport of cholesterol.

    PubMed

    Norum, K R; Berg, T; Helgerud, P; Drevon, C A

    1983-10-01

    .ur current model for cholesterol transport is summarized in Figure 10. In this figure we have put together the various steps in cholesterol transport that were described previously in this review. Under normal conditions, cholesterol metabolism and transport are well regulated. If the transport system is overloaded for a long time, however, hypercholesterolemia caused mainly by increased plasma LDL may develop in several species, including humans. Under such circumstances reverse transport of cholesterol may also fail, giving rise to deposits of cholesterol. Tissue macrophages may be responsible for this lipid accumulation, because receptor-mediated (adsorptive) endocytosis of lipoprotein-associated cholesterol in these cells is not under negative-feedback control. The deposits are mainly found in tissues poorly supplied with blood and lymph: the skin, tendons, the cornea, and arteries. Overload of cholesterol transport may be the result of too much fat and cholesterol in the diet, giving rise to cholesterol-rich lipoproteins from the gut and to increased production of liver (formula; see text) VLDL, which in humans ends up as LDL. In many individuals, however, no hypercholesterolemia is seen, even after eating large amounts of a "western" diet for decades; others may develop increased LDL on a relatively "prudent" diet. Obviously many of the factors and mechanisms in cholesterol transport are influenced by genetic factors. Although studies of several inborn errors of lipid metabolism have given information about some mechanisms, the quantitatively more important differences in genetic patterns, which determine whether or not a western diet will result in hyperlipidemia, are not well known. Perhaps studies of different forms of apoB and apoE and of HDL subgroups and hyper-alpha-lipoproteinemia will explain why certain individuals develop hypercholesterolemia and premature atherosclerosis. All the recent information related to cholesterol metabolism and transport

  1. Mobile transporter path planning

    NASA Technical Reports Server (NTRS)

    Baffes, Paul; Wang, Lui

    1990-01-01

    The use of a genetic algorithm (GA) for solving the mobile transporter path planning problem is investigated. The mobile transporter is a traveling robotic vehicle proposed for the space station which must be able to reach any point of the structure autonomously. Elements of the genetic algorithm are explored in both a theoretical and experimental sense. Specifically, double crossover, greedy crossover, and tournament selection techniques are examined. Additionally, the use of local optimization techniques working in concert with the GA are also explored. Recent developments in genetic algorithm theory are shown to be particularly effective in a path planning problem domain, though problem areas can be cited which require more research.

  2. Railway switch transport model.

    PubMed

    Horvat, Martin; Prosen, Tomaž; Benenti, Giuliano; Casati, Giulio

    2012-11-01

    We propose a simple model of coupled heat and particle transport based on zero-dimensional classical deterministic dynamics, which is reminiscent of a railway switch whose action is a function only of the particle's energy. It is shown that already in the minimal three-terminal model, where the second terminal is considered as a probe with zero net particle and heat currents, one can find extremely asymmetric Onsager matrices as a consequence of time-reversal symmetry breaking of the model. This minimalistic transport model provides a better understanding of thermoelectric heat engines in the presence of time-reversal symmetry breaking.

  3. National Transportable Telecommunications Capability

    NASA Astrophysics Data System (ADS)

    Boheim, Kenneth B.; Dayton, Allen D.

    The National Communications System (NCS) in its role of planning for emergency telecommunications restoration has contracted for a deployable asset to be available for National Security and Emergency Preparedness (NS/EP) uses. This asset, the National Transportable Telecommunications Capability (NTTC) is a transportable package consisting of a cellular switch and base station in a shelter, a microwave radio system, a small telephone switch, and a mobile satellite terminal. This package will operate over a Ku-band domestic satellite back into a gateway station and into the packet switching network. A description of the system is provided, an overview of deployment issues is given, and potential enhancements are presented.

  4. Transformation of transportation. [Monograph

    SciTech Connect

    Not Available

    1981-01-01

    Rising energy and resource costs can be seen as an opportunity to redefine our transportation vehicles and networks, a chance to explore the potential of neighborhood-scaled systems involving bikes, footpaths, small buses and taxis as well as intercity trains and dirigibles that efficiently cover the distance while simultaneously providing a convivial experience of mobility. It is also a time to redefine the automobile and seek its ideal use. This approach is applied to transportation in California, its history and projected future. 11 references, 11 figures.

  5. Atomic transport of oxygen

    SciTech Connect

    Routbort, J.L.; Tomlins, G.W.

    1994-06-15

    Atomic transport of oxygen in nonstoichiometric oxides is an extremely important topic which overlaps science and technology. In many cases the diffusion of oxygen controls sintering, grain growth, and creep. High oxygen diffusivity is critical for efficient operation of many fuel cells. Additionally, oxygen diffusivities are an essential ingredient in any point defect model. Secondary Ion Mass Spectrometry (SIMS) is the most accurate modern technique to measure oxygen tracer diffusion. This paper briefly reviews the principles and applications of SIMS for the measurement of oxygen transport. Case studies are taken from recent work on ZnO and some high-temperature superconductors.

  6. Transport Aircraft Accident Dynamics

    DTIC Science & Technology

    1982-03-01

    SA Contracti’ Report 165850 S,">.AA 11’ýport No. VL)T-FAR-CT-8Z-T0 i0 u; S𔃺/3!D35" *. T -ansport Aircraft Accident Dynamics Reproduced From Srt...City, New Jersey 08405 84 04-. , NASA Contractor Report FAA Report No. Dbr-MA -C7 ,-70 TRANSPORT AIRCRAFT. ACCIDENT DYNAMICS I A. COMINSKY, et al...transport aircraft accidents , the association between structural systems and accident injuries and the identification of typical scenarios. This report

  7. Introduction to radiation transport

    SciTech Connect

    Olson, G.L.

    1998-12-31

    This lecture will present time-dependent radiation transport where the radiation is coupled to a static medium, i.e., the material is not in motion. In reality, radiation exerts a pressure on the materials it propagates through and will accelerate the material in the direction of the radiation flow. This fully coupled problem with radiation transport and materials in motion is referred to as radiation-hydrodynamics (or in a shorthand notation: rad-hydro) and is beyond the scope of this lecture.

  8. Smart vehicular transportation systems

    SciTech Connect

    Little, C.Q.; Wilson, C.W.

    1997-05-01

    This work builds upon established Sandia intelligent systems technology to develop a unique approach for the integration of intelligent system control into the US Highway and urban transportation systems. The Sandia developed concept of the COPILOT controller integrates a human driver with computer control to increase human performance while reducing reliance on detailed driver attention. This research extends Sandia expertise in sensor based, real-time control of robotics systems to high speed transportation systems. Knowledge in the form of maps and performance characteristics of vehicles provides the automatic decision making intelligence needed to plan optimum routes, maintain safe driving speeds and distances, avoid collisions, and conserve fuel.

  9. LDEF (Flight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Flight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 EL-1994-00666 LDEF (Flight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 The flight photograph was taken from the Orbiter aft flight deck during the LDEF retrieval prior to berthing the LDEF in the Orbiter cargo bay and shows the Solar Array Materials Passive LDEF Experiment (SAMPLE) on the LDEF. Six (6) plates of passive components, provided by various experiment organizations and designated plate I thru plate VI, are shown mounted in a three (3) inch deep LDEF peripheral tray. All six plates are aluminum and attach to the LDEF experiment tray with non-magnetic stainless steel fasteners. Plate I, located in the upper left corner, consist of a combination of solar cells with and without covers, solar cell modules and solar arrays assembled on the baseplate. Two of the four solar arrays are missing and one appears to be attached at only one corner. Other components appear to be secure. Plate II in the left center section, has twenty-seven (27) composite samples, carbon fiber and glass fiber, mounted on the baseplate. The composites appear to be intact with no physical damage. Plate III, in the lower left corner, consist mostly of metallized and thin polymeric films (Kapton, Mylar, TEFLON® , white Tedlar,etc.). The thin films without protective coatings sustained significant damage and most were destroyed. The metallized film apparently survived with minimum damage. Plate IV located in the upper right corner consist of metals and coatings mounted in an aluminum baseplate and covered with a thin aluminum coverplate that partially mask the specimen. Several of the coatings appear to have changed to a darker color and a light brown discoloration appears around the outer edges of the mounting plate and along the right edge of the coverplates. Plate V, in the right center section, contained thermal plastics and structural film configured into tensile and shear specimen. All

  10. LDEF (Postflight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Postflight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 EL-1994-00147 LDEF (Postflight), AO171 : Solar-Array-Materials Passive LDEF Experiment, Tray A08 The post flight photograph was taken in the SAEF II at KSC prior to removal of the experiment tray from the LDEF and shows the Solar Array Materials Passive LDEF Experiment (SAMPLE) on the LDEF. Six (6) plates of passive components, provided by various experiment organizations and designated plate I thru plate VI, are shown mounted in a three (3) inch deep LDEF peripheral tray. All six plates are aluminum and attach to the LDEF experiment tray with non-magnetic stainless steel fasteners. Plate I, located in the upper right corner, consist of a combination of solar cells with and without covers, solar cell modules and solar arrays assembled on the baseplate. Three of the four solar arrays are missing. Other components appear to be secure. Plate II in the top center section, has twenty seven (27) composite samples, carbon fiber and glass fiber, mounted on the baseplate. The composites appear to be intact with no physical damage. Plate III, in the upper left corner, consist of metallized and thin polymeric films (Kapton, Mylar, TEFLON® , white Tedlar,etc.). The thin films without protective coatings sustained significant damage and most were destroyed. The thin film specimen hanging by one end in the flight photograph is missing. The metallized film apparently survived the mission with minimum damage. Plate IV located in the lower right corner consist of metals and coatings mounted in an aluminum baseplate and covered with a thin aluminum coverplate that partially mask the specimen. Several of the coatings appear to have darkened and a unique pattern of light brown discoloration appears around the outer edges of the mounting plate and along the lower edge of the coverplates. Plate V, in the lower center section, contained thermal plastics and structural film configured into tensile and

  11. Transportation and platforms perspective

    NASA Technical Reports Server (NTRS)

    Bennett, Gary L.

    1992-01-01

    The topics covered are presented in viewgraph form and include the following: Office of Aeronautics and Space Technology; space research and technology (R&T); space R&T mission statement; Space R&T program development; R&T strategy; Office of Space Science and Applications (OSSA) technology needs; transportation technology; and space platforms technology.

  12. EPAct Transportation Regulatory Activities

    SciTech Connect

    2011-11-21

    The U.S. Department of Energy's (DOE) Vehicle Technologies Program manages several transportation regulatory activities established by the Energy Policy Act of 1992 (EPAct), as amended by the Energy Conservation Reauthorization Act of 1998, EPAct 2005, and the Energy Independence and Security Act of 2007 (EISA).

  13. Technology transfer-transportation

    NASA Technical Reports Server (NTRS)

    Anyos, T.; Lizak, R.; Wilhelm, J.

    1974-01-01

    Problems in the public transportation industry and refining methods for decreasing the time gap between the development and the marketing of new technology are considered. Eight NASA innovations are either being adapted for use on highways, railways, or rapid transit, or are already entering the marketplace. Chronologies for three of these programs are provided.

  14. High speed civil transport

    NASA Technical Reports Server (NTRS)

    1991-01-01

    This report discusses the design and marketability of a next generation supersonic transport. Apogee Aeronautics Corporation has designated its High Speed Civil Transport (HSCT): Supercruiser HS-8. Since the beginning of the Concorde era, the general consensus has been that the proper time for the introduction of a next generation Supersonic Transport (SST) would depend upon the technical advances made in the areas of propulsion (reduction in emissions) and material composites (stronger, lighter materials). It is believed by many in the aerospace industry that these beforementioned technical advances lie on the horizon. With this being the case, this is the proper time to begin the design phase for the next generation HSCT. The design objective for a HSCT was to develop an aircraft that would be capable of transporting at least 250 passengers with baggage at a distance of 5500 nmi. The supersonic Mach number is currently unspecified. In addition, the design had to be marketable, cost effective, and certifiable. To achieve this goal, technical advances in the current SST's must be made, especially in the areas of aerodynamics and propulsion. As a result of these required aerodynamic advances, several different supersonic design concepts were reviewed.

  15. Nearshore Sand Transport.

    DTIC Science & Technology

    1987-01-01

    Born November 19, 1956 - Peoria, Illinois 1978 B.S., Civil Engineering, University of Miami, Coral Gables, Florida 1978 B.S., Physics, University of...Aubrey, 1985, "Theoretical and observational estimates of nearshore bedload transport rates," Marino Geology, v 64, p 91-111. Guza, R.T., N.C. Clifton

  16. Draft Transportation Institutional Plan

    SciTech Connect

    Not Available

    1985-09-01

    The Department of Energy recognizes that the success of its program to develop and implement a national system for nuclear waste management and disposal depends on broad-based public understanding and acceptance. While each program element has its particular sensitivity, the transportation of the waste may potentially affect the greatest number of people, and accordingly is highly visible and potentially issue-laden. Therefore, the Office of Civilian Radioactive Waste Management has developed this Transportation Institutional Plan to lay the foundation for interaction among all interested parties for the purpose of identifying and resolving issues of concern. The Plan is divided into four chapters. Chapter 1 provides bachground information and discusses the purpose of the Plan and the policy guidance for establishing the transportation system. Chapter 2 introduces the major participants who must interact to build both the system itself and the consensus philosophy that is essential for effective operations. Chapter 3 suggests mechanisms for interaction that will ensure wide participation in program planning and implementation. And, finally, Chapter 4 suggests a framework for managing and resolving the issues related to development and operation of the transportation system. A list of acronyms and a glossary are included for the reader's convenience. The Plan's appendices provide supporting material to assist the reader in understanding the roles of the involved institutions. 4 figs., 1 tab.

  17. Charging up Transportation.

    ERIC Educational Resources Information Center

    Vail, Kathleen R.

    1994-01-01

    In Antelope Valley, California, a regional transportation consortium, cooperatively run by six adjacent school districts, is operating an electric-powered school bus as a pilot project. Although the prototype bus cost nearly six times more than a traditional school bus, lower operating and maintenance expenses and safety factors appeal to many…

  18. Phloem transport in trees

    Treesearch

    Michael G. Ryan; Shinichi. Asao

    2014-01-01

    Phloem is like an enigmatic central banker: we know how important phloem is to plant function, but very little about how phloem functions as part of a whole-plant economy. Phloem transports carbohydrates, produced by photosynthesis and hydrolysis of reserve compounds, to sink tissues for growth, respiration and storage. At photosynthetic tissues, carbohydrates are...

  19. A lunar transportation system

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Due to large amounts of oxygen required for space travel, a method of mining, transporting, and storing this oxygen in space would facilitate further space exploration. The following project deals specifically with the methods for transporting liquid oxygen from the lunar surface to the Lunar Orbit (LO) space station, and then to the Lower Earth Orbit (LEO) space station. Two vehicles were designed for operation between the LEO and LO space stations. The first of these vehicles is an aerobraked design vehicle. The Aerobrake Orbital Transfer Vehicle (OTV) is capable of transporting 5000 lbm of payload to LO while returning to LEO with 60,000 lbm of liquid oxygen, and thus meet mission requirements. The second vehicle can deliver 18,000 lbm of payload to LO and is capable of bringing 60,000 lbm of liquid oxygen back to LEO. A lunar landing vehicle was also designed for operation between LO and the established moon base. The use of an electromagnetic railgun as a method for launching the lunar lander was also investigated. The feasibility of the railgun is doubtful at this time. A system of spheres was also designed for proper storing and transporting of the liquid oxygen. The system assumes a safe means for transferring the liquid oxygen from tank to tank is operational. A sophisticated life support system was developed for both the OTV and the lunar lander. This system focuses on such factors as the vehicle environment, waste management, water requirements, food requirements, and oxygen requirements.

  20. Charging up Transportation.

    ERIC Educational Resources Information Center

    Vail, Kathleen R.

    1994-01-01

    In Antelope Valley, California, a regional transportation consortium, cooperatively run by six adjacent school districts, is operating an electric-powered school bus as a pilot project. Although the prototype bus cost nearly six times more than a traditional school bus, lower operating and maintenance expenses and safety factors appeal to many…

  1. Urban Mass Transportation.

    ERIC Educational Resources Information Center

    Mervine, K. E.

    This bibliography is part of a series of Environmental Resource Packets prepared under a grant from EXXON Education Foundation. The most authoritative and accessible references in the urban transportation field are reviewed. The authors, publisher, point of view, level, and summary are given for each reference. The references are categorized…

  2. Cutting Transportation Costs.

    ERIC Educational Resources Information Center

    Lewis, Barbara

    1982-01-01

    Beginning on the front cover, this article tells how school districts are reducing their transportation costs. Particularly effective measures include the use of computers for bus maintenance and scheduling, school board ownership of buses, and the conversion of gasoline-powered buses to alternative fuels. (Author/MLF)

  3. Storing and transporting energy

    DOEpatents

    McClaine, Andrew W.; Brown, Kenneth

    2010-09-07

    Among other things, hydrogen is released from water at a first location using energy from a first energy source; the released hydrogen is stored in a metal hydride slurry; and the metal hydride slurry is transported to a second location remote from the first location.

  4. Metrics for Transportation.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of students interested in transportation, this instructional package is one of five for the marketing and distribution cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational terminology,…

  5. Alternate Transportation Routes

    ERIC Educational Resources Information Center

    Vogel, Carl

    2009-01-01

    Since last school year, the St. Lucie County (Florida) Public Schools reduced the number of buses it operates from 399 to 362, despite opening two new schools. Add in some other smart changes in policy, and the district lowered its annual transportation costs by more than $3 million over last year. Saving $3 million a year does not come easily,…

  6. Cutting Transportation Costs.

    ERIC Educational Resources Information Center

    Lewis, Barbara

    1982-01-01

    Beginning on the front cover, this article tells how school districts are reducing their transportation costs. Particularly effective measures include the use of computers for bus maintenance and scheduling, school board ownership of buses, and the conversion of gasoline-powered buses to alternative fuels. (Author/MLF)

  7. Urban Mass Transportation.

    ERIC Educational Resources Information Center

    Mervine, K. E.

    This bibliography is part of a series of Environmental Resource Packets prepared under a grant from EXXON Education Foundation. The most authoritative and accessible references in the urban transportation field are reviewed. The authors, publisher, point of view, level, and summary are given for each reference. The references are categorized…

  8. Reactive transport modeling

    USDA-ARS?s Scientific Manuscript database

    This special section in the Vadose Zone Journal focusing on reactive transport modeling was developed from a special symposium jointly sponsored by the Soil Physics and Soil Chemistry Divisions of the Soil Science Society of America at the 2010 annual meetings held in Long Beach, CA. It contains eig...

  9. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington

    2003-01-30

    This is the second quarterly progress report for Year-4 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between October 1, 2002 and December 30, 2002. This report presents a review of progress on the following specific tasks. (a) Design and development of an Advanced Cuttings Transport Facility Task 3: Addition of a Cuttings Injection/Separation System, Task 4: Addition of a Pipe Rotation System. (b) New research project (Task 9b): ''Development of a Foam Generator/Viscometer for Elevated Pressure and Elevated Temperature (EPET) Conditions''. (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions''. (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b). (f) New Research project (Task 13): ''Study of Cuttings Transport with Foam under Elevated Pressure and Temperature Conditions''. (g) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (h) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  10. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Affonso Lourenco; Evren Ozbayoglu; Lei Zhou

    2002-01-30

    This is the second quarterly progress report for Year 3 of the ACTS project. It includes a review of progress made in: (1) Flow Loop development and (2) research tasks during the period of time between Oct 1, 2001 and Dec. 31, 2001. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 3: Addition of a Cuttings Injection/Collection System), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (e) Research on instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), and Foam properties while transporting cuttings. (Task 12), (f) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  11. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira

    2000-10-30

    This is the first quarterly progress report for Year 2 of the ACTS project. It includes a review of progress made in Flow Loop development and research during the period of time between July 14, 2000 and September 30, 2000. This report presents information on the following specific tasks: (a) Progress in Advanced Cuttings Transport Facility design and development (Task 2), (b) Progress on research project (Task 8): ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (c) Progress on research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (d) Progress on research project (Task 7): ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (e) Progress on research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Initiate research on project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (g) Progress on instrumentation tasks to measure: Cuttings concentration and distribution (Tasks 11), and Foam properties (Task 12), (h) Initiate a comprehensive safety review of all flow-loop components and operational procedures. Since the previous Task 1 has been completed, we will now designate this new task as: (Task 1S). (i) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  12. Hyperbolic type transport equations

    NASA Astrophysics Data System (ADS)

    García-Colín, L. S.; Olivares-Robles, M. A.

    1995-02-01

    In recent years hyperbolic type transport equations have acquired a great deal of importance in problems ranging from theoretical physics to biology. In spite of their greater mathematical difficulty as compared with their parabolic type analogs arising from the framework of Linear Irreversible Thermodynamics, they have, in many ways, superseded the latter ones. Although the use of this type of equations is well known since the last century through the telegraphist equation of electromagnetic theory, their use in studying several problems in transport theory is hardly fifty years old. In fact the first appearance of a hyperbolic type transport equation for the problem of heat conduction dates back to Cattaneos' work in 1948. Three years later, in 1951 S. Goldstein showed how in the theory of stochastic processes this type of an equation is obtained in the continuous limit of a one-dimensional persistent random walk problem. After that, other phenomenological derivations have been offered for such equations. The main purpose of this paper is to critically discuss a derivation of a hyperbolic type Fokker-Planck equation recently presented using the same ideas as M.S. Green did in 1952 to provide the stochastic foundations of irreversible statistical mechanics. Arguments are given to show that such an equation as well as transport equations derived from it by taking appropriate averages are at most approximate and that a much more detailed analysis is required before asserting their validity.

  13. Space station mobile transporter

    NASA Technical Reports Server (NTRS)

    Renshall, James; Marks, Geoff W.; Young, Grant L.

    1988-01-01

    The first quarter of the next century will see an operational space station that will provide a permanently manned base for satellite servicing, multiple strategic scientific and commercial payload deployment, and Orbital Maneuvering Vehicle/Orbital Transfer Vehicle (OMV/OTV) retrieval replenishment and deployment. The space station, as conceived, is constructed in orbit and will be maintained in orbit. The construction, servicing, maintenance and deployment tasks, when coupled with the size of the station, dictate that some form of transportation and manipulation device be conceived. The Transporter described will work in conjunction with the Orbiter and an Assembly Work Platform (AWP) to construct the Work Station. The Transporter will also work in conjunction with the Mobile Remote Servicer to service and install payloads, retrieve, service and deploy satellites, and service and maintain the station itself. The Transporter involved in station construction when mounted on the AWP and later supporting a maintenance or inspection task with the Mobile Remote Servicer and the Flight Telerobotic Servicer is shown.

  14. Transportation: Destination Mars

    NASA Technical Reports Server (NTRS)

    Eoff, Bill

    1998-01-01

    As the agency space transportation lead center, Marshall Space Flight Center has been conducting transportation assessments for future robotic and human Mars missions to identify critical technologies. Five human Mars options are currently under assessment with each option including all transportation requirements from Earth to Mars and return. The primary difference for each option is the propulsion source from Earth to Mars. In case any of the options require heavy launch capability that is not currently projected as available, an in-house study has been initiated to determine the most cost effective means of providing such launch capability. This assessment is only considering launch architectures that support the overall human Mars mission cost goal of $25B. The guidelines for the launch capability study included delivery of 80 metric ton (176 KLB) payloads, 25 feet diameter x 92 feet long, to 220 nmi orbits at 28.5 degrees. The launch vehicle concept of the study was designated "Magnum" to differentiate from prior heavy launch vehicle assessments. This assessment along with the assessment of options for all transportation phases of a Mars mission are on-going.

  15. Safe transport of cyanamide.

    PubMed

    Wehrstedt, Klaus-Dieter; Wildner, Werner; Güthner, Thomas; Holzrichter, Klaus; Mertschenk, Bernd; Ulrich, Armin

    2009-10-30

    For many years cyanamide (CAS no. 420-04-2) was not commercially available due to its unstable nature. Since about 1965 the former "Süddeutsche Kalkstickstoffwerke AG" (current name: AlzChem Trostberg GmbH) developed a special stabilizing system. It was to be investigated to which Class (e.g. "Corrosive Substances", Class 8) or Division (e.g. "Self-reactive Substances", Division 4.1) of the International Regulations for the Transport of Dangerous Goods cyanamide (pure or as a 50% solution in water) should be assigned and based on this which maximum quantities are allowed to transport e.g. in tanks. Cyanamide is used for the synthesis of pharmaceutical and agrochemical actives, biocides, dyestuffs and fine chemicals. During the last years cyanamide was tested at BAM and AQura. The results and an appraisal are presented in this paper. Thus, cyanamide should be classified according to the UN Recommendations on the Transport of Dangerous Goods in Class 8, UN number 2922 (50% solution in water) and UN number 2923 (pure substance) respectively, packaging group III, danger labels 8+6.1. Cyanamide, 50% solution in water, can be transported in portable tanks under specific conditions.

  16. Neoclassical transport in stellarators

    SciTech Connect

    Ho, D.D.M.; Kulsrud, R.M.

    1985-09-01

    The stellarator neoclassical transport due to particles trapped in local helical wells is calculated in the low-collisionality regime using a systematic expansion. The behavior of electron transport is found to be the same over a wide range of energies, but the behavior of ion transport for low energy ions is found to be different than that for high energy ions. Furthermore, the electron fluxes do not vary with the change in the radial ambipolar electric field nearly as much as do the ion fluxes. Thus, the particle diffusion is controlled by the electrons. A nonradial ambipolar electric field is induced by ion drift. This electric field enhances the transport by about 15 to 20%. A convenient graphical method that allows one to determine the magnitude of the radial ambipolar field for machines with different parameters is presented. Numerical examples show that electron energy confinement time is comparable to the ion energy confinement time for all the different size stellarators studied. Although the neoclassical losses are large, it is shown that ignition can be achieved in a reasonably sized stellarator reactor. Finally, from the standpoint of reactor economics, the confinement scaling law shows that in order to increase n tau, it is better to increase the aspect ratio than the overall dimensions of the reactor.

  17. Technology transfer-transportation

    NASA Technical Reports Server (NTRS)

    Anyos, T.; Lizak, R.; Wilhelm, J.; Hirschberg, K.

    1974-01-01

    The application of aerospace technology to the solution of urban public transportation problems is considered. Data are given on highway and railway systems with particular attention given to safety devices, fuel economy, and measures for profiling railways and highways. The development of streamlined truck bodies, to reduce air drag, and efficient brake systems for light trucks and other vehicles was also dealt with.

  18. Stratospheric Transport Modelling

    NASA Astrophysics Data System (ADS)

    Simon, P.

    The MOCAGE chemistry-transport model (CTM) is a new model that has been de- veloped by Météo-France for the study of atmospheric chemistry. The standard ver- sion of the model uses a Semi-Lagrangian (SL) transport scheme, but other numerical schemes (Prather, PPM, etc) can also be activated. It is well known that the main strength of a SL transport scheme is its computational efficiency due to the possible use of large time-steps even for high resolutions; on the other hand, this scheme has two major deficiencies, namely its relatively strong diffusivity and its bad conservation properties. In this study, we shall investigate the impact of the numerics of the model's transport on a seasonal simulation of the stratospheric chemistry. Results from a se- ries of sensitivity experiments will be presented, addressing the following aspects: (1) comparison between the SL scheme and the other schemes (2) how to improve the performance of the SL scheme ? (3) impact of the model's geometry (isobaric vs isentropic levels)

  19. Training Guide: Road Transport.

    ERIC Educational Resources Information Center

    Kogan Page, Ltd., London (England).

    The third in a series of guides to British industrial training, this publication begins with a survey of training issues and tasks confronting the Road Transport Industry Training Board (RTITB). This is followed by information on RTITB policies and provisions; RTITB members, officers, and committees; apprenticeships and other training schemes;…

  20. Mixing and Transport.

    ERIC Educational Resources Information Center

    Ditmars, John D.

    1978-01-01

    Presents a literature review of longitudinal dispersion, mixing and transport in streams, rivers, lakes, reservoirs, estuaries, and oceans. This review covers also: (1) fluid-solid mixtures and (2) oil spill behavior. A list of 189 references published in 1976 and 1977 is presented. (HM)

  1. Slurry transport medium

    SciTech Connect

    Rosenthal, W.; Schiffman, L.

    1980-06-03

    This invention provides for an improvement in slurry transport systems, especially coal slurry lines. Instead of the usual use of fresh water resources which, in some geographic areas, are scarce for slurry transport, concentrated brine is used which is prepared from abundant salt water resources. Because of the higher density of this concentrated brine, it is a superior carrier of pulverized material. It diminishes the separation and settling tendency of slurry components during transport and particularly during shutdown. Other advantages in the use of concentrated brine include: freezing point depression which permits ease of transport during winter and at lower temperatures; dust suppression of stored coal; avoidance of spontaneous combustion of stored coal; inhibit freeze packing of dewatered pipeline coal; and diminished extent of corrosion in ferrous metal pipelines as compared to that which might occur with lower concentration brines. Important in the economy of the process is that the concentrated brine can be recycled. An inexpensive method for producing the concentrated brine is given.

  2. Transportation fuels: Desulfurizing diesel

    NASA Astrophysics Data System (ADS)

    Lamonier, Carole

    2017-02-01

    Transportation fuels such as diesel contain organosulfur molecules that, when combusted, form sulfur oxides that are toxic and poison vehicles' catalytic convertors. Now, a method is demonstrated that can reduce the sulfur concentration of diesel fuel to very low levels at low temperatures and pressures.

  3. Alternate Transportation Routes

    ERIC Educational Resources Information Center

    Vogel, Carl

    2009-01-01

    Since last school year, the St. Lucie County (Florida) Public Schools reduced the number of buses it operates from 399 to 362, despite opening two new schools. Add in some other smart changes in policy, and the district lowered its annual transportation costs by more than $3 million over last year. Saving $3 million a year does not come easily,…

  4. Negligence in Transporting Students.

    ERIC Educational Resources Information Center

    Wood, R. Craig; Ruch, Robert W.

    1986-01-01

    Discusses areas that have provided the bulk of negligence claims against public school districts while transporting students: (1) bus stop locations, (2) duration of responsibility, (3) school bus boarding supervision, (4) driving a bus negligently, (5) driver violations, and (6) inadequate supervision during transit. Appended are 19 notes. (MLF)

  5. Platelet transport in microchannels

    NASA Astrophysics Data System (ADS)

    Reyssat, Mathilde; Le Goff, Anne; Blin, Antoine; Pujos, Justine; Magniez, Aurélie; Baruch, Dominique

    2013-11-01

    Blood platelets are small enucleated cells responsible for the arrest of bleeding. These cells have the ability to tether and translocate on injured vascular endothelium, thanks to a specific interaction between a receptor of their membrane and a protein expressed by the cells composing the inner wall of the vessel, the von Willebrand factor (VWF). Others cells have such abilities of rolling. Leucocytes, for example, translocate on surface due to a specific interaction between selectin molecules and their respective glycoprotein ligands. These kinds of cells present two modes of transport: they can either be advected by the flux, or translocate on surfaces due to specific ligand-receptor interactions. Our work consists first in studying experimentally the transport of platelets along a microchannel and then in modeling this particular cell transport. Due to these two modes of transport along a channel, platelets adhering to the surface are not equally distributed along the channel axis. We describe the evolution of the density of platelets with time and distance.

  6. TRANSPORTATION TODAY AND TOMORROW.

    ERIC Educational Resources Information Center

    DAILEY, JOHN T.; NEYMAN, CLINTON A., JR.

    THIS READING TEXT WAS DEVELOPED IN A CURRICULUM PROJECT, DESCRIBED IN VT 004 454, ALONG WITH OTHER MATERIALS TO STIMULATE READING ABOUT MECHANICAL AND TECHNOLOGICAL TOPICS AND TO TEACH BASIC VOCATIONAL TALENTS. THE ORGANIZING THEME OF THE TEXT IS TRANSPORTATION AND POWER. MAJOR PORTIONS OF THE BOOK ARE DEVOTED TO PICTURES AND EASY-READING…

  7. Mixing and Transport.

    ERIC Educational Resources Information Center

    Ditmars, John D.

    1978-01-01

    Presents a literature review of longitudinal dispersion, mixing and transport in streams, rivers, lakes, reservoirs, estuaries, and oceans. This review covers also: (1) fluid-solid mixtures and (2) oil spill behavior. A list of 189 references published in 1976 and 1977 is presented. (HM)

  8. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Evren Ozbayoglu; Lei Zhou

    2002-04-30

    This is the third quarterly progress report for Year 3 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between Jan. 1, 2002 and Mar. 31, 2002. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 3: Addition of a Cuttings Injection/Separation System), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 9b): ''Study of Foam Flow Behavior Under EPET Conditions'', (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b); (f) Development of a Safety program for the ACTS Flow Loop, progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S); and (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  9. TRANSPORTATION LONG AGO.

    ERIC Educational Resources Information Center

    George Washington Univ., Washington, DC.

    THIS HISTORICAL REVIEW OF TRANSPORTATION REPRESENTS AN EXPERIMENTAL BOOKLET OF ILLUSTRATIONS AND SINGLE TEXT FOR USE BY TEACHERS TO STIMULATE INTEREST IN READING AND IN RELATED MECHANICAL SUBJECT MATTER AREAS. IT AIMS TO HELP YOUNG PEOPLE LEARN BASIC PRINCIPLES AND CONCEPTS OF MECHANICS AND TECHNOLOGY. PHOTOGRAPHS AND ILLUSTRATIONS, SELECTED FROM…

  10. Child Transportation Safety Tips.

    ERIC Educational Resources Information Center

    National Highway Traffic Safety Administration (DOT), Washington, DC.

    This document presents nine tips regarding safe infant and child transportation, each tip explained in one to two pages. The tips are as follows: (1) quick safety seat checkup; (2) where should your child ride? (3) how to protect your new baby in the car; (4) what safety seat to use for a big baby or toddler? (5) how should preschool and school…

  11. A corporate supersonic transport

    NASA Technical Reports Server (NTRS)

    Greene, Randall; Seebass, Richard

    1996-01-01

    This talk address the market and technology for a corporate supersonic transport. It describes a candidate configuration. There seems to be a sufficient market for such an aircraft, even if restricted to supersonic operation over water. The candidate configuration's sonic boom overpressure may be small enough to allow overland operation as well.

  12. Phloem transport and drought.

    PubMed

    Sevanto, Sanna

    2014-04-01

    Drought challenges plant water uptake and the vascular system. In the xylem it causes embolism that impairs water transport from the soil to the leaves and, if uncontrolled, may even lead to plant mortality via hydraulic failure. What happens in the phloem, however, is less clear because measuring phloem transport is still a significant challenge to plant science. In all vascular plants, phloem and xylem tissues are located next to each other, and there is clear evidence that these tissues exchange water. Therefore, drought should also lead to water shortage in the phloem. In this review, theories used in phloem transport models have been applied to drought conditions, with the goal of shedding light on how phloem transport failure might occur. The review revealed that phloem failure could occur either because of viscosity build-up at the source sites or by a failure to maintain phloem water status and cell turgor. Which one of these dominates depends on the hydraulic permeability of phloem conduit walls. Impermeable walls will lead to viscosity build-up affecting flow rates, while permeable walls make the plant more susceptible to phloem turgor failure. Current empirical evidence suggests that phloem failure resulting from phloem turgor collapse is the more likely mechanism at least in relatively isohydric plants.

  13. Artificial oxygen transport protein

    DOEpatents

    Dutton, P. Leslie

    2014-09-30

    This invention provides heme-containing peptides capable of binding molecular oxygen at room temperature. These compounds may be useful in the absorption of molecular oxygen from molecular oxygen-containing atmospheres. Also included in the invention are methods for treating an oxygen transport deficiency in a mammal.

  14. School Transportation: Administrator's Handbook

    ERIC Educational Resources Information Center

    Missouri Department of Elementary and Secondary Education, 2008

    2008-01-01

    Pupil transportation is an essential part of the overall school program, which requires constant supervision and direction. Perhaps no other phase of the school program is more closely observed by the public or has a greater tendency to mold public opinion about the schools than the school bus system. The success of any school district pupil…

  15. ADVANCED CUTTINGS TRANSPORT STUDY

    SciTech Connect

    Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Evren Ozbayoglu; Lei Zhou

    2002-07-30

    This is the fourth quarterly progress report for Year-3 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between April 1, 2002 and June 30, 2002. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 3: Addition of a Cuttings Injection/Separation System), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)''; (c) Research project (Task 9b): ''Study of Foam Flow Behavior Under EPET Conditions''; (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions''; (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b); (f) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S); (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.

  16. Transportation of Handicapped Children.

    ERIC Educational Resources Information Center

    Flynn, Patricia; And Others

    The booklet presents information and illustrations regarding bus transportation of handicapped children. The roles and responsibilities of drivers and aides are discussed as are such topics as seating arrangements, first aid measures (for falls and seizures), embarking and debarking procedures (including ways to encourage independence in walking),…

  17. Transportation: Destination Mars

    NASA Astrophysics Data System (ADS)

    Eoff, Bill

    1998-01-01

    As the agency space transportation lead center, Marshall Space Flight Center has been conducting transportation assessments for future robotic and human Mars missions to identify critical technologies. Five human Mars options are currently under assessment with each option including all transportation requirements from Earth to Mars and return. The primary difference for each option is the propulsion source from Earth to Mars. In case any of the options require heavy launch capability that is not currently projected as available, an in-house study has been initiated to determine the most cost effective means of providing such launch capability. This assessment is only considering launch architectures that support the overall human Mars mission cost goal of 25B. The guidelines for the launch capability study included delivery of 80 metric ton (176 KLB) payloads, 25 feet diameter x 92 feet long, to 220 nmi orbits at 28.5 degrees. The launch vehicle concept of the study was designated "Magnum" to differentiate from prior heavy launch vehicle assessments. This assessment along with the assessment of options for all transportation phases of a Mars mission are on-going.

  18. Ionic Polymer-Coated Laccase with High Activity and Enhanced Stability: Application in the Decolourisation of Water Containing AO7

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaolin; Hua, Ming; Lv, Lu; Pan, Bingcai

    2015-02-01

    Eliminating dyes in environmental water purification remains a formidable challenge. Laccase is a unique, environmentally friendly and efficient biocatalyst that can degrade pollutants. However, the use of laccase for the degradation of pollutants is considerably limited by its susceptibility to environmental changes and its poor reusability. We fabricated a novel biocatalyst (LacPG) by coating polyethylenimine onto the native laccase (Lac) followed by crosslinking with glutaraldehyde. The stability of the resulting LacPG was highly enhanced against pH variations, thermal treatments and provided better long-term storage with a negligible loss in enzymatic activity. Compared to Lac, LacPG exhibited significantly higher decolourisation efficiency in the degradation of a representative azo dye, acid orange 7 (AO7), which resulted from the electrostatic attraction between the coating and AO7. LacPG was separated from the AO7 solution using an ultrafiltration unit. The increased size and modified surface chemistry of LacPG facilitated ultrafiltration and reduced membrane fouling. LacPG exhibited enhanced stability, high catalytic activity and favourable properties for membrane separation; therefore, LacPG could be continuously reused in an enzymatic membrane reactor with a high efficiency for decolourising water containing AO7. The developed strategy appears to be promising for enhancing the applicability of laccase in practical water treatment.

  19. Ionic Polymer-Coated Laccase with High Activity and Enhanced Stability: Application in the Decolourisation of Water Containing AO7

    PubMed Central

    Zhang, Xiaolin; Hua, Ming; Lv, Lu; Pan, Bingcai

    2015-01-01

    Eliminating dyes in environmental water purification remains a formidable challenge. Laccase is a unique, environmentally friendly and efficient biocatalyst that can degrade pollutants. However, the use of laccase for the degradation of pollutants is considerably limited by its susceptibility to environmental changes and its poor reusability. We fabricated a novel biocatalyst (LacPG) by coating polyethylenimine onto the native laccase (Lac) followed by crosslinking with glutaraldehyde. The stability of the resulting LacPG was highly enhanced against pH variations, thermal treatments and provided better long-term storage with a negligible loss in enzymatic activity. Compared to Lac, LacPG exhibited significantly higher decolourisation efficiency in the degradation of a representative azo dye, acid orange 7 (AO7), which resulted from the electrostatic attraction between the coating and AO7. LacPG was separated from the AO7 solution using an ultrafiltration unit. The increased size and modified surface chemistry of LacPG facilitated ultrafiltration and reduced membrane fouling. LacPG exhibited enhanced stability, high catalytic activity and favourable properties for membrane separation; therefore, LacPG could be continuously reused in an enzymatic membrane reactor with a high efficiency for decolourising water containing AO7. The developed strategy appears to be promising for enhancing the applicability of laccase in practical water treatment. PMID:25652843

  20. Robo-AO Kepler Asteroseismic Survey. I. Adaptive Optics Imaging of 99 Asteroseismic Kepler Dwarfs and Subgiants

    NASA Astrophysics Data System (ADS)

    Schonhut-Stasik, Jessica S.; Baranec, Christoph; Huber, Daniel; Ziegler, Carl; Atkinson, Dani; Gaidos, Eric; Law, Nicholas M.; Riddle, Reed; Hagelberg, Janis; van der Marel, Nienke; Hodapp, Klaus W.

    2017-10-01

    We used the Robo-AO laser adaptive optics (AOs) system to image 99 main sequence and subgiant stars that have Kepler-detected asteroseismic signals. Robo-AO allows us to resolve blended secondary sources at separations as close as ∼0.″15 that may contribute to the measured Kepler light curves and affect asteroseismic analysis and interpretation. We report eight new secondary sources within 4.″0 of these Kepler asteroseismic stars. We used Subaru and Keck AOs to measure differential infrared photometry for these candidate companion systems. Two of the secondary sources are likely foreground objects, while the remaining six are background sources; however, we cannot exclude the possibility that three of the objects may be physically associated. We measured a range of i‧-band amplitude dilutions for the candidate companion systems from 0.43% to 15.4%. We find that the measured amplitude dilutions are insufficient to explain the previously identified excess scatter in the relationship between asteroseismic oscillation amplitude and the frequency of maximum power.

  1. Effect of misalignment of air-coupled probes on Ao Lamb mode propagating in a metal plate.

    PubMed

    Ramadas, C; Hood, Avinash; Khan, Irfan; Balasubramaniam, Krishnan

    2014-07-01

    Proper alignment of air-coupled ultrasonic transducers for generation and reception of Lamb waves is vital in order to acquire a high amplitude wave group. Any misalignment with either the transmitter or the receiver or both adversely influences the amplitude of a Lamb mode. This paper reports a systematic attempt to quantify the reduction in the amplitude of the fundamental anti-symmetric Lamb mode (Ao) in a metal plate caused by misalignments in air-coupled probes. Three different types of misalignments - linear, orientation and synchronised orientation were deliberately introduced in the transducers, and experiments were performed on a 6mm thick aluminium plate. Amplitudes of Ao mode measured at various configurations were normalised with that of Ao mode, captured in a reference configuration. Suitable curves fitted over the experimental data points revealed that Gaussian curves represent appropriately the variations in normalised amplitudes of Ao mode. Moreover, analytical expressions were derived to predict the difference in arrival times of Lamb mode(s) due to orientation and synchronised orientation misalignments.

  2. Project summary: Emerging technology assessment of phostrip, a/o, and bardenpho processes for biological phosphorus removal

    SciTech Connect

    1985-03-01

    This technology assessment addresses the process capabilities and limitations of three proprietary processes (PhoStrip, A/O, and Bardenpho) to biologically remove phosphorus from municipal wastewaters. The primary objective of this report is to provide guidance to individuals involved with reviewing new processes as part of the Innovative and Alternative Technology Program.

  3. Ionic polymer-coated laccase with high activity and enhanced stability: application in the decolourisation of water containing AO7.

    PubMed

    Zhang, Xiaolin; Hua, Ming; Lv, Lu; Pan, Bingcai

    2015-02-05

    Eliminating dyes in environmental water purification remains a formidable challenge. Laccase is a unique, environmentally friendly and efficient biocatalyst that can degrade pollutants. However, the use of laccase for the degradation of pollutants is considerably limited by its susceptibility to environmental changes and its poor reusability. We fabricated a novel biocatalyst (LacPG) by coating polyethylenimine onto the native laccase (Lac) followed by crosslinking with glutaraldehyde. The stability of the resulting LacPG was highly enhanced against pH variations, thermal treatments and provided better long-term storage with a negligible loss in enzymatic activity. Compared to Lac, LacPG exhibited significantly higher decolourisation efficiency in the degradation of a representative azo dye, acid orange 7 (AO7), which resulted from the electrostatic attraction between the coating and AO7. LacPG was separated from the AO7 solution using an ultrafiltration unit. The increased size and modified surface chemistry of LacPG facilitated ultrafiltration and reduced membrane fouling. LacPG exhibited enhanced stability, high catalytic activity and favourable properties for membrane separation; therefore, LacPG could be continuously reused in an enzymatic membrane reactor with a high efficiency for decolourising water containing AO7. The developed strategy appears to be promising for enhancing the applicability of laccase in practical water treatment.

  4. The approbation of rejection method for positional observations of asteroids performed by SBG-telescope AO UFU

    NASA Astrophysics Data System (ADS)

    Galushina, T. Yu.; Skripnichenko, P. V.

    2013-12-01

    The main idea of this investigation has been connected with positional observations rejection method which founded on the analysis of results of the orbit elements improvement. This article contains approbation instances for positional observations per-formed by authors with help of SBG-telescope of AO UFU.

  5. Determinants of cation transport selectivity: Equilibrium binding and transport kinetics

    PubMed Central

    2015-01-01

    The crystal structures of channels and transporters reveal the chemical nature of ion-binding sites and, thereby, constrain mechanistic models for their transport processes. However, these structures, in and of themselves, do not reveal equilibrium selectivity or transport preferences, which can be discerned only from various functional assays. In this Review, I explore the relationship between cation transport protein structures, equilibrium binding measurements, and ion transport selectivity. The primary focus is on K+-selective channels and nonselective cation channels because they have been extensively studied both functionally and structurally, but the principles discussed are relevant to other transport proteins and molecules. PMID:26078056

  6. Saturated Zone Colloid Transport

    SciTech Connect

    H. S. Viswanathan

    2004-10-07

    This scientific analysis provides retardation factors for colloids transporting in the saturated zone (SZ) and the unsaturated zone (UZ). These retardation factors represent the reversible chemical and physical filtration of colloids in the SZ. The value of the colloid retardation factor, R{sub col} is dependent on several factors, such as colloid size, colloid type, and geochemical conditions (e.g., pH, Eh, and ionic strength). These factors are folded into the distributions of R{sub col} that have been developed from field and experimental data collected under varying geochemical conditions with different colloid types and sizes. Attachment rate constants, k{sub att}, and detachment rate constants, k{sub det}, of colloids to the fracture surface have been measured for the fractured volcanics, and separate R{sub col} uncertainty distributions have been developed for attachment and detachment to clastic material and mineral grains in the alluvium. Radionuclides such as plutonium and americium sorb mostly (90 to 99 percent) irreversibly to colloids (BSC 2004 [DIRS 170025], Section 6.3.3.2). The colloid retardation factors developed in this analysis are needed to simulate the transport of radionuclides that are irreversibly sorbed onto colloids; this transport is discussed in the model report ''Site-Scale Saturated Zone Transport'' (BSC 2004 [DIRS 170036]). Although it is not exclusive to any particular radionuclide release scenario, this scientific analysis especially addresses those scenarios pertaining to evidence from waste-degradation experiments, which indicate that plutonium and americium may be irreversibly attached to colloids for the time scales of interest. A section of this report will also discuss the validity of using microspheres as analogs to colloids in some of the lab and field experiments used to obtain the colloid retardation factors. In addition, a small fraction of colloids travels with the groundwater without any significant retardation

  7. Visually Exploring Transportation Schedules.

    PubMed

    Palomo, Cesar; Guo, Zhan; Silva, Cláudio T; Freire, Juliana

    2016-01-01

    Public transportation schedules are designed by agencies to optimize service quality under multiple constraints. However, real service usually deviates from the plan. Therefore, transportation analysts need to identify, compare and explain both eventual and systemic performance issues that must be addressed so that better timetables can be created. The purely statistical tools commonly used by analysts pose many difficulties due to the large number of attributes at trip- and station-level for planned and real service. Also challenging is the need for models at multiple scales to search for patterns at different times and stations, since analysts do not know exactly where or when relevant patterns might emerge and need to compute statistical summaries for multiple attributes at different granularities. To aid in this analysis, we worked in close collaboration with a transportation expert to design TR-EX, a visual exploration tool developed to identify, inspect and compare spatio-temporal patterns for planned and real transportation service. TR-EX combines two new visual encodings inspired by Marey's Train Schedule: Trips Explorer for trip-level analysis of frequency, deviation and speed; and Stops Explorer for station-level study of delay, wait time, reliability and performance deficiencies such as bunching. To tackle overplotting and to provide a robust representation for a large numbers of trips and stops at multiple scales, the system supports variable kernel bandwidths to achieve the level of detail required by users for different tasks. We justify our design decisions based on specific analysis needs of transportation analysts. We provide anecdotal evidence of the efficacy of TR-EX through a series of case studies that explore NYC subway service, which illustrate how TR-EX can be used to confirm hypotheses and derive new insights through visual exploration.

  8. Variability and Period Analysis for BL Lac AO 0235+164

    NASA Astrophysics Data System (ADS)

    Fan, J. H.; Kurtanidze, O.; Liu, Y.; Liu, X.; Yang, J. H.; Richter, G. M.; Nikolashvili, M. G.; Kurtanidze, S. O.; Wang, H. T.; Sasada, M.; Zhou, A. Y.; Lin, C.; Yuan, Y. H.; Zhang, Y. T.; Costantin, D.

    2017-03-01

    Variability is one of the extreme observational properties of BL Lacertae objects. AO 0235+164 is a well-studied BL Lac throughout all electromagnetic wavebands. In the present work, we show its optical R-band photometric observations carried out during the period from 2006 November to 2012 December using the Ap6E CCD camera attached to the primary focus of the 70 cm meniscus telescope at Abastumani Observatory, Georgia. During our monitoring period, it showed a large variation of {{Δ }}R=4.88 {mag} (14.19–19.07 mag) and a short timescale of {{Δ }}{T}v=73.5 {minutes}. During the period of 2006 December to 2009 November, we made radio observations of the source using the 25 m radio telescope at Xinjiang Astronomical Observatory. By adopting a discrete correlation function to the optical and radio observations we found that the optical variation leads a radio variation of 23.2 ± 12.9 days.

  9. Characterization, Expression Profile, and Promoter Analysis of the Rhodeus uyekii Vitellogenin Ao1 Gene

    PubMed Central

    Kong, Hee Jeong; Kim, Ju Lan; Moon, Ji Young; Kim, Woo-Jin; Kim, Hyung Soo; Park, Jung Youn; Cho, Hyun Kook; An, Cheul Min

    2014-01-01

    The fish Vitellogenin (Vg) gene has been applied as a biomarker for exposure to estrogenic compounds in the aquatic environment. In this study, we cloned and characterized Vg cDNA from the Korean rose bitterling Rhodeus uyekii (Ru-Vg). The Ru-Vg cDNA encodes a 1424-amino-acid polypeptide that belongs to the VgAo1 family and contains a putative signal peptide, lipovitellin I, phosvitin, and lipovitellin II, but does not contain the vWFD domain or the C-terminal peptide. The deduced Ru-Vg protein has high amino acid identity (73.97%–32.17%) with fish Vg proteins. Pairwise alignment and phylogenetic analysis revealed that Ru-Vg is most closely related to Acheilognathus yamatsutae Vg. Ru-Vg transcripts were detected using quantitative polymerase chain reaction in all tissues tested, with the highest level of expression observed in the ovary. Ru-Vg mRNA was upregulated in R. uyekii hepatopancreas cells in response to treatment with 17β-estradiol (E2) or 17α-ethinylestradiol (EE2). Luciferase reporter expression, driven by the 5'-regulatory region of the Ru-Vg gene spanning from −1020 bp to the start codon was induced by the estrogen receptor and was synergistically activated by treatment with E2 or EE2. These results suggest that R. uyekii and the Ru-Vg gene may be useful as biomarkers for exposure to E2 or EE2. PMID:25329620

  10. Characterization, expression profile, and promoter analysis of the Rhodeus uyekii vitellogenin Ao1 gene.

    PubMed

    Kong, Hee Jeong; Kim, Ju Lan; Moon, Ji Young; Kim, Woo-Jin; Kim, Hyung Soo; Park, Jung Youn; Cho, Hyun Kook; An, Cheul Min

    2014-10-17

    The fish Vitellogenin (Vg) gene has been applied as a biomarker for exposure to estrogenic compounds in the aquatic environment. In this study, we cloned and characterized Vg cDNA from the Korean rose bitterling Rhodeus uyekii (Ru-Vg). The Ru-Vg cDNA encodes a 1424-amino-acid polypeptide that belongs to the VgAo1 family and contains a putative signal peptide, lipovitellin I, phosvitin, and lipovitellin II, but does not contain the vWFD domain or the C-terminal peptide. The deduced Ru-Vg protein has high amino acid identity (73.97%-32.17%) with fish Vg proteins. Pairwise alignment and phylogenetic analysis revealed that Ru-Vg is most closely related to Acheilognathus yamatsutae Vg. Ru-Vg transcripts were detected using quantitative polymerase chain reaction in all tissues tested, with the highest level of expression observed in the ovary. Ru-Vg mRNA was upregulated in R. uyekii hepatopancreas cells in response to treatment with 17β-estradiol (E2) or 17α-ethinylestradiol (EE2). Luciferase reporter expression, driven by the 5'-regulatory region of the Ru-Vg gene spanning from -1020 bp to the start codon was induced by the estrogen receptor and was synergistically activated by treatment with E2 or EE2. These results suggest that R. uyekii and the Ru-Vg gene may be useful as biomarkers for exposure to E2 or EE2.

  11. Natural guide-star processing for wide-field laser-assisted AO systems

    NASA Astrophysics Data System (ADS)

    Correia, Carlos M.; Neichel, Benoit; Conan, Jean-Marc; Petit, Cyril; Sauvage, Jean-Francois; Fusco, Thierry; Vernet, Joel D. R.; Thatte, Niranjan

    2016-07-01

    Sky-coverage in laser-assisted AO observations largely depends on the system's capability to guide on the faintest natural guide-stars possible. Here we give an up-to-date status of our natural guide-star processing tailored to the European-ELT's visible and near-infrared (0.47 to 2.45 μm) integral field spectrograph - Harmoni. We tour the processing of both the isoplanatic and anisoplanatic tilt modes using the spatio-angular approach whereby the wavefront is estimated directly in the pupil plane avoiding a cumbersome explicit layered estimation on the 35-layer profiles we're currently using. Taking the case of Harmoni, we cover the choice of wave-front sensors, the number and field location of guide-stars, the optimised algorithms to beat down angular anisoplanatism and the performance obtained with different temporal controllers under split high-order/low-order tomography or joint tomography. We consider both atmospheric and far greater telescope wind buffeting disturbances. In addition we provide the sky-coverage estimates thus obtained.

  12. The Robo-AO KOI Survey: Laser Adaptive Optics Imaging of Every Kepler Exoplanet Candidate

    NASA Astrophysics Data System (ADS)

    Ziegler, Carl; Law, Nicholas M.; Baranec, Christoph; Morton, Tim; Riddle, Reed L.

    2016-01-01

    The Robo-AO Kepler Planetary Candidate Survey is observing every Kepler planet candidate host star (KOI) with laser adaptive optics imaging to hunt for blended nearby stars which may be physically associated companions. With the unparalleled efficiency provided by the first fully robotic adaptive optics system, we perform the critical search for nearby stars (0.15" to 4.0" separation with contrasts up to 6 magnitudes) that pollute the observed planetary transit signal, contributing to inaccurate planetary characteristics or astrophysical false positives. We present approximately 3300 high resolution observations of Kepler planetary hosts from 2012-2015, with ~500 observed nearby stars. We measure an overall nearby star probability rate of 16.2±0.8%. With this large dataset, we are uniquely able to explore broad correlations between multiple star systems and the properties of the planets which they host. We then use these clues for insight into the formation and evolution of these exotic systems. Several KOIs of particular interest will be discussed, including possible quadruple star systems hosting planets and updated properties for possible rocky planets orbiting in the habitable zone.

  13. The Robo-AO KOI survey: laser adaptive optics imaging of every Kepler exoplanet candidate

    NASA Astrophysics Data System (ADS)

    Ziegler, Carl; Law, Nicholas M.; Baranec, Christoph; Morton, Tim; Riddle, Reed; Atkinson, Dani; Nofi, Larissa

    2016-07-01

    The Robo-AO Kepler Planetary Candidate Survey is observing every Kepler planet candidate host star (KOI) with laser adaptive optics imaging to hunt for blended nearby stars which may be physically associated companions. With the unparalleled efficiency provided by the first fully robotic adaptive optics system, we perform the critical search for nearby stars (0.15" to 4.0" separation with contrasts up to 6 magnitudes) that dilute the observed planetary transit signal, contributing to inaccurate planetary characteristics or astrophysical false positives. We present 3313 high resolution observations of Kepler planetary hosts from 2012-2015, discovering 479 nearby stars. We measure an overall nearby star probability rate of 14.5+/-0.8%. With this large data set, we are uniquely able to explore broad correlations between multiple star systems and the properties of the planets which they host, providing insight into the formation and evolution of planetary systems in our galaxy. Several KOIs of particular interest will be discussed, including possible quadruple star systems hosting planets and updated properties for possible rocky planets orbiting with in their star's habitable zone.

  14. Strategies to cope with sodium layer profile variations in laser guide star AO systems

    NASA Astrophysics Data System (ADS)

    Ellerbroek, Brent L.

    2014-07-01

    The vertical profile of the mesospheric sodium layer varies significantly on a time scale of one minute. These variations can impact the random and systematic measurement errors of laser guide star Shack-Hartmann wave front sensors, particularly on extremely large telescopes. Sensor performance can be improved by selecting pixel processing weights matched to the sodium layer profile, assuming that the shape of the profile can be measured or estimated in real time. In this paper we describe the magnitude of these effects for the Thirty Meter Telescope AO system NFIRAOS. We review several existing approaches for measuring or estimating the sodium layer profile in real time. We then describe a new method for estimating the profile directly from the laser guide star wave front pixel intensities themselves, jointly with the subaperture tip/tilt measurements. The algorithm used for this purpose is based upon the multi-frame iterative blind deconvolution algorithm from image post processing: Subaperture tip/tilts and the sodium profile are estimated successively, bootstrapping the estimate of each quantity from the previous estimate of the other. We present promising initial simulation results on the potential performance of the algorithm, and suggest areas for future work.

  15. Lifestyle in Curaçao. Smoking, alcohol consumption, eating habits and exercise.

    PubMed

    Grol, M E; Halabi, Y T; Gerstenbluth, I; Alberts, J F; O'Niel, J

    1997-03-01

    The Curaçao Health Study was carried out among a randomized sample (n = 2248, response rate = 85%) of the adult non-institutionalized population in order to assess aspects of lifestyle that may pose health risks. Factors examined were tobacco and alcohol use, eating habits and exercise behaviour. Outcome variables were cross-tabulated by gender, age and socioeconomic status. 17.1% of the participants were smokers and 20.5% were regular drinkers, including 6.3% of the men who consumed alcohol excessively (4 or more glasses of alcohol a day). 75% of the participants did not exercise regularly, 37% did not eat vegetables daily, and half did not eat fruit daily. Other poor eating habits were the addition of extra sugar and salt to prepared food by 33% and 20% of the participants, respectively. On the whole, men had less healthy lifestyles than women, with the exception of exercise behaviour. People of high socioeconomic status (SES) drank less alcohol, and exercised more often than those of low SES. Considering the high prevalence of diabetes mellitus and hypertension in the Caribbean, research on lifestyle factors in other Caribbean countries is required to facilitate the development of regional prevention and intervention programmes.

  16. Long-term stability and temperature variability of Iris AO segmented MEMS deformable mirrors

    NASA Astrophysics Data System (ADS)

    Helmbrecht, M. A.; He, M.; Kempf, C. J.; Marchis, F.

    2016-07-01

    Long-term stability of deformable mirrors (DM) is a critical performance requirement for instruments requiring open-loop corrections. The effects of temperature changes in the DM performance are equally critical for such instruments. This paper investigates the long-term stability of three different Iris AO PTT111 DMs that were calibrated at different times ranging from 13 months to nearly 29 months prior to subsequent testing. Performance testing showed that only a small increase in positioning errors occurred from the initial calibration date to the test dates. The increases in errors ranged from as little as 1.38 nm rms after 18 months to 5.68 nm rms after 29 months. The paper also studies the effects of small temperature changes, up to 6.2°C around room temperature. For three different arrays, the errors ranged from 0.62-1.42 nm rms/°C. Removing the effects of packaging shows that errors are <=0.50 nm rms/°C. Finally, measured data showed that individual segments deformed <=0.11 nm rms/°C when heated.

  17. Laser pointing camera: a valuable tool for the LGS-AO operations

    NASA Astrophysics Data System (ADS)

    Centrone, M.; Bonaccini Calia, D.; Pedichini, F.; Cerruto, A.; Ricciardi, A.; Ambrosino, F.

    2016-07-01

    We describe the design, functionalities and commissioning results of the Laser Pointing Camera, developed at INAF-OAR in collaboration with ESO and Astrel for the 4LGSF of the ESO Adaptive Optics Facility. The LPC has proven a fundamental tool during commissioning and operation of the 4LGSF. It allows to calibrate the pointing and focusing models of the four LGS, to reduce to zero the overhead time for the open-loop acquisition of the LGS in the wavefront sensor. During LGS-AO operation it collects regularly the LGS photometry, the LGS fwhm and the cirrus clouds scattering levels. By recognizing via astrometric software the field stars as well as the multiple LGS, LPC is insensitive to flexures of the laser launch telescope or of the receiver telescope opto-mechanics. We present the Commissioning results of the Laser Pointing Camera, obtained at the ESO VLT during the all 4LGSF Laser Guide Star Units Commissioning, and will discuss its possible extension for the ELT operations.

  18. Eutrophication threatens Caribbean seagrasses - An example from Curaçao and Bonaire.

    PubMed

    Govers, Laura L; Lamers, Leon P M; Bouma, Tjeerd J; de Brouwer, Jan H F; van Katwijk, Marieke M

    2014-12-15

    Seagrass beds are globally declining due to human activities in coastal areas. We here aimed to identify threats from eutrophication to the valuable seagrass beds of Curaçao and Bonaire in the Caribbean, which function as nursery habitats for commercial fish species. We documented surface- and porewater nutrient concentrations, and seagrass nutrient concentrations in 6 bays varying in nutrient loads. Water measurements only provided a momentary snapshot, due to timing, tidal stage, etc., but Thalassia testudinum nutrient concentrations indicated long-term nutrient loads. Nutrient levels in most bays did not raise any concern, but high leaf % P values of Thalassia in Piscadera Bay (∼0.31%) and Spanish Water Bay (∼0.21%) showed that seagrasses may be threatened by eutrophication, due to emergency overflow of waste water and coastal housing. We thus showed that seagrasses may be threatened and measures should be taken to prevent loss of these important nursery areas due to eutrophication. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Ruled and holographic experiment (AO 138-5). [long duration exposure facility

    NASA Technical Reports Server (NTRS)

    Bonnemason, Francis

    1992-01-01

    The AO 138-5 experiment has been designed, via the French Cooperative Payload (FRECOPA) experiment with the aim to study the optical behavior of different diffraction gratings submitted to space vacuum long exposure and solar radiation. Samples were rules and holographic gratings, masters or replica, and some additional control mirrors with various coatings. The experiment was located on the B3, trailing edge of the Long Duration Exposure Facility (LDEF) and has been protected against atomic oxygen flux. The experienced thermal cycling has been evaluated from -23 C to 66 C during the flight, 34,000 orbits. The analysis has been focused on the triple point characterization including light efficiency, wavefront flatness quality and stray light level. Tests were conducted on control mirrors and gratings loaded but not exposed to cosmic dust or solar irradiations. They did not show any significant variations. Solar exposure has damaged the coating reflectivity in the ultraviolet region, the degradation is higher with the gratings, in terms of efficiency. However, wavefront flatness quality and stray light level tests revealed no additional changes.

  20. CHOUGH: implementation and performance of a high-order 4m AO demonstrator

    NASA Astrophysics Data System (ADS)

    Bharmal, Nazim A.; Basden, Alastair G.; Bourgenot, Cyril J.; Black, Martin; Dubbeldam, Cornelis M.; Henry, David M.; Hölck-Santibanez, Daniel; Morris, Timothy J.; Robertson, David J.; Schmoll, Jürgen; Talbot, Robert G.; Younger, Eddy J.; Myers, Richard M.

    2016-07-01

    CHOUGH is a small, fast project to provide an experimental on-sky high-order SCAO capability to the 4.2m WHT telescope. The basic goal has r0-sized sub- apertures with the aim of achieving high-Strehl ratios (> 0:5) in the visible (> 650 nm). It achieves this by including itself into the CANARY experiment: CHOUGH is mounted as a breadboard and intercepts the beam within CANARY via a periscope. In doing so, it takes advantage of the mature CANARY infrastructure, but add new AO capabilities. The key instruments that CHOUGH brings to CANARY are: an atmospheric dispersion compensator; a 32 × 32 (1000 actuator) MEMS deformable mirror; 31 × 31 wavefront sensor; and a complementary (narrow-field) imager. CANARY provides a 241-actuator DM, tip/tilt mirror, and comprehensive off-sky alignment facility together with a RTC. In this work, we describe the CHOUGH sub-systems: backbone, ADC, MEMS-DM, HOWFS, CAWS, and NFSI.

  1. Distal humeral AO type C fracture--analysis of LCP fixation.

    PubMed

    Białas, Adam; Krauze, Paweł; Walenczak, Krzysztof

    2013-01-01

    Distal humeral fractures of type C by AO are serious musculoskeletal injuries, affecting the function of the elbow and upper limb. The authors present the results of treatment of these injuries with the use of two LCP plates. We report on 25 patients aged 26-75 years who were operated on between 2008 and 2010. We examined 20 patients. Treatment results were evaluated basing on patient histories (Oxford Elbow Score), clinical examination (Mayo Elbow Score) and radiographs. We rated the percentage loss of movement in relation to the healthy limb. Bony union was achieved in all patients. A scoring system based on the Oxford Elbow Scale rated the outcomes as excellent and good in 13 (65%) patients, fair in 5 (25%) and poor in 2 (10%). The Mayo Elbow Scale revealed 12 (60%) excellent and good results, 6 (30%) fair results and 2 (10%) poor results. Restoration of elbow anatomy with stable fixation of bone fragments allows early resumption of movements, predicting a good clinical outcome.

  2. Vitamin D deficiency in risk groups living in tropical Curaçao.

    PubMed

    Leenders, T J M; van Eijndhoven, F H A; van der Veer, E; Muskiet, F A J

    2013-03-01

    Curaçao (12 degrees 10ON, 69 degrees OW) is characterized by whole year abundant sunshine (8-10 hours/day). We challenged the automatic assumption that people living in tropical countries do not have a high risk of vitamin D deficiency, and investigated the vitamin D status in a tropical environment. For this, we selected fifty-two elderly people with little or no exposure to direct sunlight [median 84 (60-96) years; 34females, 18 males] and who were cared for by community nurses or lived in retirement or nursing homes. Furthermore, six rehabilitating orthopaedic patients [median 72 (38-90) years; one female, five males] were included. Serum 25(OH)D, calcium, phosphate, parathyroid hormone (PTH) and creatinine were measured. Those exhibiting elevated creatinine, PTH or both had their 1,25-dihydroxyvitamin D [1,25(OH)2D] examined. Serum levels of 25(OH)D below 25, 50 and 75 nmol/L were detected in, respectively, seven (12%), 22 (38%) and 48 (83%) ofthe fifty-eight persons. Four persons had combined high creatinine and PTH, and low 1,25(OH)2D, which was not known by their caregivers. Abundant sunshine outdoors is no guarantee for vitamin D sufficiency. More attention is needed for vitamin D deficiency in risk groups living in tropical areas and elderly persons with poor kidney function.

  3. Documentation of fracture severity with the AO classification of pediatric long-bone fractures.

    PubMed

    Slongo, Theddy; Audigé, Laurent; Lutz, Nicolas; Frick, Steve; Schmittenbecher, Peter; Hunter, James; Clavert, Jean-Michel

    2007-04-01

    The AO comprehensive pediatric longbone fracture classification system describes the localization and morphology of fractures, and considers severity in 3 categories: (1) simple, (2) wedge, and (3) complex. We evaluated the reliability and accuracy of surgeons in using this rating system. In a first validation phase, 5 experienced pediatric (orthopedic) surgeons reviewed radiographs of 267 prospectively collected pediatric fractures (agreement study A). In a second study (B), 70 surgeons of various levels of experience in 15 clinics classified 275 fractures via internet. Simple fractures comprised about 90%, 99% and 100% of diaphyseal (D), metaphyseal (M), and epiphyseal (E) fractures, respectively. Kappa coefficients for severity coding in D fractures were 0.82 and 0.51 in studies A and B, respectively. The median accuracy of surgeons in classifying simple fractures was above 97% in both studies but was lower, 85% (46-100), for wedge or complex D fractures. While reliability and accuracy estimates were satisfactory as a whole, the ratings of some individual surgeons were inadequate. Our findings suggest that the classification of fracture severity in children should be done in only two categories that distinguish between simple and wedge/complex fractures.

  4. Laser testing of an Iris AO dielectric-coated segmented MEMS DM

    NASA Astrophysics Data System (ADS)

    Helmbrecht, Michael A.; He, Min; Norton, Andrew P.; Gavel, Donald T.

    2011-09-01

    Iris AO has been developing dielectric-coated segmented MEMS deformable mirrors (DM) for use in laser applications that range from 355-1540 nm. In order to mitigate deformation from residual stress in the thick dielectric coatings, a stress-compensation layer has been added to the underside if the DM segments. This paper describes fabrication results of DMs with high reflectance dielectric coatings for 532 nm, 1064 nm, and 1540 nm. Additionally, a DM with a 532 nm coating has been tested with a 2 W, 532 nm CW laser. Laser testing shows the DM can handle 300 W/cm2 with off-theshelf packaging. Projections show that with good heat sinking, the same DM can handle laser power densities of 2800 W/cm2. The coatings showed no signs of damage after exposure to a w0=25 μm beam with a power density of 205 kW/cm2 for 105 minutes at the center of a segment and at segment edges exposed to 180 kW/cm2 for 45 minutes.

  5. High-power visible-laser effect on a 37-segment Iris AO deformable mirror

    NASA Astrophysics Data System (ADS)

    Norton, Andrew; Gavel, Donald; Dillon, Daren

    2010-02-01

    We have tested an aluminum-coated Iris AO Micro-Electrical Mechanical System (MEMS) segmented Deformable Mirror (DM) for its behavior in the presence of high energy 532 nm laser light. The DM was subject to several tests in which the laser power and the duration of its incidence was varied. The DM experienced an irradiance of 94.5 W cm-2 at the maximum laser power of 2 W. A slight permanent reduction in the amount of bow in each segment was observed. This is most likely due to annealing. The mirror remained fully functional during and after the tests. Measurements of the mirror's temporal stability and position repeatability were performed before the laser test. We found a 1.28 nm rms variation in the bow of segments that is highly correlated over the 16 minute test. The mirror's ability to return to its initial position was within the 1.34 nm rms instrument noise. These results are encouraging for applications such as the laser uplink correction of the Visible Light Laser Guidestar Experiment (Villages) and future multi-Laser Guidestar systems (LGS).

  6. Ultraviolet spectral behavior of AO Psc and V1223 Sgr from the HST and IUE satellites

    NASA Astrophysics Data System (ADS)

    Sanad, M. R.

    2015-03-01

    We present a spectroscopic study of two intermediate polar systems, AO Psc and V1223 Sgr observed with the Hubble Space Telescope Space Telescope Imaging Spectrograph (HST STIS) and International Ultraviolet Explorer (IUE) during the period 1980-2000. The reddening of two systems is determined from the 2200 Å feature. The ultraviolet emission lines are originating in the accretion disk as a result of existing an extra component of emission in the EUV/soft X-ray range with luminosity comparable to the accretion luminosity which reprocessed to produce the observed ultraviolet line strengths. Different spectra for both systems showing the variations in line fluxes at different orbital phases are presented. We concentrated on calculating the line fluxes of C IV 1550 Å & He II 1640 Å emission lines. From HST and IUE data, we derived an accretion luminosities and an accretion rates for two systems. Our results show that there are variations in line fluxes, accretion luminosities and accretion rates with time for two systems. These variations are attributed to the variations of both density and temperature as a result of a changing rate of mass transfer from the secondary star to the white dwarf. These results from the IUE and HST observations are consistent with the models of Ko et al. (Astrophys. J., 457:363K, 1996).

  7. ORBITAL PERIOD CHANGES AND THEIR EVOLUTIONARY STATUS FOR THE WEAK-CONTACT BINARIES. III. AO CAMELOPARDALIS AND AH TAURI

    SciTech Connect

    Yang, Y.-G.; Wei, J.-Y.; Li, H.-L.; Kreiner, J. M. E-mail: sfkreine@cyf-kr.edu.pl

    2010-01-15

    In this paper, we presented multicolor photometric observations for two eclipsing binaries, AO Camelopardalis and AH Tauri, obtained on 2008 December 16 and 17. Using the Wilson-Devinney Code, the photometric solution of AH Tau was determined from our new CCD data. The mass ratio and the fill-out factor are q = 0.503({+-}0.003) and f = 10.8%({+-}0.1%), respectively. This indicates that AH Tau is in weak contact. For the weak-contact binary AO Cam, BVI light curves clearly show a difference in the heights of the maxima (i.e., the O'Connell effect), which may be explained by spot activity. By analyzing the O - C curves for AO Cam and AH Tau, it is found that the orbital periods appear to show a secular period decrease with a cyclic variation. The observed period modulation is {delta}P/P {approx} 10{sup -6}. For AO Cam, the cyclic oscillation with a short period of 7.63({+-}0.07) yr and a low amplitude of 0fd0019({+-}0fd0003) may be preferably attributed to the cyclic magnetic activity. The period and amplitude of the cyclic variation for AH Tau are 45.8({+-}1.1) yr and 0fd0171({+-}0fd0005), which may more likely result from the light-time effect via a third body. The secular period decrease rates are dP/dt = -1.26({+-}0.04) x 10{sup -7} days yr {sup -1} for AO Cam and dP/dt = -6.98({+-}0.07) x 10{sup -8} days yr {sup -1} for AH Tau. This kind of period decrease can be plausibly explained by the mass transfer from the primary to the secondary, and may result in the system evolving into a deep contact configuration.

  8. The heavy metal tolerant soil bacterium Achromobacter sp. AO22 contains a unique copper homeostasis locus and two mer operons.

    PubMed

    Ng, Shee Ping; Palombo, Enzo A; Bhave, Mrinal

    2012-06-01

    Copper-containing compounds are introduced into the environment through agricultural chemicals, mining, and metal industries and cause severe detrimental effects on ecosystems. Certain microorganisms exposed to these stressors exhibit molecular mechanisms to maintain intracellular copper homeostasis and avoid toxicity. We have previously reported that the soil bacterial isolate Achromobacter sp. AO22 is multi-heavy metal tolerant and exhibits a mer operon associated with a Tn21 type transposon. The present study reports that AO22 also hosts a unique cop locus encoding copper homeostasis determinants. The putative cop genes were amplified from the strain AO22 using degenerate primers based on reported cop and pco sequences, and a constructed 10,552 base pair contig (GenBank Accession No. GU929214). BLAST analyses of the sequence revealed a unique cop locus of 10 complete open reading frames, designated copSRABGOFCDK, with unusual separation of copCD from copAB. The promoter areas exhibit two putative cop boxes, and copRS appear to be transcribed divergently from other genes. The putative protein CopA may be a copper oxidase involved in export to the periplasm, CopB is likely extracytoplasmic, CopC may be periplasmic, CopD is cytoplasmic/ inner membrane, CopF is a P-type ATPase, and CopG, CopO, and CopK are likely copper chaperones. CopA, B, C, and D exhibit several potential copper ligands and CopS and CopR exhibit features of two-component regulatory systems. Sequences flanking indicate the AO22 cop locus may be present within a genomic island. Achromobacter sp. strain AO22 is thus an ideal candidate for understanding copper homeostasis mechanisms and exploiting them for copper biosensor or biosorption systems.

  9. Subaru/SCExAO First-light Direct Imaging of a Young Debris Disk around HD 36546

    NASA Astrophysics Data System (ADS)

    Currie, Thayne; Guyon, Olivier; Tamura, Motohide; Kudo, Tomoyuki; Jovanovic, Nemanja; Lozi, Julien; Schlieder, Joshua E.; Brandt, Timothy D.; Kuhn, Jonas; Serabyn, Eugene; Janson, Markus; Carson, Joseph; Groff, Tyler; Kasdin, N. Jeremy; McElwain, Michael W.; Singh, Garima; Uyama, Taichi; Kuzuhara, Masayuki; Akiyama, Eiji; Grady, Carol; Hayashi, Saeko; Knapp, Gillian; Kwon, Jung-mi; Oh, Daehyeon; Wisniewski, John; Sitko, Michael; Yang, Yi

    2017-02-01

    We present H-band scattered light imaging of a bright debris disk around the A0 star HD 36546 obtained from the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system with data recorded by the HiCIAO camera using the vector vortex coronagraph. SCExAO traces the disk from r ∼ 0.″3 to r ∼ 1″ (34–114 au). The disk is oriented in a near east–west direction (PA ∼ 75°), is inclined by i ∼ 70°–75°, and is strongly forward-scattering (g > 0.5). It is an extended disk rather than a sharp ring; a second, diffuse dust population extends from the disk’s eastern side. While HD 36546 intrinsic properties are consistent with a wide age range (t ∼ 1–250 Myr), its kinematics and analysis of coeval stars suggest a young age (3–10 Myr) and a possible connection to Taurus-Auriga’s star formation history. SCExAO’s planet-to-star contrast ratios are comparable to the first-light Gemini Planet Imager contrasts; for an age of 10 Myr, we rule out planets with masses comparable to HR 8799 b beyond a projected separation of 23 au. A massive icy planetesimal disk or an unseen super-Jovian planet at r > 20 au may explain the disk’s visibility. The HD 36546 debris disk may be the youngest debris disk yet imaged, is the first newly identified object from the now-operational SCExAO extreme AO system, is ideally suited for spectroscopic follow-up with SCExAO/CHARIS in 2017, and may be a key probe of icy planet formation and planet–disk interactions.

  10. Chaotic transport in dynamical systems

    NASA Astrophysics Data System (ADS)

    Wiggins, Stephen

    The subject of chaotic transport in dynamical systems is examined from the viewpoint of problems of phase space transport. The examples considered include uniform elliptical vortices in external linear time-dependent velocity fields; capture and passage through resonance in celestial mechanics; bubble dynamics in straining flows; and photodissociation of molecules. The discussion covers transport in two-dimensional maps; convective mixing and transport problems in fluid mechanics; transport in quasi-periodically forced systems; Markov models; and transport in k-degree-of-freedom Hamiltonian systems.

  11. Structural diversity of ABC transporters

    PubMed Central

    ter Beek, Josy; Guskov, Albert

    2014-01-01

    ATP-binding cassette (ABC) transporters form a large superfamily of ATP-dependent protein complexes that mediate transport of a vast array of substrates across membranes. The 14 currently available structures of ABC transporters have greatly advanced insight into the transport mechanism and revealed a tremendous structural diversity. Whereas the domains that hydrolyze ATP are structurally related in all ABC transporters, the membrane-embedded domains, where the substrates are translocated, adopt four different unrelated folds. Here, we review the structural characteristics of ABC transporters and discuss the implications of this structural diversity for mechanistic diversity. PMID:24638992

  12. Transporter taxonomy - a comparison of different transport protein classification schemes.

    PubMed

    Viereck, Michael; Gaulton, Anna; Digles, Daniela; Ecker, Gerhard F

    2014-06-01

    Currently, there are more than 800 well characterized human membrane transport proteins (including channels and transporters) and there are estimates that about 10% (approx. 2000) of all human genes are related to transport. Membrane transport proteins are of interest as potential drug targets, for drug delivery, and as a cause of side effects and drug–drug interactions. In light of the development of Open PHACTS, which provides an open pharmacological space, we analyzed selected membrane transport protein classification schemes (Transporter Classification Database, ChEMBL, IUPHAR/BPS Guide to Pharmacology, and Gene Ontology) for their ability to serve as a basis for pharmacology driven protein classification. A comparison of these membrane transport protein classification schemes by using a set of clinically relevant transporters as use-case reveals the strengths and weaknesses of the different taxonomy approaches.

  13. EBS Radionuclide Transport Abstraction

    SciTech Connect

    R. Schreiner

    2001-06-27

    The purpose of this work is to develop the Engineered Barrier System (EBS) radionuclide transport abstraction model, as directed by a written development plan (CRWMS M&O 1999a). This abstraction is the conceptual model that will be used to determine the rate of release of radionuclides from the EBS to the unsaturated zone (UZ) in the total system performance assessment-license application (TSPA-LA). In particular, this model will be used to quantify the time-dependent radionuclide releases from a failed waste package (WP) and their subsequent transport through the EBS to the emplacement drift wall/UZ interface. The development of this conceptual model will allow Performance Assessment Operations (PAO) and its Engineered Barrier Performance Department to provide a more detailed and complete EBS flow and transport abstraction. The results from this conceptual model will allow PA0 to address portions of the key technical issues (KTIs) presented in three NRC Issue Resolution Status Reports (IRSRs): (1) the Evolution of the Near-Field Environment (ENFE), Revision 2 (NRC 1999a), (2) the Container Life and Source Term (CLST), Revision 2 (NRC 1999b), and (3) the Thermal Effects on Flow (TEF), Revision 1 (NRC 1998). The conceptual model for flow and transport in the EBS will be referred to as the ''EBS RT Abstraction'' in this analysis/modeling report (AMR). The scope of this abstraction and report is limited to flow and transport processes. More specifically, this AMR does not discuss elements of the TSPA-SR and TSPA-LA that relate to the EBS but are discussed in other AMRs. These elements include corrosion processes, radionuclide solubility limits, waste form dissolution rates and concentrations of colloidal particles that are generally represented as boundary conditions or input parameters for the EBS RT Abstraction. In effect, this AMR provides the algorithms for transporting radionuclides using the flow geometry and radionuclide concentrations determined by other

  14. Cysteine transport through excitatory amino acid transporter 3 (EAAT3).

    PubMed

    Watts, Spencer D; Torres-Salazar, Delany; Divito, Christopher B; Amara, Susan G

    2014-01-01

    Excitatory amino acid transporters (EAATs) limit glutamatergic signaling and maintain extracellular glutamate concentrations below neurotoxic levels. Of the five known EAAT isoforms (EAATs 1-5), only the neuronal isoform, EAAT3 (EAAC1), can efficiently transport the uncharged amino acid L-cysteine. EAAT3-mediated cysteine transport has been proposed to be a primary mechanism used by neurons to obtain cysteine for the synthesis of glutathione, a key molecule in preventing oxidative stress and neuronal toxicity. The molecular mechanisms underlying the selective transport of cysteine by EAAT3 have not been elucidated. Here we propose that the transport of cysteine through EAAT3 requires formation of the thiolate form of cysteine in the binding site. Using Xenopus oocytes and HEK293 cells expressing EAAT2 and EAAT3, we assessed the transport kinetics of different substrates and measured transporter-associated currents electrophysiologically. Our results show that L-selenocysteine, a cysteine analog that forms a negatively-charged selenolate ion at physiological pH, is efficiently transported by EAATs 1-3 and has a much higher apparent affinity for transport when compared to cysteine. Using a membrane tethered GFP variant to monitor intracellular pH changes associated with transport activity, we observed that transport of either L-glutamate or L-selenocysteine by EAAT3 decreased intracellular pH, whereas transport of cysteine resulted in cytoplasmic alkalinization. No change in pH was observed when cysteine was applied to cells expressing EAAT2, which displays negligible transport of cysteine. Under conditions that favor release of intracellular substrates through EAAT3 we observed release of labeled intracellular glutamate but did not detect cysteine release. Our results support a model whereby cysteine transport through EAAT3 is facilitated through cysteine de-protonation and that once inside, the thiolate is rapidly re-protonated. Moreover, these findings suggest

  15. Ambipolar charge transport in "traditional" organic hole transport layers.

    PubMed

    Khademi, S; Song, J Y; Wyatt, P B; Kreouzis, T; Gillin, W P

    2012-05-02

    Organic semiconductors are often labeled as electron or hole transport materials due to the primary role they perform in devices. However, despite these labels we have shown using time-of-flight that two of the traditional "hole transport materials" TPD and NPB are actually excellent electron transporters the electron transport properties of which are comparable to those for holes. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Is the Standard Definition of Poleward Heat Transport Appropriate in Climate Research?

    NASA Astrophysics Data System (ADS)

    Liang, Minyi; Czaja, Arnaud; Graversen, Rune; Tailleux, Remi

    2016-04-01

    In this paper, a problem with the standard definition of poleward heat transport is highlighted. This, we argue, arises because of the dependence of the standard definition on an arbitrary reference state for moist static energy. This dependence may result in large uncertainty in the estimates of ocean-atmosphere coupling, the signature in heat transport of the atmospheric storm track and annular modes of variability. A new definition is proposed to address the problem, which removes unrealistically large fluctuations (4PW) found when using the standard definition. A practical way to implement the new formulation is also discussed. The new heat transport definition is shown to lead to better correlations with climate indices compared to the traditional definition. In particular a clear relationship between the AO, El Niño and heat transport emerges in our analysis. In addition, it also produces different time sequence of event with large/weak poleward heat transport. It is hoped that the new heat transport definition may shed light on studies exploring the link between energy transport and climate variability.

  17. Mass Transport within Soils

    SciTech Connect

    McKone, Thomas E.

    2009-03-01

    Contaminants in soil can impact human health and the environment through a complex web of interactions. Soils exist where the atmosphere, hydrosphere, geosphere, and biosphere converge. Soil is the thin outer zone of the earth's crust that supports rooted plants and is the product of climate and living organisms acting on rock. A true soil is a mixture of air, water, mineral, and organic components. The relative proportions of these components determine the value of the soil for agricultural and for other human uses. These proportions also determine, to a large extent, how a substance added to soil is transported and/or transformed within the soil (Spositio, 2004). In mass-balance models, soil compartments play a major role, functioning both as reservoirs and as the principal media for transport among air, vegetation, surface water, deeper soil, and ground water (Mackay, 2001). Quantifying the mass transport of chemicals within soil and between soil and atmosphere is important for understanding the role soil plays in controlling fate, transport, and exposure to multimedia pollutants. Soils are characteristically heterogeneous. A trench dug into soil typically reveals several horizontal layers having different colors and textures. As illustrated in Figure 1, these multiple layers are often divided into three major horizons: (1) the A horizon, which encompasses the root zone and contains a high concentration of organic matter; (2) the B horizon, which is unsaturated, lies below the roots of most plants, and contains a much lower organic carbon content; and (3) the C horizon, which is the unsaturated zone of weathered parent rock consisting of bedrock, alluvial material, glacial material, and/or soil of an earlier geological period. Below these three horizons lies the saturated zone - a zone that encompasses the area below ground surface in which all interconnected openings within the geologic media are completely filled with water. Similarly to the unsaturated zone

  18. The cost of transportation`s oil dependence

    SciTech Connect

    Greene, D.L.

    1995-05-01

    Transportation is critical to the world`s oil dependence problem because of the large share of world oil it consumes and because of its intense dependence on oil. This paper will focus on the economic costs of transportation`s oil dependence.

  19. Cellular iron transport.

    PubMed

    Garrick, Michael D; Garrick, Laura M

    2009-05-01

    Iron has a split personality as an essential nutrient that also has the potential to generate reactive oxygen species. We discuss how different cell types within specific tissues manage this schizophrenia. The emphasis in enterocytes is on regulating the body's supply of iron by regulating transport into the blood stream. In developing red blood cells, adaptations in transport manage the body's highest flux of iron. Hepatocytes buffer the body's stock of iron. Macrophage recycle the iron from effete red cells among other iron management tasks. Pneumocytes provide a barrier to prevent illicit entry that, when at risk of breaching, leads to a need to handle the dangers in a fashion essentially shared with macrophage. We also discuss or introduce cell types including renal cells, neurons, other brain cells, and more where our ignorance, currently still vast, needs to be removed by future research.

  20. Transportation Systems Evaluation

    NASA Technical Reports Server (NTRS)

    Fanning, M. L.; Michelson, R. A.

    1972-01-01

    A methodology for the analysis of transportation systems consisting of five major interacting elements is reported. The analysis begins with the causes of travel demand: geographic, economic, and demographic characteristics as well as attitudes toward travel. Through the analysis, the interaction of these factors with the physical and economic characteristics of the transportation system is determined. The result is an evaluation of the system from the point of view of both passenger and operator. The methodology is applicable to the intraurban transit systems as well as major airlines. Applications of the technique to analysis of a PRT system and a study of intraurban air travel are given. In the discussion several unique models or techniques are mentioned: i.e., passenger preference modeling, an integrated intraurban transit model, and a series of models to perform airline analysis.

  1. Saturated Zone Colloid Transport

    SciTech Connect

    H. Viswanathan; P. Reimus

    2003-09-05

    Colloid retardation is influenced by the attachment and detachment of colloids from immobile surfaces. This analysis demonstrates the development of parameters necessary to estimate attachment and detachment of colloids and, hence, retardation in both fractured tuff and porous alluvium. Field and experimental data specific to fractured tuff are used for the analysis of colloid retardation in fractured tuff. Experimental data specific to colloid transport in alluvial material from Yucca Mountain as well as bacteriophage field studies in alluvial material, which are thought to be good analogs for colloid transport, are used to estimate attachment and detachment of colloids in the alluvial material. There are no alternative scientific approaches or technical methods for calculating these retardation factors.

  2. An Artificial Molecular Transporter

    PubMed Central

    Schäfer, Christian; Ragazzon, Giulio; Colasson, Benoit; La Rosa, Marcello; Silvi, Serena

    2015-01-01

    Abstract The transport of substrates is one of the main tasks of biomolecular machines in living organisms. We report a synthetic small‐molecule system designed to catch, displace, and release molecular cargo in solution under external control. The system consists of a bistable rotaxane that behaves as an acid–base controlled molecular shuttle, whose ring component bears a tether ending with a nitrile group. The latter can be coordinated to a ruthenium complex that acts as the load, and dissociated upon irradiation with visible light. The cargo loading/unloading and ring transfer/return processes are reversible and can be controlled independently. The robust coordination bond ensures that the cargo remains attached to the device while the transport takes place. PMID:27308223

  3. Fuel cell water transport

    DOEpatents

    Vanderborgh, Nicholas E.; Hedstrom, James C.

    1990-01-01

    The moisture content and temperature of hydrogen and oxygen gases is regulated throughout traverse of the gases in a fuel cell incorporating a solid polymer membrane. At least one of the gases traverses a first flow field adjacent the solid polymer membrane, where chemical reactions occur to generate an electrical current. A second flow field is located sequential with the first flow field and incorporates a membrane for effective water transport. A control fluid is then circulated adjacent the second membrane on the face opposite the fuel cell gas wherein moisture is either transported from the control fluid to humidify a fuel gas, e.g., hydrogen, or to the control fluid to prevent excess water buildup in the oxidizer gas, e.g., oxygen. Evaporation of water into the control gas and the control gas temperature act to control the fuel cell gas temperatures throughout the traverse of the fuel cell by the gases.

  4. Fractional lattice charge transport

    PubMed Central

    Flach, Sergej; Khomeriki, Ramaz

    2017-01-01

    We consider the dynamics of noninteracting quantum particles on a square lattice in the presence of a magnetic flux α and a dc electric field E oriented along the lattice diagonal. In general, the adiabatic dynamics will be characterized by Bloch oscillations in the electrical field direction and dispersive ballistic transport in the perpendicular direction. For rational values of α and a corresponding discrete set of values of E(α) vanishing gaps in the spectrum induce a fractionalization of the charge in the perpendicular direction - while left movers are still performing dispersive ballistic transport, the complementary fraction of right movers is propagating in a dispersionless relativistic manner in the opposite direction. Generalizations and the possible probing of the effect with atomic Bose-Einstein condensates and photonic networks are discussed. Zak phase of respective band associated with gap closing regime has been computed and it is found converging to π/2 value. PMID:28102302

  5. Jet Transport Rejected Takeoffs.

    DTIC Science & Technology

    1977-02-01

    r _ _ _ _ _ _ N AD—A05 6 032 FEDERAL AVIATIO N ADMINISTRATION WASHINGTON 0 C FLIGHT—ETC FIG 1/2 ~,JET TRANSPORT REJECTED TAKEOFFS • (U)FED 77 0 S...AF~~16O-77-2 FOR FURTHER IRAN JET TRANSPORT R&JECTED TAKEDFFS DAVID W. OSTROWSKILI~~ H c ,~ ~~~~ C ...) ~~~~ O~ —1 w DDU FEB~JARY 1977U... FINAL...Pag. .po ,t No. 2 C.o.,,nm.rr, A c c . s s on No . 3. R.c ,pr. ns s Cat alog No. AFS-16~~-77-2_ j

  6. Mars transportation system

    NASA Technical Reports Server (NTRS)

    Garrard, William; Vano, Andrew; Rutherford, Dave

    1992-01-01

    The University of Minnesota Advanced Space Design Program has developed a sample Mars exploration scenario. The purpose of the design project is to enhance NASA and university interaction, to provide fresh ideas to NASA, and to provide real world design problems to engineering students. The Mars Transportation System in this paper is designed to transport a crew of six astronauts to the Martian surface and return them to Low Earth Orbit (LEO) starting in the year 2016. The proposed vehicle features such advanced technologies as nuclear propulsion, nuclear power generation, and aerobraking. Three missions are planned. Orbital trajectories are of the conjunction class with an inbound Venus swingby providing a 60-day surface stay at Mars and an average total trip time of 520 days.

  7. High speed civil transport

    NASA Technical Reports Server (NTRS)

    Bogardus, Scott; Loper, Brent; Nauman, Chris; Page, Jeff; Parris, Rusty; Steinbach, Greg

    1990-01-01

    The design process of the High Speed Civil Transport (HSCT) combines existing technology with the expectation of future technology to create a Mach 3.0 transport. The HSCT was designed to have a range in excess of 6000 nautical miles and carry up to 300 passengers. This range will allow the HSCT to service the economically expanding Pacific Basin region. Effort was made in the design to enable the aircraft to use conventional airports with standard 12,000 foot runways. With a takeoff thrust of 250,000 pounds, the four supersonic through-flow engines will accelerate the HSCT to a cruise speed of Mach 3.0. The 679,000 pound (at takeoff) HSCT is designed to cruise at an altitude of 70,000 feet, flying above most atmospheric disturbances.

  8. Transportation and the marketplace

    SciTech Connect

    Soeoet, S.

    1996-12-31

    In the Chicago six-county metropolitan area, the number of registered vehicles grew by over 800,000 vehicles in the 1980s; by contrast the population increased by just over 150,000 during the same time. This ratio of growth in automobiles versus population (five to one) has contributed to overall increases in travel, congestion and energy use. The objective of this report is to examine how and why this has occurred and what we might expect in the near future to address the growing traffic problems and energy use. Specifically, the focus is on energy use by household vehicles and other forms of passenger travel. Data on population trends, gasoline prices, commuting and transit use, and transportation energy use are presented and interpreted. Intelligent transportation systems and decreased single vehicle emissions are briefly described as methods to decrease congestion and pollution. 9 figs., 2 tabs.

  9. Soil Transport Implement

    NASA Technical Reports Server (NTRS)

    Dixon, William; Fan, William; Lloyd, Joey; Pham, Nam-Anh; Stevens, Michael

    1988-01-01

    The design of the Soil Transport Implement (STI) for SKITTER is presented. The purpose of STI is to provide a protective layer of lunar soil for the lunar modules. The objective is to cover the lunar module with a layer of soil approximately two meters thick within a two week period. The amount of soil required to cover the module is roughly 77 dump truck loads or three million earth pounds. A spinning disk is employed to accomplish its task. STI is an autonomous, teleoperated system. The design incorporates the latest advances in composite materials and high strength, light weight alloys to achieve a high strength to weight ratio. The preliminary design should only be used to assess the feasibility of employing a spinning wheel as a soil transport implement. A mathematical model of the spinning wheel was used to evaluate the performance of this design.

  10. Insuring RLV transportation services

    NASA Astrophysics Data System (ADS)

    Greenberg, Joel S.

    1998-01-01

    Future deliveries of payloads to orbit are likely to utilize space transportation services that employ a fleet of reusable launch vehicles. To achieve this capability will require the investment of billions of dollars. Such sizable investments will require the formulation of detailed business plans that demonstrate the financial viability of the proposed business and that the business can function within an acceptable level of risk. Besides coping with the normal business risks associated with achievable level of technical performance, demand for launch services, competition, etc., the business must also cope with the risks associated with transportation system failures and delays. This requires the development of a viable risk management plan. This paper is concerned with describing a risk management scenario that can demonstrate and provide an assurance, at the time that investment decisions must be made, that the necessary insurance cover at affordable prices will be available.

  11. Technology transfer: Transportation

    NASA Technical Reports Server (NTRS)

    Anyos, T.; Christy, L.; Lizak, R.; Wilhelm, J.

    1978-01-01

    The successful application of aerospace technology to problems related to highways and rail and rapid transit systems is described with emphasis on the use of corrosion resistant paints, fire retardant materials, and law enforcement. Possible areas for the use of spinoff from NASA technology by the California State Department of Corrections are identified. These include drug detection, security and warning systems, and the transportation and storage of food. A communication system for emergency services is also described.

  12. Melatonin transport into mitochondria.

    PubMed

    Mayo, Juan C; Sainz, Rosa M; González-Menéndez, Pedro; Hevia, David; Cernuda-Cernuda, Rafael

    2017-08-21

    Melatonin is a well-known, nighttime-produced indole found in bacteria, eukaryotic unicellulars, animals or vascular plants. In vertebrates, melatonin is the major product of the pineal gland, which accounts for its increase in serum during the dark phase, but it is also produced by many other organs and cell types. Such a wide distribution is consistent with its multiple and well-described functions which include from the circadian regulation and adaptation to seasonal variations to immunomodulatory and oncostatic actions in different types of tumors. The discovery of its antioxidant properties in the early 1990s opened a new field of potential protective functions in multiple tissues. A special mention should be made regarding the nervous system, where the indole is considered a major neuroprotector. Furthermore, mitochondria appear as one of the most important targets for the indole's protective actions. Melatonin's mechanisms of action vary from the direct molecular interaction with free radicals (free radical scavenger) to the binding to membrane (MLT1A and MLT1B) or nuclear receptors (RZR/RORα). Receptor binding has been associated with some, but not all of the indole functions reported to date. Recently, two new mechanisms of cellular uptake involving the facilitative glucose transporters GLUT/SLC2A and the proton-driven oligopeptide transporter PEPT1/2 have been reported. Here we discuss the potential importance that these newly discovered transport systems could have in determining the actions of melatonin, particularly in the mitochondria. We also argue the relative importance of passive diffusion vs active transport in different parts of the cell.

  13. Deterministic transport in ratchets

    NASA Astrophysics Data System (ADS)

    Sarmiento, Antonio; Larralde, Hernán

    1999-05-01

    We present the deterministic transport properties of driven overdamped particles in a simple piecewise-linear ratchet potential. We consider the effects on the stationary current due to local spatial asymmetry, time asymmetry in the driving force, and we include the possibility of a global spatial asymmetry. We present an extremely simple scheme for evaluating the current that is established on the ratchet within an ``adiabatic'' approximation, and compare the results with exact numerical integration of the process.

  14. Transportation Systems Center

    SciTech Connect

    Greer, G.S.

    1992-07-01

    The Transportation Systems Center at Sandia Laboratory performs research, development, and implementation of technologies that enhance the safe movement of people, goods, and information. Our focus is on systems engineering. However, we realize that to understand the puzzle, you must also understand the pieces. This brochure describes some of the activities currently underway at the Center and presents the breadth and depth of our capabilities. Please contact the noted, individuals for more, information.

  15. Space Shuttle Debris Transport

    NASA Technical Reports Server (NTRS)

    Gomez, Reynaldo J., III

    2010-01-01

    This slide presentation reviews the assessment of debris damage to the Space Shuttle, and the use of computation to assist in the space shuttle applications. The presentation reviews the sources of debris, a mechanism for determining the probability of damaging debris impacting the shuttle, tools used, eliminating potential damaging debris sources, the use of computation to assess while inflight damage, and a chart showing the applications that have been used on increasingly powerful computers simulate the shuttle and the debris transport.

  16. Heat transport system

    DOEpatents

    Pierce, Bill L.

    1978-01-01

    A heat transport system of small size which can be operated in any orientation consists of a coolant loop containing a vaporizable liquid as working fluid and includes in series a vaporizer, a condenser and two one-way valves and a pressurizer connected to the loop between the two valves. The pressurizer may be divided into two chambers by a flexible diaphragm, an inert gas in one chamber acting as a pneumatic spring for the system.

  17. Retrograde Transportation (RETRO II)

    DTIC Science & Technology

    1990-01-01

    as Estimation of FY 86 Workloads for Continental United States (CONUS) Wholesale Logistics Base (ESTIMATE-86), have provided estimates as to what...the Army PROGRAM I PROJ-T f TASK WORK UNIT Washington, D.C. 20310-1718 ELEMENTNOI NO. NO. ACCESSION NO 11. TITLE (InWlude Security Clauificat id...processAutilized for determining requirements for military transportation truck units within current force structure models. THE STUDYSPONSOR was the

  18. 2002 Industry Study: Transportation

    DTIC Science & Technology

    2002-01-01

    Freightliner and Peterbilt laid off thousands of workers as production of heavy rigs plummeted from a record 262,000 in 1999 to an estimated 120,000 for...million commercial trucks and buses, 190 million private automobiles, 1.5 million railroad freight and passenger cars and 7,600 certified air carrier...carrier sector continues to be the dominant mode of freight 7 transportation in America and has been since the early 1960s. The trucking sector

  19. Space Transportation Main Engine

    NASA Technical Reports Server (NTRS)

    Monk, Jan C.

    1992-01-01

    The topics are presented in viewgraph form and include the following: Space Transportation Main Engine (STME) definition, design philosophy, robust design, maximum design condition, casting vs. machined and welded forgings, operability considerations, high reliability design philosophy, engine reliability enhancement, low cost design philosophy, engine systems requirements, STME schematic, fuel turbopump, liquid oxygen turbopump, main injector, and gas generator. The major engine components of the STME and the Space Shuttle Main Engine are compared.

  20. Expedition 8 Soyuz Transport

    NASA Image and Video Library

    2003-10-16

    A Soyuz TMA-3 spacecraft and its booster rocket is transported on a rail car to the launch pad at the Baikonur Cosmodrome, Kazakhstan on Thursday, Oct. 16, 2003 in preparation for liftoff Oct. 18 to carry Expedition 8 Commander and NASA Science Officer Michael Foale, Expedition 8 Soyuz Commander Alexander Kaleri and European Space Agency astronaut Pedro Duque of Spain to the International Space Station. Photo Credit (NASA/Bill Ingalls)