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604 results on '"The University of Alabama in Huntsville"'

1. CHASER: an innovative satellite mission concept to measure the effects of aerosols on clouds and climate

Author

University of Michigan, Massachusetts Institute of Technology, Hebrew University of Jerusalem, NASA Glenn Research Center, Freie Universität Berlin, Max-Planck-Institut für Chemie, NASA Marshall Space Flight Center, Deutsches Zentrum für Luft- und Raumfahrt (DLR), University of Oxford, University of Alabama in Huntsville, Orbital Sciences Corporation, University of Miami, Max-Planck-Institut für Meteorologie, Universität Leipzig, University of Paris VI, Universität Heidelberg, Rennó, Nilton O., Williams, Earle, Rosenfeld, Daniel, Fischer, David G., Fischer, Jürgen, Kremic, Tibor, Agrawal, Arun, Andreae, Meinrat O., Bierbaum, Rosina, Blakeslee, Richard, Boerner, Anko, Bowles, Neil, Christian, Hugh, Cox, Ann, Dunion, Jason, Horvath, Akos, Huang, Xianglei, Khain, Alexander, Kinne, Stefan, Lemos, Maria C., Penner, Joyce E., Pöschl, Ulrich, Quaas, Johannes, Seran, Elena, Stevens, Bjorn, Walati, Thomas, Wagner, Thomas, University of Michigan, Massachusetts Institute of Technology, Hebrew University of Jerusalem, NASA Glenn Research Center, Freie Universität Berlin, Max-Planck-Institut für Chemie, NASA Marshall Space Flight Center, Deutsches Zentrum für Luft- und Raumfahrt (DLR), University of Oxford, University of Alabama in Huntsville, Orbital Sciences Corporation, University of Miami, Max-Planck-Institut für Meteorologie, Universität Leipzig, University of Paris VI, Universität Heidelberg, Rennó, Nilton O., Williams, Earle, Rosenfeld, Daniel, Fischer, David G., Fischer, Jürgen, Kremic, Tibor, Agrawal, Arun, Andreae, Meinrat O., Bierbaum, Rosina, Blakeslee, Richard, Boerner, Anko, Bowles, Neil, Christian, Hugh, Cox, Ann, Dunion, Jason, Horvath, Akos, Huang, Xianglei, Khain, Alexander, Kinne, Stefan, Lemos, Maria C., Penner, Joyce E., Pöschl, Ulrich, Quaas, Johannes, Seran, Elena, Stevens, Bjorn, Walati, Thomas, and Wagner, Thomas

Abstract

The formation of cloud droplets on aerosol particles, technically known as the activation of cloud condensation nuclei (CCN), is the fundamental process driving the interactions of aerosols with clouds and precipitation. Knowledge of these interactions is foundational to our understanding of weather and climate. The Intergovernmental Panel on Climate Change (IPCC) and the Decadal Survey (NRC 2007) indicate that the uncertainty in how clouds adjust to aerosol perturbations dominates the uncertainty in the overall quantification of the radiative forcing attributable to human activities. The Clouds, Hazards, and Aerosols Survey for Earth Researchers (CHASER) satellite mission concept responds to the IPCC and Decadal Survey concerns by studying the activation of CCN and their interactions with clouds and storms. The CHASER satellite mission was developed to remotely sense quantities necessary for determining the interactions of aerosols with clouds and storms. The links between the Decadal Survey recommendations and the CHASER goals, science objectives, measurements, and instruments are described in Table 1. Measurements by current satellites allow a rough determination of profiles of cloud particle size but not of the activated CCN that seed them. CHASER will use an innovative technique (Freud et al. 2011; Freud and Rosenfeld 2012; Rosenfeld et al. 2012) and high-heritage (flown in a previous spaceflight mission) instruments to produce satellite-based remotely sensed observations of activated CCN and the properties of the clouds associated with them. CHASER will estimate updraft velocities at cloud base to calculate the number density of activated CCN as a function of the water vapor supersaturation. CHASER will determine the CCN concentration and cloud thermodynamic forcing (i.e., forcing caused by changes in the temperature and humidity of the boundary layer air) simultaneously, allowing their effects to be distinguished. Changes in the behavior of a group of weather

Published
2015

2. A far ultraviolet imager for the International Solar-Terrestrial Physics Mission

Author

University of Michigan, Ann Arbor, MI, USA, JPL, Pasadena, CA, USA, University of Washington, Seattle, WA, USA, Payload Projects Office, Marshall Space Flight Center, 35812, Huntsville, Al, USA, Optical Aeronomy Laboratory, University of Alabama in Huntsville, 35899, Huntsville, AL, USA, Optical E.T.C., Inc., 35801, Huntsville, AL, USA, LaTrobe University, La Trobe, Australia, Space Science Laboratory, Marshall Space Flight Center, 35812, Huntsville, AL, USA, Ann Arbor, Banks, P., Johnson, R.B., Torr, Marsha R., Torr, D.G., Zukic, M., Ajello, J.M., Clark, K., Cole, K., Keffer, C., Parks, G., Tsurutani, B.T., Spann, J., University of Michigan, Ann Arbor, MI, USA, JPL, Pasadena, CA, USA, University of Washington, Seattle, WA, USA, Payload Projects Office, Marshall Space Flight Center, 35812, Huntsville, Al, USA, Optical Aeronomy Laboratory, University of Alabama in Huntsville, 35899, Huntsville, AL, USA, Optical E.T.C., Inc., 35801, Huntsville, AL, USA, LaTrobe University, La Trobe, Australia, Space Science Laboratory, Marshall Space Flight Center, 35812, Huntsville, AL, USA, Ann Arbor, Banks, P., Johnson, R.B., Torr, Marsha R., Torr, D.G., Zukic, M., Ajello, J.M., Clark, K., Cole, K., Keffer, C., Parks, G., Tsurutani, B.T., and Spann, J.

Abstract

The aurorae are the result of collisions with the atmosphere of energetic particles that have their origin in the solar wind, and reach the atmosphere after having undergone varying degrees of acceleration and redistribution within the Earth's magnetosphere. The global scale phenomenon represented by the aurorae therefore contains considerable information concerning the solar-terrestrial connection. For example, by correctly measuring specific auroral emissions, and with the aid of comprehensive models of the region, we can infer the total energy flux entering the atmosphere and the average energy of the particles causing these emissions. Furthermore, from these auroral emissions we can determine the ionospheric conductances that are part of the closing of the magnetospheric currents through the ionosphere, and from these we can in turn obtain the electric potentials and convective patterns that are an essential element to our understanding of the global magnetosphere-ionosphere-thermosphere-mesosphere. Simultaneously acquired images of the auroral oval and polar cap not only yield the temporal and spatial morphology from which we can infer activity indices, but in conjunction with simultaneous measurements made on spacecraft at other locations within the magnetosphere, allow us to map the various parts of the oval back to their source regions in the magnetosphere. This paper describes the Ultraviolet Imager for the Global Geospace Sciences portion of the International Solar-Terrestrial Physics program. The instrument operates in the far ultraviolet (FUV) and is capable of imaging the auroral oval regardless of whether it is sunlit or in darkness. The instrument has an 8° circular field of view and is located on a despun platform which permits simultaneous imaging of the entire oval for at least 9 hours of every 18 hour orbit. The three mirror, unobscured aperture, optical system (f /2.9) provides excellent imaging over this full field of view, yielding a per pixel

Published
2006

3. Satellite observations of new particle and field signatures associated with SAR arc field lines at magnetospheric heights

Author

Space Physics Research Laboratory, University of Michigan, Ann Arbor, MI 48109, U.S.A., University of Iowa, Iowa City, IA 52242, U.S.A., University of Alabama in Huntsville, Huntsville, AL 35899, U.S.A., NASA/Marshall Space Flight Center, Huntsville, AL 35812, U.S.A., NASA/Goddard Space Flight Center, Greenbelt, MD 20771, U.S.A., Southwest Research Institute, P.O. Drawer 28510, San Antonio, TX 78284, U.S.A., Kozyra, Janet U., Cravens, Tom E., Nagy, Andrew F., Gurnett, D.A., Huff, R.L., Comfort, R.H., Waite, Jr, J.H., Brace, Larry H., Winningham, J.D., Space Physics Research Laboratory, University of Michigan, Ann Arbor, MI 48109, U.S.A., University of Iowa, Iowa City, IA 52242, U.S.A., University of Alabama in Huntsville, Huntsville, AL 35899, U.S.A., NASA/Marshall Space Flight Center, Huntsville, AL 35812, U.S.A., NASA/Goddard Space Flight Center, Greenbelt, MD 20771, U.S.A., Southwest Research Institute, P.O. Drawer 28510, San Antonio, TX 78284, U.S.A., Kozyra, Janet U., Cravens, Tom E., Nagy, Andrew F., Gurnett, D.A., Huff, R.L., Comfort, R.H., Waite, Jr, J.H., Brace, Larry H., and Winningham, J.D.

Abstract

Enhancements in thermal ion densities, an oxygen dominated ring current at energies below 17 kev, and invariant latitude-limited bands of intense ELF hiss have been discovered on Stable Auroral Red (SAR) arc field lines at magnetospheric heights. These new signatures were revealed by an examination of 31 coordinated data sets taken simultaneously at magnetospheric and ionospheric heights by the DE-1 and -2 satellites during SAR arc traversals within the period September 1981 through April 1982. Data sets from DE-2, for the first time, provide information on the location of a SAR arc (determined by the F region electron temperature enhancement) during the nearly simultaneous passage of these field lines by DE-1 in the magnetosphere. These new high altitude signatures are examined in the context of possible magnetospheric SAR arc energy source mechanisms.

Published
2006

4. Non negligible impacts of clean air regulations on the reduction of tropospheric NO2 over East China during the COVID 19 pandemic observed by OMI and TROPOMI

Author

Huang, Guanyu, Spelman College (Author), Ponder, Reyla, Spelman College and Georgia Institute of Technology (Author), Bond, Amber, Spelman College (Author), Brim, Hailey, Spelman College (Author), Temeng, Akua, Spelman College (Author), Naeger, Aaron R., University of Alabama in Huntsville (Author), Zhu, Lei, Southern University of Science and Technology (Author), Huang, Guanyu, Spelman College (Author), Ponder, Reyla, Spelman College and Georgia Institute of Technology (Author), Bond, Amber, Spelman College (Author), Brim, Hailey, Spelman College (Author), Temeng, Akua, Spelman College (Author), Naeger, Aaron R., University of Alabama in Huntsville (Author), and Zhu, Lei, Southern University of Science and Technology (Author)

Abstract

We studied the impact of COVID-19 (coronavirus disease 2019) lockdown on the air quality over the Atlanta area using satellite and ground-based observations, meteorological reanalysis data and traffic information. Unlike other cities, we found the air quality has improved slightly over the Atlanta area during the 2020 COVID-19 lockdown period (March 14-April 30, 2020), compared to the analogous period of 2019 (March 14-April 30, 2019). Ground NO2 concentrations have decreased slightly 10.8% and 8.2% over the near-road (NR) and urban ambient (UA) stations, respectively. Tropospheric NO2 columns have reduced 13%-49% over the Atlanta area from space-borne observations of TROPOspheric Monitoring Instrument (TROPOMI). Ground ozone and PM2.5 have decreased 15.7% an ~5%, respectively. This slight air quality improvement is primarily caused by the reduced human activities, as COVID-19 lockdowns have reduced ~50% human activities, measured by traffic volume. Higher wind speed and precipitations also make the meteorological conditions favorable to this slight air quality improvement. We have not found a significant improvement in Atlanta amid the lockdown when human activities have reduced ~50%. Further studies are needed to understand the impacts of reduced human activities on atmospheric chemistry. We also found TROPOMI and ground measurements have disagreements on NO2 reductions, as collocated TROPOMI observations revealed ~23% and ~21% reductions of tropospheric NO2 columns over NR and UA stations, respectively. Several factors may explain this disagreement: First, tropospheric NO2 columns and ground NO2 concentrations are not necessarily the same, although they are highly correlated in the afternoon; Second, meteorological conditions may have different impacts on TROPMI and ground measurements. Third, TROPOMI may underestimate tropospheric NO2 due to uncertainties from air mass factors. Fourth, the uncertainties of chemiluminescence NO2 measurements used by ground statio

5. Transportation engineering advancement and mentoring program : phase I.

Author

Leonard, Kathleen M., University of Alabama in Huntsville. Civil and Environmental Engineering Department, Leonard, Kathleen M., and University of Alabama in Huntsville. Civil and Environmental Engineering Department

Abstract

UTCA 09306, The numbers of female and minority students enrolled in engineering schools are increasing slowly; however, there are still, relatively small percentages drawn to the field of transportation civil engineering. As a consequence, there is a need to educate, young people about the profession to encourage individuals from under-represented groups to appreciate the contributions of, engineers to society and encourage them to become civil engineers. This summer institute project consisted of bringing middleschool, students, after recommendations by their teachers, to the University of Alabama in Huntsville campus to learn about, engineering as a career and to experience a variety of transportation-engineering design topics. The participants gained knowledge, about the role of engineers in society and learned how engineers use their knowledge in design applications. An additional, program was held this year in which the instructors visited local schools during engineers’ week to promote the design build, challenge held at the university in the fall. UAH female faulty members and professionals from the Society of Women Engineers, acted as team mentors.

6. Structural response of near surface mounted CFRP strengthened reinforced concrete bridge deck overhang.

Author

California. Department of Transportation, Pridmore, Anna B., Karbhari, Vistasp M., University of California, San Diego. Dept. of Structural Engineering, University of Alabama in Huntsville, California. Department of Transportation, Pridmore, Anna B., Karbhari, Vistasp M., University of California, San Diego. Dept. of Structural Engineering, and University of Alabama in Huntsville

Abstract

59A0630, This report presents the results from an experimental investigation which explores the change in structural response due to the addition of near-surface-mounted (NSM) carbon fiber reinforced polymer (CFRP) reinforcement for increasing the capacity of the edge region of a reinforced concrete bridge deck. The motivation for rehabilitating bridge deck overhangs using NSM reinforcement is to increase the load carrying capacity of the region so that the overhang can accommodate the larger than designed for loads caused by the installation of sound barrier walls onto the edges of the bridge deck. The experimental testing of an as-built reinforced concrete specimen without FRP was used as the baseline test to evaluate the effectiveness of the NSM CFRP strengthening scheme. Details regarding the capacity calculations, experimental setup, testing protocol and experimental results for the as-built specimen and FRP rehabilitated specimen are discussed in this report. This report also presents the NSM CFRP strengthening design options examined for achieving the desired capacity increase and evaluates the change in structural response of the rehabilitated system as compared to the as-built test specimen.

7. Development of multimedia resource and short courses for LRFD design.

Author

Alabama. Department of Transportation, Toutanji, Houssam, University of Alabama in Huntsville. Civil and Environmental Engineering Department, Alabama. Department of Transportation, Toutanji, Houssam, and University of Alabama in Huntsville. Civil and Environmental Engineering Department

Abstract

Research project no. 930-703, Multimedia technology is an essential instrument in the development of graduate engineers. This, multimedia package provides an exclusive background and an in-depth understanding of the new, technological advances in the design of concrete, steel and prestressed concrete bridges. It gives, guidelines and step-by-step instructions for the design of different types of bridges using the, LRFD specifications. It also includes an introduction of comparing three rating procedures, (ASR, LFR, and LRFR). One of the advantages of the package is that it can be conveniently, updated and modified to add future changes and procedures necessary for today’s structural, demand., The LRFD specifications were created with a conservative point of view, applying almost, exclusively the limit states of strength. It is consistent with other major bridge codes adopted or, being adopted in many other countries such as Canada and the European countries. Because of, this many states throughout the United States have changed their specifications and are currently, implementing LRFD. It incorporates deep analysis and design methods with different kinds of, loads and resistance factors, which are based on the known variability of applied loads and the, material properties. This multimedia package includes the basis in which an engineer can design, a concrete bridge using LRFD specifications. It includes some PDF documents containing, explanatory examples and an overview of the strategic development of this structural code., This project has a main focus to be a self-training tool for inexperienced engineers who are, interested in learning about the implementation of LRFD specifications in the design of concrete, bridges. It is a valuable tool because it contains procedures and specifications for each possible, situation together with detailed examples and illustrations. This package is a time saving, userfriendly, reliable way of learning.

8. Methods for forecasting freight in uncertainty : time series analysis of multiple factors.

Author

Alabama. Department of Transportation, Farrington, Phillip A., University of Alabama in Huntsville, Alabama. Department of Transportation, Farrington, Phillip A., and University of Alabama in Huntsville

Abstract

The main goal of this research was to analyze and more accurately model freight movement in, Alabama. Ultimately, the goal of this project was to provide an overall approach to the, integration of accurate freight models into transportation plans and models in Alabama., The first step in the process was to identify the dependent variable and collect the data necessary, to develop the models. Initially, Truck Vehicle Miles Traveled (VMT) was the preferred, dependent variable however, data collection revealed that the available VMT was not, particularly accurate since it is derived from VMT data for all vehicles and there was no, validated method for estimating the percentage of trucks in any one year. Therefore, the research, team determined that annual Diesel Tax collections would be a good surrogate for Truck VMT., The Diesel Tax collections were used to estimate the Diesel Gallons Sold each year by dividing, by the tax rate for that year. This variable, Diesel Gallons Sold (DGS), has the advantage that it, could be used to estimate annual truck volumes based on estimate mileage performance for, trucks. Thus, DGS was chosen as the dependent variable for this study.

9. Effectively using the QRFM to model truck trips in medium-sized urban communities.

Author

University Transportation Center for Alabama, Anderson, Michael, Dondapati, Mary Catherine, Harris, Gregory, University of Alabama in Huntsville. Civil and Environmental Engineering Department, University Transportation Center for Alabama, Anderson, Michael, Dondapati, Mary Catherine, Harris, Gregory, and University of Alabama in Huntsville. Civil and Environmental Engineering Department

Abstract

This report analyzes the effectiveness of applying the Quick Response Freight Manual (QRFM) to model freight, transportation. Typically freight transportation is modeled indirectly or as an after-thought. Increasing freight, volumes, coupled with cost-saving strategies such as just-in-time delivery systems, require that transportation, policymakers analyze infrastructure needs and make investment decisions that explicitly include freight volumes as, a component. This paper contains a case study using a travel model for a medium-sized urban area and the QRFM, trip-generation and distribution methodology to provide a framework for freight planning that can be used to, improve resource-allocation decisions

10. Effect of Current Sheets on the Solar Wind Magnetic Field Power Spectrum from the Ulysses Observation: From Kraichnan to Kolmogorov Scaling

Author

Qin, G [Department of Physics and CSPAR, University of Alabama in Huntsville, Alabama 35899 (United States); CAS Key Laboratory of Basic Plasma Physics, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China); CSPAR, University of Alabama in Huntsville, Alabama 35899 (United States); State Key Laboratory of SpaceWeather, Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190 (China)]

Published
2011
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11. Detection of small magnetic flux ropes from the third and fourth Parker Solar Probe encounters

Author

T. Dudok de Wit, N. Raouafi, Yu Chen, Stuart D. Bale, Davin Larson, John W. Bonnell, Kelly E. Korreck, Katja Klein, Peter Harvey, Robert J. MacDowall, Anthony W. Case, Keith Goetz, Lingling Zhao, Roberto Livi, David M. Malaspina, Phyllis Whittlesey, Qiang Hu, Michael Stevens, Gary P. Zank, Marc Pulupa, Jia Huang, Justin C. Kasper, M. Nakanotani, Laxman Adhikari, Daniele Telloni, Center for Space Plasma and Aeronomic Research [Huntsville] (CSPAR), University of Alabama in Huntsville (UAH), The University of Alabama in Huntsville, Space Sciences Laboratory [Berkeley] (SSL), University of California [Berkeley], University of California-University of California, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National d’Études Spatiales [Paris] (CNES)

Subjects
FOS: Physical sciences, Context (language use), Astrophysics, 01 natural sciences, Physics - Space Physics, Magnetic helicity, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Physics, Spacecraft, 010308 nuclear & particles physics, business.industry, Turbulence, Astronomy and Astrophysics, Magnetic flux, Space Physics (physics.space-ph), Solar wind, Astrophysics - Solar and Stellar Astrophysics, [SDU]Sciences of the Universe [physics], Space and Planetary Science, Physics::Space Physics, Heliospheric current sheet, Astrophysics::Earth and Planetary Astrophysics, business, Rope
Abstract

Context. Aims. We systematically search for magnetic flux rope structures in the solar wind to within the closest distance to the Sun of ~0.13 AU, using data from the third and fourth orbits of the Parker Solar Probe. Methods. We extended our previous magnetic helicity-based technique of identifying magnetic flux rope structures. The method was improved upon to incorporate the azimuthal flow, which becomes larger as the spacecraft approaches the Sun. Results. A total of 21 and 34 magnetic flux ropes are identified during the third (21-day period) and fourth (17-day period) orbits of the Parker Solar Probe, respectively. We provide a statistical analysis of the identified structures, including their relation to the streamer belt and heliospheric current sheet crossing.

Published
2020
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12. Convergent evolution and horizontal gene transfer in Arctic Ocean microalgae

Author

Richard G Dorrell, Alan Kuo, Zoltan Füssy, Elisabeth H Richardson, Asaf Salamov, Nikola Zarevski, Nastasia J Freyria, Federico M Ibarbalz, Jerry Jenkins, Juan Jose Pierella Karlusich, Andrei Stecca Steindorff, Robyn E Edgar, Lori Handley, Kathleen Lail, Anna Lipzen, Vincent Lombard, John McFarlane, Charlotte Nef, Anna MG Novák Vanclová, Yi Peng, Chris Plott, Marianne Potvin, Fabio Rocha Jimenez Vieira, Kerrie Barry, Colomban de Vargas, Bernard Henrissat, Eric Pelletier, Jeremy Schmutz, Patrick Wincker, Joel B Dacks, Chris Bowler, Igor V Grigoriev, Connie Lovejoy, Institut de biologie de l'ENS Paris (IBENS), Département de Biologie - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Lawrence Berkeley National Laboratory [Berkeley] (LBNL), Charles University [Prague] (CU), University of Alberta, Université Laval [Québec] (ULaval), HudsonAlpha Genome Sequencing Center, University of Alabama in Huntsville (UAH), Architecture et fonction des macromolécules biologiques (AFMB), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Station biologique de Roscoff (SBR), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), King Abdulaziz University, Genoscope - Centre national de séquençage [Evry] (GENOSCOPE), Université Paris-Saclay-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), ANR-21-CE02-0014,PanArctica,Caractérisation phylogénétique, écologique et physiologique de le pan-génome des algues Arctiques(2021), and ANR-22-ERCS-0018,ChloroMosaic,Caractérisation moléculaire du réussite environnemental de la chloroplaste secondaire rouge(2022)

Subjects
Ecology, Bacteria, Arctic Regions, Health, Toxicology and Mutagenesis, Oceans and Seas, Gene Transfer, Plant Science, [SDV.BID]Life Sciences [q-bio]/Biodiversity, Biochemistry, Genetics and Molecular Biology (miscellaneous), Horizontal, [SDV.MP]Life Sciences [q-bio]/Microbiology and Parasitology, Microalgae, Ice Cover, Life Below Water
Abstract

Microbial communities in the world ocean are affected strongly by oceanic circulation, creating characteristic marine biomes. The high connectivity of most of the ocean makes it difficult to disentangle selective retention of colonizing genotypes (with traits suited to biome specific conditions) from evolutionary selection, which would act on founder genotypes over time. The Arctic Ocean is exceptional with limited exchange with other oceans and ice covered since the last ice age. To test whether Arctic microalgal lineages evolved apart from algae in the global ocean, we sequenced four lineages of microalgae isolated from Arctic waters and sea ice. Here we show convergent evolution and highlight geographically limited HGT as an ecological adaptive force in the form of PFAM complements and horizontal acquisition of key adaptive genes. Notably, ice-binding proteins were acquired and horizontally transferred among Arctic strains. A comparison withTaraOceans metagenomes and metatranscriptomes confirmed mostly Arctic distributions of these IBPs. The phylogeny of Arctic-specific genes indicated that these events were independent of bacterial-sourced HGTs in Antarctic Southern Ocean microalgae.

Published
2022
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13. A Batteryless Series Hybrid Electric Vehicle Control

Author

Sébastien Rouquet, Malek Ghanes, Jean-Pierre Barbot, Yuri B. Shtessel, Ludovic Merienne, École Centrale de Nantes (Nantes Univ - ECN), Nantes Université (Nantes Univ), Laboratoire des Sciences du Numérique de Nantes (LS2N), Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-École Centrale de Nantes (Nantes Univ - ECN), Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Ecole Nationale Supérieure de l'Electronique et de ses Applications (ENSEA), Department of Electrical and Computer Engineering [Huntsville], University of Alabama in Huntsville (UAH), Technocentre Renault [Guyancourt], and RENAULT

Subjects
Control and Systems Engineering, [SPI.NRJ]Engineering Sciences [physics]/Electric power, Electrical and Electronic Engineering, [SPI.AUTO]Engineering Sciences [physics]/Automatic
Abstract

International audience

Published
2022
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19. Magnetic field generation in a jet-sheath plasma via the kinetic Kelvin-Helmholtz instability

Author

Mikhail V. Medvedev, Åke Nordlund, P. E. Hardee, Jacek Niemiec, Dieter H. Hartmann, K. W. Min, Ioana Duţan, Ken-Ichi Nishikawa, E. J. Choi, Bing Zhang, Helene Sol, Jacob Trier Frederiksen, Martin Pohl, Yosuke Mizuno, National Space Science and Technology Center (NSSTC), NASA Marshall Space Flight Center (MSFC)-University of Alabama in Huntsville (UAH), Chungnam National University (CNU), University of Copenhagen = Københavns Universitet (KU), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Matériaux, ingénierie et science [Villeurbanne] (MATEIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), University of Alabama in Huntsville (UAH)-NASA Marshall Space Flight Center (MSFC), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)

Subjects
Atmospheric Science, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Kinetic energy, 01 natural sciences, Instability, and astronomy (Energetic particles), Electric field, 0103 physical sciences, Earth and Planetary Sciences (miscellaneous), lcsh:Science, 010303 astronomy & astrophysics, Saturation (magnetic), ComputingMilieux_MISCELLANEOUS, Physics, Solar physics, [PHYS]Physics [physics], High Energy Astrophysical Phenomena (astro-ph.HE), astrophysics, 010308 nuclear & particles physics, lcsh:QC801-809, Institut für Physik und Astronomie, Geology, Astronomy and Astrophysics, Plasma, Mechanics, lcsh:QC1-999, Magnetic field, Particle acceleration, Transverse plane, lcsh:Geophysics. Cosmic physics, Classical mechanics, Space and Planetary Science, lcsh:Q, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], lcsh:Physics
Abstract

We have investigated generation of magnetic fields associated with velocity shear between an unmagnetized relativistic jet and an unmagnetized sheath plasma. We have examined the strong magnetic fields generated by kinetic shear (Kelvin-Helmholtz) instabilities. Compared to the previous studies using counter-streaming performed by Alves et al. (2012), the structure of KKHI of our jet-sheath configuration is slightly different even for the global evolution of the strong transverse magnetic field. In our simulations the major components of growing modes are the electric field $E_{\rm z}$ and the magnetic field $B_{\rm y}$. After the $B_{\rm y}$ component is excited, an induced electric field $E_{\rm x}$ becomes significant. However, other field components remain small. We find that the structure and growth rate of KKHI with mass ratios $m_{\rm i}/m_{\rm e} = 1836$ and $m_{\rm i}/m_{\rm e} = 20$ are similar. In our simulations saturation in the nonlinear stage is not as clear as in counter-streaming cases. The growth rate for a mildly-relativistic jet case ($\gamma_{\rm j} = 1.5$) is larger than for a relativistic jet case ($\gamma_{\rm j} = 15$)., Comment: 6 pages, 6 figures, presented at Dynamical processes in space plasmas II, Isradinamic 2012, in press, ANGEO. arXiv admin note: text overlap with arXiv:1303.2569

Published
2013
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20. Mutations in the neverland gene turned Drosophila pachea into an obligate specialist species

Author

Andrew G. Clark, Virginie Orgogozo, Luciano M. Matzkin, Michael Lang, Takuji Yoshiyama-Yanagawa, Emilie Guittard, Géraldine Gouppil, Sophie Murat, Ryusuke Niwa, René Lafont, Catherine Blais, Hiroshi Kataoka, Chantal Dauphin-Villemant, CNRS UMR7592, Université Paris Diderot, Sorbonne Paris Cité, Institut Jacques Monod, 15 rue Hélène Brion, 75205 Paris cedex 13, France., Université Pierre et Marie Curie - Paris 6 (UPMC), Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA., CNRS UMR7592, Université Paris Diderot, Sorbonne Paris Cité, Institut Jacques Monod, 15 rue Hélène Brion, 75205 Paris cedex 13, France, Department of Biological Sciences, University of Alabama in Huntsville, 301 Sparkman Drive, Huntsville, AL 35899, USA., Graduate School of Life and Environmental Sciences, University of Tsukuba, Tennoudai 1-1-1, Tsukuba, Ibaraki 305-8572, Japan., Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan., Institut Jacques Monod (IJM (UMR_7592)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Department of Molecular Biology and Genetics, Cornell University, Cornell University [New York], Department of Biological Sciences, University of Alabama in Huntsville, University of Alabama in Huntsville (UAH), Graduate School of Life and Environmental Sciences, University of Tsukuba, Université de Tsukuba = University of Tsukuba, Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, The University of Tokyo (UTokyo), CNRS ATIP-AVENIR, French Foreign Ministry postdoctoral fellowship, NIH ( AI064950), Japan-France Bilateral Cooperating Program from the Japan Society for the Promotion of Science (JSPS), NSF (DEB-1020009), NSF, JSPS, Ministry of Education, Culture, Sports, Science and Technology in Japan, Amylin Endowment Évolution des drosophiles, Cornell University, University of Tsukuba, The University of Tokyo, Departement of Molecular Biology and Genetics [CALS], College of Agriculture and Life Sciences [Cornell University] (CALS), and Cornell University [New York]-Cornell University [New York]

Subjects
0106 biological sciences, Cactaceae, MESH: Drosophila, Protein Conformation, MESH: Selection, Genetic, MESH: Amino Acid Sequence, Generalist and specialist species, medicine.disease_cause, 01 natural sciences, MESH: Protein Conformation, MESH: Cholesterol, Drosophila Proteins, MESH: Animals, [SDV.BDD]Life Sciences [q-bio]/Development Biology, MESH: Cactaceae, ComputingMilieux_MISCELLANEOUS, Conserved Sequence, 0303 health sciences, Mutation, Multidisciplinary, MESH: Conserved Sequence, biology, [SDV.BID.EVO]Life Sciences [q-bio]/Biodiversity/Populations and Evolution [q-bio.PE], MESH: Oxygenases, Cholesterol, Oxygenases, Drosophila, RNA Interference, Drosophila Protein, MESH: Mutation, Food Chain, MESH: Drosophila Proteins, MESH: RNA Interference, Molecular Sequence Data, Zoology, 010603 evolutionary biology, Article, 03 medical and health sciences, Dehydrocholesterols, Species Specificity, medicine, MESH: Species Specificity, Animals, MESH: Dehydrocholesterols, Amino Acid Sequence, MESH: Food Chain, Selection, Genetic, Gene, 030304 developmental biology, Ecological niche, MESH: Molecular Sequence Data, Obligate, Host (biology), biology.organism_classification, [SDV.GEN.GA]Life Sciences [q-bio]/Genetics/Animal genetics, Evolutionary biology, [SDV.EE.IEO]Life Sciences [q-bio]/Ecology, environment/Symbiosis
Abstract

Limiting Your Options Many species are dependent on specific resources that may limit their range of hosts to that of a few or even a single species. The restriction of the fly Drosophila pachea to senita cactus is a classic case of an ecological specialization. Lang et al. (p. 1658 ) reveal how multiple amino acid substitutions in the neverland gene have rendered D. pachea dependent upon the lathosterol of the senita cactus. Thus, relatively few genetic changes can play a large role in determining a species' ecological niche.

Published
2012
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21. ERP-Driven Performance Changes and Process Isomorphism

Author

Andrea Masini, Haldemann, Antoine, Jatinder N. D. Gupta (The University of Alabama in Huntsville, USA), Sushil Sharma (Ball State University, USA), Mohammad A. Rashid (Massey University, New Zealand), Department of Management Science and Operations, London Business School, Jatinder N. D. Gupta (The University of Alabama in Huntsville, USA), Sushil Sharma (Ball State University, Mohammad A. Rashid (Massey University, and New Zealand)

Subjects
Window of opportunity, [SHS.GESTION.MAN-OP] Humanities and Social Sciences/Business administration/domain_shs.gestion.man-op, Short run, Competitor analysis, Business value, [SHS.GESTION.MAN-OP]Humanities and Social Sciences/Business administration/domain_shs.gestion.man-op, Profit (economics), Value of information, Panel analysis, Profitability index, Isomorphism, Business, Marketing, Industrial organization, ERP
Abstract

http://www.igi-global.com/bookstore/Chapter.aspx?TitleId=20275; After observing that the pervasiveness of IT may soon render it strategically irrelevant, management scholars have recently questioned the value of information technology. This chapter challenges the above view, contends that ERP investments may contribute to the achievement of improved business performance, and examines the conditions under which this contribution occurs. The panel analysis of a sample of SAP R/3 adopters provides several insights. First, it suggests that the ERP exerts a generalized positive impact on both productivity and profitability. Second, the results confirm that the widespread diffusion of best practices embedded in the software may limit the ability of firms to use ERP to effectively differentiate from competitors. However, they also suggest that, whilst in the long run the pervasive diffusion of standardized software may decrease its strategic value, in the short run early ERP adopters can profit from a window of opportunity to obtain above average returns.

Published
2009

22. Basin-scale wind transport during the MILAGRO field campaign and comparison to climatology using cluster analysis

Author

Foy, B., Fast, J. D., Paech, S. J., Phillips, D., Walters, J. T., Coulter, R. L., Martin, T. J., Pekour, M. S., Shaw, W. J., Kastendeuch, Marley, N. A., Retama, A., Molina, L. T., Molina Center for the Energy and the Environment (MCE2), Department of Earth and Atmospheric Sciences [Saint Louis], Saint Louis University (SLU), Pacific Northwest National Laboratory (PNNL), National Space Science and Technology Center (NSSTC), NASA Marshall Space Flight Center (MSFC)-University of Alabama in Huntsville (UAH), Argonne National Laboratory [Lemont] (ANL), Centre de géochimie de la surface (CGS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Department of Chemistry, Secretaría del Medio Ambiente, Department of Earth, Atmospheric and Planetary Sciences [MIT, Cambridge] (EAPS), Massachusetts Institute of Technology (MIT), University of Alabama in Huntsville (UAH)-NASA Marshall Space Flight Center (MSFC), Centre National de la Recherche Scientifique (CNRS)-Université Louis Pasteur - Strasbourg I-Institut national des sciences de l'Univers (INSU - CNRS), Gobierno del Distrito Federal, and EGU, Publication

Subjects
lcsh:Chemistry, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, lcsh:QD1-999, 010504 meteorology & atmospheric sciences, [SDU.OCEAN] Sciences of the Universe [physics]/Ocean, Atmosphere, 13. Climate action, 010501 environmental sciences, 01 natural sciences, lcsh:Physics, lcsh:QC1-999, 0105 earth and related environmental sciences
Abstract

The MILAGRO field campaign was a multi-agency international collaborative project to evaluate the regional impacts of the Mexico City air pollution plume as a means of understanding urban impacts on the global climate. Mexico City lies on an elevated plateau with mountains on three sides and has complex mountain and surface-driven wind flows. This paper asks what the wind transport was in the basin during the field campaign and how representative it was of the climatology. Surface meteorology and air quality data, radiosoundings and radar wind profiler data were collected at sites in the basin and its vicinity. Cluster analysis is used to identify the dominant wind patterns both during the campaign and within the past 10 years of operational data from the warm dry season. Our analysis shows that March 2006 was representative of typical flow patterns experienced in the basin. Six episode types were identified for the basin scale circulation providing a way of interpreting atmospheric chemistry and particulate data collected during the campaign. Decoupling between surface winds and those aloft had a strong influence in leading to convection and poor air quality episodes. Hourly characterisation of wind circulation during the MILAGRO, MCMA-2003 and IMADA field campaigns will enable the comparisons of similar air pollution episodes and the evaluation of the impact of wind transport on measurements of the atmospheric chemistry taking place in the basin.

Published
2008

33. Panoramic imaging mass-spectrometer for planetary studies, Symposium sur 'Future planetary missions to be proposed in the Cosmic Vision framework'

Author

Vaisberg, O., Berthelier, Jean-Jacques, Torkar, K., Leblanc, François, Woch, J., Avanov, L., Skalski, A., Delcourt, Dominique, Smirnov, V., Koinash, G., Space Research Institute of the Russian Academy of Sciences (IKI), Russian Academy of Sciences [Moscow] (RAS), Southwest Research Institute [San Antonio] (SwRI), Centre d'étude des environnements terrestre et planétaires (CETP), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut für Weltraumforschung [Graz] (IWF), Osterreichische Akademie der Wissenschaften (ÖAW), Service d'aéronomie (SA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, National Space Science and Technology Center (NSSTC), University of Alabama in Huntsville (UAH)-NASA Marshall Space Flight Center (MSFC), Institut für Weltraumforschung = Space Research institute [Graz] (IWF), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), and NASA Marshall Space Flight Center (MSFC)-University of Alabama in Huntsville (UAH)

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Physics::Plasma Physics, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], Physics::Space Physics, Astrophysics::Earth and Planetary Astrophysics
Abstract

Plasma diagnostics can provide extremely useful information for solar system studies. Neutral and ion sputtering from the surface leads to the formation of neutral and ion exospheres with compositions that reflect the surface composition modified by ioniza- tion and transport processes around the body. Measurements of ion composition and velocity distributions provide important information about surface composition and its recycling. Plasma measurements from low altitude spacecraft and landers on plan- etary bodies without atmospheres can be used to map the surface composition, while spectrometers onboard spacecraft orbiting planets with atmosphere are used for study of planetary losses, mass-exchange with the solar wind, and the long-term evolution of their environment.To perform reliable measurements of planetary plasmas a complete 3-dimensional velocity distributions of various ion species is necessary. In addition, if fast measure- ments of the major ion species are the main goal of plasma physics studies, precise measurements of the minor ion composition are often essential to unveil important properties of the atmosphere or the surface. Therefore ion mass spectrometers for so- lar system missions require both the capability of making fast measurements of the 3D-velocity distribution of ions and high mass resolution for detailed composition studies.We describe a novel type of miniature panoramic ion mass-spectrometer suitable for making such 3-dimensional measurements of ion components with high mass resolu- tion. The feeding electron optics of our plasma analyzer (CAMERA) allows for fast measurements within an instantaneous 2π field of view, which has no gaps and can be accomplished on either stabilized or rotating spacecraft, or landers. It is followed by a time-of-flight mass-spectrometer that retains imaging capabilities of the feeding optics and provides mass-resolution M/∆M in excess of 100. Our spectrometer also provides flexible control of the energy bandwidth, mass and angular resolution, as well as high temporal resolution and UV rejection. This type of instrument is under development for BepiColombo and Phobos-Grunt missions

Published
2006

34. Panoramic imaging mass-spectrometer for planetary studies

Author

Vaisberg, O., Berthelier, Jean-Jacques, Torkar, K., Leblanc, François, Escoubet, P., Woch, J., Baumjohann, W., Avanov, L., Burch, J., Mccomas, D., Delcourt, Dominique, Wurz, P., Grishin, V., Smirnov, V., Babkin, V., Szego, K., Southwest Research Institute [San Antonio] (SwRI), Space Research Institute of the Russian Academy of Sciences (IKI), Russian Academy of Sciences [Moscow] (RAS), Centre d'étude des environnements terrestre et planétaires (CETP), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut für Weltraumforschung [Graz] (IWF), Osterreichische Akademie der Wissenschaften (ÖAW), Service d'aéronomie (SA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, National Space Science and Technology Center (NSSTC), University of Alabama in Huntsville (UAH)-NASA Marshall Space Flight Center (MSFC), Physikalisches Institut [Bern], Universität Bern [Bern], Institute for Particle and Nuclear Physics [Budapest], Wigner Research Centre for Physics [Budapest], Hungarian Academy of Sciences (MTA)-Hungarian Academy of Sciences (MTA), Institut für Weltraumforschung = Space Research institute [Graz] (IWF), Agence Spatiale Européenne = European Space Agency (ESA), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), NASA Marshall Space Flight Center (MSFC)-University of Alabama in Huntsville (UAH), Universität Bern [Bern] (UNIBE), and Cardon, Catherine

Subjects
[PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], [PHYS.ASTR.CO] Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Physics::Plasma Physics, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], [PHYS.PHYS.PHYS-PLASM-PH] Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], Physics::Space Physics, Astrophysics::Earth and Planetary Astrophysics, [SDU.ASTR] Sciences of the Universe [physics]/Astrophysics [astro-ph]
Abstract

Plasma diagnostics can provide extremely useful information for solar system studies. Neutral and ion sputtering from the surface leads to the formation of neutral and ion exospheres with compositions that reflect the surface composition modified by ionization and transport processes around the body. Measurements of ion composition and velocity distributions provide important information about surface composition and its recycling. Plasma measurements from low altitude spacecraft and landers on planetary bodies without atmospheres can be used to map the surface composition, while spectrometers onboard spacecraft orbiting planets with atmosphere are used for study of planetary losses, mass-exchange with the solar wind, and the long-term evolution of their environment. To perform reliable measurements of planetary plasmas a complete 3-dimensional velocity distributions of various ion species is necessary. In addition, if fast measurements of the major ion species are the main goal of plasma physics studies, precise measurements of the minor ion composition are often essential to unveil important properties of the atmosphere or the surface. Therefore ion mass spectrometers for solar system missions require both the capability of making fast measurements of the 3D-velocity distribution of ions and high mass resolution for detailed composition studies. We describe a novel type of miniature panoramic ion mass-spectrometer suitable for making such 3-dimensional measurements of ion components with high mass resolution. The feeding electron optics of our plasma analyzer (CAMERA) allows for fast measurements within an instantaneous 2p field of view, which has no gaps and can be accomplished on either stabilized or rotating spacecraft, or landers. It is followed by a time-of-flight mass-spectrometer that retains imaging capabilities of the feeding optics and provides mass-resolution M/ΔM in excess of 100. Our spectrometer also provides flexible control of the energy bandwidth, mass and angular resolution, as well as high temporal resolution and UV rejection. The mass of the 2p panoramic ion energy-mass-spectrometer can be made as low as 1 kg.

Published
2004

36. MAGNETIC FIELD GENERATION IN CORE-SHEATH JETS VIA THE KINETIC KELVIN-HELMHOLTZ INSTABILITY

Author

Yosuke Mizuno, Martin Pohl, Helene Sol, Bing Zhang, Ioana Duţan, Ken-Ichi Nishikawa, Jacek Niemiec, P. E. Hardee, Dieter H. Hartmann, Mikhail V. Medvedev, A. Meli, National Space Science and Technology Center (NSSTC), NASA Marshall Space Flight Center (MSFC)-University of Alabama in Huntsville (UAH), University of Malta [Malta], Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Matériaux, ingénierie et science [Villeurbanne] (MATEIS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), University of Alabama in Huntsville (UAH)-NASA Marshall Space Flight Center (MSFC), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées de Lyon (INSA Lyon), and Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)

Subjects
PARTICLE-ACCELERATION, MAGNETOHYDRODYNAMIC SIMULATIONS, FOS: Physical sciences, Electron, magnetic fields, 01 natural sciences, Instability, symbols.namesake, Relativistic plasma, Physics::Plasma Physics, 0103 physical sciences, 010306 general physics, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, relativistic processes, acceleration of particles, RAY BURST SOURCES, High Energy Astrophysical Phenomena (astro-ph.HE), [PHYS]Physics [physics], Physics, Debye sheath, Institut für Physik und Astronomie, Astronomy and Astrophysics, Plasma, non-thermal [radiation mechanisms], plasmas, ELECTRON-POSITRON PLASMAS, Physics - Plasma Physics, PROMPT, Magnetic field, Computational physics, Plasma Physics (physics.plasm-ph), Shear (sheet metal), Weibel instability, jets [stars], WEIBEL INSTABILITY, Classical mechanics, Physics and Astronomy, Space and Planetary Science, MECHANICS, Physics::Space Physics, symbols, RADIATION, ddc:520, Astrophysics - High Energy Astrophysical Phenomena, EMISSION, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], RELATIVISTIC COLLISIONLESS SHOCKS
Abstract

We have investigated magnetic field generation in velocity shears via the kinetic Kelvin-Helmholtz instability (kKHI) using a relativistic plasma jet core and stationary plasma sheath. Our three-dimensional particle-in-cell simulations consider plasma jet cores with Lorentz factors of 1.5, 5, and 15 for both electron-proton and electron-positron plasmas. For electron-proton plasmas we find generation of strong large-scale DC currents and magnetic fields which extend over the entire shear-surface and reach thicknesses of a few tens of electron skin depths. For electron-positron plasmas we find generation of alternating currents and magnetic fields. Jet and sheath plasmas are accelerated across the shear surface in the strong magnetic fields generated by the kKHI. The mixing of jet and sheath plasmas generates transverse structure similar to that produced by the Weibel instability., Comment: 28 pages, 12 figures, in press, ApJ, September 10, 2014

Published
2014
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42. Double Slit Experient Still Has Much to Offer (9): ---Continuously Curved Diffraction Patterns of 2D-Cross-Grating Experiments

Author

Peng, Hui and University of Alabama in Huntsville (UAH)

Subjects
[PHYS]Physics [physics], genetic structures, grating experiment, curved diffraction pattern, expanded diffraction pattern, sense organs, cross-grating experiment, eye diseases, diffraction pattern, inclined diffraction pattern
Abstract

Young's double slit experiments represent the mystery of quantum mechanics. To explore the mystery, varieties of the single slit, double slit, cross-double slit and 1D-grating experiments were performed, which show the universal phenomena that the interference/diffraction patterns are curved, expanded and inclined. In this article, we show novel phenomena that the diffraction patterns of the 2D-cross-grating experiments can be curved, expanded and inclined simultaneously and continuously. Those experiments provide comprehensive data for developing/testing a theoretical model.

Published
2021

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