Sample records for central outer tracker

  1. Two-axis tracker for solar panels and the like

    DOEpatents

    Liao, Henry H.

    2013-04-16

    A tracker including an outer post having elongated bore and a lower end mounted on a sub-structure, an inner pole rotatably received in the elongated bore, a lower bearing in the bore adjacent a lower end of the outer post and attached thereto to be constrained from lateral movement and mounted on the sub-structure such that a lower end of the inner pole rests on and is supported by the lower bearing, an upper bearing near an upper end of the outer post, a circumferential drive supported on the outer post for rotating the inner pole relative to the outer post, such that substantially a full weight of a load on the inner pole is directly transmitted to the sub-structure and lateral force and torque leverage are placed on a full length of the outer post by way of the upper and lower bearing.

  2. Macro Pixel ASIC (MPA): the readout ASIC for the pixel-strip (PS) module of the CMS outer tracker at HL-LHC

    NASA Astrophysics Data System (ADS)

    Ceresa, D.; Marchioro, A.; Kloukinas, K.; Kaplon, J.; Bialas, W.; Re, V.; Traversi, G.; Gaioni, L.; Ratti, L.

    2014-11-01

    The CMS tracker at HL-LHC is required to provide prompt information on particles with high transverse momentum to the central Level 1 trigger. For this purpose, the innermost part of the outer tracker is based on a combination of a pixelated sensor with a short strip sensor, the so-called Pixel-Strip module (PS). The readout of these sensors is carried out by distinct ASICs, the Strip Sensor ASIC (SSA), for the strip layer, and the Macro Pixel ASIC (MPA) for the pixel layer. The processing of the data directly on the front-end module represents a design challenge due to the large data volume (30720 pixels and 1920 strips per module) and the limited power budget. This is the reason why several studies have been carried out to find the best compromise between ASICs performance and power consumption. This paper describes the current status of the MPA ASIC development where the logic for generating prompt information on particles with high transverse momentum is implemented. An overview of the readout method is presented with particular attention on the cluster reduction, position encoding and momentum discrimination logic. Concerning the architectural studies, a software test bench capable of reading physics Monte-Carlo generated events has been developed and used to validate the MPA design and to evaluate the MPA performance. The MPA-Light is scheduled to be submitted for fabrication this year and will include the full analog functions and a part of the digital logic of the final version in order to qualify the chosen VLSI technology for the analog front-end, the module assembly and the low voltage digital supply.

  3. Live Imaging of LysoTracker-Labelled Phagolysosomes Tracks Diurnal Phagocytosis of Photoreceptor Outer Segment Fragments in Rat RPE Tissue Ex Vivo.

    PubMed

    Mao, Yingyu; Finnemann, Silvia C

    2016-01-01

    Renewal of rod photoreceptor outer segments in the mammalian eye involves synchronized diurnal shedding after light onset of spent distal outer segment fragments (POS) linked to swift clearance of shed POS from the subretinal space by the adjacent retinal pigment epithelium (RPE). Engulfed POS phagosomes in RPE cells mature to acidified phagolysosomes, which accomplish enzymatic degradation of POS macromolecules. Here, we used an acidophilic fluorophore LysoTracker to label acidic organelles in freshly dissected, live rat RPE tissue flat mounts. We observed that all RPE cells imaged contained numerous acidified POS phagolysosomes whose abundance per cell was dramatically increased 2 h after light onset as compared to either 1 h before or 4 h after light onset. Lack of organelles of similar diameter (of 1-2 μm) in phagocytosis-defective mutant RCS rat RPE confirmed that LysoTracker live imaging detected POS phagolysosomes. Lack of increase in lysosomal membrane protein LAMP-1 in RPE/choroid during the diurnal phagocytic burst suggests that formation of POS phagolysosomes in RPE in situ may not involve extra lysosome membrane biogenesis. Taken together, we report a new imaging approach that directly detects POS phagosome acidification and allows rapid tracking and quantification of POS phagocytosis by live RPE -tissue ex situ.

  4. P-Type Silicon Strip Sensors for the new CMS Tracker at HL-LHC

    NASA Astrophysics Data System (ADS)

    Adam, W.; Bergauer, T.; Brondolin, E.; Dragicevic, M.; Friedl, M.; Frühwirth, R.; Hoch, M.; Hrubec, J.; König, A.; Steininger, H.; Waltenberger, W.; Alderweireldt, S.; Beaumont, W.; Janssen, X.; Lauwers, J.; Van Mechelen, P.; Van Remortel, N.; Van Spilbeeck, A.; Beghin, D.; Brun, H.; Clerbaux, B.; Delannoy, H.; De Lentdecker, G.; Fasanella, G.; Favart, L.; Goldouzian, R.; Grebenyuk, A.; Karapostoli, G.; Lenzi, Th.; Léonard, A.; Luetic, J.; Postiau, N.; Seva, T.; Vanlaer, P.; Vannerom, D.; Wang, Q.; Zhang, F.; Abu Zeid, S.; Blekman, F.; De Bruyn, I.; De Clercq, J.; D'Hondt, J.; Deroover, K.; Lowette, S.; Moortgat, S.; Moreels, L.; Python, Q.; Skovpen, K.; Van Mulders, P.; Van Parijs, I.; Bakhshiansohi, H.; Bondu, O.; Brochet, S.; Bruno, G.; Caudron, A.; Delaere, C.; Delcourt, M.; De Visscher, S.; Francois, B.; Giammanco, A.; Jafari, A.; Komm, M.; Krintiras, G.; Lemaitre, V.; Magitteri, A.; Mertens, A.; Michotte, D.; Musich, M.; Piotrzkowski, K.; Quertenmont, L.; Szilasi, N.; Vidal Marono, M.; Wertz, S.; Beliy, N.; Caebergs, T.; Daubie, E.; Hammad, G. H.; Härkönen, J.; Lampén, T.; Luukka, P.; Peltola, T.; Tuominen, E.; Tuovinen, E.; Eerola, P.; Tuuva, T.; Baulieu, G.; Boudoul, G.; Caponetto, L.; Combaret, C.; Contardo, D.; Dupasquier, T.; Gallbit, G.; Lumb, N.; Mirabito, L.; Perries, S.; Vander Donckt, M.; Viret, S.; Agram, J.-L.; Andrea, J.; Bloch, D.; Bonnin, C.; Brom, J.-M.; Chabert, E.; Chanon, N.; Charles, L.; Conte, E.; Fontaine, J.-Ch.; Gross, L.; Hosselet, J.; Jansova, M.; Tromson, D.; Autermann, C.; Feld, L.; Karpinski, W.; Kiesel, K. M.; Klein, K.; Lipinski, M.; Ostapchuk, A.; Pierschel, G.; Preuten, M.; Rauch, M.; Schael, S.; Schomakers, C.; Schulz, J.; Schwering, G.; Wlochal, M.; Zhukov, V.; Pistone, C.; Fluegge, G.; Kuensken, A.; Pooth, O.; Stahl, A.; Aldaya, M.; Asawatangtrakuldee, C.; Beernaert, K.; Bertsche, D.; Contreras-Campana, C.; Eckerlin, G.; Eckstein, D.; Eichhorn, T.; Gallo, E.; Garay Garcia, J.; Hansen, K.; Haranko, M.; Harb, A.; Hauk, J.; Keaveney, J.; Kalogeropoulos, A.; Kleinwort, C.; Lohmann, W.; Mankel, R.; Maser, H.; Mittag, G.; Muhl, C.; Mussgiller, A.; Pitzl, D.; Reichelt, O.; Savitskyi, M.; Schuetze, P.; Walsh, R.; Zuber, A.; Biskop, H.; Buhmann, P.; Centis-Vignali, M.; Garutti, E.; Haller, J.; Hoffmann, M.; Lapsien, T.; Matysek, M.; Perieanu, A.; Scharf, Ch.; Schleper, P.; Schmidt, A.; Schwandt, J.; Sonneveld, J.; Steinbrück, G.; Vormwald, B.; Wellhausen, J.; Abbas, M.; Amstutz, C.; Barvich, T.; Barth, Ch.; Boegelspacher, F.; De Boer, W.; Butz, E.; Caselle, M.; Colombo, F.; Dierlamm, A.; Freund, B.; Hartmann, F.; Heindl, S.; Husemann, U.; Kornmayer, A.; Kudella, S.; Muller, Th.; Simonis, H. J.; Steck, P.; Weber, M.; Weiler, Th.; Anagnostou, G.; Asenov, P.; Assiouras, P.; Daskalakis, G.; Kyriakis, A.; Loukas, D.; Paspalaki, L.; Siklér, F.; Veszprémi, V.; Bhardwaj, A.; Dalal, R.; Jain, G.; Ranjan, K.; Bakhshiansohl, H.; Behnamian, H.; Khakzad, M.; Naseri, M.; Cariola, P.; Creanza, D.; De Palma, M.; De Robertis, G.; Fiore, L.; Franco, M.; Loddo, F.; Silvestris, L.; Maggi, G.; Martiradonna, S.; My, S.; Selvaggi, G.; Albergo, S.; Cappello, G.; Chiorboli, M.; Costa, S.; Di Mattia, A.; Giordano, F.; Potenza, R.; Saizu, M. A.; Tricomi, A.; Tuve, C.; Barbagli, G.; Brianzi, M.; Ciaranfi, R.; Ciulli, V.; Civinini, C.; D'Alessandro, R.; Focardi, E.; Latino, G.; Lenzi, P.; Meschini, M.; Paoletti, S.; Russo, L.; Scarlini, E.; Sguazzoni, G.; Strom, D.; Viliani, L.; Ferro, F.; Lo Vetere, M.; Robutti, E.; Dinardo, M. E.; Fiorendi, S.; Gennai, S.; Malvezzi, S.; Manzoni, R. A.; Menasce, D.; Moroni, L.; Pedrini, D.; Azzi, P.; Bacchetta, N.; Bisello, D.; Dall'Osso, M.; Pozzobon, N.; Tosi, M.; De Canio, F.; Gaioni, L.; Manghisoni, M.; Nodari, B.; Riceputi, E.; Re, V.; Traversi, G.; Comotti, D.; Ratti, L.; Alunni Solestizi, L.; Biasini, M.; Bilei, G. M.; Cecchi, C.; Checcucci, B.; Ciangottini, D.; Fanò, L.; Gentsos, C.; Ionica, M.; Leonardi, R.; Manoni, E.; Mantovani, G.; Marconi, S.; Mariani, V.; Menichelli, M.; Modak, A.; Morozzi, A.; Moscatelli, F.; Passeri, D.; Placidi, P.; Postolache, V.; Rossi, A.; Saha, A.; Santocchia, A.; Storchi, L.; Spiga, D.; Androsov, K.; Azzurri, P.; Arezzini, S.; Bagliesi, G.; Basti, A.; Boccali, T.; Borrello, L.; Bosi, F.; Castaldi, R.; Ciampa, A.; Ciocci, M. A.; Dell'Orso, R.; Donato, S.; Fedi, G.; Giassi, A.; Grippo, M. T.; Ligabue, F.; Lomtadze, T.; Magazzu, G.; Martini, L.; Mazzoni, E.; Messineo, A.; Moggi, A.; Morsani, F.; Palla, F.; Palmonari, F.; Raffaelli, F.; Rizzi, A.; Savoy-Navarro, A.; Spagnolo, P.; Tenchini, R.; Tonelli, G.; Venturi, A.; Verdini, P. G.; Bellan, R.; Costa, M.; Covarelli, R.; Da Rocha Rolo, M.; Demaria, N.; Rivetti, A.; Dellacasa, G.; Mazza, G.; Migliore, E.; Monteil, E.; Pacher, L.; Ravera, F.; Solano, A.; Fernandez, M.; Gomez, G.; Jaramillo Echeverria, R.; Moya, D.; Gonzalez Sanchez, F. J.; Vila, I.; Virto, A. L.; Abbaneo, D.; Ahmed, I.; Albert, E.; Auzinger, G.; Berruti, G.; Bianchi, G.; Blanchot, G.; Bonnaud, J.; Caratelli, A.; Ceresa, D.; Christiansen, J.; Cichy, K.; Daguin, J.; D'Auria, A.; Detraz, S.; Deyrail, D.; Dondelewski, O.; Faccio, F.; Frank, N.; Gadek, T.; Gill, K.; Honma, A.; Hugo, G.; Jara Casas, L. M.; Kaplon, J.; Kornmayer, A.; Kottelat, L.; Kovacs, M.; Krammer, M.; Lenoir, P.; Mannelli, M.; Marchioro, A.; Marconi, S.; Mersi, S.; Martina, S.; Michelis, S.; Moll, M.; Onnela, A.; Orfanelli, S.; Pavis, S.; Peisert, A.; Pernot, J.-F.; Petagna, P.; Petrucciani, G.; Postema, H.; Rose, P.; Tropea, P.; Troska, J.; Tsirou, A.; Vasey, F.; Vichoudis, P.; Verlaat, B.; Zwalinski, L.; Bachmair, F.; Becker, R.; di Calafiori, D.; Casal, B.; Berger, P.; Djambazov, L.; Donega, M.; Grab, C.; Hits, D.; Hoss, J.; Kasieczka, G.; Lustermann, W.; Mangano, B.; Marionneau, M.; Martinez Ruiz del Arbol, P.; Masciovecchio, M.; Meinhard, M.; Perozzi, L.; Roeser, U.; Starodumov, A.; Tavolaro, V.; Wallny, R.; Zhu, D.; Amsler, C.; Bösiger, K.; Caminada, L.; Canelli, F.; Chiochia, V.; de Cosa, A.; Galloni, C.; Hreus, T.; Kilminster, B.; Lange, C.; Maier, R.; Ngadiuba, J.; Pinna, D.; Robmann, P.; Taroni, S.; Yang, Y.; Bertl, W.; Deiters, K.; Erdmann, W.; Horisberger, R.; Kaestli, H.-C.; Kotlinski, D.; Langenegger, U.; Meier, B.; Rohe, T.; Streuli, S.; Cussans, D.; Flacher, H.; Goldstein, J.; Grimes, M.; Jacob, J.; Seif El Nasr-Storey, S.; Cole, J.; Hoad, C.; Hobson, P.; Morton, A.; Reid, I. D.; Auzinger, G.; Bainbridge, R.; Dauncey, P.; Hall, G.; James, T.; Magnan, A.-M.; Pesaresi, M.; Raymond, D. M.; Uchida, K.; Garabedian, A.; Heintz, U.; Narain, M.; Nelson, J.; Sagir, S.; Speer, T.; Swanson, J.; Tersegno, D.; Watson-Daniels, J.; Chertok, M.; Conway, J.; Conway, R.; Flores, C.; Lander, R.; Pellett, D.; Ricci-Tam, F.; Squires, M.; Thomson, J.; Yohay, R.; Burt, K.; Ellison, J.; Hanson, G.; Olmedo, M.; Si, W.; Yates, B. R.; Gerosa, R.; Sharma, V.; Vartak, A.; Yagil, A.; Zevi Della Porta, G.; Dutta, V.; Gouskos, L.; Incandela, J.; Kyre, S.; Mullin, S.; Patterson, A.; Qu, H.; White, D.; Dominguez, A.; Bartek, R.; Cumalat, J. P.; Ford, W. T.; Jensen, F.; Johnson, A.; Krohn, M.; Leontsinis, S.; Mulholland, T.; Stenson, K.; Wagner, S. R.; Apresyan, A.; Bolla, G.; Burkett, K.; Butler, J. N.; Canepa, A.; Cheung, H. W. K.; Chramowicz, J.; Christian, D.; Cooper, W. E.; Deptuch, G.; Derylo, G.; Gingu, C.; Grünendahl, S.; Hasegawa, S.; Hoff, J.; Howell, J.; Hrycyk, M.; Jindariani, S.; Johnson, M.; Kahlid, F.; Lei, C. M.; Lipton, R.; Lopes De Sá, R.; Liu, T.; Los, S.; Matulik, M.; Merkel, P.; Nahn, S.; Prosser, A.; Rivera, R.; Schneider, B.; Sellberg, G.; Shenai, A.; Spiegel, L.; Tran, N.; Uplegger, L.; Voirin, E.; Berry, D. R.; Chen, X.; Ennesser, L.; Evdokimov, A.; Evdokimov, O.; Gerber, C. E.; Hofman, D. J.; Makauda, S.; Mills, C.; Sandoval Gonzalez, I. D.; Alimena, J.; Antonelli, L. J.; Francis, B.; Hart, A.; Hill, C. S.; Parashar, N.; Stupak, J.; Bortoletto, D.; Bubna, M.; Hinton, N.; Jones, M.; Miller, D. H.; Shi, X.; Tan, P.; Baringer, P.; Bean, A.; Khalil, S.; Kropivnitskaya, A.; Majumder, D.; Wilson, G.; Ivanov, A.; Mendis, R.; Mitchell, T.; Skhirtladze, N.; Taylor, R.; Anderson, I.; Fehling, D.; Gritsan, A.; Maksimovic, P.; Martin, C.; Nash, K.; Osherson, M.; Swartz, M.; Xiao, M.; Bloom, K.; Claes, D. R.; Fangmeier, C.; Gonzalez Suarez, R.; Monroy, J.; Siado, J.; Hahn, K.; Sevova, S.; Sung, K.; Trovato, M.; Bartz, E.; Gershtein, Y.; Halkiadakis, E.; Kyriacou, S.; Lath, A.; Nash, K.; Osherson, M.; Schnetzer, S.; Stone, R.; Walker, M.; Malik, S.; Norberg, S.; Ramirez Vargas, J. E.; Alyari, M.; Dolen, J.; Godshalk, A.; Harrington, C.; Iashvili, I.; Kharchilava, A.; Nguyen, D.; Parker, A.; Rappoccio, S.; Roozbahani, B.; Alexander, J.; Chaves, J.; Chu, J.; Dittmer, S.; McDermott, K.; Mirman, N.; Rinkevicius, A.; Ryd, A.; Salvati, E.; Skinnari, L.; Soffi, L.; Tao, Z.; Thom, J.; Tucker, J.; Zientek, M.; Akgün, B.; Ecklund, K. M.; Kilpatrick, M.; Nussbaum, T.; Zabel, J.; Betchart, B.; Covarelli, R.; Demina, R.; Hindrichs, O.; Petrillo, G.; Eusebi, R.; Osipenkov, I.; Perloff, A.; Ulmer, K. A.

    2017-06-01

    The upgrade of the LHC to the High-Luminosity LHC (HL-LHC) is expected to increase the LHC design luminosity by an order of magnitude. This will require silicon tracking detectors with a significantly higher radiation hardness. The CMS Tracker Collaboration has conducted an irradiation and measurement campaign to identify suitable silicon sensor materials and strip designs for the future outer tracker at the CMS experiment. Based on these results, the collaboration has chosen to use n-in-p type silicon sensors and focus further investigations on the optimization of that sensor type. This paper describes the main measurement results and conclusions that motivated this decision.

  5. Which cue to ‘want’? Opioid stimulation of central amygdala makes goal-trackers show stronger goal-tracking, just as sign-trackers show stronger sign-tracking

    PubMed Central

    DiFeliceantonio, Alexandra G.; Berridge, Kent C.

    2012-01-01

    Pavlovian cues that have been paired with reward can gain incentive salience. Drug addicts find drug cues motivationally attractive and binge eaters are attracted by food cues. But the level of incentive salience elicited by a cue re-encounter still varies across time and brain states. In an animal model, cues become attractive and ‘wanted’ in an ‘autoshaping’ paradigm, where different targets of incentive salience emerge for different individuals. Some individuals (sign-trackers) find a predictive discrete cue attractive while others find a reward contiguous and goal cue more attractive (location where reward arrives: goal-trackers). Here we assessed whether central amygdala mu opioid receptor stimulation enhances the phasic incentive salience of the goal-cue for goal-trackers during moments of predictive cue presence (expressed in both approach and consummatory behaviors to goal cue), just as it enhances the attractiveness of the predictive cue target for sign-trackers. Using detailed video analysis we measured the approaches, nibbles, sniffs, and bites directed at their preferred target for both sign-trackers and goal-trackers. We report that DAMGO microinjections in central amygdala made goal-trackers, like sign-trackers, show phasic increases in appetitive nibbles and sniffs directed at the goal-cue expressed selectively whenever the predictive cue was present. This indicates enhancement of incentive salience attributed by both goal trackers and sign-trackers, but attributed in different directions: each to their own target cue. For both phenotypes, amygdala opioid stimulation makes the individual’s prepotent cue into a stronger motivational magnet at phasic moments triggered by a CS that predicts the reward UCS. PMID:22391118

  6. Outer Continental Shelf Reform Act of 2010

    THOMAS, 111th Congress

    Sen. Bingaman, Jeff [D-NM

    2010-06-21

    Senate - 07/28/2010 Placed on Senate Legislative Calendar under General Orders. Calendar No. 492. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  7. Outer Continental Shelf Permit Processing Coordination Act

    THOMAS, 112th Congress

    Sen. Begich, Mark [D-AK

    2011-04-14

    Senate - 05/17/2011 Committee on Energy and Natural Resources. Hearings held. Hearings printed: S.Hrg. 112-51. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  8. Outer Continental Shelf Reform Act of 2011

    THOMAS, 112th Congress

    Sen. Bingaman, Jeff [D-NM

    2011-05-09

    Senate - 05/17/2011 Committee on Energy and Natural Resources. Hearings held. Hearings printed: S.Hrg. 112-51. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  9. P-Type Silicon Strip Sensors for the new CMS Tracker at HL-LHC

    DOE PAGES

    Adam, W.; Bergauer, T.; Brondolin, E.; ...

    2017-06-27

    The upgrade of the LHC to the High-Luminosity LHC (HL-LHC) is expected to increase the LHC design luminosity by an order of magnitude. This will require silicon tracking detectors with a significantly higher radiation hardness. The CMS Tracker Collaboration has conducted an irradiation and measurement campaign to identify suitable silicon sensor materials and strip designs for the future outer tracker at the CMS experiment. Based on these results, the collaboration has chosen to use n-in-p type silicon sensors and focus further investigations on the optimization of that sensor type. Furthermore, this paper describes the main measurement results and conclusions thatmore » motivated this decision.« less

  10. P-Type Silicon Strip Sensors for the new CMS Tracker at HL-LHC

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

    Adam, W.; Bergauer, T.; Brondolin, E.

    The upgrade of the LHC to the High-Luminosity LHC (HL-LHC) is expected to increase the LHC design luminosity by an order of magnitude. This will require silicon tracking detectors with a significantly higher radiation hardness. The CMS Tracker Collaboration has conducted an irradiation and measurement campaign to identify suitable silicon sensor materials and strip designs for the future outer tracker at the CMS experiment. Based on these results, the collaboration has chosen to use n-in-p type silicon sensors and focus further investigations on the optimization of that sensor type. Furthermore, this paper describes the main measurement results and conclusions thatmore » motivated this decision.« less

  11. Outer Continental Shelf Transboundary Hydrocarbon Agreements Authorization Act

    THOMAS, 113th Congress

    Rep. Duncan, Jeff [R-SC-3

    2013-04-18

    Senate - 10/01/2013 Committee on Energy and Natural Resources. Hearings held. Hearings printed: S.Hrg. 113-104. (All Actions) Tracker: This bill has the status Passed HouseHere are the steps for Status of Legislation:

  12. Outer Continental Shelf Lands Act Amendments Act of 2010

    THOMAS, 111th Congress

    Sen. Whitehouse, Sheldon [D-RI

    2010-05-11

    Senate - 05/25/2010 Committee on Energy and Natural Resources. Hearings held. Hearings printed: S.Hrg. 111-679, pt. 3. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  13. Bidirectional chaos communication between two outer semiconductor lasers coupled mutually with a central semiconductor laser.

    PubMed

    Li, Ping; Wu, Jia-Gui; Wu, Zheng-Mao; Lin, Xiao-Dong; Deng, Dao; Liu, Yu-Ran; Xia, Guang-Qiong

    2011-11-21

    Based on a linear chain composed of a central semiconductor laser and two outer semiconductor lasers, chaos synchronization and bidirectional communication between two outer lasers have been investigated under the case that the central laser and the two outer lasers are coupled mutually, whereas there exists no coupling between the two outer lasers. The simulation results show that high-quality and stable isochronal synchronization between the two outer lasers can be achieved, while the cross-correlation coefficients between the two outer lasers and the central laser are very low under proper operation condition. Based on the high performance chaos synchronization between the two outer lasers, message bidirectional transmissions of bit rates up to 20 Gbit/s can be realized through adopting a novel decoding scheme which is different from that based on chaos pass filtering effect. Furthermore, the security of bidirectional communication is also analyzed. © 2011 Optical Society of America

  14. Improved performance of the LHCb Outer Tracker in LHC Run 2

    NASA Astrophysics Data System (ADS)

    d'Argent, P.; Dufour, L.; Grillo, L.; de Vries, J. A.; Ukleja, A.; Aaij, R.; Archilli, F.; Bachmann, S.; Berninghoff, D.; Birnkraut, A.; Blouw, J.; De Cian, M.; Ciezarek, G.; Färber, C.; Demmer, M.; Dettori, F.; Gersabeck, E.; Grabowski, J.; Hulsbergen, W. D.; Khanji, B.; Kolpin, M.; Kucharczyk, M.; Malecki, B. P.; Merk, M.; Mulder, M.; Müller, J.; Mueller, V.; Pellegrino, A.; Pikies, M.; Rachwal, B.; Schmelzer, T.; Spaan, B.; Szczekowski, M.; van Tilburg, J.; Tolk, S.; Tuning, N.; Uwer, U.; Wishahi, J.; Witek, M.

    2017-11-01

    The LHCb Outer Tracker is a gaseous detector covering an area of 5 × 6 m2 with 12 double layers of straw tubes. The performance of the detector is presented based on data of the LHC Run 2 running period from 2015 and 2016. Occupancies and operational experience for data collected in pp, pPb and PbPb collisions are described. An updated study of the ageing effects is presented showing no signs of gain deterioration or other radiation damage effects. In addition several improvements with respect to LHC Run 1 data taking are introduced. A novel real-time calibration of the time-alignment of the detector and the alignment of the single monolayers composing detector modules are presented, improving the drift-time and position resolution of the detector by 20%. Finally, a potential use of the improved resolution for the timing of charged tracks is described, showing the possibility to identify low-momentum hadrons with their time-of-flight.

  15. Photovoltaic module mounting clip with integral grounding

    DOEpatents

    Lenox, Carl J.

    2008-10-14

    An electrically conductive mounting/grounding clip, for use with a photovoltaic assembly of the type having an electrically conductive frame, comprises an electrically conductive body. The body has a central portion and first and second spaced-apart arms extending generally perpendicular to the central portion. Each arm has an outer portion with each outer portion having an outer end. At least one frame surface-disrupting element is at each outer end. The central portion defines a plane with the frame surface-disrupting elements pointing towards the plane. In some examples each arm extends from the central portion at an acute angle to the plane.

  16. A large ultra-clean gas system with closed loop for the high-rate Outer Tracker at HERA-B

    NASA Astrophysics Data System (ADS)

    Hohlmann, Marcus

    2003-12-01

    The gas system for the Outer Tracker of the HERA-B experiment at DESY produces the desired counting gas mixture Ar/CF 4/CO 2 65:30:5 and circulates it through the detector at a flow rate of 20 m3/ h, i.e. ˜1 vol/ h. It controls flows and regulates pressures in all 26 OTR half-superlayers, purifies the gas upon return from the detector, and automatically performs a quantitative analysis of main and trace (O 2, N 2, H 2O) gas components for the common input and the outputs of all half-superlayers. The first running experience and the strategies employed during system construction to avoid any detector aging possibly induced by the gas system are discussed. The large system with major gas purification stations was constructed using only non-outgassing, "clean" materials and devices, such as stainless steel, PEEK, baked Viton, and metal bellows pumps. An epoxy glue was used extensively as a non-outgassing sealing material in applications with up to 100 bar pressure.

  17. Radiation hardness and timing studies of a monolithic TowerJazz pixel design for the new ATLAS Inner Tracker

    NASA Astrophysics Data System (ADS)

    Riegel, C.; Backhaus, M.; Van Hoorne, J. W.; Kugathasan, T.; Musa, L.; Pernegger, H.; Riedler, P.; Schaefer, D.; Snoeys, W.; Wagner, W.

    2017-01-01

    A part of the upcoming HL-LHC upgrade of the ATLAS Detector is the construction of a new Inner Tracker. This upgrade opens new possibilities, but also presents challenges in terms of occupancy and radiation tolerance. For the pixel detector inside the inner tracker, hybrid modules containing passive silicon sensors and connected readout chips are presently used, but require expensive assembly techniques like fine-pitch bump bonding. Silicon devices fabricated in standard commercial CMOS technologies, which include part or all of the readout chain, are also investigated offering a reduced cost as they are cheaper per unit area than traditional silicon detectors. If they contain the full readout chain, as for a fully monolithic approach, there is no need for the expensive flip-chip assembly, resulting in a further cost reduction and material savings. In the outer pixel layers of the ATLAS Inner Tracker, the pixel sensors must withstand non-ionising energy losses of up to 1015 n/cm2 and offer a timing resolution of 25 ns or less. This paper presents test results obtained on a monolithic test chip, the TowerJazz 180nm Investigator, towards these specifications. The presented program of radiation hardness and timing studies has been launched to investigate this technology's potential for the new ATLAS Inner Tracker.

  18. Photoconductive switch package

    DOEpatents

    Ca[rasp, George J

    2013-10-22

    A photoconductive switch is formed of a substrate that has a central portion of SiC or other photoconductive material and an outer portion of cvd-diamond or other suitable material surrounding the central portion. Conducting electrodes are formed on opposed sides of the substrate, with the electrodes extending beyond the central portion and the edges of the electrodes lying over the outer portion. Thus any high electric fields produced at the edges of the electrodes lie outside of and do not affect the central portion, which is the active switching element. Light is transmitted through the outer portion to the central portion to actuate the switch.

  19. Concentric Coplanar Capacitive Sensor System with Quantitative Model

    NASA Technical Reports Server (NTRS)

    Chen, Tianming (Inventor); Bowler, Nicola (Inventor)

    2014-01-01

    A concentric coplanar capacitive sensor includes a charged central disc forming a first electrode, an outer annular ring coplanar with and outer to the charged central disc, the outer annular ring forming a second electrode, and a gap between the charged central disc and the outer annular ring. The first electrode and the second electrode may be attached to an insulative film. A method provides for determining transcapacitance between the first electrode and the second electrode and using the transcapacitance in a model that accounts for a dielectric test piece to determine inversely the properties of the dielectric test piece.

  20. Electrochemical cell design

    DOEpatents

    Arntzen, John D.

    1978-01-01

    An electrochemical cell includes two outer electrodes and a central electrode of opposite polarity, all nested within a housing having two symmetrical halves which together form an offset configuration. The outer electrodes are nested within raised portions within the side walls of each housing half while the central electrode sealingly engages the perimetric margins of the side-wall internal surfaces. Suitable interelectrode separators and electrical insulating material electrically isolate the central electrode from the housing and the outer electrodes. The outer electrodes are electrically connected to the internal surfaces of the cell housing to provide current collection. The nested structure minimizes void volume that would otherwise be filled with gas or heavy electrolyte and also provides perimetric edge surfaces for sealing and supporting at the outer margins of frangible interelectrode separator layers.

  1. Induced radioactivity in the forward shielding and semiconductor tracker of the ATLAS detector.

    PubMed

    Bĕdajánek, I; Linhart, V; Stekl, I; Pospísil, S; Kolros, A; Kovalenko, V

    2005-01-01

    The radioactivity induced in the forward shielding, copper collimator and semiconductor tracker modules of the ATLAS detector has been studied. The ATLAS detector is a long-term experiment which, during operation, will require to have service and access to all of its parts and components. The radioactivity induced in the forward shielding was calculated by Monte Carlo methods based on GEANT3 software tool. The results show that the equivalent dose rates on the outer surface of the forward shielding are very low (at most 0.038 microSv h(-1)). On the other hand, the equivalent dose rates are significantly higher on the inner surface of the forward shielding (up to 661 microSv h(-1)) and, especially, at the copper collimator close to the beampipe (up to 60 mSv h(-1)). The radioactivity induced in the semiconductor tracker modules was studied experimentally. The module was activated by neutrons in a training nuclear reactor and the delayed gamma ray spectra were measured. From these measurements, the equivalent dose rate on the surface of the semiconductor tracker module was estimated to be < 100 microSv h(-1) after 100 d of Large Hadron Collider (LHC) operation and 10 d of cooling.

  2. 76 FR 70748 - Outer Continental Shelf (OCS), Central and Western Gulf of Mexico, Oil and Gas Lease Sales for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-15

    ... DEPARTMENT OF THE INTERIOR Bureau of Ocean Energy Management Outer Continental Shelf (OCS), Central and Western Gulf of Mexico, Oil and Gas Lease Sales for Years 2012-2017 AGENCY: Bureau of Ocean... 229, Western GOM 2012 Sale 227, Central GOM 2013 Sale 233, Western GOM 2013 Sale 231, Central GOM 2014...

  3. High voltage feedthrough bushing

    DOEpatents

    Brucker, John P.

    1993-01-01

    A feedthrough bushing for a high voltage diode provides for using compression sealing for all sealing surfaces. A diode assembly includes a central conductor extending through the bushing and a grading ring assembly circumferentially surrounding and coaxial with the central conductor. A flexible conductive plate extends between and compressively seals against the central conductor and the grading ring assembly, wherein the flexibility of the plate allows inner and outer portions of the plate to axially translate for compression sealing against the central conductor and the grading ring assembly, respectively. The inner portion of the plate is bolted to the central conductor for affecting sealing. A compression beam is also bolted to the central conductor and engages the outer portion of the plate to urge the outer portion toward the grading ring assembly to obtain compression sealing therebetween.

  4. Photoconductive switch package

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

    Caporaso, George J.

    2015-10-27

    A photoconductive switch is formed of a substrate that has a central portion of SiC or other photoconductive material and an outer portion of cvd-diamond or other suitable material surrounding the central portion. Conducting electrodes are formed on opposed sides of the substrate, with the electrodes extending beyond the central portion and the edges of the electrodes lying over the outer portion. Thus any high electric fields produced at the edges of the electrodes lie outside of and do not affect the central portion, which is the active switching element. Light is transmitted through the outer portion to the centralmore » portion to actuate the switch.« less

  5. Eddy Current Minimizing Flow Plug for Use in Flow Conditioning and Flow Metering

    NASA Technical Reports Server (NTRS)

    England, John Dwight (Inventor); Kelley, Anthony R. (Inventor)

    2015-01-01

    An eddy-current-minimizing flow plug has an outer radial wall with open flow channels formed between the plug's inlet and outlet. The plug has a central region coupled to the inner surface of the outer radial wall. Each open flow channel includes (i) a first portion originating at the inlet and converging to a location in the plug where convergence is contributed to by changes in thickness of the outer radial wall and divergence of the central region, and (ii) a second portion originating in the plug and diverging to the outlet where divergence is contributed to by changes in thickness of the outer radial wall and convergence of the central region. For at least a portion of the open flow channels, a central axis passing through the first and second portions is non-parallel with respect to the given direction of the flow.

  6. Formation of star tracking reticles

    NASA Technical Reports Server (NTRS)

    Smith, W. O.; Toft, A. R. (Inventor)

    1974-01-01

    The present application is directed towards a process for producing high resolution, substantially non-reflective reticles or choppers suitable for use for transmitting in both the visible and near ultra-violet regions, able to withstand reasonable handling and extreme environmental conditions, and capable of operating at speeds of from 2800 to about 9000 revolutions per minute without distortion. In particular, the present invention is directed towards the production or reticles having a quartz base vacuum coated with chromium, chromium-silver alloy, and silver with electrodeposited copper and black chromium thereon, respectively, in the form of a reticle pattern. The quartz permits the transmission of light while the pattern is opaque to light. The reticles of the present invention are intended for use in optical trackers, such as star trackers used in outer space.

  7. Microenvironment Tracker (MicroTrac)

    EPA Science Inventory

    Epidemiologic studies have shown associations between air pollution concentrations measured at central-site ambient monitors and adverse health outcomes. Using central-site concentrations as exposure surrogates, however, can lead to exposure errors due to time spent in various in...

  8. Identification of a cell epitope that is globally conserved among outer membrane proteins (OMPs) OMP7, OMP8, and OMP9 of anaplasma marginale strains and with OMP7 from the A. marginale subsp. centrale vaccine strain

    USDA-ARS?s Scientific Manuscript database

    Within the protective outer membrane fraction of Anaplasma marginale, several vaccine candidates have emerged, including a family of outer membrane proteins (OMPs) 7-9, which share sequence identity with each other and with the single protein OMP7 in the vaccine strain A. marginale subsp. centrale. ...

  9. Central tracker for BM@N experiment based on double side Si-microstrip detectors

    NASA Astrophysics Data System (ADS)

    Kovalev, Yu.; Kapishin, M.; Khabarov, S.; Shafronovskaia, A.; Tarasov, O.; Makankin, A.; Zamiatin, N.; Zubarev, E.

    2017-07-01

    Design of central tracker system based on Double-Sided Silicon Detectors (DSSD) for BM@N experiment is described. A coordinate plane with 10240 measuring channels, pitch adapter, reading electronics was developed. Each element was tested and assembled into a coordinate plane. The first tests of the plane with 106Ru source were carried out before installation for the BM@N experiment. The results of the study indicate that noisy channels and inefficient channels are less than 3%. In general, single clusters 87% (one group per module of consecutive strips) and 75% of clusters with a width equal to one strip.

  10. Multimode optical fiber

    DOEpatents

    Bigot-Astruc, Marianne; Molin, Denis; Sillard, Pierre

    2014-11-04

    A depressed graded-index multimode optical fiber includes a central core, an inner depressed cladding, a depressed trench, an outer depressed cladding, and an outer cladding. The central core has an alpha-index profile. The depressed claddings limit the impact of leaky modes on optical-fiber performance characteristics (e.g., bandwidth, core size, and/or numerical aperture).

  11. High Energy Physics Research with the CMS Experiment at CERN

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

    Hanson, Gail G.

    2013-05-31

    The highlight of our last budget period, June 1, 2010, to May 31, 2013, was the discovery of the Higgs boson by the ATLAS and CMS experiments at the CERN Large Hadron Collider (LHC), announced on July 4, 2012, and for which François Englert and Peter Higgs were awarded the 2013 Nobel Prize in Physics on October 8, 2013. The Higgs boson was postulated in 1964 to explain how elementary particles obtain mass and was the missing piece of the Standard Model. However, the Standard Model does not describe everything that we know. There are many unanswered questions, such asmore » how can the Higgs boson have the mass that we have observed, are there more Higgs bosons, why is there more matter than antimatter, and what is the invisible dark matter, which constitutes about 85% of the matter in the universe. Our group played a significant role in the discovery of the Higgs boson and in subsequent analyses. We also carried out searches for new physics, in ways that could help elucidate some of the remaining questions. Our role in the CMS detector focused on the Tracker, a silicon strip outer tracker and pixel inner tracker.« less

  12. Searches for long-lived charged particles in pp collisions at $$ \\sqrt{s} $$ =7 and 8 TeV

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

    Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.

    2013-07-01

    Results of searches for heavy stable charged particles produced in pp collisions at = 7 and 8 TeV are presented corresponding to an integrated luminosity of 5.0 fb(-1) and 18.8 fb(-1), respectively. Data collected with the CMS detector are used to study the momentum, energy deposition, and time-of-flight of signal candidates. Leptons with an electric charge between e/3 and 8e, as well as bound states that can undergo charge exchange with the detector material, are studied. Analysis results are presented for various combinations of signatures in the inner tracker only, inner tracker and muon detector, and muon detector only. Detectormore » signatures utilized are long time-of-flight to the outer muon system and anomalously high (or low) energy deposition in the inner tracker. The data are consistent with the expected background, and upper limits are set on the production cross section of long-lived gluinos, scalar top quarks, and scalar τ leptons, as well as pair produced long-lived leptons. Corresponding lower mass limits, ranging up to 1322 GeV/c (2) for gluinos, are the most stringent to date.« less

  13. Searches for long-lived charged particles in pp collisions at $$\\sqrt{s}$$ = 7 and 8 TeV

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

    Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.

    2013-07-19

    Results of searches for heavy stable charged particles produced in pp collisions atmore » $$\\sqrt{s}$$ =7 and 8 TeV are presented corresponding to an integrated luminosity of 5.0 fb -1 and 18.8 fb -1, respectively. Data collected with the CMS detector are used to study the momentum, energy deposition, and time-of-flight of signal candidates. Leptons with an electric charge between e/3 and 8e, as well as bound states that can undergo charge exchange with the detector material, are studied. Analysis results are presented for various combinations of signatures in the inner tracker only, inner tracker and muon detector, and muon detector only. Detector signatures utilized are long time-of-flight to the outer muon system and anomalously high (or low) energy deposition in the inner tracker. The data are consistent with the expected background, and upper limits are set on the production cross section of long-lived gluinos, scalar top quarks, and scalar τ leptons, as well as pair produced long-lived leptons. Corresponding lower mass limits, ranging up to 1322 GeV/c (2) for gluinos, are the most stringent to date.« less

  14. Parametric design analysis of a hybrid composite flywheel using a laminated central disc and a filament wound outer ring

    NASA Astrophysics Data System (ADS)

    Nimmer, R. P.

    1980-09-01

    A hybrid flywheel design concept based on the use of a laminated central disk with a filament-wound outer ring is analyzed for several different combinations of composite materials. Some of the results of this study are: (1) an optimized E-glass disk with Kevlar-49 outer ring offers the prospect of 30% additional energy density over a laminated disk without a ring; (2) a laminated S2-glass disk is capable of storing more energy per unit mass than an E-glass disk because of its higher tensile strength; and (3) the use of wound graphite outer rings with S2-glass disks leads to substantial reductions in the size of the interference fit while offering still higher energy densities than for a Kevlar-49 outer ring.

  15. Photovoltaic module mounting clip with integral grounding

    DOEpatents

    Lenox, Carl J.

    2010-08-24

    An electrically conductive mounting/grounding clip, usable with a photovoltaic (PV) assembly of the type having an electrically conductive frame, comprises an electrically conductive body. The body has a central portion and first and second spaced-apart arms extending from the central portion. Each arm has first and second outer portions with frame surface-disrupting element at the outer portions.

  16. Ultra high performance connectors for power transmission applications

    DOEpatents

    Wang, Jy-An; Ren, Fei; Lee, Dominic F; Jiang, Hao

    2014-03-04

    Disclosed are several examples of an apparatus for connecting the free ends of two electrical power transmission lines having conductor strands disposed around a central, reinforcing core. The examples include an inner sleeve having a body defining an inner bore passing through an axially-extending, central axis, an outer rim surface disposed radially outward from the central bore, and one or more axially-extending grooves penetrating the body at the outer rim surface. Also included is an outer splice having a tubular shaped body with a bore passing coaxially through the central axis, the bore defining an inner rim surface for accepting the inner sleeve. The inner bore of the inner sleeve accepts the reinforcement cores of the two conductors, and the grooves accept the conductor strands in an overlapping configuration so that a majority of the electrical current flows between the overlapped conductor strands when the conductors are transmitting electrical current.

  17. Novel Micromegas trackers

    NASA Astrophysics Data System (ADS)

    Sabatie, Franck

    2017-09-01

    The latest development in Micromegas trackers includes the Micromegas Vertex Tracker (MVT) soon to be installed in Jefferson Lab Hall B, in the CLAS12 central tracking system. The MVT is composed of 6 cylindrical layers and 6 flat disks of resistive bulk Micromegas detectors. They have been designed to withstand the high particle flux environment and the high magnetic field using a low material budget of less than 0.5% of a radiation length per detector. The MVT is read out using front-end electronics based on the ``Dream'' Asic developed at CEA Saclay/Irfu. The low material budget requirements and very stringent space restrictions of the central tracking system surrounded by a 5T solenoid prevent the use of on-detector frontend electronics. The ability of the Dream chip to work with high-capacitance detectors allows deploying the electronics some 2 m away using flat micro-coaxial cables. After a short introduction to Micromegas detectors and the state-of-the-art achievements in this technology, I will focus on the CLAS12 MVT detector system, from the fabrication techniques to the readout electronics. Possible future developments will briefly be presented as well.

  18. Tracking instrument and control for solar concentrators. Final technical report, October 1979-January 1981

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

    Gray, J; Kuhlman, J

    1981-01-31

    The tracker uses a single photo sensor, and a rotating aperature to obtain tracking accuracies better than 1.5 mrads (0.1 degs). Peak signal detection is used to eliminate tracking of false sources, i.e., clouds, etc. A prism is employed to obtain an extended field of view (150 degs axially - 360 degs radially). The tracker digitally measures the Suns displacement angle relative to the concentrator axis, and repositions it incrementally. This arrangement permits the use of low cost non-servo motors. The local controller contains microprocessor based electronics, incorporating digital signal processing. A single controller may be time shared by amore » maximum of sixteen trackers, providing a high performance, cost effective solar tracking system, suitable for both line and point focus concentrators. An installation may have the local controller programmed as a standalone unit or slaved to a central controller. When used with a central controller, dynamic data monitoring and logging is available, together with the ability to change system modes and parameters, as desired.« less

  19. The Nonbarred Double-Ringed Galaxy, PGC 1000714

    NASA Astrophysics Data System (ADS)

    Seigar, Marc; Mutlu Pakdil, Burcin; Mangedarage, Mithila; Treuthardt, Patrick M.

    2017-01-01

    Hoag-type galaxies are rare peculiar systems which bear strong resemblance to Hoag's Object with an elliptical-like core, a detached outer ring, and no signs of a bar or stellar disk. They represent extreme cases and help us understand the formation of galaxies in general by providing clues on formation mechanisms. The nature of outer rings in Hoag-type galaxies is still debated and may be related either to slow secular evolution, such as dissolution of a barlike structure or to environmental processes, such as galaxy-galaxy interactions or gas infall. Due to a fairly superficial resemblance to Hoag's Object, PGC 1000714 is a good target for detailed study of the peculiar structure of this type. We present the first photometric study of PGC 1000714 that has not yet been described in the literature. Our aim is to evaluate its structure and properties as well as understand the origin of outer rings in such galaxies. Surface photometry of the central body is performed using near-UV, BVRI and JHK images. Based on the photometric data, the nearly round central body follows a de Vaucouleurs profile almost all the way to the center. The detailed photometry reveals a reddish inner ring-shaped structure that shares the same center as the central body. However, no sign of a bar or stellar disk is detected. The outer ring appears as a bump in the surface brightness profile with a peak brightness of 25.8 mag/arcsec^{2} in the B-band and shows no sharp outer boundary. By reconstructing the observed SED for the central body and the rings, we recover the stellar population properties of the galaxy components. Our work suggests different formation histories for the inner and outer rings. We rule out the secular evolution model as being a formation mechanism for the outer ring. The colors of the outer ring are consistent with a feature that may have experienced a burst of star formation due to a possible recent accretion event. In addition, our work supports that the central body may be formed by a relatively dry major merger or in a single, short and highly effective star formation burst, and the inner ring may be formed as a result of intergalactic medium accretion or secular evolution of a possible gaseous disk

  20. Permanent-magnet switched-flux machine

    DOEpatents

    Trzynadlowski, Andrzej M.; Qin, Ling

    2010-01-12

    A permanent-magnet switched-flux (PMSF) device has a ferromagnetic outer stator mounted to a shaft about a central axis extending axially through the PMSF device. Pluralities of top and bottom stator poles are respectively mounted in first and second circles, radially outwardly in first and second transverse planes extending from first and second sections of the central axis adjacent to an inner surface of the ferromagnetic outer stator. A ferromagnetic inner rotor is coupled to the shaft and has i) a rotor core having a core axis co-axial with the central axis; and ii) first and second discs having respective outer edges with first and second pluralities of permanent magnets (PMs) mounted in first and second circles, radially outwardly from the rotor core axis in the first and second transverse planes. The first and second pluralities of PMs each include PMs of alternating polarity.

  1. Active balance system and vibration balanced machine

    NASA Technical Reports Server (NTRS)

    White, Maurice A. (Inventor); Qiu, Songgang (Inventor); Augenblick, John E. (Inventor); Peterson, Allen A. (Inventor)

    2005-01-01

    An active balance system is provided for counterbalancing vibrations of an axially reciprocating machine. The balance system includes a support member, a flexure assembly, a counterbalance mass, and a linear motor or an actuator. The support member is configured for attachment to the machine. The flexure assembly includes at least one flat spring having connections along a central portion and an outer peripheral portion. One of the central portion and the outer peripheral portion is fixedly mounted to the support member. The counterbalance mass is fixedly carried by the flexure assembly along another of the central portion and the outer peripheral portion. The linear motor has one of a stator and a mover fixedly mounted to the support member and another of the stator and the mover fixedly mounted to the counterbalance mass. The linear motor is operative to axially reciprocate the counterbalance mass.

  2. Central Valley Judicial Relief Act of 2013

    THOMAS, 113th Congress

    Rep. Valadao, David G. [R-CA-21

    2013-08-02

    House - 09/13/2013 Referred to the Subcommittee on Courts, Intellectual Property, and the Internet. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  3. Active vibration and balance system for closed cycle thermodynamic machines

    NASA Technical Reports Server (NTRS)

    Augenblick, John E. (Inventor); Peterson, Allen A. (Inventor); White, Maurice A. (Inventor); Qiu, Songgang (Inventor)

    2004-01-01

    An active balance system is provided for counterbalancing vibrations of an axially reciprocating machine. The balance system includes a support member, a flexure assembly, a counterbalance mass, and a linear motor or an actuator. The support member is configured for attachment to the machine. The flexure assembly includes at least one flat spring having connections along a central portion and an outer peripheral portion. One of the central portion and the outer peripheral portion is fixedly mounted to the support member. The counterbalance mass is fixedly carried by the flexure assembly along another of the central portion and the outer peripheral portion. The linear motor has one of a stator and a mover fixedly mounted to the support member and another of the stator and the mover fixedly mounted to the counterbalance mass. The linear motor is operative to axially reciprocate the counterbalance mass. A method is also provided.

  4. Unsettled weather across central Australia

    NASA Image and Video Library

    2017-12-08

    In late July 2013, a low pressure system off Australia’s southeast coast and moist onshore winds combined to create unsettled weather across central Australia – and a striking image of a broad cloud band across the stark winter landscape. The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard NASA’s Terra satellite captured this true-color image on July 22 at 01:05 UTC (10:35 a.m. Australian Central Standard Time). To the west of the low pressure trough the skies are clear and dry. To the east, the broad band of bright white clouds obscures the landscape. The system brought wind, precipitation and cooler temperatures to the region. The same day as MODIS captured this image, the Naval Research Lab (NRL) published an edition of the Global Storm Tracker (GST), which gave a world-wide view of the low-pressure systems across the world. This tracker shows the entire cloud band across Australia, as well as the location of the low pressure system. A good view of the Storm Tracker is provided by Red Orbit at: www.redorbit.com/media/uploads/2013/07/072213-weather-003... Credit: NASA/GSFC/Jeff Schmaltz/MODIS Land Rapid Response Team NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  5. Aircraft engine with inter-turbine engine frame supported counter rotating low pressure turbine rotors

    NASA Technical Reports Server (NTRS)

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

    2003-01-01

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

  6. Segmented Mirror Image Degradation Due to Surface Dust, Alignment and Figure

    NASA Technical Reports Server (NTRS)

    Schreur, Julian J.

    1999-01-01

    In 1996 an algorithm was developed to include the effects of surface roughness in the calculation of the point spread function of a telescope mirror. This algorithm has been extended to include the effects of alignment errors and figure errors for the individual elements, and an overall contamination by surface dust. The final algorithm builds an array for a guard-banded pupil function of a mirror that may or may not have a central hole, a central reflecting segment, or an outer ring of segments. The central hole, central reflecting segment, and outer ring may be circular or polygonal, and the outer segments may have trimmed comers. The modeled point spread functions show that x-tilt and y-tilt, or the corresponding R-tilt and theta-tilt for a segment in an outer ring, is readily apparent for maximum wavefront errors of 0.1 lambda. A similar sized piston error is also apparent, but integral wavelength piston errors are not. Severe piston error introduces a focus error of the opposite sign, so piston could be adjusted to compensate for segments with varying focal lengths. Dust affects the image principally by decreasing the Strehl ratio, or peak intensity of the image. For an eight-meter telescope a 25% coverage by dust produced a scattered light intensity of 10(exp -9) of the peak intensity, a level well below detectability.

  7. Dynamical evolution of V-type photometric candidates in the central and outer main belt asteroids

    NASA Astrophysics Data System (ADS)

    Carruba, V.; Huaman, M.

    2014-07-01

    V-type asteroids are associated with basaltic composition, and are supposed to be fragments of crust of differentiated objects. Most V-type asteroids in the main belt are found in the inner main belt, and are either current members of the Vesta dynamical family (Vestoids), or past members that drifted away. However, several V-type photometric candidates have been recently identified in the central and outer main belt. The origin of this large population of V-type objects is not well understood, since it seems unlikely that Vestoids crossing the 3:1 and 5:2 mean-motion resonance with Jupiter could account for the whole observed population. In this work, we investigated a possible origin of the bodies from local sources, such as the parent bodies of the Eunomia, Merxia, and Agnia asteroid families in the central main belt, and Dembowska, Eos and Magnya asteroid families in the outer main belt. Our results show that dynamical evolution from the parent bodies of the Eunomia and Merxia/Agnia families on timescales of 2 Gyr or more could be responsible for the current orbital location of most of the V-type photometric candidates in the central main belt. Studies for the outer main belt are currently in progress. by the FAPESP (grant 2011/19863-3) and CAPES (grant 15029-12-3) funding agencies.

  8. Central Texas Water Recycling Act of 2009

    THOMAS, 111th Congress

    Rep. Edwards, Chet [D-TX-17

    2009-02-23

    Senate - 04/27/2010 Committee on Energy and Natural Resources Subcommittee on Water and Power. Hearings held. (All Actions) Tracker: This bill has the status Passed HouseHere are the steps for Status of Legislation:

  9. Fuel cell with electrolyte feed system

    DOEpatents

    Feigenbaum, Haim

    1984-01-01

    A fuel cell having a pair of electrodes at the sites of electrochemical reactions of hydrogen and oxygen and a phosphoric acid electrolyte provided with an electrolyte supporting structure in the form of a laminated matrix assembly disposed between the electrodes. The matrix assembly is formed of a central layer disposed between two outer layers, each being permeable to the flow of the electrolyte. The central layer is provided with relatively large pores while the outer layers are provided with relatively small pores. An external reservoir supplies electrolyte via a feed means to the central layer to compensate for changes in electrolyte volume in the matrix assembly during the operation of fuel cell.

  10. Performance verification of the CMS Phase-1 Upgrade Pixel detector

    NASA Astrophysics Data System (ADS)

    Veszpremi, V.

    2017-12-01

    The CMS tracker consists of two tracking systems utilizing semiconductor technology: the inner pixel and the outer strip detectors. The tracker detectors occupy the volume around the beam interaction region between 3 cm and 110 cm in radius and up to 280 cm along the beam axis. The pixel detector consists of 124 million pixels, corresponding to about 2 m 2 total area. It plays a vital role in the seeding of the track reconstruction algorithms and in the reconstruction of primary interactions and secondary decay vertices. It is surrounded by the strip tracker with 10 million read-out channels, corresponding to 200 m 2 total area. The tracker is operated in a high-occupancy and high-radiation environment established by particle collisions in the LHC . The current strip detector continues to perform very well. The pixel detector that has been used in Run 1 and in the first half of Run 2 was, however, replaced with the so-called Phase-1 Upgrade detector. The new system is better suited to match the increased instantaneous luminosity the LHC would reach before 2023. It was built to operate at an instantaneous luminosity of around 2×1034 cm-2s-1. The detector's new layout has an additional inner layer with respect to the previous one; it allows for more efficient tracking with smaller fake rate at higher event pile-up. The paper focuses on the first results obtained during the commissioning of the new detector. It also includes challenges faced during the first data taking to reach the optimal measurement efficiency. Details will be given on the performance at high occupancy with respect to observables such as data-rate, hit reconstruction efficiency, and resolution.

  11. Floating nut retention system

    NASA Technical Reports Server (NTRS)

    Charles, J. F.; Theakston, H. A. (Inventor)

    1980-01-01

    A floating nut retention system includes a nut with a central aperture. An inner retainer plate has an opening which is fixedly aligned with the nut aperture. An outer retainer member is formed of a base plate having an opening and a surface adjacent to a surface of the inner retainer plate. The outer retainer member includes a securing mechanism for retaining the inner retainer plate adjacent to the outer retainer member. The securing mechanism enables the inner retainer plate to float with respect to the outer retainer number, while simultaneously forming a bearing surface for inner retainer plate.

  12. Central Oregon Jobs and Water Security Act

    THOMAS, 112th Congress

    Rep. Walden, Greg [R-OR-2

    2011-05-31

    Senate - 06/06/2012 Received in the Senate and Read twice and referred to the Committee on Energy and Natural Resources. (All Actions) Tracker: This bill has the status Passed HouseHere are the steps for Status of Legislation:

  13. STELLATE NONHEREDITARY IDIOPATHIC FOVEOMACULAR RETINOSCHISIS ACCOMPANIED BY CONTRALATERAL PERIPHERAL RETINOSCHISIS.

    PubMed

    Ahmed, Daniel; Stattin, Martin; Glittenberg, Carl; Krebs, Ilse; Ansari-Shahrezaei, Siamak

    2017-01-16

    To present a patient with stellate nonhereditary idiopathic foveomacular retinoschisis on one eye and peripheral retinoschisis without foveal affection on the other eye. A case report with complete workup of family history and clinical examination, including multimodal imaging with optical coherence tomography and angiography, fluorescein angiography, and infrared fundus imaging. Genetic testing for gene mutation XRLS1 was performed. A white woman with unremarkable medical history presented with stellate foveal splitting of the outer plexiform layer on the right eye and peripheral splitting of the outer plexiform layer on both eyes. All known allegeable trigger factors for the existence of a hereditary or acquired foveomacular retinoschisis were ruled out either by clinical presentation or genetic testing. This led to the diagnosis of stellate nonhereditary idiopathic foveomacular retinoschisis with central involvement only present on one eye. Although peripheral schisis of the outer plexiform layer is often concomitant with central splitting in X-linked juvenile retinoschisis, this is the first known report of nonhereditary cleavage of the outer plexiform layer of the peripheral retina without central affection in a patient with documented stellate nonhereditary idiopathic foveomacular retinoschisis on the other eye. These findings suggest an accurate bilateral examination of the peripheral retina while confirming the diagnose of stellate nonhereditary idiopathic foveomacular retinoschisis.

  14. Centralized and decentralized global outer-synchronization of asymmetric recurrent time-varying neural network by data-sampling.

    PubMed

    Lu, Wenlian; Zheng, Ren; Chen, Tianping

    2016-03-01

    In this paper, we discuss outer-synchronization of the asymmetrically connected recurrent time-varying neural networks. By using both centralized and decentralized discretization data sampling principles, we derive several sufficient conditions based on three vector norms to guarantee that the difference of any two trajectories starting from different initial values of the neural network converges to zero. The lower bounds of the common time intervals between data samples in centralized and decentralized principles are proved to be positive, which guarantees exclusion of Zeno behavior. A numerical example is provided to illustrate the efficiency of the theoretical results. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Optical power splitter and polarization splitter

    NASA Technical Reports Server (NTRS)

    Bogert, Gail A. (Inventor)

    1988-01-01

    A 3.times.3 optical guiding arrangement is disclosed for providing both power splitting between a pair of output guides in the 3.times.3 guide structure and polarization splitting (into the TE and TM modes) between the central guide and the pair of outer guides. In accordance with the present invention, the mutual coupling length L and separation distance d between adjacent guides are chosen to provide the desired polarization splitting and total intensity (power) in the outer guides. For example, an input signal of intensity I comprising both the TE and TM modes may be launched in the center guide and with correct choices for L and d, will result in output signals of I.sub.TM /2 each of the outer pair of guides and I.sub.TE from the central guide.

  16. Mechanical studies towards a silicon micro-strip super module for the ATLAS inner detector upgrade at the high luminosity LHC

    NASA Astrophysics Data System (ADS)

    Barbier, G.; Cadoux, F.; Clark, A.; Endo, M.; Favre, Y.; Ferrere, D.; Gonzalez-Sevilla, S.; Hanagaki, K.; Hara, K.; Iacobucci, G.; Ikegami, Y.; Jinnouchi, O.; La Marra, D.; Nakamura, K.; Nishimura, R.; Perrin, E.; Seez, W.; Takubo, Y.; Takashima, R.; Terada, S.; Todome, K.; Unno, Y.; Weber, M.

    2014-04-01

    It is expected that after several years of data-taking, the Large Hadron Collider (LHC) physics programme will be extended to the so-called High-Luminosity LHC, where the instantaneous luminosity will be increased up to 5 × 1034 cm-2 s-1. For the general-purpose ATLAS experiment at the LHC, a complete replacement of its internal tracking detector will be necessary, as the existing detector will not provide the required performance due to the cumulated radiation damage and the increase in the detector occupancy. The baseline layout for the new ATLAS tracker is an all-silicon-based detector, with pixel sensors in the inner layers and silicon micro-strip detectors at intermediate and outer radii. The super-module (SM) is an integration concept proposed for the barrel strip region of the future ATLAS tracker, where double-sided stereo silicon micro-strip modules (DSM) are assembled into a low-mass local support (LS) structure. Mechanical aspects of the proposed LS structure are described.

  17. Central Idaho Economic Development and Recreation Act

    THOMAS, 111th Congress

    Sen. Crapo, Mike [R-ID

    2010-04-30

    Senate - 06/16/2010 Committee on Energy and Natural Resources Subcommittee on Public Lands and Forests. Hearings held. With printed Hearing: S.Hrg. 111-730. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  18. Self-Organization of Zonal Jets in Outer Planet Atmospheres: Uranus and Neptune

    NASA Technical Reports Server (NTRS)

    Friedson, A. James

    1997-01-01

    The statistical mechnical theory of a two-dimensional Euler fluid is appleid for the first time to explore the spontaneous self-oganization of zonal jets in outer planet atmospheres. Globally conserved integralls of motion are found to play a central role in defining jet structure.

  19. Avian inhalation exposure chamber

    DOEpatents

    Briant, James K.; Driver, Crystal J.

    1992-01-01

    An exposure system for delivering gaseous material ranging in particle size from 0.4 micrometers to 20.0 micrometers uniformly to the heads of experimental animals, primarily birds. The system includes a vertical outer cylinder and a central chimney with animal holding bottles connected to exposure ports on the vertical outer cylinder.

  20. Congratulating North Central College on winning the 2009 NCAA Division III men's cross country championship.

    THOMAS, 111th Congress

    Rep. Biggert, Judy [R-IL-13

    2010-01-12

    House - 02/23/2010 Referred to the Subcommittee on Higher Education, Lifelong Learning, and Competitiveness. (All Actions) Tracker: This bill has the status Agreed to in HouseHere are the steps for Status of Legislation:

  1. Quality Control Studies of Wavelength Shifting Fibers for a Scintillator-Based Tail Catcher Muon Tracker for Linear Collider Prototype Detector

    NASA Astrophysics Data System (ADS)

    Dyshkant, A.; Beznosko, D.; Blazey, G.; Fisk, E.; Hahn, E.; Rykalin, V.; Wayne, M.; Zutshi, V.

    2006-12-01

    Detailed measurements of the wavelength shifting fiber response to a stable and reliable light source are presented. Particulars about materials, a double reference method, and measurement technique are included. The fibers studied were several hundred Kuraray, Y-11, multiclad, 1.2-mm outer diameter wavelength shifting fibers, each cut from a reel to about one meter length. The fibers were polished, mirrored, and the mirrors were UV epoxy protected. Each fiber passed quality control requirements before installation. About 94% of the fibers tested have a response within 1% of the overall mean

  2. A bill to make technical corrections to the Western and Central Pacific Fisheries Convention Implementation Act, and for other purposes.

    THOMAS, 111th Congress

    Sen. Inouye, Daniel K. [D-HI

    2009-12-10

    Senate - 09/20/2010 Placed on Senate Legislative Calendar under General Orders. Calendar No. 574. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  3. 78 FR 9731 - Gulf of Mexico, Outer Continental Shelf (OCS), Central Planning Area (CPA) Oil and Gas Lease Sale...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-11

    ... Environmental Impact Statement (Multisale FEIS). Authority: This NOA is published pursuant to the regulations... the NEPA process. The Multisale FEIS evaluated the environmental and socioeconomic impacts for CPA... DEPARTMENT OF THE INTERIOR Bureau of Ocean Energy Management Gulf of Mexico, Outer Continental...

  4. Avian inhalation exposure chamber

    DOEpatents

    Briant, J.K.; Driver, C.J.

    1992-05-05

    An exposure system is designed for delivering gaseous material ranging in particle size from 0.4 micrometers to 20.0 micrometers uniformly to the heads of experimental animals, primarily birds. The system includes a vertical outer cylinder and a central chimney with animal holding bottles connected to exposure ports on the vertical outer cylinder. 2 figs.

  5. Side wire feed for welding apparatus

    NASA Technical Reports Server (NTRS)

    Arnett, J. C.

    1974-01-01

    Coaxial electrode arrangement has solid central electrode, insulated outer electrode, and transverse channel for feeding wire through tip of electrode assembly. Polymeric insulation is thrust aside by pressure, which is provided by separately operated mechanism acting through central electrode.

  6. Concentric retinitis pigmentosa: clinicopathologic correlations.

    PubMed

    Milam, A H; De Castro, E B; Smith, J E; Tang, W X; John, S K; Gorin, M B; Stone, E M; Aguirre, G D; Jacobson, S G

    2001-10-01

    Progressive concentric (centripetal) loss of vision is one pattern of visual field loss in retinitis pigmentosa. This study provides the first clinicopathologic correlations for this form of retinitis pigmentosa. A family with autosomal dominant concentric retinitis pigmentosa was examined clinically and with visual function tests. A post-mortem eye of an affected 94 year old family member was processed for histopathology and immunocytochemistry with retinal cell specific antibodies. Unrelated simplex/multiplex patients with concentric retinitis pigmentosa were also examined. Affected family members of the eye donor and patients from the other families had prominent peripheral pigmentary retinopathy with more normal appearing central retina, good visual acuity, concentric field loss, normal or near normal rod and cone sensitivity within the preserved visual field, and reduced rod and cone electroretinograms. The eye donor, at age 90, had good acuity and function in a central island. Grossly, the central region of the donor retina appeared thinned but otherwise normal, while the far periphery contained heavy bone spicule pigment. Microscopically the central retina showed photoreceptor outer segment shortening and some photoreceptor cell loss. The mid periphery had a sharp line of demarcation where more central photoreceptors were near normal except for very short outer segments and peripheral photoreceptors were absent. Rods and cones showed abrupt loss of outer segments and cell death at this interface. It is concluded that concentric retinitis pigmentosa is a rare but recognizable phenotype with slowly progressive photoreceptor death from the far periphery toward the central retina. The disease is retina-wide but shows regional variation in severity of degeneration; photoreceptor death is severe in the peripheral retina with an abrupt edge between viable and degenerate photoreceptors. Peripheral to central gradients of unknown retinal molecule(s) may be defective or modify photoreceptor degeneration in concentric retinitis pigmentosa.

  7. Permanent-magnet switched-flux machine

    DOEpatents

    Trzynadlowski, Andrzej M.; Qin, Ling

    2011-06-14

    A permanent-magnet switched-flux (PMSF) device has an outer rotor mounted to a shaft about a central axis extending axially through the PMSF device. First and second pluralities of permanent-magnets (PMs) are respectively mounted in first and second circles, radially outwardly in first and second transverse planes extending from first and second sections of the central axis adjacent to an inner surface of the outer rotor. An inner stator is coupled to the shaft and has i) a stator core having a core axis co-axial with the central axis; and ii) first and second pluralities of stator poles mounted in first and second circles, radially outwardly from the stator core axis in the first and second transverse planes. The first and second pluralities of PMs each include PMs of alternating polarity.

  8. Permanent-magnet switched-flux machine

    DOEpatents

    Trzynadlowski, Andrzej M.; Qin, Ling

    2012-02-21

    A permanent-magnet switched-flux (PMSF) device has an outer rotor mounted to a shaft about a central axis extending axially through the PMSF device. First and second pluralities of permanent-magnets (PMs) are respectively mounted in first and second circles, radially outwardly in first and second transverse planes extending from first and second sections of the central axis adjacent to an inner surface of the outer rotor. An inner stator is coupled to the shaft and has i) a stator core having a core axis co-axial with the central axis; and ii) first and second pluralities of stator poles mounted in first and second circles, radially outwardly from the stator core axis in the first and second transverse planes. The first and second pluralities of PMs each include PMs of alternating polarity.

  9. Ethnic Enclave Residence, Employment, and Commuting of Latino Workers

    ERIC Educational Resources Information Center

    Liu, Cathy Yang

    2009-01-01

    This paper examines the impact of living in ethnic enclaves in different parts of a metropolitan area on low-skilled Latino immigrants' employment accessibility. It does so by comparing the employment status and commuting times of Latinos living in and out of ethnic neighborhoods in central city, inner-ring suburbs, and outer-ring suburbs in…

  10. Cooperation of Pd-1 and LAG-3 contributes to T-cell exhaustion in anaplasma marginale-infected cattle

    USDA-ARS?s Scientific Manuscript database

    The CD4+ T-cell response is central for control of Anaplasma marginale infection in cattle. However, the infection induces a functional exhaustion of antigen-specific CD4+ T cells in cattle immunized with A. marginale outer membrane proteins or purified outer membranes (OM), which presumably facilit...

  11. A resolution honoring Dr. James Schlesinger, former Secretary of Defense, Secretary of Energy, and Director of Central Intelligence.

    THOMAS, 113th Congress

    Sen. Sessions, Jeff [R-AL

    2014-06-11

    Senate - 06/11/2014 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (All Actions) Tracker: This bill has the status Agreed to in SenateHere are the steps for Status of Legislation:

  12. Impact of the LHC beam abort kicker prefire on high luminosity insertion and CMS detector performance

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

    A.I. Drozhdin, N.V. Mokhov and M. Huhtinen

    1999-04-13

    The effect of possible accidental beam loss in LHC on the IP5 insertion elements and CMS detector is studied via realistic Monte Carlo simulations. Such beam loss could be the consequence of an unsynchronized abort or in worst case an accidental prefire of one of the abort kicker modules. Simulations with the STRUCT code show that this beam losses would take place in the IP5 inner and outer triplets. MARS simulations of the hadronic and electro-magnetic cascades induced in such an event indicate severe heating of the inner triplet quadrupoles. In order to protect the IP5 elements, two methods aremore » proposed: a set of shadow collimators in the outer triplet and a prefired module compensation using a special module charged with an opposite voltage (antikicker). The remnants of the accidental beam loss entering the experimental hall have been used as input for FLUKA simulations in the CMS detector. It is shown that it is vital to take measures to reliably protect the expensive CMS tracker components.« less

  13. Depleted fully monolithic CMOS pixel detectors using a column based readout architecture for the ATLAS Inner Tracker upgrade

    NASA Astrophysics Data System (ADS)

    Wang, T.; Barbero, M.; Berdalovic, I.; Bespin, C.; Bhat, S.; Breugnon, P.; Caicedo, I.; Cardella, R.; Chen, Z.; Degerli, Y.; Egidos, N.; Godiot, S.; Guilloux, F.; Hemperek, T.; Hirono, T.; Krüger, H.; Kugathasan, T.; Hügging, F.; Marin Tobon, C. A.; Moustakas, K.; Pangaud, P.; Schwemling, P.; Pernegger, H.; Pohl, D.-L.; Rozanov, A.; Rymaszewski, P.; Snoeys, W.; Wermes, N.

    2018-03-01

    Depleted monolithic active pixel sensors (DMAPS), which exploit high voltage and/or high resistivity add-ons of modern CMOS technologies to achieve substantial depletion in the sensing volume, have proven to have high radiation tolerance towards the requirements of ATLAS in the high-luminosity LHC era. DMAPS integrating fast readout architectures are currently being developed as promising candidates for the outer pixel layers of the future ATLAS Inner Tracker, which will be installed during the phase II upgrade of ATLAS around year 2025. In this work, two DMAPS prototype designs, named LF-Monopix and TJ-Monopix, are presented. LF-Monopix was fabricated in the LFoundry 150 nm CMOS technology, and TJ-Monopix has been designed in the TowerJazz 180 nm CMOS technology. Both chips employ the same readout architecture, i.e. the column drain architecture, whereas different sensor implementation concepts are pursued. The paper makes a joint description of the two prototypes, so that their technical differences and challenges can be addressed in direct comparison. First measurement results for LF-Monopix will also be shown, demonstrating for the first time a fully functional fast readout DMAPS prototype implemented in the LFoundry technology.

  14. Trapping in irradiated p +-n-n - silicon sensors at fluences anticipated at the HL-LHC outer tracker

    DOE PAGES

    Adam, W.

    2016-04-22

    The degradation of signal in silicon sensors is studied under conditions expected at the CERN High-Luminosity LHC. 200μm thick n-type silicon sensors are irradiated with protons of different energies to fluences of up to 3 x 10 15 neq/cm 2. Pulsed red laser light with a wavelength of 672 nm is used to generate electron-hole pairs in the sensors. The induced signals are used to determine the charge collection efficiencies separately for electrons and holes drifting through the sensor. The effective trapping rates are extracted by comparing the results to simulation. The electric field is simulated using Synopsys device simulationmore » assuming two effective defects. The generation and drift of charge carriers are simulated in an independent simulation based on PixelAV. The effective trapping rates are determined from the measured charge collection efficiencies and the simulated and measured time-resolved current pulses are compared. Furthermore, the effective trapping rates determined for both electrons and holes are about 50% smaller than those obtained using standard extrapolations of studies at low fluences and suggests an improved tracker performance over initial expectations.« less

  15. Autofluorescence from the outer retina and subretinal space: hypothesis and review.

    PubMed

    Spaide, Richard

    2008-01-01

    To review the pathophysiologic principles underlying increased autofluorescence from the outer retina and subretinal space using selected diseases as examples. The ocular imaging information and histopathologic features, when known, were integrated for diseases causing increased autofluorescence from the outer retina and subretinal space. Inferences were taken from this information and used to create a classification scheme. These diseases are principally those that cause separation of the outer retina from the retinal pigment epithelium, thereby preventing proper phagocytosis of photoreceptor outer segments. The separation can arise from increased exudation into the subretinal space or inadequate removal of fluid from the subretinal space. Lack of normal outer segment processing initially leads to increased accumulation of outer segments on the outer retina and subretinal space. Over time, this material is visible as an increasingly thick coating on the outer retina, is yellow, and is autofluorescent. Over time, atrophy develops with thinning of the deposited material and decreasing autofluorescence. The accumulated material is ultimately capable of inducing damage to the retinal pigment epithelium. Diseases causing accumulation of the material include central serous chorioretinopathy, vitelliform macular dystrophy, acute exudative polymorphous vitelliform maculopathy, choroidal tumors, and vitreomacular traction syndrome. The physical separation of the retinal outer segments from the retinal pigment epithelium hinders proper phagocytosis of the outer segments. Accumulation of the shed but not phagocytized outer segments plays a role in disease manifestations for a number of macular diseases.

  16. Assembly Platform For Use In Outer Space

    NASA Technical Reports Server (NTRS)

    Rao, Niranjan S.; Buddington, Patricia A.

    1995-01-01

    Report describes conceptual platform or framework for use in assembling other structures and spacecraft in outer space. Consists of three fixed structural beams comprising central beam and two cross beams. Robotic manipulators spaced apart on platform to provide telerobotic operation of platform by either space-station or ground crews. Platform and attached vehicles function synergistically to achieve maximum performance for intended purposes.

  17. Possible existence of wormholes in the central regions of halos

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

    Rahaman, Farook, E-mail: rahaman@iucaa.ernet.in; Salucci, P., E-mail: salucci@sissa.it; INFN, Sezione di Trieste, Via Valerio 2, 34127, Trieste

    2014-11-15

    An earlier study (Rahaman, et al., 2014 and Kuhfittig, 2014) has demonstrated the possible existence of wormholes in the outer regions of the galactic halo, based on the Navarro–Frenk–White (NFW) density profile. This paper uses the Universal Rotation Curve (URC) dark matter model to obtain analogous results for the central parts of the halo. This result is an important compliment to the earlier result, thereby confirming the possible existence of wormholes in most of the spiral galaxies. - Highlights: • Earlier we showed possible existence of wormholes in the outer regions of halo. • We obtain here analogous results for themore » central parts of the galactic halo. • Our result is an important compliment to the earlier result. • This confirms possible existence of wormholes in most of the spiral galaxies.« less

  18. Imaging performance of annular apertures. IV - Apodization and point spread functions. V - Total and partial energy integral functions

    NASA Technical Reports Server (NTRS)

    Tschunko, H. F. A.

    1983-01-01

    Reference is made to a study by Tschunko (1979) in which it was discussed how apodization modifies the modulation transfer function for various central obstruction ratios. It is shown here how apodization, together with the central obstruction ratio, modifies the point spread function, which is the basic element for the comparison of imaging performance and for the derivation of energy integrals and other functions. At high apodization levels and lower central obstruction (less than 0.1), new extended radial zones are formed in the outer part of the central ring groups. These transmutation of the image functions are of more than theoretical interest, especially if the irradiance levels in the outer ring zones are to be compared to the background irradiance levels. Attention is then given to the energy distribution in point images generated by annular apertures apodized by various transmission functions. The total energy functions are derived; partial energy integrals are determined; and background irradiance functions are discussed.

  19. 76 FR 14040 - Outer Continental Shelf (OCS), Central and Western Gulf of Mexico, Oil and Gas Lease Sales for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-15

    ... Program for 2012-2017. Ten lease sales are specifically covered by this Call: five in the Central GOM... multisale Environmental Impact Statement (EIS) covering the same ten sales in the Central and Western GOM Planning Areas. For each of the ten individual lease sales associated with this Call, BOEMRE will comply...

  20. GPS-based Microenvironment Tracker (MicroTrac) Model to Estimate Time-Location of Individuals for Air Pollution Exposure Assessments: Model Evaluation in Central North Carolina

    EPA Science Inventory

    A critical aspect of air pollution exposure assessment is the estimation of the time spent by individuals in various microenvironments (ME). Accounting for the time spent in different ME with different pollutant concentrations can reduce exposure misclassifications, while failure...

  1. To provide for the establishment of the Special Envoy to Promote Religious Freedom of Religious Minorities in the Near East and South Central Asia.

    THOMAS, 112th Congress

    Rep. Wolf, Frank R. [R-VA-10

    2011-01-25

    Senate - 01/23/2012 Read the second time. Placed on Senate Legislative Calendar under General Orders. Calendar No. 292. (All Actions) Tracker: This bill has the status Passed HouseHere are the steps for Status of Legislation:

  2. AFEII Analog Front End Board Design Specifications

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

    Rubinov, Paul; /Fermilab

    2005-04-01

    This document describes the design of the 2nd iteration of the Analog Front End Board (AFEII), which has the function of receiving charge signals from the Central Fiber Tracker (CFT) and providing digital hit pattern and charge amplitude information from those charge signals. This second iteration is intended to address limitations of the current AFE (referred to as AFEI in this document). These limitations become increasingly deleterious to the performance of the Central Fiber Tracker as instantaneous luminosity increases. The limitations are inherent in the design of the key front end chips on the AFEI board (the SVXIIe and themore » SIFT) and the architecture of the board itself. The key limitations of the AFEI are: (1) SVX saturation; (2) Discriminator to analog readout cross talk; (3) Tick to tick pedestal variation; and (4) Channel to channel pedestal variation. The new version of the AFE board, AFEII, addresses these limitations by use of a new chip, the TriP-t and by architectural changes, while retaining the well understood and desirable features of the AFEI board.« less

  3. Tornado type wind turbines

    DOEpatents

    Hsu, Cheng-Ting

    1984-01-01

    A tornado type wind turbine has a vertically disposed wind collecting tower with spaced apart inner and outer walls and a central bore. The upper end of the tower is open while the lower end of the structure is in communication with a wind intake chamber. An opening in the wind chamber is positioned over a turbine which is in driving communication with an electrical generator. An opening between the inner and outer walls at the lower end of the tower permits radially flowing air to enter the space between the inner and outer walls while a vertically disposed opening in the wind collecting tower permits tangentially flowing air to enter the central bore. A porous portion of the inner wall permits the radially flowing air to interact with the tangentially flowing air so as to create an intensified vortex flow which exits out of the top opening of the tower so as to create a low pressure core and thus draw air through the opening of the wind intake chamber so as to drive the turbine.

  4. Electrically induced mechanical precompression of ferroelectric plates

    DOEpatents

    Chen, P.J.

    1987-03-02

    A method of electrically inducing mechanical precompression of ferroelectric plate covered with electrodes utilizes the change in strains of the plate as functions of applied electric field. A first field polarizes and laterally shrinks the entire plate. An outer portion of the electrodes are removed, and an opposite field partially depolarizes and expands the central portion of the plate against the shrunk outer portion. 2 figs.

  5. Electrically induced mechanical precompression of ferroelectric plates

    DOEpatents

    Chen, Peter J.

    1987-01-01

    A method of electrically inducing mechanical precompression of a ferroelectric plate covered with electrodes utilizes the change in strains of the plate as functions of applied electric field. A first field polarizes and laterally shrinks the entire plate. An outer portion of the electrodes are removed, and an opposite field partially depolarizes and expands the central portion of the plate against the shrunk outer portion.

  6. 77 FR 4360 - Notice of Availability of the Proposed Notice of Sale for Outer Continental Shelf (OCS) Oil and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-27

    ... Proposed Notice of Sale for Outer Continental Shelf (OCS) Oil and Gas Lease Sale 216/222 in the Central...: Notice of Availability of the Proposed Notice of Sale for Proposed Sale 216/222. SUMMARY: BOEM announces the availability of the proposed Notice of Sale (NOS) for proposed Sale 216/222 in the CPA. This...

  7. Turbine nozzle stage having thermocouple guide tube

    DOEpatents

    Schotsch, Margaret Jones; Kirkpatrick, Francis Lawrence; Lapine, Eric Michael

    2002-01-01

    A guide tube is fixed adjacent opposite ends in outer and inner covers of a nozzle stage segment. The guide tube is serpentine in shape between the outer and inner covers and extends through a nozzle vane. An insert is disposed in the nozzle vane and has apertures to accommodate serpentine portions of the guide tube. Cooling steam is also supplied through chambers of the insert on opposite sides of a central insert chamber containing the guide tube. The opposite ends of the guide tube are fixed to sleeves, in turn fixed to the outer and inner covers.

  8. High-voltage R-F feedthrough bushing

    DOEpatents

    Grotz, G.F.

    1982-09-03

    Described is a multi-element, high voltage radio frequency bushing for transmitting rf energy to an antenna located in a vacuum container. The bushing includes a center conductor of complex geometrical shape, an outer coaxial shield conductor, and a thin-walled hollow truncated cone insulator disposed between central and outer conductors. The shape of the center conductor, which includes a reverse curvature portion formed of a radially inwardly directed shoulder and a convex portion, controls the uniformity of the axial surface gradient on the insulator cone. The outer shield has a first substantially cylindrical portion and a second radially inwardly extending truncated cone portion.

  9. High voltage RF feedthrough bushing

    DOEpatents

    Grotz, Glenn F.

    1984-01-01

    Described is a multi-element, high voltage radio frequency bushing for trmitting RF energy to an antenna located in a vacuum container. The bushing includes a center conductor of complex geometrical shape, an outer coaxial shield conductor, and a thin-walled hollow truncated cone insulator disposed between central and outer conductors. The shape of the center conductor, which includes a reverse curvature portion formed of a radially inwardly directed shoulder and a convex portion, controls the uniformity of the axial surface gradient on the insulator cone. The outer shield has a first substantially cylindrical portion and a second radially inwardly extending truncated cone portion.

  10. Histologic development of the human fovea from midgestation to maturity.

    PubMed

    Hendrickson, Anita; Possin, Daniel; Vajzovic, Lejla; Toth, Cynthia A

    2012-11-01

    To describe the histologic development of the human central retina from fetal week (Fwk) 22 to 13 years. Retrospective observational case series. Retinal layers and neuronal substructures were delineated on foveal sections of fixed tissue stained in azure II-methylene blue and on frozen sections immunolabeled for cone, rod, or glial proteins. Postmortem tissue was from 11 eyes at Fwk 20-27; 8 eyes at Fwk 28-37; 6 eyes at postnatal 1 day to 6 weeks; 3 eyes at 9 to 15 months; and 5 eyes at 28 months to 13 years. At Fwk 20-22 the fovea could be identified by the presence of a single layer of cones in the outer nuclear layer. Immunolabeling detected synaptic proteins, cone and rod opsins, and Müller glial processes separating the photoreceptors. The foveal pit appeared at Fwk 25, involving progressive peripheral displacement of ganglion cell, inner plexiform, and inner nuclear layers. The pit became wider and shallower after birth, and appeared mature by 15 months. Between Fwk 25 and Fwk 38, all photoreceptors developed more distinct inner and outer segments, but these were longer on peripheral than foveal cones. After birth the foveal outer nuclear layer became much thicker as cone packing occurred. Cone packing and neuronal migration during pit formation combined to form long central photoreceptor axons, which changed the outer plexiform layer from a thin sheet of synaptic pedicles into the thickest layer in the central retina by 15 months. Foveal inner and outer segment length matched peripheral cones by 15 months and was 4 times longer by 13 years. These data are necessary to understand the marked changes in human retina from late gestation to early adulthood. They provide qualitative and quantitative morphologic information required to interpret the changes in hyper- and hyporeflexive bands in pediatric spectral-domain optical coherence tomography images at the same ages. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. Quantification of photoreceptor layer thickness in different macular pathologies using ultrahigh-resolution optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Drexler, Wolfgang; Hermann, Boris; Unterhuber, Angelika; Sattmann, Harald; Wirtitsch, Matthias; Stur, Michael; Scholda, Christoph; Ergun, Erdem; Anger, Elisabeth; Ko, Tony H.; Schubert, Christian; Ahnelt, Peter K.; Fujimoto, James G.; Fercher, Adolf F.

    2004-07-01

    In vivo ultrahigh resolution ophthalmic OCT has been performed in more than 300 eyes of 200 patients with several retinal pathologies, demonstrating unprecedented visualization of all major intraretinal layers, in particular the photoreceptor layer. Visualization as well as quantification of the inner and outer segment of the photoreceptor layer especially in the foveal region has been acvhieved. In normal subjects the photoreceptor layer thickness in the center of the fovea is about of 90 μm, approximately equally distributed to the inner and the outer photoreceptor segment. In the parafoveal region this thickness is reduced to ~50 μm (~30 μm for the inner and ~20 μm for the outer segment). This is in good agreement with well known increase of cone outer segments in the central foveal region. Photoreceptor layer impairment in different macular pathologies like macular hole, central serous chorioretinopathy, age related macular degeneration, foveomacular dystrophies, Stargardt dystrophy as well as retinitis pigmentosa has been investigated. Photoreceptor layer loss significantly correlated with visual acuity (R2 = 0.6, p < 0.001) and microperimetry findings for the first time in 22 eyes with Stargardt dystrophy. Visualization and quantification of photoreceptor inner and outer segment using ultrahigh resolution OCT has the potential to improve early ophthalmic diagnosis, contributes to a better understanding of pathogenesis of retinal diseases as well as might have impact in the development and monitoring of novel therapy approaches.

  12. The evolution of forearc structures along an oblique convergent margin, central Aleutian Arc

    USGS Publications Warehouse

    Ryan, H.F.; Scholl, D. W.

    1989-01-01

    Multichannel seismic reflection data were used to determine the evolutionary history of the forearc region of the central Aleutian Ridge. Since at least late Miocene time this sector of the ridge has been obliquely underthrust 30?? west of orthogonal convergence by the northwestward converging Pacific plate at a rate of 80-90 km/m.y. Our data indicate that prior to late Eocene time the forearc region was composed of rocks of the arc massif thinly mantled by slope deposits. Beginning in latest Miocene or earliest Pliocene time, a zone of outer-arc structural highs and a forearc basin began to form. Initial structures of the zone of outer-arc highs formed as the thickening wedge underran, compressively deformed, and uplifted the seaward edge of the arc massive above a landward dipping backstop thrust. Forearc basin strata ponded arcward of the elevating zone of outer-arc highs. However, most younger structures of the zone of outer-arc highs cannot be ascribed simply to the orthogonal effects of an underrunning wedge. Oblique convergence created a major right-lateral shear zone (the Hawley Ridge shear zone) that longitudinally disrupted the zone of outer-arc highs, truncating the seaward flank of the forearc basin and shearing the southern limb of Hawley Ridge, an exceptionally large antiformal outer-arc high structure. Uplift of Hawley Ridge may be related to the thickening of the arc massif by westward directed basement duplexes. Great structural complexity, including the close juxtaposition of coeval structures recording compression, extension, differential vertical movements, and strike-slip displacement, should be expected, even within areas of generally kindred tectonostratigraphic terranes. -from Authors

  13. Stellar populations, stellar masses and the formation of galaxy bulges and discs at z < 3 in CANDELS

    NASA Astrophysics Data System (ADS)

    Margalef-Bentabol, Berta; Conselice, Christopher J.; Mortlock, Alice; Hartley, Will; Duncan, Kenneth; Kennedy, Rebecca; Kocevski, Dale D.; Hasinger, Guenther

    2018-02-01

    We present a multicomponent structural analysis of the internal structure of 1074 high-redshift massive galaxies at 1 < z < 3 from the CANDELS HST Survey. In particular, we examine galaxies best fitted by two structural components, and thus likely forming discs and bulges. We examine the stellar mass, star formation rates (SFRs) and colours of both the inner 'bulge' and outer 'disc' components for these systems using Spectral Energy Distribution (SED) information from the resolved ACS+WFC3 HST imaging. We find that the majority of both inner and outer components lie in the star-forming region of UVJ space (68 and 90 per cent, respectively). However, the inner portions, or the likely forming bulges, are dominated by dusty star formation. Furthermore, we show that the outer components of these systems have a higher SFR than their inner regions, and the ratio of SFR between 'disc' and 'bulge' increases at lower redshifts. Despite the higher SFR of the outer component, the stellar mass ratio of inner to outer component remains constant through this epoch. This suggests that there is mass transfer from the outer to inner components for typical two-component-forming systems, thus building bulges from discs. Finally, using Chandra data we find that the presence of an active galactic nucleus is more common in both one-component spheroid-like galaxies and two-component systems (13 ± 3 and 11 ± 2 per cent) than in one-component disc-like galaxies (3 ± 1 per cent), demonstrating that the formation of a central inner component likely triggers the formation of central massive black holes in these galaxies.

  14. To authorize the Secretary of Agriculture to enter into a lease involving the South Central Agricultural Laboratory in Clay County, Nebraska, to facilitate the improvement of the laboratory to support cooperative State and Federal agricultural research.

    THOMAS, 113th Congress

    Rep. Fortenberry, Jeff [R-NE-1

    2014-03-14

    House - 04/01/2014 Referred to the Subcommittee on Department Operations, Oversight, and Nutrition. (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  15. A resolution expressing the condolences of the Senate to those affected by the tragic events following the tornado that hit central Mississippi on April 24, 2010.

    THOMAS, 111th Congress

    Sen. Wicker, Roger F. [R-MS

    2010-04-28

    Senate - 04/28/2010 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (All Actions) Tracker: This bill has the status Agreed to in SenateHere are the steps for Status of Legislation:

  16. A search for minor bodies in the Jovian tenuous ring system

    NASA Astrophysics Data System (ADS)

    Malinnikova Bang, A.; Joergensen, J. L.; Connerney, J. E.; Benn, M.; Denver, T.; Oliversen, R. J.; Lawton, P.

    2013-12-01

    The magnetometer experiment on the Juno spacecraft, is equipped with four fully autonomous star trackers, which apart from delivering highly accurate attitude information for the magnetometer sensors, and the inherent imaging capabilities of a low light camera system, also can detect and track luminous objects that exhibit an apparent motion rate relative to the background. The Juno magnetometer star trackers are pointed 13deg of the spacecraft anti-spin vector, each having a field of view of 13 by 18 degrees and operated at 4Hz. As the spacecraft spin, each camera will cover an annulus shaped disk with an inner radius of 7.5 degrees, and an outer radius of 20.5deg. When in science orbit, the Juno trajectory near peri-jove, will result in the anti-spin vector scanning across the tenuous rings. The combination of this scanning motion with the rotation of the camera field of view results in a near perfect opportunity to detect and track minor bodies in the inner part of the rings. The operations of this mode, is first tested in flight during the Juno Earth Flyby 9th October 2013, where the Moon is used as a known target. We present a few results of this test, and based on scale laws we will discuss the systems capability of detecting minor bodies in the Jovian ring system in terms of distance, velocity, albedo and range. Also, because the magnetometer star trackers are offset from the spin axis, the distance to a detected object can be derived by simple triangulation of the apparent direction as observed before, under and after passage under the rings. We discuss how this technique may be used to determine the orbit, size and albedo, of minor bodies thus detected and tracked.

  17. Expandable space frames

    NASA Technical Reports Server (NTRS)

    Schoen, A. H. (Inventor)

    1973-01-01

    Expandable space frames having essentially infinite periodicity limited only by practical considerations, are described. Each expandable space frame comprises a plurality of hinge joint assemblies having arms that extend outwardly in predetermined symmetrically related directions from a central or vertex point. The outer ends of the arms form one part of a hinge point. The outer expandable space frame also comprises a plurality of struts. The outer ends of the struts from the other part of the hinged joint. The struts interconnect the plurality of hinge point in sychronism, the spaceframes can be expanded or collapsed. Three-dimensional as well as two-dimensional spaceframes of this general nature are described.

  18. Single molecule tracking fluorescence microscopy in mitochondria reveals highly dynamic but confined movement of Tom40

    NASA Astrophysics Data System (ADS)

    Kuzmenko, Anton; Tankov, Stoyan; English, Brian P.; Tarassov, Ivan; Tenson, Tanel; Kamenski, Piotr; Elf, Johan; Hauryliuk, Vasili

    2011-12-01

    Tom40 is an integral protein of the mitochondrial outer membrane, which as the central component of the Translocase of the Outer Membrane (TOM) complex forms a channel for protein import. We characterize the diffusion properties of individual Tom40 molecules fused to the photoconvertable fluorescent protein Dendra2 with millisecond temporal resolution. By imaging individual Tom40 molecules in intact isolated yeast mitochondria using photoactivated localization microscopy with sub-diffraction limited spatial precision, we demonstrate that Tom40 movement in the outer mitochondrial membrane is highly dynamic but confined in nature, suggesting anchoring of the TOM complex as a whole.

  19. Spiral cooled fuel nozzle

    DOEpatents

    Fox, Timothy; Schilp, Reinhard

    2012-09-25

    A fuel nozzle for delivery of fuel to a gas turbine engine. The fuel nozzle includes an outer nozzle wall and a center body located centrally within the nozzle wall. A gap is defined between an inner wall surface of the nozzle wall and an outer body surface of the center body for providing fuel flow in a longitudinal direction from an inlet end to an outlet end of the fuel nozzle. A turbulating feature is defined on at least one of the central body and the inner wall for causing at least a portion of the fuel flow in the gap to flow transverse to the longitudinal direction. The gap is effective to provide a substantially uniform temperature distribution along the nozzle wall in the circumferential direction.

  20. The design of the JUNO veto system

    NASA Astrophysics Data System (ADS)

    Lu, H.; Baussan, E.; experiment, JUNO

    2017-09-01

    The Jiangmen Underground Neutrino Observatory (JUNO) is a multipurpose 20 kton liquid scintillator detector. The detector will be built in a 700 m deep underground laboratory, and its primary physics goal will be to determine the neutrino mass hierarchy. Due to the low background requirement of the experiment, a multi-veto system for cosmic muon detection and background reduction is designed. The volume outside the central detector is filled with pure water and equipped with 2000 MCP-PMTs (20 inches) to form a water Cherenkov detector for muon tagging. A Top Tracker system will be built by re-using the Target Tracker plastic scintillator modules of the OPERA experiment and will cover half of the top area. This will provide valuable information for cosmic muon induced 9Li/8He study.

  1. Progress status for the Mu2e calorimeter system

    DOE PAGES

    Pezzullo, Gianantonio; Budagov, J.; Carosi, R.; ...

    2015-02-13

    The Mu2e experiment at FNAL aims to measure the charged-lepton flavor violating neutrinoless conversion of a negative muon into an electron. The conversion results in a monochromatic electron with an energy slightly below the muon rest mass (104.97 MeV). The calorimeter should confirm that the candidates reconstructed by the extremely precise tracker system are indeed conversion electrons while performing a powerfulmore » $$\\mu/e$$ particle identification. Moreover, it should also provide a high level trigger for the experiment independently from the tracker system. The calorimeter should also be able to keep functionality in an environment where the background delivers a dose of ~ 10 krad/year in the hottest area and to work in the presence of 1 T axial magnetic field. These requirements translate in the design of a calorimeter with large acceptance, good energy resolution O(5%) and a reasonable position (time) resolution of ~<1 cm (<0.5ns). The baseline version of the calorimeter is composed by two disks of inner (outer) radius of 351 (660) mm filled by 1860 hexagonal $$BaF_2$$ crystals of 20 cm length. Each crystal is readout by two large area APD's. In this study, we summarize the experimental tests done so far as well as the simulation studies in the Mu2e environment.« less

  2. STRUCTURAL ASSESSMENT OF HYPERAUTOFLUORESCENT RING IN PATIENTS WITH RETINITIS PIGMENTOSA

    PubMed Central

    LIMA, LUIZ H.; CELLA, WENER; GREENSTEIN, VIVIENNE C.; WANG, NAN-KAI; BUSUIOC, MIHAI; THEODORE SMITH, R.; YANNUZZI, LAWRENCE A.; TSANG, STEPHEN H.

    2009-01-01

    Purpose To analyze the retinal structure underlying the hyperautofluorescent ring visible on fundus autofluorescence in patients with retinitis pigmentosa. Methods Twenty-four eyes of 13 patients with retinitis pigmentosa, aged 13 years to 67 years, were studied. The integrity of the photoreceptor cilia, also known as the inner/outer segment junction of the photoreceptors, the outer nuclear layer, and retinal pigment epithelium, was evaluated outside, across, and inside the ring with spectral-domain optical coherence tomography (OCT). Results Inside the foveal area, fundus autofluorescence did not detect abnormalities. Outside the ring, fundus autofluorescence revealed hypoautofluorescence compatible with the photoreceptor/retinal pigment epithelium degeneration. Spectral-domain OCT inside the ring, in the area of normal foveal fundus autofluorescence, revealed an intact retinal structure in all eyes and total retinal thickness values that were within normal limits. Across the ring, inner/outer segment junction disruption was observed and the outer nuclear layer was decreased in thickness in a centrifugal direction in all eyes. Outside the hyperautofluorescent ring, the inner/outer segment junction and the outer nuclear layer appeared to be absent and there were signs of retinal pigment epithelium degeneration. Conclusion Disruption of the inner/outer segment junction and a decrease in outer retinal thickness were found across the central hyperautofluorescent ring seen in retinitis pigmentosa. Outer segment phagocytosis by retinal pigment epithelium is necessary for the formation of an hyperautofluorescent ring. PMID:19584660

  3. Vitrectomy for optic disk pit with macular schisis and outer retinal dehiscence.

    PubMed

    Shukla, Dhananjay; Kalliath, Jay; Tandon, Manish; Vijayakumar, Balakrishnan

    2012-07-01

    To describe the outcomes of vitrectomy for optic disc pit-related maculopathy with central outer retinal dehiscence. This prospective interventional case series included seven patients with optic disc pit with macular schisis and central outer retinal dehiscence who underwent vitrectomy with internal limiting membrane peeling, barrage laser photocoagulation, and gas tamponade and were followed for at least 6 months. The surgical outcomes in terms of restoration of macular anatomy and visual improvement were recorded at each visit by fundus photography and optical coherence tomography. The mean age of the patients was 21.3 ± 8.6 years (range, 10-35 years), and the mean duration of defective vision was 6.7 ± 8.5 months (range, 1-24 months). Preoperatively, the median best-corrected visual acuity (BCVA) was 20/60 (range, 20/40 to 20/120). Full-thickness macular holes were noticed in 4 patients 1 month postoperatively. Gas tamponade was repeated in two patients with large macular holes. By the final follow-up, macular holes had closed and BCVA improved in all patients except one. Final mean central macular thickness was 176.83 ± 55.74 μ, the range being 109 μ to 256 μ. The median postoperative BCVA was 20/30 (range, 20/20 to 20/80). Six of 7 patients (85.7%) had improvement in BCVA postoperatively (mean, +2 lines; range, 1-4 lines). Five patients (71%) achieved a postoperative BCVA of ≥20/30. Best-corrected visual acuity dropped by one line in the patient with persistent macular hole. Vitrectomy with internal limiting membrane peeling can achieve excellent final surgical outcomes in optic pit maculopathy with outer retinal dehiscence despite the potential for macular hole formation.

  4. Simulation of a Dispersive Tsunami due to the 2016 El Salvador-Nicaragua Outer-Rise Earthquake (M w 6.9)

    NASA Astrophysics Data System (ADS)

    Tanioka, Yuichiro; Ramirez, Amilcar Geovanny Cabrera; Yamanaka, Yusuke

    2018-01-01

    The 2016 El Salvador-Nicaragua outer-rise earthquake (M w 6.9) generated a small tsunami observed at the ocean bottom pressure sensor, DART 32411, in the Pacific Ocean off Central America. The dispersive observed tsunami is well simulated using the linear Boussinesq equations. From the dispersive character of tsunami waveform, the fault length and width of the outer-rise event is estimated to be 30 and 15 km, respectively. The estimated seismic moment of 3.16 × 1019 Nm is the same as the estimation in the Global CMT catalog. The dispersive character of the tsunami in the deep ocean caused by the 2016 outer-rise El Salvador-Nicaragua earthquake could constrain the fault size and the slip amount or the seismic moment of the event.

  5. Simulation of a Dispersive Tsunami due to the 2016 El Salvador-Nicaragua Outer-Rise Earthquake ( M w 6.9)

    NASA Astrophysics Data System (ADS)

    Tanioka, Yuichiro; Ramirez, Amilcar Geovanny Cabrera; Yamanaka, Yusuke

    2018-04-01

    The 2016 El Salvador-Nicaragua outer-rise earthquake ( M w 6.9) generated a small tsunami observed at the ocean bottom pressure sensor, DART 32411, in the Pacific Ocean off Central America. The dispersive observed tsunami is well simulated using the linear Boussinesq equations. From the dispersive character of tsunami waveform, the fault length and width of the outer-rise event is estimated to be 30 and 15 km, respectively. The estimated seismic moment of 3.16 × 1019 Nm is the same as the estimation in the Global CMT catalog. The dispersive character of the tsunami in the deep ocean caused by the 2016 outer-rise El Salvador-Nicaragua earthquake could constrain the fault size and the slip amount or the seismic moment of the event.

  6. A resolution concerning the crisis in the Central African Republic and supporting United States and international efforts to end the violence, protect civilians, and address root causes of the conflict.

    THOMAS, 113th Congress

    Sen. Coons, Christopher A. [D-DE

    2014-03-05

    Senate - 03/13/2014 Resolution agreed to in Senate with an amendment and an amended preamble by Unanimous Consent. (All Actions) Tracker: This bill has the status Agreed to in SenateHere are the steps for Status of Legislation:

  7. Fully distributed monitoring architecture supporting multiple trackees and trackers in indoor mobile asset management application.

    PubMed

    Jeong, Seol Young; Jo, Hyeong Gon; Kang, Soon Ju

    2014-03-21

    A tracking service like asset management is essential in a dynamic hospital environment consisting of numerous mobile assets (e.g., wheelchairs or infusion pumps) that are continuously relocated throughout a hospital. The tracking service is accomplished based on the key technologies of an indoor location-based service (LBS), such as locating and monitoring multiple mobile targets inside a building in real time. An indoor LBS such as a tracking service entails numerous resource lookups being requested concurrently and frequently from several locations, as well as a network infrastructure requiring support for high scalability in indoor environments. A traditional centralized architecture needs to maintain a geographic map of the entire building or complex in its central server, which can cause low scalability and traffic congestion. This paper presents a self-organizing and fully distributed indoor mobile asset management (MAM) platform, and proposes an architecture for multiple trackees (such as mobile assets) and trackers based on the proposed distributed platform in real time. In order to verify the suggested platform, scalability performance according to increases in the number of concurrent lookups was evaluated in a real test bed. Tracking latency and traffic load ratio in the proposed tracking architecture was also evaluated.

  8. Low-pressure water-cooled inductively coupled plasma torch

    DOEpatents

    Seliskar, C.J.; Warner, D.K.

    1984-02-16

    An inductively coupled plasma torch is provided which comprises an inner tube, including a sample injection port to which the sample to be tested is supplied and comprising an enlarged central portion in which the plasma flame is confined; an outer tube surrounding the inner tube and containing water therein for cooling the inner tube, the outer tube including a water inlet port to which water is supplied and a water outlet port spaced from the water inlet port and from which water is removed after flowing through the outer tube; and an rf induction coil for inducing the plasma in the gas passing into the tube through the sample injection port. The sample injection port comprises a capillary tube including a reduced diameter orifice, projecting into the lower end of the inner tube. The water inlet is located at the lower end of the outer tube and the rf heating coil is disposed around the outer tube above and adjacent to the water inlet.

  9. Low-pressure water-cooled inductively coupled plasma torch

    DOEpatents

    Seliskar, Carl J.; Warner, David K.

    1988-12-27

    An inductively coupled plasma torch is provided which comprises an inner tube, including a sample injection port to which the sample to be tested is supplied and comprising an enlarged central portion in which the plasma flame is confined; an outer tube surrounding the inner tube and containing water therein for cooling the inner tube, the outer tube including a water inlet port to which water is supplied and a water outlet port spaced from the water inlet port and from which water is removed after flowing through the outer tube; and an r.f. induction coil for inducing the plasma in the gas passing into the tube through the sample injection port. The sample injection port comprises a capillary tube including a reduced diameter orifice, projecting into the lower end of the inner tube. The water inlet is located at the lower end of the outer tube and the r.f. heating coil is disposed around the outer tube above and adjacent to the water inlet.

  10. Flexible Mechanical Conveyors for Regolith Extraction and Transport

    NASA Technical Reports Server (NTRS)

    Walton, Otis R.; Vollmer, Hubert J.

    2013-01-01

    A report describes flexible mechanical conveying systems for transporting fine cohesive regolith under microgravity and vacuum conditions. They are totally enclosed, virtually dust-free, and can include enough flexibility in the conveying path to enable an expanded range of extraction and transport scenarios, including nonlinear drill-holes and excavation of enlarged subsurface openings without large entry holes. The design of the conveyors is a modification of conventional screw conveyors such that the central screw-shaft and the outer housing or conveyingtube have a degree of bending flexibility, allowing the conveyors to become nonlinear conveying systems that can convey around gentle bends. The central flexible shaft is similar to those used in common tools like a weed whacker, consisting of multiple layers of tightly wound wires around a central wire core. Utilization of compliant components (screw blade or outer wall) increases the robustness of the conveying, allowing an occasional oversized particle to pass hough the conveyor without causing a jam or stoppage

  11. The ATCA CABB Line Survey on Centaurus A: Properties of the Molecular Gas from the Dust Lanes to the Central Engine

    NASA Astrophysics Data System (ADS)

    Ott, Juergen; Koribalski, Baerbel; Henkel, Christian; Edwards, Philip; Norris, Ray; Meier, David; Feain, Ilana; Curran, Steve; Martin-Pintado, Jesus; Beelen, Alexandre; Aalto, Susanne; Combes, Francoise; Israel, Frank; Muller, Sebastien; Espada, Daniel; Guelin, Michel; Black, John Harry; V-Trung, Dinh; Impellizzeri, Caterina M. V.; Persson, Carina

    2011-10-01

    Centaurus A with its host NGC5128 is the most nearby radio galaxy. Its molecular spectrum exhibits three prominent features: a) gas that is located in the outer disk and dust lanes, b) absorption lines that are supposedly close to the central AGN, and c) gas in emission from the nucleus. We propose to perform an extensive line survey toward CenA using the exciting new capabilities of CABB. The broad basebands and narrow zoom bands of CABB are ideal to capture the full breath of the CenA spectral features. Our multi-band line observations will allow us to derive the exact physical conditions of each component as well as the chemistry involved. We will therefore obtain a comprehensive view of the physics imprinted on the molecular spectrum of a radio galaxy and its host, reaching from the central supermassive black hole, through the accretion region and the inner disk to the outer dust lanes.

  12. Changes in Retinal and Choroidal Vascular Blood Flow after Oral Sildenafil: An Optical Coherence Tomography Angiography Study.

    PubMed

    Berrones, David; Salcedo-Villanueva, Guillermo; Morales-Cantón, Virgilio; Velez-Montoya, Raul

    2017-01-01

    To describe changes in the retina and choroidal flow by optical coherence tomography angiography (OCT-A) after a single dose of oral sildenafil. A case-control study. Patients in the study group received 50 mg of oral sildenafil. Patients in the control group received a sham pill. Retinal and choroidal images were obtained at baseline (before pill ingestion) and 1 hour after ingestion. Central macular and choroidal thickness, choroidal and outer retina flow, and the retinal and choroidal vascular density were compared using a Mann-Whitney U test. Twenty eyes were enrolled into the study group and 10 eyes in the control group. There was a significant difference in central choroidal thickness and outer retina blood flow between groups after 1 hour of sildenafil ingestion ( p < 0.01). There were no differences in central macular thickness, choroidal flow, and retinal vascular density among groups. A single dose of oral sildenafil increases choroidal thickness, probably due to sildenafil-induced vasodilation.

  13. Changes in Retinal and Choroidal Vascular Blood Flow after Oral Sildenafil: An Optical Coherence Tomography Angiography Study

    PubMed Central

    Berrones, David; Morales-Cantón, Virgilio

    2017-01-01

    Purpose To describe changes in the retina and choroidal flow by optical coherence tomography angiography (OCT-A) after a single dose of oral sildenafil. Method A case-control study. Patients in the study group received 50 mg of oral sildenafil. Patients in the control group received a sham pill. Retinal and choroidal images were obtained at baseline (before pill ingestion) and 1 hour after ingestion. Central macular and choroidal thickness, choroidal and outer retina flow, and the retinal and choroidal vascular density were compared using a Mann-Whitney U test. Results Twenty eyes were enrolled into the study group and 10 eyes in the control group. There was a significant difference in central choroidal thickness and outer retina blood flow between groups after 1 hour of sildenafil ingestion (p < 0.01). There were no differences in central macular thickness, choroidal flow, and retinal vascular density among groups. Conclusions A single dose of oral sildenafil increases choroidal thickness, probably due to sildenafil-induced vasodilation. PMID:29129998

  14. Conventional tree height-diameter relationships significantly overestimate aboveground carbon stocks in the Central Congo Basin.

    PubMed

    Kearsley, Elizabeth; de Haulleville, Thales; Hufkens, Koen; Kidimbu, Alidé; Toirambe, Benjamin; Baert, Geert; Huygens, Dries; Kebede, Yodit; Defourny, Pierre; Bogaert, Jan; Beeckman, Hans; Steppe, Kathy; Boeckx, Pascal; Verbeeck, Hans

    2013-01-01

    Policies to reduce emissions from deforestation and forest degradation largely depend on accurate estimates of tropical forest carbon stocks. Here we present the first field-based carbon stock data for the Central Congo Basin in Yangambi, Democratic Republic of Congo. We find an average aboveground carbon stock of 162 ± 20  Mg  C  ha(-1) for intact old-growth forest, which is significantly lower than stocks recorded in the outer regions of the Congo Basin. The best available tree height-diameter relationships derived for Central Africa do not render accurate canopy height estimates for our study area. Aboveground carbon stocks would be overestimated by 24% if these inaccurate relationships were used. The studied forests have a lower stature compared with forests in the outer regions of the basin, which confirms remotely sensed patterns. Additionally, we find an average soil carbon stock of 111 ± 24  Mg  C  ha(-1), slightly influenced by the current land-use change.

  15. Restoration of outer segments of foveal photoreceptors after resolution of central serous chorioretinopathy.

    PubMed

    Ojima, Yumiko; Tsujikawa, Akitaka; Yamashiro, Kenji; Ooto, Sotaro; Tamura, Hiroshi; Yoshimura, Nagahisa

    2010-01-01

    To study morphologically and functionally the prognosis of damaged outer segments of the foveal photoreceptor layer in eyes with resolved central serous chorioretinopathy (CSC). We studied retrospectively the medical records of 70 patients (74 eyes) with resolved CSC. Optical coherence tomography was used to detect the junctions between inner and outer segments of the photoreceptors (IS/OS) as a hallmark of the integrity of the outer photoreceptor layer. In 53 eyes (71.6%), the IS/OS line was clearly detected beneath the fovea immediately after resolution of the retinal detachment, with good visual acuity (VA). In the remaining 21 eyes (28.4%), however, the foveal IS/OS line could not be detected shortly after resolution of CSC, and VA was variable, ranging from 0.1 to 1.5 (median, 0.9). Of these 21 eyes, 15 had a follow-up examination with OCT, and in four the foveal IS/OS line was not detected at the follow-up and vision in these eyes remained poor. However, nine eyes showed recovery of the foveal IS/OS line during follow-up, and these eyes had substantial visual recovery. Immediately after resolution of active CSC, although the IS/OS line cannot be detected beneath the fovea, it often shows restoration over time, with visual recovery, though in some eyes no restoration takes place and the prognosis remains poor.

  16. Zero-lag synchronization in coupled time-delayed piecewise linear electronic circuits

    NASA Astrophysics Data System (ADS)

    Suresh, R.; Srinivasan, K.; Senthilkumar, D. V.; Raja Mohamed, I.; Murali, K.; Lakshmanan, M.; Kurths, J.

    2013-07-01

    We investigate and report an experimental confirmation of zero-lag synchronization (ZLS) in a system of three coupled time-delayed piecewise linear electronic circuits via dynamical relaying with different coupling configurations, namely mutual and subsystem coupling configurations. We have observed that when there is a feedback between the central unit (relay unit) and at least one of the outer units, ZLS occurs in the two outer units whereas the central and outer units exhibit inverse phase synchronization (IPS). We find that in the case of mutual coupling configuration ZLS occurs both in periodic and hyperchaotic regimes, while in the subsystem coupling configuration it occurs only in the hyperchaotic regime. Snapshots of the time evolution of outer circuits as observed from the oscilloscope confirm the occurrence of ZLS experimentally. The quality of ZLS is numerically verified by correlation coefficient and similarity function measures. Further, the transition to ZLS is verified from the changes in the largest Lyapunov exponents and the correlation coefficient as a function of the coupling strength. IPS is experimentally confirmed using time series plots and also can be visualized using the concept of localized sets which are also corroborated by numerical simulations. In addition, we have calculated the correlation of probability of recurrence to quantify the phase coherence. We have also analytically derived a sufficient condition for the stability of ZLS using the Krasovskii-Lyapunov theory.

  17. Eye movement perimetry in glaucoma.

    PubMed

    Trope, G E; Eizenman, M; Coyle, E

    1989-08-01

    Present-day computerized perimetry is often inaccurate and unreliable owing to the need to maintain central fixation over long periods while repressing the normal response to presentation of peripheral stimuli. We tested a new method of perimetry that does not require prolonged central fixation. During this test eye movements were encouraged on presentation of a peripheral target. Twenty-three eyes were studied with an Octopus perimeter, with a technician monitoring eye movements. The sensitivity was 100% and the specificity 23%. The low specificity was due to the technician's inability to accurately monitor small eye movements in the central 6 degrees field. If small eye movements are monitored accurately with an eye tracker, eye movement perimetry could become an alternative method to standard perimetry.

  18. Reading with peripheral vision: a comparison of reading dynamic scrolling and static text with a simulated central scotoma.

    PubMed

    Harvey, Hannah; Walker, Robin

    2014-05-01

    Horizontally scrolling text is, in theory, ideally suited to enhance viewing strategies recommended to improve reading performance under conditions of central vision loss such as macular disease, although it is largely unproven in this regard. This study investigated if the use of scrolling text produced an observable improvement in reading performed under conditions of eccentric viewing in an artificial scotoma paradigm. Participants (n=17) read scrolling and static text with a central artificial scotoma controlled by an eye-tracker. There was an improvement in measures of reading accuracy, and adherence to eccentric viewing strategies with scrolling, compared to static, text. These findings illustrate the potential benefits of scrolling text as a potential reading aid for those with central vision loss. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. A resolution supporting enhanced maritime security in the Gulf of Guinea and encouraging increased cooperation between the United States and West and Central African countries to fight armed robbery at sea, piracy, and other maritime threats.

    THOMAS, 113th Congress

    Sen. Flake, Jeff [R-AZ

    2013-11-06

    Senate - 01/07/2014 Resolution agreed to in Senate without amendment and with a preamble by Unanimous Consent. (All Actions) Tracker: This bill has the status Agreed to in SenateHere are the steps for Status of Legislation:

  20. A resolution reaffirming the centrality of freedom of expression and press freedom as cornerstones of United States foreign policy and United States efforts to promote individual rights, and for other purposes.

    THOMAS, 111th Congress

    Sen. Kaufman, Edward E. [D-DE

    2010-02-02

    Senate - 02/02/2010 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (All Actions) Tracker: This bill has the status Agreed to in SenateHere are the steps for Status of Legislation:

  1. Formation of the outer layer of the Dictyostelium spore coat depends on the inner-layer protein SP85/PsB.

    PubMed

    Metcalf, Talibah; Kelley, Karen; Erdos, Gregory W; Kaplan, Lee; West, Christopher M

    2003-02-01

    The Dictyostelium spore is surrounded by a 220 microm thick trilaminar coat that consists of inner and outer electron-dense layers surrounding a central region of cellulose microfibrils. In previous studies, a mutant strain (TL56) lacking three proteins associated with the outer layer exhibited increased permeability to macromolecular tracers, suggesting that this layer contributes to the coat permeability barrier. Electron microscopy now shows that the outer layer is incomplete in the coats of this mutant and consists of a residual regular array of punctate electron densities. The outer layer is also incomplete in a mutant lacking a cellulose-binding protein associated with the inner layer, and these coats are deficient in an outer-layer protein and another coat protein. To examine the mechanism by which this inner-layer protein, SP85, contributes to outer-layer formation, various domain fragments were overexpressed in forming spores. Most of these exert dominant negative effects similar to the deletion of outer-layer proteins, but one construct, consisting of a fusion of the N-terminal and Cys-rich C1 domain, induces a dense mat of novel filaments at the surface of the outer layer. Biochemical studies show that the C1 domain binds cellulose, and a combination of site-directed mutations that inhibits its cellulose-binding activity suppresses outer-layer filament induction. The results suggest that, in addition to a previously described early role in regulating cellulose synthesis, SP85 subsequently contributes a cross-bridging function between cellulose and other coat proteins to organize previously unrecognized structural elements in the outer layer of the coat.

  2. FUNDUS AUTOFLUORESCENCE LIFETIMES AND CENTRAL SEROUS CHORIORETINOPATHY.

    PubMed

    Dysli, Chantal; Berger, Lieselotte; Wolf, Sebastian; Zinkernagel, Martin S

    2017-11-01

    To quantify retinal fluorescence lifetimes in patients with central serous chorioretinopathy (CSC) and to identify disease specific lifetime characteristics over the course of disease. Forty-seven participants were included in this study. Patients with central serous chorioretinopathy were imaged with fundus photography, fundus autofluorescence, optical coherence tomography, and fluorescence lifetime imaging ophthalmoscopy (FLIO) and compared with age-matched controls. Retinal autofluorescence was excited using a 473-nm blue laser light and emitted fluorescence light was detected in 2 distinct wavelengths channels (498-560 nm and 560-720 nm). Clinical features, mean retinal autofluorescence lifetimes, autofluorescence intensity, and corresponding optical coherence tomography (OCT) images were further analyzed. Thirty-five central serous chorioretinopathy patients with a mean visual acuity of 78 ETDRS letters (range, 50-90; mean Snellen equivalent: 20/32) and 12 age-matched controls were included. In the acute stage of central serous chorioretinopathy, retinal fluorescence lifetimes were shortened by 15% and 17% in the respective wavelength channels. Multiple linear regression analysis showed that fluorescence lifetimes were significantly influenced by the disease duration (P < 0.001) and accumulation of photoreceptor outer segments (P = 0.03) but independent of the presence or absence of subretinal fluid. Prolonged central macular autofluorescence lifetimes, particularly in eyes with retinal pigment epithelial atrophy, were associated with poor visual acuity. This study establishes that autofluorescence lifetime changes occurring in central serous chorioretinopathy exhibit explicit patterns which can be used to estimate perturbations of the outer retinal layers with a high degree of statistical significance.

  3. Microfabricated linear Paul-Straubel ion trap

    DOEpatents

    Mangan, Michael A [Albuquerque, NM; Blain, Matthew G [Albuquerque, NM; Tigges, Chris P [Albuquerque, NM; Linker, Kevin L [Albuquerque, NM

    2011-04-19

    An array of microfabricated linear Paul-Straubel ion traps can be used for mass spectrometric applications. Each ion trap comprises two parallel inner RF electrodes and two parallel outer DC control electrodes symmetric about a central trap axis and suspended over an opening in a substrate. Neighboring ion traps in the array can share a common outer DC control electrode. The ions confined transversely by an RF quadrupole electric field potential well on the ion trap axis. The array can trap a wide array of ions.

  4. 77 FR 29682 - Gulf of Mexico, Outer Continental Shelf, Central Planning Area, Oil and Gas Lease Sale 216/222

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-18

    ... and Gas Lease Sale: 2012 Central Planning Area (CPA) Lease Sale 216/222 Authority: This NOA is... a ROD following the completion of the Final SEIS for CPA Consolidated Lease Sale 216/222, the final... SEIS updates two previous environmental and socioeconomic analyses for CPA Lease Sale 216/222. The GOM...

  5. 77 FR 59223 - Notice of Availability of the Proposed Notice of Sale (NOS) for Central Gulf of Mexico Planning...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-26

    ... Proposed Notice of Sale (NOS) for Central Gulf of Mexico Planning Area (CPA) Outer Continental Shelf (OCS) Oil and Gas Lease Sale 227 (CPA Sale 227) AGENCY: Bureau of Ocean Energy Management, Interior. ACTION: Notice of Availability of the Proposed Notice of CPA Sale 227. SUMMARY: BOEM announces the availability...

  6. 78 FR 64243 - Notice of Availability of the Proposed Notice of Sale (NOS) for Central Gulf of Mexico Planning...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-28

    ... of the Proposed Notice of Sale (NOS) for Central Gulf of Mexico Planning Area (CPA) Outer Continental Shelf (OCS) Oil and Gas Lease Sale 231 (CPA Sale 231) AGENCY: Bureau of Ocean Energy Management, Interior. ACTION: Notice of Availability of the Proposed Notice of CPA Sale 231. SUMMARY: BOEM announces...

  7. CORE SHAPES AND ORIENTATIONS OF CORE-SÉRSIC GALAXIES

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

    Dullo, Bililign T.; Graham, Alister W., E-mail: Bdullo@astro.swin.edu.au

    2015-01-01

    The inner and outer shapes and orientations of core-Sérsic galaxies may hold important clues to their formation and evolution. We have therefore measured the central and outer ellipticities and position angles for a sample of 24 core-Sérsic galaxies using archival Hubble Space Telescope (HST) images and data. By selecting galaxies with core-Sérsic break radii R{sub b} —a measure of the size of their partially depleted core—that are ≳ 0.''2, we find that the ellipticities and position angles are quite robust against HST seeing. For the bulk of the galaxies, there is a good agreement between the ellipticities and position anglesmore » at the break radii and the average outer ellipticities and position angles determined over R {sub e}/2 < R < R {sub e}, where R {sub e} is the spheroids' effective half light radius. However there are some interesting differences. We find a median ''inner'' ellipticity at R{sub b} of ε{sub med} = 0.13 ± 0.01, rounder than the median ellipticity of the ''outer'' regions ε{sub med} = 0.20 ± 0.01, which is thought to reflect the influence of the central supermassive black hole at small radii. In addition, for the first time we find a trend, albeit weak (2σ significance), such that galaxies with larger (stellar deficit-to-supermassive black hole) mass ratios—thought to be a measure of the number of major dry merger events—tend to have rounder inner and outer isophotes, suggesting a connection between the galaxy shapes and their merger histories. We show that this finding is not simply reflecting the well known result that more luminous galaxies are rounder, but it is no doubt related.« less

  8. Results from the OH-PT model: a Kinetic-MHD Model of the Outer Heliosphere within SWMF

    NASA Astrophysics Data System (ADS)

    Michael, A.; Opher, M.; Tenishev, V.; Borovikov, D.; Toth, G.

    2017-12-01

    We present an update of the OH-PT model, a kinetic-MHD model of the outer heliosphere. The OH-PT model couples the Outer Heliosphere (OH) and Particle Tracker (PT) components within the Space Weather Modeling Framework (SWMF). The OH component utilizes the Block-Adaptive Tree Solarwind Roe-type Upwind Scheme (BATS-R-US) MHD code, a highly parallel, 3D, and block-adaptive solver. As a stand-alone model, the OH component solves the ideal MHD equations for the plasma and a separate set of Euler's equations for the different populations of neutral atoms. The neutrals and plasma in the outer heliosphere are coupled through charge-exchange. While this provides an accurate solution for the plasma, it is an inaccurate description of the neutrals. The charge-exchange mean free path is on the order of the size of the heliosphere; therefore the neutrals cannot be described as a fluid. The PT component is based on the Adaptive Mesh Particle Simulator (AMPS) model, a 3D, direct simulation Monte Carlo model that solves the Boltzmann equation for the motion and interaction of multi-species plasma and is used to model the neutral distribution functions throughout the domain. The charge-exchange process occurs within AMPS, which handles each event on a particle-by-particle basis and calculates the resulting source terms to the MHD equations. The OH-PT model combines the MHD solution for the plasma with the kinetic solution for the neutrals to form a self-consistent model of the heliosphere. In this work, we present verification and validation of the model as well as demonstrate the codes capabilities. Furthermore we provide a comparison of the OH-PT model to our multi-fluid approximation and detail the differences between the models in both the plasma solution and neutral distribution functions.

  9. Natural History of the Central Structural Abnormalities in Choroideremia: A Prospective Cross-Sectional Study.

    PubMed

    Aleman, Tomas S; Han, Grace; Serrano, Leona W; Fuerst, Nicole M; Charlson, Emily S; Pearson, Denise J; Chung, Daniel C; Traband, Anastasia; Pan, Wei; Ying, Gui-Shuang; Bennett, Jean; Maguire, Albert M; Morgan, Jessica I W

    2017-03-01

    To describe in detail the central retinal structure of a large group of patients with choroideremia (CHM). A prospective, cross-sectional, descriptive study. Patients (n = 97, age 6-71 years) with CHM and subjects with normal vision (n = 44; ages 10-50 years) were included. Subjects were examined with spectral-domain optical coherence tomography (SD OCT) and near-infrared reflectance imaging. Visual acuity (VA) was measured during their encounter or obtained from recent ophthalmic examinations. Visual thresholds were measured in a subset of patients (n = 24) with automated static perimetry within the central regions (±15°) examined with SD OCT. Visual acuity and visual thresholds; total nuclear layer, inner nuclear layer (INL), and outer nuclear layer (ONL) thicknesses; and horizontal extent of the ONL and the photoreceptor outer segment (POS) interdigitation zone (IZ). Earliest abnormalities in regions with normally appearing retinal pigment epithelium (RPE) were the loss of the POS and ellipsoid zone associated with rod dysfunction. Transition zones (TZs) from relatively preserved retina to severe ONL thinning and inner retinal thickening moved centripetally with age. Most patients (88%) retained VAs better than 20/40 until their fifth decade of life. The VA decline coincided with migration of the TZ near the foveal center. There were outer retinal tubulations in degenerated, nonatrophic retina in the majority (69%) of patients. In general, RPE abnormalities paralleled photoreceptor degeneration, although there were regions with detectable but abnormally thin ONL co-localizing with severe RPE depigmentation and choroidal thinning. Abnormalities of the POS and rod dysfunction are the earliest central abnormalities observed in CHM. Foveal function is relatively preserved until the fifth decade of life. Migration of the TZs to the foveal center with foveal thinning and structural disorganization heralded central VA loss. The relationships established may help outline the eligibility criteria and outcome measures for clinical trials for CHM. Copyright © 2016 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  10. Plasma current start-up by the outer ohmic heating coils in the Saskatchewan TORus Modified (STOR-M) iron core tokamak

    DOE PAGES

    Mitarai, O.; Xiao, C.; McColl, D.; ...

    2015-03-24

    A plasma current up to 15 kA has been driven with outer ohmic heating (OH) coils in the STOR-M iron core tokamak. Even when the inner OH coil is disconnected, the outer OH coils alone can induce the plasma current as primary windings and initial breakdown are even easier in this coil layout. Our results suggest a possibility to use an iron core in a spherical tokamak to start up the plasma current without a central solenoid. Finally, the effect of the iron core saturation on the extension of the discharge pulse length has been estimated for further experiments inmore » the STOR-M tokamak.« less

  11. Plasma current start-up by the outer ohmic heating coils in the Saskatchewan TORus Modified (STOR-M) iron core tokamak

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

    Mitarai, O.; Xiao, C.; McColl, D.

    A plasma current up to 15 kA has been driven with outer ohmic heating (OH) coils in the STOR-M iron core tokamak. Even when the inner OH coil is disconnected, the outer OH coils alone can induce the plasma current as primary windings and initial breakdown are even easier in this coil layout. Our results suggest a possibility to use an iron core in a spherical tokamak to start up the plasma current without a central solenoid. Finally, the effect of the iron core saturation on the extension of the discharge pulse length has been estimated for further experiments inmore » the STOR-M tokamak.« less

  12. An outer arm dynein light chain acts in a conformational switch for flagellar motility

    PubMed Central

    Patel-King, Ramila S.

    2009-01-01

    A system distinct from the central pair–radial spoke complex was proposed to control outer arm dynein function in response to alterations in the mechanical state of the flagellum. In this study, we examine the role of a Chlamydomonas reinhardtii outer arm dynein light chain that associates with the motor domain of the γ heavy chain (HC). We demonstrate that expression of mutant forms of LC1 yield dominant-negative effects on swimming velocity, as the flagella continually beat out of phase and stall near or at the power/recovery stroke switchpoint. Furthermore, we observed that LC1 interacts directly with tubulin in a nucleotide-independent manner and tethers this motor unit to the A-tubule of the outer doublet microtubules within the axoneme. Therefore, this dynein HC is attached to the same microtubule by two sites: via both the N-terminal region and the motor domain. We propose that this γ HC–LC1–microtubule ternary complex functions as a conformational switch to control outer arm activity. PMID:19620633

  13. Mortality Risk Associated With Leaving Home: Recognizing the Relevance of the Built Environment

    PubMed Central

    Lucy, William H.

    2003-01-01

    Objectives. I analyzed traffic fatalities and homicides related to leaving home for routine activities, and considered connections between these fatalities and the built environment. Methods. I analyzed city, county, state, and federal data for traffic fatalities and homicides by strangers for 15 metropolitan areas, and classified deaths as occurring in the central city, in inner suburbs, or in outer suburbs (exurbs). Results. Traffic fatality rates were highest in exurban areas. Combined traffic fatality and homicide-by-stranger rates were higher in some or all outer counties than in central cities or inner suburbs in all of the metropolitan areas studied. Conclusions. Traffic fatalities are largely unrecognized as a danger to be factored into residential location decisions. Land use controls that deter sprawl along narrow exurban roads can reduce the mortality risks associated with leaving home. PMID:12948981

  14. Quantification of Peripapillary Sparing and Macular Involvement in Stargardt Disease (STGD1)

    PubMed Central

    Rhee, David W.; Smith, R. Theodore; Tsang, Stephen H.; Allikmets, Rando; Chang, Stanley; Lazow, Margot A.; Hood, Donald C.; Greenstein, Vivienne C.

    2011-01-01

    Purpose. To quantify and compare structure and function across the macula and peripapillary area in Stargardt disease (STGD1). Methods. Twenty-seven patients (27 eyes) and 12 age-similar controls (12 eyes) were studied. Patients were classified on the basis of full-field electroretinogram (ERG) results. Fundus autofluorescence (FAF) and spectral domain-optical coherence tomography (SD-OCT) horizontal line scans were obtained through the fovea and peripapillary area. The thicknesses of the outer nuclear layer plus outer plexiform layer (ONL+), outer segment (OS), and retinal pigment epithelium (RPE) were measured through the fovea, and peripapillary areas from 1° to 4° temporal to the optic disc edge using a computer-aided, manual segmentation technique. Visual sensitivities in the central 10° were assessed using microperimetry and related to retinal layer thicknesses. Results. Compared to the central macula, the differences between controls and patients in ONL+, OS, and RPE layer thicknesses were less in the nasal and temporal macula. Relative sparing of the ONL+ and/or OS layers was detected in the nasal (i.e., peripapillary) macula in 8 of 13 patients with extramacular disease on FAF; relative functional sparing was also detected in this subgroup. All 14 patients with disease confined to the central macula, as detected on FAF, showed ONL+ and OS layer thinning in regions of normal RPE thickness. Conclusions. Relative peripapillary sparing was detected in STGD1 patients with extramacular disease on FAF. Photoreceptor thinning may precede RPE degeneration in STGD1. PMID:21873672

  15. The Distribution of Macular Thickness and Its Determinants in a Healthy Population.

    PubMed

    Hashemi, Hassan; Khabazkhoob, Mehdi; Yekta, AbbasAli; Emamian, Mohammad Hassan; Nabovati, Payam; Fotouhi, Akbar

    2017-10-01

    To determine the distribution of macular thickness in a healthy Iranian population aged 45-69 years and its association with certain determinants. All participants underwent optometric examinations including measurement of uncorrected and corrected visual acuity, objective refraction by retinoscopy, and subjective refraction. Subsequently, all participants underwent slit-lamp biomicroscopy followed by fundus examination through direct and indirect ophthalmoscopy, and optical coherence tomography (OCT) imaging under pupil dilation. Mean central macular thickness was 255.4 µm (95% confidence interval, CI, 254.5-256.3 µm), average inner macular thickness was 316.5 µm (95% CI 315.9-317.1 µm), average outer macular thickness was 275.3 µm (95% CI 274.8-275.8 µm), and overall average thickness was 278.6 µm (95% CI 278.1-279.1 µm). A linear multiple regression model showed that all indexes were significantly larger in male participants (p < 0.001). Central macular thickness increased with age (coef = 0.25, p < 0.001) while overall, inner and outer macular thickness decreased with age (coef = -0.18, -0.15, -0.19, respectively, all p < 0.001). Central and inner macular thickness had a positive correlation (coef = 3.8, 2.6, respectively, both p < 0.001) and outer macular thickness had a negative correlation (coef = -1.6, p < 0.001) with axial length. Age, sex, refractive error, axial length, and keratometry were found to be associated with macular thickness. These factors should be taken into account when interpreting macular thickness measurements with spectral-domain OCT.

  16. Testing the Presence of Multiple Photometric Components in Nearby Early-type Galaxies using SDSS

    NASA Astrophysics Data System (ADS)

    Oh, Semyeong; Greene, Jenny E.; Lackner, Claire N.

    2017-02-01

    We investigate two-dimensional image decomposition of nearby, morphologically selected early-type galaxies (ETGs). We are motivated by recent observational evidence of significant size growth of quiescent galaxies and theoretical development advocating a two-phase formation scenario for ETGs. We find that a significant fraction of nearby ETGs show changes in isophotal shape that require multi-component models. The characteristic sizes of the inner and outer component are ˜3 and ˜15 kpc. The inner component lies on the mass-size relation of ETGs at z ˜ 0.25-0.75, while the outer component tends to be more elliptical and hints at a stochastic buildup process. We find real physical differences between single- and double-component ETGs, with double-component galaxies being younger and more metal-rich. The fraction of double-component ETGs increases with increasing σ and decreases in denser environments. We hypothesize that double-component systems were able to accrete gas and small galaxies until later times, boosting their central densities, building up their outer parts, and lowering their typical central ages. In contrast, the oldest galaxies, perhaps due to residing in richer environments, have no remaining hints of their last accretion episode.

  17. RomA, A Periplasmic Protein Involved in the Synthesis of the Lipopolysaccharide, Tunes Down the Inflammatory Response Triggered by Brucella.

    PubMed

    Valguarnera, Ezequiel; Spera, Juan M; Czibener, Cecilia; Fulgenzi, Fabiana R; Casabuono, Adriana C; Altabe, Silvia G; Pasquevich, Karina A; Guaimas, Francisco; Cassataro, Juliana; Couto, Alicia S; Ugalde, Juan E

    2018-03-28

    Brucellaceae are stealthy pathogens with the ability to survive and replicate in the host in the context of a strong immune response. This capacity relies on several virulence factors that are able to modulate the immune system and in their structural components that have low proinflammatory activities. Lipopolysaccharide (LPS), the main component of the outer membrane, is a central virulence factor of Brucella, and it has been well established that it induces a low inflammatory response. We describe here the identification and characterization of a novel periplasmic protein (RomA) conserved in alpha-proteobacteria, which is involved in the homeostasis of the outer membrane. A mutant in this gene showed several phenotypes, such as membrane defects, altered LPS composition, reduced adhesion, and increased virulence and inflammation. We show that RomA is involved in the synthesis of LPS, probably coordinating part of the biosynthetic complex in the periplasm. Its absence alters the normal synthesis of this macromolecule and affects the homeostasis of the outer membrane, resulting in a strain with a hyperinflammatory phenotype. Our results suggest that the proper synthesis of LPS is central to maximize virulence and minimize inflammation.

  18. Early photoreceptor outer segment loss and retinoschisis in Cohen syndrome.

    PubMed

    Uyhazi, Katherine E; Binenbaum, Gil; Carducci, Nicholas; Zackai, Elaine H; Aleman, Tomas S

    2018-06-01

    To describe early structural and functional retinal changes in a patient with Cohen syndrome. A 13-month-old Caucasian girl of Irish and Spanish ancestry was noted to have micrognathia and laryngomalacia at birth, which prompted a genetic evaluation that revealed biallelic deletions in COH1 (VPS13B) (a maternally inherited 60-kb deletion involving exons 26-32 and a paternally inherited 3.5-kb deletion within exon 17) consistent with Cohen syndrome. She underwent a complete ophthalmic examination, full-field flash electroretinography and retinal imaging with spectral domain optical coherence tomography. Central vision was central, steady, and maintained. There was bilateral myopic astigmatic refractive error. Fundus exam was notable for dark foveolar pigmentation, but no obvious abnormalities of either eye. Spectral domain optical coherence tomography cross sections through the fovea revealed a normal appearing photoreceptor outer nuclear layer but loss of the interdigitation signal between the photoreceptor outer segments and the apical retinal pigment epithelium. Retinoschisis involving the inner nuclear layer of both eyes and possible ganglion cell layer thinning were also noted. There was a detectable electroretinogram with similarly reduced amplitudes of rod- (white, 0.01 cd.s.m -2 ) and cone-mediated (3 cd.s.m -2 , 30 Hz) responses. Photoreceptor outer segment abnormalities and retinoschisis may represent the earliest structural retinal change detected by spectral domain optical coherence tomography in patients with Cohen syndrome, suggesting a complex pathophysiology with primary involvement of the photoreceptor cilium and disorganization of the structural integrity of the inner retina.

  19. SALT, a dedicated readout chip for high precision tracking silicon strip detectors at the LHCb Upgrade

    NASA Astrophysics Data System (ADS)

    Bugiel, Sz.; Dasgupta, R.; Firlej, M.; Fiutowski, T.; Idzik, M.; Kuczynska, M.; Moron, J.; Swientek, K.; Szumlak, T.

    2016-02-01

    The Upstream Tracker (UT) silicon strip detector, one of the central parts of the tracker system of the modernised LHCb experiment, will use a new 128-channel readout ASIC called SALT. It will extract and digitise analogue signals from the UT sensors, perform digital signal processing and transmit a serial output data. The SALT is being designed in CMOS 130 nm process and uses a novel architecture comprising of analog front-end and fast (40 MSps) ultra-low power (<0.5 mW) 6-bit ADC in each channel. The prototype ASICs of important functional blocks, like analogue front-end, 6-bit SAR ADC, PLL, and DLL, were designed, fabricated and tested. A prototype of an 8-channel version of the SALT chip, comprising all important functionalities was also designed and fabricated. The architecture and design of the SALT, together with the selected preliminary tests results, are presented.

  20. To provide for the establishment of the Special Envoy to Promote Religious Freedom of Religious Minorities in the Near East and South Central Asia.

    THOMAS, 113th Congress

    Rep. Wolf, Frank R. [R-VA-10

    2013-01-15

    Senate - 09/19/2013 Received in the Senate and Read twice and referred to the Committee on Foreign Relations. (All Actions) Notes: For further action, see S.653, which became Public Law 113-161 on 8/8/2014. Tracker: This bill has the status Passed HouseHere are the steps for Status of Legislation:

  1. Fully Distributed Monitoring Architecture Supporting Multiple Trackees and Trackers in Indoor Mobile Asset Management Application

    PubMed Central

    Jeong, Seol Young; Jo, Hyeong Gon; Kang, Soon Ju

    2014-01-01

    A tracking service like asset management is essential in a dynamic hospital environment consisting of numerous mobile assets (e.g., wheelchairs or infusion pumps) that are continuously relocated throughout a hospital. The tracking service is accomplished based on the key technologies of an indoor location-based service (LBS), such as locating and monitoring multiple mobile targets inside a building in real time. An indoor LBS such as a tracking service entails numerous resource lookups being requested concurrently and frequently from several locations, as well as a network infrastructure requiring support for high scalability in indoor environments. A traditional centralized architecture needs to maintain a geographic map of the entire building or complex in its central server, which can cause low scalability and traffic congestion. This paper presents a self-organizing and fully distributed indoor mobile asset management (MAM) platform, and proposes an architecture for multiple trackees (such as mobile assets) and trackers based on the proposed distributed platform in real time. In order to verify the suggested platform, scalability performance according to increases in the number of concurrent lookups was evaluated in a real test bed. Tracking latency and traffic load ratio in the proposed tracking architecture was also evaluated. PMID:24662407

  2. 76 FR 82319 - Gulf of Mexico (GOM), Outer Continental Shelf (OCS), Western Planning Area (WPA) and Central...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-30

    ... Continental Shelf (OCS), Western Planning Area (WPA) and Central Planning Area (CPA), Oil and Gas Lease Sales... prepared a Draft EIS on oil and gas lease sales tentatively scheduled in 2012-2017 in the WPA and CPA... scheduled for the WPA and five annual areawide lease sales are scheduled for the CPA. The proposed WPA lease...

  3. Episcleral eye plaque dosimetry comparison for the Eye Physics EP917 using Plaque Simulator and Monte Carlo simulation

    PubMed Central

    Amoush, Ahmad; Wilkinson, Douglas A.

    2015-01-01

    This work is a comparative study of the dosimetry calculated by Plaque Simulator, a treatment planning system for eye plaque brachytherapy, to the dosimetry calculated using Monte Carlo simulation for an Eye Physics model EP917 eye plaque. Monte Carlo (MC) simulation using MCNPX 2.7 was used to calculate the central axis dose in water for an EP917 eye plaque fully loaded with 17 IsoAid Advantage  125I seeds. In addition, the dosimetry parameters Λ, gL(r), and F(r,θ) were calculated for the IsoAid Advantage model IAI‐125  125I seed and benchmarked against published data. Bebig Plaque Simulator (PS) v5.74 was used to calculate the central axis dose based on the AAPM Updated Task Group 43 (TG‐43U1) dose formalism. The calculated central axis dose from MC and PS was then compared. When the MC dosimetry parameters for the IsoAid Advantage  125I seed were compared with the consensus values, Λ agreed with the consensus value to within 2.3%. However, much larger differences were found between MC calculated gL(r) and F(r,θ) and the consensus values. The differences between MC‐calculated dosimetry parameters are much smaller when compared with recently published data. The differences between the calculated central axis absolute dose from MC and PS ranged from 5% to 10% for distances between 1 and 12 mm from the outer scleral surface. When the dosimetry parameters for the  125I seed from this study were used in PS, the calculated absolute central axis dose differences were reduced by 2.3% from depths of 4 to 12 mm from the outer scleral surface. We conclude that PS adequately models the central dose profile of this plaque using its defaults for the IsoAid model IAI‐125 at distances of 1 to 7 mm from the outer scleral surface. However, improved dose accuracy can be obtained by using updated dosimetry parameters for the IsoAid model IAI‐125  125I seed. PACS number: 87.55.K‐ PMID:26699577

  4. Seismic stratigraphy and tomography in the outer shelf and slope of the Central Basin, Ross Sea, Antarctica

    NASA Astrophysics Data System (ADS)

    Kim, Sookwan; De Santis, Laura; Böhm, Gualtiero; Kuk Hong, Jong; Jin, Young Keun; Geletti, Riccardo; Wardell, Nigel; Petronio, Lorenzo; Colizza, Ester

    2014-05-01

    The Ross Sea, located between Victoria Land and Marie Byrd Land in Antarctica, is one of the main drainage of the Antarctic Ice Sheet (AIS). Reflection seismic data acquired by many countries during several decades have provided insights into the history of the Ross Sea and the AIS evolution. However the majority of the existing seismic data are concentrated in the shelf area, where hiatus formed by grounding ice sheet erosion multiple events prevent to reconstruct the entire sedimentary sequences depositional evolution. On the outer shelf and upper slope, the sedimentary sequences are relatively well preserved. The main purpose of this study is the investigation of the Cenozoic Antarctic Ice Sheet evolution through the seismic sequence analysis of the outer shelf and slope of the Central Basin, in the Ross Sea. The data used are the new multi-channel seismic data, KSL12, were acquired on the outer shelf and upper slope of the Central Bain in February 2013 by Korea Polar Research Institute. The reflection seismic data, previously collected by the Italian Antarctic Program (PNRA) and other data available from the Seismic Data Library System (SDLS) are also used for velocity tomography and seismic sequence mapping. The seismic data were processed by a conventional processing flow to produce the seismic profiles. Preliminary results show well-developed prograding wedges at the mouth of glacial troughs, eroded by a major glacial unconformity, the Ross Sea Unconformity 4 (RSU-4), correlated to a main event between early- and mid-Miocene. The velocity anomalies shown along KSL12-1 can be interpreted as showing the occurrence of gas and fluids, diagenetic horizons and sediment compactions. The isopach maps of each sequence show the variation of thickness of the sediments depocenter shift. The seismic sequence stratigraphy and acoustic facies analysis provide information about different phases of ice sheet's advance and retreat related to the AIS Cenozoic dynamics.

  5. FUNDUS AUTOFLUORESCENCE LIFETIMES AND CENTRAL SEROUS CHORIORETINOPATHY

    PubMed Central

    Dysli, Chantal; Berger, Lieselotte; Wolf, Sebastian

    2017-01-01

    Purpose: To quantify retinal fluorescence lifetimes in patients with central serous chorioretinopathy (CSC) and to identify disease specific lifetime characteristics over the course of disease. Methods: Forty-seven participants were included in this study. Patients with central serous chorioretinopathy were imaged with fundus photography, fundus autofluorescence, optical coherence tomography, and fluorescence lifetime imaging ophthalmoscopy (FLIO) and compared with age-matched controls. Retinal autofluorescence was excited using a 473-nm blue laser light and emitted fluorescence light was detected in 2 distinct wavelengths channels (498–560 nm and 560–720 nm). Clinical features, mean retinal autofluorescence lifetimes, autofluorescence intensity, and corresponding optical coherence tomography (OCT) images were further analyzed. Results: Thirty-five central serous chorioretinopathy patients with a mean visual acuity of 78 ETDRS letters (range, 50–90; mean Snellen equivalent: 20/32) and 12 age-matched controls were included. In the acute stage of central serous chorioretinopathy, retinal fluorescence lifetimes were shortened by 15% and 17% in the respective wavelength channels. Multiple linear regression analysis showed that fluorescence lifetimes were significantly influenced by the disease duration (P < 0.001) and accumulation of photoreceptor outer segments (P = 0.03) but independent of the presence or absence of subretinal fluid. Prolonged central macular autofluorescence lifetimes, particularly in eyes with retinal pigment epithelial atrophy, were associated with poor visual acuity. Conclusion: This study establishes that autofluorescence lifetime changes occurring in central serous chorioretinopathy exhibit explicit patterns which can be used to estimate perturbations of the outer retinal layers with a high degree of statistical significance. PMID:28099314

  6. Collaborative emitter tracking using Rao-Blackwellized random exchange diffusion particle filtering

    NASA Astrophysics Data System (ADS)

    Bruno, Marcelo G. S.; Dias, Stiven S.

    2014-12-01

    We introduce in this paper the fully distributed, random exchange diffusion particle filter (ReDif-PF) to track a moving emitter using multiple received signal strength (RSS) sensors. We consider scenarios with both known and unknown sensor model parameters. In the unknown parameter case, a Rao-Blackwellized (RB) version of the random exchange diffusion particle filter, referred to as the RB ReDif-PF, is introduced. In a simulated scenario with a partially connected network, the proposed ReDif-PF outperformed a PF tracker that assimilates local neighboring measurements only and also outperformed a linearized random exchange distributed extended Kalman filter (ReDif-EKF). Furthermore, the novel ReDif-PF matched the tracking error performance of alternative suboptimal distributed PFs based respectively on iterative Markov chain move steps and selective average gossiping with an inter-node communication cost that is roughly two orders of magnitude lower than the corresponding cost for the Markov chain and selective gossip filters. Compared to a broadcast-based filter which exactly mimics the optimal centralized tracker or its equivalent (exact) consensus-based implementations, ReDif-PF showed a degradation in steady-state error performance. However, compared to the optimal consensus-based trackers, ReDif-PF is better suited for real-time applications since it does not require iterative inter-node communication between measurement arrivals.

  7. The Outer Halos of Early-Type Galaxies

    NASA Astrophysics Data System (ADS)

    Gerhard, Ortwin; Arnaboldi, Magda; Longobardi, Alessia

    2015-04-01

    The outer halos of massive early-type galaxies (ETGs) are dark matter dominated and may have formed by accretion of smaller systems during galaxy evolution. Here a brief report is given of some recent work on the kinematics, angular momentum, and mass distributions of simulated ETG halos, and of corresponding properties of observed halos measured with planetary nebulae (PNe) as tracers. In the outermost regions of the Virgo-central galaxy M87, the PN data show that the stellar halo and the co-spatial intracluster light are distinct kinematic components.

  8. Self-organized formation of GaSb/GaAs quantum rings.

    PubMed

    Timm, R; Eisele, H; Lenz, A; Ivanova, L; Balakrishnan, G; Huffaker, D L; Dähne, M

    2008-12-19

    Ring-shaped GaSb/GaAs quantum dots, grown by molecular beam epitaxy, were studied using cross-sectional scanning tunneling microscopy. These quantum rings have an outer shape of a truncated pyramid with baselengths around 15 nm and heights of about 2 nm but are characterized by a clear central opening extending over about 40% of the outer baselength. They form spontaneously during the growth and subsequent continuous capping of GaSb/GaAs quantum dots due to the large strain and substantial As-for-Sb exchange reactions leading to strong Sb segregation.

  9. Ringlight for use in high radiation

    DOEpatents

    Baylor, G.A.; Jacket, H.S.

    1992-09-01

    A ringlight having an annular array of light-emitting elements centered about a viewing passage has an outer annular body with an inner annular body fitted concentrically within the outer body to form an annular void and a light-emitting aperture therebetween. A plurality of optical fibers extends into the void with end portions of the optical fibers secured therein to form an annular array at the light-emitting aperture. The first and second annular bodies cooperate to angle the end portions of the optical fibers towards a central axis of the viewing passage. 3 figs.

  10. Approach guidance for outer planet pioneer missions

    NASA Technical Reports Server (NTRS)

    Bejczy, A. K.

    1975-01-01

    Onboard optical approach guidance measurements for spin-stabilized Pioneer-type spacecraft are discussed. Approach guidance measurement accuracy requirements are outlined. The application concept and operation principle of the V-slit star tracker are discussed within the context of approach guidance measurements and measurables. It is shown that the accuracy of onboard optical approach guidance measurements is inherently coupled to the stability characteristics of the spacecraft spin axis. Geometrical and physical measurement parameters are presented for Pioneer entry probe missions to Uranus via Jupiter or Saturn flyby. The impact of these parameters on both sensor instrumentation and measurement system design is discussed. The need for sensing extended objects is shown. The feasibility of implementing an onboard approach guidance measurement system for Pioneer-type spacecraft is indicated. Two Pioneer 10 onboard measurement experiments performed in May-June 1974 are described.

  11. Sustainably powering wearable electronics solely by biomechanical energy

    PubMed Central

    Wang, Jie; Li, Shengming; Yi, Fang; Zi, Yunlong; Lin, Jun; Wang, Xiaofeng; Xu, Youlong; Wang, Zhong Lin

    2016-01-01

    Harvesting biomechanical energy is an important route for providing electricity to sustainably drive wearable electronics, which currently still use batteries and therefore need to be charged or replaced/disposed frequently. Here we report an approach that can continuously power wearable electronics only by human motion, realized through a triboelectric nanogenerator (TENG) with optimized materials and structural design. Fabricated by elastomeric materials and a helix inner electrode sticking on a tube with the dielectric layer and outer electrode, the TENG has desirable features including flexibility, stretchability, isotropy, weavability, water-resistance and a high surface charge density of 250 μC m−2. With only the energy extracted from walking or jogging by the TENG that is built in outsoles, wearable electronics such as an electronic watch and fitness tracker can be immediately and continuously powered. PMID:27677971

  12. Fixed-Time Outer Synchronization of Complex Networks with Noise Coupling

    NASA Astrophysics Data System (ADS)

    Shi, Hong-Jun; Miao, Lian-Ying; Sun, Yong-Zheng; Liu, Mao-Xing

    2018-03-01

    In this paper, the fixed-time outer synchronization of complex networks with noise coupling is investigated. Based on the theory of fixed-time stability and matrix inequalities, sufficient conditions for fixed-time outer synchronization are established and the estimation of the upper bound of the setting time is obtained. The result shows that the setting time can be adjusted to a desired value regardless of the initial states. Numerical simulations are performed to verify the effectiveness of the theoretical results. The effects of control parameters and the density of controlled nodes on the converging time are studied. Supported by the National Natural Science Foundation of China under Grant Nos. 11711530203 and 11771443, and the Fundamental Research Funds for the Central Universities under Grant No. 2015XKMS076

  13. Solar energy apparatus with apertured shield

    NASA Technical Reports Server (NTRS)

    Collings, Roger J. (Inventor); Bannon, David G. (Inventor)

    1989-01-01

    A protective apertured shield for use about an inlet to a solar apparatus which includesd a cavity receiver for absorbing concentrated solar energy. A rigid support truss assembly is fixed to the periphery of the inlet and projects radially inwardly therefrom to define a generally central aperture area through which solar radiation can pass into the cavity receiver. A non-structural, laminated blanket is spread over the rigid support truss in such a manner as to define an outer surface area and an inner surface area diverging radially outwardly from the central aperture area toward the periphery of the inlet. The outer surface area faces away from the inlet and the inner surface area faces toward the cavity receiver. The laminated blanket includes at least one layer of material, such as ceramic fiber fabric, having high infra-red emittance and low solar absorption properties, and another layer, such as metallic foil, of low infra-red emittance properties.

  14. Method for forming an in situ oil shale retort with horizontal free faces

    DOEpatents

    Ricketts, Thomas E.; Fernandes, Robert J.

    1983-01-01

    A method for forming a fragmented permeable mass of formation particles in an in situ oil shale retort is provided. A horizontally extending void is excavated in unfragmented formation containing oil shale and a zone of unfragmented formation is left adjacent the void. An array of explosive charges is formed in the zone of unfragmented formation. The array of explosive charges comprises rows of central explosive charges surrounded by a band of outer explosive charges which are adjacent side boundaries of the retort being formed. The powder factor of each outer explosive charge is made about equal to the powder factor of each central explosive charge. The explosive charges are detonated for explosively expanding the zone of unfragmented formation toward the void for forming the fragmented permeable mass of formation particles having a reasonably uniformly distributed void fraction in the in situ oil shale retort.

  15. Secretins revealed: structural insights into the giant gated outer membrane portals of bacteria.

    PubMed

    Majewski, Dorothy D; Worrall, Liam J; Strynadka, Natalie Cj

    2018-03-23

    The acquisition and evolution of customized and often highly complex secretion systems allows Gram-negative bacteria to efficiently passage large macromolecules across both inner and outer membranes and, in some cases, that of the infected host. Essential to the virulence and ultimate survival of the many pathogenic species that encode them, secretion systems export a wide variety of effector proteins and DNA as well as the downstream extracellular filaments of the secretion apparatus themselves. Although these customized secretion systems differ in their cytosolic and inner membrane components, several commonly rely on the secretin family of giant pores to allow these large substrates to traverse the outer membrane. Recently, several near-atomic resolution cryo-EM secretin structures have unveiled the first insights into the unique structural motifs required for outer membrane localization, assembly, hallmark ultrastable nature, spontaneous membrane insertion, and mechanism of action-including the requisite central gating needed to prevent deleterious passage of periplasmic contents to the extracellular space. Copyright © 2018. Published by Elsevier Ltd.

  16. In-line quincke tube muffler

    NASA Astrophysics Data System (ADS)

    Patrick, William P.; Bryant, Rebecca S.; Greenwald, Larry E.

    2002-05-01

    A unique low-pressure-drop muffler is described which has been designed to attenuate low frequency tonal noise in ducts. Flow through the muffler is divided into two noncommunicating paths in the cylindrical configuration which was designed, built, and tested. Half of the flow is ducted through a straight central annulus and the other half is ducted through a partitioned outer annulus which directs the flow in a spiral flow pattern around the inner annulus. Thus the outer flow has a longer path length and the sound within the outer annulus is phase-delayed relative to the inner flow causing destructive interference between the inner and outer waves with resulting strong attenuation at the tuned frequencies. A procedure will be described for designing a muffler (with flow) to produce high attenuation at the fundamental noise tone and all harmonics (up to the first cross mode). Results will be presented which show that the muffler achieved over 20 dB attenuation for the first five harmonics of the incident noise in a flowing duct.

  17. To designate the facility of the United States Postal Service located at 787 State Route 17M in Monroe, New York, as the "National Clandestine Service of the Central Intelligence Agency NCS Officer Gregg David Wenzel Memorial Post Office".

    THOMAS, 112th Congress

    Rep. Hayworth, Nan A. S. [R-NY-19

    2011-12-07

    Senate - 08/29/2012 Committee on Homeland Security and Governmental Affairs referred to Subcommittee on Federal Financial Management, Government Information, Federal Services, and International Security. (All Actions) Tracker: This bill has the status Passed HouseHere are the steps for Status of Legislation:

  18. Expressing the sense of Congress on the occasion of the 20th anniversary of historic events in Central and Eastern Europe, particularly the Velvet Revolution in Czechoslovakia, and reaffirming the bonds of friendship and cooperation between the United States and the Slovak Republic and the Czech Republic.

    THOMAS, 111th Congress

    Rep. Mica, John L. [R-FL-7

    2009-11-07

    Senate - 11/20/2009 Received in the Senate and referred to the Committee on Foreign Relations. (All Actions) Tracker: This bill has the status Agreed to in HouseHere are the steps for Status of Legislation:

  19. Particle trap for compressed gas insulated transmission systems

    DOEpatents

    Cookson, A.H.

    1984-04-26

    A particle trap is provided for gas insulated transmission lines having a central high voltage conductor supported within an outer coaxial conductive sheath by a dielectric support member. A cavity between the inner conductor and outer sheath is filled with a dielectric insulating gas. A cone-like particle deflector, mounted to the inner conductor, deflects moving particles away from the support member, to radially outer portions of the cavity. A conductive shield is disposed adjacent the outer sheath to form a field-free region in radially outer portions of the cavity, between the shield and the sheath. Particles traveling along the cavity are deflected by the cone-like deflector into the field-free region where they are held immobile. In a vertical embodiment, particles enter the field-free region through an upper end of a gap formed between shield and sheath members. In a horizontal embodiment, the deflector cone has a base which is terminated radially internally of the shield. Apertures in the shield located adjacent the deflector allow passage of deflected particles into the field-free region. The dielectric support member is thereby protected from contaminating particles that may otherwise come to rest thereon.

  20. Particle trap for compressed gas insulated transmission systems

    DOEpatents

    Cookson, Alan H.

    1985-01-01

    A particle trap is provided for gas insulated transmission lines having a central high voltage conductor supported within an outer coaxial conductive sheath by a dielectric support member. A cavity between the inner conductor and outer sheath is filled with a dielectric insulating gas. A cone-like particle deflector, mounted to the inner conductor, deflects moving particles away from the support member, to radially outer portions of the cavity. A conductive shield is disposed adjacent the outer sheath to form a field-free region in radially outer portions of the cavity, between the shield and the sheath. Particles traveling along the cavity are deflected by the cone-like deflector into the field-free region where they are held immobile. In a vertical embodiment, particles enter the field-free region through an upper end of a gap formed between shield and sheath members. In a horizontal embodiment, the deflector cone has a base which is terminated radially internally of the shield. Apertures in the shield located adjacent the deflector allow passage of deflected particles into the field-free region. The dielectric support member is thereby protected from contaminating particles that may otherwise come to rest thereon.

  1. Preparation of Geophysical Fluid Flow Experiments With The Rotating Spherical Gap Flow Model In Space

    NASA Astrophysics Data System (ADS)

    Egbers, C.

    The'GeoFlow' is an ESA experiment planned for the Fluid Science Laboratory on ISS under the scientific coordination (PI) of the Department of Aerodynamics and Fluid Mechanics (LAS) at the Brandenburg Technical University (BTU) of Cottbus, Germany. The objective of the experiment is to study thermal convection in the gap between two concentric rotating (full) spheres. A central symmetric force field simi- lar to the gravity field acting on planets can be produced by applying a high voltage between inner and outer sphere using the dielectrophoretic effect (rotating capacitor). To counter the unidirectional gravity under terrestrial conditions, this experiment re- quires a microgravity environment. The parameters of the experiment are chosen in analogy to the thermal convective motions in the outer core of the Earth. In analogy to geophysical motions in the Earth`s liquid core the experiment can rotate as solid body as well as differential (inner to outer). Thermal convection is produced by heat- ing the inner sphere and cooling the outer ones. Furtheron, the variation of radius ratio between inner and outer sphere is foreseen as a parameter variation. The flows to be investigated will strongly depend on the gap width and on the Prandtl number.

  2. 77 FR 40081 - Gulf of Mexico, Outer Continental Shelf (OCS), Western Planning Area (WPA) and Central Planning...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-06

    ... environmental impacts resulting from the Deepwater Horizon event, BOEM conducted an extensive search for... events, including a low- probability catastrophic event associated with a proposed lease sale and a...

  3. 75 FR 70023 - Outer Continental Shelf (OCS), Western and Central Planning Areas, Gulf of Mexico (GOM) Oil and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-16

    ..., November 16, 2010, New Orleans, Louisiana, Hilton New Orleans Airport, 901 Airline Drive Kenner, Louisiana... the Regional Supervisor, Leasing and Environment (MS 5410), Bureau of Ocean Energy Management...

  4. DUSTiNGS. III. Distribution of Intermediate-age and Old Stellar Populations in Disks and Outer Extremities of Dwarf Galaxies

    NASA Astrophysics Data System (ADS)

    McQuinn, Kristen B. W.; Boyer, Martha L.; Mitchell, Mallory B.; Skillman, Evan D.; Gehrz, R. D.; Groenewegen, Martin A. T.; McDonald, Iain; Sloan, G. C.; van Loon, Jacco Th.; Whitelock, Patricia A.; Zijlstra, Albert A.

    2017-01-01

    We have traced the spatial distributions of intermediate-age and old stars in nine dwarf galaxies in the distant parts of the Local Group, using multi-epoch 3.6 and 4.5 μm data from the DUST in Nearby Galaxies with Spitzer (DUSTiNGS) survey. Using complementary optical imaging from the Hubble Space Telescope, we identify the tip of the red giant branch (TRGB) in the 3.6 μm photometry, separating thermally pulsating asymptotic giant branch stars from the larger red giant branch populations. Unlike the constant TRGB in the I band, at 3.6 μm, the TRGB magnitude varies by ˜0.7 mag, making it unreliable as a distance indicator. The intermediate-age and old stars are well mixed in two-thirds of the sample, with no evidence of a gradient in the ratio of the intermediate-age to old stellar populations outside the central ˜1‧-2‧. Variable AGB stars are detected in the outer extremities of the galaxies, indicating that chemical enrichment from these dust-producing stars may occur in the outer regions of galaxies with some frequency. Theories of structure formation in dwarf galaxies must account for the lack of radial gradients in intermediate-age populations and the presence of these stars in the outer extremities of dwarfs. Finally, we identify unique features in individual galaxies, such as extended tidal features in Sex A and Sag DIG and a central concentration of AGB stars in the inner regions of NGC 185 and NGC 147.

  5. Spatial Variations of Turbulent Properties of Neutral Hydrogen Gas in the Small Magellanic Cloud Using Structure-function Analysis

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

    Nestingen-Palm, David; Stanimirović, Snežana; González-Casanova, Diego F.

    2017-08-10

    We investigate spatial variations of turbulent properties in the Small Magellanic Cloud (SMC) by using neutral hydrogen (H i) observations. With the goal of testing the importance of stellar feedback on H i turbulence, we define central and outer SMC regions based on the star formation rate (SFR) surface density, as well as the H i integrated intensity. We use the structure function and the velocity channel analysis to calculate the power-law index ( γ ) for both underlying density and velocity fields in these regions. In all cases, our results show essentially no difference in γ between the centralmore » and outer regions. This suggests that H i turbulent properties are surprisingly homogeneous across the SMC when probed at a resolution of 30 pc. Contrary to recent suggestions from numerical simulations, we do not find a significant change in γ due to stellar feedback as traced by the SFR surface density. This could be due to the stellar feedback being widespread over the whole of the SMC, but more likely due to a large-scale gravitational driving of turbulence. We show that the lack of difference between central and outer SMC regions cannot be explained by the high optical depth H I.« less

  6. Identification of minor inner-membrane components of the Shigella type III secretion system 'needle complex'.

    PubMed

    Zenk, Sebastian F; Stabat, David; Hodgkinson, Julie L; Veenendaal, Andreas K J; Johnson, Steven; Blocker, Ariel J

    2007-08-01

    Type III secretion systems (T3SSs or secretons) are central virulence factors of many Gram-negative bacteria, used to inject protein effectors of virulence into eukaryotic host cells. Their overall morphology, consisting of a cytoplasmic region, an inner- and outer-membrane section and an extracellular needle, is conserved in various species. A portion of the secreton, containing the transmembrane regions and needle, has been isolated biochemically and termed the 'needle complex' (NC). However, there are still unsolved questions concerning the nature and relative arrangement of the proteins assembling the NC. Until these are resolved, the mode of function of the NC cannot be clarified. This paper describes an affinity purification method that enables highly efficient purification of Shigella NCs under near-physiological conditions. Using this method, three new minor components of the NC were identified by mass spectrometry: IpaD, a known component of the needle tip complex, and two predicted components of its central inner-membrane export apparatus, Spa40 and Spa24. A further minor component of the NC, MxiM, is only detected by immunoblotting. MxiM is a 'pilotin'-type protein for the outer-membrane 'secretin' ring formed of MxiD. As expected, it localized to the outer rim of the upper ring of NCs, validating the other findings.

  7. Magnetour: Surfing planetary systems on electromagnetic and multi-body gravity fields

    NASA Astrophysics Data System (ADS)

    Lantoine, Gregory; Russell, Ryan P.; Anderson, Rodney L.; Garrett, Henry B.

    2017-09-01

    A comprehensive tour of the complex outer planet systems is a central goal in space science. However, orbiting multiple moons of the same planet would be extremely prohibitive using traditional propulsion and power technologies. In this paper, a new mission concept, named Magnetour, is presented to facilitate the exploration of outer planet systems and address both power and propulsion challenges. This approach would enable a single spacecraft to orbit and travel between multiple moons of an outer planet, without significant propellant or onboard power source. To achieve this free-lunch 'Grand Tour', Magnetour exploits the unexplored combination of magnetic and multi-body gravitational fields of planetary systems, with a unique focus on using a bare electrodynamic tether for power and propulsion. Preliminary results indicate that the Magnetour concept is sound and is potentially highly promising at Jupiter.

  8. Rho-associated protein kinase regulates subcellular localisation of Angiomotin and Hippo-signalling during preimplantation mouse embryo development.

    PubMed

    Mihajlović, Aleksandar I; Bruce, Alexander W

    2016-09-01

    The differential activity of the Hippo-signalling pathway between the outer- and inner-cell populations of the developing preimplantation mouse embryo directs appropriate formation of trophectoderm and inner cell mass (ICM) lineages. Such distinct signalling activity is under control of intracellular polarization, whereby Hippo-signalling is either supressed in polarized outer cells or activated in apolar inner cells. The central role of apical-basolateral polarization to such differential Hippo-signalling regulation prompted us to reinvestigate the role of potential upstream molecular regulators affecting apical-basolateral polarity. This study reports that the chemical inhibition of Rho-associated kinase (Rock) is associated with failure to form morphologically distinct blastocysts, indicative of compromised trophectoderm differentiation, and defects in the localization of both apical and basolateral polarity factors associated with malformation of tight junctions. Moreover, Rock-inhibition mediates mislocalization of the Hippo-signalling activator Angiomotin (Amot), to the basolateral regions of outer cells and is concomitant with aberrant activation of the pathway. The Rock-inhibition phenotype is mediated by Amot, as RNAi-based Amot knockdown totally rescues the normal suppression of Hippo-signalling in outer cells. In conclusion, Rock, via regulating appropriate apical-basolateral polarization in outer cells, regulates the appropriate activity of the Hippo-signalling pathway, by ensuring correct subcellular localization of Amot protein in outer cells. Copyright © 2016 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  9. Imaging performance of annular apertures. II - Line spread functions

    NASA Technical Reports Server (NTRS)

    Tschunko, H. F. A.

    1978-01-01

    Line images formed by aberration-free optical systems with annular apertures are investigated in the whole range of central obstruction ratios. Annular apertures form lines images with central and side line groups. The number of lines in each line group is given by the ratio of the outer diameter of the annular aperture divided by the width of the annulus. The theoretical energy fraction of 0.889 in the central line of the image formed by an unobstructed aperture increases for centrally obstructed apertures to 0.932 for the central line group. Energy fractions for the central and side line groups are practically constant for all obstruction ratios and for each line group. The illumination of rectangular secondary apertures of various length/width ratios by apertures of various obstruction ratios is discussed.

  10. Test beam demonstration of silicon microstrip modules with transverse momentum discrimination for the future CMS tracking detector

    NASA Astrophysics Data System (ADS)

    Adam, W.; Bergauer, T.; Brondolin, E.; Dragicevic, M.; Friedl, M.; Frühwirth, R.; Hoch, M.; Hrubec, J.; König, A.; Steininger, H.; Treberspurg, W.; Waltenberger, W.; Alderweireldt, S.; Beaumont, W.; Janssen, X.; Lauwers, J.; Van Mechelen, P.; Van Remortel, N.; Van Spilbeeck, A.; Beghin, D.; Brun, H.; Clerbaux, B.; De Lentdecker, G.; Delannoy, H.; Fasanella, G.; Favart, L.; Goldouzian, R.; Grebenyuk, A.; Karapostoli, G.; Lenzi, T.; Léonard, A.; Luetic, J.; Maerschalk, T.; Marinov, A.; Postiau, N.; Randle-Conde, A.; Seva, T.; Vanlaer, P.; Vannerom, D.; Yonamine, R.; Wang, Q.; Yang, Y.; Zenoni, F.; Zhang, F.; Abu Zeid, S.; Blekman, F.; De Bruyn, I.; De Clercq, J.; D'Hondt, J.; Deroover, K.; Lowette, S.; Moortgat, S.; Moreels, L.; Python, Q.; Skovpen, K.; Van Mulders, P.; Van Parijs, I.; Bakhshiansohi, H.; Bondu, O.; Brochet, S.; Bruno, G.; Caudron, A.; Delaere, C.; Delcourt, M.; De Visscher, S.; Francois, B.; Giammanco, A.; Jafari, A.; Cabrera Jamoulle, J.; De Favereau De Jeneret, J.; Komm, M.; Krintiras, G.; Lemaitre, V.; Magitteri, A.; Mertens, A.; Michotte, D.; Musich, M.; Piotrzkowski, K.; Quertenmont, L.; Szilasi, N.; Vidal Marono, M.; Wertz, S.; Beliy, N.; Caebergs, T.; Daubie, E.; Hammad, G. H.; Härkönen, J.; Lampén, T.; Luukka, P.; Peltola, T.; Tuominen, E.; Tuovinen, E.; Eerola, P.; Baulieu, G.; Boudoul, G.; Caponetto, L.; Combaret, C.; Contardo, D.; Dupasquier, T.; Gallbit, G.; Lumb, N.; Mirabito, L.; Perries, S.; Vander Donckt, M.; Viret, S.; Agram, J.-L.; Andrea, J.; Bloch, D.; Bonnin, C.; Brom, J.-M.; Chabert, E.; Chanon, N.; Charles, L.; Conte, E.; Fontaine, J.-Ch.; Gross, L.; Hosselet, J.; Jansova, M.; Tromson, D.; Autermann, C.; Feld, L.; Karpinski, W.; Kiesel, K. M.; Klein, K.; Lipinski, M.; Ostapchuk, A.; Pierschel, G.; Preuten, M.; Rauch, M.; Schael, S.; Schomakers, C.; Schulz, J.; Schwering, G.; Wlochal, M.; Zhukov, V.; Pistone, C.; Fluegge, G.; Kuensken, A.; Pooth, O.; Stahl, A.; Aldaya, M.; Asawatangtrakuldee, C.; Beernaert, K.; Bertsche, D.; Contreras-Campana, C.; Eckerlin, G.; Eckstein, D.; Eichhorn, T.; Gallo, E.; Garay Garcia, J.; Hansen, K.; Haranko, M.; Harb, A.; Hauk, J.; Keaveney, J.; Kalogeropoulos, A.; Kleinwort, C.; Lohmann, W.; Mankel, R.; Maser, H.; Mittag, G.; Muhl, C.; Mussgiller, A.; Pitzl, D.; Reichelt, O.; Savitskyi, M.; Schuetze, P.; Walsh, R.; Zuber, A.; Biskop, H.; Buhmann, P.; Centis-Vignali, M.; Garutti, E.; Haller, J.; Hoffmann, M.; Klanner, R.; Matysek, M.; Perieanu, A.; Scharf, Ch.; Schleper, P.; Schmidt, A.; Schwandt, J.; Sonneveld, J.; Steinbrück, G.; Vormwald, B.; Wellhausen, J.; Abbas, M.; Amstutz, C.; Barvich, T.; Barth, Ch.; Boegelspacher, F.; De Boer, W.; Butz, E.; Casele, M.; Colombo, F.; Dierlamm, A.; Freund, B.; Hartmann, F.; Heindl, S.; Husemann, U.; Kornmeyer, A.; Kudella, S.; Muller, Th.; Printz, M.; Simonis, H. J.; Steck, P.; Weber, M.; Weiler, Th.; Anagnostou, G.; Asenov, P.; Assiouras, P.; Daskalakis, G.; Kyriakis, A.; Loukas, D.; Paspalaki, L.; Siklér, F.; Veszprémi, V.; Bhardwaj, A.; Dalal, R.; Jain, G.; Ranjan, K.; Dutta, S.; Chowdhury, S. Roy; Bakhshiansohl, H.; Behnamian, H.; Khakzad, M.; Naseri, M.; Cariola, P.; Creanza, D.; De Palma, M.; De Robertis, G.; Fiore, L.; Franco, M.; Loddo, F.; Sala, G.; Silvestris, L.; Maggi, G.; My, S.; Selvaggi, G.; Albergo, S.; Costa, S.; Di Mattia, A.; Giordano, F.; Potenza, R.; Saizu, M. A.; Tricomi, A.; Tuve, C.; Barbagli, G.; Brianzi, M.; Ciaranfi, R.; Ciulli, V.; Civinini, C.; D'Alessandro, R.; Focardi, E.; Latino, G.; Lenzi, P.; Meschini, M.; Paoletti, S.; Russo, L.; Scarlini, E.; Sguazzoni, G.; Strom, D.; Viliani, L.; Ferro, F.; Lo Vetere, M.; Robutti, E.; Dinardo, M. E.; Fiorendi, S.; Gennai, S.; Malvezzi, S.; Manzoni, R. A.; Menasce, D.; Moroni, L.; Pedrini, D.; Azzi, P.; Bacchetta, N.; Bisello, D.; Dall'Osso, M.; Pozzobon, N.; Tosi, M.; De Canio, F.; Gaioni, L.; Manghisoni, M.; Nodari, B.; Riceputi, E.; Re, V.; Traversi, G.; Comotti, D.; Ratti, L.; Alunni Solestizi, L.; Biasini, M.; Bilei, G. M.; Cecchi, C.; Checcucci, B.; Ciangottini, D.; Fanò, L.; Gentsos, C.; Ionica, M.; Leonardi, R.; Manoni, E.; Mantovani, G.; Marconi, S.; Mariani, V.; Menichelli, M.; Modak, A.; Morozzi, A.; Moscatelli, F.; Passeri, D.; Placidi, P.; Postolache, V.; Rossi, A.; Saha, A.; Santocchia, A.; Storchi, L.; Spiga, D.; Androsov, K.; Azzurri, P.; Arezzini, S.; Bagliesi, G.; Basti, A.; Boccali, T.; Borrello, L.; Bosi, F.; Castaldi, R.; Ciampa, A.; Ciocci, M. A.; Dell'Orso, R.; Donato, S.; Fedi, G.; Giassi, A.; Grippo, M. T.; Ligabue, F.; Lomtadze, T.; Magazzu, G.; Martini, L.; Mazzoni, E.; Messineo, A.; Moggi, A.; Morsani, F.; Palla, F.; Palmonari, F.; Raffaelli, F.; Rizzi, A.; Savoy-Navarro, A.; Spagnolo, P.; Tenchini, R.; Tonelli, G.; Venturi, A.; Verdini, P. G.; Bellan, R.; Costa, M.; Covarelli, R.; Da Rocha Rolo, M.; Demaria, N.; Rivetti, A.; Dellacasa, G.; Mazza, G.; Migliore, E.; Monteil, E.; Pacher, L.; Ravera, F.; Solano, A.; Fernandez, M.; Gomez, G.; Jaramillo Echeverria, R.; Moya, D.; Gonzalez Sanchez, F. J.; Vila, I.; Virto, A. L.; Abbaneo, D.; Ahmed, I.; Albert, E.; Auzinger, G.; Berruti, G.; Bianchi, G.; Blanchot, G.; Bonnaud, J.; Caratelli, A.; Ceresa, D.; Christiansen, J.; Cichy, K.; Daguin, J.; D'Auria, A.; Detraz, S.; Deyrail, D.; Dondelewski, O.; Faccio, F.; Frank, N.; Gadek, T.; Gill, K.; Honma, A.; Hugo, G.; Jara Casas, L. M.; Kaplon, J.; Kornmayer, A.; Kottelat, L.; Kovacs, M.; Krammer, M.; Lenoir, P.; Mannelli, M.; Marchioro, A.; Marconi, S.; Mersi, S.; Martina, S.; Michelis, S.; Moll, M.; Onnela, A.; Orfanelli, S.; Pavis, S.; Peisert, A.; Pernot, J.-F.; Petagna, P.; Petrucciani, G.; Postema, H.; Rose, P.; Tropea, P.; Troska, J.; Tsirou, A.; Vasey, F.; Vichoudis, P.; Verlaat, B.; Zwalinski, L.; Bachmair, F.; Becker, R.; di Calafiori, D.; Casal, B.; Berger, P.; Djambazov, L.; Donega, M.; Grab, C.; Hits, D.; Hoss, J.; Kasieczka, G.; Lustermann, W.; Mangano, B.; Marionneau, M.; Martinez Ruiz del Arbol, P.; Masciovecchio, M.; Meinhard, M.; Perozzi, L.; Roeser, U.; Starodumov, A.; Tavolaro, V.; Wallny, R.; Zhu, D.; Amsler, C.; Bösiger, K.; Caminada, L.; Canelli, F.; Chiochia, V.; de Cosa, A.; Galloni, C.; Hreus, T.; Kilminster, B.; Lange, C.; Maier, R.; Ngadiuba, J.; Pinna, D.; Robmann, P.; Taroni, S.; Yang, Y.; Bertl, W.; Deiters, K.; Erdmann, W.; Horisberger, R.; Kaestli, H.-C.; Kotlinski, D.; Langenegger, U.; Meier, B.; Rohe, T.; Streuli, S.; Chen, P.-H.; Dietz, C.; Grundler, U.; Hou, W.-S.; Lu, R.-S.; Moya, M.; Cussans, D.; Flacher, H.; Goldstein, J.; Grimes, M.; Jacob, J.; Seif El Nasr-Storey, S.; Cole, J.; Hoad, C.; Hobson, P.; Morton, A.; Reid, I. D.; Auzinger, G.; Bainbridge, R.; Dauncey, P.; Fulcher, J.; Hall, G.; James, T.; Magnan, A.-M.; Pesaresi, M.; Raymond, D. M.; Uchida, K.; Braga, D.; Coughlan, J. A.; Harder, K.; Jones, L.; Ilic, J.; Murray, P.; Prydderch, M.; Tomalin, I. R.; Garabedian, A.; Heintz, U.; Narain, M.; Nelson, J.; Sagir, S.; Speer, T.; Swanson, J.; Tersegno, D.; Watson-Daniels, J.; Chertok, M.; Conway, J.; Conway, R.; Flores, C.; Lander, R.; Pellett, D.; Ricci-Tam, F.; Squires, M.; Thomson, J.; Yohay, R.; Burt, K.; Ellison, J.; Hanson, G.; Olmedo, M.; Si, W.; Yates, B. R.; Gerosa, R.; Sharma, V.; Vartak, A.; Yagil, A.; Zevi Della Porta, G.; Dutta, V.; Gouskos, L.; Incandela, J.; Kyre, S.; Mullin, S.; Qu, H.; White, D.; Dominguez, A.; Bartek, R.; Cumalat, J. P.; Ford, W. T.; Jensen, F.; Johnson, A.; Krohn, M.; Leontsinis, S.; Mulholland, T.; Stenson, K.; Wagner, S. R.; Apresyan, A.; Bolla, G.; Burkett, K.; Butler, J. N.; Cheung, H. W. K.; Chramowicz, J.; Christian, D.; Cooper, W. E.; Deptuch, G.; Derylo, G.; Gingu, C.; Grünendahl, S.; Hasegawa, S.; Hoff, J.; Howell, J.; Hrycyk, M.; Jindariani, S.; Johnson, M.; Kahlid, F.; Lei, C. M.; Lipton, R.; Lopes De Sá, R.; Liu, T.; Los, S.; Matulik, M.; Merkel, P.; Nahn, S.; Prosser, A.; Rivera, R.; Schneider, B.; Sellberg, G.; Shenai, A.; Spiegel, L.; Tran, N.; Uplegger, L.; Voirin, E.; Berry, D. R.; Chen, X.; Ennesser, L.; Evdokimov, A.; Evdokimov, O.; Gerber, C. E.; Hofman, D. J.; Makauda, S.; Mills, C.; Sandoval Gonzalez, I. D.; Alimena, J.; Antonelli, L. J.; Francis, B.; Hart, A.; Hill, C. S.; Parashar, N.; Stupak, J.; Bortoletto, D.; Bubna, M.; Hinton, N.; Jones, M.; Miller, D. H.; Shi, X.; Tan, P.; Baringer, P.; Bean, A.; Khalil, S.; Kropivnitskaya, A.; Majumder, D.; Wilson, G.; Ivanov, A.; Mendis, R.; Mitchell, T.; Skhirtladze, N.; Taylor, R.; Anderson, I.; Fehling, D.; Gritsan, A.; Maksimovic, P.; Martin, C.; Nash, K.; Osherson, M.; Swartz, M.; Xiao, M.; Acosta, J. G.; Cremaldi, L. M.; Oliveros, S.; Perera, L.; Summers, D.; Bloom, K.; Claes, D. R.; Fangmeier, C.; Gonzalez Suarez, R.; Monroy, J.; Siado, J.; Hahn, K.; Sevova, S.; Sung, K.; Trovato, M.; Bartz, E.; Gershtein, Y.; Halkiadakis, E.; Kyriacou, S.; Lath, A.; Nash, K.; Osherson, M.; Schnetzer, S.; Stone, R.; Walker, M.; Malik, S.; Norberg, S.; Ramirez Vargas, J. E.; Alyari, M.; Dolen, J.; Godshalk, A.; Harrington, C.; Iashvili, I.; Kharchilava, A.; Nguyen, D.; Parker, A.; Rappoccio, S.; Roozbahani, B.; Alexander, J.; Chaves, J.; Chu, J.; Dittmer, S.; McDermott, K.; Mirman, N.; Rinkevicius, A.; Ryd, A.; Salvati, E.; Skinnari, L.; Soffi, L.; Tao, Z.; Thom, J.; Tucker, J.; Zientek, M.; Akgün, B.; Ecklund, K. M.; Kilpatrick, M.; Nussbaum, T.; Zabel, J.; Betchart, B.; Covarelli, R.; Demina, R.; Hindrichs, O.; Petrillo, G.; Eusebi, R.; Patel, R.; Perloff, A.; Ulmer, K. A.; Delannoy, A. G.; D'Angelo, P.; Johns, W.

    2018-03-01

    A new CMS Tracker is under development for operation at the High Luminosity LHC from 2026 onwards. It includes an outer tracker based on dedicated modules that will reconstruct short track segments, called stubs, using spatially coincident clusters in two closely spaced silicon sensor layers. These modules allow the rejection of low transverse momentum track hits and reduce the data volume before transmission to the first level trigger. The inclusion of tracking information in the trigger decision is essential to limit the first level trigger accept rate. A customized front-end readout chip, the CMS Binary Chip (CBC), containing stub finding logic has been designed for this purpose. A prototype module, equipped with the CBC chip, has been constructed and operated for the first time in a 4 GeemVem/emc positron beam at DESY. The behaviour of the stub finding was studied for different angles of beam incidence on a module, which allows an estimate of the sensitivity to transverse momentum within the future CMS detector. A sharp transverse momentum threshold around 2 emVem/emc was demonstrated, which meets the requirement to reject a large fraction of low momentum tracks present in the LHC environment on-detector. This is the first realistic demonstration of a silicon tracking module that is able to select data, based on the particle's transverse momentum, for use in a first level trigger at the LHC . The results from this test are described here.

  11. Double bowl piston

    DOEpatents

    Meffert, Darrel Henry; Urven, Jr., Roger Leroy; Brown, Cory Andrew; Runge, Mark Harold

    2007-03-06

    A piston for an internal combustion engine is disclosed. The piston has a piston crown with a face having an interior annular edge. The piston also has first piston bowl recessed within the face of the piston crown. The first piston bowl has a bottom surface and an outer wall. A line extending from the interior annular edge of the face and tangent with the outer wall forms an interior angle greater than 90 degrees with the face of the piston. The piston also has a second piston bowl that is centrally located and has an upper edge located below a face of the piston crown.

  12. Maculopathy due to drug inhalation.

    PubMed

    Asensio-Sánchez, V M; Gonzalez-Buendia, L; Marcos-Fernández, M

    2014-08-01

    A case of maculopathy due to "poppers" is described. Poppers is a drug composed of various forms of alkyl nitrite. A 39 year-old man, who had been using poppers for years, was seen in the clinic with phosphenes, reduced visual acuity and central scotoma. The SD-OCT in the right eye showed disruption at the level of the IS/OS junction line. The SD-OCT scan in the left eye showed an outer rectangular retinal hole and an outer retinal cyst. Copyright © 2012 Sociedad Española de Oftalmología. Published by Elsevier Espana. All rights reserved.

  13. System and method for calibrating inter-star-tracker misalignments in a stellar inertial attitude determination system

    NASA Technical Reports Server (NTRS)

    Li, Rongsheng (Inventor); Wu, Yeong-Wei Andy (Inventor); Hein, Douglas H. (Inventor)

    2004-01-01

    A method and apparatus for determining star tracker misalignments is disclosed. The method comprises the steps of defining a defining a reference frame for the star tracker assembly according to a boresight of the primary star tracker and a boresight of a second star tracker wherein the boresight of the primary star tracker and a plane spanned by the boresight of the primary star tracker and the boresight of the second star tracker at least partially define a datum for the reference frame for the star tracker assembly; and determining the misalignment of the at least one star tracker as a rotation of the defined reference frame.

  14. Jet in jet in M87

    NASA Astrophysics Data System (ADS)

    Sob'yanin, Denis Nikolaevich

    2017-11-01

    New high-resolution Very Long Baseline Interferometer observations of the prominent jet in the M87 radio galaxy show a persistent triple-ridge structure of the transverse 15-GHz profile with a previously unobserved ultra-narrow central ridge. This radio structure can reflect the intrinsic structure of the jet, so that the jet as a whole consists of two embedded coaxial jets. A relativistic magnetohydrodynamic model is considered in which an inner jet is placed inside a hollow outer jet and the electromagnetic fields, pressures and other physical quantities are found. The entire jet is connected to the central engine that plays the role of a unipolar inductor generating voltage between the jets and providing opposite electric currents, and the charge neutrality and current closure together with the electromagnetic fields between the jets can contribute to the jet stabilization. The constant voltage is responsible for the similar widening laws observed for the inner and outer jets. This jet-in-jet structure can indicate simultaneous operation of two different jet-launching mechanisms, one relating to the central supermassive black hole and the other to the surrounding accretion disc. An inferred magnetic field of 80 G at the base is sufficient to provide the observed jet luminosity.

  15. Regulation of outer kinetochore Ndc80 complex-based microtubule attachments by the central kinetochore Mis12/MIND complex

    PubMed Central

    Kudalkar, Emily M.; Scarborough, Emily A.; Umbreit, Neil T.; Zelter, Alex; Gestaut, Daniel R.; Riffle, Michael; Johnson, Richard S.; MacCoss, Michael J.; Asbury, Charles L.; Davis, Trisha N.

    2015-01-01

    Multiple protein subcomplexes of the kinetochore cooperate as a cohesive molecular unit that forms load-bearing microtubule attachments that drive mitotic chromosome movements. There is intriguing evidence suggesting that central kinetochore components influence kinetochore–microtubule attachment, but the mechanism remains unclear. Here, we find that the conserved Mis12/MIND (Mtw1, Nsl1, Nnf1, Dsn1) and Ndc80 (Ndc80, Nuf2, Spc24, Spc25) complexes are connected by an extensive network of contacts, each essential for viability in cells, and collectively able to withstand substantial tensile load. Using a single-molecule approach, we demonstrate that an individual MIND complex enhances the microtubule-binding affinity of a single Ndc80 complex by fourfold. MIND itself does not bind microtubules. Instead, MIND binds Ndc80 complex far from the microtubule-binding domain and confers increased microtubule interaction of the complex. In addition, MIND activation is redundant with the effects of a mutation in Ndc80 that might alter its ability to adopt a folded conformation. Together, our results suggest a previously unidentified mechanism for regulating microtubule binding of an outer kinetochore component by a central kinetochore complex. PMID:26430240

  16. GEMINI-6 - EARTH-SKY - ETHIOPIA - OUTER SPACE

    NASA Image and Video Library

    1965-12-16

    S65-63162 (16 Dec. 1965) --- Central area of Ethiopia, south of Addis Ababa, showing Lakes Zwai, Langana, and Shala, as seen from the Gemini-6 spacecraft during its 14th revolution of Earth. Photo credit: NASA or National Aeronautics and Space Administration

  17. 75 FR 69122 - Outer Continental Shelf (OCS), Western and Central Planning Areas, Gulf of Mexico (GOM) Oil and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-10

    ..., Louisiana, Hilton New Orleans Airport, 901 Airline Drive Kenner, Louisiana 70062, 1 p.m. CST. Wednesday..., enclosed in an envelope labeled ``Comments on the Sales 218 and 222 SEIS'' to the Regional Supervisor...

  18. Trigonometric Parallaxes of Central Stars of Planetary Nebulae

    DTIC Science & Technology

    2007-02-01

    is a large nebula with a larger outer halo (Hewett et al. 2003; Rauch et al. 2004). Frew& Parker (2006) find that the nebula may be ionized ISM. 3...TRIGONOMETRIC PARALLAXES OF CENTRAL STARS OF PLANETARY NEBULAE Hugh C. Harris,1 Conard C. Dahn, Blaise Canzian, Harry H. Guetter, S. K. Leggett,2...parallaxes of 16 nearby planetary nebulae are presented, including reduced errors for seven objects with previous initial results and results for six new

  19. Gas insulated transmission line having tapered particle trapping ring

    DOEpatents

    Cookson, Alan H.

    1982-01-01

    A gas-insulated transmission line includes an outer sheath, an inner conductor, insulating supports and an insulating gas. A particle-trapping ring is secured to each insulating support, and it is comprised of a central portion and two tapered end portions. The ends of the particle trapping ring have a smaller diameter than the central portion of the ring, so as to enable the use of the particle trapping ring in a curved transmission line.

  20. EN FACE IMAGING OF PACHYCHOROID SPECTRUM DISORDERS WITH SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY.

    PubMed

    Dansingani, Kunal K; Balaratnasingam, Chandrakumar; Naysan, Jonathan; Freund, K Bailey

    2016-03-01

    To correlate clinical manifestations with choroidal morphology in pachychoroid disorders, including central serous chorioretinopathy, pachychoroid pigment epitheliopathy, pachychoroid neovasculopathy, and polypoidal choroidal vasculopathy, using en face swept-source optical coherence tomography (OCT). Patients with pachychoroid spectrum diagnoses were identified nonconsecutively through a review of charts and multimodal imaging. Each eye was categorized as uncomplicated pachychoroid, pachychoroid pigment epitheliopathy, central serous chorioretinopathy, pachychoroid neovasculopathy, or polypoidal choroidal vasculopathy. All patients included in this series then underwent bilateral swept-source OCT. Sixty-six eyes of 33 patients were included. Numbers assigned to diagnostic categories were 8 uncomplicated pachychoroid, 13 pachychoroid pigment epitheliopathy, 27 central serous chorioretinopathy, 15 pachychoroid neovasculopathy, and 3 polypoidal choroidal vasculopathy. One eye was classified as normal. Swept-source OCT choroidal thickness maps confirmed increased thickness under the areas of pachychoroid pigment epitheliopathy, central serous chorioretinopathy, type 1 NV (pachychoroid neovasculopathy), or polyps (polypoidal choroidal vasculopathy). En face swept-source OCT showed dilated outer choroidal vessels in all eyes. In several eyes with a chronic disease, focal choriocapillaris atrophy with inward displacement of deep choroidal vessels was noted. Although clinical manifestations of pachychoroid spectrum disorders vary considerably, these entities share morphologic findings in the choroid, including increased thickness and dilated outer choroidal vessels. En face swept-source OCT localizes these changes to disease foci and shows additional findings that may unify our understanding of disease pathogenesis.

  1. Fundus autofluorescence findings in central serous chorioretinopathy using two different confocal scanning laser ophthalmoscopes: correlation with functional and structural status.

    PubMed

    Shin, Joo Youn; Choi, Hun Jin; Lee, Jonghyun; Choi, Moonjung; Chung, Byunghoon; Byeon, Suk Ho

    2016-08-01

    To compare autofluorescence (AF) findings using wide-field (Optomap) and conventional (HRA-AF) confocal scanning laser ophthalmoscopy (cSLO) systems in patients with central serous chorioretinopathy (CSC), and to investigate the correlations between AF findings and functional and anatomical status. Optical coherence tomography (OCT) and AF images were compared in 73 eyes with serous retinal detachment (SRD) (group A) and 30 eyes without SRD (group B). We evaluated AF findings from the SRD region, atrophic area, and foveola. Correlations between AF findings and outer retinal abnormalities in OCT and visual acuity (VA) were analyzed. Optomap-AF was more effective than HRA-AF in identifying the margins of a detached area (P = 0.001) in group A, and for monitoring mild outer retinal damage (P = 0.041) in group B. The foveolar AF grades in both instruments were significantly correlated with VA and central foveal thickness (CFT) in both group A (Optomap, VA r s = 0.33, P = 0.012; CFT r s = -0.38, P = 0.002; HRA, VA r s = 0.62, P < 0.001; CFT r s = -0.70, P < 0.001) and group B (Optomap, VA r s = 0.71, P < 0.001, CFT r s = -0.78, P < 0.001; HRA, VA r s = 0.40, P = 0.026, CFT r s = -0.40, P = 0.030). Optomap-AF was found to be advantageous for monitoring subretinal status in eyes with SRD, and more accurately reflected mild outer retinal changes in eyes without SRD. Foveolar AF grades of both imaging modalities were significantly correlated with functional and anatomical status.

  2. Age, Sex, and Ethnic Variations in Inner and Outer Retinal and Choroidal Thickness on Spectral-Domain Optical Coherence Tomography.

    PubMed

    Bafiq, Rinoza; Mathew, Raeba; Pearce, Elizabeth; Abdel-Hey, Ahmed; Richardson, Matthew; Bailey, Thomas; Sivaprasad, Sobha

    2015-11-01

    To evaluate age, sex, and ethnic variations in inner and outer retinal and choroidal thickness and foveal pit, using spectral-domain optical coherence tomography (SD OCT). Single-center observational cross-sectional study. Ninety randomly selected, healthy individuals of white, black, and South Asian origin underwent SD OCT raster and enhanced depth imaging scan. Manual measurements of inner and outer retinal thickness and choroidal thickness up to 3 mm nasal and temporal to the fovea were performed. The age, sex, and ethnic differences in these parameters were analyzed. The mean inner retinal thickness was lower by approximately 12 μm in black subjects across the central retina compared to white subjects (P < .05). The central foveal thickness below the foveal pit was lower in eyes of blacks compared to South Asians (12 μm, P = .035) and white subjects (18 μm, P < .0001). The fovea was also significantly wider in eyes of black and South Asian subjects compared to white individuals. The inner retinal thickness decreased by 0.5 μm per year of age of subjects and was thinner by 6.1 μm (P < .02) in female compared to male subjects. The subfoveal choroidal thickness did not vary between ethnic groups but the temporal choroid was significantly thinner in black subjects (P < .05). The choroid showed an age-related decline in thickness of 2 μm per year of age of the subjects. Interethnic differences include wider fovea, lower central foveal thickness, and thinner inner retina in eyes of black subjects compared to their white and South Asian counterparts. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Characteristics of intraretinal deposits in acute central serous chorioretinopathy.

    PubMed

    Plateroti, Andrea M; Witmer, Matthew T; Kiss, Szilárd; D'Amico, Donald J

    2014-01-01

    To describe the temporal and spatial characteristics of intraretinal deposits in patients with acute central serous chorioretinopathy (CSC) using spectral domain optical coherence tomography (OCT). We retrospectively reviewed the medical records of all patients that presented with acute CSC to Weill Cornell Medical College from January 2012 to May 2013. Acute CSC was defined as a diagnosis of CSC within 4 months of the onset of symptoms. Only one eye per patient was included in the study. Each patient was imaged with spectral domain OCT at the initial office visit. The decision to reimage these patients was made by the treating physician. A total of 25 patients (25 eyes; 17 men and eight nonpregnant women) were included in this review. Seven of 25 patients (28%) demonstrated intraretinal deposits within the outer plexiform layer during the initial OCT, with deposits appearing as early as the same day as the onset of symptoms. A total of 25 of 25 patients (100%) demonstrated intraretinal deposits in the outer nuclear layer upon initial (76%) or follow-up OCT, as early as 2 days after the onset of symptoms. A total of 24 of 25 patients (96%) demonstrated deposits in the external limiting membrane upon a follow-up OCT, as early as 7 days from symptoms appearing. A total of 24 of 25 patients (96%) developed intraretinal deposits in the inner segment/outer segment layer upon follow-up OCT, appearing as early as 14 days after symptom onset. At the time of resolution of subretinal fluid, 20 of 25 patients (80%) demonstrated intraretinal deposits. Intraretinal deposits are present in the outer retinal layers in patients with acute CSC, with the deposits appearing progressively deeper within the retina as the condition evolves. Upon resolution of subretinal fluid, the deposits slowly resolve.

  4. Catalyst cartridge for carbon dioxide reduction unit

    NASA Technical Reports Server (NTRS)

    Holmes, R. F. (Inventor)

    1973-01-01

    A catalyst cartridge, for use in a carbon dioxide reducing apparatus in a life support system for space vehicles, is described. The catalyst cartridge includes an inner perforated metal wall, an outer perforated wall space outwardly from the inner wall, a base plate closing one end of the cartridge, and a cover plate closing the other end of the cartridge. The cover plate has a central aperture through which a supply line with a heater feeds a gaseous reaction mixture comprising hydrogen and carbon dioxide at a temperature from about 1000 to about 1400 F. The outer surfaces of the internal wall and the inner surfaces of the outer wall are lined with a ceramic fiber batting material of sufficient thickness to prevent carbon formed in the reaction from passing through it. The portion of the surfaces of the base and cover plates defined within the inner and outer walls are also lined with ceramic batting. The heated reaction mixture passes outwardly through the inner perforated wall and ceramic batting and over the catalyst. The solid carbon product formes is retained within the enclosure containing the catalyst. The solid carbon product formed is retained within the enclosure containing the catalyst. The water vapor and unreacted carbon dioxide and any intermediate products pass through the perforations of the outer wall.

  5. The Effects of Forming Parameters on Conical Ring Rolling Process

    PubMed Central

    Meng, Wen; Zhao, Guoqun; Guan, Yanjin

    2014-01-01

    The plastic penetration condition and biting-in condition of a radial conical ring rolling process with a closed die structure on the top and bottom of driven roll, simplified as RCRRCDS, were established. The reasonable value range of mandrel feed rate in rolling process was deduced. A coupled thermomechanical 3D FE model of RCRRCDS process was established. The changing laws of equivalent plastic strain (PEEQ) and temperature distributions with rolling time were investigated. The effects of ring's outer radius growth rate and rolls sizes on the uniformities of PEEQ and temperature distributions, average rolling force, and average rolling moment were studied. The results indicate that the PEEQ at the inner layer and outer layer of rolled ring are larger than that at the middle layer of ring; the temperatures at the “obtuse angle zone” of ring's cross-section are higher than those at “acute angle zone”; the temperature at the central part of ring is higher than that at the middle part of ring's outer surfaces. As the ring's outer radius growth rate increases at its reasonable value ranges, the uniformities of PEEQ and temperature distributions increase. Finally, the optimal values of the ring's outer radius growth rate and rolls sizes were obtained. PMID:25202716

  6. Investigation of growth features in several hydraulic fractures

    NASA Astrophysics Data System (ADS)

    Bykov, Alexander; Galybin, Alexander; Evdokimov, Alexander; Zavialova, Natalia; Zavialov, Ivan; Negodiaev, Sergey; Perepechkin, Ilia

    2017-04-01

    In this paper we simulate the growth of three or more interacting hydraulic fractures in the horizontal well with a cross flow of fluid between them. Calculation of the dynamics of cracks is performed in three dimensional space. The computation of the movement of fracturing fluid with proppant is performed in the two-dimensional space (the flow was averaged along crack aperture). For determining the hydraulic pipe resistance coefficient we used a generalization of the Reynolds number for fluids with power rheology and a generalization of the von Karman equation made by Dodge and Meiner. The calculations showed that the first crack was developing faster than the rest in homogeneous medium. During the steady loading the outer cracks pinch the inner cracks and it was shown that only the first and last fracture develop in extreme case. It is also possible to simulate the parameters at which the two developing outer cracks pinch the central one in the horizontal direction. In this case, the central crack may grow in the vertical direction.

  7. Leader psychobiography and social movement studies: a Kleinian case study of Bruce Gagnon and the outer space protection movement.

    PubMed

    Ormrod, James S

    2012-10-01

    This paper begins by highlighting the necessity of combining sociological and psychoanalytic approaches in the study of social movements, but acknowledges that psychobiographical studies of prominent movement leaders sit uneasily within the sociological tradition. The author attempts to illustrate that leader psychobiography can make a contribution to understanding social movements, however, provided it offers a way into understanding broader psychosocial issues within the movement. This is achieved through a psychobiographical portrait of Bruce Gagnon, a leader within the outer space protection movement. The author argues for the central importance of both paranoid-schizoid and depressive mechanisms throughout Gagnon's activist career. These eventually came to underpin Gagnon's commitment to protecting outer space as a Kleinian "good object." The paper concludes by suggesting how Gagnon's psychobiography might be instructive in attempts to understand the wider movement, utilizing Erikson's model for psychohistorical study as a framework.

  8. Multianode cylindrical proportional counter for high count rates

    DOEpatents

    Hanson, J.A.; Kopp, M.K.

    1980-05-23

    A cylindrical, multiple-anode proportional counter is provided for counting of low-energy photons (< 60 keV) at count rates of greater than 10/sup 5/ counts/sec. A gas-filled proportional counter cylinder forming an outer cathode is provided with a central coaxially disposed inner cathode and a plurality of anode wires disposed in a cylindrical array in coaxial alignment with and between the inner and outer cathodes to form a virtual cylindrical anode coaxial with the inner and outer cathodes. The virtual cylindrical anode configuration improves the electron drift velocity by providing a more uniform field strength throughout the counter gas volume, thus decreasing the electron collection time following the detection of an ionizing event. This avoids pulse pile-up and coincidence losses at these high count rates. Conventional RC position encoding detection circuitry may be employed to extract the spatial information from the counter anodes.

  9. Multianode cylindrical proportional counter for high count rates

    DOEpatents

    Hanson, James A.; Kopp, Manfred K.

    1981-01-01

    A cylindrical, multiple-anode proportional counter is provided for counting of low-energy photons (<60 keV) at count rates of greater than 10.sup.5 counts/sec. A gas-filled proportional counter cylinder forming an outer cathode is provided with a central coaxially disposed inner cathode and a plurality of anode wires disposed in a cylindrical array in coaxial alignment with and between the inner and outer cathodes to form a virtual cylindrical anode coaxial with the inner and outer cathodes. The virtual cylindrical anode configuration improves the electron drift velocity by providing a more uniform field strength throughout the counter gas volume, thus decreasing the electron collection time following the detection of an ionizing event. This avoids pulse pile-up and coincidence losses at these high count rates. Conventional RC position encoding detection circuitry may be employed to extract the spatial information from the counter anodes.

  10. Effect of horizontal pick and place locations on shoulder kinematics.

    PubMed

    Könemann, R; Bosch, T; Kingma, I; Van Dieën, J H; De Looze, M P

    2015-01-01

    In this study the effects of horizontal bin locations in an order picking workstation on upper arm elevation, trunk inclination and hand use were investigated. Eight subjects moved (self-paced) light or heavy products (0.2 and 3.0 kg) from a central product bin to an inner or outer order bin (at 60 or 150 cm) on the left or right side of the workstation, while movements were recorded. The outer compared to inner bin location resulted in more upper arm elevation and trunk inclination per work cycle, both in terms of number of peak values and in terms of time integrals of angles (which is a dose measure over time). Considering the peak values and time integrals per minute (instead of per work cycle), these effects are reduced, due to the higher cycle times for outer bins. Hand use (left, right or both) was not affected by order bin locations.

  11. Gravitational Instabilities in the Disks of Massive Protostars as an Explanation for Linear Distributions of Methanol Masers

    NASA Astrophysics Data System (ADS)

    Durisen, Richard H.; Mejia, Annie C.; Pickett, Brian K.; Hartquist, Thomas W.

    2001-12-01

    Evidence suggests that some masers associated with massive protostars may originate in the outer regions of large disks, at radii of hundreds to thousands of AU from the central mass. This is particularly true for methanol (CH3OH), for which linear distributions of masers are found with disklike kinematics. In three-dimensional hydrodynamics simulations we have made to study the effects of gravitational instabilities in the outer parts of disks around young low-mass stars, the nonlinear development of the instabilities leads to a complex of intersecting spiral shocks, clumps, and arclets within the disk and to significant time-dependent, nonaxisymmetric distortions of the disk surface. A rescaling of our disk simulations to the case of a massive protostar shows that conditions in the disturbed outer disk seem conducive to the appearance of masers if it is viewed edge-on.

  12. Three-dimensional spectral domain optical coherence tomography in X linked foveal retinoschisis

    PubMed Central

    Saxena, Sandeep; Manisha; Meyer, Carsten H

    2013-01-01

    Spectral domain optical coherence tomography (SD-OCT) was performed in two cases of bilateral X linked foveal retinoschisis of different age groups. On fundus examination spoke wheel and honeycomb pattern of cysts were observed along with retinal nerve fibre layer (RNFL) defects. On SD-OCT, schisis was observed in the outer plexiform layer. External limiting membrane disruption was observed in the subfoveal area, along with disruption of outer nuclear layer (ONL) and inner–outer segment junction. Elevation of ONL due to tractional pull of central palisade was a novel observation. Retinoschisis extended beyond the optic disc up to the nasal region. Extracted RNFL tomogram presented an unprecedented visualisation of schisis along 360° of the optic disc. Tractional elevation in the foveal area and schisis involving nasal region, not observed upon clinical examination, was highlighted on SD-OCT. This investigative modality is an important adjunct in the assessment of foveal retinoschisis. PMID:23563673

  13. A bill to designate the facility of the United States Postal Service located at 787 State Route 17M in Monroe, New York, as the "National Clandestine Service of the Central Intelligence Agency NCS Officer Gregg David Wenzel Memorial Post Office".

    THOMAS, 113th Congress

    Sen. Schumer, Charles E. [D-NY

    2014-07-24

    Senate - 07/24/2014 Read twice and referred to the Committee on Homeland Security and Governmental Affairs. (All Actions) Notes: For further action, see H.R.2112, which became Public Law 113-209 on 12/16/2014. Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  14. Lunar impact basins revealed by Gravity Recovery and Interior Laboratory measurements

    PubMed Central

    Neumann, Gregory A.; Zuber, Maria T.; Wieczorek, Mark A.; Head, James W.; Baker, David M. H.; Solomon, Sean C.; Smith, David E.; Lemoine, Frank G.; Mazarico, Erwan; Sabaka, Terence J.; Goossens, Sander J.; Melosh, H. Jay; Phillips, Roger J.; Asmar, Sami W.; Konopliv, Alexander S.; Williams, James G.; Sori, Michael M.; Soderblom, Jason M.; Miljković, Katarina; Andrews-Hanna, Jeffrey C.; Nimmo, Francis; Kiefer, Walter S.

    2015-01-01

    Observations from the Gravity Recovery and Interior Laboratory (GRAIL) mission indicate a marked change in the gravitational signature of lunar impact structures at the morphological transition, with increasing diameter, from complex craters to peak-ring basins. At crater diameters larger than ~200 km, a central positive Bouguer anomaly is seen within the innermost peak ring, and an annular negative Bouguer anomaly extends outward from this ring to the outer topographic rim crest. These observations demonstrate that basin-forming impacts remove crustal materials from within the peak ring and thicken the crust between the peak ring and the outer rim crest. A correlation between the diameter of the central Bouguer gravity high and the outer topographic ring diameter for well-preserved basins enables the identification and characterization of basins for which topographic signatures have been obscured by superposed cratering and volcanism. The GRAIL inventory of lunar basins improves upon earlier lists that differed in their totals by more than a factor of 2. The size-frequency distributions of basins on the nearside and farside hemispheres of the Moon differ substantially; the nearside hosts more basins larger than 350 km in diameter, whereas the farside has more smaller basins. Hemispherical differences in target properties, including temperature and porosity, are likely to have contributed to these different distributions. Better understanding of the factors that control basin size will help to constrain models of the original impactor population. PMID:26601317

  15. Lunar impact basins revealed by Gravity Recovery and Interior Laboratory measurements.

    PubMed

    Neumann, Gregory A; Zuber, Maria T; Wieczorek, Mark A; Head, James W; Baker, David M H; Solomon, Sean C; Smith, David E; Lemoine, Frank G; Mazarico, Erwan; Sabaka, Terence J; Goossens, Sander J; Melosh, H Jay; Phillips, Roger J; Asmar, Sami W; Konopliv, Alexander S; Williams, James G; Sori, Michael M; Soderblom, Jason M; Miljković, Katarina; Andrews-Hanna, Jeffrey C; Nimmo, Francis; Kiefer, Walter S

    2015-10-01

    Observations from the Gravity Recovery and Interior Laboratory (GRAIL) mission indicate a marked change in the gravitational signature of lunar impact structures at the morphological transition, with increasing diameter, from complex craters to peak-ring basins. At crater diameters larger than ~200 km, a central positive Bouguer anomaly is seen within the innermost peak ring, and an annular negative Bouguer anomaly extends outward from this ring to the outer topographic rim crest. These observations demonstrate that basin-forming impacts remove crustal materials from within the peak ring and thicken the crust between the peak ring and the outer rim crest. A correlation between the diameter of the central Bouguer gravity high and the outer topographic ring diameter for well-preserved basins enables the identification and characterization of basins for which topographic signatures have been obscured by superposed cratering and volcanism. The GRAIL inventory of lunar basins improves upon earlier lists that differed in their totals by more than a factor of 2. The size-frequency distributions of basins on the nearside and farside hemispheres of the Moon differ substantially; the nearside hosts more basins larger than 350 km in diameter, whereas the farside has more smaller basins. Hemispherical differences in target properties, including temperature and porosity, are likely to have contributed to these different distributions. Better understanding of the factors that control basin size will help to constrain models of the original impactor population.

  16. Seismic activity offshore Martinique and Dominica islands (Central Lesser Antilles subduction zone) from temporary onshore and offshore seismic networks

    NASA Astrophysics Data System (ADS)

    Ruiz, M.; Galve, A.; Monfret, T.; Sapin, M.; Charvis, P.; Laigle, M.; Evain, M.; Hirn, A.; Flueh, E.; Gallart, J.; Diaz, J.; Lebrun, J. F.

    2013-09-01

    This work focuses on the analysis of a unique set of seismological data recorded by two temporary networks of seismometers deployed onshore and offshore in the Central Lesser Antilles Island Arc from Martinique to Guadeloupe islands. During the whole recording period, extending from January to the end of August 2007, more than 1300 local seismic events were detected in this area. A subset of 769 earthquakes was located precisely by using HypoEllipse. We also computed focal mechanisms using P-wave polarities of the best azimuthally constrained earthquakes. We detected earthquakes beneath the Caribbean forearc and in the Atlantic oceanic plate as well. At depth seismicity delineates the Wadati-Benioff Zone down to 170 km depth. The main seismic activity is concentrated in the lower crust and in the mantle wedge, close to the island arc beneath an inner forearc domain in comparison to an outer forearc domain where little seismicity is observed. We propose that the difference of the seismicity beneath the inner and the outer forearc is related to a difference of crustal structure between the inner forearc interpreted as a dense, thick and rigid crustal block and the lighter and more flexible outer forearc. Seismicity is enhanced beneath the inner forearc because it likely increases the vertical stress applied to the subducting plate.

  17. Heat capacity of a self-gravitating spherical shell of radiations

    NASA Astrophysics Data System (ADS)

    Kim, Hyeong-Chan

    2017-10-01

    We study the heat capacity of a static system of self-gravitating radiations analytically in the context of general relativity. To avoid the complexity due to a conical singularity at the center, we excise the central part and replace it with a regular spherically symmetric distribution of matters of which specifications we are not interested in. We assume that the mass inside the inner boundary and the locations of the inner and the outer boundaries are given. Then, we derive a formula relating the variations of physical parameters at the outer boundary with those at the inner boundary. Because there is only one free variation at the inner boundary, the variations at the outer boundary are related, which determines the heat capacity. To get an analytic form for the heat capacity, we use the thermodynamic identity δ Srad=β δ Mrad additionally, which is derived from the variational relation of the entropy formula with the restriction that the mass inside the inner boundary does not change. Even if the radius of the inner boundary of the shell goes to zero, in the presence of a central conical singularity, the heat capacity does not go to the form of the regular sphere. An interesting discovery is that another legitimate temperature can be defined at the inner boundary which is different from the asymptotic one β-1.

  18. Structural basis for maintenance of bacterial outer membrane lipid asymmetry.

    PubMed

    Abellón-Ruiz, Javier; Kaptan, Shreyas S; Baslé, Arnaud; Claudi, Beatrice; Bumann, Dirk; Kleinekathöfer, Ulrich; van den Berg, Bert

    2017-12-01

    The Gram-negative bacterial outer membrane (OM) is a unique bilayer that forms an efficient permeation barrier to protect the cell from noxious compounds 1 , 2 . The defining characteristic of the OM is lipid asymmetry, with phospholipids comprising the inner leaflet and lipopolysaccharides comprising the outer leaflet 1-3 . This asymmetry is maintained by the Mla pathway, a six-component system that is widespread in Gram-negative bacteria and is thought to mediate retrograde transport of misplaced phospholipids from the outer leaflet of the OM to the cytoplasmic membrane 4 . The OM lipoprotein MlaA performs the first step in this process via an unknown mechanism that does not require external energy input. Here we show, using X-ray crystallography, molecular dynamics simulations and in vitro and in vivo functional assays, that MlaA is a monomeric α-helical OM protein that functions as a phospholipid translocation channel, forming a ~20-Å-thick doughnut embedded in the inner leaflet of the OM with a central, amphipathic pore. This architecture prevents access of inner leaflet phospholipids to the pore, but allows outer leaflet phospholipids to bind to a pronounced ridge surrounding the channel, followed by diffusion towards the periplasmic space. Enterobacterial MlaA proteins form stable complexes with OmpF/C 5,6 , but the porins do not appear to play an active role in phospholipid transport. MlaA represents a lipid transport protein that selectively removes outer leaflet phospholipids to help maintain the essential barrier function of the bacterial OM.

  19. Modeling synchronization in networks of delay-coupled fiber ring lasers.

    PubMed

    Lindley, Brandon S; Schwartz, Ira B

    2011-11-21

    We study the onset of synchronization in a network of N delay-coupled stochastic fiber ring lasers with respect to various parameters when the coupling power is weak. In particular, for groups of three or more ring lasers mutually coupled to a central hub laser, we demonstrate a robust tendency toward out-of-phase (achronal) synchronization between the N-1 outer lasers and the single inner laser. In contrast to the achronal synchronization, we find the outer lasers synchronize with zero-lag (isochronal) with respect to each other, thus forming a set of N-1 coherent fiber lasers. © 2011 Optical Society of America

  20. The Central Role of Tether-Cutting Reconnection in the Production of CMEs

    NASA Technical Reports Server (NTRS)

    Moore, Ron; Sterling, Alphonse; Suess, Steve

    2007-01-01

    This viewgraph presentation describes tether-cutting reconnection in the production of Coronal Mass Ejections (CMEs). The topics include: 1) Birth and Release of the CME Plasmoid; 2) Resulting CME in Outer Corona; 3) Governing Role of Surrounding Field; 4) Testable Prediction of the Standard Scenario Magnetic Bubble CME Model; 5) Lateral Pressure in Outer Corona; 6) Measured Angular Widths of 3 CMEs; 7) LASCO Image of each CME at Final Width; 8) Source of the CME of 2002 May 20; 9) Source of the CME of 1999 Feb 9; 10) Source of the CME of 2003 Nov 4; and 11) Test Results.

  1. The ATCA CABB Line Survey on Centaurus A: Properties of the Molecular Gas from the Dust Lanes to the Central Engine

    NASA Astrophysics Data System (ADS)

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

    2011-04-01

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

  2. SPARK GAP SWITCH

    DOEpatents

    Neal, R.B.

    1957-12-17

    An improved triggered spark gap switch is described, capable of precisely controllable firing time while switching very large amounts of power. The invention in general comprises three electrodes adjustably spaced and adapted to have a large potential impressed between the outer electrodes. The central electrode includes two separate elements electrically connected togetaer and spaced apart to define a pair of spark gaps between the end electrodes. Means are provided to cause the gas flow in the switch to pass towards the central electrode, through a passage in each separate element, and out an exit disposed between the two separate central electrode elements in order to withdraw ions from the spark gap.

  3. Starbursts triggered by central overpressure in interacting galaxies

    NASA Technical Reports Server (NTRS)

    Jog, Chanda J.; Das, Mousumi

    1993-01-01

    A triggering mechanism for the origin of enhanced, massive-star formation in the central regions of interacting spiral galaxy pairs is proposed. Our mechanism is based on the detailed evolution of a realistic interstellar medium in a galaxy following an encounter. As a disk giant molecular cloud (GMC) tumbles into the central region following a galaxy encounter, it undergoes a radiative shock compression via the pre-existing high pressure of the central intercloud medium. The shocked outer shell of a GMC becomes gravitationally unstable and begins to fragment thus resulting in a burst of star formation, when the growth time for the gravitational instabilities in the shell becomes smaller than the crossing time of the shock. The resulting values of typical infrared luminosity agree with observations.

  4. A distributed database view of network tracking systems

    NASA Astrophysics Data System (ADS)

    Yosinski, Jason; Paffenroth, Randy

    2008-04-01

    In distributed tracking systems, multiple non-collocated trackers cooperate to fuse local sensor data into a global track picture. Generating this global track picture at a central location is fairly straightforward, but the single point of failure and excessive bandwidth requirements introduced by centralized processing motivate the development of decentralized methods. In many decentralized tracking systems, trackers communicate with their peers via a lossy, bandwidth-limited network in which dropped, delayed, and out of order packets are typical. Oftentimes the decentralized tracking problem is viewed as a local tracking problem with a networking twist; we believe this view can underestimate the network complexities to be overcome. Indeed, a subsequent 'oversight' layer is often introduced to detect and handle track inconsistencies arising from a lack of robustness to network conditions. We instead pose the decentralized tracking problem as a distributed database problem, enabling us to draw inspiration from the vast extant literature on distributed databases. Using the two-phase commit algorithm, a well known technique for resolving transactions across a lossy network, we describe several ways in which one may build a distributed multiple hypothesis tracking system from the ground up to be robust to typical network intricacies. We pay particular attention to the dissimilar challenges presented by network track initiation vs. maintenance and suggest a hybrid system that balances speed and robustness by utilizing two-phase commit for only track initiation transactions. Finally, we present simulation results contrasting the performance of such a system with that of more traditional decentralized tracking implementations.

  5. The deflection of circular mirrors of linearly varying thickness supported along a central hole and free along the outer edge.

    PubMed

    Prevenslik, T V

    1968-10-01

    Most cassegrainian mirrors supported along the central hole are designed for deflection tolerances using the theory for solid, constant thickness plates. Where tolerances are critical, the mirror is usually made thicker, thereby reducing the deflection, but also increasing the weight of the mirror. Weight can be reduced by using a honeycomb design; however, manufacturing problems result because of the inherent complexity. To circumvent the disadvantages of excessive weight in the solid, constant thickness design and the complexity of the honeycomb design, a lightweight, yet simple design would be desirable. A possible lightweight, yet simple design would be a solid mirror of linearly varying thickness, decreasing in thickness from the center to the outer edge. As mirrors of linearly varying thickness may provide the best solution under combined deflection and weight restraints, a design basis is required and found in small deflection plate theory. The work of H. Conway was extended to account for pressure loading proportional to mirror density for the case when Poisson's ratio is ?. Closed form solutions for the slope of the linearly varying thickness mirrors were obtained for fixed and simply supported boundary conditions along the central hole. Maximum deflections were obtained by numerical integration and compared with the results for comparable constant thickness mirrors.

  6. Saturn Apollo Program

    NASA Image and Video Library

    1960-01-01

    The Saturn I S-I stage is being assembled in the fabrication and engineering laboratory at the Marshall Space Flight Center. The two end spider beams are cornected to the central 267-centimeter diameter liquid-oxygen (LOX) tank. The 178-centimeter outer tank, used alternately for liquid oxygen and kerosene, is being lifted into position.

  7. High-Temperature, Bellows Hybrid Seal

    NASA Technical Reports Server (NTRS)

    Steinetz, Bruce M. (Inventor); Sirocky, Paul J. (Inventor)

    1994-01-01

    A high-temperature hybrid seal is constructed of multiple elements to meet the many demands placed on the seal. The primary elements are: a central high-temperature bellows, a braided ceramic sheath covering the bellows, an outer abrasion resistant sheath covering the ceramic sheath, and a structurally-sound seal-end termination.

  8. 77 FR 2979 - Environmental Impacts Statements; Notice of Availability

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-20

    ... Stand Alone Gas Pipeline, Construction and Operation of a 737 mile Pipeline to Transport Supply of Natural Gas and Natural Gas Liquids from Alaska's North Slope to Fairbanks, Anchorage and the Cook Inlet..., Gulf of Mexico Outer Continental Shelf Oil and Gas Lease Sales: 2012 Central Planning Area Lease Sales...

  9. Chapter 6: CPV Tracking and Trackers

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

    Luque-Heredia, Ignacio; Magalhaes, Pedro; Muller, Matthew

    2016-04-15

    This chapter explains the functional requirements of a concentrator photovoltaic (CPV) sun tracker. It derives the design specifications of a CPV tracker. The chapter presents taxonomy of trackers describing the most common tracking architectures, based on the number of axes, their relative position, and the foundation and placing of tracking drives. It deals with the structural issues related to tracker design, mainly related to structural flexure and its impact on the system's acceptance angle. The chapter analyzes the auto-calibrated sun tracking control, by describing the state of the art and its development background. It explores the sun tracking accuracy measurementmore » with a practical example. The chapter discusses tracker manufacturing and tracker field works. It reviews survey of different types of tracker designs obtained from different manufacturers. Finally, the chapter deals with IEC62817, the technical standard developed for CPV sun trackers.« less

  10. Structural and functional changes associated with normal and abnormal fundus autofluorescence in patients with retinitis pigmentosa.

    PubMed

    Greenstein, Vivienne C; Duncker, Tobias; Holopigian, Karen; Carr, Ronald E; Greenberg, Jonathan P; Tsang, Stephen H; Hood, Donald C

    2012-02-01

    To analyze the structure and visual function of regions bordering the hyperautofluorescent ring/arcs in retinitis pigmentosa. Twenty-one retinitis pigmentosa patients (21 eyes) with rings/arcs and 21 normal individuals (21 eyes) were studied. Visual sensitivity in the central 10° was measured with microperimetry. Retinal structure was evaluated with spectral-domain optical coherence tomography. The distance from the fovea to disruption/loss of the inner outer segment (IS/OS) junction and thicknesses of the total receptor plus retinal pigment epithelial complex and outer segment plus retinal pigment epithelial complex layers were measured. Results were compared with measurements of the distance from the fovea to the inner and outer borders of the ring/arc seen on fundus autofluorescence. Disruption/loss of the inner outer segment junction occurred closer to the inner border of the ring/arc and it was closer to the fovea in eight eyes. For 19 eyes, outer segment plus and receptor plus RPE complex thicknesses were significantly decreased at locations closer to the fovea than the appearance of the inner border of hyperautofluorescence. Mean visual sensitivity was decreased inside, across, and outside the ring/arc by 3.5 ± 3.8, 8.9 ± 4.8, and 17.0 ± 2.4 dB, respectively. Structural and functional changes can occur inside the hyperfluorescent ring/arc in retinitis pigmentosa.

  11. Preparation of Geophysical Fluid Flow Experiments ( GeoFlow ) in the Fluid Science Laboratory on ISS

    NASA Astrophysics Data System (ADS)

    Egbers, C.

    The ,,GeoFlow" is an ESA experiment planned for the Fluid Science Laboratory on ISS under the scientific coordination (PI) of the Department of Aerodynamics and Fluidmechanics (LAS) at the Brandenburg Technical University (BTU) of Cottbus, Germany. The objective of the experiment is to study thermal convection in the gap between two concentric rotating (full) spheres. A central symmetric force field similar to the gravity field acting on planets can be produced by applying a high voltage between inner and outer sphere using the dielectrophoretic effect (rotating capacitor). To counter the unidirectional gravity under terrestrial conditions, this experiment requires a microgravity environment. The parameters of the experiment are chosen in analogy to the thermal convective motions in the outer core of the Earth. In analogy to geophysical motions in the Earth's liquid core the exp eriment can rotate as solid body as well as differential (inner to outer). Thermal convection is produced by heating the inner sphere and cooling the outer ones. Furtheron, the variation of radius ratio between inner and outer sphere is foreseen as a parameter variation. The flows to be investigated will strongly depend on the gap width and on the Prandtl number. Results of preparatory experiments and numerical simulation of the space experiment will be presented. Funding from DLR under grant 50 WM 0122 is greatfully ackwnoledged.

  12. DYF-1 Is Required for Assembly of the Axoneme in Tetrahymena thermophila▿ †

    PubMed Central

    Dave, Drashti; Wloga, Dorota; Sharma, Neeraj; Gaertig, Jacek

    2009-01-01

    In most cilia, the axoneme can be subdivided into three segments: proximal (the transition zone), middle (with outer doublet microtubules), and distal (with singlet extensions of outer doublet microtubules). How the functionally distinct segments of the axoneme are assembled and maintained is not well understood. DYF-1 is a highly conserved ciliary protein containing tetratricopeptide repeats. In Caenorhabditis elegans, DYF-1 is specifically needed for assembly of the distal segment (G. Ou, O. E. Blacque, J. J. Snow, M. R. Leroux, and J. M. Scholey. Nature. 436:583-587, 2005). We show that Tetrahymena cells lacking an ortholog of DYF-1, Dyf1p, can assemble only extremely short axoneme remnants that have structural defects of diverse natures, including the absence of central pair and outer doublet microtubules and incomplete or absent B tubules on the outer microtubules. Thus, in Tetrahymena, DYF-1 is needed for either assembly or stability of the entire axoneme. Our observations support the conserved function for DYF-1 in axoneme assembly or stability but also show that the consequences of loss of DYF-1 for axoneme segments are organism specific. PMID:19581442

  13. A kinematic determination of the structure of the double ring planetary nebula NGC 2392, the Eskimo

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

    O'dell, C.R.; Weiner, L.D.; Chu, Yoyhua

    Slit spectra and existing velocity cube data have been used to determine the structure of the double ring PN NGC 2392. The inner shell is a stellar wind-sculpted prolate spheroid with a ratio of axes of 2:1 and the approaching end of the long axis pointed 20 deg from the line of sight in P.A. = 200 deg. The outer ring is caused by an outer disk with density dropping off with distance from the central star and with distance from its plane, which is the same as the equatorial band of high density in the inner shell. The outermore » disk contains a ring of higher density knots at a distance of 16 arcsec and is losing material through free expansion, forming an outer envelope of increasing velocity. Forbidden S II spectra are used to determine the densities in all of the major regions of the nebula. It is argued that the filamentary cores at the centers of the knots seen in the outer ring originate in the sublimation of bodies formed at the same time as the parent star. 26 refs.« less

  14. PVOL: The Planetary Virtual Observatory & Laboratory. An online database of the Outer Planets images.

    NASA Astrophysics Data System (ADS)

    Morgado, A.; Sánchez-Lavega, A.; Rojas, J. F.; Hueso, R.

    2005-08-01

    The collaboration between amateurs astronomers and the professional community has been fruitful on many areas of astronomy. The development of the Internet has allowed a better than ever capability of sharing information worldwide and access to other observers data. For many years now the International Jupiter Watch (IJW) Atmospheric discipline has coordinated observational efforts for long-term studies of the atmosphere of Jupiter. The International Outer Planets Watch (IOPW) has extended its labours to the four Outer Planets. Here we present the Planetary Virtual Observatory & Laboratory (PVOL), a website database where we integer IJW and IOPW images. At PVOL observers can submit their data and professionals can search for images under a wide variety of useful criteria such as date and time, filters used, observer, or central meridian longitude. PVOL is aimed to grow as an organized easy to use database of amateur images of the Outer Planets. The PVOL web address is located at http://www.pvol.ehu.es/ and coexists with the traditional IOPW site: http://www.ehu.es/iopw/ Acknowledgements: This work has been funded by Spanish MCYT PNAYA2003-03216, fondos FEDER and Grupos UPV 15946/2004. R. Hueso acknowledges a post-doc fellowship from Gobierno Vasco.

  15. NIF Double Shell outer/inner shell collision experiments

    NASA Astrophysics Data System (ADS)

    Merritt, E. C.; Loomis, E. N.; Wilson, D. C.; Cardenas, T.; Montgomery, D. S.; Daughton, W. S.; Dodd, E. S.; Desjardins, T.; Renner, D. B.; Palaniyappan, S.; Batha, S. H.; Khan, S. F.; Smalyuk, V.; Ping, Y.; Amendt, P.; Schoff, M.; Hoppe, M.

    2017-10-01

    Double shell capsules are a potential low convergence path to substantial alpha-heating and ignition on NIF, since they are predicted to ignite and burn at relatively low temperatures via volume ignition. Current LANL NIF double shell designs consist of a low-Z ablator, low-density foam cushion, and high-Z inner shell with liquid DT fill. Central to the Double Shell concept is kinetic energy transfer from the outer to inner shell via collision. The collision determines maximum energy available for compression and implosion shape of the fuel. We present results of a NIF shape-transfer study: two experiments comparing shape and trajectory of the outer and inner shells at post-collision times. An outer-shell-only target shot measured the no-impact shell conditions, while an `imaging' double shell shot measured shell conditions with impact. The `imaging' target uses a low-Z inner shell and is designed to perform in similar collision physics space to a high-Z double shell but can be radiographed at 16keV, near the viable 2DConA BL energy limit. Work conducted under the auspices of the U.S. DOE by LANL under contract DE-AC52-06NA25396.

  16. Inner and outer star forming regions over the disks of spiral galaxies. I. Sample characterization

    NASA Astrophysics Data System (ADS)

    Rodríguez-Baras, M.; Díaz, A. I.; Rosales-Ortega, F. F.; Sánchez, S. F.

    2018-01-01

    Context. The knowledge of abundance distributions is central to understanding the formation and evolution of galaxies. Most of the relations employed for the derivation of gas abundances have so far been derived from observations of outer disk H ii regions, despite the known differences between inner and outer regions. Aims: Using integral field spectroscopy (IFS) observations we aim to perform a systematic study and comparison of two inner and outer H ii regions samples. The spatial resolution of the IFS, the number of objects and the homogeneity and coherence of the observations allow a complete characterization of the main observational properties and differences of the regions. Methods: We analyzed a sample of 725 inner H ii regions and a sample of 671 outer H ii regions, all of them detected and extracted from the observations of a sample of 263 nearby, isolated, spiral galaxies observed by the CALIFA survey. Results: We find that inner H ii regions show smaller equivalent widths, greater extinction and luminosities, along with greater values of [N ii] λ6583/Hα and [O ii] λ3727/[O iii] λ5007 emission-line ratios, indicating higher metallicities and lower ionization parameters. Inner regions have also redder colors and higher photometric and ionizing masses, although MionMphot is slighty higher for the outer regions. Conclusions: This work shows important observational differences between inner and outer H ii regions in star forming galaxies not previously studied in detail. These differences indicate that inner regions have more evolved stellar populations and are in a later evolution state with respect to outer regions, which goes in line with the inside-out galaxy formation paradigm. Table 4 is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/609/A102

  17. Science with the solar optical telescope

    NASA Technical Reports Server (NTRS)

    Jordan, S. D.; Hogan, G. D.

    1984-01-01

    The Solar Optical Telescope (SOT) is designed to provide the solar physics community with the data necessary for solving several fundamental problems in the energetics and dynamics of the solar atmosphere. Among these problems are questions on the origin and evolution of the sun's magnetic field, heating of the outer solar atmosphere, and sources of the solar wind in the lower lying regions of the outer atmosphere. The SOT will be built under the management of NASA's Goddard Space Flight Center, with science instruments provided by teams led by Principal Investigators. The telescope will be built by the Perkin-Elmer Corporation, and the science instruments selected for the first flight will be provided by the Lockheed Palo Alto Research Laboratory (LPARL) and the California Institute of Technology, with actual construction of a combined science instrument taking place at the LPARL. The SOT has a 1.3-meter-diameter primary mirror that will be capable of achieving diffraction-limited viewing in the visible of 0.1 arc-second. This dimension is less than a hydrodynamic scale-height or a mean-free-path of a continuum photon in the solar atmosphere. Image stability will be achieved by a control system in the telescope, which moves both the primary and tertiary mirrors in tandem, and will be further enhanced by a correlation tracker in the combined science instrument. The SOT Facility is currently scheduled for its first flight on Spacelab at the beginning of the 1990's.

  18. LysoTracker and MitoTracker Red are transport substrates of P-glycoprotein: implications for anticancer drug design evading multidrug resistance.

    PubMed

    Zhitomirsky, Benny; Farber, Hodaya; Assaraf, Yehuda G

    2018-04-01

    LysoTracker and MitoTracker Red are fluorescent probes widely used for viable cell staining of lysosomes and mitochondria, respectively. They are utilized to study organelle localization and their resident proteins, assess organelle functionality and quantification of organelle numbers. The ATP-driven efflux transporter P-glycoprotein (P-gp) is expressed in normal and malignant tissues and extrudes structurally distinct endogenous and exogenous cytotoxic compounds. Thus, once aromatic hydrophobic compounds such as the above-mentioned fluorescent probes are recognized as transport substrates, efflux pumps including P-gp may abolish their ability to reach their cellular target organelles. Herein, we show that LysoTracker and MitoTracker Red are expelled from P-gp-overexpressing cancer cells, thus hindering their ability to fluorescently mark target organelles. We further demonstrate that tariquidar, a potent P-gp transport inhibitor, restores LysoTracker and MitoTracker Red cell entry. We conclude that LysoTracker and MitoTracker Red are P-gp transport substrates, and therefore, P-gp expression must be taken into consideration prior to cellular applications using these probes. Importantly, as MitoTracker was a superior P-gp substrate than LysoTracker Red, we discuss the implications for the future design of chemotherapeutics evading cancer multidrug resistance. Furthermore, restoration of MitoTracker Red fluorescence in P-gp-overexpressing cells may facilitate the identification of potent P-gp transport inhibitors (i.e. chemosensitizers). © 2018 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  19. A Radial Age Gradient in the Geometrically Thick Disk of the Milky Way

    NASA Astrophysics Data System (ADS)

    Martig, Marie; Minchev, Ivan; Ness, Melissa; Fouesneau, Morgan; Rix, Hans-Walter

    2016-11-01

    In the Milky Way, the thick disk can be defined using individual stellar abundances, kinematics, or age, or geometrically, as stars high above the midplane. In nearby galaxies, where only a geometric definition can be used, thick disks appear to have large radial scale lengths, and their red colors suggest that they are uniformly old. The Milky Way’s geometrically thick disk is also radially extended, but it is far from chemically uniform: α-enhanced stars are confined within the inner Galaxy. In simulated galaxies, where old stars are centrally concentrated, geometrically thick disks are radially extended, too. Younger stellar populations flare in the simulated disks’ outer regions, bringing those stars high above the midplane. The resulting geometrically thick disks therefore show a radial age gradient, from old in their central regions to younger in their outskirts. Based on our age estimates for a large sample of giant stars in the APOGEE survey, we can now test this scenario for the Milky Way. We find that the geometrically defined thick disk in the Milky Way has indeed a strong radial age gradient: the median age for red clump stars goes from ∼9 Gyr in the inner disk to 5 Gyr in the outer disk. We propose that at least some nearby galaxies could also have thick disks that are not uniformly old, and that geometrically thick disks might be complex structures resulting from different formation mechanisms in their inner and outer parts.

  20. Linear models for sound from supersonic reacting mixing layers

    NASA Astrophysics Data System (ADS)

    Chary, P. Shivakanth; Samanta, Arnab

    2016-12-01

    We perform a linearized reduced-order modeling of the aeroacoustic sound sources in supersonic reacting mixing layers to explore their sensitivities to some of the flow parameters in radiating sound. Specifically, we investigate the role of outer modes as the effective flow compressibility is raised, when some of these are expected to dominate over the traditional Kelvin-Helmholtz (K-H) -type central mode. Although the outer modes are known to be of lesser importance in the near-field mixing, how these radiate to the far-field is uncertain, on which we focus. On keeping the flow compressibility fixed, the outer modes are realized via biasing the respective mean densities of the fast (oxidizer) or slow (fuel) side. Here the mean flows are laminar solutions of two-dimensional compressible boundary layers with an imposed composite (turbulent) spreading rate, which we show to significantly alter the growth of instability waves by saturating them earlier, similar to in nonlinear calculations, achieved here via solving the linear parabolized stability equations. As the flow parameters are varied, instability of the slow modes is shown to be more sensitive to heat release, potentially exceeding equivalent central modes, as these modes yield relatively compact sound sources with lesser spreading of the mixing layer, when compared to the corresponding fast modes. In contrast, the radiated sound seems to be relatively unaffected when the mixture equivalence ratio is varied, except for a lean mixture which is shown to yield a pronounced effect on the slow mode radiation by reducing its modal growth.

  1. P-MaNGA: GRADIENTS IN RECENT STAR FORMATION HISTORIES AS DIAGNOSTICS FOR GALAXY GROWTH AND DEATH

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

    Li, Cheng; Wang, Enci; Lin, Lin

    2015-05-10

    We present an analysis of the data produced by the MaNGA prototype run (P-MaNGA), aiming to test how the radial gradients in recent star formation histories, as indicated by the 4000 Å break (D{sub n}(4000)), Hδ absorption (EW(Hδ{sub A})), and Hα emission (EW(Hα)) indices, can be useful for understanding disk growth and star formation cessation in local galaxies. We classify 12 galaxies observed on two P-MaNGA plates as either centrally quiescent (CQ) or centrally star-forming (CSF), according to whether D{sub n}(4000) measured in the central spaxel of each datacube exceeds 1.6. For each spaxel we generate both 2D maps and radialmore » profiles of D{sub n}(4000), EW(Hδ{sub A}), and EW(Hα). We find that CSF galaxies generally show very weak or no radial variation in these diagnostics. In contrast, CQ galaxies present significant radial gradients, in the sense that D{sub n}(4000) decreases, while both EW(Hδ{sub A}) and EW(Hα) increase from the galactic center outward. The outer regions of the galaxies show greater scatter on diagrams relating the three parameters than their central parts. In particular, the clear separation between centrally measured quiescent and star-forming galaxies in these diagnostic planes is largely filled in by the outer parts of galaxies whose global colors place them in the green valley, supporting the idea that the green valley represents a transition between blue-cloud and red-sequence phases, at least in our small sample. These results are consistent with a picture in which the cessation of star formation propagates from the center of a galaxy outward as it moves to the red sequence.« less

  2. Tumour location within the breast: Does tumour site have prognostic ability?

    PubMed

    Rummel, Seth; Hueman, Matthew T; Costantino, Nick; Shriver, Craig D; Ellsworth, Rachel E

    2015-01-01

    Tumour location within the breast varies with the highest frequency in the upper outer quadrant (UOQ) and lowest frequency in the lower inner quadrant (LIQ). Whether tumour location is prognostic is unclear. To determine whether tumour location is prognostic, associations between tumour site and clinicopathological characteristics were evaluated. All patients enrolled in the Clinical Breast Care Project whose tumour site-UOQ, upper inner quadrant (UIQ), central, LIQ, lower outer quadrant (LOQ)-was determined by a single, dedicated breast pathologist were included in this study. Patients with multicentric disease (n = 122) or tumours spanning multiple quadrants (n = 381) were excluded from further analysis. Clinicopathological characteristics were analysed using chi-square tests for univariate analysis with multivariate analysis performed using principal components analysis (PCA) and multiple logistic regression. Significance was defined as P < 0.05. Of the 980 patients with defined tumour location, 30 had bilateral disease. Tumour location in the UOQ (51.5%) was significantly higher than in the UIQ (15.6%), LOQ (14.2%), central (10.6%), or LIQ (8.1%). Tumours in the central quadrant were significantly more likely to have higher tumour stage (P = 0.003) and size (P < 0.001), metastatic lymph nodes (P < 0.001), and mortality (P = 0.011). After multivariate analysis, only tumour size and lymph node status remained significantly associated with survival. Evaluation of tumour location as a prognostic factor revealed that although tumours in the central region are associated with less favourable outcome, these associations are not independent of location but rather driven by larger tumour size. Tumours in the central region are more difficult to detect mammographically, resulting in larger tumour size at diagnosis and thus less favourable prognosis. Together, these data demonstrate that tumour location is not an independent prognostic factor.

  3. Amend the title so as to read: `Condemning Joseph Kony and the Lord's Resistance Army for committing crimes against humanity and mass atrocities, and supporting ongoing efforts by the United States Government and governments and regional organizations in central Africa to remove Joseph Kony and Lord's Resistance Army commanders from the battlefield.'.

    THOMAS, 112th Congress

    Sen. Coons, Christopher A. [D-DE

    2012-03-21

    Senate - 08/02/2012 Resolution agreed to in Senate with an amendment and an amendment to the Title and an amended preamble by Unanimous Consent. (All Actions) Tracker: This bill has the status Agreed to in SenateHere are the steps for Status of Legislation:

  4. To prohibit the Central Intelligence Agency from using an unmanned aerial vehicle to carry out a weapons strike or other deliberately lethal action and to transfer the authority to conduct such strikes or lethal action to the Department of Defense.

    THOMAS, 113th Congress

    Rep. Burgess, Michael C. [R-TX-26

    2014-02-11

    House - 02/11/2014 Referred to the Committee on Intelligence (Permanent Select), and in addition to the Committee on Armed Services, for a period to be subsequently determined by the Speaker, in each case for consideration of such provisions as fall within the jurisdiction of the... (All Actions) Tracker: This bill has the status IntroducedHere are the steps for Status of Legislation:

  5. A resolution calling for continued support for and an increased effort by the Governments of Pakistan, Afghanistan, and other Central Asian countries to effectively monitor and regulate the manufacture, sale, transport, and use of ammonium nitrate fertilizer in order to prevent the transport of ammonium nitrate into Afghanistan where the ammonium nitrate is used in improvised explosive devices.

    THOMAS, 111th Congress

    Sen. Casey, Robert P., Jr. [D-PA

    2010-06-28

    Senate - 06/28/2010 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (All Actions) Tracker: This bill has the status Agreed to in SenateHere are the steps for Status of Legislation:

  6. Generic framework for vessel detection and tracking based on distributed marine radar image data

    NASA Astrophysics Data System (ADS)

    Siegert, Gregor; Hoth, Julian; Banyś, Paweł; Heymann, Frank

    2018-04-01

    Situation awareness is understood as a key requirement for safe and secure shipping at sea. The primary sensor for maritime situation assessment is still the radar, with the AIS being introduced as supplemental service only. In this article, we present a framework to assess the current situation picture based on marine radar image processing. Essentially, the framework comprises a centralized IMM-JPDA multi-target tracker in combination with a fully automated scheme for track management, i.e., target acquisition and track depletion. This tracker is conditioned on measurements extracted from radar images. To gain a more robust and complete situation picture, we are exploiting the aspect angle diversity of multiple marine radars, by fusing them a priori to the tracking process. Due to the generic structure of the proposed framework, different techniques for radar image processing can be implemented and compared, namely the BLOB detector and SExtractor. The overall framework performance in terms of multi-target state estimation will be compared for both methods based on a dedicated measurement campaign in the Baltic Sea with multiple static and mobile targets given.

  7. Neurobiological Basis of Individual Variation in Stimulus-Reward Learning.

    PubMed

    Flagel, Shelly B; Robinson, Terry E

    2017-02-01

    Cues in the environment can guide behavior in adaptive ways, leading one towards valuable resources such as food, water, or a potential mate. However, cues in the environment may also serve as powerful motivators that lead to maladaptive patterns of behavior, such as addiction. Importantly, and central to this article, there is considerable individual variation in the extent to which reward cues gain motivational control over behavior. Here we describe an animal model that captures this individual variation, allowing us to better understand the psychological and neurobiological processes that contribute to cue-evoked behaviors. When a discrete cue is paired with a food reward in a Pavlovian manner it acquires greater control over motivated behavior in some rats ("sign-trackers, STs) than in others ("goal-trackers", GTs). We review studies that have exploited this animal model to parse the neurobiological mechanisms involved in learning associations between stimuli vs. those involved in attributing incentive salience to those same stimuli. The latter seems to be dependent on dopamine and subcortical circuits, whereas the former may engage more cortical "top-down" mechanisms.

  8. Refractive index sensing with Fano resonances in silicon oligomers

    PubMed Central

    Chong, Katie E.; Orton, Henry W.; Decker, Manuel; Miroshnichenko, Andrey E.; Brener, Igal; Kivshar, Yuri S.

    2017-01-01

    We demonstrate experimentally refractive index sensing with localized Fano resonances in silicon oligomers, consisting of six disks surrounding a central one of slightly different diameter. Owing to the low absorption and narrow Fano-resonant spectral features appearing as a result of the interference of the modes of the outer and the central disks, we demonstrate refractive index sensitivity of more than 150 nm RIU−1 with a figure of merit of 3.8. This article is part of the themed issue ‘New horizons for nanophotonics’. PMID:28220001

  9. Can a Free Wearable Activity Tracker Change Behavior? The Impact of Trackers on Adults in a Physician-Led Wellness Group.

    PubMed

    Gualtieri, Lisa; Rosenbluth, Sandra; Phillips, Jeffrey

    2016-11-30

    Wearable activity trackers (trackers) are increasingly popular devices used to track step count and other health indicators. Trackers have the potential to benefit those in need of increased physical activity, such as adults who are older and face significant health challenges. These populations are least likely to purchase trackers and most likely to face challenges in using them, yet may derive educational, motivational, and health benefits from their use once these barriers are removed. The aim of this pilot research is to investigate the use of trackers by adults with chronic medical conditions who have never used trackers previously. Specifically, we aim to determine (1) if participants would accept and use trackers to increase their physical activity; (2) if there were barriers to use besides cost and training; (3) if trackers would educate participants on their baseline and ongoing activity levels and support behavior change; and (4) if clinical outcomes would show improvements in participants' health. This study was conducted with patients (N=10) in a 12-week physician-led wellness group offered by Family Doctors, LLC. Patients were given trackers in the second week of The Wellness Group and were interviewed 2 to 4 weeks after it ended. The study investigators analyzed the interview notes to extract themes about the participants' attitudes and behavior changes and collected and analyzed participants' clinical data, including weight and low-density lipoprotein (LDL) cholesterol over the course of the study. Over the 12 to 14 weeks of tracker use, improvements were seen in clinical outcomes, attitudes towards the trackers, and physical activity behaviors. Participants lost an average of 0.5 lbs per week (SD 0.4), with a mean total weight loss of 5.97 lbs (P=.004). Other short-term clinical outcomes included a 9.2% decrease in LDL levels (P=.038). All participants reported an increase in well-being and confidence in their ability to lead more active lives. We identified the following 6 major attitudinal themes from our qualitative analysis of the interview notes: (1) barriers to tracker purchase included cost, perceived value, and choice confusion; (2) attitudes towards the trackers shifted for many, from half of the participants expressing excitement and hope and half expressing hesitation or trepidation, to all participants feeling positive towards their tracker at the time of the interviews; (3) trackers served as educational tools for baseline activity levels; (4) trackers provided concrete feedback on physical activity, which motivated behavior change; (5) tracker use reinforced wellness group activities and goals; and (6) although commitment to tracker use did not waver, external circumstances influenced some participants' ongoing use. Our findings suggest that adding trackers to wellness groups comprising primarily older adults with chronic medical conditions can support education and behavior change to be more physically active. The trackers increased participant self-efficacy by providing a tangible, visible reminder of a commitment to increasing activity and immediate feedback on step count and progress towards a daily step goal. While acceptance was high and attitudes ultimately positive, training and support are needed and short-term drop-off in participant use is to be expected. Future research will further consider the potential of trackers in older adults with chronic medical conditions who are unlikely to purchase them, and studies will use larger samples, continue over a longer period of time, and evaluate outcomes independent of a wellness group. ©Lisa Gualtieri, Sandra Rosenbluth, Jeffrey Phillips. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 30.11.2016.

  10. The protoplanetary system HD 100546 in Hα polarized light from SPHERE/ZIMPOL. A bar-like structure across the disk gap?

    NASA Astrophysics Data System (ADS)

    Mendigutía, I.; Oudmaijer, R. D.; Garufi, A.; Lumsden, S. L.; Huélamo, N.; Cheetham, A.; de Wit, W. J.; Norris, B.; Olguin, F. A.; Tuthill, P.

    2017-12-01

    Context. HD 100546 is one of the few known pre-main-sequence stars that may host a planetary system in its disk. Aims: This work aims to contribute to our understanding of HD 100546 by analyzing new polarimetric images with high spatial resolution. Methods: Using VLT/SPHERE/ZIMPOL with two filters in Hα and the adjacent continuum, we have probed the disk gap and the surface layers of the outer disk, covering a region <500 mas (<55 au at 109 pc) from the central star, at an angular resolution of 20 mas. Results: Our data show an asymmetry: the SE and NW regions of the outer disk are more polarized than the SW and NE regions. This asymmetry can be explained from a preferential scattering angle close to 90° and is consistent with previous polarization images. The outer disk in our observations extends from 13 ± 2 to 45 ± 9 au, with a position angle and inclination of 137 ± 5° and 44 ± 8°, respectively. The comparison with previous estimates suggests that the disk inclination could increase with the stellocentric distance, although the different measurements are still consistent within the error bars. In addition, no direct signature of the innermost candidate companion is detected from the polarimetric data, confirming recent results that were based on intensity imagery. We set an upper limit to its mass accretion rate <10-8 M⊙ yr-1 for a substellar mass of 15 MJup. Finally, we report the first detection (>3σ) of a 20 au bar-like structure that crosses the gap through the central region of HD 100546. Conclusions: In the absence of additional data, it is tentatively suggested that the bar could be dust dragged by infalling gas that radially flows from the outer disk to the inner region. This could represent an exceptional case in which a small-scale radial inflow is observed in a single system. If this scenario is confirmed, it could explain the presence of atomic gas in the inner disk that would otherwise accrete on to the central star on a timescale of a few months/years, as previously indicated from spectro-interferometric data, and could be related with additional (undetected) planets.

  11. Smoothed particle hydrodynamics simulations of black hole accretion: a step to model black hole feedback in galaxies

    NASA Astrophysics Data System (ADS)

    Barai, Paramita; Proga, Daniel; Nagamine, Kentaro

    2011-11-01

    We test how accurately the smoothed particle hydrodynamics (SPH) numerical technique can follow spherically symmetric Bondi accretion. Using the 3D SPH code GADGET-3, we perform simulations of gas accretion on to a central supermassive black hole of mass 108 M⊙ within the radial range of 0.1-200 pc. We carry out simulations without and with radiative heating by a central X-ray corona and radiative cooling. For an adiabatic case, the radial profiles of hydrodynamical properties match the Bondi solution, except near the inner and outer radius of the computational domain. The deviation from the Bondi solution close to the inner radius is caused by the combination of numerical resolution, artificial viscosity and our inner boundary condition. Near the outer radius (≤200 pc), we observe either an outflow or development of a non-spherical inflow unless the outer boundary conditions are very stringently implemented. Despite these issues related to the boundary conditions, we find that adiabatic Bondi accretion can be reproduced for durations of a few dynamical times at the Bondi radius, and for longer times if the outer radius is increased. In particular, the mass inflow rate at the inner boundary, which we measure, is within 3-4 per cent of the Bondi accretion rate. With radiative heating and cooling included, the spherically accreting gas takes a longer time to reach a steady state than the adiabatic Bondi accretion runs, and in some cases does not reach a steady state even within several hundred dynamical times. We find that artificial viscosity causes excessive heating near the inner radius, making the thermal properties of the gas inconsistent with a physical solution. This overheating occurs typically only in the supersonic part of the flow, so that it does not affect the mass accretion rate. We see that increasing the X-ray luminosity produces a lower central mass inflow rate, implying that feedback due to radiative heating is operational in our simulations. With a sufficiently high X-ray luminosity, the inflowing gas is radiatively heated up, and an outflow develops. We conclude that the SPH simulations can capture the gas dynamics needed to study radiative feedback, provided artificial viscosity alters only highly supersonic part of the inflow.

  12. Neutronic reactor

    DOEpatents

    Wende, Charles W. J.

    1976-08-17

    A safety rod for a nuclear reactor has an inner end portion having a gamma absorption coefficient and neutron capture cross section approximately equal to those of the adjacent shield, a central portion containing materials of high neutron capture cross section and an outer end portion having a gamma absorption coefficient at least equal to that of the adjacent shield.

  13. 77 FR 29683 - Outer Continental Shelf (OCS) Consolidated Central Gulf of Mexico Planning Area Sale; 216/222

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-18

    ... than 400 meters of water depth completed to a drilling depth of 20,000 feet TVD SS or deeper may... are specified as (1) less than 400 meters and (2) 400 meters or more. Successful Bidders: BOEM... summarized in the following table: [[Page 29686

  14. New species of mites from pine (Acarina: Tarsochelidae, Eupalopsellidae, Caligonellidae, Cryptognathidae, Raphignathidae, and Neophyllobiidae)

    Treesearch

    Robert L. Smiley; John C. Moser

    1968-01-01

    The purpose of this paper is to describe several new species of mites, most of which were found in the outer bark of Pinus taeda L. at Elizabeth, in central Louisiana. They were discovered in the course of research on the seasonal ecology of Dendroctonus frontalis Zimmerman

  15. 78 FR 42544 - Outer Continental Shelf (OCS), Gulf of Mexico (GOM), Oil and Gas Lease Sale, Western Planning...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-16

    ... Prepare a Supplemental Environmental Impact Statement (EIS) SUMMARY: Consistent with the regulations... 248; Central Planning Area (CPA) Lease Sales 227, 231, 235, 241, and 247, Final Environmental Impact... Supplemental Environmental Impact Statement (OCS EIS/EA BOEM 2013-0118) (WPA 233/CPA 231 Supplemental EIS). The...

  16. The Future of World Englishes in Language Testing

    ERIC Educational Resources Information Center

    Brown, James Dean

    2014-01-01

    This article begins by defining "world Englishes" (WEs) and the related paradigm of inner-, outer-, and expanding-circle English(es). The discussion then turns to the central concerns of the WEs and language testing (LT) communities with regard to how English tests can best be constructed to include various WEs by discussing (a) what…

  17. Saturn Apollo Program

    NASA Image and Video Library

    1960-01-01

    The Saturn I S-I stage is being assembled in the fabrication and engineering laboratory at the Marshall Space Flight Center. The two end spider beams are cornected to the central 267-centimeter diameter liquid-oxygen (LOX) tank. The first of the eight 178-centimeter outer tanks, used alternately for liquid oxygen and kerosene, is being lifted into position.

  18. Radiative shocks produced from spherical cryogenic implosions at the National Ignition Facility

    DOE PAGES

    Pak, A.; Divol, L.; Gregori, G.; ...

    2013-05-20

    Spherically expanding radiative shock waves have been observed from inertially confined implosion experiments at the National Ignition Facility. In these experiments, a spherical fusion target, initially 2 mm in diameter, is compressed via the pressure induced from the ablation of the outer target surface. At the peak compression of the capsule, x-ray and nuclear diagnostics indicate the formation of a central core, with a radius and ion temperature of ~20 μm and ~ 2 keV, respectively. This central core is surrounded by a cooler compressed shell of deuterium-tritium fuel that has an outer radius of ~40 μm and a densitymore » of >500 g/cm 3. Using inputs from multiple diagnostics, the peak pressure of the compressed core has been inferred to be of order 100 Gbar for the implosions discussed here. Furthermore, the shock front, initially located at the interface between the high pressure compressed fuel shell and surrounding in-falling low pressure ablator plasma, begins to propagate outwards after peak compression has been reached.« less

  19. Seismic expression of the Chesapeake Bay impact crater: Structural and morphologic refinements based on new seismic data

    USGS Publications Warehouse

    Poag, C. Wylie; Hutchinson, Deborah R.; Colman, Steve M.; Lee, Myung W.; Dressler, B.O.; Sharpton, V.L.

    1999-01-01

    This work refines previous interpretations of the structure and morphology of the Chesapeake Bay impact crater on the basis of more than 1,200 km of multichannel and single-channel seismic reflection profiles collected in the bay and on the adjacent continental shelf. The outer rim, formed in sedimentary rocks, is irregularly circular, with an average diameter of ~85 km. A 20–25-km-wide annular trough separates the outer rim from an ovate, crystalline peak ring of ~200 m of maximum relief. The inner basin is 35–40 km in diameter, and at least 1.26 km deep. A crystalline(?) central peak, approximately 1 km high, is faintly imaged on three profiles, and also is indicated by a small positive Bouguer gravity anomaly. These features classify the crater as a complex peak-ring/central peak crater. Chesapeake Bay Crater is most comparable to the Ries and Popigai Craters on Earth; to protobasins on Mars, Mercury, and the Moon; and to type D craters on Venus.

  20. Nonlinear Stability and Structure of Compressible Reacting Mixing Layers

    NASA Technical Reports Server (NTRS)

    Day, M. J.; Mansour, N. N.; Reynolds, W. C.

    2000-01-01

    The parabolized stability equations (PSE) are used to investigate issues of nonlinear flow development and mixing in compressible reacting shear layers. Particular interest is placed on investigating the change in flow structure that occurs when compressibility and heat release are added to the flow. These conditions allow the 'outer' instability modes- one associated with each of the fast and slow streams-to dominate over the 'central', Kelvin-Helmholtz mode that unaccompanied in incompressible nonreacting mixing layers. Analysis of scalar probability density functions in flows with dominant outer modes demonstrates the ineffective, one-sided nature of mixing that accompany these flow structures. Colayer conditions, where two modes have equal growth rate and the mixing layer is formed by two sets of vortices, offer some opportunity for mixing enhancement. Their extent, however, is found to be limited in the mixing layer's parameter space. Extensive validation of the PSE technique also provides a unique perspective on central- mode vortex pairing, further supporting the view that pairing is primarily governed perspective sheds insight on how linear stability theory is able to provide such an accurate prediction of experimentally-observed, fully nonlinear flow phenomenon.

  1. Architectures of Lipid Transport Systems for the Bacterial Outer Membrane.

    PubMed

    Ekiert, Damian C; Bhabha, Gira; Isom, Georgia L; Greenan, Garrett; Ovchinnikov, Sergey; Henderson, Ian R; Cox, Jeffery S; Vale, Ronald D

    2017-04-06

    How phospholipids are trafficked between the bacterial inner and outer membranes through the hydrophilic space of the periplasm is not known. We report that members of the mammalian cell entry (MCE) protein family form hexameric assemblies with a central channel capable of mediating lipid transport. The E. coli MCE protein, MlaD, forms a ring associated with an ABC transporter complex in the inner membrane. A soluble lipid-binding protein, MlaC, ferries lipids between MlaD and an outer membrane protein complex. In contrast, EM structures of two other E. coli MCE proteins show that YebT forms an elongated tube consisting of seven stacked MCE rings, and PqiB adopts a syringe-like architecture. Both YebT and PqiB create channels of sufficient length to span the periplasmic space. This work reveals diverse architectures of highly conserved protein-based channels implicated in the transport of lipids between the membranes of bacteria and some eukaryotic organelles. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Hydrocode Simulations of the Chesapeake Bay Impact

    NASA Technical Reports Server (NTRS)

    Collins, G. S.; Melosh, H. J.

    2004-01-01

    The Chesapeake Bay Impact Crater (CBIC) formed about 35 million years ago (late Eocene), in a shallow marine environment (400-600 m water depth). The crater is complex and developed in a multi-layer, rheologically-variable target that comprised 400-1000 meters of soft, water-saturated sediments overlying crystalline basement. Seismic reflection data illustrates that the Chesapeake Bay crater morphology - often described as an "inverted sombrero" - is similar to other marine-target impact craters. It consists of a approx. 1 - 1.5-km deep, highly disturbed central crater, surrounded by a shallower, less deformed basin. The inner crater has a diameter of approx. 40 km; the edge of the outer basin extends to 85-km diameter. The morphological divide between the inner and outer crater is termed the inner ring or peak ring. Little is known about the nature of the inner ring. Seismic reflection data show that the underlying basement is modestly uplifted; however, it is unclear whether the pristine surface expression of the inner ring was elevated above the floor of the outer crater.

  3. Masers in Disks due to Gravitational Instabilities

    NASA Astrophysics Data System (ADS)

    Mejia, A. C.; Durisen, R. H.; Pickett, B. K.; Hartquist, T. W.

    2001-12-01

    Evidence suggests that some masers associated with massive protostars may originate in the outer regions of large circumstellar disks, at radii of 100's to 1000's of AU from the central mass. This is particularly true for methanol (CH3OH), where linear distributions of masers are found with disk-like kinematics. In 3D hydrodynamics simulations we have made to study the effects of gravitational instabilities in the outer parts of disks around young low-mass stars, the nonlinear development of the instabilities leads to a complex of intersecting spiral shocks, clumps, and arclets within the disk and to significant time-dependent, nonaxisymmetric distortions of the disk surface. A rescaling of our disk simulations to the case of a massive protostar shows that conditions in the disturbed outer disk seem conducive to the appearance of masers if it is viewed edge-on. This work was supported by NASA Origins Program Grant NAGW5-4342, by the Alexander von Humboldt Foundation, and by NASA Planetary Geology and Geophysics Program Grant NAG5-10262.

  4. Ancient impact structures on modern continental shelves: The Chesapeake Bay, Montagnais, and Toms Canyon craters, Atlantic margin of North America

    USGS Publications Warehouse

    Poag, C. Wylie; Plescia, J.B.; Molzer, P.C.

    2002-01-01

    Three ancient impact craters (Chesapeake Bay - 35.7 Ma; Toms Canyon - 35.7 Ma; Montagnais - 51 Ma) and one multiring impact basin (Chicxulub - 65 Ma) are currently known to be buried beneath modern continental shelves. All occur on the passive Atlantic margin of North America in regions extensively explored by seismic reflection surveys in the search for oil and gas reserves. We limit our discussion herein to the three youngest structures. These craters were created by submarine impacts, which produced many structural and morphological features similar in construction, composition, and variability to those documented in well-preserved subaerial and planetary impact craters. The subcircular Chesapeake Bay (diameter 85 km) and ovate Montagnais (diameter 45-50 km) structures display outer-rim scarps, annular troughs, peak rings, inner basins, and central peaks similar to those incorporated in the widely cited conceptual model of complex impact craters. These craters differ in several respects from the model, however. For example, the Montagnais crater lacks a raised lip on the outer rim, the Chesapeake Bay crater displays only small remnants of a raised lip, and both craters contain an unusually thick body of impact breccia. The subtriangular Toms Canyon crater (diameter 20-22 km), on the other hand, contains none of the internal features of a complex crater, nor is it typical of a simple crater. It displays a prominent raised lip on the outer rim, but the lip is present only on the western side of the crater. In addition, each of these craters contains some distinct features, which are not present in one or both of the others. For example, the central peak at Montagnais rises well above the elevation of the outer rim, whereas at Chesapeake Bay, the outer rim is higher than the central peak. The floor of the Toms Canyon crater is marked by parallel deep troughs and linear ridges formed of sedimentary rocks, whereas at Chesapeake Bay, the crater floor contains concentric faults and compression ridges formed in rocks of the crystalline basement. The Chesapeake Bay crater is distinguished further by its cluster of at least 23 adjacent secondary craters. The North American tektite strewn field, a widespread deposit of distal ejecta, is thought to be derived from the Chesapeake Bay impact, perhaps with a small contribution from the Toms Canyon impact. No ejecta field is known to be associated with the Montagnais impact. No immediate major extinction event is directly linked to any of these three impacts. There is evidence, however, that the Chesapeake Bay and Toms Canyon impacts helped initiate a long-term pulse of warm global climate, whose eventual dissipation coincided with an early Oligocene mass extinction event, 2 Ma after the impacts.

  5. Sun-Relative Pointing for Dual-Axis Solar Trackers Employing Azimuth and Elevation Rotations

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

    Riley, Daniel; Hansen, Clifford W.

    Dual axis trackers employing azimuth and elevation rotations are common in the field of photovoltaic (PV) energy generation. Accurate sun-tracking algorithms are widely available. However, a steering algorithm has not been available to accurately point the tracker away from the sun such that a vector projection of the sun beam onto the tracker face falls along a desired path relative to the tracker face. We have developed an algorithm which produces the appropriate azimuth and elevation angles for a dual axis tracker when given the sun position, desired angle of incidence, and the desired projection of the sun beam ontomore » the tracker face. Development of this algorithm was inspired by the need to accurately steer a tracker to desired sun-relative positions in order to better characterize the electro-optical properties of PV and CPV modules.« less

  6. Percutaneous endoscopic intra-annular subligamentous herniotomy for large central disc herniation: a technical case report.

    PubMed

    Lee, Sang-Ho; Choi, Kyung-Chul; Baek, Oon Ki; Kim, Ho Jin; Yoo, Seung-Hwa

    2014-04-01

    Technical case report. To describe the novel technique of percutaneous endoscopic herniotomy using a unilateral intra-annular subligamentous approach for the treatment of large centrally herniated discs. Open discectomy for large central disc herniations may have poor long-term prognosis due to heavy loss of intervertebral disc tissue, segmental instability, and recurrence of pain. Six consecutive patients who presented with back and leg pain, and/or weakness due to a large central disc herniation were treated using percutaneous endoscopic herniotomy with a unilateral intra-annular subligamentous approach. The patients experienced relief of symptoms and intervertebral disc spaces were well maintained. The annular defects were noted to be in the process of healing and recovery. Percutaneous endoscopic unilateral intra-annular subligamentous herniotomy was an effective and affordable minimally invasive procedure for patients with large central disc herniations, allowing preservation of nonpathological intradiscal tissue through a concentric outer-layer annular approach.

  7. A simple compact UHV and high magnetic field compatible inertial nanopositioner

    NASA Astrophysics Data System (ADS)

    Pang, Zongqiang; Li, Xiang; Xu, Lei; Rong, Zhou; Liu, Ruilan

    2015-01-01

    We present a novel simple piezoelectric nanopositioner which just has one piezoelectric scanner tube (PST) and one driving signal, using two short quartz rods and one BeCu spring which form a triangle to press the central shaft and can promise the nanopositioner's rigidity. Applying two pulse inverted voltage signals on the PST's outer and inner electrodes, respectively, according to the principle of piezoelectricity, the PST will elongate or contract suddenly while the central shaft will keep stationary for its inertance, so the central shaft will be sliding a distance relative to quartz rods and spring, and then withdraw the pulse voltages slowly, the central shaft will move upward or downward one step. The heavier of the central shaft, the better moving stability, so the nanopositioner has high output force. Due to its compactness and mechanical stability, it can be easily implanted into some extreme conditions, such as ultrahigh vacuum, ultralow temperature, and high magnetic field.

  8. Testing FlowTracker2 Performance and Wading Rod Flow Disturbance in Laboratory Tow Tanks

    NASA Astrophysics Data System (ADS)

    Fan, X.; Wagenaar, D.

    2016-12-01

    The FlowTracker2 was released in February 2016 by SonTek (Xylem) to be a more feature-rich and technologically advanced replacement to the Original FlowTracker ADV. These instruments are Acoustic Doppler Velocimeters (ADVs) used for taking high-precision wading discharge and velocity measurements. The accuracy of the FlowTracker2 probe was tested in tow tanks at three different facilities: the USGS Hydrologic Instrumentation Facility (HIF), the Swiss Federal Institute for Metrology (METAS), and at the SonTek Research and Development facility. Multiple mounting configurations were examined, including mounting the ADV probe directly to the tow carts, and incorporating the two most-used wading rods for the FlowTracker (round and hex). Tow speeds ranged from 5cm/s to 1.5m/s, and different tow tank seeding schemes and wait times were examined. In addition, the performance of the FlowTracker2 probe in low Signal-to-Noise Ratio (SNR) environments was compared to the Original FlowTracker ADV. Results confirmed that the FlowTracker2 probe itself performed well within the 1%+0.25cm/s accuracy specification advertised. Tows using the wading rods created a reduced measured velocity by 1.3% of the expected velocity due to flow disturbance, a result similar to the Original FlowTracker ADV despite the change in the FlowTracker2 probe design. Finally, due to improvements in its electronics, the FlowTracker2's performance in low SNR tests exceeded that of the Original FlowTracker ADV, showing less standard error in these conditions compared to its predecessor.

  9. Impact of contact lens zone geometry and ocular optics on bifocal retinal image quality

    PubMed Central

    Bradley, Arthur; Nam, Jayoung; Xu, Renfeng; Harman, Leslie; Thibos, Larry

    2014-01-01

    Purpose To examine the separate and combined influences of zone geometry, pupil size, diffraction, apodisation and spherical aberration on the optical performance of concentric zonal bifocals. Methods Zonal bifocal pupil functions representing eye + ophthalmic correction were defined by interleaving wavefronts from separate optical zones of the bifocal. A two-zone design (a central circular inner zone surrounded by an annular outer-zone which is bounded by the pupil) and a five-zone design (a central small circular zone surrounded by four concentric annuli) were configured with programmable zone geometry, wavefront phase and pupil transmission characteristics. Using computational methods, we examined the effects of diffraction, Stiles Crawford apodisation, pupil size and spherical aberration on optical transfer functions for different target distances. Results Apodisation alters the relative weighting of each zone, and thus the balance of near and distance optical quality. When spherical aberration is included, the effective distance correction, add power and image quality depend on zone-geometry and Stiles Crawford Effect apodisation. When the outer zone width is narrow, diffraction limits the available image contrast when focused, but as pupil dilates and outer zone width increases, aberrations will limit the best achievable image quality. With two-zone designs, balancing near and distance image quality is not achieved with equal area inner and outer zones. With significant levels of spherical aberration, multi-zone designs effectively become multifocals. Conclusion Wave optics and pupil varying ocular optics significantly affect the imaging capabilities of different optical zones of concentric bifocals. With two-zone bifocal designs, diffraction, pupil apodisation spherical aberration, and zone size influence both the effective add power and the pupil size required to balance near and distance image quality. Five-zone bifocal designs achieve a high degree of pupil size independence, and thus will provide more consistent performance as pupil size varies with light level and convergence amplitude. PMID:24588552

  10. Ultrastructure and chemical composition of the proboscis hooks of Acanthocephalus lucii (Müller, 1776) (Acanthocephala: Palaeacanthocephala) using X-ray elemental analysis.

    PubMed

    Brázová, Tímea; Poddubnaya, Larisa G; Miss, Noemí Ramírez; Hanzelová, Vladimíra

    2014-12-01

    The ultrastructure and chemical composition of the proboscis hooks and surrounding tegument of Acanthocephalus lucii (Müller, 1776), a parasite of European perch, Perca fluviatilis Linnaeus, were examined using scanning (SEM) and transmission (TEM) electron microscopy and X-ray microanalysis (EDXA). The blade of middle hooks consists of three layers: an outer homogeneous layer, an inner heterogeneous layer and a central core. TEM observation revealed the presence of hollow tubes, which spaced the central core; fibrous inner hook layer surrounded by an electron-dense margin and the basal tegumental layer filled with electron-dense bodies and outer layer. We found for the first time that the so-called 'epidermal covering' surrounding of the exposed hook blade (outer hook layer) is a modified striped portion of the tegumental layer and there are no special contact sites between these two morphologically different structures, i.e. striped layer of the syncytial tegument and following proper outer hook layer, which is a homogeneous, moderately electron-dense layer of -0.3 μm in thickness. The hook root is embedded into subtegumental fibrous layer. X-ray microanalysis of both the surface and internal parts of A. lucii hooks demonstrated the presence of calcium, magnesium, phosphorus and sulphur. The highest concentration of sulphur was recorded at the tip of hooks, whereas the middle part of the hooks was most rich in calcium, phosphorus and magnesium. The proximal part of the hooks contained lower concentrations of sulphur, calcium and phosphorus. In the proboscis tegument, only two elements, calcium and silicon, were found. The differences observed in the chemical composition of the hook 'epidermal covering' and the proboscis tegument support our ultrastructural findings that the hook tegumental covering is a modified structure compared with that of the general proboscis tegument.

  11. Unraveling the Helix Nebula: Its Structure and Knots

    NASA Astrophysics Data System (ADS)

    O'Dell, C. R.; McCullough, Peter R.; Meixner, Margaret

    2004-11-01

    Through Hubble Space Telescope (HST) imaging of the inner part of the main ring of the Helix Nebula, together with CTIO 4 m images of the fainter outer parts, we have a view of unprecedented quality of the nearest bright planetary nebula. These images have allowed us to determine that the main ring of the nebula is composed of an inner disk of about 499" diameter (0.52 pc) surrounded by an outer ring (in reality a torus) of 742" diameter (0.77 pc) whose plane is highly inclined to the plane of the disk. This outer ring is surrounded by an outermost ring of 1500" (1.76 pc) diameter, which is flattened on the side colliding with the ambient interstellar medium. The inner disk has an extended distribution of low-density gas along its rotational axis of symmetry, and the disk is optically thick to ionizing radiation, as is the outer ring. Published radial velocities of the knots provide support for the two-component structure of the main ring of the nebula and for the idea that the knots found there are expanding along with the nebular material from which they recently originated. These velocities indicate a spatial expansion velocity of the inner disk of 40 and 32 km s-1 for the outer ring, which yields expansion ages of 6560 and 12,100 yr, respectively. The outermost ring may be partially ionized through scattered recombination continuum from the inner parts of the nebula, but shocks certainly are occurring in it. This outermost ring probably represents a third period of mass loss by the central star. There is one compact, outer object that is unexplained, showing shock structures indicating a different orientation of the gas flow from that of the nebula. There is a change in the morphology of the knots as a function of the distance from the local ionization front. This supports a scenario in which the knots are formed in or near the ionization front and are then sculpted by the stellar radiation from the central star as the ionization front advances beyond them. Based in part on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. Based in part on observations obtained at the Cerro Tololo Inter-American Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a Cooperative Agreement with the National Science Foundation.

  12. Search for disappearing tracks in proton-proton collisions at √s = 8 TeV

    DOE PAGES

    Khachatryan, V.

    2015-01-19

    In this study, a search is presented for long-lived charged particles that decay within the CMS detector and produce the signature of a disappearing track. Disappearing tracks are identified as those with little or no associated calorimeter energy deposits and with missing hits in the outer layers of the tracker. The search uses proton-proton collision data recorded at √s = 8 TeV that corresponds to an integrated luminosity of 19.5 fb –1. The results of the search are interpreted in the context of the anomaly-mediated supersymmetry breaking (AMSB) model. The number of observed events is in agreement with the backgroundmore » expectation, and limits are set on the cross section of direct electroweak chargino production in terms of the chargino mass and mean proper lifetime. At 95% confidence level, AMSB models with a chargino mass less than 260 GeV, corresponding to a mean proper lifetime of 0.2 ns, are excluded.« less

  13. Optical study of solar tower power plants

    NASA Astrophysics Data System (ADS)

    Eddhibi, F.; Ben Amara, M.; Balghouthi, M.; Guizani, A.

    2015-04-01

    The central receiver technology for electricity generation consists of concentrating solar radiation coming from the solar tracker field into a central receiver surface located on the top of the tower. The heliostat field is constituted of a big number of reflective mirrors; each heliostat tracks the sun individually and reflects the sunlight to a focal point. Therefore, the heliostat should be positioned with high precision in order to minimize optical losses. In the current work, a mathematical model for the analysis of the optical efficiency of solar tower field power plant is proposed. The impact of the different factors which influence the optical efficiency is analyzed. These parameters are mainly, the shading and blocking losses, the cosine effect, the atmospheric attenuation and the spillage losses. A new method for the calculation of blocking and shadowing efficiency is introduced and validated by open literature.

  14. Little gem

    NASA Image and Video Library

    2015-08-03

    This colourful bubble is a planetary nebula called NGC 6818, also known as the Little Gem Nebula. It is located in the constellation of Sagittarius (The Archer), roughly 6000 light-years away from us. The rich glow of the cloud is just over half a light-year across — humongous compared to its tiny central star — but still a little gem on a cosmic scale. When stars like the Sun enter retirement, they shed their outer layers into space to create glowing clouds of gas called planetary nebulae. This ejection of mass is uneven, and planetary nebulae can have very complex shapes. NGC 6818 shows knotty filament-like structures and distinct layers of material, with a bright and enclosed central bubble surrounded by a larger, more diffuse cloud. Scientists believe that the stellar wind from the central star propels the outflowing material, sculpting the elongated shape of NGC 6818. As this fast wind smashes through the slower-moving cloud it creates particularly bright blowouts at the bubble’s outer layers. Hubble previously imaged this nebula back in 1997 with its Wide Field Planetary Camera 2, using a mix of filters that highlighted emission from ionised oxygen and hydrogen (opo9811h). This image, while from the same camera, uses different filters to reveal a different view of the nebula. A version of the image was submitted to the Hubble’s Hidden Treasures image processing competition by contestant Judy Schmidt.

  15. ARM - Midlatitude Continental Convective Clouds (jensen-sonde)

    DOE Data Explorer

    Jensen, Mike; Comstock, Jennifer; Genio, Anthony Del; Giangrande, Scott; Kollias, Pavlos

    2012-01-19

    A major component of the Mid-latitude Continental Convective Clouds Experiment (MC3E) field campaign was the deployment of an enhanced radiosonde array designed to capture the vertical profile of atmospheric state variables (pressure, temperature, humidity wind speed and wind direction) for the purpose of deriving the large-scale forcing for use in modeling studies. The radiosonde array included six sites (enhanced Central Facility [CF-1] plus five new sites) launching radiosondes at 3-6 hour sampling intervals. The network will cover an area of approximately (300)2 km2 with five outer sounding launch sites and one central launch location. The five outer sounding launch sites are: S01 Pratt, KS [ 37.7oN, 98.75oW]; S02 Chanute, KS [37.674, 95.488]; S03 Vici, Oklahoma [36.071, -99.204]; S04 Morris, Oklahoma [35.687, -95.856]; and S05 Purcell, Oklahoma [34.985, -97.522]. Soundings from the SGP Central Facility during MC3E can be retrieved from the regular ARM archive. During routine MC3E operations 4 radiosondes were launched from each of these sites (approx. 0130, 0730, 1330 and 1930 UTC). On days that were forecast to be convective up to four additional launches were launched at each site (approx. 0430, 1030, 1630, 2230 UTC). There were a total of approximately 14 of these high frequency launch days over the course of the experiment.

  16. Spreading dynamics of superposed liquid drops on a spinning disk

    NASA Astrophysics Data System (ADS)

    Sahoo, Subhadarshinee; Orpe, Ashish V.; Doshi, Pankaj

    2018-01-01

    We have experimentally studied simultaneous spreading of superposed drops of two Newtonian liquids on top of a horizontal spinning disk using the flow visualization technique. An inner drop of high surface tension liquid is placed centrally on the disk followed by a drop of outer liquid (lower surface tension) placed exactly above that. The disk is then rotated at a desired speed for a range of volume ratios of two liquids. Such an arrangement of two superposed liquid drops does not affect the spreading behavior of the outer liquid but influences that of the inner liquid significantly. The drop spreads to a larger extent and breaks into more fingers (Nf) as compared to the case where the same liquid is spreading in the absence of outer liquid. The experimentally observed number of fingers is compared with the prediction using available theory for single liquid. It is found that the theory over-predicts the value of Nf for the inner liquid while it is covered by an outer liquid. We provide a theoretical justification for this observation using linear stability analysis. Our analysis demonstrates that for small but finite surface tension ratio of the two liquids, the presence of the outer interface reduces the value of the most unstable wave number which is equivalent to the decrease in the number of fingers observed experimentally. Finally, sustained rotation of the disk leads to the formation of droplets at the tip of the fingers traveling outwards.

  17. Experimental Highlights: Heavy Quark Physics in Heavy-Ion Collisions at RHIC

    DOE PAGES

    Nouicer, Rachid

    2017-03-22

    The discovery at RHIC of large high-p T suppression and flow of electrons from heavy quarks flavors have altered our view of the hot and dense matter formed in central Au + Au collisions at √s NN = 200 GeV. These results suggest a large energy loss and flow of heavy quarks in the hot, dense matter. In recent years, the RHIC experiments upgraded the detectors; (1) PHENIX Collaboration installed silicon vertex tracker (VTX) at midrapidity region and forward silicon vertex tracker (FVTX) at the forward rapidity region, and (2) STAR Collaboration installed the heavy flavor tracker (HFT) and themore » muon telescope detector (MTD) both at the mid-rapidity region. The PHENIX experiments established measurements of ψ (1S ) and ψ (2S ) production as a function of system size, p + p, p + Al, p + Au, and 3He + Au collisions at √s NN = 200 GeV. In p/ 3He + A collisions at forward rapidity, we observe no difference in the ψ (2S )/ψ (1S ) ratio relative to p + p collisions. At backward rapidity, where the comoving particle density is higher, we find that the ψ (2S ) is preferentially suppressed by a factor of two. STAR Collaboration presents the first J/ ψ measurements in the di-muon decay channel in Au + Au at √s NN = 200 GeV at mid-rapidity. In conclusion, we observe a clear J/ψ R AA suppression and qualitatively well described by transport models, including dissociation and regeneration simultaneously.« less

  18. Zero suppression logic of the ALICE muon forward tracker pixel chip prototype PIXAM and associated readout electronics development

    NASA Astrophysics Data System (ADS)

    Flouzat, C.; Değerli, Y.; Guilloux, F.; Orsini, F.; Venault, P.

    2015-05-01

    In the framework of the ALICE experiment upgrade at HL-LHC, a new forward tracking detector, the Muon Forward Tracker (MFT), is foreseen to overcome the intrinsic limitations of the present Muon Spectrometer and will perform new measurements of general interest for the whole ALICE physics. To fulfill the new detector requirements, CMOS Monolithic Active Pixel Sensors (MAPS) provide an attractive trade-off between readout speed, spatial resolution, radiation hardness, granularity, power consumption and material budget. This technology has been chosen to equip the Muon Forward Tracker and also the vertex detector: the Inner Tracking System (ITS). Since few years, an intensive R&D program has been performed on the design of MAPS in the 0.18 μ m CMOS Image Sensor (CIS) process. In order to avoid pile up effects in the experiment, the classical rolling shutter readout system of MAPS has been improved to overcome the readout speed limitation. A zero suppression algorithm, based on a 3 by 3 cluster finding (position and data), has been chosen for the MFT. This algorithm allows adequate data compression for the sensor. This paper presents the large size prototype PIXAM, which represents 1/3 of the final chip, and will focus specially on the zero suppression block architecture. This chip is designed and under fabrication in the 0.18 μ m CIS process. Finally, the readout electronics principle to send out the compressed data flow is also presented taking into account the cluster occupancy per MFT plane for a single central Pb-Pb collision.

  19. Autonomous star tracker based on active pixel sensors (APS)

    NASA Astrophysics Data System (ADS)

    Schmidt, U.

    2017-11-01

    Star trackers are opto-electronic sensors used onboard of satellites for the autonomous inertial attitude determination. During the last years, star trackers became more and more important in the field of the attitude and orbit control system (AOCS) sensors. High performance star trackers are based up today on charge coupled device (CCD) optical camera heads. The Jena-Optronik GmbH is active in the field of opto-electronic sensors like star trackers since the early 80-ties. Today, with the product family ASTRO5, ASTRO10 and ASTRO15, all marked segments like earth observation, scientific applications and geo-telecom are supplied to European and Overseas customers. A new generation of star trackers can be designed based on the APS detector technical features. The measurement performance of the current CCD based star trackers can be maintained, the star tracker functionality, reliability and robustness can be increased while the unit costs are saved.

  20. A likely planet-induced gap in the disc around T Cha

    NASA Astrophysics Data System (ADS)

    Hendler, Nathanial P.; Pinilla, Paola; Pascucci, Ilaria; Pohl, Adriana; Mulders, Gijs; Henning, Thomas; Dong, Ruobing; Clarke, Cathie; Owen, James; Hollenbach, David

    2018-03-01

    We present high-resolution (0.11 × 0.06 arcsec2) 3 mm ALMA observations of the highly inclined transition disc around the star T Cha. Our continuum image reveals multiple dust structures: an inner disc, a spatially resolved dust gap, and an outer ring. When fitting sky-brightness models to the real component of the 3 mm visibilities, we infer that the inner emission is compact (≤1 au in radius), the gap width is between 18 and 28 au, and the emission from the outer ring peaks at ˜36 au. We compare our ALMA image with previously published 1.6 μm VLT/SPHERE imagery. This comparison reveals that the location of the outer ring is wavelength dependent. More specifically, the peak emission of the 3 mm ring is at a larger radial distance than that of the 1.6 μm ring, suggesting that millimeter-sized grains in the outer disc are located farther away from the central star than micron-sized grains. We discuss different scenarios to explain our findings, including dead zones, star-driven photoevaporation, and planet-disc interactions. We find that the most likely origin of the dust gap is from an embedded planet, and estimate - for a single planet scenario - that T Cha's gap is carved by a 1.2MJup planet.

  1. 77 FR 40376 - Outer Continental Shelf, Oil and Gas Lease Sales in the Central Gulf of Mexico Planning Area (CPA...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-09

    ..., archaeological and socioeconomic conditions or conflicts, or other information that might bear upon the potential leasing and development of this area. BOEM also seeks comments on possible conflicts between future OCS... Programs (CMPs). If possible, these comments should identify specific CMP policies of concern, the nature...

  2. 78 FR 52562 - Outer Continental Shelf (OCS), Gulf of Mexico (GOM), Oil and Gas Lease Sales, Central Planning...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-23

    ... Prepare a Supplemental Environmental Impact Statement (EIS). SUMMARY: Consistent with the regulations... Supplemental EIS will update the environmental and socioeconomic analyses in the Gulf of Mexico OCS Oil and Gas... Area Lease Sales 227, 231, 235, 241, and 247, Final Environmental Impact Statement (OCS EIS/EA BOEM...

  3. 76 FR 38676 - Gulf of Mexico (GOM), Outer Continental Shelf (OCS), Central Planning Area (CPA), Oil and Gas...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ... September 2008. SUPPLEMENTARY INFORMATION: BOEMRE developed the Draft SEIS for CPA Lease Sale 216/222 to consider new information made available since completion of the Multisale EIS and 2009-2012 SEIS, including information concerning the Deepwater Horizon event and spill and new regulatory requirements. This Draft SEIS...

  4. 77 FR 51568 - Outer Continental Shelf, Gulf of Mexico, Oil and Gas Lease Sales, Western Planning Area Lease...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-24

    ... Western Planning Area (WPA) Lease Sale 233 and Central Planning Area (CPA) Lease Sale 231 (WPA/CPA... is reopening the scoping comment period. DATES: Scoping comments for this Draft WPA/CPA Supplemental...-opening of the scoping process for the WPA/CPA Supplemental EIS. Throughout the scoping process, Federal...

  5. 77 FR 2991 - Gulf of Mexico (GOM), Outer Continental Shelf (OCS), Central Planning Area (CPA), Oil and Gas...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-20

    ... circumstances and information arising from, among other things, the Deepwater Horizon event. This Final... Supplemental EIS) is available at BOEM's Internet Web site at http://www.boem.gov/Environmental-Stewardship... visit BOEM's Internet Web site at http://www.gomr.boem.gov/homepg/regulate/environ/libraries.html . FOR...

  6. Interest and preferences for using advanced physical activity tracking devices: results of a national cross-sectional survey

    PubMed Central

    Alley, Stephanie; Schoeppe, Stephanie; Guertler, Diana; Jennings, Cally; Vandelanotte, Corneel

    2016-01-01

    Objectives Pedometers are an effective self-monitoring tool to increase users' physical activity. However, a range of advanced trackers that measure physical activity 24 hours per day have emerged (eg, Fitbit). The current study aims to determine people's current use, interest and preferences for advanced trackers. Design and participants A cross-sectional national telephone survey was conducted in Australia with 1349 respondents. Outcome measures Regression analyses were used to determine whether tracker interest and use, and use of advanced trackers over pedometers is a function of demographics. Preferences for tracker features and reasons for not wanting to wear a tracker are also presented. Results Over one-third of participants (35%) had used a tracker, and 16% are interested in using one. Multinomial regression (n=1257) revealed that the use of trackers was lower in males (OR=0.48, 95% CI 0.36 to 0.65), non-working participants (OR=0.43, 95% CI 0.30 to 0.61), participants with lower education (OR=0.52, 95% CI 0.38 to 0.72) and inactive participants (OR=0.52, 95% CI 0.39 to 0.70). Interest in using a tracker was higher in younger participants (OR=1.73, 95% CI 1.15 to 2.58). The most frequently used tracker was a pedometer (59%). Logistic regression (n=445) revealed that use of advanced trackers compared with pedometers was higher in males (OR=1.67, 95% CI 1.01 to 2.79) and younger participants (OR=2.96, 95% CI 1.71 to 5.13), and lower in inactive participants (OR=0.35, 95% CI 0.19 to 0.63). Over half of current or interested tracker users (53%) prefer to wear it on their wrist, 31% considered counting steps the most important function and 30% regarded accuracy as the most important characteristic. The main reasons for not wanting to use a tracker were, ‘I don't think it would help me’ (39%), and ‘I don't want to increase my activity’ (47%). Conclusions Activity trackers are a promising tool to engage people in self-monitoring a physical activity. Trackers used in physical activity interventions should align with the preferences of target groups, and should be able to be worn on the wrist, measure steps and be accurate. PMID:27388359

  7. Consequences of Location-Dependent Organ of Corti Micro-Mechanics

    PubMed Central

    Liu, Yanju; Gracewski, Sheryl M.; Nam, Jong-Hoon

    2015-01-01

    The cochlea performs frequency analysis and amplification of sounds. The graded stiffness of the basilar membrane along the cochlear length underlies the frequency-location relationship of the mammalian cochlea. The somatic motility of outer hair cell is central for cochlear amplification. Despite two to three orders of magnitude change in the basilar membrane stiffness, the force capacity of the outer hair cell’s somatic motility, is nearly invariant over the cochlear length. It is puzzling how actuators with a constant force capacity can operate under such a wide stiffness range. We hypothesize that the organ of Corti sets the mechanical conditions so that the outer hair cell’s somatic motility effectively interacts with the media of traveling waves—the basilar membrane and the tectorial membrane. To test this hypothesis, a computational model of the gerbil cochlea was developed that incorporates organ of Corti structural mechanics, cochlear fluid dynamics, and hair cell electro-physiology. The model simulations showed that the micro-mechanical responses of the organ of Corti are different along the cochlear length. For example, the top surface of the organ of Corti vibrated more than the bottom surface at the basal (high frequency) location, but the amplitude ratio was reversed at the apical (low frequency) location. Unlike the basilar membrane stiffness varying by a factor of 1700 along the cochlear length, the stiffness of the organ of Corti complex felt by the outer hair cell remained between 1.5 and 0.4 times the outer hair cell stiffness. The Y-shaped structure in the organ of Corti formed by outer hair cell, Deiters cell and its phalange was the primary determinant of the elastic reactance imposed on the outer hair cells. The stiffness and geometry of the Deiters cell and its phalange affected cochlear amplification differently depending on the location. PMID:26317521

  8. X-rays from Eta Carinae

    NASA Technical Reports Server (NTRS)

    Chlebowski, T.; Seward, F. D.; Swank, J.; Szymkowiak, A.

    1984-01-01

    X-ray observations of Eta Car obtained with the high-resolution imager and solid-state spectrometer of the Einstein observatory are reported and interpreted in terms of a two-shell model. A soft component with temperature 5 million K is located in the expanding outer shell, and the hard core component with temperature 80 million K is attributed to the interaction of a high-velocity stellar wind from the massive central object with the inner edge of a dust shell. Model calculations based on comparison with optical and IR data permit estimation of the mass of the outer shell (0.004 solar mass), the mass of the dust shell (3 solar mass), and the total shell expansion energy (less than 2 x 10 to the 49th ergs).

  9. Radio frequency accelerating cavity having slotted irises for damping certain electromagnetic modes

    DOEpatents

    Palmer, Robert B.

    1991-01-01

    An accelerating cavity having one or more iris structures mounted therein for strongly damping unwanted frequencies that are generated in the cavity by bunches of particles in a particle beam that is accelerated through the cavity during its operation. Each of the iris structures is characterized by containing a plurality of radial slots therein that extend from the central aperture through the iris member to the perimeter thereof. The outer end of each of the radial slots includes an enlarged portion that is effective to prevent undesired frequencies from being reflected back into the center aperture of the iris member. Waveguide means connect the outer ends of the radial slots to frequency damping means or to a dump or dumps.

  10. Mechanical seal with textured sidewall

    DOEpatents

    Khonsari, Michael M.; Xiao, Nian

    2017-02-14

    The present invention discloses a mating ring, a primary ring, and associated mechanical seal having superior heat transfer and wear characteristics. According to an exemplary embodiment of the present invention, one or more dimples are formed onto the cylindrical outer surface of a mating ring sidewall and/or a primary ring sidewall. A stationary mating ring for a mechanical seal assembly is disclosed. Such a mating ring comprises an annular body having a central axis and a sealing face, wherein a plurality of dimples are formed into the outer circumferential surface of the annular body such that the exposed circumferential surface area of the annular body is increased. The texture added to the sidewall of the mating ring yields superior heat transfer and wear characteristics.

  11. Development of a bidirectional ring thermal actuator

    NASA Astrophysics Data System (ADS)

    Stevenson, Mathew; Yang, Peng; Lai, Yongjun; Mechefske, Chris

    2007-10-01

    A new planar micro electrothermal actuator capable of bidirectional rotation is presented. The ring thermal actuator has a wheel-like geometry with eight arms connecting an outer ring to a central hub. Thermal expansion of the arms results in a rotation of the outer ring about its center. An analytical model is developed for the electrothermal and thermal-mechanical aspects of the actuator's operation. Finite element analysis is used to validate the analytic study. The actuator has been fabricated using the multi-user MEMS process and experimental displacement results are compared with model predictions. Experiments show a possible displacement of 7.4 µm in each direction. Also, by switching the current between the arms it is possible to achieve an oscillating motion.

  12. Precision Pointing Control System (PPCS) star tracker test

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Tests performed on the TRW precision star tracker are described. The unit tested was a two-axis gimballed star tracker designed to provide star LOS data to an accuracy of 1 to 2 sec. The tracker features a unique bearing system and utilizes thermal and mechanical symmetry techniques to achieve high precision which can be demonstrated in a one g environment. The test program included a laboratory evaluation of tracker functional operation, sensitivity, repeatibility, and thermal stability.

  13. Small star trackers for modern space vehicles

    NASA Astrophysics Data System (ADS)

    Kouzmin, Vladimir; Jushkov, Vladimir; Zaikin, Vladimir

    2017-11-01

    Based on experience of many years creation of spacecrafts' star trackers with diversified detectors (from the first star trackers of 60's to tens versions of star trackers in the following years), using technological achievements in the field of optics and electronics the NPP "Geofizika-Cosmos" has provided celestial orientation for all the space vehicles created in Russia and now has developed a series of new star trackers with CCD matrix and special processors, which are able to meet needs in celestial orientation of the modern spacecrafts for the nearest 10-15 years. In the given article the main characteristics and description of some star trackers' versions are presented. The star trackers have various levels of technical characteristics and use both combined (Russian and foreign) procurement parts, and only national (Russian) procurement parts for the main units.

  14. Large area directly heated lanthanum hexaboride cathode structure having predetermined emission profile

    DOEpatents

    Leung, Ka-Ngo; Gordon, K.C.; Kippenhan, D.O.; Purgalis, P.; Moussa, D.; Williams, M.D.; Wilde, S.B.; West, M.W.

    1987-10-16

    A large area directly heated lanthanum hexaboride (LaB/sub 6/) cathode system is disclosed. The system comprises a LaB/sub 6/ cathode element generally circular in shape about a central axis. The cathode element has a head with an upper substantially planar emission surface, and a lower downwardly and an intermediate body portion which diminishes in cross-section from the head towards the base of the cathode element. A central rod is connected to the base of the cathode element and extends along the central axis. Plural upstanding spring fingers are urged against an outer peripheral contact surface of the head end to provide a mechanical and electrical connection to the cathode element. 7 figs

  15. The Outer Profile of the Draco Dwarf Spheroidal Galaxy: Measuring the Mass-Loss Rate

    NASA Astrophysics Data System (ADS)

    Armandroff, Taft; Pryor, Carlton; Olszewski, Edward

    1999-02-01

    The existence and properties of dark matter in dwarf galaxies have fundamental implications for cosmology and galaxy formation. We are engaged in a long-term effort to observe and model the structure, kinematics, and mass-to-light ratios of the Draco and UMi dwarf spheroidal (dSph) galaxies. Here we propose to extend our work with a search for outlying members and tidal tails of the Draco dSph galaxy, motivated by observational, theoretical, and technical advances. Recent sophisticated modeling of tidal interactions with the Galactic potential clarifies the interpretation of tidal tails and shows how to calculate the rate at which stars have been lost from a dSph or globular from the density profile of the tidal debris. Also, the radius of the transition between bound and unbound stars yields the outer boundary and total mass of the dark matter halos in the dSphs. While central mass densities and central mass-to-light ratios are generally available for dSphs, determination of their total masses (like those of any galaxy) has remained elusive. We will map a 24 square degree area along the major axis of Draco, plus six square degrees of background. Use of a 3-filter technique will result in an unprecedentedly clean census of distant Draco stars and, thus, a major-axis density profile to a radius of ~6°. Our long-term goal is to investigate the kinematics of the outer members and tidal-tail stars in order to compare in detail with the models.

  16. Pars Plana Vitrectomy with Internal Limiting Membrane Peeling for Nontractional Diabetic Macular Edema.

    PubMed

    Ulrich, Jan Niklas

    2017-01-01

    Diabetes mellitus remains the leading cause of blindness among working age Americans with diabetic macular edema being the most common cause for moderate and severe vision loss. To investigate the anatomical and visual benefits of pars plana vitrectomy with inner limiting membrane peeling in patients with nontractional diabetic macular edema as well as correlation of integrity of outer retinal layers on spectral domain optical coherence tomography to visual outcomes. We retrospectively reviewed the charts of 42 diabetic patients that underwent vitrectomy with internal limiting membrane peeling for nontractional diabetic macula edema. The integrity of outer retinal layers was evaluated and preoperative central macular thickness and visual acuity were compared with data at 1 month, 3 months and 6 months postoperatively. The student t-test was used to compare the groups. 31 eyes were included. While no differences were seen at 1 and 3 months, there was significant improvement of both central macular thickness and visual acuity at the 6 months follow up visit compared to preoperatively (357, 427 microns; p=0.03. 20/49, 20/82; p=0.03) . Patients with intact external limiting membrane and ellipsoid zone had better preoperative vision than patients with outer retinal layer irregularities (20/54, 20/100; p=0.03) and greater visual gains postoperatively (20/33, p<0.001 versus 20/81; p=non-significant). Pars plana vitrectomy with internal limiting membrane peeling can improve retinal anatomy and visual acuity in patients with nontractional diabetic macular edema. Spectral domain optical coherence tomography may help identify patients with potential for visual improvement.

  17. Thinking about feathers: Adaptations of Golden Eagle rectrices

    USGS Publications Warehouse

    Ellis, D.H.; Lish, J.W.

    2006-01-01

    The striking black and white plumage of the juvenile Golden Eagle (Aquila chrysaetos) provides an excellent opportunity to examine the possible selective forces influencing the strategic placement of dark pigment in birds. The conflict between opposing selective pressures (first, toward large white patches, which may allay aggression in adults, and second, toward dark plumage to promote camouflage and limit solar and abrasive wear) provides the stage whereon are revealed a score of pigmentation traits of potential adaptive value. The general pigmentation trend is for zones that are more exposed to the sun to be darker than elsewhere. More specifically: (1) for rectrices and remiges, outer webs are darker than inner; (2) for those few feathers (e.g., central rectrices, some scapulars, and some tertials), where both inner and outer webs are heavily and nearly equally solar exposed, pigmentation is supplied similarly on both webs; (3) outermost primaries and rectrices are darkest of all and are structurally similar; (4) for central rectrices, subject to high levels of abrasion with substrate, the tip is paler (resultant flexibility may limit breakage); and (5) pigment is heavier along or on the rachis than on the webs. Many of the traits listed above for the Golden Eagle are also found in other families of birds. Traits of the tail common to many species were a terminal pale tip, a subterminal dark band, rachis darker than vane, and outer webs darker than inner for both remiges and rectrices. The most widespread traits likely have adaptive value. ?? 2006 The Raptor Research Foundation, Inc.

  18. Dual mode scanner-tracker

    NASA Astrophysics Data System (ADS)

    Mongeon, R. J.

    1984-11-01

    The beam of a laser radar is moved over the field of view by means of a pair of scanner/trackers arranged in cascade along the laser beam. One of the scanner/trackers operates at high speed, with high resolution and a wide field and is located in the demagnified portion of the laser beam. The two scanner/trackers complement each other to achieve high speed, high resolution scanning as well as tracking of moving targets. A beam steering telescope for an airborne laser radar which incorporates the novel dual mode scanner/tracker is also shown. The other scanner/tracker operates at low speed with low resolution and a wide field and is located in the magnified portion of the laser beam.

  19. A Novel Performance Evaluation Methodology for Single-Target Trackers.

    PubMed

    Kristan, Matej; Matas, Jiri; Leonardis, Ales; Vojir, Tomas; Pflugfelder, Roman; Fernandez, Gustavo; Nebehay, Georg; Porikli, Fatih; Cehovin, Luka

    2016-11-01

    This paper addresses the problem of single-target tracker performance evaluation. We consider the performance measures, the dataset and the evaluation system to be the most important components of tracker evaluation and propose requirements for each of them. The requirements are the basis of a new evaluation methodology that aims at a simple and easily interpretable tracker comparison. The ranking-based methodology addresses tracker equivalence in terms of statistical significance and practical differences. A fully-annotated dataset with per-frame annotations with several visual attributes is introduced. The diversity of its visual properties is maximized in a novel way by clustering a large number of videos according to their visual attributes. This makes it the most sophistically constructed and annotated dataset to date. A multi-platform evaluation system allowing easy integration of third-party trackers is presented as well. The proposed evaluation methodology was tested on the VOT2014 challenge on the new dataset and 38 trackers, making it the largest benchmark to date. Most of the tested trackers are indeed state-of-the-art since they outperform the standard baselines, resulting in a highly-challenging benchmark. An exhaustive analysis of the dataset from the perspective of tracking difficulty is carried out. To facilitate tracker comparison a new performance visualization technique is proposed.

  20. Wellbeing in the Making: Peoples' Experiences with Wearable Activity Trackers.

    PubMed

    Karapanos, Evangelos; Gouveia, Rúben; Hassenzahl, Marc; Forlizzi, Jodi

    Wearable activity trackers have become a viable business opportunity. Nevertheless, research has raised concerns over their potentially detrimental effects on wellbeing. For example, a recent study found that while counting steps with a pedometer increased steps taken throughout the day, at the same time it decreased the enjoyment people derived from walking. This poses a serious threat to the incorporation of healthy routines into everyday life. Most studies aim at proving the effectiveness of activity trackers. In contrast, a wellbeing-oriented perspective calls for a deeper understanding of how trackers create and mediate meaningful experiences in everyday life. We present a study of real life experiences with three wearable activity trackers: Fitbit , Jawbone Up and Nike  +  Fuelband . Using need fulfillment as a theoretical lens, we study recent, memorable experiences submitted by 133 users of activity trackers. We reveal a two-dimensional structure of users' experience driven by the needs of physical thriving or relatedness. Our qualitative findings further show a nuanced picture of the adoption of activity trackers and their impact on wellbeing. For instance, while reflection about own exercising practices lost its relevance over time, users continued to wear the tracker to document and collect their runs. More than just supporting behavioral change, we find trackers to provide multiple psychological benefits. For instance, they enhance feelings of autonomy as people gain more control about their exercising regime. Others experience relatedness, when family members purchase a tracker for relatives and join them in their efforts towards a better, healthier self. The study highlights that activity trackers can be more than "tools" to change behavior. Through incorporation in daily life, they offer new social experiences, new ways of boosting our self-esteem and getting closer to our ideal selves.

  1. Monolithic pixel development in TowerJazz 180 nm CMOS for the outer pixel layers in the ATLAS experiment

    NASA Astrophysics Data System (ADS)

    Berdalovic, I.; Bates, R.; Buttar, C.; Cardella, R.; Egidos Plaja, N.; Hemperek, T.; Hiti, B.; van Hoorne, J. W.; Kugathasan, T.; Mandic, I.; Maneuski, D.; Marin Tobon, C. A.; Moustakas, K.; Musa, L.; Pernegger, H.; Riedler, P.; Riegel, C.; Schaefer, D.; Schioppa, E. J.; Sharma, A.; Snoeys, W.; Solans Sanchez, C.; Wang, T.; Wermes, N.

    2018-01-01

    The upgrade of the ATLAS tracking detector (ITk) for the High-Luminosity Large Hadron Collider at CERN requires the development of novel radiation hard silicon sensor technologies. Latest developments in CMOS sensor processing offer the possibility of combining high-resistivity substrates with on-chip high-voltage biasing to achieve a large depleted active sensor volume. We have characterised depleted monolithic active pixel sensors (DMAPS), which were produced in a novel modified imaging process implemented in the TowerJazz 180 nm CMOS process in the framework of the monolithic sensor development for the ALICE experiment. Sensors fabricated in this modified process feature full depletion of the sensitive layer, a sensor capacitance of only a few fF and radiation tolerance up to 1015 neq/cm2. This paper summarises the measurements of charge collection properties in beam tests and in the laboratory using radioactive sources and edge TCT. The results of these measurements show significantly improved radiation hardness obtained for sensors manufactured using the modified process. This has opened the way to the design of two large scale demonstrators for the ATLAS ITk. To achieve a design compatible with the requirements of the outer pixel layers of the tracker, a charge sensitive front-end taking 500 nA from a 1.8 V supply is combined with a fast digital readout architecture. The low-power front-end with a 25 ns time resolution exploits the low sensor capacitance to reduce noise and analogue power, while the implemented readout architectures minimise power by reducing the digital activity.

  2. How Accurate Is Your Activity Tracker? A Comparative Study of Step Counts in Low-Intensity Physical Activities

    PubMed Central

    2017-01-01

    Background As commercially available activity trackers are being utilized in clinical trials, the research community remains uncertain about reliability of the trackers, particularly in studies that involve walking aids and low-intensity activities. While these trackers have been tested for reliability during walking and running activities, there has been limited research on validating them during low-intensity activities and walking with assistive tools. Objective The aim of this study was to (1) determine the accuracy of 3 Fitbit devices (ie, Zip, One, and Flex) at different wearing positions (ie, pants pocket, chest, and wrist) during walking at 3 different speeds, 2.5, 5, and 8 km/h, performed by healthy adults on a treadmill; (2) determine the accuracy of the mentioned trackers worn at different sites during activities of daily living; and (3) examine whether intensity of physical activity (PA) impacts the choice of optimal wearing site of the tracker. Methods We recruited 15 healthy young adults to perform 6 PAs while wearing 3 Fitbit devices (ie, Zip, One, and Flex) on their chest, pants pocket, and wrist. The activities include walking at 2.5, 5, and 8 km/h, pushing a shopping cart, walking with aid of a walker, and eating while sitting. We compared the number of steps counted by each tracker with gold standard numbers. We performed multiple statistical analyses to compute descriptive statistics (ie, ANOVA test), intraclass correlation coefficient (ICC), mean absolute error rate, and correlation by comparing the tracker-recorded data with that of the gold standard. Results All the 3 trackers demonstrated good-to-excellent (ICC>0.75) correlation with the gold standard step counts during treadmill experiments. The correlation was poor (ICC<0.60), and the error rate was significantly higher in walker experiment compared to other activities. There was no significant difference between the trackers and the gold standard in the shopping cart experiment. The wrist worn tracker, Flex, counted several steps when eating (P<.01). The chest tracker was identified as the most promising site to capture steps in more intense activities, while the wrist was the optimal wearing site in less intense activities. Conclusions This feasibility study focused on 6 PAs and demonstrated that Fitbit trackers were most accurate when walking on a treadmill and least accurate during walking with a walking aid and for low-intensity activities. This may suggest excluding participants with assistive devices from studies that focus on PA interventions using commercially available trackers. This study also indicates that the wearing site of the tracker is an important factor impacting the accuracy performance. A larger scale study with a more diverse population, various activity tracker vendors, and a larger activity set are warranted to generalize our results. PMID:28801304

  3. Precision Attitude Determination System (PADS) system design and analysis: Single-axis gimbal star tracker

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The feasibility is evaluated of an evolutionary development for use of a single-axis gimbal star tracker from prior two-axis gimbal star tracker based system applications. Detailed evaluation of the star tracker gimbal encoder is considered. A brief system description is given including the aspects of tracker evolution and encoder evaluation. System analysis includes evaluation of star availability and mounting constraints for the geosynchronous orbit application, and a covariance simulation analysis to evaluate performance potential. Star availability and covariance analysis digital computer programs are included.

  4. Controlling beech root and stump sprouts using the cut-stump treatment

    Treesearch

    Jeffery D. Kochenderfer; James N. Kochenderfer; Gary W. Miller

    2006-01-01

    Application costs and efficacy were determined for cut-stump treatments applied to American beech (Fagus grandifolia Ehrh.) to control root and stump sprouts in central West Virginia. Glyphosate as Glypro (53.8%) was applied to the outer 2 in. of beech stumps from trees >6.0-in. dbh within 1 hour after cutting. In addition to treatment plots,...

  5. Elemental concentrations in foliage of red maple, red oak, and white oak in relation to atmospheric deposition in Pennsylvania

    Treesearch

    D. D. Davis; J. M. Skelly; B. L. Nash

    1995-01-01

    Foliage was sampled in June and late August-early September in 1988 and 1989 from the outer crowns of codominant red maple (Acer rubrum L.), northern red oak (Quercus rubra L.), and white oak (Q. alba L.) trees in forest stands along an atmospheric deposition gradient in north-central Pennsylvania. Leaf samples...

  6. Hermetic aluminum radio frequency interconnection and method for making

    DOEpatents

    Kilgo, Riley D.; Kovacic, Larry; Brow, Richard K.

    2000-01-01

    The present invention provides a light-weight, hermetic coaxial radio-frequency (RF) interconnection having an electrically conductive outer housing made of aluminum or an aluminum alloy, a central electrical conductor made of ferrous or non-ferrous material, and a cylinder of dielectric material comprising a low-melting-temperature, high-thermal-expansion aluminophosphate glass composition for hermetically sealing between the aluminum-alloy outer housing and the ferrous or non-ferrous center conductor. The entire RF interconnection assembly is made permanently hermetic by thermally fusing the center conductor, glass, and housing concurrently by bringing the glass to the melt point by way of exposure to an atmospheric temperature sufficient to melt the glass, less than 540.degree. C., but that does not melt the center conductor or the outer aluminum or aluminum alloy housing. The composition of the glass used is controlled to provide a suitable low dielectric constant so that an appropriate electrical characteristic impedance, for example 50 ohms, can be achieved for an electrical interconnection that performs well at high radio frequencies and also provides an interconnection maintaining a relatively small physical size.

  7. Self-assembled clusters of spheres related to spherical codes.

    PubMed

    Phillips, Carolyn L; Jankowski, Eric; Marval, Michelle; Glotzer, Sharon C

    2012-10-01

    We consider the thermodynamically driven self-assembly of spheres onto the surface of a central sphere. This assembly process forms self-limiting, or terminal, anisotropic clusters (N-clusters) with well-defined structures. We use Brownian dynamics to model the assembly of N-clusters varying in size from two to twelve outer spheres and free energy calculations to predict the expected cluster sizes and shapes as a function of temperature and inner particle diameter. We show that the arrangements of outer spheres at finite temperatures are related to spherical codes, an ideal mathematical sequence of points corresponding to the densest possible sphere packings. We demonstrate that temperature and the ratio of the diameters of the inner and outer spheres dictate cluster morphology. We present a surprising result for the equilibrium structure of a 5-cluster, for which the square pyramid arrangement is preferred over a more symmetric structure. We show this result using Brownian dynamics, a Monte Carlo simulation, and a free energy approximation. Our results suggest a promising way to assemble anisotropic building blocks from constituent colloidal spheres.

  8. Green Space and Deaths Attributable to the Urban Heat Island Effect in Ho Chi Minh City.

    PubMed

    Dang, Tran Ngoc; Van, Doan Quang; Kusaka, Hiroyuki; Seposo, Xerxes T; Honda, Yasushi

    2018-04-01

    To quantify heat-related deaths in Ho Chi Minh City, Vietnam, caused by the urban heat island (UHI) and explore factors that may alleviate the impact of UHIs. We estimated district-specific meteorological conditions from 2010 to 2013 using the dynamic downscaling model and calculated the attributable fraction and number of mortalities resulting from the total, extreme, and mild heat in each district. The difference in attributable fraction of total heat between the central and outer districts was classified as the attributable fraction resulting from the UHI. The association among attributable fraction, attributable number with a green space, population density, and budget revenue of each district was then explored. The temperature-mortality relationship between the central and outer areas was almost identical. The attributable fraction resulting from the UHI was 0.42%, which was contributed by the difference in temperature distribution between the 2 areas. Every 1-square-kilometer increase in green space per 1000 people can prevent 7.4 deaths caused by heat. Green space can alleviate the impacts of UHIs, although future studies conducting a heath economic evaluation of tree planting are warranted.

  9. Development of a spinning wave heat engine

    NASA Technical Reports Server (NTRS)

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

    1982-01-01

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

  10. Green Space and Deaths Attributable to the Urban Heat Island Effect in Ho Chi Minh City

    PubMed Central

    Van, Doan Quang; Kusaka, Hiroyuki; Seposo, Xerxes T.; Honda, Yasushi

    2018-01-01

    Objectives. To quantify heat-related deaths in Ho Chi Minh City, Vietnam, caused by the urban heat island (UHI) and explore factors that may alleviate the impact of UHIs. Methods. We estimated district-specific meteorological conditions from 2010 to 2013 using the dynamic downscaling model and calculated the attributable fraction and number of mortalities resulting from the total, extreme, and mild heat in each district. The difference in attributable fraction of total heat between the central and outer districts was classified as the attributable fraction resulting from the UHI. The association among attributable fraction, attributable number with a green space, population density, and budget revenue of each district was then explored. Results. The temperature–mortality relationship between the central and outer areas was almost identical. The attributable fraction resulting from the UHI was 0.42%, which was contributed by the difference in temperature distribution between the 2 areas. Every 1-square-kilometer increase in green space per 1000 people can prevent 7.4 deaths caused by heat. Conclusions. Green space can alleviate the impacts of UHIs, although future studies conducting a heath economic evaluation of tree planting are warranted. PMID:29072938

  11. Phagocytosis of photoreceptor outer segments by transplanted human neural stem cells as a neuroprotective mechanism in retinal degeneration.

    PubMed

    Cuenca, Nicolás; Fernández-Sánchez, Laura; McGill, Trevor J; Lu, Bin; Wang, Shaomei; Lund, Raymond; Huhn, Stephen; Capela, Alexandra

    2013-10-15

    Transplantation of human central nervous system stem cells (HuCNS-SC) into the subretinal space of Royal College of Surgeons (RCS) rats preserves photoreceptors and visual function. To explore possible mechanism(s) of action underlying this neuroprotective effect, we performed a detailed morphologic and ultrastructure analysis of HuCNS-SC transplanted retinas. The HuCNS-SC were transplanted into the subretinal space of RCS rats. Histologic examination of the transplanted retinas was performed by light and electron microscopy. Areas of the retina adjacent to HuCNS-SC graft (treated regions) were analyzed and compared to control sections obtained from the same retina, but distant from the transplant site (untreated regions). The HuCNS-SC were detected as a layer of STEM 121 immunopositive cells in the subretinal space. In treated regions, preserved photoreceptor nuclei, as well as inner and outer segments were identified readily. In contrast, classic signs of degeneration were observed in the untreated regions. Interestingly, detailed ultrastructure analysis revealed a striking preservation of the photoreceptor-bipolar-horizontal cell synaptic contacts in the outer plexiform layer (OPL) of treated areas, in stark contrast with untreated areas. Finally, the presence of phagosomes and vesicles exhibiting the lamellar structure of outer segments also was detected within the cytosol of HuCNS-SC, indicating that these cells have phagocytic capacity in vivo. This study reveals the novel finding that preservation of specialized synaptic contacts between photoreceptors and second order neurons, as well as phagocytosis of photoreceptor outer segments, are potential mechanism(s) of HuCNS-SC transplantation, mediating functional rescue in retinal degeneration.

  12. Simulations of Ar gas-puff Z-pinch radiation sources with double shells and central jets on the Z generator

    NASA Astrophysics Data System (ADS)

    Tangri, V.; Harvey-Thompson, A. J.; Giuliani, J. L.; Thornhill, J. W.; Velikovich, A. L.; Apruzese, J. P.; Ouart, N. D.; Dasgupta, A.; Jones, B.; Jennings, C. A.

    2016-10-01

    Radiation-magnetohydrodynamic simulations using the non-local thermodynamic equilibrium Mach2-Tabular Collisional-Radiative Equilibrium code in (r, z) geometry are performed for two pairs of recent Ar gas-puff Z-pinch experiments on the refurbished Z generator with an 8 cm diameter nozzle. One pair of shots had an outer-to-inner shell mass ratio of 1:1.6 and a second pair had a ratio of 1:1. In each pair, one of the shots had a central jet. The experimental trends in the Ar K-shell yield and power are reproduced in the calculations. However, the K-shell yield and power are significantly lower than the other three shots for the case of a double-shell puff of 1:1 mass ratio and no central jet configuration. Further simulations of a hypothetical experiment with the same relative density profile of this configuration, but higher total mass, show that the coupled energy from the generator and the K-shell yield can be increased to levels achieved in the other three configurations, but not the K-shell power. Based on various measures of effective plasma radius, the compression in the 1:1 mass ratio and no central jet case is found to be less because the plasma inside the magnetic piston is hotter and of lower density. Because of the reduced density, and the reduced radiation cooling (which is proportional to the square of the density), the core plasma is hotter. Consequently, for the 1:1 outer-to-inner shell mass ratio, the load mass controls the yield and the center jet controls the power.

  13. Ceramic end seal design for high temperature high voltage nuclear instrumentation cables

    DOEpatents

    Meiss, James D.; Cannon, Collins P.

    1979-01-01

    A coaxial, hermetically sealed end structure is described for electrical instrumentation cables. A generally tubular ceramic body is hermetically sealed within a tubular sheath which is in turn sealed to the cable sheath. One end of the elongated tubular ceramic insulator is sealed to a metal end cap. The other end of the elongated tubular insulator has an end surface which is shaped concave relative to a central conductor which extends out of this end surface. When the end seal is hermetically sealed to an instrumentation cable device and the central conductor is maintained at a high positive potential relative to the tubular metal sheath, the electric field between the central conductor and the outer sheath tends to collect electrons from the concave end surface of the insulator. This minimizes breakdown pulse noise generation when instrumentation potentials are applied to the central conductor.

  14. A novel adaptive sun tracker for spacecraft solar panel based on hybrid unsymmetric composite laminates

    NASA Astrophysics Data System (ADS)

    Wu, Zhangming; Li, Hao

    2017-11-01

    This paper proposes a novel adaptive sun tracker which is constructed by hybrid unsymmetric composite laminates. The adaptive sun tracker could be applied on spacecraft solar panels to increase their energy efficiency through decreasing the inclined angle between the sunlight and the solar panel normal. The sun tracker possesses a large rotation freedom and its rotation angle depends on the laminate temperature, which is affected by the light condition in the orbit. Both analytical model and finite element model (FEM) are developed for the sun tracker to predict its rotation angle in different light conditions. In this work, the light condition of the geosynchronous orbit on winter solstice is considered in the numerical prediction of the temperatures of the hybrid laminates. The final inclined angle between the sunlight and the solar panel normal during a solar day is computed using the finite element model. Parametric study of the adaptive sun tracker is conducted to improve its capacity and effectiveness of sun tracking. The improved adaptive sun tracker is lightweight and has a state-of-the-art design. In addition, the adaptive sun tracker does not consume any power of the solar panel, since it has no electrical driving devices. The proposed adaptive sun tracker provides a potential alternative to replace the traditional sophisticated electrical driving mechanisms for spacecraft solar panels.

  15. A family of models for spherical stellar systems

    NASA Technical Reports Server (NTRS)

    Tremaine, Scott; Richstone, Douglas O.; Byun, Yong-Ik; Dressler, Alan; Faber, S. M.; Grillmair, Carl; Kormendy, John; Lauer, Tod R.

    1994-01-01

    We describe a one-parameter family of models of stable sperical stellar systems in which the phase-space distribution function depends only on energy. The models have similar density profiles in their outer parts (rho propotional to r(exp -4)) and central power-law density cusps, rho proportional to r(exp 3-eta), 0 less than eta less than or = 3. The family contains the Jaffe (1983) and Hernquist (1990) models as special cases. We evaluate the surface brightness profile, the line-of-sight velocity dispersion profile, and the distribution function, and discuss analogs of King's core-fitting formula for determining mass-to-light ratio. We also generalize the models to a two-parameter family, in which the galaxy contains a central black hole; the second parameter is the mass of the black hole. Our models can be used to estimate the detectability of central black holes and the velocity-dispersion profiles of galaxies that contain central cusps, with or without a central black hole.

  16. Validation of an Electronic System for Recording Medical Student Patient Encounters

    PubMed Central

    Nkoy, Flory L.; Petersen, Sarah; Matheny Antommaria, Armand H.; Maloney, Christopher G.

    2008-01-01

    The Liaison Committee for Medical Education requires monitoring of the students’ clinical experiences. Student logs, typically used for this purpose, have a number of limitations. We used an electronic system called Patient Tracker to passively generate student encounter data. The data contained in Patient Tracker was compared to the information reported on student logs and data abstracted from the patients’ charts. Patient Tracker identified 30% more encounters than the student logs. Compared to the student logs, Patient Tracker contained a higher average number of diagnoses per encounter (2.28 vs. 1.03, p<0.01). The diagnostic data contained in Patient Tracker was also more accurate under 4 different definitions of accuracy. Only 1.3% (9/677) of diagnoses in Patient Tracker vs. 16.9% (102/601) diagnoses in the logs could not be validated in patients’ charts (p<0.01). Patient Tracker is a more effective and accurate tool for documenting student clinical encounters than the conventional student logs. PMID:18999155

  17. Novel approach to improve the attitude update rate of a star tracker.

    PubMed

    Zhang, Shuo; Xing, Fei; Sun, Ting; You, Zheng; Wei, Minsong

    2018-03-05

    The star tracker is widely used in attitude control systems of spacecraft for attitude measurement. The attitude update rate of a star tracker is important to guarantee the attitude control performance. In this paper, we propose a novel approach to improve the attitude update rate of a star tracker. The electronic Rolling Shutter (RS) imaging mode of the complementary metal-oxide semiconductor (CMOS) image sensor in the star tracker is applied to acquire star images in which the star spots are exposed with row-to-row time offsets, thereby reflecting the rotation of star tracker at different times. The attitude estimation method with a single star spot is developed to realize the multiple attitude updates by a star image, so as to reach a high update rate. The simulation and experiment are performed to verify the proposed approaches. The test results demonstrate that the proposed approach is effective and the attitude update rate of a star tracker is increased significantly.

  18. Retinal Structure Measurements as Inclusion Criteria for Stem Cell-Based Therapies of Retinal Degenerations.

    PubMed

    Jacobson, Samuel G; Matsui, Rodrigo; Sumaroka, Alexander; Cideciyan, Artur V

    2016-04-01

    We reviewed and illustrated the most optimal retinal structural measurements to make in stem cell clinical trials. Optical coherence tomography (OCT) and autofluorescence (AF) imaging were used to evaluate patients with severe visual loss from nonsyndromic and syndromic retinitis pigmentosa (RP), ABCA4-Stargardt disease, and nonneovascular age-related macular degeneration (AMD). Outer nuclear layer (ONL), rod outer segment (ROS) layer, inner retina, ganglion cell layer (GCL), and nerve fiber layer (NFL) thicknesses were quantified. All patients had severely reduced visual acuities. Retinitis pigmentosa patients had limited visual fields; maculopathy patients had central scotomas with retained peripheral function. For the forms of RP illustrated, there was detectable albeit severely reduced ONL across the scanned retina, and normal or hyperthick GCL and NFL. Maculopathy patients had no measurable ONL centrally; it became detectable with eccentricity. Some maculopathy patients showed unexpected GCL losses. Autofluorescence imaging illustrated central losses of RPE integrity. A hypothetical scheme to relate patient data with different phases of retinal remodeling in animal models of retinal degeneration was presented. Stem cell science is advancing, but it is not too early to open the discussion of criteria for patient selection and monitoring. Available clinical tools, such as OCT and AF imaging, can provide inclusion/exclusion criteria and robust objective outcomes. Accepting that early trials may not lead to miraculous cures, we should be prepared to know why-scientifically and clinically-so we can improve subsequent trials. We also must determine if retinal remodeling is an impediment to efficacy.

  19. The internal/external issue what is an outer object? Another person as object and as separate other in object relations models.

    PubMed

    Zachrisson, Anders

    2013-01-01

    The question of what we mean by the term outer object has its roots in the epistemological foundation of psychoanalysis. From the very beginning, Freud's view was Kantian, and psychoanalysis has kept that stance, as it seems. The author reviews the internal/external issue in Freud's thinking and in the central object relations theories (Klein, Winnicott, and Bion). On this background he proposes a simple model to differentiate the concept of object along one central dimension: internal object, external object, and actual person. The main arguments are: (1) there is no direct, unmediated perception of the actual person--the experience of the other is always affected by the perceiver's subjectivity; (2) in intense transference reactions and projections, the perception of the person is dominated by the qualities of an inner object--and the other person "becomes" an external object for the perceiver; (3) when this distortion is less dominating, the other person to a higher degree remains a separate other--a person in his or her own right. Clinical material illustrates these phenomena, and a graphical picture of the model is presented. Finally with the model as background, the author comments on a selection of phenomena and concepts such as unobjectionable transference, "the third position," mourning and loneliness. The way that the internal colours and distorts the external is of course a central preoccupation of psychoanalysis generally. (Spillius et al., 2011, p. 326)

  20. Radio frequency accelerating cavity having slotted irises for damping certain electromagnetic modes

    DOEpatents

    Palmer, R.B.

    1991-05-21

    An accelerating cavity is disclosed having one or more iris structures mounted therein for strongly damping unwanted frequencies that are generated in the cavity by bunches of particles in a particle beam that is accelerated through the cavity during its operation. Each of the iris structures is characterized by containing a plurality of radial slots therein that extend from the central aperture through the iris member to the perimeter thereof. The outer end of each of the radial slots includes an enlarged portion that is effective to prevent undesired frequencies from being reflected back into the center aperture of the iris member. Waveguide means connect the outer ends of the radial slots to frequency damping means or to a dump or dumps. 17 figures.

  1. Open Heavy Flavor and Quarkonia Results at RHIC

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

    Nouicer, Rachid

    RHIC experiments carry out a comprehensive physics program which studies open heavy flavor and quarkonium production in relativistic heavy-ion collisions. The discovery at RHIC of large high-pT suppression and flow of electrons from heavy quarks flavors have altered our view of the hot and dense matter formed in central Au + Au collisions at √S NN = 200 GeV. These results suggest a large energy loss and flow of heavy quarks in the hot, dense matter. In recent years, the RHIC experiments upgraded the detectors; (1) PHENIX Collaboration installed silicon vertex tracker (VTX) at mid-rapidity region and forward silicon vertexmore » tracker (FVTX) at the forward rapidity region, and (2) STAR Collaboration installed the heavy flavor tracker (HFT) and the muon telescope detector (MTD) both at the mid-rapidity region. With these new upgrades, both experiments have collected large data samples. These new detectors enhance the capability of heavy flavor measurements via precision tracking. The PHENIX experiments established measurements of ψ(1S) and ψ(2S) production as a function of system size, p + p, p + Al, p + Au, and 3He + Au collisions at √S NN = 200 GeV. In p/ 3He + A collisions at forward rapidity, we observe no difference in the ψ(2S)/ψ(1S) ratio relative to p + p collisions. At backward rapidity, where the comoving particle density is higher, we find that the ψ(2S) is preferentially suppressed by a factor of two. STAR Collaboration presents the first J/ψ and Υ measurements in the di-muon decay channel in Au + Au collisions at GeV at mid-rapidity at RHIC. Here, we observe clear J/ψ RAA suppression and qualitatively well described by transport models simultaneously accounting for dissociation and regeneration processes.« less

  2. Open Heavy Flavor and Quarkonia Results at RHIC

    NASA Astrophysics Data System (ADS)

    Nouicer, Rachid

    2017-12-01

    RHIC experiments carry out a comprehensive physics program which studies open heavy flavor and quarkonium production in relativistic heavy-ion collisions. The discovery at RHIC of large high-pT suppression and flow of electrons from heavy quarks flavors have altered our view of the hot and dense matter formed in central Au + Au collisions at GeV. These results suggest a large energy loss and flow of heavy quarks in the hot, dense matter. In recent years, the RHIC experiments upgraded the detectors; (1) PHENIX Collaboration installed silicon vertex tracker (VTX) at mid-rapidity region and forward silicon vertex tracker (FVTX) at the forward rapidity region, and (2) STAR Collaboration installed the heavy flavor tracker (HFT) and the muon telescope detector (MTD) both at the mid-rapidity region. With these new upgrades, both experiments have collected large data samples. These new detectors enhance the capability of heavy flavor measurements via precision tracking. The PHENIX experiments established measurements of ψ(1S) and ψ(2S) production as a function of system size, p + p, p + Al, p + Au, and 3He + Au collisions at GeV. In p/3He + A collisions at forward rapidity, we observe no difference in the ψ(2S)/ψ(1S) ratio relative to p + p collisions. At backward rapidity, where the comoving particle density is higher, we find that the ψ(2S) is preferentially suppressed by a factor of two. STAR Collaboration presents the first J/ψ and ϒ measurements in the di-muon decay channel in Au + Au collisions at GeV at mid-rapidity at RHIC. We observe clear J/ψ RAA suppression and qualitatively well described by transport models simultaneously accounting for dissociation and regeneration processes.

  3. Open Heavy Flavor and Quarkonia Results at RHIC

    DOE PAGES

    Nouicer, Rachid

    2017-12-05

    RHIC experiments carry out a comprehensive physics program which studies open heavy flavor and quarkonium production in relativistic heavy-ion collisions. The discovery at RHIC of large high-pT suppression and flow of electrons from heavy quarks flavors have altered our view of the hot and dense matter formed in central Au + Au collisions at √S NN = 200 GeV. These results suggest a large energy loss and flow of heavy quarks in the hot, dense matter. In recent years, the RHIC experiments upgraded the detectors; (1) PHENIX Collaboration installed silicon vertex tracker (VTX) at mid-rapidity region and forward silicon vertexmore » tracker (FVTX) at the forward rapidity region, and (2) STAR Collaboration installed the heavy flavor tracker (HFT) and the muon telescope detector (MTD) both at the mid-rapidity region. With these new upgrades, both experiments have collected large data samples. These new detectors enhance the capability of heavy flavor measurements via precision tracking. The PHENIX experiments established measurements of ψ(1S) and ψ(2S) production as a function of system size, p + p, p + Al, p + Au, and 3He + Au collisions at √S NN = 200 GeV. In p/ 3He + A collisions at forward rapidity, we observe no difference in the ψ(2S)/ψ(1S) ratio relative to p + p collisions. At backward rapidity, where the comoving particle density is higher, we find that the ψ(2S) is preferentially suppressed by a factor of two. STAR Collaboration presents the first J/ψ and Υ measurements in the di-muon decay channel in Au + Au collisions at GeV at mid-rapidity at RHIC. Here, we observe clear J/ψ RAA suppression and qualitatively well described by transport models simultaneously accounting for dissociation and regeneration processes.« less

  4. An on-line acoustic fluorocarbon coolant mixture analyzer for the ATLAS silicon tracker

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

    Bates, R.; Battistin, M.; Berry, S.

    2011-07-01

    The ATLAS silicon tracker community foresees an upgrade from the present octafluoro-propane (C{sub 3}F{sub 8}) evaporative cooling fluid - to a composite fluid with a probable 10-20% admixture of hexafluoro-ethane (C{sub 2}F{sub 6}). Such a fluid will allow a lower evaporation temperature and will afford the tracker silicon substrates a better safety margin against leakage current-induced thermal runaway caused by cumulative radiation damage as the luminosity profile at the CERN Large Hadron Collider increases. Central to the use of this new fluid is a new custom-developed speed-of-sound instrument for continuous real-time measurement of the C{sub 3}F{sub 8}/C{sub 2}F{sub 6} mixturemore » ratio and flow. An acoustic vapour mixture analyzer/flow meter with new custom electronics allowing ultrasonic frequency transmission through gas mixtures has been developed for this application. Synchronous with the emission of an ultrasound 'chirp' from an acoustic transmitter, a fast readout clock (40 MHz) is started. The clock is stopped on receipt of an above threshold sound pulse at the receiver. Sound is alternately transmitted parallel and anti-parallel with the vapour flow for volume flow measurement from transducers that can serve as acoustic transmitters or receivers. In the development version, continuous real-time measurement of C{sub 3}F{sub 8}/C{sub 2}F{sub 6} flow and calculation of the mixture ratio is performed within a graphical user interface developed in PVSS-II, the Supervisory, Control and Data Acquisition standard chosen for LHC and its experiments at CERN. The described instrument has numerous potential applications - including refrigerant leak detection, the analysis of hydrocarbons, vapour mixtures for semiconductor manufacture and anesthetic gas mixtures. (authors)« less

  5. An On-Line Acoustic Fluorocarbon Coolant Mixture Analyzer for the ATLAS Silicon Tracker

    NASA Astrophysics Data System (ADS)

    Bates, R.; Battistin, M.; Berry, S.; Bitadze, A.; Bonneau, P.; Bousson, N.; Boyd, G.; Botelho-Direito, J.; DiGirolamo, B.; Doubek, M.; Egorov, K.; Godlewski, J.; Hallewell, G.; Katunin, S.; Mathieu, M.; McMahon, S.; Nagai, K.; Perez-Rodriguez, E.; Rozanov, A.; Vacek, V.; Vitek, M.

    2012-10-01

    The ATLAS silicon tracker community foresees an upgrade from the present octafluoropropane (C3F8) evaporative cooling fluid to a composite fluid with a probable 10-20% admixture of hexafluoroethane (C2F6). Such a fluid will allow a lower evaporation temperature and will afford the tracker silicon substrates a better safety margin against leakage current-induced thermal runaway caused by cumulative radiation damage as the luminosity profile at the CERN Large Hadron Collider increases. Central to the use of this new fluid is a new custom-developed speed-of-sound instrument for continuous real-time measurement of the C3F8/C2F6 mixture ratio and flow. An acoustic vapour mixture analyzer/flow meter with new custom electronics allowing ultrasonic frequency transmission through gas mixtures has been developed for this application. Synchronous with the emission of an ultrasound `chirp' from an acoustic transmitter, a fast readout clock (40 MHz) is started. The clock is stopped on receipt of an above threshold sound pulse at the receiver. Sound is alternately transmitted parallel and anti-parallel with the vapour flow for volume flow measurement from transducers that can serve as acoustic transmitters or receivers. In the development version, continuous real-time measurement of C3F8/C2F6 flow and calculation of the mixture ratio is performed within a graphical user interface developed in PVSS-II, the Supervisory, Control and Data Acquisition standard chosen for LHC and its experiments at CERN. The described instrument has numerous potential applications - including refrigerant leak detection, the analysis of hydrocarbons, vapour mixtures for semi-conductor manufacture and anesthetic gas mixtures.

  6. How Accurate Is Your Activity Tracker? A Comparative Study of Step Counts in Low-Intensity Physical Activities.

    PubMed

    Alinia, Parastoo; Cain, Chris; Fallahzadeh, Ramin; Shahrokni, Armin; Cook, Diane; Ghasemzadeh, Hassan

    2017-08-11

    As commercially available activity trackers are being utilized in clinical trials, the research community remains uncertain about reliability of the trackers, particularly in studies that involve walking aids and low-intensity activities. While these trackers have been tested for reliability during walking and running activities, there has been limited research on validating them during low-intensity activities and walking with assistive tools. The aim of this study was to (1) determine the accuracy of 3 Fitbit devices (ie, Zip, One, and Flex) at different wearing positions (ie, pants pocket, chest, and wrist) during walking at 3 different speeds, 2.5, 5, and 8 km/h, performed by healthy adults on a treadmill; (2) determine the accuracy of the mentioned trackers worn at different sites during activities of daily living; and (3) examine whether intensity of physical activity (PA) impacts the choice of optimal wearing site of the tracker. We recruited 15 healthy young adults to perform 6 PAs while wearing 3 Fitbit devices (ie, Zip, One, and Flex) on their chest, pants pocket, and wrist. The activities include walking at 2.5, 5, and 8 km/h, pushing a shopping cart, walking with aid of a walker, and eating while sitting. We compared the number of steps counted by each tracker with gold standard numbers. We performed multiple statistical analyses to compute descriptive statistics (ie, ANOVA test), intraclass correlation coefficient (ICC), mean absolute error rate, and correlation by comparing the tracker-recorded data with that of the gold standard. All the 3 trackers demonstrated good-to-excellent (ICC>0.75) correlation with the gold standard step counts during treadmill experiments. The correlation was poor (ICC<0.60), and the error rate was significantly higher in walker experiment compared to other activities. There was no significant difference between the trackers and the gold standard in the shopping cart experiment. The wrist worn tracker, Flex, counted several steps when eating (P<.01). The chest tracker was identified as the most promising site to capture steps in more intense activities, while the wrist was the optimal wearing site in less intense activities. This feasibility study focused on 6 PAs and demonstrated that Fitbit trackers were most accurate when walking on a treadmill and least accurate during walking with a walking aid and for low-intensity activities. This may suggest excluding participants with assistive devices from studies that focus on PA interventions using commercially available trackers. This study also indicates that the wearing site of the tracker is an important factor impacting the accuracy performance. A larger scale study with a more diverse population, various activity tracker vendors, and a larger activity set are warranted to generalize our results. ©Parastoo Alinia, Chris Cain, Ramin Fallahzadeh, Armin Shahrokni, Diane Cook, Hassan Ghasemzadeh. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 11.08.2017.

  7. First Argon Gas Puff Experiments With 500 ns Implosion Time On Sphinx Driver

    NASA Astrophysics Data System (ADS)

    Zucchini, F.; Calamy, H.; Lassalle, F.; Loyen, A.; Maury, P.; Grunenwald, J.; Georges, A.; Morell, A.; Bedoch, J.-P.; Ritter, S.; Combes, P.; Smaniotto, O.; Lample, R.; Coleman, P. L.; Krishnan, M.

    2009-01-01

    Experiments have been performed at the SPHINX driver to study potential of an Argon Gas Puff load designed by AASC. We present here the gas Puff hardware and results of the last shot series. The Argon Gas Puff load used is injected thanks to a 20 cm diameter nozzle. The nozzle has two annuli and a central jet. The pressure and gas type in each of the nozzle plena can be independently adjusted to tailor the initial gaz density distribution. This latter is selected as to obtain an increasing radial density from outer shell towards the pinch axis in order to mitigate the RT instabilities and to increase radiating mass on axis. A flashboard unit produces a high intensity UV source to pre-ionize the Argon gas. Typical dimensions of the load are 200 mm in diameter and 40 mm height. Pressures are adjusted to obtain an implosion time around 550 ns with a peak current of 3.5 MA. With the goal of improving k-shell yield a mass scan of the central jet was performed and implosion time, mainly given by outer and middle plena settings, was kept constant. Tests were also done to reduce the implosion time for two configurations of the central jet. Strong zippering of the radiation production was observed mainly due to the divergence of the central jet over the 40 mm of the load height. Due to that feature k-shell radiation is mainly obtained near cathode. Therefore tests were done to mitigate this effect first by adjusting local pressure of middle and central jet and second by shortening the pinch length. At the end of this series, best shot gave 5 kJ of Ar k-shell yield. PCD detectors showed that k-shell x-ray power was 670 GW with a FWHM of less than 10 ns.

  8. Evidence for a Neoproterozoic carbonate ramp on the northern edge of the Central African craton: relations with late Proterozoic intracratonic troughs

    NASA Astrophysics Data System (ADS)

    Alvarez, Philippe

    1995-09-01

    During Late Proterozoic times, the Archaean Central African craton was affected by trough faulting which led to the formation of grabens, the Sangha aulacogen being the main structure of this type in the studied area. This transverse basin connects with other basins on the northern and south-western borders of the craton. During the Cryogenian, this network of basins was filled with fluvio-deltaic and lacustrine periglacial deposits. The glacio-eustatic transgression in Neoproterozoic III (end-Proterozoic) times flooded extensive areas of shelf on the northern edge of the craton, leading to the development of carbonate sedimentation in a broad outer shelf environment associated with nearshore barriers and evaporitic lagoons. These facies are similar to those developed in the West Congolian Schisto-calcaire (shale-limestone) ramp succession. The North-Central African ramp succession (sediment slope) contains an example of tidal rhythmites in vertical accretion, which occurs beneath the barrier deposits on the subtidal outer shelf. Mathematical analysis of the bedding pattern yields a period of 29 30 days for the lunar month, a result which is in agreement with astrophysical evidence for this epoch (i.e. 650 Ma ago). Major subsidence and seismic activity on this gently sloping platform, associated with the proximity of the Sangha aulacogen, caused the triggering of carbonate turbidites and mass flow deposits. The proliferation of microbial mats under euphotic conditions on an extensive shelf led to the build-up of a carbonate platform. During early Neoproterozoic III times, the West Congolian and North-Central African ramps prograded northwards and southwards, respectively, into the Sangha aulacogen. The sea at that time was restricted to a long graben-like basin, while a remaining area of marine sedimentation persisted into the Palaeozoic. Thus the pattern of end-Proterozoic carbonate sedimentation on the borders of the Central African craton can be interpreted in terms of an overall gently sloping ramp model with progradation converging towards the Sangha aulacogen.

  9. Evidence for a Neoproterozoic carbonate ramp on the northern edge of the Central African craton: relations with Late Proterozoic intracratonic troughs

    NASA Astrophysics Data System (ADS)

    Alvarez, Philippe

    During Late Proterozoic times, the Archaean Central African craton was affected by trough faulting which led to the formation of grabens, the Sangha aulacogen being the main structure of this type in the studied area. This transverse basin connects with other basins on the northern and south-western borders of the craton. During the Cryogenian, this network of basins was filled with fluvio-deltaic and lacustrine periglacial deposits. The glacio-eustatic transgression in Neoproterozoic III (end-Proterozoic) times flooded extensive areas of shelf on the northern edge of the craton, leading to the development of carbonate sedimentation in a broad outer shelf environment associated with nearshore barriers and evaporitic lagoons. These facies are similar to those developed in the West Congolian Schisto-calcaire (shale-limestone) ramp succession.The North-Central African ramp succession (sediment slope) contains an example of tidal rhythmites in vertical accretion, which occurs beneath the barrier deposits on the subtidal outer shelf. Mathematical analysis of the bedding pattern yields a period of 29-30 days for the lunar month, a result which is in agreement with astrophysical evidence for this epoch (i.e. 650Ma ago). Major subsidence and seismic activity on this gently sloping platform, associated with the proximity of the Sangha aulacogen, caused the triggering of carbonate turbidites and mass flow deposits. The proliferation of microbial mats under euphotic conditions on an extensive shelf led to the build-up of a carbonate platform. During early Neoproterozoic III times, the West Congolian and North-Central African ramps prograded northwards and southwards, respectively, into the Sangha aulacogen. The sea at that time was restricted to a long graben-like basin, while a remaining area of marine sedimentation persisted into the Palaeozoic. Thus the pattern of end-Proterozoic carbonate sedimentation on the borders of the Central African craton can be interpreted in terms of an overall gently sloping ramp model with progradation converging towards the Sangha aulacogen.

  10. An analysis of automatic human detection and tracking

    NASA Astrophysics Data System (ADS)

    Demuth, Philipe R.; Cosmo, Daniel L.; Ciarelli, Patrick M.

    2015-12-01

    This paper presents an automatic method to detect and follow people on video streams. This method uses two techniques to determine the initial position of the person at the beginning of the video file: one based on optical flow and the other one based on Histogram of Oriented Gradients (HOG). After defining the initial bounding box, tracking is done using four different trackers: Median Flow tracker, TLD tracker, Mean Shift tracker and a modified version of the Mean Shift tracker using HSV color space. The results of the methods presented in this paper are then compared at the end of the paper.

  11. A multi-hypothesis tracker for clicking whales.

    PubMed

    Baggenstoss, Paul M

    2015-05-01

    This paper describes a tracker specially designed to track clicking beaked whales using widely spaced bottom-mounted hydrophones, although it can be adapted to different species and sensors. The input to the tracker is a sequence of static localization solutions obtained using time difference of arrival information at widely spaced hydrophones. To effectively handle input localizations with high ambiguity, the tracker is based on multi-hypothesis tracker concepts, so it considers all potential association hypotheses and keeps a large number of potential tracks in memory. The method is demonstrated on actual data and shown to successfully track multiple beaked whales at depth.

  12. A Study of Supernova Remnants with Center-Filled X-Ray Morphology

    NASA Technical Reports Server (NTRS)

    Slane, Patrick O.

    1997-01-01

    CTA 1 is a center-filled supernova remnant (SNR) whose morphology and spectrum indicate the presence of a central pulsar, a synchrotron nebula, and a thermal component associated with the expansion of the blast wave into the interstellar medium. The centrally bright emission surrounds the position of a faint point source of x-rays observed with the ROSAT PSPC. Here we report on ASCA observations that confirm the nonthermal nature of the diffuse emission from the central regions of the remnant. We also present evidence for weak thermal emission that appears to increase in strength toward the outer boundary of the SNR. Thus, CTA 1 appears to be an x-ray composite remnant. Both the aftermath of the explosive supernova event and the energetic compact core are observable.

  13. Mitigating wildland fire hazard using complex network centrality measures

    NASA Astrophysics Data System (ADS)

    Russo, Lucia; Russo, Paola; Siettos, Constantinos I.

    2016-12-01

    We show how to distribute firebreaks in heterogeneous forest landscapes in the presence of strong wind using complex network centrality measures. The proposed framework is essentially a two-tire one: at the inner part a state-of- the-art Cellular Automata model is used to compute the weights of the underlying lattice network while at the outer part the allocation of the fire breaks is scheduled in terms of a hierarchy of centralities which influence the most the spread of fire. For illustration purposes we applied the proposed framework to a real-case wildfire that broke up in Spetses Island, Greece in 1990. We evaluate the scheme against the benchmark of random allocation of firebreaks under the weather conditions of the real incident i.e. in the presence of relatively strong winds.

  14. Large area directly heated lanthanum hexaboride cathode structure having predetermined emission profile

    DOEpatents

    Leung, Ka-Ngo; Gordon, Keith C.; Kippenham, Dean O.; Purgalis, Peter; Moussa, David; Williams, Malcom D.; Wilde, Stephen B.; West, Mark W.

    1989-01-01

    A large area directly heated lanthanum hexaboride (LaB.sub.6) cathode system (10) is disclosed. The system comprises a LaB.sub.6 cathode element (11) generally circular in shape about a central axis. The cathode element (11) has a head (21) with an upper substantially planar emission surface (23), and a lower downwardly and an intermediate body portion (26) which diminishes in cross-section from the head (21) towards the base (22) of the cathode element (11). A central rod (14) is connected to the base (22) of the cathode element (11) and extends along the central axis. Plural upstanding spring fingers (37) are urged against an outer peripheral contact surface (24) of the head end (21) to provide a mechanical and electrical connection to the cathode element (11).

  15. Training Surgical Residents With a Haptic Robotic Central Venous Catheterization Simulator.

    PubMed

    Pepley, David F; Gordon, Adam B; Yovanoff, Mary A; Mirkin, Katelin A; Miller, Scarlett R; Han, David C; Moore, Jason Z

    Ultrasound guided central venous catheterization (CVC) is a common surgical procedure with complication rates ranging from 5 to 21 percent. Training is typically performed using manikins that do not simulate anatomical variations such as obesity and abnormal vessel positioning. The goal of this study was to develop and validate the effectiveness of a new virtual reality and force haptic based simulation platform for CVC of the right internal jugular vein. A CVC simulation platform was developed using a haptic robotic arm, 3D position tracker, and computer visualization. The haptic robotic arm simulated needle insertion force that was based on cadaver experiments. The 3D position tracker was used as a mock ultrasound device with realistic visualization on a computer screen. Upon completion of a practice simulation, performance feedback is given to the user through a graphical user interface including scoring factors based on good CVC practice. The effectiveness of the system was evaluated by training 13 first year surgical residents using the virtual reality haptic based training system over a 3 month period. The participants' performance increased from 52% to 96% on the baseline training scenario, approaching the average score of an expert surgeon: 98%. This also resulted in improvement in positive CVC practices including a 61% decrease between final needle tip position and vein center, a decrease in mean insertion attempts from 1.92 to 1.23, and a 12% increase in time spent aspirating the syringe throughout the procedure. A virtual reality haptic robotic simulator for CVC was successfully developed. Surgical residents training on the simulation improved to near expert levels after three robotic training sessions. This suggests that this system could act as an effective training device for CVC. Copyright © 2017 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  16. The Colossal Cosmic Eye

    NASA Astrophysics Data System (ADS)

    2005-09-01

    Eighty-five million years ago on small planet Earth, dinosaurs ruled, ignorant of their soon-to-come demise in the great Jurassic extinction, while mammals were still small and shy creatures. The southern Andes of Bolivia, Chile, and Argentina were not yet formed and South America was still an island continent. Eighty-five million years ago, our Sun and its solar system was 60,000 light years away from where it now stands [1]. Eighty-five million years ago, in another corner of the Universe, light left the beautiful spiral galaxy NGC 1350, for a journey across the universe. Part of this light was recorded at the beginning of the year 2000 AD by ESO's Very Large Telescope, located on the 2,600m high Cerro Paranal in the Chilean Andes on planet Earth. Astronomers classify NGC 1350 as an Sa(r) type galaxy, meaning it is a spiral with large central regions. In fact, NGC 1350 lies at the border between the broken-ring spiral type and a grand design spiral with two major outer arms. It is about 130,000 light-years across and, hence, is slightly larger than our Milky Way. The rather faint and graceful outer arms originate at the inner main ring and can be traced for almost half a circle when they each meet the opposite arm, giving the impression of completing a second outer ring, the "eye". The arms are given a blue tint as a result of the presence of very young and massive stars. The amount of dust, seen as small fragmented dust spirals in the central part of the galaxy and producing a fine tapestry that bear resemblance with blood vessels in the eye, is also a signature of the formation of stars.

  17. The structure and function of the macula in patients with advanced retinitis pigmentosa.

    PubMed

    Vámos, Rita; Tátrai, Erika; Németh, János; Holder, Graham E; DeBuc, Delia Cabrera; Somfai, Gábor Márk

    2011-10-28

    To assess the structure and function of the macula in advanced retinitis pigmentosa (RP). Twenty-nine eyes of 22 patients with RP were compared against 17 control eyes. Time-domain optical coherence tomography (OCT) data were processed using OCTRIMA (optical coherence tomography retinal image analysis) as a means of quantifying commercial OCT system images. The thickness of the retinal nerve fiber layer (RNFL), ganglion cell layer and inner plexiform layer complex (GCL+IPL), inner nuclear layer and outer plexiform layer complex (INL+OPL), and the outer nuclear layer (ONL) were measured. Multifocal electroretinography (mfERG) was performed; two groups were formed based on the mfERG findings. Fourteen eyes had no detectable central retinal function (NCRF) on mfERG; detectable but abnormal retinal function (DRF) was present in the mfERG of the other 15 eyes. The thickness of the ONL in the central macular region was significantly less in the NCRF eyes compared with that in both DRF eyes and controls. The ONL was significantly thinner in the pericentral region in both patient groups compared with that in controls, whereas the thickness of the GCL+IPL and INL+OPL was significantly decreased only in the NCRF eyes. The RNFL in the peripheral region was significantly thicker, whereas the thickness of the GCL+IPL and ONL was significantly thinner in both patient groups compared with that in controls. The results are consistent with degeneration of the outer retina preceding inner retinal changes in RP. OCT image segmentation enables objective evaluation of retinal structural changes in RP, with potential use in the planning of therapeutic interventions and conceivably as an outcome measure.

  18. The Structure and Function of the Macula in Patients with Advanced Retinitis Pigmentosa

    PubMed Central

    Vámos, Rita; Tátrai, Erika; Németh, János; Holder, Graham E.; DeBuc, Delia Cabrera

    2011-01-01

    Purpose. To assess the structure and function of the macula in advanced retinitis pigmentosa (RP). Methods. Twenty-nine eyes of 22 patients with RP were compared against 17 control eyes. Time-domain optical coherence tomography (OCT) data were processed using OCTRIMA (optical coherence tomography retinal image analysis) as a means of quantifying commercial OCT system images. The thickness of the retinal nerve fiber layer (RNFL), ganglion cell layer and inner plexiform layer complex (GCL+IPL), inner nuclear layer and outer plexiform layer complex (INL+OPL), and the outer nuclear layer (ONL) were measured. Multifocal electroretinography (mfERG) was performed; two groups were formed based on the mfERG findings. Fourteen eyes had no detectable central retinal function (NCRF) on mfERG; detectable but abnormal retinal function (DRF) was present in the mfERG of the other 15 eyes. Results. The thickness of the ONL in the central macular region was significantly less in the NCRF eyes compared with that in both DRF eyes and controls. The ONL was significantly thinner in the pericentral region in both patient groups compared with that in controls, whereas the thickness of the GCL+IPL and INL+OPL was significantly decreased only in the NCRF eyes. The RNFL in the peripheral region was significantly thicker, whereas the thickness of the GCL+IPL and ONL was significantly thinner in both patient groups compared with that in controls. Conclusions. The results are consistent with degeneration of the outer retina preceding inner retinal changes in RP. OCT image segmentation enables objective evaluation of retinal structural changes in RP, with potential use in the planning of therapeutic interventions and conceivably as an outcome measure. PMID:21948552

  19. EVIDENCE FOR REDUCED SPECIFIC STAR FORMATION RATES IN THE CENTERS OF MASSIVE GALAXIES AT z  = 4

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

    Jung, Intae; Finkelstein, Steven L.; Song, Mimi

    2017-01-01

    We perform the first spatially resolved stellar population study of galaxies in the early universe ( z = 3.5–6.5), utilizing the Hubble Space Telescope Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey imaging data set over the GOODS-S field. We select a sample of 418 bright and extended galaxies at z  = 3.5–6.5 from a parent sample of ∼8000 photometric-redshift-selected galaxies from Finkelstein et al. We first examine galaxies at 3.5 ≲ z ≲ 4.0 using additional deep K -band survey data from the HAWK-I UDS and GOODS Survey which covers the 4000 Å break at these redshifts. We measure the stellar mass,more » star formation rate, and dust extinction for galaxy inner and outer regions via spatially resolved spectral energy distribution fitting based on a Markov Chain Monte Carlo algorithm. By comparing specific star formation rates (sSFRs) between inner and outer parts of the galaxies we find that the majority of galaxies with high central mass densities show evidence for a preferentially lower sSFR in their centers than in their outer regions, indicative of reduced sSFRs in their central regions. We also study galaxies at z ∼ 5 and 6 (here limited to high spatial resolution in the rest-frame ultraviolet only), finding that they show sSFRs which are generally independent of radial distance from the center of the galaxies. This indicates that stars are formed uniformly at all radii in massive galaxies at z  ∼ 5–6, contrary to massive galaxies at z ≲ 4.« less

  20. Evidence for Reduced Species Star Formation Rates in the Centers of Massive Galaxies at zeta = 4

    NASA Technical Reports Server (NTRS)

    Jung, Intae; Finkelstein, Steven L.; Song, Mimi; Dickinson, Mark; Dekel, Avishai; Ferguson, Henry C.; Fontana, Adriano; Koekemoer, Anton M.; Lu, Yu; Mobasher, Bahram; hide

    2017-01-01

    We perform the first spatially-resolved stellar population study of galaxies in the early universe z equals 3.5 -6.5, utilizing the Hubble Space Telescope Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) imaging dataset over the GOODS-S field. We select a sample of 418 bright and extended galaxies at z less than or approximately equal to 3.5-6.5 from a parent sample of approximately 8000 photometric-redshift selected galaxies from Finkelstein et al. We first examine galaxies at 3.5 less than or equal to z less than or approximately equal to 4.0 using additional deep K-band survey data from the HAWK-I UDS and GOODS Survey (HUGS) which covers the 4000 Angstrom break at these redshifts. We measure the stellar mass, star formation rate, and dust extinction for galaxy inner and outer regions via spatially-resolved spectral energy distribution fitting based on a Markov Chain Monte Carlo algorithm. By comparing specific star formation rates (sSFRs) between inner and outer parts of the galaxies we find that the majority of galaxies with the high central mass densities show evidence for a preferentially lower sSFR in their centers than in their outer regions, indicative of reduced sSFRs in their central regions. We also study galaxies at z approximately equal to 5 and 6 (here limited to high spatial resolution in the rest-frame ultraviolet only), finding that they show sSFRs which are generally independent of radial distance from the center of the galaxies. This indicates that stars are formed uniformly at all radii in massive galaxies at z approximately equal to 5-6, contrary tomassive galaxies at z. less than approximately equal to 4.

  1. Trap seal for open circuit liquid cooled turbines

    DOEpatents

    Grondahl, Clayton M.; Germain, Malcolm R.

    1980-01-01

    An improved trap seal for open circuit liquid cooled turbines is disclosed. The trap seal of the present invention includes an annular recess formed in the supply conduit of cooling channels formed in the airfoil of the turbine buckets. A cylindrical insert is located in the annular recesses and has a plurality of axial grooves formed along the outer periphery thereof and a central recess formed in one end thereof. The axial grooves and central recess formed in the cylindrical insert cooperate with the annular recess to define a plurality of S-shaped trap seals which permit the passage of liquid coolant but prohibit passage of gaseous coolant.

  2. Correlation tracking study for meter-class solar telescope on space shuttle. [solar granulation

    NASA Technical Reports Server (NTRS)

    Smithson, R. C.; Tarbell, T. D.

    1977-01-01

    The theory and expected performance level of correlation trackers used to control the pointing of a solar telescope in space using white light granulation as a target were studied. Three specific trackers were modeled and their performance levels predicted for telescopes of various apertures. The performance of the computer model trackers on computer enhanced granulation photographs was evaluated. Parametric equations for predicting tracker performance are presented.

  3. 77 FR 18260 - Outer Continental Shelf (OCS), Alaska OCS Region, Cook Inlet Planning Area, Proposed Oil and Gas...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-27

    ... OCS Region, Cook Inlet Planning Area, Proposed Oil and Gas Lease Sale 244 for OCS Oil and Gas Leasing...) identifies Sale 244 as a potential special interest sale for the Cook Inlet Planning Area in Alaska. While...-central region of the state, as evidenced by acreage leased in state sales and announced discoveries of...

  4. 77 FR 31037 - Outer Continental Shelf, Central and Western Gulf of Mexico Planning Areas, Oil and Gas Lease...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-24

    ... Western Gulf of Mexico Planning Areas, Oil and Gas Lease Sales for Years 2012-2017 (Sales 229, 227, 233... Register (76 FR 70748) correcting the sale numbers that were identified in the Call. This document... them with: 1. Whole blocks and portions of blocks deferred by the Gulf of Mexico Energy Security Act of...

  5. An Outbreak of Piscine Tuberculosis (Mycobacterosis) in an Aquarium,

    DTIC Science & Technology

    1987-06-11

    myositis . The other fish had several small foci of mineralization within renal tubules. After determining the cause of death of the 2 female guppies, we... Histopathological findings vary, but individual tubercles generally consist of an outer fibrous wall surrounding a central zone of epithelioid...fungal infection. Histopathologic examination was not performed. The 2 dwarf suckermouth catfish were added after the death of the parent guppy stock

  6. Low-Frequency Error Extraction and Compensation for Attitude Measurements from STECE Star Tracker.

    PubMed

    Lai, Yuwang; Gu, Defeng; Liu, Junhong; Li, Wenping; Yi, Dongyun

    2016-10-12

    The low frequency errors (LFE) of star trackers are the most penalizing errors for high-accuracy satellite attitude determination. Two test star trackers- have been mounted on the Space Technology Experiment and Climate Exploration (STECE) satellite, a small satellite mission developed by China. To extract and compensate the LFE of the attitude measurements for the two test star trackers, a new approach, called Fourier analysis, combined with the Vondrak filter method (FAVF) is proposed in this paper. Firstly, the LFE of the two test star trackers' attitude measurements are analyzed and extracted by the FAVF method. The remarkable orbital reproducibility features are found in both of the two test star trackers' attitude measurements. Then, by using the reproducibility feature of the LFE, the two star trackers' LFE patterns are estimated effectively. Finally, based on the actual LFE pattern results, this paper presents a new LFE compensation strategy. The validity and effectiveness of the proposed LFE compensation algorithm is demonstrated by the significant improvement in the consistency between the two test star trackers. The root mean square (RMS) of the relative Euler angle residuals are reduced from [27.95'', 25.14'', 82.43''], 3σ to [16.12'', 15.89'', 53.27''], 3σ.

  7. Searching for Lyman-alpha Emitters as a Probe of Cosmic Reionization and Peering Inside Galaxies in the First Two Billion Years

    NASA Astrophysics Data System (ADS)

    Jung, Intae; Finkelstein, Steven; CANDELS team

    2018-01-01

    In the reionization era an immediately accessible method for studying the intergalactic medium is to measure the equivalent width distribution of Lyman-alpha emission from galaxies with follow-up spectroscopy. To search for Lyman-alpha emission from galaxies at z ~ 5-8, we perform spectroscopic observations of candidate galaxies from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). We utilize data from the Keck DEIMOS (optical) and MOSFIRE (near-infrared) spectrographs, ensuring a comprehensive wavelength coverage of Lyman-alpha emission at z ~ 5-8. We have a total of 1170 object-hours of spectroscopic integration of galaxies at z > 5: 118 galaxies with DEIMOS and 69 galaxies with MOSFIRE. The equivalent width distribution of Lyman-alpha emission is constrained with the number of detected objects from our dataset by constructing detailed simulations of mock emission lines, which consider observational conditions and the photometric redshift probability distribution function. We present our robust measure of the evolution of the Lyman-alpha emission equivalent width distribution at z ~ 5-8.Understanding what drives star-formation quenching in the early universe is a long-standing puzzle. To reveal the hidden relation of quenching with galaxy structural properties, particularly central stellar mass density, we perform the first spatially resolved stellar population study of galaxies at z ~ 4, utilizing the CANDELS imaging data set over the GOODS-S field. We examine 166 photometric-redshift-selected galaxies at 3.5 < z < 4.0 with additional deep K-band survey data from the HAWK-I UDS and GOODS Survey which covers the 4000Å break at these redshifts. We estimate the stellar mass, star formation rate, and dust extinction for galaxy inner and outer regions via spatially resolved spectral energy distribution fitting based on a Markov Chain Monte Carlo algorithm. By comparing specific star formation rates (sSFRs) between inner and outer parts of the galaxies we find that the majority of galaxies with high central mass densities show evidence for a preferentially lower sSFR in their centers than in their outer regions, indicative of reduced sSFRs in their central regions.

  8. Childhood to adolescence: dust and gas clearing in protoplanetary disks

    NASA Astrophysics Data System (ADS)

    Brown, Joanna Margaret

    Disks are ubiquitous around young stars. Over time, disks dissipate, revealing planets that formed hidden by their natal dust. Since direct detection of young planets at small orbital radii is currently impossible, other tracers of planet formation must be found. One sign of disk evolution, potentially linked to planet formation, is the opening of a gap or inner hole in the disk. In this thesis, I have identified and characterized several cold disks with large inner gaps but retaining massive primordial outer disks. While cold disks are not common, with ~5% of disks showing signs of inner gaps, they provide proof that at least some disks evolve from the inside-out. These large gaps are equivalent to dust clearing from inside the Earth's orbit to Neptune's orbit or even the inner Kuiper belt. Unlike more evolved systems like our own, the central star is often still accreting and a large outer disk remains. I identified four cold disks in Spitzer 5-40 μm spectra and modeled these disks using a 2-D radiative transfer code to determine the gap properties. Outer gap radii of 20-45 AU were derived. However, spectrophotometric identification is indirect and model-dependent. To validate this interpretation, I observed three disks with a submillimeter interferometer and obtained the first direct images of the central holes. The images agree well with the gap sizes derived from the spectrophotometry. One system, LkH&alpha 330, has a very steep outer gap edge which seems more consistent with gravitational perturbation rather than gradual processes, such as grain growth and settling. Roughly 70% of cold disks show CO v=1&rarr 0 gas emission from the inner 1 AU and therefore are unlikely to have evolved due to photoevaporation. The derived rotation temperatures are significantly lower for the cold disks than disks without gaps. Unresolved (sub)millimeter photometry shows that cold disks have steeper colors, indicating that they are optically thin at these wavelengths, unlike their classical T Tauri star counterparts. The gaps are cleared of most ~100 μm sized grains as well as the ~10 μm sized grains visible in the mid-infrared as silicate emission features.

  9. Technology transfer: Imaging tracker to robotic controller

    NASA Technical Reports Server (NTRS)

    Otaguro, M. S.; Kesler, L. O.; Land, Ken; Erwin, Harry; Rhoades, Don

    1988-01-01

    The transformation of an imaging tracker to a robotic controller is described. A multimode tracker was developed for fire and forget missile systems. The tracker locks on to target images within an acquisition window using multiple image tracking algorithms to provide guidance commands to missile control systems. This basic tracker technology is used with the addition of a ranging algorithm based on sizing a cooperative target to perform autonomous guidance and control of a platform for an Advanced Development Project on automation and robotics. A ranging tracker is required to provide the positioning necessary for robotic control. A simple functional demonstration of the feasibility of this approach was performed and described. More realistic demonstrations are under way at NASA-JSC. In particular, this modified tracker, or robotic controller, will be used to autonomously guide the Man Maneuvering Unit (MMU) to targets such as disabled astronauts or tools as part of the EVA Retriever efforts. It will also be used to control the orbiter's Remote Manipulator Systems (RMS) in autonomous approach and positioning demonstrations. These efforts will also be discussed.

  10. Software and mathematical support of Kazakhstani star tracker

    NASA Astrophysics Data System (ADS)

    Akhmedov, D.; Yelubayev, S.; Ten, V.; Bopeyev, T.; Alipbayev, K.; Sukhenko, A.

    2016-10-01

    Currently the specialists of Kazakhstan have been developing the star tracker that is further planned to use on Kazakhstani satellites of various purposes. At the first stage it has been developed the experimental model of star tracker that has following characteristics: field of view 20°, update frequency 2 Hz, exclusion angle 40°, accuracy of attitude determination of optical axis/around optical axis 15/50 arcsec. Software and mathematical support are the most high technology parts of star tracker. The results of software and mathematical support development of experimental model of Kazakhstani star tracker are represented in this article. In particular, there are described the main mathematical models and algorithms that have been used as a basis for program units of preliminary image processing of starry sky, stars identification and star tracker attitude determination. The results of software and mathematical support testing with the help of program simulation complex using various configurations of defects including image sensor noises, point spread function modeling, optical system distortion up to 2% are presented. Analysis of testing results has shown that accuracy of attitude determination of star tracker is within the permissible range

  11. Breadboard stellar tracker system test report, volume 1

    NASA Technical Reports Server (NTRS)

    Kollodge, J. C.; Hubbard, M. W.; Jain, S.; Schons, C. A.

    1981-01-01

    The performance of a star tracker equipped with a focal plane detector was evaluated. The CID board is an array of 256 x 256 pixels which are 20 x 20 micrometers in dimension. The tracker used for test was a breadboard tracker system developed by BASD. Unique acquisition and tracking algorithms are employed to enhance performance. A pattern recognition process is used to test for proper image spread function and to avoid false acquisition on noise. A very linear, high gain, interpixel transfer function is derived for interpolating star position. The lens used in the tracker has an EFL of 100 mm. The tracker has an FOV of 2.93 degrees resulting in a pixel angular subtense of 41.253 arc sec in each axis. The test procedure used for the program presented a star to the tracker in a circular pattern of positions; the pattern was formed by projecting a simulated star through a rotatable deviation wedge. Further tests determined readout noise, Noise Equivalent Displacement during track, and spatial noise during acquisition by taking related data and reducing it.

  12. Optical System Error Analysis and Calibration Method of High-Accuracy Star Trackers

    PubMed Central

    Sun, Ting; Xing, Fei; You, Zheng

    2013-01-01

    The star tracker is a high-accuracy attitude measurement device widely used in spacecraft. Its performance depends largely on the precision of the optical system parameters. Therefore, the analysis of the optical system parameter errors and a precise calibration model are crucial to the accuracy of the star tracker. Research in this field is relatively lacking a systematic and universal analysis up to now. This paper proposes in detail an approach for the synthetic error analysis of the star tracker, without the complicated theoretical derivation. This approach can determine the error propagation relationship of the star tracker, and can build intuitively and systematically an error model. The analysis results can be used as a foundation and a guide for the optical design, calibration, and compensation of the star tracker. A calibration experiment is designed and conducted. Excellent calibration results are achieved based on the calibration model. To summarize, the error analysis approach and the calibration method are proved to be adequate and precise, and could provide an important guarantee for the design, manufacture, and measurement of high-accuracy star trackers. PMID:23567527

  13. Quantitative ionization chamber alignment to a water surface: Theory and simulation.

    PubMed

    Siebers, Jeffrey V; Ververs, James D; Tessier, Frédéric

    2017-07-01

    To examine the response properties of cylindrical cavity ionization chambers (ICs) in the depth-ionization buildup region so as to obtain a robust chamber-signal - based method for definitive water surface identification, hence absolute ionization chamber depth localization. An analytical model with simplistic physics and geometry is developed to explore the theoretical aspects of ionization chamber response near a phantom water surface. Monte Carlo simulations with full physics and ionization chamber geometry are utilized to extend the model's findings to realistic ion chambers in realistic beams and to study the effects of IC design parameters on the entrance dose response. Design parameters studied include full and simplified IC designs with varying central electrode thickness, wall thickness, and outer chamber radius. Piecewise continuous fits to the depth-ionization signal gradient are used to quantify potential deviation of the gradient discontinuity from the chamber outer radius. Exponential, power, and hyperbolic sine functional forms are used to model the gradient for chamber depths of zero to the depth of the gradient discontinuity. The depth-ionization gradient as a function of depth is maximized and discontinuous when a submerged IC's outer radius coincides with the water surface. We term this depth the gradient chamber alignment point (gCAP). The maximum deviation between the gCAP location and the chamber outer radius is 0.13 mm for a hypothetical 4 mm thick wall, 6.45 mm outer radius chamber using the power function fit, however, the chamber outer radius is within the 95% confidence interval of the gCAP determined by this fit. gCAP dependence on the chamber wall thickness is possible, but not at a clinically relevant level. The depth-ionization gradient has a discontinuity and is maximized when the outer-radius of a submerged IC coincides with the water surface. This feature can be used to auto-align ICs to the water surface at the time of scanning and/or be applied retrospectively to scan data to quantify absolute IC depth. Utilization of the gCAP should yield accurate and reproducible depth calibration for clinical depth-ionization measurements between setups and between users. © 2017 American Association of Physicists in Medicine.

  14. THE STRUCTURE AND CONCENTRATION OF SOLIDS IN PHOTORECEPTOR CELLS STUDIED BY REFRACTOMETRY AND INTERFERENCE MICROSCOPY

    PubMed Central

    Sidman, Richard L.

    1957-01-01

    Fragments of freshly obtained retinas of several vertebrate species were studied by refractometry, with reference to the structure of the rods and cones. The findings allowed a reassessment of previous descriptions based mainly on fixed material. The refractometric method was used also to measure the refractice indices and to calculate the concentrations of solids and water in the various cell segments. The main quantitative data were confirmed by interference microscopy. When examined by the method of refractometry the outer segments of freshly prepared retinal rods appear homogeneous. Within a few minutes a single eccentric longitudinal fiber appears, and transverse striations may develop. These changes are attributed to imbibition of water and swelling in structures normally too small for detection by light microscopy. The central "core" of outer segments and the chromophobic disc between outer and inner segments appear to be artifacts resulting from shrinkage during dehydration. The fresh outer segments of cones, and the inner segments of rods and cones also are described and illustrated. The volumes, refractive indices, concentrations of solids, and wet and dry weights of various segments of the photoreceptor cells were tabulated. Rod outer segments of the different species vary more than 100-fold in volume and mass but all have concentrations of solids of 40 to 43 per cent. Cone outer segments contain only about 30 per cent solids. The myoids, paraboloids, and ellipsoids of the inner segments likewise have characteristic refractive indices and concentrations of solids. Some of the limitations and particular virtues of refractometry as a method for quantitative analysis of living cells are discussed in comparison with more conventional biochemical techniques. Also the shapes and refractive indices of the various segments of photoreceptor cells are considered in relation to the absorption and transmission of light. The Stiles-Crawford effect can be accounted for on the basis of the structure of cone cells. PMID:13416308

  15. A protocol for evaluating video trackers under real-world conditions.

    PubMed

    Nawaz, Tahir; Cavallaro, Andrea

    2013-04-01

    The absence of a commonly adopted performance evaluation framework is hampering advances in the design of effective video trackers. In this paper, we present a single-score evaluation measure and a protocol to objectively compare trackers. The proposed measure evaluates tracking accuracy and failure, and combines them for both summative and formative performance assessment. The proposed protocol is composed of a set of trials that evaluate the robustness of trackers on a range of test scenarios representing several real-world conditions. The protocol is validated on a set of sequences with a diversity of targets (head, vehicle and person) and challenges (occlusions, background clutter, pose changes and scale changes) using six state-of-the-art trackers, highlighting their strengths and weaknesses on more than 187000 frames. The software implementing the protocol and the evaluation results are made available online and new results can be included, thus facilitating the comparison of trackers.

  16. Determinants for Sustained Use of an Activity Tracker: Observational Study

    PubMed Central

    Moons, Jonas; Kerkhof, Peter; Wiekens, Carina; De Groot, Martijn

    2017-01-01

    Background A lack of physical activity is considered to cause 6% of deaths globally. Feedback from wearables such as activity trackers has the potential to encourage daily physical activity. To date, little research is available on the natural development of adherence to activity trackers or on potential factors that predict which users manage to keep using their activity tracker during the first year (and thereby increasing the chance of healthy behavior change) and which users discontinue using their trackers after a short time. Objective The aim of this study was to identify the determinants for sustained use in the first year after purchase. Specifically, we look at the relative importance of demographic and socioeconomic, psychological, health-related, goal-related, technological, user experience–related, and social predictors of feedback device use. Furthermore, this study tests the effect of these predictors on physical activity. Methods A total of 711 participants from four urban areas in France received an activity tracker (Fitbit Zip) and gave permission to use their logged data. Participants filled out three Web-based questionnaires: at start, after 98 days, and after 232 days to measure the aforementioned determinants. Furthermore, for each participant, we collected activity data tracked by their Fitbit tracker for 320 days. We determined the relative importance of all included predictors by using Random Forest, a machine learning analysis technique. Results The data showed a slow exponential decay in Fitbit use, with 73.9% (526/711) of participants still tracking after 100 days and 16.0% (114/711) of participants tracking after 320 days. On average, participants used the tracker for 129 days. Most important reasons to quit tracking were technical issues such as empty batteries and broken trackers or lost trackers (21.5% of all Q3 respondents, 130/601). Random Forest analysis of predictors revealed that the most influential determinants were age, user experience–related factors, mobile phone type, household type, perceived effect of the Fitbit tracker, and goal-related factors. We explore the role of those predictors that show meaningful differences in the number of days the tracker was worn. Conclusions This study offers an overview of the natural development of the use of an activity tracker, as well as the relative importance of a range of determinants from literature. Decay is exponential but slower than may be expected from existing literature. Many factors have a small contribution to sustained use. The most important determinants are technical condition, age, user experience, and goal-related factors. This finding suggests that activity tracking is potentially beneficial for a broad range of target groups, but more attention should be paid to technical and user experience–related aspects of activity trackers. PMID:29084709

  17. Ring faults and ring dikes around the Orientale basin on the Moon.

    PubMed

    Andrews-Hanna, Jeffrey C; Head, James W; Johnson, Brandon; Keane, James T; Kiefer, Walter S; McGovern, Patrick J; Neumann, Gregory A; Wieczorek, Mark A; Zuber, Maria T

    2018-08-01

    The Orientale basin is the youngest and best-preserved multiring impact basin on the Moon, having experienced only modest modification by subsequent impacts and volcanism. Orientale is often treated as the type example of a multiring basin, with three prominent rings outside of the inner depression: the Inner Rook Montes, the Outer Rook Montes, and the Cordillera. Here we use gravity data from NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission to reveal the subsurface structure of Orientale and its ring system. Gradients of the gravity data reveal a continuous ring dike intruded into the Outer Rook along the plane of the fault associated with the ring scarp. The volume of this ring dike is ~18 times greater than the volume of all extrusive mare deposits associated with the basin. The gravity gradient signature of the Cordillera ring indicates an offset along the fault across a shallow density interface, interpreted to be the base of the low-density ejecta blanket. Both gravity gradients and crustal thickness models indicate that the edge of the central cavity is shifted inward relative to the equivalent Inner Rook ring at the surface. Models of the deep basin structure show inflections along the crust-mantle interface at both the Outer Rook and Cordillera rings, indicating that the basin ring faults extend from the surface to at least the base of the crust. Fault dips range from 13-22° for the Cordillera fault in the northeastern quadrant, to 90° for the Outer Rook in the northwestern quadrant. The fault dips for both outer rings are lowest in the northeast, possibly due to the effects of either the direction of projectile motion or regional gradients in pre-impact crustal thickness. Similar ring dikes and ring faults are observed around the majority of lunar basins.

  18. Imaging Shock Fronts in the Outer Ejecta of Eta Carinae

    NASA Astrophysics Data System (ADS)

    Smith, Nathan

    2017-08-01

    Although Eta Car has been imaged many times with HST to monitor the central star and the bright Homunculus Nebula, we propose the first WFC3 imaging of Eta Car to study the more extended Outer Ejecta from previous eruptions. WFC3 has two key filters that have not been used before to image Eta Car, which will provide critical physical information about its eruptive history: (1) F280N with WFC3/UVIS will produce the first Mg II 2800 image of Eta Car, the sharpest image of its complex Outer Ejecta, and will unambiguously trace shock fronts, and (2) F126N with WFC3/IR will sample [Fe II] 12567 arising in the densest post-shock gas. Eta Car is surrounded by a bright, soft X-ray shell seen in Chandra images, which arises from the fastest 1840s ejecta overtaking slower older material. Our recent proper motion measurements show that the outer knots were ejected in two outbursts several hundred years before the 1840s eruption, and spectroscopy of light echoes has recently revealed extremely fast ejecta during the 1840s that indicate an explosive event. Were those previous eruptions explosive as well? If so, were they as energetic, did they also have such fast ejecta, and did they have the same geometry? The structure and excitation of the Outer Ejecta hold unique clues for reconstructing Eta Car's violent mass loss history. The locations of shock fronts in circumstellar material provide critical information, because they identify past discontinuities in the mass loss. This is one of the only ways to investigate the long term (i.e. centuries) evolution and duty cycle of eruptive mass loss in the most massive stars.

  19. Temporal dynamics of stem expansion and contraction in savanna trees: withdrawal and recharge of stored water.

    PubMed

    Scholz, Fabian C; Bucci, Sandra J; Goldstein, Guillermo; Meinzer, Frederick C; Franco, Augusto C; Miralles-Wilhelm, Fernando

    2008-03-01

    Relationships between diel changes in stem expansion and contraction and discharge and refilling of stem water storage tissues were studied in six dominant Neotropical savanna (cerrado) tree species from central Brazil. Two stem tissues were studied, the active xylem or sapwood and the living tissues located between the cambium and the cork, made up predominantly of parenchyma cells (outer parenchyma). Outer parenchyma and sapwood density ranged from 320 to 410 kg m(-3) and from 420 to 620 kg m(-3), respectively, depending on the species. The denser sapwood tissues exhibited smaller relative changes in cross-sectional area per unit change in water potential compared with the outer parenchyma. Despite undergoing smaller relative changes in cross-sectional area, the sapwood released about 3.5 times as much stored water for a given change in area as the outer parenchyma. Cross-sectional area decreased earlier in the morning in the outer parenchyma than in the sapwood with lag times up to 30 min for most species. The relatively small lag time between dimensional changes of the two tissues suggested that they were hydraulically well connected. The initial morning increase in basal sap flow lagged about 10 to 130 min behind that of branch sap flow. Species-specific lag times between morning declines in branch and main stem cross-sectional area were a function of relative stem water storage capacity, which ranged from 16 to 31% of total diurnal water loss. Reliance on stored water to temporarily replace transpirational losses is one of the homeostatic mechanisms that constrain the magnitude of leaf water deficits in cerrado trees.

  20. Biogenesis of the mitochondrial TOM complex: Mim1 promotes insertion and assembly of signal-anchored receptors.

    PubMed

    Becker, Thomas; Pfannschmidt, Sylvia; Guiard, Bernard; Stojanovski, Diana; Milenkovic, Dusanka; Kutik, Stephan; Pfanner, Nikolaus; Meisinger, Chris; Wiedemann, Nils

    2008-01-04

    The translocase of the outer membrane (TOM complex) is the central entry gate for nuclear-encoded mitochondrial precursor proteins. All Tom proteins are also encoded by nuclear genes and synthesized as precursors in the cytosol. The channel-forming beta-barrel protein Tom40 is targeted to mitochondria via Tom receptors and inserted into the outer membrane by the sorting and assembly machinery (SAM complex). A further outer membrane protein, Mim1, plays a less defined role in assembly of Tom40 into the TOM complex. The three receptors Tom20, Tom22, and Tom70 are anchored in the outer membrane by a single transmembrane alpha-helix, located at the N terminus in the case of Tom20 and Tom70 (signal-anchored) or in the C-terminal portion in the case of Tom22 (tail-anchored). Insertion of the precursor of Tom22 into the outer membrane requires pre-existing Tom receptors while the import pathway of the precursors of Tom20 and Tom70 is only poorly understood. We report that Mim1 is required for efficient membrane insertion and assembly of Tom20 and Tom70, but not Tom22. We show that Mim1 associates with SAM(core) components to a large SAM complex, explaining its role in late steps of the assembly pathway of Tom40. We conclude that Mim1 is not only required for biogenesis of the beta-barrel protein Tom40 but also for membrane insertion and assembly of signal-anchored Tom receptors. Thus, Mim1 plays an important role in the efficient assembly of the mitochondrial TOM complex.

  1. Optical Alignment of the Global Precipitation Measurement (GPM) Star Trackers

    NASA Technical Reports Server (NTRS)

    Hetherington, Samuel; Osgood, Dean; McMann, Joe; Roberts, Viki; Gill, James; Mclean, Kyle

    2013-01-01

    The optical alignment of the star trackers on the Global Precipitation Measurement (GPM) core spacecraft at NASA Goddard Space Flight Center (GSFC) was challenging due to the layout and structural design of the GPM Lower Bus Structure (LBS) in which the star trackers are mounted as well as the presence of the star tracker shades that blocked line-of-sight to the primary star tracker optical references. The initial solution was to negotiate minor changes in the original LBS design to allow for the installation of a removable item of ground support equipment (GSE) that could be installed whenever measurements of the star tracker optical references were needed. However, this GSE could only be used to measure secondary optical reference cube faces not used by the star tracker vendor to obtain the relationship information and matrix transformations necessary to determine star tracker alignment. Unfortunately, due to unexpectedly large orthogonality errors between the measured secondary adjacent cube faces and the lack of cube calibration data, we required a method that could be used to measure the same reference cube faces as originally measured by the vendor. We describe an alternative technique to theodolite auto-collimation for measurement of an optical reference mirror pointing direction when normal incidence measurements are not possible. This technique was used to successfully align the GPM star trackers and has been used on a number of other NASA flight projects. We also discuss alignment theory as well as a GSFC-developed theodolite data analysis package used to analyze angular metrology data.

  2. Elliptically framed tip-tilt mirror optimized for stellar tracking

    NASA Astrophysics Data System (ADS)

    Clark, James H.; Penado, F. E.; Petak, Jeremy

    2015-09-01

    We compare a design innovation of an elliptically framed tip-tilt optical tracker with an existing circularly framed tracker for the Navy Precision Optical Interferometer. The tracker stabilizes a 12.5 cm stellar beam on a target hundreds of meters away and requires an increase in operational frequency. We reduced mass and size by integrating an elliptical mirror as one of the rotating components, which eliminated a rotating frame. We used the same materials as the existing tracker; however, light-weighted both the aluminum frame and Zerodur® mirror. We generated a computer-aided design model, converted it into a finite element model and performed modal analysis on two load cases. In load case 1, we tied down three points on the bottom surface of the tracker corresponding to the tie-down points of the comparison tracker. This reveals a first mode (lowest) frequency of 140 Hz, a factor of two over the baseline tracker's first mode frequency of 67 Hz. In load case 2, we constrained four additional points inboard of the corners of the tracker base, for a total of seven tie-downs, simulating a firmly bolted and secured mount. The first mode of vibration for this case is 211 Hz, an increase over load case 1 by a factor of 1.5 and more than three times the fundamental frequency of the existing tracker. We conclude that these geometrical changes with the additional tie-down bolts are a viable solution path forward to improve steering speed and recommend a continuation with this effort.

  3. Validity, reliability and feasibility of commercially available activity trackers in physical therapy for people with a chronic disease: a study protocol of a mixed methods research.

    PubMed

    Beekman, Emmylou; Braun, Susy M; Ummels, Darcy; van Vijven, Kim; Moser, Albine; Beurskens, Anna J

    2017-01-01

    For older people and people with a chronic disease, physical activity provides health benefits. Patients and healthcare professionals can use commercially available activity trackers to objectively monitor (alterations in) activity levels and patterns and to support physical activity. However, insight in the validity, reliability, and feasibility of these trackers in people with a chronic disease is needed. In this article, a study protocol is described in which the validity, reliability (part A), and feasibility from a patient and therapist's point of view (part B) of commercially available activity trackers in daily life and health care is investigated. In part A, a quantitative cross-sectional study, an activity protocol that simulates everyday life activities will be used to determine the validity and reliability of nine commercially available activity trackers. Video recordings will act as the gold standard. In part B, a qualitative participatory action research study will be performed to gain insight in the use of activity trackers in peoples' daily life and therapy settings. Objective feasibility of the activity trackers will be measured with questionnaires, and subjective feasibility (experiences) will be explored in a community of practice. Physical therapists ( n  = 8) will regularly meet during 6 months to learn from each other regarding the actual use of activity trackers in therapy. Therapists and patients ( n  = 48) will decide together which tracker will be used in therapy and for which purpose (e.g., monitoring, goal setting). Data from the therapist' and patients' experiences will be collected by interviews (individual and focus groups) and analyzed by a directed content analysis. At the time of submission, selection of activity trackers, development of the activity protocol, and the ethical approval process are finished. Data collection and data processing are ongoing. The relevance of the study as well as the advantages and disadvantages of several aspects of the chosen design are discussed. The results acquired from both study parts can be used to create decision aids that may assist therapists and people with a chronic disease in choosing a suitable activity tracker, and to facilitate use of these activity trackers in health care settings. Ethical approval has been obtained from two medical-ethical committees (nr. 15-N-109, 15-N-48 and MEC-15-07).

  4. Grumman S2F-1 Tracker at NACA Lewis

    NASA Image and Video Library

    1956-08-21

    The NACA’s Lewis Flight Propulsion Laboratory acquired the Grumman S2F-1 Tracker from the Navy in 1955 to study icing instrumentation. Lewis’s icing research program was winding down at the time. The use of jet engines was increasing thus reducing the threat of ice accumulation. Nonetheless Lewis continued research on the instrumentation used to detect icing conditions. The S2F-1 Tracker was a carrier-based submarine hunter for the Navy. Grumman developed the Tracker as a successor to its Korean War-era Guardian patrol aircraft. Prototypes first flew in late 1952 and battle-ready versions entered Naval service in early 1954. The Navy utilized the Trackers to protect fleets from attack.

  5. Turbine nozzle positioning system

    DOEpatents

    Norton, Paul F.; Shaffer, James E.

    1996-01-30

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

  6. Turbine nozzle positioning system

    DOEpatents

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

    1996-01-30

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

  7. Prestin modulates mechanics and electromechanical force of the plasma membrane.

    PubMed

    Zhang, Rui; Qian, Feng; Rajagopalan, Lavanya; Pereira, Fred A; Brownell, William E; Anvari, Bahman

    2007-07-01

    The voltage-dependent movement, or electromotility, of cochlear outer hair cells contributes to cochlear amplification in mammalian hearing. Outer hair-cell electromotility involves a membrane-based motor in which the membrane protein prestin plays a central role. We have investigated the contribution of prestin to the mechanics and electromechanical force (EMF) generation of the membrane using membrane tethers formed from human embryonic kidney (HEK) cells. Several measures of membrane tether mechanics are greater in tethers pulled from HEK cells transfected with prestin when compared to control untransfected HEK cells. A single point mutation of alanine to tryptophan (A100W) in prestin eliminates prestin-associated charge movement and diminishes EMF but does not alter passive membrane mechanics. These results suggest that prestin-associated charge transfer is necessary for maximal EMF generation by the membrane.

  8. Prestin Modulates Mechanics and Electromechanical Force of the Plasma Membrane

    PubMed Central

    Zhang, Rui; Qian, Feng; Rajagopalan, Lavanya; Pereira, Fred A.; Brownell, William E.; Anvari, Bahman

    2007-01-01

    The voltage-dependent movement, or electromotility, of cochlear outer hair cells contributes to cochlear amplification in mammalian hearing. Outer hair-cell electromotility involves a membrane-based motor in which the membrane protein prestin plays a central role. We have investigated the contribution of prestin to the mechanics and electromechanical force (EMF) generation of the membrane using membrane tethers formed from human embryonic kidney (HEK) cells. Several measures of membrane tether mechanics are greater in tethers pulled from HEK cells transfected with prestin when compared to control untransfected HEK cells. A single point mutation of alanine to tryptophan (A100W) in prestin eliminates prestin-associated charge movement and diminishes EMF but does not alter passive membrane mechanics. These results suggest that prestin-associated charge transfer is necessary for maximal EMF generation by the membrane. PMID:17468166

  9. Electrostatic generator/motor having rotors of varying thickness and a central stator electrically connected together into two groups

    DOEpatents

    Post, Richard F.

    2010-11-16

    A sub-module consists of a set of two outer sets of stationary fan-blade-shaped sectors. These outer sectors include conductive material and are maintained at ground potential in several examples. Located midway between them is a set of stationary sector plates with each plate being electrically insulated from the others. An example provides that the inner sector plates are connected together alternately, forming two groups of parallel-connected condensers that are then separately connected, through high charging circuit resistances, to a source of DC potential with respect to ground, with an additional connecting lead being provided for each group to connect their output as an AC output to a load. These same leads can he used, when connected to a driver circuit, to produce motor action.

  10. The structure of the β-barrel assembly machinery complex

    DOE PAGES

    Bakelar, Jeremy; Buchanan, Susan K.; Noinaj, Nicholas

    2016-01-08

    β-Barrel outer membrane proteins (OMPs) are found in the outer membranes of Gram-negative bacteria and are essential for nutrient import, signaling, and adhesion. A 200-kilodalton five-component complex called the β-barrel assembly machinery (BAM) complex has been implicated in the biogenesis of OMPs. In this paper, we report the structure of the BAM complex from Escherichia coli, revealing that binding of BamCDE modulates the conformation of BamA, the central component, which may serve to regulate the BAM complex. The periplasmic domain of BamA was in a closed state that prevents access to the barrel lumen, which indicates substrate OMPs may notmore » be threaded through the barrel during biogenesis. Finally and further, conformational shifts in the barrel domain lead to opening of the exit pore and rearrangement at the lateral gate.« less

  11. The structure of the β-barrel assembly machinery complex

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

    Bakelar, Jeremy; Buchanan, Susan K.; Noinaj, Nicholas

    β-Barrel outer membrane proteins (OMPs) are found in the outer membranes of Gram-negative bacteria and are essential for nutrient import, signaling, and adhesion. A 200-kilodalton five-component complex called the β-barrel assembly machinery (BAM) complex has been implicated in the biogenesis of OMPs. In this paper, we report the structure of the BAM complex from Escherichia coli, revealing that binding of BamCDE modulates the conformation of BamA, the central component, which may serve to regulate the BAM complex. The periplasmic domain of BamA was in a closed state that prevents access to the barrel lumen, which indicates substrate OMPs may notmore » be threaded through the barrel during biogenesis. Finally and further, conformational shifts in the barrel domain lead to opening of the exit pore and rearrangement at the lateral gate.« less

  12. Optical fiber cable chemical stripping fixture

    NASA Technical Reports Server (NTRS)

    Kolasinski, John R. (Inventor); Coleman, Alexander M. (Inventor)

    1995-01-01

    An elongated fixture handle member is connected to a fixture body member with both members having interconnecting longitudinal central axial bores for the passage of an optical cable therethrough. The axial bore of the fixture body member, however, terminates in a shoulder stop for the outer end of a jacket of the optical cable covering both an optical fiber and a coating therefor, with an axial bore of reduced diameter continuing from the shoulder stop forward for a predetermined desired length to the outer end of the fixture body member. A subsequent insertion of the fixture body member including the above optical fiber elements into a chemical stripping solution results in a softening of the exposed external coating thereat which permits easy removal thereof from the optical fiber while leaving a desired length coated fiber intact within the fixture body member.

  13. Geometric Model for Tracker-Target Look Angles and Line of Slight Distance

    DTIC Science & Technology

    2015-10-20

    412TW-PA-15239 Geometric Model for Tracker -Target Look Angles and Line of Slight Distance DANIEL T. LAIRD AIR FORCE TEST CENTER EDWARDS...15 – 23 OCT 15 4. TITLE AND SUBTITLE Geometric Model for Tracker -Target Look Angles and Line of Slight Distance 5a. CONTRACT...include area code) 661-277-8615 Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18 GEOMETRIC MODEL FOR TRACKER -TARGET LOOK ANGLES

  14. Integration of an Apple II Plus Computer into an Existing Dual Axis Sun Tracker System.

    DTIC Science & Technology

    1984-06-01

    Identify by block number) S, tpec l Sun Tracker System Solar Energy Apple II Plus Computer 20. ABSTRACT (’ ntlnue on reveree ide If neceesery end...14 4. Dual Axis Sun Tracker (Side View) ----------------- 15 5. Solar Tracker System Block Diagram ---------------- 17 6. Plug Wiring Diagram for Top...sources will be competitive. Already many homes have solar collectors and other devices designed to decrease the consumption of gas, oil, and

  15. A Deep Chandra Observation of the Centaurus Cluster:Bubbles, Filaments and Edges

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

    Fabian, A.C.

    2005-03-14

    X-ray images and gas temperatures taken from a deep {approx}200 ks Chandra observation of the Centaurus cluster are presented. Multiple inner bubbles and outer semicircular edges are revealed, together with wispy filaments of soft X-ray emitting gas. The frothy central structure and eastern edge are likely due to the central radio source blowing bubbles in the intracluster gas. The semicircular edges to the surface brightness maps 32 kpc to the east and 17.5 kpc to the west are marked by sharp temperature increases and abundance drops. The edges could be due to sloshing motions of the central potential, or aremore » possibly enhanced by earlier radio activity. The high abundance of the innermost gas (about 2.5 times Solar) limits the amount of diffusion and mixing taking place.« less

  16. A Newly Discovered Supernova Remnant and MSH 11-62 and 3C58

    NASA Technical Reports Server (NTRS)

    Slane, Patrick O.

    2000-01-01

    CTA 1 is a center-filled supernova remnant (SNR) whose morphology and spectrum indicate the presence of a central pulsar, a synchrotron nebula, and a thermal component associated with the expansion of the blast wave into the interstellar medium. The centrally bright emission surrounds the position of a faint point source of X-rays observed with the ROSAT Position Sensitive Proportional Counter (PSPC). Here we report on Advanced Spacecraft for Cosmology Astrophysics (ASCA) observations that confirm the nonthermal nature of the diffuse emission from the central regions of the remnant. We also present evidence for weak thermal emission that appears to increase in strength toward the outer boundary of the SNR. Thus, CTA 1 appears to be an X-ray composite remnant. Both the aftermath of the explosive supernova event and the energetic compact core are observable.

  17. Silicon pixel-detector R&D for CLIC

    NASA Astrophysics Data System (ADS)

    Nürnberg, A.

    2016-11-01

    The physics aims at the future CLIC high-energy linear e+e- collider set very high precision requirements on the performance of the vertex and tracking detectors. Moreover, these detectors have to be well adapted to the experimental conditions, such as the time structure of the collisions and the presence of beam-induced backgrounds. The principal challenges are: a point resolution of a few μm, ultra-low mass (~ 0.2%X0 per layer for the vertex region and ~ 1%X0 per layer for the outer tracker), very low power dissipation (compatible with air-flow cooling in the inner vertex region) and pulsed power operation, complemented with ~ 10 ns time stamping capabilities. A highly granular all-silicon vertex and tracking detector system is under development, following an integrated approach addressing simultaneously the physics requirements and engineering constraints. For the vertex-detector region, hybrid pixel detectors with small pitch (25 μm) and analog readout are explored. For the outer tracking region, both hybrid concepts and fully integrated CMOS sensors are under consideration. The feasibility of ultra-thin sensor layers is validated with Timepix3 readout ASICs bump bonded to active edge planar sensors with 50 μm to 150 μm thickness. Prototypes of CLICpix readout ASICs implemented in 6525 nm CMOS technology with 25 μm pixel pitch have been produced. Hybridisation concepts have been developed for interconnecting these chips either through capacitive coupling to active HV-CMOS sensors or through bump-bonding to planar sensors. Recent R&D achievements include results from beam tests with all types of hybrid assemblies. Simulations based on Geant4 and TCAD are used to validate the experimental results and to assess and optimise the performance of various detector designs.

  18. Counting Steps in Activities of Daily Living in People With a Chronic Disease Using Nine Commercially Available Fitness Trackers: Cross-Sectional Validity Study.

    PubMed

    Ummels, Darcy; Beekman, Emmylou; Theunissen, Kyra; Braun, Susy; Beurskens, Anna J

    2018-04-02

    Measuring physical activity with commercially available activity trackers is gaining popularity. People with a chronic disease can especially benefit from knowledge about their physical activity pattern in everyday life since sufficient physical activity can contribute to wellbeing and quality of life. However, no validity data are available for this population during activities of daily living. The aim of this study was to investigate the validity of 9 commercially available activity trackers for measuring step count during activities of daily living in people with a chronic disease receiving physiotherapy. The selected activity trackers were Accupedo (Corusen LLC), Activ8 (Remedy Distribution Ltd), Digi-Walker CW-700 (Yamax), Fitbit Flex (Fitbit inc), Lumoback (Lumo Bodytech), Moves (ProtoGeo Oy), Fitbit One (Fitbit inc), UP24 (Jawbone), and Walking Style X (Omron Healthcare Europe BV). In total, 130 persons with chronic diseases performed standardized activity protocols based on activities of daily living that were recorded on video camera and analyzed for step count (gold standard). The validity of the trackers' step count was assessed by correlation coefficients, t tests, scatterplots, and Bland-Altman plots. The correlations between the number of steps counted by the activity trackers and the gold standard were low (range: -.02 to .33). For all activity trackers except for Fitbit One, a significant systematic difference with the gold standard was found for step count. Plots showed a wide range in scores for all activity trackers; Activ8 showed an average overestimation and the other 8 trackers showed underestimations. This study showed that the validity of 9 commercially available activity trackers is low measuring steps while individuals with chronic diseases receiving physiotherapy engage in activities of daily living. ©Darcy Ummels, Emmylou Beekman, Kyra Theunissen, Susy Braun, Anna J Beurskens. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 02.04.2018.

  19. Novel self-powered pH indicator using ionic polymeric gel muscles

    NASA Astrophysics Data System (ADS)

    Shahinpoor, Mohsen

    1994-05-01

    A novel design for a torsional spring-loaded pH indicator using ionic polymeric gel fibrous muscles is presented. The essential parts of the proposed self-powered pH indicator are a pair of co-axial and concentric cylinders, an assembly of fibrous polyacrylonitrile (PAN) muscles, a torsional spring, and a dial indicator. The two co-axial cylinders are such that the inner cylinder may pivotally rotate about the central rotation axis that is fixed to the inner bottom or side of the outer cylinder. The outer cylinder also serves as a reservoir for any liquid whose pH is to be determined either statically or dynamically. The internal cylindrical drum is further equipped with a dial indicator on one of its outer end caps such that when a pH environment is present the contraction or expansion of the PAN fibers cause the inner drum to rotate and thus give a reading of the dial indicator. The motion of the dial indicator may also be converted to an electrical signal (voltage) for digital electronics display and computer control. A mathematical model is also presented for the dynamic response of the self-powered pH indicator made with contractile PAN fiber bundle assemblies.

  20. Crystal structure of (E)-1-[4-({4-[(4-meth­oxy­benzyl­idene)amino]­phen­yl}sulfan­yl)phen­yl]ethan-1-one

    PubMed Central

    Hebbachi, Rabihe; Djedouani, Amel; Kadri, Soumia; Mousser, Hénia; Mousser, Abdelhamid

    2015-01-01

    The title Schiff base compound, C22H19NO2S, crystallized with two independent mol­ecules (A and B) in the asymmetric unit. Both mol­ecules have an E conformation about the C=N bond. The two mol­ecules differ in the orientation of the aromatic rings with respect to each other. The outer 4-meth­oxy­benzene ring is inclined to the central benzene ring and the outer 4-acetyl­benzene ring by 1.80 (19) and 63.73 (19)°, respectively, in mol­ecule A, and by 6.72 (18) and 68.53 (19)°, respectively, in mol­ecule B. The two outer benzene rings are inclined to one another by 63.77 (18) and 63.19 (18)° in mol­ecules A and B, respectively. In the crystal, the individual mol­ecules stack in columns along [010], and are linked by a number of C—H⋯π inter­actions, forming slabs lying parallel to (001). PMID:25878856

  1. Phenologically distinct phytoplankton regions on the Faroe Shelf - identified by satellite data, in-situ observations and model

    NASA Astrophysics Data System (ADS)

    Eliasen, Sólvá Káradóttir; Hátún, Hjálmar; Larsen, Karin Margretha H.; Hansen, Bogi; Rasmussen, Till Andreas S.

    2017-05-01

    Marked inter-annual fluctuations in the primary production on the Faroe shelf propagate to higher trophic levels and influence commercial fish stocks. This has previously been demonstrated based on weekly chlorophyll samples from a coastal station, dating back to 1997. However, the spatial extent, for which the coastal samples are representative, has not been well defined, and potential bio-geographical segregations of the shelf have not been considered. By integrating 18 years of chlorophyll satellite data, supplemented by in-situ, model, and meteorological reanalysis data, we identify three regions with unique characteristics with regards to surface chlorophyll and vertical structure - the Central Shelf, the Outer Shelf and the Eastern Banks. The observed difference in timing of the spring bloom in these regions helps explain different spawning patterns of important fish stocks, and the spatial division of the Faroe Shelf should be considered when studying biology and hydrography in these waters. A positive correlation between annual means on the outer Faroe Shelf and parts of the outer northwest Scottish Shelf indicates similarities between these neighbouring regions. We suggest that this similarity arises from the commonality in nutrient composition of the water masses shared by these neighbouring regions.

  2. Southeast Asia Report

    DTIC Science & Technology

    1987-05-05

    With NASA 13 New Gas Find 14 Transmigration From Central Java 14 Transmigration From West Java 14 Bali’s Rice Fields Decreasing 14 Trade Surplus...Mar 87 p A2] /9274 RESEARCH PROGRAM WITH NASA —Indonesia is still hoping for the continuation of the outer space research program by Dr Pratiwi...Sudharmono under NASA program, Tourist. Post, and Telecommunications Minister Akhmad Tahir said in Jakarta yesterday. The minister said he was still

  3. Particle-in-cell simulations of electron beam control using an inductive current divider

    DOE PAGES

    Swanekamp, S. B.; Angus, J. R.; Cooperstein, G.; ...

    2015-11-18

    Kinetic, time-dependent, electromagnetic, particle-in-cell simulations of the inductive current divider are presented. The inductive current divider is a passive method for controlling the trajectory of an intense, hollow electron beam using a vacuum structure that inductively splits the beam’s return current. The current divider concept was proposed and studied theoretically in a previous publication [Phys. Plasmas 22, 023107 (2015)] A central post carries a portion of the return current (I 1) while the outer conductor carries the remainder (I 2) with the injected beam current given by I b=I 1+I 2. The simulations are in agreement with the theory whichmore » predicts that the total force on the beam trajectory is proportional to (I 2-I 1) and the force on the beam envelope is proportional to I b. For a fixed central post, the beam trajectory is controlled by varying the outer conductor radius which changes the inductance in the return-current path. The simulations show that the beam emittance is approximately constant as the beam propagates through the current divider to the target. As a result, independent control over both the current density and the beam angle at the target is possible by choosing the appropriate return-current geometry.« less

  4. Structure of a prokaryotic sodium channel pore reveals essential gating elements and an outer ion binding site common to eukaryotic channels

    PubMed Central

    Shaya, David; Findeisen, Felix; Abderemane-Ali, Fayal; Arrigoni, Cristina; Wong, Stephanie; Nurva, Shailika Reddy; Loussouarn, Gildas; Minor, Daniel L.

    2013-01-01

    Voltage-gated sodium channels (NaVs) are central elements of cellular excitation. Notwithstanding advances from recent bacterial NaV (BacNaV) structures, key questions about gating and ion selectivity remain. Here, we present a closed conformation of NaVAe1p, a pore-only BacNaV derived from NaVAe1, a BacNaV from the arsenite oxidizer Alkalilimnicola ehrlichei found in Mono Lake, California, that provides insight into both fundamental properties. The structure reveals a pore domain in which the pore-lining S6 helix connects to a helical cytoplasmic tail. Electrophysiological studies of full-length BacNaVs show that two elements defined by the NaVAe1p structure, an S6 activation gate position and the cytoplasmic tail ‘neck’, are central to BacNaV gating. The structure also reveals the selectivity filter ion entry site, termed the ‘outer ion’ site. Comparison with mammalian voltage-gated calcium channel (CaV) selectivity filters, together with functional studies shows that this site forms a previously unknown determinant of CaV high affinity calcium binding. Our findings underscore commonalities between BacNaVs and eukaryotic voltage-gated channels and provide a framework for understanding gating and ion permeation in this superfamily. PMID:24120938

  5. Spatial accumulation pattern of citrulline and other nutrients in immature and mature watermelon fruits.

    PubMed

    Akashi, Kinya; Mifune, Yuki; Morita, Kaori; Ishitsuka, Souichi; Tsujimoto, Hisashi; Ishihara, Toshiyuki

    2017-01-01

    Watermelon (Citrullus lanatus L.) originates from arid regions of southern Africa, and its fruit contains a large amount of the amino acid citrulline, an efficient hydroxyl radical scavenger. Citrulline is implicated in the production of nitric oxide in human endothelium, and potential health benefits including vasodilatation and antioxidant functions have been suggested. However, citrulline metabolism in watermelon fruits is poorly understood. This study examined the accumulation pattern of citrulline and other nutrients in immature and mature watermelon fruits. In mature fruits, highest citrulline concentration was observed in the outer peel, followed by the central portion of the flesh and inner rinds, whereas the level was lower in the peripheral portion of the flesh. Citrulline content was generally low in immature fruits. Spatial and developmental patterns of citrulline accumulation were largely different from those of the antioxidant lycopene, total proteins, and soluble sugars such as glucose, fructose, and sucrose. Principal component analysis suggested a clear distinction of the central flesh and outer peels in mature fruits from other tissues in terms of the levels of major nutrients. These observations suggested that citrulline accumulation may be regulated in a distinct manner from other nutrients during watermelon fruit maturation. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  6. A photoevaporative gap in the closest planet-forming disc

    NASA Astrophysics Data System (ADS)

    Ercolano, Barbara; Rosotti, Giovanni P.; Picogna, Giovanni; Testi, Leonardo

    2017-01-01

    The dispersal of the circum-stellar discs of dust and gas surrounding young low-mass stars has important implications for the formation of planetary systems. Photoevaporation from energetic radiation from the central object is thought to drive the dispersal in the majority of discs, by creating a gap which disconnects the outer from the inner regions of the disc and then disperses the outer disc from the inside-out, while the inner disc keeps draining viscously on to the star. In this Letter, we show that the disc around TW Hya, the closest protoplanetary disc to Earth, may be the first object where a photoevaporative gap has been imaged around the time at which it is being created. Indeed, the detected gap in the Atacama large millimeter/submillimeter array images is consistent with the expectations of X-ray photoevaporation models, thus not requiring the presence of a planet. The photoevaporation model is also consistent with a broad range of properties of the TW Hya system, e.g. accretion rate and the location of the gap at the onset of dispersal. We show that the central, unresolved 870 μm continuum source might be produced by free-free emission from the gas and/or residual dust inside the gap.

  7. Featured Image: A New Look at Fomalhaut

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2017-06-01

    ALMA continuum image overlaid as contours on the Hubble STIS image of Fomalhaut. [MacGregor et al. 2017]This stunning image of the Fomalhaut star system was taken by the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile. This image maps the 1.3-mm continuum emission from the dust around the central star, revealing a ring that marks the outer edge of the planet-forming debris disk surrounding the star. In a new study, a team of scientists led by Meredith MacGregor (Harvard-Smithsonian Center for Astrophysics) examines these ALMA observations of Fomalhaut, which beautifully complement former Hubble images of the system. ALMAs images provide the first robust detection of apocenter glow the brightening of the ring at the point farthest away from the central star, a side effect of the rings large eccentricity. The authors use ALMAsobservations to measure properties of the disk, such as its span (roughly 136 x 14 AU), eccentricity (e 0.12), and inclination angle ( 66). They then explore the implications for Fomalhaut b, the planet located near the outer disk. To read more about the teams observations, check out the paper below.CitationMeredith A. MacGregor et al 2017 ApJ 842 8. doi:10.3847/1538-4357/aa71ae

  8. Shear-wave elastography - virtual touch tissue quantification of fetal placentas with a single umbilical artery.

    PubMed

    Arslan, Harun; Tolunay, Harun Egemen; Cim, Numan; Boza, Barış; Yavuz, Alpaslan; İlik, İbrahim; Sahin, Hanim Guler; Yildizhan, Recep

    2018-02-25

    In this study, we aimed to evaluate the elasticities of fetal placentas with a single umbilical artery using the Virtual Touch Tissue Quantification (VTTQ) technique. Pregnant women with fetuses with a single umbilical artery (SUA) and pregnant women with fetuses having three vessel cord (3VC) at 18-22 weeks of gestation were enrolled in the research. The placentas were evaluated and divided into three equal parts as the inner 1/3 of the placenta (fetal edge), the outer 1/3 of the placenta (maternal edge) and the central 1/3 of the placenta (central part). Shear-wave velocity (SWV) measurements were used in the elastographic evaluation of placentas by VTTQ. Forty pregnant women were included in the study (n = 20 SUA, n = 20 three vessel cord pregnant women). The placental Acoustic Radiation Force Impulse (VTTQ) of the placenta regarding SWV measurement values of the fetal edge of the placenta in the fetuses with SUA and the control group were 0.876 and 0.957 m/sec, respectively. A significant statistical difference was found between the groups regarding the measurement of the stiffness of fetal placenta (p = 0.021). There was no significant difference between the measured stiffness values of the central or outer region of the placentas. In this study, we found lower SWV scores for the fetal edge of the placenta with SUA. This finding may reflect tissue elasticity level, and we hope that the use of the VTTQ technique may contribute to predicting the pregnancy-related morbidities of fetuses with SUA in the future.

  9. Ganymede Impact Crater Morphology as Revealed by Galileo

    NASA Astrophysics Data System (ADS)

    Weitz, C. M.; Head, J. W.; Pappalardo, R.; Chapman, C.; Greeley, R.; Helfenstein, P.; Neukum, G.; Galileo SSI Team

    1997-07-01

    We have used the Galileo G1, G2, G7, and G8 images to study the morpholo- gy and degradation of impact craters on Ganymede. Results from the G1 and G2 data showed three types of degradation states: pristine, partially degraded, and heavily degraded. With the more recent G7 and G8 images, there are now several other distinct crater morphologies that we have identified. Enki Catena is about 120 km in length and consists of 13 attached impact craters. The six craters in the chain that impacted onto the bright terrain have visible bright ejecta while those that impacted onto the dark terrain have barely visible ejecta. Kittu crater is about 15 km in diameter and it has a bright central peak surrounded by a bright floor and hummocky wall material. The crater rim in the north is linear in appearance at the location that corresponds to the boundary between the groove terrain and the adjacent dark terrain, indicating structural control by the underlying topography. The dark rays that are easily seen in the Voyager images are barely visible in the Galileo image. Neith crater has a central fractured dome surrounded by a jagged central ring, smoother outer ejecta facies, and less prominent outer rings. Achelous crater and its neighbor, which were imaged at low sun angle to show topography, have smooth floors and subdued pedestal ejecta. Nicholson Regio has tectonically disrupted craters on the groove and fractured terrains while the surrounding smoother dark terrain has numerous degrad- ed craters that may indicate burial by resurfacing or by regolith development.

  10. Toxicity of irradiated advanced heavy water reactor fuels.

    PubMed

    Priest, N D; Richardson, R B; Edwards, G W R

    2013-02-01

    The good neutron economy and online refueling capability of the CANDU® heavy water moderated reactor (HWR) enable it to use many different fuels such as low enriched uranium (LEU), plutonium, or thorium, in addition to its traditional natural uranium (NU) fuel. The toxicity and radiological protection methods for these proposed fuels, unlike those for NU, are not well established. This study uses software to compare the fuel composition and toxicity of irradiated NU fuel against those of two irradiated advanced HWR fuel bundles as a function of post-irradiation time. The first bundle investigated is a CANFLEX® low void reactor fuel (LVRF), of which only the dysprosium-poisoned central element, and not the outer 42 LEU elements, is specifically analyzed. The second bundle investigated is a heterogeneous high-burnup (LEU,Th)O(2) fuelled bundle, whose two components (LEU in the outer 35 elements and thorium in the central eight elements) are analyzed separately. The LVRF central element was estimated to have a much lower toxicity than that of NU at all times after shutdown. Both the high burnup LEU and the thorium fuel had similar toxicity to NU at shutdown, but due to the creation of such inhalation hazards as (238)Pu, (240)Pu, (242)Am, (242)Cm, and (244)Cm (in high burnup LEU), and (232)U and (228)Th (in irradiated thorium), the toxicity of these fuels was almost double that of irradiated NU after 2,700 d of cooling. New urine bioassay methods for higher actinoids and the analysis of thorium in fecal samples are recommended to assess the internal dose from these two fuels.

  11. Co-training Framework of Generative and Disciminative Trackers with Partial Occlusion Handling

    DTIC Science & Technology

    2011-01-01

    ARO W911NF-06-1-0094. The first author was also supported by the Vietnam Education Foundation. We thank Zdenek Kalal for his help with the P-N Tracker...handling challenging situations with cluttered background. Recently, Kalal et al. [11] proposed the P-N Tracker us- ing positive and negative constraints to...Vietnam Education Foundation. We thank Zdenek Kalal for his help with the P-N Tracker [11]. References [1] A. Adam, E. Rivlin, and I. Shimshoni. Robust

  12. Measuring Scale Errors in a Laser Tracker’s Horizontal Angle Encoder Through Simple Length Measurement and Two-Face System Tests

    PubMed Central

    Muralikrishnan, B.; Blackburn, C.; Sawyer, D.; Phillips, S.; Bridges, R.

    2010-01-01

    We describe a method to estimate the scale errors in the horizontal angle encoder of a laser tracker in this paper. The method does not require expensive instrumentation such as a rotary stage or even a calibrated artifact. An uncalibrated but stable length is realized between two targets mounted on stands that are at tracker height. The tracker measures the distance between these two targets from different azimuthal positions (say, in intervals of 20° over 360°). Each target is measured in both front face and back face. Low order harmonic scale errors can be estimated from this data and may then be used to correct the encoder’s error map to improve the tracker’s angle measurement accuracy. We have demonstrated this for the second order harmonic in this paper. It is important to compensate for even order harmonics as their influence cannot be removed by averaging front face and back face measurements whereas odd orders can be removed by averaging. We tested six trackers from three different manufacturers. Two of those trackers are newer models introduced at the time of writing of this paper. For older trackers from two manufacturers, the length errors in a 7.75 m horizontal length placed 7 m away from a tracker were of the order of ± 65 μm before correcting the error map. They reduced to less than ± 25 μm after correcting the error map for second order scale errors. Newer trackers from the same manufacturers did not show this error. An older tracker from a third manufacturer also did not show this error. PMID:27134789

  13. Counting Steps in Activities of Daily Living in People With a Chronic Disease Using Nine Commercially Available Fitness Trackers: Cross-Sectional Validity Study

    PubMed Central

    Beekman, Emmylou; Theunissen, Kyra; Braun, Susy; Beurskens, Anna J

    2018-01-01

    Background Measuring physical activity with commercially available activity trackers is gaining popularity. People with a chronic disease can especially benefit from knowledge about their physical activity pattern in everyday life since sufficient physical activity can contribute to wellbeing and quality of life. However, no validity data are available for this population during activities of daily living. Objective The aim of this study was to investigate the validity of 9 commercially available activity trackers for measuring step count during activities of daily living in people with a chronic disease receiving physiotherapy. Methods The selected activity trackers were Accupedo (Corusen LLC), Activ8 (Remedy Distribution Ltd), Digi-Walker CW-700 (Yamax), Fitbit Flex (Fitbit inc), Lumoback (Lumo Bodytech), Moves (ProtoGeo Oy), Fitbit One (Fitbit inc), UP24 (Jawbone), and Walking Style X (Omron Healthcare Europe BV). In total, 130 persons with chronic diseases performed standardized activity protocols based on activities of daily living that were recorded on video camera and analyzed for step count (gold standard). The validity of the trackers’ step count was assessed by correlation coefficients, t tests, scatterplots, and Bland-Altman plots. Results The correlations between the number of steps counted by the activity trackers and the gold standard were low (range: –.02 to .33). For all activity trackers except for Fitbit One, a significant systematic difference with the gold standard was found for step count. Plots showed a wide range in scores for all activity trackers; Activ8 showed an average overestimation and the other 8 trackers showed underestimations. Conclusions This study showed that the validity of 9 commercially available activity trackers is low measuring steps while individuals with chronic diseases receiving physiotherapy engage in activities of daily living. PMID:29610110

  14. Reliability and Validity of Ten Consumer Activity Trackers Depend on Walking Speed.

    PubMed

    Fokkema, Tryntsje; Kooiman, Thea J M; Krijnen, Wim P; VAN DER Schans, Cees P; DE Groot, Martijn

    2017-04-01

    To examine the test-retest reliability and validity of ten activity trackers for step counting at three different walking speeds. Thirty-one healthy participants walked twice on a treadmill for 30 min while wearing 10 activity trackers (Polar Loop, Garmin Vivosmart, Fitbit Charge HR, Apple Watch Sport, Pebble Smartwatch, Samsung Gear S, Misfit Flash, Jawbone Up Move, Flyfit, and Moves). Participants walked three walking speeds for 10 min each; slow (3.2 km·h), average (4.8 km·h), and vigorous (6.4 km·h). To measure test-retest reliability, intraclass correlations (ICC) were determined between the first and second treadmill test. Validity was determined by comparing the trackers with the gold standard (hand counting), using mean differences, mean absolute percentage errors, and ICC. Statistical differences were calculated by paired-sample t tests, Wilcoxon signed-rank tests, and by constructing Bland-Altman plots. Test-retest reliability varied with ICC ranging from -0.02 to 0.97. Validity varied between trackers and different walking speeds with mean differences between the gold standard and activity trackers ranging from 0.0 to 26.4%. Most trackers showed relatively low ICC and broad limits of agreement of the Bland-Altman plots at the different speeds. For the slow walking speed, the Garmin Vivosmart and Fitbit Charge HR showed the most accurate results. The Garmin Vivosmart and Apple Watch Sport demonstrated the best accuracy at an average walking speed. For vigorous walking, the Apple Watch Sport, Pebble Smartwatch, and Samsung Gear S exhibited the most accurate results. Test-retest reliability and validity of activity trackers depends on walking speed. In general, consumer activity trackers perform better at an average and vigorous walking speed than at a slower walking speed.

  15. Individual Differences in the Attribution of Incentive Salience to a Pavlovian Alcohol Cue.

    PubMed

    Villaruel, Franz R; Chaudhri, Nadia

    2016-01-01

    Individual differences exist in the attribution of incentive salience to conditioned stimuli associated with food. Here, we investigated whether individual differences also manifested with a Pavlovian alcohol conditioned stimulus (CS). We compiled data from five experiments that used a Pavlovian autoshaping paradigm and tests of conditioned reinforcement. In all experiments, male, Long-Evans rats with unrestricted access to food and water were acclimated to 15% ethanol. Next, rats received Pavlovian autoshaping training, in which a 10 s presentation of a retractable lever served as the CS and 0.2 mL of 15% ethanol served as the unconditioned stimulus (US). Finally, rats underwent conditioned reinforcement tests in which nose-pokes to an active aperture led to brief presentations of the lever-CS, but nose-pokes to an inactive aperture had no consequence. Rats were categorized as sign-trackers, goal-trackers and intermediates based on a response bias score that reflected their tendencies to sign-track or goal-track at different times during training. We found that distinct groups of rats either consistently interacted with the lever-CS ("sign-trackers") or routinely approached the port during the lever-CS ("goal-trackers") across a majority of the training sessions. However, some individuals ("shifted sign-trackers") with an early tendency to goal-track later shifted to comparable asymptotic levels of sign-tracking as the group identified as sign-trackers. The lever-CS functioned as a conditioned reinforcer for sign-trackers and shifted sign-trackers, but not for goal-trackers. These results provide evidence of robust individual differences in the extent to which a Pavlovian alcohol cue gains incentive salience and functions as a conditioned reinforcer.

  16. Precision Attitude Determination System (PADS) design and analysis. Two-axis gimbal star tracker

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Development of the Precision Attitude Determination System (PADS) focused chiefly on the two-axis gimballed star tracker and electronics design improved from that of Precision Pointing Control System (PPCS), and application of the improved tracker for PADS at geosynchronous altitude. System design, system analysis, software design, and hardware design activities are reported. The system design encompasses the PADS configuration, system performance characteristics, component design summaries, and interface considerations. The PADS design and performance analysis includes error analysis, performance analysis via attitude determination simulation, and star tracker servo design analysis. The design of the star tracker and electronics are discussed. Sensor electronics schematics are included. A detailed characterization of the application software algorithms and computer requirements is provided.

  17. The IR properties of ringed galaxies and the IRAS database

    NASA Technical Reports Server (NTRS)

    Buta, Ronald J.; Crocker, Deborah A.

    1993-01-01

    Our study of the Infrared Astronomy Satellite (IRAS) properties of ringed galaxies has been largely successful. We have identified what we think is the probable cause of the differences in the IRAS properties among non-interacting barred galaxies as the pattern speed of the bar. The key to identifying this parameter has been our focusing the study on outer-ringed galaxies where we know precisely what is present in the central regions (from available BVI CCD images in our library of images). The theory is that outer rings, through their morphology and other characteristics, can be identified with the outer Lindblad resonance, one of the major resonances in galaxy structure. Using a library of n-body simulations for comparison, we can reliably infer both low and high pattern speed galaxies from the appearance of outer rings and the existence of other ring features. It is clear that in some barred galaxies, the bar pattern speed is high enough to avoid an inner Lindblad resonance, hence such objects do not contain nuclear or circumnuclear star formation. The IRAS observations are most sensitive to nuclear star formation in early-type barred galaxies, and will thus select those barred galaxies where the pattern speed is low enough to allow an inner Lindblad resonance to exist. High pattern speed barred galaxies therefore weaken the correlation between bars and infrared excess. This finding helps to reconcile the inconsistent results found between different studies on the correlation between bars and far-IR emission.

  18. Sun tracker for clear or cloudy weather

    NASA Technical Reports Server (NTRS)

    Scott, D. R.; White, P. R.

    1979-01-01

    Sun tracker orients solar collector so that they absorb maximum possible sunlight without being fooled by bright clouds, holes in cloud cover, or other atmospheric conditions. Tracker follows sun within 0.25 deg arc and is accurate within + or - 5 deg when sun is hidden.

  19. Advantages and Limitations of Wearable Activity Trackers: Considerations for Patients and Clinicians.

    PubMed

    Walker, Rachel K; Hickey, Amanda M; Freedson, Patty S

    2016-12-01

    Exercise, light physical activity, and decreased sedentary time all have been associated with health benefits following cancer diagnoses. Commercially available wearable activity trackers may help patients monitor and self-manage their behaviors to achieve these benefits. This article highlights some advantages and limitations clinicians should be aware of when discussing the use of activity trackers with cancer survivors. Limited research has assessed the accuracy of commercially available activity trackers compared to research-grade devices. Because most devices use confidential, proprietary algorithms to convert accelerometry data to meaningful output like total steps, assessing whether these algorithms account for differences in gait abnormalities, functional limitations, and different body morphologies can be difficult. Quantification of sedentary behaviors and light physical activities present additional challenges. The global market for activity trackers is growing, which presents clinicians with a tremendous opportunity to incorporate these devices into clinical practice as tools to promote activity. This article highlights important considerations about tracker accuracy and usage by cancer survivors.

  20. Physical understanding of the tropical cyclone wind-pressure relationship.

    PubMed

    Chavas, Daniel R; Reed, Kevin A; Knaff, John A

    2017-11-08

    The relationship between the two common measures of tropical cyclone intensity, the central pressure deficit and the peak near-surface wind speed, is a long-standing problem in tropical meteorology that has been approximated empirically yet lacks physical understanding. Here we provide theoretical grounding for this relationship. We first demonstrate that the central pressure deficit is highly predictable from the low-level wind field via gradient wind balance. We then show that this relationship reduces to a dependence on two velocity scales: the maximum azimuthal-mean azimuthal wind speed and half the product of the Coriolis parameter and outer storm size. This simple theory is found to hold across a hierarchy of models spanning reduced-complexity and Earth-like global simulations and observations. Thus, the central pressure deficit is an intensity measure that combines maximum wind speed, storm size, and background rotation rate. This work has significant implications for both fundamental understanding and risk analysis, including why the central pressure better explains historical economic damages than does maximum wind speed.

  1. ITER CS Model Coil and CS Insert Test Results

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

    Martovetsky, N; Michael, P; Minervina, J

    2000-09-07

    The Inner and Outer modules of the Central Solenoid Model Coil (CSMC) were built by US and Japanese home teams in collaboration with European and Russian teams to demonstrate the feasibility of a superconducting Central Solenoid for ITER and other large tokamak reactors. The CSMC mass is about 120 t, OD is about 3.6 m and the stored energy is 640 MJ at 46 kA and peak field of 13 T. Testing of the CSMC and the CS Insert took place at Japan Atomic Energy Research Institute (JAERI) from mid March until mid August 2000. This paper presents the mainmore » results of the tests performed.« less

  2. Commodity Tracker: Mobile Application for Food Security Monitoring in Haiti

    NASA Astrophysics Data System (ADS)

    Chiu, M. T.; Huang, X.; Baird, J.; Gourley, J. R.; Morelli, R.; de Lanerolle, T. R.; Haiti Food Security Monitoring Mobile App Team

    2011-12-01

    Megan Chiu, Jason Baird, Xu Huang, Trishan de Lanerolle, Ralph Morelli, Jonathan Gourley Trinity College, Computer Science Department and Environmental Science Program, 300 Summit Street, Hartford, CT 06106 megan.chiu@trincoll.edu, Jason.baird@trincoll.edu, xu.huang@trincoll.edu, trishan.delanerolle@trincoll.edu, ralph.morelli@trincoll.edu, jonathan.gourley@trincoll.edu Price data for Haiti commodities such as rice and potatoes have been traditionally recorded by hand on paper forms for many years. The information is then entered onto computer manually, thus making the process a long and arduous one. With the development of the Haiti Commodity Tracker mobile app, we are able to make this commodity price data recording process more efficient. Officials may use this information for making inferences about the difference in commodity prices and for food distribution during critical time after natural disasters. This information can also be utilized by governments and aid agencies on their food assistance programs. Agronomists record the item prices from several sample sites in a marketplace and compare those results from other markets across the region. Due to limited connectivity in rural areas, data is first saved to the phone's database and then retransmitted to a central server via SMS messaging. The mobile app is currently being field tested by an international NGO providing agricultural aid and support in rural Haiti.

  3. ν{sub μ} CCπ° reaction in the tracker of the ND280 detector in the T2K experiment

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

    Batkiewicz, Marcela

    A good knowledge of both inclusive and exclusive neutrino interaction cross sections is one of the key issues for a precise determination of the neutrino oscillation parameters in the T2K experiment. These studies are performed at the near detector (ND280). Its central tracker part equipped with a water target is used, among others, to study the ν{sub μ}CCπ° reaction. At the energies of the T2K neutrino beam its contribution to the total cross section is relatively large, so the reaction is a potential source of the background for the quasi-elastic ν{sub μ}CC reaction. Two different production mechanisms contribute to ν{submore » μ}CCπ°: single pion resonance production and Deep Inelastic Scattering (DIS). In addition, Final State Interactions (FSI) have to be considered. Thus, the analysis of the ν{sub μ}CCπ° reaction aims also at a better tuning of the Monte Carlo (MC) models used to describe neutrino interactions in T2K. This paper describes selection criteria leading to the determination of the inclusive and exclusive cross sections for the π° production in the ν{sub μ}CC interactions.« less

  4. Air Pollution Exposure Modeling for Health Studies | Science ...

    EPA Pesticide Factsheets

    Dr. Michael Breen is leading the development of air pollution exposure models, integrated with novel personal sensor technologies, to improve exposure and risk assessments for individuals in health studies. He is co-investigator for multiple health studies assessing the exposure and effects of air pollutants. These health studies include participants with asthma, diabetes, and coronary artery disease living in various U.S. cities. He has developed, evaluated, and applied novel exposure modeling and time-activity tools, which includes the Exposure Model for Individuals (EMI), GPS-based Microenvironment Tracker (MicroTrac) and Exposure Tracker models. At this seminar, Dr. Breen will present the development and application of these models to predict individual-level personal exposures to particulate matter (PM) for two health studies in central North Carolina. These health studies examine the association between PM and adverse health outcomes for susceptible individuals. During Dr. Breen’s visit, he will also have the opportunity to establish additional collaborations with researchers at Harvard University that may benefit from the use of exposure models for cohort health studies. These research projects that link air pollution exposure with adverse health outcomes benefit EPA by developing model-predicted exposure-dose metrics for individuals in health studies to improve the understanding of exposure-response behavior of air pollutants, and to reduce participant

  5. Spacecraft angular velocity estimation algorithm for star tracker based on optical flow techniques

    NASA Astrophysics Data System (ADS)

    Tang, Yujie; Li, Jian; Wang, Gangyi

    2018-02-01

    An integrated navigation system often uses the traditional gyro and star tracker for high precision navigation with the shortcomings of large volume, heavy weight and high-cost. With the development of autonomous navigation for deep space and small spacecraft, star tracker has been gradually used for attitude calculation and angular velocity measurement directly. At the same time, with the dynamic imaging requirements of remote sensing satellites and other imaging satellites, how to measure the angular velocity in the dynamic situation to improve the accuracy of the star tracker is the hotspot of future research. We propose the approach to measure angular rate with a nongyro and improve the dynamic performance of the star tracker. First, the star extraction algorithm based on morphology is used to extract the star region, and the stars in the two images are matched according to the method of angular distance voting. The calculation of the displacement of the star image is measured by the improved optical flow method. Finally, the triaxial angular velocity of the star tracker is calculated by the star vector using the least squares method. The method has the advantages of fast matching speed, strong antinoise ability, and good dynamic performance. The triaxial angular velocity of star tracker can be obtained accurately with these methods. So, the star tracker can achieve better tracking performance and dynamic attitude positioning accuracy to lay a good foundation for the wide application of various satellites and complex space missions.

  6. Experimental predictions drawn from a computational model of sign-trackers and goal-trackers.

    PubMed

    Lesaint, Florian; Sigaud, Olivier; Clark, Jeremy J; Flagel, Shelly B; Khamassi, Mehdi

    2015-01-01

    Gaining a better understanding of the biological mechanisms underlying the individual variation observed in response to rewards and reward cues could help to identify and treat individuals more prone to disorders of impulsive control, such as addiction. Variation in response to reward cues is captured in rats undergoing autoshaping experiments where the appearance of a lever precedes food delivery. Although no response is required for food to be delivered, some rats (goal-trackers) learn to approach and avidly engage the magazine until food delivery, whereas other rats (sign-trackers) come to approach and engage avidly the lever. The impulsive and often maladaptive characteristics of the latter response are reminiscent of addictive behaviour in humans. In a previous article, we developed a computational model accounting for a set of experimental data regarding sign-trackers and goal-trackers. Here we show new simulations of the model to draw experimental predictions that could help further validate or refute the model. In particular, we apply the model to new experimental protocols such as injecting flupentixol locally into the core of the nucleus accumbens rather than systemically, and lesioning of the core of the nucleus accumbens before or after conditioning. In addition, we discuss the possibility of removing the food magazine during the inter-trial interval. The predictions from this revised model will help us better understand the role of different brain regions in the behaviours expressed by sign-trackers and goal-trackers. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Post flight analysis of NASA standard star trackers recovered from the solar maximum mission

    NASA Technical Reports Server (NTRS)

    Newman, P.

    1985-01-01

    The flight hardware returned after the Solar Maximum Mission Repair Mission was analyzed to determine the effects of 4 years in space. The NASA Standard Star Tracker would be a good candidate for such analysis because it is moderately complex and had a very elaborate calibration during the acceptance procedure. However, the recovery process extensively damaged the cathode of the image dissector detector making proper operation of the tracker and a comparison with preflight characteristics impossible. Otherwise, the tracker functioned nominally during testing.

  8. Personal Activity Trackers and the Quantified Self.

    PubMed

    Hoy, Matthew B

    2016-01-01

    Personal activity trackers are an inexpensive and easy way for people to record their physical activity and simple biometric data. As these devices have increased in availability and sophistication, their use in daily life and in medicine has grown. This column will briefly explore what these devices are, what types of data they can track, and how that data can be used. It will also discuss potential problems with trackers and how librarians can help patients and physicians manage and protect activity data. A brief list of currently available activity trackers is also included.

  9. One-kilohertz eye tracker and active intraoperative torsion detection in the NIDEK CXIII and Quest excimer lasers.

    PubMed

    Waring, George O

    2009-10-01

    To describe recent technological additions to the NIDEK CXIII and Quest excimer lasers. A summary article with data from previous published studies outlining the benefits of newer technology. The addition of a 1-kHz infrared eye tracker decreased the spread of laser spot placement from a mean of 228.79 microm without a tracker to 38.47 microm with the eye tracker. The addition of real-time torsion error correction produced a statistically significantly lower cylinder dispersion, mean manifest refractive cylinder, and error of angle postoperatively in eyes that underwent LASIK. The incorporation of an ultrahigh speed eye tracker and active cyclotorsion correction surpasses the minimal technology criteria required for accurate wavefront-based ablations. Copyright 2009, SLACK Incorporated.

  10. Log-polar mapping-based scale space tracking with adaptive target response

    NASA Astrophysics Data System (ADS)

    Li, Dongdong; Wen, Gongjian; Kuai, Yangliu; Zhang, Ximing

    2017-05-01

    Correlation filter-based tracking has exhibited impressive robustness and accuracy in recent years. Standard correlation filter-based trackers are restricted to translation estimation and equipped with fixed target response. These trackers produce an inferior performance when encountered with a significant scale variation or appearance change. We propose a log-polar mapping-based scale space tracker with an adaptive target response. This tracker transforms the scale variation of the target in the Cartesian space into a shift along the logarithmic axis in the log-polar space. A one-dimensional scale correlation filter is learned online to estimate the shift along the logarithmic axis. With the log-polar representation, scale estimation is achieved accurately without a multiresolution pyramid. To achieve an adaptive target response, a variance of the Gaussian function is computed from the response map and updated online with a learning rate parameter. Our log-polar mapping-based scale correlation filter and adaptive target response can be combined with any correlation filter-based trackers. In addition, the scale correlation filter can be extended to a two-dimensional correlation filter to achieve joint estimation of the scale variation and in-plane rotation. Experiments performed on an OTB50 benchmark demonstrate that our tracker achieves superior performance against state-of-the-art trackers.

  11. ABUNDANCES OF PLANETARY NEBULAE IN THE OUTER DISK OF M31

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

    Kwitter, Karen B.; Lehman, Emma M. M.; Balick, Bruce

    2012-07-01

    We present spectroscopic observations and chemical abundances of 16 planetary nebulae (PNe) in the outer disk of M31. The [O III] {lambda}4363 line is detected in all objects, allowing a direct measurement of the nebular temperature essential for accurate abundance determinations. Our results show that the abundances in these M31 PNe display the same correlations and general behaviors as Type II PNe in the Milky Way. We also calculate photoionization models to derive estimates of central star properties. From these we infer that our sample PNe, all near the bright-end cutoff of the planetary nebula luminosity function, originated from starsmore » near 2 M{sub Sun }. Finally, under the assumption that these PNe are located in M31's disk, we plot the oxygen abundance gradient, which appears shallower than the gradient in the Milky Way.« less

  12. Accretion disc wind variability in the states of the microquasar GRS 1915+105

    NASA Astrophysics Data System (ADS)

    Neilsen, Joseph; Petschek, Andrew J.; Lee, Julia C.

    2012-03-01

    Continuing our study of the role and evolution of accretion disc winds in the microquasar GRS 1915+105, we present high-resolution spectral variability analysis of the β and γ states with the Chandra High-Energy Transmission Grating Spectrometer. By tracking changes in the absorption lines from the accretion disc wind, we find new evidence that radiation links the inner and outer accretion discs on a range of time-scales. As the central X-ray flux rises during the high-luminosity γ state, we observe the progressive overionization of the wind. In the β state, we argue that changes in the inner disc leading to the ejection of a transient 'baby jet' also quench the highly ionized wind from the outer disc. Our analysis reveals how the state, structure and X-ray luminosity of the inner accretion disc all conspire to drive the formation and variability of highly ionized accretion disc winds.

  13. Foveal damage in habitual poppers users.

    PubMed

    Audo, Isabelle; El Sanharawi, Mohamed; Vignal-Clermont, Catherine; Villa, Antoine; Morin, Annie; Conrath, John; Fompeydie, Dominique; Sahel, José-Alain; Gocho-Nakashima, Kiyoko; Goureau, Olivier; Paques, Michel

    2011-06-01

    To describe foveal damage in habitual use of poppers, a popular recreational drug. Retrospective observational case series. Six patients with bilateral vision loss after chronic popper inhalation were seen in 4 university-based ophthalmology departments. Symptoms, medical history, ophthalmic examination, and functional and morphological tests are described. All patients experienced progressive bilateral vision loss, with central photopsia in 2 cases. Initial visual acuities ranged from 20/50 to 20/25. In all patients, a bilateral yellow foveal spot was present that, by optical coherence tomography, was associated with disruption of the outer segments of foveal cones. Functional and anatomical damage was restricted to the fovea. The poppers involved were identified as isopropyl nitrite in 3 cases. Four patients showed anatomical and/or functional improvement over several months after discontinuing popper inhalation. Repeated inhalation of poppers may be associated with prolonged bilateral vision loss due to the disruption of foveal cone outer segments. Retinal damage may progressively improve following drug discontinuation.

  14. Genetic analysis of dTSPO, an outer mitochondrial membrane protein, reveals its functions in apoptosis, longevity, and Aβ42-induced neurodegeneration

    PubMed Central

    Lin, Ran; Angelin, Alessia; Da Settimo, Federico; Martini, Claudia; Taliani, Sabrina; Zhu, Shigong; Wallace, Douglas C

    2014-01-01

    The outer mitochondrial membrane (OMM) protein, the translocator protein 18 kDa (TSPO), formerly named the peripheral benzodiazepine receptor (PBR), has been proposed to participate in the pathogenesis of neurodegenerative diseases. To clarify the TSPO function, we identified the Drosophila homolog, CG2789/dTSPO, and studied the effects of its inactivation by P-element insertion, RNAi knockdown, and inhibition by ligands (PK11195, Ro5-4864). Inhibition of dTSPO inhibited wing disk apoptosis in response to γ-irradiation or H2O2 exposure, as well as extended male fly lifespan and inhibited Aβ42-induced neurodegeneration in association with decreased caspase activation. Therefore, dTSPO is an essential mediator of apoptosis in Drosophila and plays a central role in controlling longevity and neurodegenerative disease, making it a promising drug target. PMID:24977274

  15. Membrane recycling at the infranuclear pole of the outer hair cell

    NASA Astrophysics Data System (ADS)

    Harasztosi, Csaba; Harasztosi, Emese; Gummer, Anthony W.

    2015-12-01

    Rapid endocytic activity of outer hair cells (OHCs) in the guinea-pig cochlea has been already studied using the fluorescent membrane marker FM1-43. It was demonstrated that vesicles were endocytosed at the apical pole of OHCs and transcytosed to the basolateral membrane and through a central strand towards the nucleus. The significance of endocytic activity in the infranuclear region is still not clear. Therefore, in this study endocytic activity at the synaptic pole of OHCs was investigated. Confocal laser scanning microscopy was used to visualize dye uptake of OHCs isolated from the guinea-pig cochlea. Signal intensity changes were quantified in the apical and basal poles relative to the signal at the membrane. Data showed no significant difference in fluorescent signal intensity changes between the opposite poles of the OHC. These results suggest that endocytic activities in both the basal and the apical poles contribute equally to the membrane recycling of OHCs.

  16. Modeling of rapid shutdown in the DIII-D tokamak by core deposition of high-Z material

    DOE PAGES

    Izzo, Valerie A.; Parks, Paul B.

    2017-06-22

    MHD modeling of shell-pellet injection for disruption mitigation is carried out under the assumption of idealized delivery of the radiating payload to the core, neglecting the physics of shell ablation. The shell pellet method is designed to produce an inside-out thermal quench in which core thermal heat is radiated while outer flux surfaces remain intact, protecting the divertor from large conducted heat loads. In the simulation, good outer surfaces remain until the thermal quench is nearly complete, and a high radiated energy fraction is achieved. As a result, when the outermost surfaces are destroyed, runaway electron test orbits indicate thatmore » the rate of runaway electron loss is very fast compared with prior massive gas injection simulations, which is attributed to the very different current profile evolution that occurs with central cooling.« less

  17. Studies of azimuthal dihadron correlations in ultra-central PbPb collisions at $$\\sqrt{s_{NN}} =$$ 2.76 TeV

    DOE PAGES

    Chatrchyan, Serguei

    2014-02-20

    Azimuthal dihadron correlations of charged particles have been measured in PbPb collisions atmore » $$\\sqrt{s_{NN}}$$ = 2.76 TeV by the CMS collaboration, using data from the 2011 LHC heavy-ion run. The data set includes a sample of ultra-central (0-0.2% centrality) PbPb events collected using a trigger based on total transverse energy in the hadron forward calorimeters and the total multiplicity of pixel clusters in the silicon pixel tracker. A total of about 1.8 million ultra-central events were recorded, corresponding to an integrated luminosity of 120 inverse microbarns. The observed correlations in ultra-central PbPb events are expected to be particularly sensitive to initial-state fluctuations. The single-particle anisotropy Fourier harmonics, from $$v_2$$ to $$v_6$$, are extracted as a function of particle transverse momentum. At higher transverse momentum, the $$v_2$$ harmonic becomes significantly smaller than the higher-order $$v_n$$ (n greater than or equal to 3). The pt-averaged $$v_2$$ and $$v_3$$ are found to be equal within 2%, while higher-order $$v_n$$ decrease as n increases. The breakdown of factorization of dihadron correlations into single-particle azimuthal anisotropies is observed. This effect is found to be most prominent in the ultra-central PbPb collisions, where the initial-state fluctuations play a dominant role. As a result, a comparison of the factorization data to hydrodynamic predictions with event-by-event fluctuating initial conditions is also presented.« less

  18. 78 FR 9420 - Central Gulf of Mexico Planning Area (CPA) Outer Continental Shelf (OCS) Oil and Gas Lease Sale 227

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-08

    ... less than 400 meters. $100.00 per acre or fraction thereof for blocks in water depths of 400 meters or... less than 400 meters, and $100.00 per acre or fraction thereof for blocks in water depths of 400 meters... leases in 0 to less than 400 meters of water depth completed to a drilling depth of 20,000 feet TVD SS or...

  19. 75 FR 6874 - Outer Continental Shelf (OCS) Central Planning Area (CPA) Gulf of Mexico (GOM) Oil and Gas Lease...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-12

    ... for blocks in water depths of 400 meters to less than 1,600 meters. Blocks in 400 to less than 800... resulting from this lease sale. Leases in water depths of 400 meters to less than 800 meters will be offered... still may require the full 10-year term. In both the 400-800 and 800-1,600 meter cases, the lease...

  20. Suspected ivermectin toxicosis in a miniature mule foal causing blindness.

    PubMed

    Plummer, Caryn E; Kallberg, Maria E; Ollivier, Franck J; Brooks, Dennis E; Gelatt, Kirk N

    2006-01-01

    A 9-week-old miniature mule foal presented to the Veterinary Medical Teaching Hospital for acute blindness, ataxia, and depression following an overdose of an over-the-counter ivermectin-based de-worming medication. Ophthalmic examination and electrodiagnostic evaluation eliminated outer retinal abnormalities as the primary cause of the bilateral blindness, implicating instead a central neurologic effect of the drug. With symptomatic and supportive care, the foal recovered fully and regained its vision.

  1. Banded electromagnetic stator core

    DOEpatents

    Fanning, Alan W.; Gonzales, Aaron A.; Patel, Mahadeo R.; Olich, Eugene E.

    1994-01-01

    A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups.

  2. Banded electromagnetic stator core

    DOEpatents

    Fanning, Alan W.; Gonzales, Aaron A.; Patel, Mahadeo R.; Olich, Eugene E.

    1996-01-01

    A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups.

  3. The Physics of Tokamak Start-up

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

    D. Mueller

    Tokamak start-up on present-day devices usually relies on inductively induced voltage from a central solenoid. In some cases inductive startup is assisted with auxiliary power from electron cyclotron radio frequency heating. ITER, the National Spherical Torus eXperiment Upgrade and JT60, now under construction, will make use of the understanding gained from present-day devices to ensure successful start-up. Design of a spherical tokamak (ST) with DT capability for nuclear component testing would require an alternative to a central solenoid because the small central column in an ST has insufficient space to provide shielding for the insulators in the solenoid. Alternative start-upmore » techniques such as induction using outer poloidal field coils, electron Bernstein wave start-up, coaxial helicity injection and point source helicity injection have been used with success, but require demonstration of scaling to higher plasma current.« less

  4. The physics of tokamak start-up

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

    Mueller, D.

    Tokamak start-up on present-day devices usually relies on inductively induced voltage from a central solenoid. In some cases, inductive startup is assisted with auxiliary power from electron cyclotron radio frequency heating. International Thermonuclear Experimental Reactor, the National Spherical Torus Experiment Upgrade and JT60, now under construction, will make use of the understanding gained from present-day devices to ensure successful start-up. Design of a spherical tokamak (ST) with DT capability for nuclear component testing would require an alternative to a central solenoid because the small central column in an ST has insufficient space to provide shielding for the insulators in themore » solenoid. Alternative start-up techniques such as induction using outer poloidal field coils, electron Bernstein wave start-up, coaxial helicity injection, and point source helicity injection have been used with success, but require demonstration of scaling to higher plasma current.« less

  5. SU-E-I-16: Scan Length Dependency of the Radial Dose Distribution in a Long Polyethylene Cylinder

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

    Bakalyar, D; McKenney, S; Feng, W

    Purpose: The area-averaged dose in the central plane of a long cylinder following a CT scan depends upon the radial dose distribution and the length of the scan. The ICRU/TG200 phantom, a polyethylene cylinder 30 cm in diameter and 60 cm long, was the subject of this study. The purpose was to develop an analytic function that could determine the dose for a scan length L at any point in the central plane of this phantom. Methods: Monte Carlo calculations were performed on a simulated ICRU/TG200 phantom under conditions of cylindrically symmetric conditions of irradiation. Thus, the radial dose distributionmore » function must be an even function that accounts for two competing effects: The direct beam makes its weakest contribution at the center while the scatter begins abruptly at the outer radius and grows as the center is approached. The scatter contribution also increases with scan length with the increase approaching its limiting value at the periphery faster than along the central axis. An analytic function was developed that fit the data and possessed these features. Results: Symmetry and continuity dictate a local extremum at the center which is a minimum for the ICRU/TG200 phantom. The relative depth of the minimum decreases as the scan length grows and an absolute maximum can occur between the center and outer edge of the cylinders. As the scan length grows, the relative dip in the center decreases so that for very long scan lengths, the dose profile is relatively flat. Conclusion: An analytic function characterizes the radial and scan length dependency of dose for long cylindrical phantoms. The function can be integrated with the results expressed in closed form. One use for this is to help determine average dose distribution over the central cylinder plane for any scan length.« less

  6. Central Rotations of Milky Way Globular Clusters

    NASA Astrophysics Data System (ADS)

    Fabricius, Maximilian H.; Noyola, Eva; Rukdee, Surangkhana; Saglia, Roberto P.; Bender, Ralf; Hopp, Ulrich; Thomas, Jens; Opitsch, Michael; Williams, Michael J.

    2014-06-01

    Most Milky Way globular clusters (GCs) exhibit measurable flattening, even if on a very low level. Both cluster rotation and tidal fields are thought to cause this flattening. Nevertheless, rotation has only been confirmed in a handful of GCs, based mostly on individual radial velocities at large radii. We are conducting a survey of the central kinematics of Galactic GCs using the new Integral Field Unit instrument VIRUS-W. We detect rotation in all 11 GCs that we have observed so far, rendering it likely that a large majority of the Milky Way GCs rotate. We use published catalogs of GCs to derive central ellipticities and position angles. We show that in all cases where the central ellipticity permits an accurate measurement of the position angle, those angles are in excellent agreement with the kinematic position angles that we derive from the VIRUS-W velocity fields. We find an unexpected tight correlation between central rotation and outer ellipticity, indicating that rotation drives flattening for the objects in our sample. We also find a tight correlation between central rotation and published values for the central velocity dispersion, most likely due to rotation impacting the old dispersion measurements. This Letter includes data taken at The McDonald Observatory of The University of Texas at Austin.

  7. Aperture Synthesis C18O (1-0) Observations of L 1551 IRS5

    NASA Astrophysics Data System (ADS)

    Munetake, Momose; Nagayoshi, Ohashi; Ryohei, Kawabe; Takenori, Nakano; Masahiko, Hayashi

    We report aperture synthesis jceto observations of L1551 IRS5 with a spatial resolution of 2.8" x 2.5" using the Nobeyama Millimeter Array. We have detected an emission component centrally condensed around IRS 5, as well as a diffuse component extending in the north-south direction from the centrally condensed component. The centrally condensed component, 2380 AU x 1050 AU in size, is elongated in the direction perpendicular to the outflow axis, indicating the existence of a flattened circumstellar envelope around L1551 IRS5. The mass of the centrally condensed component is estimated to be 0.062 Mo. The position-velocity (P-V) diagrams reveal that the velocity field in the centrally condensed component is composed of infall and slight rotation. The infall velocity in the outer part is equal to the free-fall velocity around a central mass of ~0.1 Mo, e.g., 0.5 km/s at r = 700 AU, while the rotation velocity, 0.24 km/s at the same radius, gets prominent at inner radii with a radial dependence of r-1. The infall rate in the envelope is derived to be 6 times 10-6 Mo/yr from the radius and mass of the centrally condensed component, and the infall velocity.

  8. Infant Eyes: A Window on Cognitive Development

    ERIC Educational Resources Information Center

    Aslin, Richard N.

    2012-01-01

    Eye-trackers suitable for use with infants are now marketed by several commercial vendors. As eye-trackers become more prevalent in infancy research, there is the potential for users to be unaware of dangers lurking "under the hood" if they assume the eye-tracker introduces no errors in measuring infants' gaze. Moreover, the influx of voluminous…

  9. Analyzing Virtual Physics Simulations with Tracker

    ERIC Educational Resources Information Center

    Claessens, Tom

    2017-01-01

    In the physics teaching community, Tracker is well known as a user-friendly open source video analysis software, authored by Douglas Brown. With this tool, the user can trace markers indicated on a video or on stroboscopic photos and perform kinematic analyses. Tracker also includes a data modeling tool that allows one to fit some theoretical…

  10. Space Shuttle Star Tracker Challenges

    NASA Technical Reports Server (NTRS)

    Herrera, Linda M.

    2010-01-01

    The space shuttle fleet of avionics was originally designed in the 1970's. Many of the subsystems have been upgraded and replaced, however some original hardware continues to fly. Not only fly, but has proven to be the best design available to perform its designated task. The shuttle star tracker system is currently flying as a mixture of old and new designs, each with a unique purpose to fill for the mission. Orbiter missions have tackled many varied missions in space over the years. As the orbiters began flying to the International Space Station (ISS), new challenges were discovered and overcome as new trusses and modules were added. For the star tracker subsystem, the growing ISS posed an unusual problem, bright light. With two star trackers on board, the 1970's vintage image dissector tube (IDT) star trackers track the ISS, while the new solid state design is used for dim star tracking. This presentation focuses on the challenges and solutions used to ensure star trackers can complete the shuttle missions successfully. Topics include KSC team and industry partner methods used to correct pressurized case failures and track system performance.

  11. A UNIX SVR4-OS 9 distributed data acquisition for high energy physics

    NASA Astrophysics Data System (ADS)

    Drouhin, F.; Schwaller, B.; Fontaine, J. C.; Charles, F.; Pallares, A.; Huss, D.

    1998-08-01

    The distributed data acquisition (DAQ) system developed by the GRPHE (Groupe de Recherche en Physique des Hautes Energies) group is a combination of hardware and software dedicated to high energy physics. The system described here is used in the beam tests of the CMS tracker. The central processor of the system is a RISC CPU hosted in a VME card, running a POSIX compliant UNIX system. Specialized real-time OS9 VME cards perform the instrumentation control. The main data flow goes over a deterministic high speed network. The UNIX system manages a list of OS9 front-end systems with a synchronisation protocol running over a TCP/IP layer.

  12. J/ψ Suppression in In-In Collisions at 158 GeV/n

    NASA Astrophysics Data System (ADS)

    Arnaldi, Roberta; NA60 Collaboration

    2007-02-01

    The NA60 experiment has studied J/ψ production in Indium-Indium collisions at 158 AṡGeV. In this paper we present an updated set of results obtained with the complete set of available statistics and an improved alignment of the vertex tracker. The centrality dependence of the J/ψ production, obtained with an analysis technique based only on the J/ψ sample, indicates that a suppression beyond that induced by nuclear absorption is present in In-In collisions, setting in at ˜80 participant nucleons. A first study of the systematic errors related with this measurement is discussed. We also present preliminary results on the J/ψ azimuthal distributions.

  13. A low-cost, CCD solid state star tracker

    NASA Technical Reports Server (NTRS)

    Chmielowski, M.; Wynne, D.

    1992-01-01

    Applied Research Corporation (ARC) has developed an engineering model of a multi-star CCD-based tracker for space applications requiring radiation hardness, high reliability and low power consumption. The engineering unit compared favorably in functional performance tests to the standard NASA single-star tracker. Characteristics of the ARC star tracker are: field of view = 10 deg x 7.5 deg, sensitivity range of -1 to +5 star magnitude, NEA = 3 in x 3 in, linearity = 5 in x 5 in, and power consumption of 1-3 W (operating mode dependent). The software is upgradable through a remote link. The hardware-limited acquisition rate is 1-5 Hz for stars of +2 to +5 magnitude and 10-30 Hz for -1 to +2 magnitude stars. Mechanical and electrical interfaces are identical to the standard NASA star tracker.

  14. Intelligent error correction method applied on an active pixel sensor based star tracker

    NASA Astrophysics Data System (ADS)

    Schmidt, Uwe

    2005-10-01

    Star trackers are opto-electronic sensors used on-board of satellites for the autonomous inertial attitude determination. During the last years star trackers became more and more important in the field of the attitude and orbit control system (AOCS) sensors. High performance star trackers are based up today on charge coupled device (CCD) optical camera heads. The active pixel sensor (APS) technology, introduced in the early 90-ties, allows now the beneficial replacement of CCD detectors by APS detectors with respect to performance, reliability, power, mass and cost. The company's heritage in star tracker design started in the early 80-ties with the launch of the worldwide first fully autonomous star tracker system ASTRO1 to the Russian MIR space station. Jena-Optronik recently developed an active pixel sensor based autonomous star tracker "ASTRO APS" as successor of the CCD based star tracker product series ASTRO1, ASTRO5, ASTRO10 and ASTRO15. Key features of the APS detector technology are, a true xy-address random access, the multiple windowing read out and the on-chip signal processing including the analogue to digital conversion. These features can be used for robust star tracking at high slew rates and under worse conditions like stray light and solar flare induced single event upsets. A special algorithm have been developed to manage the typical APS detector error contributors like fixed pattern noise (FPN), dark signal non-uniformity (DSNU) and white spots. The algorithm works fully autonomous and adapts to e.g. increasing DSNU and up-coming white spots automatically without ground maintenance or re-calibration. In contrast to conventional correction methods the described algorithm does not need calibration data memory like full image sized calibration data sets. The application of the presented algorithm managing the typical APS detector error contributors is a key element for the design of star trackers for long term satellite applications like geostationary telecom platforms.

  15. Reliability and validity of ten consumer activity trackers.

    PubMed

    Kooiman, Thea J M; Dontje, Manon L; Sprenger, Siska R; Krijnen, Wim P; van der Schans, Cees P; de Groot, Martijn

    2015-01-01

    Activity trackers can potentially stimulate users to increase their physical activity behavior. The aim of this study was to examine the reliability and validity of ten consumer activity trackers for measuring step count in both laboratory and free-living conditions. Healthy adult volunteers (n = 33) walked twice on a treadmill (4.8 km/h) for 30 min while wearing ten different activity trackers (i.e. Lumoback, Fitbit Flex, Jawbone Up, Nike+ Fuelband SE, Misfit Shine, Withings Pulse, Fitbit Zip, Omron HJ-203, Yamax Digiwalker SW-200 and Moves mobile application). In free-living conditions, 56 volunteers wore the same activity trackers for one working day. Test-retest reliability was analyzed with the Intraclass Correlation Coefficient (ICC). Validity was evaluated by comparing each tracker with the gold standard (Optogait system for laboratory and ActivPAL for free-living conditions), using paired samples t-tests, mean absolute percentage errors, correlations and Bland-Altman plots. Test-retest analysis revealed high reliability for most trackers except for the Omron (ICC .14), Moves app (ICC .37) and Nike+ Fuelband (ICC .53). The mean absolute percentage errors of the trackers in laboratory and free-living conditions respectively, were: Lumoback (-0.2, -0.4), Fibit Flex (-5.7, 3.7), Jawbone Up (-1.0, 1.4), Nike+ Fuelband (-18, -24), Misfit Shine (0.2, 1.1), Withings Pulse (-0.5, -7.9), Fitbit Zip (-0.3, 1.2), Omron (2.5, -0.4), Digiwalker (-1.2, -5.9), and Moves app (9.6, -37.6). Bland-Altman plots demonstrated that the limits of agreement varied from 46 steps (Fitbit Zip) to 2422 steps (Nike+ Fuelband) in the laboratory condition, and 866 steps (Fitbit Zip) to 5150 steps (Moves app) in the free-living condition. The reliability and validity of most trackers for measuring step count is good. The Fitbit Zip is the most valid whereas the reliability and validity of the Nike+ Fuelband is low.

  16. Development of the FitSight Fitness Tracker to Increase Time Outdoors to Prevent Myopia.

    PubMed

    Verkicharla, Pavan K; Ramamurthy, Dharani; Nguyen, Quang Duc; Zhang, Xinquan; Pu, Suan-Hui; Malhotra, Rahul; Ostbye, Truls; Lamoureux, Ecosse L; Saw, Seang-Mei

    2017-06-01

    To develop a fitness tracker (FitSight) to encourage children to increase time spent outdoors. To evaluate the wear pattern for this tracker and outdoor time pattern by estimating light illumination levels among children. The development of the FitSight fitness tracker involved the designing of two components: (1) the smartwatch with custom-made FitSight watch application (app) to log the instant light illuminance levels the wearer is exposed to, and (2) a companion smartphone app that synchronizes the time outdoors recorded by the smartwatch to smartphone via Bluetooth communication. Smartwatch wear patterns and tracker-recorded daily light illuminance levels data were gathered over 7 days from 23 Singapore children (mean ± standard deviation age: 9.2 ± 1.4 years). Feedback about the tracker was obtained from 14 parents using a three-level rating scale: very poor/poor/good. Of the 14 parents, 93% rated the complete "FitSight fitness tracker" as good and 64% rated its wearability as good. While 61% of 23 children wore the watch on all study days (i.e., 0 nonwear days), 26% had 1 nonwear day, and 4.5% children each had 3, 4, and 5 nonwear days, respectively. On average, children spent approximately 1 hour in light levels greater than 1000 lux on weekdays and 1.3 hours on weekends (60 ± 46 vs. 79 ± 53 minutes, P = 0.19). Mean number of outdoor "spurts" (light illuminance levels >1000 lux) per day was 8 ± 3 spurts with spurt duration of 34 ± 32 minutes. The FitSight tracker with its novel features may motivate children to increase time outdoors and play an important role in supplementing community outdoor programs to prevent myopia. If the developed noninvasive, wearable, smartwatch-based fitness tracker, FitSight, promotes daytime outdoor activity among children, it will be beneficial in addressing the epidemic of myopia.

  17. Growth of farmed blue mussels ( Mytilus edulis L.) in a Norwegian coastal area; comparison of food proxies by DEB modeling

    NASA Astrophysics Data System (ADS)

    Handå, Aleksander; Alver, Morten; Edvardsen, Christian Vik; Halstensen, Stein; Olsen, Anders Johny; Øie, Gunvor; Reitan, Kjell Inge; Olsen, Yngvar; Reinertsen, Helge

    2011-11-01

    Seston variables and growth of the blue mussel ( Mytilus edulis L.) were measured during the growth season from March to October in three suspended longline farms in Central Norway; one in the inner part of Åfjorden (63° 56' N, 10° 11' E) and two in Inner and Outer Koet, respectively (63° 49' N, 9° 42' and 47' E). Four seston variables were used as alternative input values in a Dynamic Energy Budget (DEB) model to compare their suitability as food proxies for predicting mussel growth: 1; total particulate matter (TPM), 2; particulate organic matter (POM), 3; organic content (OC) and 4; chlorophyll a (chl a). Mean TPM and POM measured 6.1 and 1.9 mg L - 1 in Åfjorden, 10.3 and 4.2 mg L - 1 in Inner Koet, and 10.5 and 4.6 mg L - 1 in Outer Koet, respectively, resulting in a mean OC of 32, 41 and 44% in Åfjorden and Inner and Outer Koet, respectively. Mean chl a measured 1.6 μg L - 1 in Åfjorden, 3.1 μg L - 1 in Inner Koet, and 1.6 μg L - 1 in Outer Koet. Average length growth was 0.20% day - 1 in medium sized mussels (24-36 mm) in Åfjorden and 0.08% day - 1 in large mussels (40-55 mm) in Inner and Outer Koet. Mean standardized soft tissue dry weight ranged between 250 and 390 mg in Åfjorden, 600 and 1175 in Inner Koet, and 600 and 960 mg in Outer Koet, and showed a seasonal pattern independent of growth in length with scattered spawnings. The model showed the best match for a single criterion for growth in both length and soft tissue dry weight for different food proxies depending on location. TPM gave the best match in Åfjorden, while chl a and POM gave the best match in Inner and Outer Koet, respectively. For Åfjorden, growth in length decreased markedly at the end of the sampling period, and this decrease was not reproduced by the model for any of the food proxies. For Inner and Outer Koet, agreement between measured and modeled length was quite good for the optimal choices of food proxy, with clear variations between the proxies for both farms. The model fit the observed soft tissue dry weight well in Åfjorden and Outer Koet, while underestimating it in Inner Koet. The differences in fit between proxies were minor for Åfjorden and Outer Koet, while OC gave the best fit and chl a the poorest fit for Inner Koet. The results indicate that different food sources have different impact on growth at different locations. DEB modeling is a useful tool in comparing which proxies give the most relevant information.

  18. Compensation for Time-Dependent Star Tracker Thermal Deformation on the Aqua Spacecraft

    NASA Technical Reports Server (NTRS)

    Hashmall, Joseph A.; Natanson, Gregory; Glickman, Jonathan; Sedlak, Joseph

    2004-01-01

    Analysis of attitude sensor data from the Aqua mission showed small but systematic differences between batch least-squares and extended Kalman filter attitudes. These differences were also found to be correlated with star tracker residuals, gyro bias estimates, and star tracker baseplate temperatures. This paper describes the analysis that shows that these correlations are all consistent with a single cause: time-dependent thermal deformation of star tracker alignments. These varying alignments can be separated into relative and common components. The relative misalignments can be determined and compensated for. The common misalignments can only be determined in special cases.

  19. Users' experiences of wearable activity trackers: a cross-sectional study.

    PubMed

    Maher, Carol; Ryan, Jillian; Ambrosi, Christina; Edney, Sarah

    2017-11-15

    Wearable activity trackers offer considerable promise for helping users to adopt healthier lifestyles. This study aimed to explore users' experience of activity trackers, including usage patterns, sharing of data to social media, perceived behaviour change (physical activity, diet and sleep), and technical issues/barriers to use. A cross-sectional online survey was developed and administered to Australian adults who were current or former activity tracker users. Results were analysed descriptively, with differences between current and former users and wearable brands explored using independent samples t-tests, Mann-Whitney, and chi square tests. Participants included 200 current and 37 former activity tracker users (total N = 237) with a mean age of 33.1 years (SD 12.4, range 18-74 years). Fitbit (67.5%) and Garmin devices (16.5%) were most commonly reported. Participants typically used their trackers for sustained periods (5-7 months) and most intended to continue usage. Participants reported they had improved their physical activity (51-81%) more commonly than they had their diet (14-40%) or sleep (11-24%), and slightly more participants reported to value the real time feedback (89%) compared to the long-term monitoring (78%). Most users (70%) reported they had experienced functionality issues with their devices, most commonly related to battery life and technical difficulties. Results suggest users find activity trackers appealing and useful tools for increasing perceived physical activity levels over a sustained period.

  20. Analysis of the effects of Eye-Tracker performance on the pulse positioning errors during refractive surgery☆

    PubMed Central

    Arba-Mosquera, Samuel; Aslanides, Ioannis M.

    2012-01-01

    Purpose To analyze the effects of Eye-Tracker performance on the pulse positioning errors during refractive surgery. Methods A comprehensive model, which directly considers eye movements, including saccades, vestibular, optokinetic, vergence, and miniature, as well as, eye-tracker acquisition rate, eye-tracker latency time, scanner positioning time, laser firing rate, and laser trigger delay have been developed. Results Eye-tracker acquisition rates below 100 Hz correspond to pulse positioning errors above 1.5 mm. Eye-tracker latency times to about 15 ms correspond to pulse positioning errors of up to 3.5 mm. Scanner positioning times to about 9 ms correspond to pulse positioning errors of up to 2 mm. Laser firing rates faster than eye-tracker acquisition rates basically duplicate pulse-positioning errors. Laser trigger delays to about 300 μs have minor to no impact on pulse-positioning errors. Conclusions The proposed model can be used for comparison of laser systems used for ablation processes. Due to the pseudo-random nature of eye movements, positioning errors of single pulses are much larger than observed decentrations in the clinical settings. There is no single parameter that ‘alone’ minimizes the positioning error. It is the optimal combination of the several parameters that minimizes the error. The results of this analysis are important to understand the limitations of correcting very irregular ablation patterns.

  1. Collaborative engineering and design management for the Hobby-Eberly Telescope tracker upgrade

    NASA Astrophysics Data System (ADS)

    Mollison, Nicholas T.; Hayes, Richard J.; Good, John M.; Booth, John A.; Savage, Richard D.; Jackson, John R.; Rafal, Marc D.; Beno, Joseph H.

    2010-07-01

    The engineering and design of systems as complex as the Hobby-Eberly Telescope's* new tracker require that multiple tasks be executed in parallel and overlapping efforts. When the design of individual subsystems is distributed among multiple organizations, teams, and individuals, challenges can arise with respect to managing design productivity and coordinating successful collaborative exchanges. This paper focuses on design management issues and current practices for the tracker design portion of the Hobby-Eberly Telescope Wide Field Upgrade project. The scope of the tracker upgrade requires engineering contributions and input from numerous fields including optics, instrumentation, electromechanics, software controls engineering, and site-operations. Successful system-level integration of tracker subsystems and interfaces is critical to the telescope's ultimate performance in astronomical observation. Software and process controls for design information and workflow management have been implemented to assist the collaborative transfer of tracker design data. The tracker system architecture and selection of subsystem interfaces has also proven to be a determining factor in design task formulation and team communication needs. Interface controls and requirements change controls will be discussed, and critical team interactions are recounted (a group-participation Failure Modes and Effects Analysis [FMEA] is one of special interest). This paper will be of interest to engineers, designers, and managers engaging in multi-disciplinary and parallel engineering projects that require coordination among multiple individuals, teams, and organizations.

  2. How do the medial olivocochlear efferents influence the biomechanics of the outer hair cells and thereby the cochlear amplifier? Simulation results

    NASA Astrophysics Data System (ADS)

    Saremi, Amin; Stenfelt, Stefan; Verhulst, Sarah

    2015-12-01

    The bottom-up signal pathway, which starts from the outer ear and leads to the brain cortices, gives the classic image of the human sound perception. However, there have been growing evidences in the last six decades for existence of a functional descending network whereby the central auditory system can modulate the early auditory processing, in a top-down manner. The medial olivocochlear efferent fibers project from the superior olivary complex at the brainstem into the inner ear. They are linked to the basal poles of the hair cells by forming synaptic cisterns. This descending network can activate nicotinic cholinergic receptors (nAChR) that increase the membrane conductance of the outer hair cells and thereby modify the magnitude of the active force generated inside the cochlea. The aim of the presented work is to quantitatively investigate how the changes in the biomechanics of the outer hair cells, caused by the efferent activation, manipulate the cochlear responses. This is done by means of a frequency-domain biophysical model of the cochlea [12] where the parameters of the model convey physiological interpretations of the human cochlear structures. The simulations manifest that a doubling of the outer hair cell conductance, due to efferent activation, leads to a frequency-dependent gain reduction along the cochlear duct with its highest effect at frequencies between 1 kHz and 3.5 kHz and a maximum of approximately 10 dB gain reduction at 2 kHz. This amount of the gain inhibition and its frequency dependence reasonably agrees with the experimental data recorded from guinea pig, cat and human cochleae where the medial olivococlear efferents had been elicited by broad-band stimuli. The simulations also indicate that the efferent-induced increase of the outer hair cell conductance increases the best frequency of the cochlear responses, in the basal region. The presented simulations quantitatively confirm that activation of the medial olivocochlear efferents can biomechanically manipulate the cochlear responses, in a top-down manner, by inhibiting the gain of the cochlear amplifier as well as altering the frequency-position map (tuning pattern) of the cochlea.

  3. Bioorganic/inorganic hybrid composition of sponge spicules: matrix of the giant spicules and of the comitalia of the deep sea hexactinellid Monorhaphis.

    PubMed

    Müller, Werner E G; Wang, Xiaohong; Kropf, Klaus; Ushijima, Hiroshi; Geurtsen, Werner; Eckert, Carsten; Tahir, Muhammad Nawaz; Tremel, Wolfgang; Boreiko, Alexandra; Schlossmacher, Ute; Li, Jinhe; Schröder, Heinz C

    2008-02-01

    The giant basal spicules of the siliceous sponges Monorhaphis chuni and Monorhaphis intermedia (Hexactinellida) represent the largest biosilica structures on earth (up to 3m long). Here we describe the construction (lamellar organization) of these spicules and of the comitalia and highlight their organic matrix in order to understand their mechanical properties. The spicules display three distinct regions built of biosilica: (i) the outer lamellar zone (radius: >300 microm), (ii) the bulky axial cylinder (radius: <75 microm), and (iii) the central axial canal (diameter: <2 microm) with its organic axial filament. The spicules are loosely covered with a collagen net which is regularly perforated by 7-10 microm large holes; the net can be silicified. The silica layers forming the lamellar zone are approximately 5 microm thick; the central axial cylinder appears to be composed of almost solid silica which becomes porous after etching with hydrofluoric acid (HF). Dissolution of a complete spicule discloses its complex structure with distinct lamellae in the outer zone (lamellar coating) and a more resistant central part (axial barrel). Rapidly after the release of the organic coating from the lamellar zone the protein layers disintegrate to form irregular clumps/aggregates. In contrast, the proteinaceous axial barrel, hidden in the siliceous axial cylinder, is set up by rope-like filaments. Biochemical analysis revealed that the (dominant) molecule of the lamellar coating is a 27-kDa protein which displays catalytic, proteolytic activity. High resolution electron microscopic analysis showed that this protein is arranged within the lamellae and stabilizes these surfaces by palisade-like pillars. The mechanical behavior of the spicules was analyzed by a 3-point bending assay, coupled with scanning electron microscopy. The load-extension curve of the spicule shows a biphasic breakage/cracking pattern. The outer lamellar zone cracks in several distinct steps showing high resistance in concert with comparably low elasticity, while the axial cylinder breaks with high elasticity and lower stiffness. The complex bioorganic/inorganic hybrid composition and structure of the Monorhaphis spicules might provide the blueprint for the synthesis of bio-inspired material, with unusual mechanical properties (strength, stiffness) without losing the exceptional properties of optical transmission.

  4. SU-F-18C-11: Diameter Dependency of the Radial Dose Distribution in a Long Polyethylene Cylinder

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

    Bakalyar, D; McKenney, S; Feng, W

    Purpose: The radial dose distribution in the central plane of a long cylinder following a long CT scan depends upon the diameter and composition of the cylinder. An understanding of this behavior is required for determining the spatial average of the dose in the central plane. Polyethylene, the material for construction of the TG200/ICRU phantom (30 cm in diameter) was used for this study. Size effects are germane to the principles incorporated in size specific dose estimates (SSDE); thus diameter dependency was explored as well. Method: ssuming a uniform cylinder and cylindrically symmetric conditions of irradiation, the dose distribution canmore » be described using a radial function. This function must be an even function of the radial distance due to the conditions of symmetry. Two effects are accounted for: The direct beam makes its weakest contribution at the center while the contribution due to scatter is strongest at the center and drops off abruptly at the outer radius. An analytic function incorporating these features was fit to Monte Carlo results determined for infinite polyethylene cylinders of various diameters. A further feature of this function is that it is integrable. Results: Symmetry and continuity dictate a local extremum at the center which is a minimum for the larger sizes. The competing effects described above can Resultin an absolute maximum occurring between the center and outer edge of the cylinders. For the smallest cylinders, the maximum dose may occur at the center. Conclusion: An integrable, analytic function can be used to characterize the radial dependency of dose for cylindrical CT phantoms of various sizes. One use for this is to help determine average dose distribution over the central cylinder plane when equilibrium dose has been reached.« less

  5. The nuclear activity and central structure of the elliptical galaxy NGC 5322

    NASA Astrophysics Data System (ADS)

    Dullo, Bililign T.; Knapen, Johan H.; Williams, David R. A.; Beswick, Robert J.; Bendo, George; Baldi, Ranieri D.; Argo, Megan; McHardy, Ian M.; Muxlow, Tom; Westcott, J.

    2018-04-01

    We have analysed a new high-resolution e-MERLIN 1.5 GHz radio continuum map together with HST and SDSS imaging of NGC 5322, an elliptical galaxy hosting radio jets, aiming to understand the galaxy's central structure and its connection to the nuclear activity. We decomposed the composite HST + SDSS surface brightness profile of the galaxy into an inner stellar disc, a spheroid, and an outer stellar halo. Past works showed that this embedded disc counter-rotates rapidly with respect to the spheroid. The HST images reveal an edge-on nuclear dust disc across the centre, aligned along the major-axis of the galaxy and nearly perpendicular to the radio jets. After careful masking of this dust disc, we find a central stellar mass deficit Mdef in the spheroid, scoured by SMBH binaries with final mass MBH such that Mdef/MBH ˜ 1.3-3.4. We propose a three-phase formation scenario for NGC 5322, where a few (2-7) `dry' major mergers involving SMBHs built the spheroid with a depleted core. The cannibalism of a gas-rich satellite subsequently creates the faint counter-rotating disc and funnels gaseous material directly on to the AGN, powering the radio core with a brightness temperature of TB, core ˜ 4.5 × 107 K and the low-power radio jets (Pjets ˜ 7.04 × 1020 W Hz-1), which extend ˜1.6 kpc. The outer halo can later grow via minor mergers and the accretion of tidal debris. The low-luminosity AGN/jet-driven feedback may have quenched the late-time nuclear star formation promptly, which could otherwise have replenished the depleted core.

  6. Differences in Aqueous Concentrations of Cytokines in Macular Edema Secondary to Branch and Central Retinal Vein Occlusion

    PubMed Central

    Feng, Jing; Zhao, Tong; Zhang, Yan; Ma, Yan; Jiang, Yanrong

    2013-01-01

    Purpose This study investigates the differential aqueous concentrations of interleukin 6, 8, 1β (IL-6, IL-8, IL-1β, respectively), serum amyloid A (SAA), transforming growth factor (TGF)-β, basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) in eyes with macular edema as a result of a branch retinal vein occlusion (BRVO) or central retinal vein occlusion (CRVO). Principal Findings Significantly higher concentrations of IL-6, IL-8, IL-1β, TGF-β, bFGF, SAA, and VEGF were found in the aqueous humor of CRVO and BRVO patients than in the aqueous humor of control patients. A significant correlation was observed between the concentration of bFGF and the inner central macular thickness (CMT) of BRVO patients (r = 0.688; P = 0.02). A significant correlation was observed between the concentration of SAA and both the full and outer CMT of the ischemic group (r = 0.545 and 0.683, respectively; P = 0.04 and 0.01, respectively). In the non-ischemic group, the level of IL-6 was significantly associated with inner CMT (r = 0.560; P = 0.03). The full and outer CMT was significantly reduced in CRVO patients when compared with BRVO patients (P = 0.02 and 0.02, respectively) after injection of intravitreal bevacizumab (IVB) at 4 weeks. Significance Serum amyloid A as a major protein involved in the acute and chronic stages of inflammation, and IL-6 and bFGF were significantly associated with the extent of macular edema in patients with RVO. Besides VEGF, other inflammatory cytokines and angiogenesic factors may be associated with RVO. This finding may have implications for the medical treatment of RVO. PMID:23861862

  7. A Circumstellar Disk around HD 169142 in the Mid-Infrared (N-Band)

    NASA Astrophysics Data System (ADS)

    Okamoto, Yoshiko Kataza; Kataza, Hirokazu; Honda, M.; Yamashita, T.; Fujiyoshi, T.; Miyata, T.; Sako, S.; Fujiwara, H.; Sakon, I.; Fukagawa, M.; Momose, M.; Onaka, T.

    2017-07-01

    The Herbig Ae star HD 169142 is one of the objects that show complex structure, such as multiple (innermost, middle, and outer) disks, gaps, and unresolved sources. We made N-band (8-13 μm) observations of HD 169142 with the Cooled Mid-Infrared Camera and Spectrometer on the 8.2 m Subaru Telescope. The images are spatially resolved out to an ˜1″ radius in all the observed bands. We made a simple disk model composed of an unresolved central source (representing the innermost disk/halo) and the ring at a radius r ˜ 25 au (corresponding to the inner wall or edge of a middle disk at ˜25-40 au). The radial intensity profile within the central region (≲0.″3 or ≲ 40 au) is well reproduced by the model. Furthermore, we subtracted the model image from the observed one to search for additional structures. In the model-subtracted images, we found an unresolved west source separated by 17.0 ± 2.9 au in the direction of position angle 260° ± 5° from the original emission peak, which is supposed to correspond to the position of the central star, and a bright east arc located at r ˜ 60 au. The west source is different from the L‧-band unresolved source recently found in coronagraphic observations. It could be a structure related to planet formation in the disk, such as a circumplanetary disk or clumpy disk structure. The east arc corresponds to the inner wall or edge of the outer disk. Based on data collected at the Subaru Telescope, which is operated by the National Astronomical Observatory of Japan.

  8. Poor Prognosis of Lower Inner Quadrant in Lymph Node-negative Breast Cancer Patients Who Received No Chemotherapy: A Study Based on Nationwide Korean Breast Cancer Registry Database.

    PubMed

    Hwang, Ki-Tae; Kim, Jongjin; Kim, Eun-Kyu; Jung, Sung Hoo; Sohn, Guiyun; Kim, Seung Il; Jeong, Joon; Lee, Hyouk Jin; Park, Jin Hyun; Oh, Sohee

    2017-07-01

    We aimed to investigate the prognostic influence of primary tumor site on the survival of patients with breast cancer. Data of 63,388 patients with primary breast cancer from the Korean Breast Cancer Registry were analyzed. Primary tumor sites were classified into 5 groups: upper outer quadrant, lower outer quadrant, upper inner quadrant, lower inner quadrant (LIQ), and central portion. We analyzed overall survival (OS) and breast cancer-specific survival (BCSS) according to primary tumor site. Central portion and LIQ showed lower survival rates regarding both OS and BCSS compared with the other 3 quadrants (all P < .05) and hazard ratios were 1.267 (95% CI, 1.180-1.360, P < .001) and 1.215 (95% CI, 1.097-1.345, P < .001), respectively. Although central portion showed more unfavorable clinicopathologic features, LIQ showed more favorable features than the other 3 quadrants. Primary tumor site was a significant factor in univariate and multivariate analyses for OS and BCSS (all P < .001). For lymph node-negative patients, LIQ showed a worse OS than the other primary tumor sites in the subgroup with no chemotherapy (P < .001), but that effect disappeared in the subgroup with chemotherapy (P = .058). LIQ showed a worse prognosis despite having more favorable clinicopathologic features than other tumor locations and it was more prominent for lymph node-negative patients who received no chemotherapy. The hypothesis of possible hidden internal mammary node metastasis could be suggested to play a key role in LIQ lesions. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. SDSS IV MaNGA - metallicity and nitrogen abundance gradients in local galaxies

    NASA Astrophysics Data System (ADS)

    Belfiore, Francesco; Maiolino, Roberto; Tremonti, Christy; Sánchez, Sebastian F.; Bundy, Kevin; Bershady, Matthew; Westfall, Kyle; Lin, Lihwai; Drory, Niv; Boquien, Médéric; Thomas, Daniel; Brinkmann, Jonathan

    2017-07-01

    We study the gas phase metallicity (O/H) and nitrogen abundance gradients traced by star-forming regions in a representative sample of 550 nearby galaxies in the stellar mass range 109-1011.5 M⊙ with resolved spectroscopic data from the Sloan Digital Sky Survey IV Mapping Nearby Galaxies at Apache Point Observatory survey. Using strong-line ratio diagnostics (R23 and O3N2 for metallicity and N2O2 for N/O) and referencing to the effective (half-light) radius (Re), we find that the metallicity gradient steepens with stellar mass, lying roughly flat among galaxies with log (M⋆/M⊙) = 9.0 but exhibiting slopes as steep as -0.14 dex R_e^{-1} at log (M⋆/M⊙) = 10.5 (using R23, but equivalent results are obtained using O3N2). At higher masses, these slopes remain typical in the outer regions of our sample (R > 1.5Re), but a flattening is observed in the central regions (R < 1Re). In the outer regions (R > 2.0Re), we detect a mild flattening of the metallicity gradient in stacked profiles, although with low significance. The N/O ratio gradient provides complementary constraints on the average chemical enrichment history. Unlike the oxygen abundance, the average N/O profiles do not flatten out in the central regions of massive galaxies. The metallicity and N/O profiles both depart significantly from an exponential form, suggesting a disconnect between chemical enrichment and stellar mass surface density on local scales. In the context of inside-out growth of discs, our findings suggest that central regions of massive galaxies today have evolved to an equilibrium metallicity, while the nitrogen abundance continues to increase as a consequence of delayed secondary nucleosynthetic production.

  10. New insights into the outflows from R Aquarii

    NASA Astrophysics Data System (ADS)

    Liimets, T.; Corradi, R. L. M.; Jones, D.; Verro, K.; Santander-García, M.; Kolka, I.; Sidonio, M.; Kankare, E.; Kankare, J.; Pursimo, T.; Wilson, P. A.

    2018-05-01

    Context. The source R Aquarii is a symbiotic binary surrounded by a large and complex nebula with a prominent curved jet. It is one of the closest known symbiotic systems, and therefore offers a unique opportunity to study the central regions of these systems and the formation and evolution of astrophysical jets. Aims: We aim to study the evolution of the central jet and outer nebula of R Aqr, taking advantage of a long term monitoring campaign of optical imaging, as well as of high-resolution integral field spectroscopy. Methods: Narrow-band images acquired over a period of more than 21 yr were compared in order to study the expansion and evolution of all components of the R Aqr nebula. The magnification method was used to derive the kinematic ages of the features that appear to expand radially. Integral field spectroscopy of the [O III] 5007 Å emission is used to study the velocity structure of the central regions of the jet. Results: New extended features, further out than the previously known hourglass nebula, are detected. The kinematic distance to R Aqr is calculated to be 178 pc using the expansion of the large hourglass nebula. This nebula of R Aqr is found to be roughly 650 yr old, while the inner regions have ages ranging from 125 to 290 yr. The outer nebula is found to be well described by a ballistic expansion, while for most components of the jet strong deviations from such behaviour are found. We find that the northern jet is mostly red-shifted while its southern part is blue-shifted, apparently at odds with findings from previous studies but almost certainly a consequence of the complex nature of the jet and variations in ionisation and illumination between observations.

  11. Hubble Finds a Little Gem

    NASA Image and Video Library

    2015-08-07

    This colorful bubble is a planetary nebula called NGC 6818, also known as the Little Gem Nebula. It is located in the constellation of Sagittarius (The Archer), roughly 6,000 light-years away from us. The rich glow of the cloud is just over half a light-year across — humongous compared to its tiny central star — but still a little gem on a cosmic scale. When stars like the sun enter "retirement," they shed their outer layers into space to create glowing clouds of gas called planetary nebulae. This ejection of mass is uneven, and planetary nebulae can have very complex shapes. NGC 6818 shows knotty filament-like structures and distinct layers of material, with a bright and enclosed central bubble surrounded by a larger, more diffuse cloud. Scientists believe that the stellar wind from the central star propels the outflowing material, sculpting the elongated shape of NGC 6818. As this fast wind smashes through the slower-moving cloud it creates particularly bright blowouts at the bubble’s outer layers. Hubble previously imaged this nebula back in 1997 with its Wide Field Planetary Camera 2, using a mix of filters that highlighted emission from ionized oxygen and hydrogen. This image, while from the same camera, uses different filters to reveal a different view of the nebula. Image credit: ESA/Hubble & NASA, Acknowledgement: Judy Schmidt NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  12. User Acceptance of Wrist-Worn Activity Trackers Among Community-Dwelling Older Adults: Mixed Method Study

    PubMed Central

    Puri, Arjun; Kim, Ben; Nguyen, Olivier; Stolee, Paul; Tung, James

    2017-01-01

    Background Wearable activity trackers are newly emerging technologies with the anticipation for successfully supporting aging-in-place. Consumer-grade wearable activity trackers are increasingly ubiquitous in the market, but the attitudes toward, as well as acceptance and voluntary use of, these trackers in older population are poorly understood. Objective The aim of this study was to assess acceptance and usage of wearable activity trackers in Canadian community-dwelling older adults, using the potentially influential factors as identified in literature and technology acceptance model. Methods A mixed methods design was used. A total of 20 older adults aged 55 years and older were recruited from Southwestern Ontario. Participants used 2 different wearable activity trackers (Xiaomi Mi Band and Microsoft Band) separately for each segment in the crossover design study for 21 days (ie, 42 days total). A questionnaire was developed to capture acceptance and experience at the end of each segment, representing 2 different devices. Semistructured interviews were conducted with 4 participants, and a content analysis was performed. Results Participants ranged in age from 55 years to 84 years (mean age: 64 years). The Mi Band gained higher levels of acceptance (16/20, 80%) compared with the Microsoft Band (10/20, 50%). The equipment characteristics dimension scored significantly higher for the Mi Band (P<.05). The amount a participant was willing to pay for the device was highly associated with technology acceptance (P<.05). Multivariate logistic regression with 3 covariates resulted in an area under the curve of 0.79. Content analysis resulted in the formation of the following main themes: (1) smartphones as facilitators of wearable activity trackers; (2) privacy is less of a concern for wearable activity trackers, (3) value proposition: self-awareness and motivation; (4) subjective norm, social support, and sense of independence; and (5) equipment characteristics matter: display, battery, comfort, and aesthetics. Conclusions Older adults were mostly accepting of wearable activity trackers, and they had a clear understanding of its value for their lives. Wearable activity trackers were uniquely considered more personal than other types of technologies, thereby the equipment characteristics including comfort, aesthetics, and price had a significant impact on the acceptance. Results indicated that privacy was less of concern for older adults, but it may have stemmed from a lack of understanding of the privacy risks and implications. These findings add to emerging research that investigates acceptance and factors that may influence acceptance of wearable activity trackers among older adults. PMID:29141837

  13. Cross modality registration of video and magnetic tracker data for 3D appearance and structure modeling

    NASA Astrophysics Data System (ADS)

    Sargent, Dusty; Chen, Chao-I.; Wang, Yuan-Fang

    2010-02-01

    The paper reports a fully-automated, cross-modality sensor data registration scheme between video and magnetic tracker data. This registration scheme is intended for use in computerized imaging systems to model the appearance, structure, and dimension of human anatomy in three dimensions (3D) from endoscopic videos, particularly colonoscopic videos, for cancer research and clinical practices. The proposed cross-modality calibration procedure operates this way: Before a colonoscopic procedure, the surgeon inserts a magnetic tracker into the working channel of the endoscope or otherwise fixes the tracker's position on the scope. The surgeon then maneuvers the scope-tracker assembly to view a checkerboard calibration pattern from a few different viewpoints for a few seconds. The calibration procedure is then completed, and the relative pose (translation and rotation) between the reference frames of the magnetic tracker and the scope is determined. During the colonoscopic procedure, the readings from the magnetic tracker are used to automatically deduce the pose (both position and orientation) of the scope's reference frame over time, without complicated image analysis. Knowing the scope movement over time then allows us to infer the 3D appearance and structure of the organs and tissues in the scene. While there are other well-established mechanisms for inferring the movement of the camera (scope) from images, they are often sensitive to mistakes in image analysis, error accumulation, and structure deformation. The proposed method using a magnetic tracker to establish the camera motion parameters thus provides a robust and efficient alternative for 3D model construction. Furthermore, the calibration procedure does not require special training nor use expensive calibration equipment (except for a camera calibration pattern-a checkerboard pattern-that can be printed on any laser or inkjet printer).

  14. Development and evaluation of a hand tracker using depth images captured from an overhead perspective.

    PubMed

    Czarnuch, Stephen; Mihailidis, Alex

    2015-03-27

    We present the development and evaluation of a robust hand tracker based on single overhead depth images for use in the COACH, an assistive technology for people with dementia. The new hand tracker was designed to overcome limitations experienced by the COACH in previous clinical trials. We train a random decision forest classifier using ∼5000 manually labeled, unbalanced, training images. Hand positions from the classifier are translated into task actions based on proximity to environmental objects. Tracker performance is evaluated using a large set of ∼24 000 manually labeled images captured from 41 participants in a fully-functional washroom, and compared to the system's previous colour-based hand tracker. Precision and recall were 0.994 and 0.938 for the depth tracker compared to 0.981 and 0.822 for the colour tracker with the current data, and 0.989 and 0.466 in the previous study. The improved tracking performance supports integration of the depth-based tracker into the COACH toward unsupervised, real-world trials. Implications for Rehabilitation The COACH is an intelligent assistive technology that can enable people with cognitive disabilities to stay at home longer, supporting the concept of aging-in-place. Automated prompting systems, a type of intelligent assistive technology, can help to support the independent completion of activities of daily living, increasing the independence of people with cognitive disabilities while reducing the burden of care experienced by caregivers. Robust motion tracking using depth imaging supports the development of intelligent assistive technologies like the COACH. Robust motion tracking also has application to other forms of assistive technologies including gaming, human-computer interaction and automated assessments.

  15. Behavior Change Techniques Present in Wearable Activity Trackers: A Critical Analysis

    PubMed Central

    Mercer, Kathryn; Li, Melissa; Giangregorio, Lora; Burns, Catherine

    2016-01-01

    Background Wearable activity trackers are promising as interventions that offer guidance and support for increasing physical activity and health-focused tracking. Most adults do not meet their recommended daily activity guidelines, and wearable fitness trackers are increasingly cited as having great potential to improve the physical activity levels of adults. Objective The objective of this study was to use the Coventry, Aberdeen, and London-Refined (CALO-RE) taxonomy to examine if the design of wearable activity trackers incorporates behavior change techniques (BCTs). A secondary objective was to critically analyze whether the BCTs present relate to known drivers of behavior change, such as self-efficacy, with the intention of extending applicability to older adults in addition to the overall population. Methods Wearing each device for a period of 1 week, two independent raters used CALO-RE taxonomy to code the BCTs of the seven wearable activity trackers available in Canada as of March 2014. These included Fitbit Flex, Misfit Shine, Withings Pulse, Jawbone UP24, Spark Activity Tracker by SparkPeople, Nike+ FuelBand SE, and Polar Loop. We calculated interrater reliability using Cohen's kappa. Results The average number of BCTs identified was 16.3/40. Withings Pulse had the highest number of BCTs and Misfit Shine had the lowest. Most techniques centered around self-monitoring and self-regulation, all of which have been associated with improved physical activity in older adults. Techniques related to planning and providing instructions were scarce. Conclusions Overall, wearable activity trackers contain several BCTs that have been shown to increase physical activity in older adults. Although more research and development must be done to fully understand the potential of wearables as health interventions, the current wearable trackers offer significant potential with regard to BCTs relevant to uptake by all populations, including older adults. PMID:27122452

  16. Behavior Change Techniques Present in Wearable Activity Trackers: A Critical Analysis.

    PubMed

    Mercer, Kathryn; Li, Melissa; Giangregorio, Lora; Burns, Catherine; Grindrod, Kelly

    2016-04-27

    Wearable activity trackers are promising as interventions that offer guidance and support for increasing physical activity and health-focused tracking. Most adults do not meet their recommended daily activity guidelines, and wearable fitness trackers are increasingly cited as having great potential to improve the physical activity levels of adults. The objective of this study was to use the Coventry, Aberdeen, and London-Refined (CALO-RE) taxonomy to examine if the design of wearable activity trackers incorporates behavior change techniques (BCTs). A secondary objective was to critically analyze whether the BCTs present relate to known drivers of behavior change, such as self-efficacy, with the intention of extending applicability to older adults in addition to the overall population. Wearing each device for a period of 1 week, two independent raters used CALO-RE taxonomy to code the BCTs of the seven wearable activity trackers available in Canada as of March 2014. These included Fitbit Flex, Misfit Shine, Withings Pulse, Jawbone UP24, Spark Activity Tracker by SparkPeople, Nike+ FuelBand SE, and Polar Loop. We calculated interrater reliability using Cohen's kappa. The average number of BCTs identified was 16.3/40. Withings Pulse had the highest number of BCTs and Misfit Shine had the lowest. Most techniques centered around self-monitoring and self-regulation, all of which have been associated with improved physical activity in older adults. Techniques related to planning and providing instructions were scarce. Overall, wearable activity trackers contain several BCTs that have been shown to increase physical activity in older adults. Although more research and development must be done to fully understand the potential of wearables as health interventions, the current wearable trackers offer significant potential with regard to BCTs relevant to uptake by all populations, including older adults.

  17. Predictive value of spectral-domain optical coherence tomography features in assessment of visual prognosis in eyes with acute welding arc maculopathy.

    PubMed

    Zhang, Chunxia; Dang, Guangfu; Zhao, Tianmei; Wang, DongLin; Su, Yan; Qu, Yi

    2018-04-12

    To observe spectral-domain optical coherence tomography (SD-OCT) features and to determine whether baseline OCT features can be used as predictors of visual acuity outcome in eyes with acute welding arc maculopathy. This retrospective study enrolled twenty-two eyes of eleven subjects with acute welding arc maculopathy. All subjects were evaluated by SD-OCT at baseline and final visit. The involved parameters included best-corrected visual acuity (BCVA), central macular thickness (CMT), the length of ellipsoid zone (EZ) defects, the greatest linear dimension (GLD) of outer retinal lesions, EZ reflectivity and relative EZ reflectivity (defined as the ratio of EZ reflectivity to retinal pigment epithelium reflectivity on OCT). Acute welding arc maculopathy was presented as abnormal hyperreflectivity, hyporeflectivity and defects of outer retinal layer in fovea on OCT. Compared with baseline, BCVA improved significantly accompanied by decreased GLD of outer retinal lesions and the length of EZ defects at final visit (P = 0.0004, P < 0.0001 and P < 0.0001, respectively). No significant changes were shown on CMT (P = 0.248). In multivariate regression analysis, final BCVA was associated with baseline BCVA and the length of EZ defects (P = 0.012 and P = 0.045, respectively). However, EZ reflectivity and relative EZ reflectivity were not associated with final BCVA (P > 0.05). In conclusion, SD-OCT images clearly reveal morphological changes in outer retinal layer in acute welding arc maculopathy. The baseline BCVA and length of EZ defects are the strongest predictors of final BCVA.

  18. Formation of a White-Light Jet Within a Quadrupolar Magnetic Configuration

    NASA Astrophysics Data System (ADS)

    Filippov, Boris; Koutchmy, Serge; Tavabi, Ehsan

    2013-08-01

    We analyze multi-wavelength and multi-viewpoint observations of a large-scale event viewed on 7 April 2011, originating from an active-region complex. The activity leads to a white-light jet being formed in the outer corona. The topology and evolution of the coronal structures were imaged in high resolution using the Atmospheric Imaging Assembly (AIA) onboard the Solar Dynamics Observatory (SDO). In addition, large field-of-view images of the corona were obtained using the Sun Watcher using Active Pixel System detector and Image Processing (SWAP) telescope onboard the PRoject for Onboard Autonomy (PROBA2) microsatellite, providing evidence for the connectivity of the coronal structures with outer coronal features that were imaged with the Large Angle Spectrometric Coronagraph (LASCO) C2 on the S olar and Heliospheric Observatory (SOHO). The data sets reveal an Eiffel-tower type jet configuration extending into a narrow jet in the outer corona. The event starts from the growth of a dark area in the central part of the structure. The darkening was also observed in projection on the disk by the Solar TErrestrial RElations Observatory-Ahead (STEREO-A) spacecraft from a different point of view. We assume that the dark volume in the corona descends from a coronal cavity of a flux rope that moved up higher in the corona but still failed to erupt. The quadrupolar magnetic configuration corresponds to a saddle-like shape of the dark volume and provides a possibility for the plasma to escape along the open field lines into the outer corona, forming the white-light jet.

  19. Geochemistry and magnetic sediment distribution at the western boundary upwelling system of southwest Atlantic

    NASA Astrophysics Data System (ADS)

    Cruz, Anna P. S.; Barbosa, Catia F.; Ayres-Neto, Arthur; Munayco, Pablo; Scorzelli, Rosa B.; Amorim, Nívea Santos; Albuquerque, Ana L. S.; Seoane, José C. S.

    2018-02-01

    In order to investigate the chemical and magnetic characteristics of sediments of the western boundary upwelling system of Southwest Atlantic we analyzed magnetic susceptibility, grain size distribution, total organic carbon, heavy mineral abundance, Fe associated with Mössbauer spectra, and Fe and Mn of pore water to evaluate the deposition patterns of sediments. Four box-cores were collected along a cross-shelf transect. Brazil Current and coastal plume exert a primary control at the inner and outer shelf cores, which exhibited similar depositional patterns characterized by a high abundance of heavy minerals (mean 0.21% and 0.08%, respectively) and very fine sand, whereas middle shelf cores presented low abundances of heavy minerals (mean 0.03%) and medium silt. The inner shelf was dominated by sub-angular grains, while in middle and outer shelf cores well-rounded grains were found. The increasing Fe3+:Fe2+ ratio from the inner to the outer shelf reflects farther distance to the sediment source. The outer shelf presented well-rounded minerals, indicating abrasive processes as a result of transport by the Brazil Current from the source areas. In the middle shelf, cold-water intrusion of the South Atlantic Central Water contributes to the primary productivity, resulting in higher deposition of fine sediment and organic carbon accumulation. The high input of organic carbon and the decreased grain size are indicative of changes in the hydrodynamics and primary productivity fueled by the western boundary upwelling system, which promotes loss of magnetization due to the induction of diagenesis of iron oxide minerals.

  20. Signatures of Young Planets in the Continuum Emission from Protostellar Disks

    NASA Astrophysics Data System (ADS)

    Isella, Andrea; Turner, Neal J.

    2018-06-01

    Many protostellar disks show central cavities, rings, or spiral arms likely caused by low-mass stellar or planetary companions, yet few such features are conclusively tied to bodies embedded in the disks. We note that even small features on the disk surface cast shadows, because the starlight grazes the surface. We therefore focus on accurately computing the disk thickness, which depends on its temperature. We present models with temperatures set by the balance between starlight heating and radiative cooling, which are also in vertical hydrostatic equilibrium. The planet has 20, 100, or 1000 M ⊕, ranging from barely enough to perturb the disk significantly, to clearing a deep tidal gap. The hydrostatic balance strikingly alters the appearance of the model disk. The outer walls of the planet-carved gap puff up under starlight heating, throwing a shadow across the disk beyond. The shadow appears in scattered light as a dark ring that could be mistaken for a gap opened by another more distant planet. The surface brightness contrast between outer wall and shadow for the 1000 M ⊕ planet is an order of magnitude greater than a model neglecting the temperature disturbances. The shadow is so deep that it largely hides the planet-launched outer arm of the spiral wave. Temperature gradients are such that outer low-mass planets undergoing orbital migration will converge within the shadow. Furthermore, the temperature perturbations affect the shape, size, and contrast of features at millimeter and centimeter wavelengths. Thus radiative heating and cooling are key to the appearance of protostellar disks with embedded planets.

  1. Cranial airways and the integration between the inner and outer facial skeleton in humans.

    PubMed

    Bastir, Markus; Rosas, Antonio

    2013-10-01

    The cranial airways are in the center of the human face. Therefore variation in the size and shape of these central craniofacial structures could have important consequences for the surrounding midfacial morphology during development and evolution. Yet such interactions are unclear because one school of thought, based on experimental and developmental evidence, suggests a relative independence (modularity) of these two facial compartments, whereas another one assumes tight morphological integration. This study uses geometric morphometrics of modern humans (N = 263) and 40 three-dimensional-landmarks of the skeletal nasopharynx and nasal cavity and outer midfacial skeleton to analyze these questions in terms of modularity. The sizes of all facial compartments were all strongly correlated. Shape integration was high between the cranial airways and the outer midfacial skeleton and between the latter and the anterior airway openings (skeletal regions close to and including piriform aperture). However, no shape integration was detected between outer midface and posterior airway openings (nasopharynx and choanae). Similarly, no integration was detected between posterior and anterior airway openings. This may reflect functional modularization of nasal cavity compartments related to respiratory physiology and differential developmental interactions with the face. Airway size likely relates to the energetics of the organism, whereas airways shape might be more indicative of respiratory physiology and climate. Although this hypothesis should be addressed in future steps, here we suggest that selection on morphofunctional characteristics of the cranial airways could have cascading effects for the variation, development, and evolution of the human face. Copyright © 2013 Wiley Periodicals, Inc.

  2. Identification of g-Modes in a Sun with Mixed Core

    NASA Technical Reports Server (NTRS)

    Wolff, Charles L.

    2008-01-01

    The elusive g-mode oscillations mainly operate deep inside the Sun where the nuclear fires burn. They can modify the Sun's output on a cadence of months and years when coupled into groups. Scientists have failed to detect their oscillation periods because they were looking for periods much too short. This paper shows that if g-modes slowly mix the central 16% of the Sun on a million year time scale or less, then g-mode periods become two and a half times longer. These longer periods are identified in existing data from the orbiting GOLF and SOH0 experiments. This opens the door to measuring the Sun's central regions with g-modes just as helioseismology has used sound waves to probe its outer half.

  3. IMM tracking of a theater ballistic missile during boost phase

    NASA Astrophysics Data System (ADS)

    Hutchins, Robert G.; San Jose, Anthony

    1998-09-01

    Since the SCUD launches in the Gulf War, theater ballistic missile (TBM) systems have become a growing concern for the US military. Detection, tracking and engagement during boost phase or shortly after booster cutoff are goals that grow in importance with the proliferation of weapons of mass destruction. This paper addresses the performance of tracking algorithms for TBMs during boost phase and across the transition to ballistic flight. Three families of tracking algorithms are examined: alpha-beta-gamma trackers, Kalman-based trackers, and the interactive multiple model (IMM) tracker. In addition, a variation on the IMM to include prior knowledge of a booster cutoff parameter is examined. Simulated data is used to compare algorithms. Also, the IMM tracker is run on an actual ballistic missile trajectory. Results indicate that IMM trackers show significant advantage in tracking through the model transition represented by booster cutoff.

  4. Robust object tacking based on self-adaptive search area

    NASA Astrophysics Data System (ADS)

    Dong, Taihang; Zhong, Sheng

    2018-02-01

    Discriminative correlation filter (DCF) based trackers have recently achieved excellent performance with great computational efficiency. However, DCF based trackers suffer boundary effects, which result in the unstable performance in challenging situations exhibiting fast motion. In this paper, we propose a novel method to mitigate this side-effect in DCF based trackers. We change the search area according to the prediction of target motion. When the object moves fast, broad search area could alleviate boundary effects and reserve the probability of locating object. When the object moves slowly, narrow search area could prevent effect of useless background information and improve computational efficiency to attain real-time performance. This strategy can impressively soothe boundary effects in situations exhibiting fast motion and motion blur, and it can be used in almost all DCF based trackers. The experiments on OTB benchmark show that the proposed framework improves the performance compared with the baseline trackers.

  5. Sign-tracking predicts increased choice of cocaine over food in rats.

    PubMed

    Tunstall, Brendan J; Kearns, David N

    2015-03-15

    The purpose of this study was to determine whether the tendency to sign-track to a food cue was predictive of rats' choice of cocaine over food. First, rats were trained on a procedure where insertion of a retractable lever was paired with food. A sub-group of rats - sign-trackers - primarily approached and contacted the lever, while another sub-group - goal-trackers - approached the site of food delivery. Rats were then trained on a choice task where they could choose between an infusion of cocaine (1.0 mg/kg) and a food pellet (45 mg). Sign-trackers chose cocaine over food significantly more often than did goal-trackers. These results support the incentive-salience theory of addiction and add to a growing number of studies which suggest that sign-trackers may model an addiction-prone phenotype. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Mechanical stability of the CMS strip tracker measured with a laser alignment system

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

    Sirunyan, A. M.; Tumasyan, A.; Adam, W.

    Here, the CMS tracker consists of 206 m 2 of silicon strip sensors assembled on carbon fibre composite structures and is designed for operation in the temperature range from –25 to +25°C. The mechanical stability of tracker components during physics operation was monitored with a few μm resolution using a dedicated laser alignment system as well as particle tracks from cosmic rays and hadron-hadron collisions. During the LHC operational period of 2011–2013 at stable temperatures, the components of the tracker were observed to experience relative movements of less than 30μm. In addition, temperature variations were found to cause displacements ofmore » tracker structures of about 2μm°C, which largely revert to their initial positions when the temperature is restored to its original value.« less

  7. Mechanical stability of the CMS strip tracker measured with a laser alignment system

    DOE PAGES

    Sirunyan, A. M.; Tumasyan, A.; Adam, W.; ...

    2017-04-21

    Here, the CMS tracker consists of 206 m 2 of silicon strip sensors assembled on carbon fibre composite structures and is designed for operation in the temperature range from –25 to +25°C. The mechanical stability of tracker components during physics operation was monitored with a few μm resolution using a dedicated laser alignment system as well as particle tracks from cosmic rays and hadron-hadron collisions. During the LHC operational period of 2011–2013 at stable temperatures, the components of the tracker were observed to experience relative movements of less than 30μm. In addition, temperature variations were found to cause displacements ofmore » tracker structures of about 2μm°C, which largely revert to their initial positions when the temperature is restored to its original value.« less

  8. Assessment of the U. S. outer continental shelf environmental studies program. 1. Physical oceanography. Final report

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

    Not Available

    Federal responsibility for oil and gas development on the U.S. outer continental shelf (OCS) resides with the Minerals Management Service (MMS) of the U.S. Department of the Interior (DOI). The DOI's Environmental Studies Program (ESP) is the program through which MMS conducts environmental studies on the OCS and collects information to prepare environmental impact statements (EISs). It appeared to MMS in 1986 that the time was ripe to assess the status of the present program and to explore the needs for future studies. MMS requested an evaluation of the adequacy and applicability of ESP studies, a review of the generalmore » state of knowledge in the appropriate disciplines, and recommendations for future studies. Three panels were established, one of which, the Physical Oceanography Panel, investigated the physical oceanographic aspects of the ESP, the subject of the report, which is the first of three in a series. In reviewing the ESP's physical oceanography program, the panel evaluated the quality and relevance of studies carried out in waters under federal control, which extend from the limits of state jurisdictions (3-12 miles offshore) and include the central and outer continental shelf waters and the continental slope.« less

  9. Toward Understanding the Outer Membrane Uptake of Small Molecules by Pseudomonas aeruginosa*

    PubMed Central

    Eren, Elif; Parkin, Jamie; Adelanwa, Ayodele; Cheneke, Belete; Movileanu, Liviu; Khalid, Syma; van den Berg, Bert

    2013-01-01

    Because small molecules enter Gram-negative bacteria via outer membrane (OM) channels, understanding OM transport is essential for the rational design of improved and new antibiotics. In the human pathogen Pseudomonas aeruginosa, most small molecules are taken up by outer membrane carboxylate channel (Occ) proteins, which can be divided into two distinct subfamilies, OccD and OccK. Here we characterize substrate transport mediated by Occ proteins belonging to both subfamilies. Based on the determination of the OccK2-glucuronate co-crystal structure, we identify the channel residues that are essential for substrate transport. We further show that the pore regions of the channels are rigid in the OccK subfamily and highly dynamic in the OccD subfamily. We also demonstrate that the substrate carboxylate group interacts with central residues of the basic ladder, a row of arginine and lysine residues that leads to and away from the binding site at the channel constriction. Moreover, the importance of the basic ladder residues corresponds to their degree of conservation. Finally, we apply the generated insights by converting the archetype of the entire family, OccD1, from a basic amino acid-specific channel into a channel with a preference for negatively charged amino acids. PMID:23467408

  10. WARFIGHTER SUPPORT: Independent Expert Assessment of Army Body Armor Test Results and Procedures Needed Before Fielding

    DTIC Science & Technology

    2009-10-01

    protective vest and ceramic plate inserts. GAO observed Preliminary Design Model testing of new plate designs, which resulted in the Army’s...Table 1: Organizations Contacted for Information about Body Armor Testing 46 Figures Figure 1: ESAPI Plates as Worn inside Outer Tactical Vest 11...Central Command has required that DOD personnel in its area of operations be issued the Interceptor Body Armor system, comprising ceramic plates that

  11. Notes on Barkas-Andersen effect

    NASA Astrophysics Data System (ADS)

    Sigmund, Peter; Schinner, Andreas

    2014-10-01

    Stimulated by recent statements in the literature on electronic stopping of heavy ions in matter, we try to clarify some central theoretical aspects of the Barkas-Andersen effect, about which there does not seem to be unanimous agreement in the community. We address the role of inner versus outer target shells, of projectile screening by bound electrons, the interference between Lindhard's description and perturbation theory, as well as the equivalence between a single-electron versus Fermi-gas description of the effect.

  12. Banded electromagnetic stator core

    DOEpatents

    Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

    1996-06-11

    A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figs.

  13. Banded electromagnetic stator core

    DOEpatents

    Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

    1994-04-05

    A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figures.

  14. Simulations of Ar gas-puff Z-pinch radiation sources with double shells and central jets on the Z generator

    DOE PAGES

    Tangri, V.; Harvey-Thompson, Adam James; Giuliani, J. L.; ...

    2016-10-19

    Radiation-magnetohydrodynamic simulations using the non-LTE Mach2-TCRE code in (r,z) geometry are performed for two pairs of recent Ar gas-puff Z-pinch experiments on the refurbished Z generator with an 8 cm diameter nozzle. One pair of shots had an outer-to-inner shell mass ratio of 1:1.6 and a second pair had a ratio of 1:1.

  15. Structure of a prokaryotic sodium channel pore reveals essential gating elements and an outer ion binding site common to eukaryotic channels.

    PubMed

    Shaya, David; Findeisen, Felix; Abderemane-Ali, Fayal; Arrigoni, Cristina; Wong, Stephanie; Nurva, Shailika Reddy; Loussouarn, Gildas; Minor, Daniel L

    2014-01-23

    Voltage-gated sodium channels (NaVs) are central elements of cellular excitation. Notwithstanding advances from recent bacterial NaV (BacNaV) structures, key questions about gating and ion selectivity remain. Here, we present a closed conformation of NaVAe1p, a pore-only BacNaV derived from NaVAe1, a BacNaV from the arsenite oxidizer Alkalilimnicola ehrlichei found in Mono Lake, California, that provides insight into both fundamental properties. The structure reveals a pore domain in which the pore-lining S6 helix connects to a helical cytoplasmic tail. Electrophysiological studies of full-length BacNaVs show that two elements defined by the NaVAe1p structure, an S6 activation gate position and the cytoplasmic tail "neck", are central to BacNaV gating. The structure also reveals the selectivity filter ion entry site, termed the "outer ion" site. Comparison with mammalian voltage-gated calcium channel (CaV) selectivity filters, together with functional studies, shows that this site forms a previously unknown determinant of CaV high-affinity calcium binding. Our findings underscore commonalities between BacNaVs and eukaryotic voltage-gated channels and provide a framework for understanding gating and ion permeation in this superfamily. © 2013. Published by Elsevier Ltd. All rights reserved.

  16. Associations between alcohol outlets and emergency department injury presentations: effects of distance from the central business district.

    PubMed

    Hobday, Michelle; Meuleners, Lynn; Liang, Wenbin; Gilmore, William; Chikritzhs, Tanya

    2016-02-01

    To examine the effects of licensed outlets and sales on levels of alcohol-related injuries presenting to emergency departments (EDs) in the Inner, Middle and Outer postcode zones of Perth, Australia. Using panel data (2002-2010), a surrogate measure (based on day of week and time of day of presentation) was used to identify alcohol-related injuries presenting at EDs. Postcodes were grouped according to their distance from the central business district (CBD). Numbers of alcohol outlets and their sales were the primary explanatory variables. Data were analysed using negative binomial regression with random effects. In the Inner and Outer postcode zones, counts of on-site outlets were positively associated with alcohol-related injury (IRR: 1.008; 95%CI 1.003-1.013 and IRR: 1.021; 95%CI 1.013-1.030 respectively). An additional off-site outlet was associated with 6.8% fewer alcohol-related injuries (95%CI 0.887-0.980). In the Middle postcode zone, mean off-site sales were positively associated with injury (IRR: 1.024; 95%CI 1.003-1.044). Associations between alcohol availability variables and injury differed by outlet type and distance from the CBD. These findings provide further evidence to support stronger controls on liquor licensing, and indicate the need for different controls according to the location and type of licence. © 2015 Public Health Association of Australia.

  17. Two-fluid flowing equilibria of spherical torus sustained by coaxial helicity injection

    NASA Astrophysics Data System (ADS)

    Kanki, Takashi; Steinhauer, Loren; Nagata, Masayoshi

    2007-11-01

    Two-dimensional equilibria in helicity-driven systems using two-fluid model were previously computed, showing the existence of an ultra-low-q spherical torus (ST) configuration with diamagnetism and higher beta. However, this computation assumed purely toroidal ion flow and uniform density. The purpose of the present study is to apply the two-fluid model to the two-dimensional equilibria of helicity-driven ST with non-uniform density and both toroidal and poloidal flows for each species by means of the nearby-fluids procedure, and to explore their properties. We focus our attention on the equilibria relevant to the HIST device, which are characterized by either driven or decaying λ profiles. The equilibrium for the driven λ profile has a diamagnetic toroidal field, high-β (βt = 32%), and centrally broad density. By contrast, the decaying equilibrium has a paramagnetic toroidal field, low-β (βt = 10%), and centrally peaked density with a steep gradient in the outer edge region. In the driven case, the toroidal ion and electron flows are in the same direction, and two-fluid effects are less important since the ExB drift is dominant. In the decaying case, the toroidal ion and electron flows are opposite in the outer edge region, and two-fluid effects are significant locally in the edge due to the ion diamagnetic drift.

  18. Chandra X-Ray Observatory Image of Eta Carinae

    NASA Technical Reports Server (NTRS)

    1999-01-01

    This Chandra X-Ray Observatory image of the mysterious superstar Eta Carinae reveals a surprising hot irner core, creating more questions than answers for astronomers. The image shows three distinct structures: An outer, horseshoe shaped ring about 2 light-years in diameter, a hot inner core about 3 light-months in diameter, and a hot central source less than a light-month in diameter which may contain the superstar. In 1 month, light travels a distance of approximately 489 billion miles (about 788 billion kilometers). All three structures are thought to represent shock waves produced by matter rushing away from the superstar at supersonic speeds. The temperature of the shock-heated gas ranges from 60 million degrees Kelvin in the central regions to 7 million degrees Kelvin on the outer structure. Eta Carinae is one of the most enigmatic and intriguing objects in our galaxy. Between 1837 and 1856, it increased dramatically in brightness to become the most prominent star in the sky except for Sirius, even through it is 7,500 light-years away, more than 80 times the distance to Sirius. This 'Great Eruption,' as it is called, had an energy comparable to a supernova, yet did not destroy the star, which faded to become a dim star, invisible to the naked eye. Since 1940, Eta Carinae has begun to brighten again, becoming visible to the naked eye. Photo credit: NASA/CXC/SAO

  19. An L-band transit-time oscillator with mechanical frequency tunability

    NASA Astrophysics Data System (ADS)

    Song, Lili; He, Juntao; Ling, Junpu; Cao, Yibing

    2017-02-01

    An L-band coaxial Transit-time Oscillator (TTO) with mechanical frequency tunability is introduced in this paper. Particle-in-cell simulations have been done. The output power efficiency has been improved at least 20% under a 10.2 GW input power and with a tunable range from 1.57 GHz to 1.90 GHz by modulating the outer conductor. It is worth to note that the efficiency can reach as high as 41% at 1.75 GHz. The mechanical engineering method is also detailed in this work. The frequency tuning range of the coaxial TTO is 22.6% of the central frequency. On the other hand, the frequency can be tuned from 1.6 GHz to 1.85 GHz by modulating the inner conductor. The author highlights a hollow structure of the L-band coaxial TTO which can work from 1.03 GHz to 1.31 GHz via modulating the outer conductor in the rest of the article. The frequency tuning range of the hollow TTO is 21.4% of the central frequency. More importantly, the hollow TTO can be easily achieved after the inner conductor is removed from the coaxial TTO. The electric field distributions of the coaxial and hollow TTOs are analyzed, resulting in that the longitudinal and transverse working modes are TM01 and π mode, respectively. The same working mode from these two structures implies the stability of the TTOs mentioned above.

  20. A Statistical Study of Rapid Sunspot Structure Change Associated with Flares

    NASA Astrophysics Data System (ADS)

    Chen, Wei-Zhong; Liu, Chang; Song, Hui; Deng, Na; Tan, Chang-Yi; Wang, Hai-Min

    2007-10-01

    We reported recently some rapid changes of sunspot structure in white-light (WL) associated with major flares. We extend the study to smaller events and present here results of a statistical study of this phenomenon. In total, we investigate 403 events from 1998 May 9 to 2004 July 17, including 40 X-class, 174 M-class, and 189 C-class flares. By monitoring the structure of the flaring active regions using the WL observations from the Transition Region and Coronal Explorer (TRACE), we find that segments in the outer sunspot structure decayed rapidly right after many flares; and that, on the other hand, the central part of sunspots near the flare-associated magnetic neutral line became darkened. These rapid and permanent changes are evidenced in the time profiles of WL mean intensity and are not likely resulted from the flare emissions. Our study further shows that the outer sunspot structure decay as well as the central structure darkening are more likely to be detected in larger solar flares. For X-class flares, over 40% events show distinct sunspot structure change. For M- and C-class flares, this percentage drops to 17% and 10%, respectively. The results of this statistical study support our previously proposed reconnection picture, i.e., the flare-related magnetic fields evolve from a highly inclined to a more vertical configuration.

  1. Reduction of foveal bulges and other anatomical changes in fellow eyes of patients with unilateral idiopathic macular hole without vitreomacular pathologic changes.

    PubMed

    Delas, Barbara; Julio, Gemma; Fernández-Vega, Álvaro; Casaroli-Marano, Ricardo P; Nadal, Jeroni

    2017-11-01

    To compare the foveal characteristics in fellow eyes (FE) of patients with unilateral idiopathic macular hole without vitreomacular pathologic changes with eyes of healthy controls. Forty-seven FE and 52 eyes of 52 age- and sex-matched healthy controls were studied. Quantitative assessment of the dome-shaped appearance of the hyperreflective lines that represent external limiting membrane (ELM_bulge) and inner outer segment junctions (IS/OS_bulge) were made by optical coherence tomography (OCT) images. Inner retinal complex thickness (IRCT) was quantitatively assessed at 1000 and 2000 μm of the foveal center in nasal and temporal quadrants. Presence of alterations in the inner retinal outer layers and central foveal thickness (CFT) were also analyzed. Significantly lower ELM_bulge (p < 0.0001; Mann-Whitney test) and IS/OS_bulge (p < 0.001; student t test) and higher cases with COST alterations, expressed as a diffuse line (p < 0.006; Chi 2 test) were found in FE than control eyes. IRCT were significantly reduced in FE at all the studied locations when comparing to control eyes (p < 0.05; student t test), maintaining anatomical proportionality among locations. FE without pathologic vitreomacular interactions seems to present some central cone alterations that may be related to other causes than vitreomacular traction.

  2. Behavioral responses of one western lowland gorilla (Gorilla gorilla gorilla) group at Bai Hokou, Central African Republic, to tourists, researchers and trackers.

    PubMed

    Klailova, Michelle; Hodgkinson, Chloe; Lee, Phyllis C

    2010-09-01

    Gorilla tourism, widely perceived as a lucrative industry, is propelled by strong market demand with programs in five countries and for three of four gorilla subspecies. Human presence may negatively affect wild gorillas, potentially lowering immunity and increasing the likelihood of acquiring human-borne disease. Yet, behavioral impacts of humans on wild gorilla behavior remain largely unexplored, particularly for western lowland gorillas. We evaluate the impact of tourist presence, human observer numbers (tourists, trackers, and researchers), and human observer distance on the behavior of one habituated gorilla group at Bai Hokou, Central African Republic. Behavioral data were collected for more than 12 months from January 2007. Of silverback aggressive events, 39% (N=229) were human directed, but 65% were low-level soft barks. Adult females, and one in particular, were responsible for the highest number of aggressive events toward humans. Humans maintained closer proximity to the silverback when tourists were present, although tourist numbers had no significant impact on overall group activity budgets or rates of human-directed aggression. However, as research team size increased, group feeding rates decreased. Close observer-silverback distance correlated with a decrease in his feeding rates and an increase in human monitoring. He directed less aggression toward observers at distances >10 m, although observers spent 48.5% of time between 6 and 10 m of the silverback. We discuss gorilla personality as a factor in human-directed aggression. We explore whether the current 7 m distance limit governing gorilla tourism, based on disease transmission risks, is sufficient considering the potential behavioral stressor of close human presence. We recommend increasing minimum observation distance to >10 m where possible, decreasing observer group sizes, particularly after a visit consisting of maximum numbers and restricting tourist access to 1 visit/day. 2010 Wiley-Liss, Inc.

  3. Adaptive Neural Star Tracker Calibration for Precision Spacecraft Pointing and Tracking

    NASA Technical Reports Server (NTRS)

    Bayard, David S.

    1996-01-01

    The Star Tracker is an essential sensor for precision pointing and tracking in most 3-axis stabilized spacecraft. In the interest (of) improving pointing performance by taking advantage of dramatic increases in flight computer power and memory anticipated over the next decade, this paper investigates the use of a neural net for adaptive in-flight calibration of the Star Tracker.

  4. Improvement of Hungarian Joint Terminal Attack Program

    DTIC Science & Technology

    2013-06-13

    LST Laser Spot Tracker NVG Night Vision Goggle ROMAD Radio Operator Maintainer and Driver ROVER Remotely Operated Video Enhanced Receiver TACP...visual target designation. The other component consists of a laser spot tracker (LST), which identifies targets by tracking laser energy reflecting...capability for every type of night time missions, laser spot tracker for laser spot search missions, remotely operated video enhanced receiver

  5. A survey of current solid state star tracker technology

    NASA Astrophysics Data System (ADS)

    Armstrong, R. W.; Staley, D. A.

    1985-12-01

    This paper is a survey of the current state of the art in design of star trackers for spacecraft attitude determination systems. Specific areas discussed are sensor technology, including the current state-of-the-art solid state sensors and techniques of mounting and cooling the sensor, analog image preprocessing electronics performance, and digital processing hardware and software. Three examples of area array solid state star tracker development are presented - ASTROS, developed by the Jet Propulsion Laboratory, the Retroreflector Field Tracker (RFT) by Ball Aerospace, and TRW's MADAN. Finally, a discussion of solid state line arrays explores the possibilities for one-dimensional imagers which offer simplified scan control electronics.

  6. An accuracy measurement method for star trackers based on direct astronomic observation

    PubMed Central

    Sun, Ting; Xing, Fei; Wang, Xiaochu; You, Zheng; Chu, Daping

    2016-01-01

    Star tracker is one of the most promising optical attitude measurement devices and it is widely used in spacecraft for its high accuracy. However, how to realize and verify such an accuracy remains a crucial but unsolved issue until now. The authenticity of the accuracy measurement method of a star tracker will eventually determine the satellite performance. A new and robust accuracy measurement method for a star tracker based on the direct astronomical observation is proposed here. In comparison with the conventional method with simulated stars, this method utilizes real navigation stars as observation targets which makes the measurement results more authoritative and authentic. Transformations between different coordinate systems are conducted on the account of the precision movements of the Earth, and the error curves of directional vectors are obtained along the three axes. Based on error analysis and accuracy definitions, a three-axis accuracy evaluation criterion has been proposed in this paper, which could determine pointing and rolling accuracy of a star tracker directly. Experimental measurements confirm that this method is effective and convenient to implement. Such a measurement environment is close to the in-orbit conditions and it can satisfy the stringent requirement for high-accuracy star trackers. PMID:26948412

  7. Exposure Time Optimization for Highly Dynamic Star Trackers

    PubMed Central

    Wei, Xinguo; Tan, Wei; Li, Jian; Zhang, Guangjun

    2014-01-01

    Under highly dynamic conditions, the star-spots on the image sensor of a star tracker move across many pixels during the exposure time, which will reduce star detection sensitivity and increase star location errors. However, this kind of effect can be compensated well by setting an appropriate exposure time. This paper focuses on how exposure time affects the star tracker under highly dynamic conditions and how to determine the most appropriate exposure time for this case. Firstly, the effect of exposure time on star detection sensitivity is analyzed by establishing the dynamic star-spot imaging model. Then the star location error is deduced based on the error analysis of the sub-pixel centroiding algorithm. Combining these analyses, the effect of exposure time on attitude accuracy is finally determined. Some simulations are carried out to validate these effects, and the results show that there are different optimal exposure times for different angular velocities of a star tracker with a given configuration. In addition, the results of night sky experiments using a real star tracker agree with the simulation results. The summarized regularities in this paper should prove helpful in the system design and dynamic performance evaluation of the highly dynamic star trackers. PMID:24618776

  8. An accuracy measurement method for star trackers based on direct astronomic observation.

    PubMed

    Sun, Ting; Xing, Fei; Wang, Xiaochu; You, Zheng; Chu, Daping

    2016-03-07

    Star tracker is one of the most promising optical attitude measurement devices and it is widely used in spacecraft for its high accuracy. However, how to realize and verify such an accuracy remains a crucial but unsolved issue until now. The authenticity of the accuracy measurement method of a star tracker will eventually determine the satellite performance. A new and robust accuracy measurement method for a star tracker based on the direct astronomical observation is proposed here. In comparison with the conventional method with simulated stars, this method utilizes real navigation stars as observation targets which makes the measurement results more authoritative and authentic. Transformations between different coordinate systems are conducted on the account of the precision movements of the Earth, and the error curves of directional vectors are obtained along the three axes. Based on error analysis and accuracy definitions, a three-axis accuracy evaluation criterion has been proposed in this paper, which could determine pointing and rolling accuracy of a star tracker directly. Experimental measurements confirm that this method is effective and convenient to implement. Such a measurement environment is close to the in-orbit conditions and it can satisfy the stringent requirement for high-accuracy star trackers.

  9. Analyzing Virtual Physics Simulations with Tracker

    NASA Astrophysics Data System (ADS)

    Claessens, Tom

    2017-12-01

    In the physics teaching community, Tracker is well known as a user-friendly open source video analysis software, authored by Douglas Brown. With this tool, the user can trace markers indicated on a video or on stroboscopic photos and perform kinematic analyses. Tracker also includes a data modeling tool that allows one to fit some theoretical equations of motion onto experimentally obtained data. In the field of particle mechanics, Tracker has been effectively used for learning and teaching about projectile motion, "toss up" and free-fall vertical motion, and to explain the principle of mechanical energy conservation. Also, Tracker has been successfully used in rigid body mechanics to interpret the results of experiments with rolling/slipping cylinders and moving rods. In this work, I propose an original method in which Tracker is used to analyze virtual computer simulations created with a physics-based motion solver, instead of analyzing video recording or stroboscopic photos. This could be an interesting approach to study kinematics and dynamics problems in physics education, in particular when there is no or limited access to physical labs. I demonstrate the working method with a typical (but quite challenging) problem in classical mechanics: a slipping/rolling cylinder on a rough surface.

  10. TE-Tracker: systematic identification of transposition events through whole-genome resequencing.

    PubMed

    Gilly, Arthur; Etcheverry, Mathilde; Madoui, Mohammed-Amin; Guy, Julie; Quadrana, Leandro; Alberti, Adriana; Martin, Antoine; Heitkam, Tony; Engelen, Stefan; Labadie, Karine; Le Pen, Jeremie; Wincker, Patrick; Colot, Vincent; Aury, Jean-Marc

    2014-11-19

    Transposable elements (TEs) are DNA sequences that are able to move from their location in the genome by cutting or copying themselves to another locus. As such, they are increasingly recognized as impacting all aspects of genome function. With the dramatic reduction in cost of DNA sequencing, it is now possible to resequence whole genomes in order to systematically characterize novel TE mobilization in a particular individual. However, this task is made difficult by the inherently repetitive nature of TE sequences, which in some eukaryotes compose over half of the genome sequence. Currently, only a few software tools dedicated to the detection of TE mobilization using next-generation-sequencing are described in the literature. They often target specific TEs for which annotation is available, and are only able to identify families of closely related TEs, rather than individual elements. We present TE-Tracker, a general and accurate computational method for the de-novo detection of germ line TE mobilization from re-sequenced genomes, as well as the identification of both their source and destination sequences. We compare our method with the two classes of existing software: specialized TE-detection tools and generic structural variant (SV) detection tools. We show that TE-Tracker, while working independently of any prior annotation, bridges the gap between these two approaches in terms of detection power. Indeed, its positive predictive value (PPV) is comparable to that of dedicated TE software while its sensitivity is typical of a generic SV detection tool. TE-Tracker demonstrates the benefit of adopting an annotation-independent, de novo approach for the detection of TE mobilization events. We use TE-Tracker to provide a comprehensive view of transposition events induced by loss of DNA methylation in Arabidopsis. TE-Tracker is freely available at http://www.genoscope.cns.fr/TE-Tracker . We show that TE-Tracker accurately detects both the source and destination of novel transposition events in re-sequenced genomes. Moreover, TE-Tracker is able to detect all potential donor sequences for a given insertion, and can identify the correct one among them. Furthermore, TE-Tracker produces significantly fewer false positives than common SV detection programs, thus greatly facilitating the detection and analysis of TE mobilization events.

  11. The Heterogeneity and Spatial Patterning of Structure and Physiology across the Leaf Surface in Giant Leaves of Alocasia macrorrhiza

    PubMed Central

    Li, Shuai; Zhang, Yong-Jiang; Sack, Lawren; Scoffoni, Christine; Ishida, Atsushi; Chen, Ya-Jun; Cao, Kun-Fang

    2013-01-01

    Leaf physiology determines the carbon acquisition of the whole plant, but there can be considerable variation in physiology and carbon acquisition within individual leaves. Alocasia macrorrhiza (L.) Schott is an herbaceous species that can develop very large leaves of up to 1 m in length. However, little is known about the hydraulic and photosynthetic design of such giant leaves. Based on previous studies of smaller leaves, and on the greater surface area for trait variation in large leaves, we hypothesized that A. macrorrhiza leaves would exhibit significant heterogeneity in structure and function. We found evidence of reduced hydraulic supply and demand in the outer leaf regions; leaf mass per area, chlorophyll concentration, and guard cell length decreased, as did stomatal conductance, net photosynthetic rate and quantum efficiency of photosystem II. This heterogeneity in physiology was opposite to that expected from a thinner boundary layer at the leaf edge, which would have led to greater rates of gas exchange. Leaf temperature was 8.8°C higher in the outer than in the central region in the afternoon, consistent with reduced stomatal conductance and transpiration caused by a hydraulic limitation to the outer lamina. The reduced stomatal conductance in the outer regions would explain the observed homogeneous distribution of leaf water potential across the leaf surface. These findings indicate substantial heterogeneity in gas exchange across the leaf surface in large leaves, greater than that reported for smaller-leafed species, though the observed structural differences across the lamina were within the range reported for smaller-leafed species. Future work will determine whether the challenge of transporting water to the outer regions can limit leaf size for plants experiencing drought, and whether the heterogeneity of function across the leaf surface represents a particular disadvantage for large simple leaves that might explain their global rarity, even in resource-rich environments. PMID:23776594

  12. The heterogeneity and spatial patterning of structure and physiology across the leaf surface in giant leaves of Alocasia macrorrhiza.

    PubMed

    Li, Shuai; Zhang, Yong-Jiang; Sack, Lawren; Scoffoni, Christine; Ishida, Atsushi; Chen, Ya-Jun; Cao, Kun-Fang

    2013-01-01

    Leaf physiology determines the carbon acquisition of the whole plant, but there can be considerable variation in physiology and carbon acquisition within individual leaves. Alocasia macrorrhiza (L.) Schott is an herbaceous species that can develop very large leaves of up to 1 m in length. However, little is known about the hydraulic and photosynthetic design of such giant leaves. Based on previous studies of smaller leaves, and on the greater surface area for trait variation in large leaves, we hypothesized that A. macrorrhiza leaves would exhibit significant heterogeneity in structure and function. We found evidence of reduced hydraulic supply and demand in the outer leaf regions; leaf mass per area, chlorophyll concentration, and guard cell length decreased, as did stomatal conductance, net photosynthetic rate and quantum efficiency of photosystem II. This heterogeneity in physiology was opposite to that expected from a thinner boundary layer at the leaf edge, which would have led to greater rates of gas exchange. Leaf temperature was 8.8°C higher in the outer than in the central region in the afternoon, consistent with reduced stomatal conductance and transpiration caused by a hydraulic limitation to the outer lamina. The reduced stomatal conductance in the outer regions would explain the observed homogeneous distribution of leaf water potential across the leaf surface. These findings indicate substantial heterogeneity in gas exchange across the leaf surface in large leaves, greater than that reported for smaller-leafed species, though the observed structural differences across the lamina were within the range reported for smaller-leafed species. Future work will determine whether the challenge of transporting water to the outer regions can limit leaf size for plants experiencing drought, and whether the heterogeneity of function across the leaf surface represents a particular disadvantage for large simple leaves that might explain their global rarity, even in resource-rich environments.

  13. SPH Simulations of Spherical Bondi Accretion: First Step of Implementing AGN Feedback in Galaxy Formation

    NASA Astrophysics Data System (ADS)

    Barai, Paramita; Proga, D.; Nagamine, K.

    2011-01-01

    Our motivation is to numerically test the assumption of Black Hole (BH) accretion (that the central massive BH of a galaxy accretes mass at the Bondi-Hoyle accretion rate, with ad-hoc choice of parameters), made in many previous galaxy formation studies including AGN feedback. We perform simulations of a spherical distribution of gas, within the radius range 0.1 - 200 pc, accreting onto a central supermassive black hole (the Bondi problem), using the 3D Smoothed Particle Hydrodynamics code Gadget. In our simulations we study the radial distribution of various gas properties (density, velocity, temperature, Mach number). We compute the central mass inflow rate at the inner boundary (0.1 pc), and investigate how different gas properties (initial density and velocity profiles) and computational parameters (simulation outer boundary, particle number) affect the central inflow. Radiative processes (namely heating by a central X-ray corona and gas cooling) have been included in our simulations. We study the thermal history of accreting gas, and identify the contribution of radiative and adiabatic terms in shaping the gas properties. We find that the current implementation of artificial viscosity in the Gadget code causes unwanted extra heating near the inner radius.

  14. A star tracker insensitive to stray light generated by radiation sources close to the field of view

    NASA Astrophysics Data System (ADS)

    Romoli, A.; Gambicorti, L.; Simonetti, F.; Zuccaro Marchi, A.

    2017-11-01

    Aim of this work is to propose an innovative star tracker, practically insensitive to the radiation coming from the sun or from other strong planetary sources out of (but near) the Field of View. These sources need to be stopped in some way. The classical solution to reject the unwanted radiation is to place a shadow (or baffle) before the star tracker objective. The shadow size depends on the Field of View and on the minimum angle subtended by the source (i.e. the sun) with respect to the optical axis of the star tracker. The lower is this angle the larger is the shadow. Requests for star trackers able to work with the sun as close as possible to the Field of View are increasing, due to the need of maximum mission flexibility. The innovation of this proposed star tracker is conceived by using spatial filtering with a concept complementary to that of coronagraph for sun corona observation, allowing to drastically reduce the size of the shadow. It can also work close to antennas and other part of the platform, which, when illuminated by the sun, become secondary sources capable to blind the star tracker. This kind of accommodation offers three main advantages: no cumbersome shadows (baffle), maximum flexibility in terms of mission profile, less platform location constraints. This new star sensor concept, dated 2007, is now patent pending. Galileo Avionica (now Selex Galileo) is the owner of the patent.

  15. Tracker-on-C for cone-beam CT-guided surgery: evaluation of geometric accuracy and clinical applications

    NASA Astrophysics Data System (ADS)

    Reaungamornrat, S.; Otake, Y.; Uneri, A.; Schafer, S.; Mirota, D. J.; Nithiananthan, S.; Stayman, J. W.; Khanna, A. J.; Reh, D. D.; Gallia, G. L.; Taylor, R. H.; Siewerdsen, J. H.

    2012-02-01

    Conventional surgical tracking configurations carry a variety of limitations in line-of-sight, geometric accuracy, and mismatch with the surgeon's perspective (for video augmentation). With increasing utilization of mobile C-arms, particularly those allowing cone-beam CT (CBCT), there is opportunity to better integrate surgical trackers at bedside to address such limitations. This paper describes a tracker configuration in which the tracker is mounted directly on the Carm. To maintain registration within a dynamic coordinate system, a reference marker visible across the full C-arm rotation is implemented, and the "Tracker-on-C" configuration is shown to provide improved target registration error (TRE) over a conventional in-room setup - (0.9+/-0.4) mm vs (1.9+/-0.7) mm, respectively. The system also can generate digitally reconstructed radiographs (DRRs) from the perspective of a tracked tool ("x-ray flashlight"), the tracker, or the C-arm ("virtual fluoroscopy"), with geometric accuracy in virtual fluoroscopy of (0.4+/-0.2) mm. Using a video-based tracker, planning data and DRRs can be superimposed on the video scene from a natural perspective over the surgical field, with geometric accuracy (0.8+/-0.3) pixels for planning data overlay and (0.6+/-0.4) pixels for DRR overlay across all C-arm angles. The field-of-view of fluoroscopy or CBCT can also be overlaid on real-time video ("Virtual Field Light") to assist C-arm positioning. The fixed transformation between the x-ray image and tracker facilitated quick, accurate intraoperative registration. The workflow and precision associated with a variety of realistic surgical tasks were significantly improved using the Tracker-on-C - for example, nearly a factor of 2 reduction in time required for C-arm positioning, reduction or elimination of dose in "hunting" for a specific fluoroscopic view, and confident placement of the x-ray FOV on the surgical target. The proposed configuration streamlines the integration of C-arm CBCT with realtime tracking and demonstrated utility in a spectrum of image-guided interventions (e.g., spine surgery) benefiting from improved accuracy, enhanced visualization, and reduced radiation exposure.

  16. A Bit of Fit: Minimalist Intervention in Adolescents Based on a Physical Activity Tracker

    PubMed Central

    Gaudet, Jeffrey; Gallant, François

    2017-01-01

    Background Only 5% of Canadian youth meet the recommended 60 minutes of moderate to vigorous physical activity (MVPA) per day, with leisure time being increasingly allocated to technology usage. Direct-to-consumer mHealth devices that promote physical activity, such as wrist-worn physical activity trackers, have features with potential appeal to youth. Objective The primary purpose of this study was to determine whether a minimalist physical activity tracker-based intervention would lead to an increase in physical activity in young adolescents. A secondary aim of this study was to assess change in physical activity across a 7-week intervention, as measured by the tracker. Methods Using a quasi-experimental crossover design, two groups of 23 young adolescents (aged 13-14 years) were randomly assigned to immediate intervention or delayed intervention. The intervention consisted of wearing a Fitbit-Charge-HR physical activity tracker over a 7-week period. Actical accelerometers were used to measure participants’ levels of MVPA before and at the end of intervention periods for each group. Covariates such as age, sex, stage of change for physical activity behavior, and goal commitment were also measured. Results There was an increase in physical activity over the course of the study period, though it was not related to overall physical activity tracker use. An intervention response did, however, occur in a subset of participants. Specifically, exposure to the physical activity tracker was associated with an average daily increase in MVPA by more than 15 minutes (P=.01) among participants who reported being in the action and maintenance stages of behavior change in relation to participation in physical activity. Participants in the precontemplation, contemplation, and preparation stages of behavior change had no change in their level of MVPA (P=.81). Conclusions These results suggest that physical activity trackers may elicit improved physical activity related behavior in young adolescents demonstrating a readiness to be active. Future studies should seek to investigate if integrating physical activity trackers as part of more intensive interventions leads to greater increases in physical activity across different levels of stages of behavior change and if these changes can be sustained over longer periods of time. PMID:28684384

  17. Photoluminescent silicon nanocrystal-based multifunctional carrier for pH-regulated drug delivery.

    PubMed

    Xu, Zhigang; Wang, Dongdong; Guan, Min; Liu, Xiaoyan; Yang, Yanjie; Wei, Dongfeng; Zhao, Chunyan; Zhang, Haixia

    2012-07-25

    A core-shell structured multifunctional carrier with nanocrystalline silicon (ncSi) as the core and a water-soluble block copolymer as the shell based on a poly(methacrylic acid) (PMAA) inner shell and polyethylene glycol (MPEG) outer shell (ncSi-MPM) was synthesized for drug delivery. The morphology, composition, and properties of the resulting ncSi-MPM were determined by comprehensive multianalytical characterization, including (1)H NMR spectroscopy, FTIR spectroscopy, XPS spectroscopy, TEM, DLS, and fluorescence spectroscopy analyses. The size of the resulting ncSi-MPM nanocarriers ranged from 40 to 110 nm under a simulated physiological environment. The loading efficiency of model drug doxorubicin (DOX) was approximately 6.1-7.4 wt % for ncSi-MPM and the drug release was pH controlled. Cytotoxicity studies demonstrated that DOX-loaded ncSi-MPM showed high anticancer activity against Hela cells. Hemolysis percentages (<2%) of ncSi-MPM were within the scope of safe values. Fluorescent imaging studies showed that the nanocarriers could be used as a tracker at the cellular level. Integration of the above functional components may result in ncSi-MPM becoming a promising multifunctional carrier for drug delivery and biomedical applications.

  18. On-Orbit Solar Dynamics Observatory (SDO) Star Tracker Warm Pixel Analysis

    NASA Technical Reports Server (NTRS)

    Felikson, Denis; Ekinci, Matthew; Hashmall, Joseph A.; Vess, Melissa

    2011-01-01

    This paper describes the process of identification and analysis of warm pixels in two autonomous star trackers on the Solar Dynamics Observatory (SDO) mission. A brief description of the mission orbit and attitude regimes is discussed and pertinent star tracker hardware specifications are given. Warm pixels are defined and the Quality Index parameter is introduced, which can be explained qualitatively as a manifestation of a possible warm pixel event. A description of the algorithm used to identify warm pixel candidates is given. Finally, analysis of dumps of on-orbit star tracker charge coupled devices (CCD) images is presented and an operational plan going forward is discussed. SDO, launched on February 11, 2010, is operated from the NASA Goddard Space Flight Center (GSFC). SDO is in a geosynchronous orbit with a 28.5 inclination. The nominal mission attitude points the spacecraft X-axis at the Sun, with the spacecraft Z-axis roughly aligned with the Solar North Pole. The spacecraft Y-axis completes the triad. In attitude, SDO moves approximately 0.04 per hour, mostly about the spacecraft Z-axis. The SDO star trackers, manufactured by Galileo Avionica, project the images of stars in their 16.4deg x 16.4deg fields-of-view onto CCD detectors consisting of 512 x 512 pixels. The trackers autonomously identify the star patterns and provide an attitude estimate. Each unit is able to track up to 9 stars. Additionally, each tracker calculates a parameter called the Quality Index, which is a measure of the quality of the attitude solution. Each pixel in the CCD measures the intensity of light and a warns pixel is defined as having a measurement consistently and significantly higher than the mean background intensity level. A warns pixel should also have lower intensity than a pixel containing a star image and will not move across the field of view as the attitude changes (as would a dim star image). It should be noted that the maximum error introduced in the star tracker attitude solution during suspected warm pixel corruptions is within the specified 36 attitude error budget requirement of [35, 70, 70] arcseconds. Thus, the star trackers provided attitude accuracy within the specification for SDO. The star tracker images are intentionally defocused so each star image is detected in more than one CCD pixel. The position of each star is calculated as an intensity-weighted average of the illuminated pixels. The exact method of finding the positions is proprietary to the tracker manufacturer. When a warm pixel happens to be in the vicinity of a star, it can corrupt the calculation of the position of that particular star, thereby corrupting the estimate of the attitude.

  19. User Acceptance of Wrist-Worn Activity Trackers Among Community-Dwelling Older Adults: Mixed Method Study.

    PubMed

    Puri, Arjun; Kim, Ben; Nguyen, Olivier; Stolee, Paul; Tung, James; Lee, Joon

    2017-11-15

    Wearable activity trackers are newly emerging technologies with the anticipation for successfully supporting aging-in-place. Consumer-grade wearable activity trackers are increasingly ubiquitous in the market, but the attitudes toward, as well as acceptance and voluntary use of, these trackers in older population are poorly understood. The aim of this study was to assess acceptance and usage of wearable activity trackers in Canadian community-dwelling older adults, using the potentially influential factors as identified in literature and technology acceptance model. A mixed methods design was used. A total of 20 older adults aged 55 years and older were recruited from Southwestern Ontario. Participants used 2 different wearable activity trackers (Xiaomi Mi Band and Microsoft Band) separately for each segment in the crossover design study for 21 days (ie, 42 days total). A questionnaire was developed to capture acceptance and experience at the end of each segment, representing 2 different devices. Semistructured interviews were conducted with 4 participants, and a content analysis was performed. Participants ranged in age from 55 years to 84 years (mean age: 64 years). The Mi Band gained higher levels of acceptance (16/20, 80%) compared with the Microsoft Band (10/20, 50%). The equipment characteristics dimension scored significantly higher for the Mi Band (P<.05). The amount a participant was willing to pay for the device was highly associated with technology acceptance (P<.05). Multivariate logistic regression with 3 covariates resulted in an area under the curve of 0.79. Content analysis resulted in the formation of the following main themes: (1) smartphones as facilitators of wearable activity trackers; (2) privacy is less of a concern for wearable activity trackers, (3) value proposition: self-awareness and motivation; (4) subjective norm, social support, and sense of independence; and (5) equipment characteristics matter: display, battery, comfort, and aesthetics. Older adults were mostly accepting of wearable activity trackers, and they had a clear understanding of its value for their lives. Wearable activity trackers were uniquely considered more personal than other types of technologies, thereby the equipment characteristics including comfort, aesthetics, and price had a significant impact on the acceptance. Results indicated that privacy was less of concern for older adults, but it may have stemmed from a lack of understanding of the privacy risks and implications. These findings add to emerging research that investigates acceptance and factors that may influence acceptance of wearable activity trackers among older adults. ©Arjun Puri, Ben Kim, Olivier Nguyen, Paul Stolee, James Tung, Joon Lee. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 15.11.2017.

  20. Combinations of 148 navigation stars and the star tracker

    NASA Technical Reports Server (NTRS)

    Duncan, R.

    1980-01-01

    The angular separation of all star combinations for 148 nav star on the onboard software for space transportation system-3 flight and following missions is presented as well as the separation of each pair that satisfies the viewing constraints of using both star trackers simultaneously. Tables show (1) shuttle star catalog 1980 star position in M 1950 coordinates; (2) two star combination of 148 nav stars; and (3) summary of two star-combinations of the star tracker 5 deg filter. These 148 stars present 10,875 combinations. For the star tracker filters of plus or minus 5 deg, there are 875 combinations. Formalhaut (nav star 26) has the best number of combinations, which is 33.

  1. Microenvironment Tracker (MicroTrac) | Science Inventory ...

    EPA Pesticide Factsheets

    Epidemiologic studies have shown associations between air pollution concentrations measured at central-site ambient monitors and adverse health outcomes. Using central-site concentrations as exposure surrogates, however, can lead to exposure errors due to time spent in various indoor and outdoor microenvironments (ME) with pollutant concentrations that can be substantially different from central-site concentrations. These exposure errors can introduce bias and incorrect confidence intervals in health effect estimates, which diminish the power of such studies to establish correct conclusions about the exposure and health effects association. The significance of this issue was highlighted in the National Research Council (NRC) Report “Research Priorities for Airborne Particulate Matter”, which recommends that EPA address exposure error in health studies. To address this limitation, we developed MicroTrac, an automated classification model that estimates time of day and duration spent in eight ME (indoors and outdoors at home, work, school; inside vehicles; other locations) from personal global positioning system (GPS) data and geocoded boundaries of buildings (e.g., home, work, school). MicroTrac has several innovative design features: (1) using GPS signal quality to account for GPS signal loss inside certain buildings, (2) spatial buffering of building boundaries to account for the spatial inaccuracy of the GPS device, and (3) temporal buffering of GPS positi

  2. Gamma compensated, self powered neutron detector

    DOEpatents

    Brown, Donald P.

    1977-01-01

    An improved, self-powered, gamma compensated, neutron detector having two electrically conductive concentric cylindrical electrodes and a central rod emitter formed from a material which emits beta particles when bombarded by neutrons. The outer electrode and emitter are maintained at a common potential and the neutron representative current is furnished at the inner cylindrical electrode which serves as a collector. The two concentric cylindrical electrodes are designed to exhibit substantially equal electron emission induced by Compton scattering under neutron bombardment to supply the desired gamma compensation.

  3. Improved ion detector

    DOEpatents

    Tullis, A.M.

    1986-01-30

    An improved ion detector device of the ionization detection device chamber type comprises an ionization chamber having a central electrode therein surrounded by a cylindrical electrode member within the chamber with a collar frictionally fitted around at least one of the electrodes. The collar has electrical contact means carried in an annular groove in an inner bore of the collar to contact the outer surface of the electrode to provide electrical contact between an external terminal and the electrode without the need to solder leads to the electrode.

  4. Beyond al-Qaeda. Part 2. The Outer Rings of the Terrorist Universe

    DTIC Science & Technology

    2006-01-01

    Islam, it is possible for all followers of different religions to live in peace and with security over their person, property, and rights. In the...the third-largest religion in South Africa (after Protestant and Catholic). Thus, Muslims are a significant part of South African society—a central...Trying Times for Islamists,” Al-Ahram Weekly Online, January 10–16, 2002. De Silva, K. M., Religion , Nationalism and the State in Modern Sri Lanka, Tampa

  5. Dust to planetesimals - Settling and coagulation in the solar nebula

    NASA Technical Reports Server (NTRS)

    Weidenschilling, S. J.

    1980-01-01

    The behavior of solid particles in a low-mass solar nebula during settling to the central plane and the formation of planetesimals is discussed. The gravitational instability in a dust layer and collisional accretion are examined as possible mechanisms of planetesimal formation. The shear between the gas and a dust layer is considered along with the differences in the planetesimal formation mechanisms between the inner and outer nebula. A numerical model for computing simultaneous coagulation and settling is described.

  6. Three mirror glancing incidence system for X-ray telescope

    NASA Technical Reports Server (NTRS)

    Hoover, R. B. (Inventor)

    1974-01-01

    A telescope suitable for soft X-ray astronomical observations consists of a paraboloid section for receiving rays at a grazing angle and a hyperboloid section which receives reflections from the paraboloid at a grazing angle and directs them to a predetermined point of focus. A second hyperboloid section is centrally located from the other two surfaces and positioned to reflect from its outer surface radiation which was not first reflected by the paraboloid. A shutter is included to assist in calibration.

  7. Computational and experimental study of atmospheric moisture in ceramic blocks filled with waste fibres in winter season

    NASA Astrophysics Data System (ADS)

    Stastnik, S.

    2016-06-01

    Development of materials for vertical outer building structures tends to application of hollow clay blocks filled with some appropriate insulation material. Ceramic fittings provide high thermal resistance, but the walls built from them suffer from condensation of air humidity in winter season frequently. The paper presents the computational simulation and experimental laboratory validation of moisture behaviour of such masonry with insulation prepared from waste fibres under the Central European climatic conditions.

  8. Nuclear reactor fuel element

    DOEpatents

    Johnson, Carl E.; Crouthamel, Carl E.

    1980-01-01

    A nuclear reactor fuel element is described which has an outer cladding, a central core of fissionable or mixed fissionable and fertile fuel material and a layer of oxygen gettering material on the inner surface of the cladding. The gettering material reacts with oxygen released by the fissionable material during irradiation of the core thereby preventing the oxygen from reacting with and corroding the cladding. Also described is an improved method for coating the inner surface of the cladding with a layer of gettering material.

  9. Robust Visual Tracking Revisited: From Correlation Filter to Template Matching.

    PubMed

    Liu, Fanghui; Gong, Chen; Huang, Xiaolin; Zhou, Tao; Yang, Jie; Tao, Dacheng

    2018-06-01

    In this paper, we propose a novel matching based tracker by investigating the relationship between template matching and the recent popular correlation filter based trackers (CFTs). Compared to the correlation operation in CFTs, a sophisticated similarity metric termed mutual buddies similarity is proposed to exploit the relationship of multiple reciprocal nearest neighbors for target matching. By doing so, our tracker obtains powerful discriminative ability on distinguishing target and background as demonstrated by both empirical and theoretical analyses. Besides, instead of utilizing single template with the improper updating scheme in CFTs, we design a novel online template updating strategy named memory, which aims to select a certain amount of representative and reliable tracking results in history to construct the current stable and expressive template set. This scheme is beneficial for the proposed tracker to comprehensively understand the target appearance variations, recall some stable results. Both qualitative and quantitative evaluations on two benchmarks suggest that the proposed tracking method performs favorably against some recently developed CFTs and other competitive trackers.

  10. Chemoreception of hunger levels alters the following behaviour of a freshwater snail.

    PubMed

    Larcher, Marie; Crane, Adam L

    2015-12-01

    Chemically-mediated orientation is essential for many animals that must locate sites containing resources such as mates or food. One way to find these areas is by using publically-available information from other individuals. We tested a freshwater snail, Physa gyrina, for chemoreception of conspecific cues and predicted they could discriminate between cues based on information regarding hunger levels. We placed 'tracker' snails into a 2-arm arena where they could either follow or avoid an area previously used by a 'marker' snail. The hunger levels of both trackers and markers was manipulated, being either starved or fed. Starved and fed trackers did not differ in their following response when markers were hungry, but starved trackers were significantly more likely to follow fed markers, compared to fed trackers that tended to avoid areas used by fed markers. This outcome suggests that P. gyrina uses conspecific chemical cues to find food and potentially in some situations to avoid intra-specific food competition. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Star tracker operation in a high density proton field

    NASA Technical Reports Server (NTRS)

    Miklus, Kenneth J.; Kissh, Frank; Flynn, David J.

    1993-01-01

    Algorithms that reject transient signals due to proton effects on charge coupled device (CCD) sensors have been implemented in the HDOS ASTRA-l Star Trackers to be flown on the TOPEX mission scheduled for launch in July 1992. A unique technique for simulating a proton-rich environment to test trackers is described, as well as the test results obtained. Solar flares or an orbit that passes through the South Atlantic Anomaly can subject the vehicle to very high proton flux levels. There are three ways in which spurious proton generated signals can impact tracker performance: the many false signals can prevent or extend the time to acquire a star; a proton-generated signal can compromise the accuracy of the star's reported magnitude and position; and the tracked star can be lost, requiring reacquisition. Tests simulating a proton-rich environment were performed on two ASTRA-1 Star Trackers utilizing these new algorithms. There were no false acquisitions, no lost stars, and a significant reduction in reported position errors due to these improvements.

  12. A Unix SVR-4-OS9 distributed data acquisition for high energy physics

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

    Drouhin, F.; Schwaller, B.; Fontaine, J.C.

    1998-08-01

    The distributed data acquisition (DAQ) system developed by the GRPHE (Groupe de Recherche en Physique des Hautes Energies) group is a combination of hardware and software dedicated to high energy physics. The system described here is used in the beam tests of the CMs tracker. The central processor of the system is a RISC CPU hosted in a VME card, running a POSIX compliant UNIX system. Specialized real-time OS9 VME cards perform the instrumentation control. The main data flow goes over a deterministic high speed network. The Unix system manages a list of OS9 front-end systems with a synchronization protocolmore » running over a TCP/IP layer.« less

  13. Utilizing Maximum Power Point Trackers in Parallel to Maximize the Power Output of a Solar (Photovoltaic) Array

    DTIC Science & Technology

    2012-12-01

    photovoltaic (PV) system to use a maximum power point tracker ( MPPT ) to increase... photovoltaic (PV) system to use a maximum power point tracker ( MPPT ) to increase the power output of the solar array. Currently, most military... MPPT ) is an optimizing circuit that is used in conjunction with photovoltaic (PV) arrays to achieve the maximum delivery of power from the array

  14. A Methodology to Analyze Photovoltaic Tracker Uptime

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

    Muller, Matthew T; Ruth, Dan

    A metric is developed to analyze the daily performance of single-axis photovoltaic (PV) trackers. The metric relies on comparing correlations between the daily time series of the PV power output and an array of simulated plane-of-array irradiances for the given day. Mathematical thresholds and a logic sequence are presented, so the daily tracking metric can be applied in an automated fashion on large-scale PV systems. The results of applying the metric are visually examined against the time series of the power output data for a large number of days and for various systems. The visual inspection results suggest that overall,more » the algorithm is accurate in identifying stuck or functioning trackers on clear-sky days. Visual inspection also shows that there are days that are not classified by the metric where the power output data may be sufficient to identify a stuck tracker. Based on the daily tracking metric, uptime results are calculated for 83 different inverters at 34 PV sites. The mean tracker uptime is calculated at 99% based on 2 different calculation methods. The daily tracking metric clearly has limitations, but as there is no existing metrics in the literature, it provides a valuable tool for flagging stuck trackers.« less

  15. Use of a Remote Eye-Tracker for the Analysis of Gaze during Treadmill Walking and Visual Stimuli Exposition.

    PubMed

    Serchi, V; Peruzzi, A; Cereatti, A; Della Croce, U

    2016-01-01

    The knowledge of the visual strategies adopted while walking in cognitively engaging environments is extremely valuable. Analyzing gaze when a treadmill and a virtual reality environment are used as motor rehabilitation tools is therefore critical. Being completely unobtrusive, remote eye-trackers are the most appropriate way to measure the point of gaze. Still, the point of gaze measurements are affected by experimental conditions such as head range of motion and visual stimuli. This study assesses the usability limits and measurement reliability of a remote eye-tracker during treadmill walking while visual stimuli are projected. During treadmill walking, the head remained within the remote eye-tracker workspace. Generally, the quality of the point of gaze measurements declined as the distance from the remote eye-tracker increased and data loss occurred for large gaze angles. The stimulus location (a dot-target) did not influence the point of gaze accuracy, precision, and trackability during both standing and walking. Similar results were obtained when the dot-target was replaced by a static or moving 2D target and "region of interest" analysis was applied. These findings foster the feasibility of the use of a remote eye-tracker for the analysis of gaze during treadmill walking in virtual reality environments.

  16. Contradictions in digital health engagement: An activity tracker's ambiguous influence on vulnerable young adults' engagement in own health.

    PubMed

    Kanstrup, Anne Marie; Bertelsen, Pernille; Jensen, Martin B

    2018-01-01

    Activity trackers are designed to support individuals in monitoring and increasing their physical activity. The use of activity trackers among individuals diagnosed with depression and anxiety has not yet been examined. This pilot study investigates how this target group engages with an activity tracker during a 10-week health intervention aimed to increase their physical activity level and improve their physical and mental health. Two groups of 11 young adults (aged 18-29 years) diagnosed with depression or anxiety participated in the digital health intervention. The study used mixed methods to investigate the research question. Quantitative health data were used to assess the intervention's influence on the participants' health and qualitative data provided insights into the participants' digital health experience. The study demonstrated an ambiguous influence from the use of an activity tracker with positive physical and mental health results, but a fading and even negative digital health engagement and counterproductive competition. The ambiguous results identify a need for (1) developing strategies for health professionals to provide supervised use of activity trackers and support the target groups' abilities to convert health information about physical activity into positive health strategies, and (2) designing alternatives for health promoting IT targeted users who face challenges and need motivation beyond self-tracking and competition.

  17. Star Tracker Performance Estimate with IMU

    NASA Technical Reports Server (NTRS)

    Aretskin-Hariton, Eliot D.; Swank, Aaron J.

    2015-01-01

    A software tool for estimating cross-boresight error of a star tracker combined with an inertial measurement unit (IMU) was developed to support trade studies for the Integrated Radio and Optical Communication project (iROC) at the National Aeronautics and Space Administration Glenn Research Center. Typical laser communication systems, such as the Lunar Laser Communication Demonstration (LLCD) and the Laser Communication Relay Demonstration (LCRD), use a beacon to locate ground stations. iROC is investigating the use of beaconless precision laser pointing to enable laser communication at Mars orbits and beyond. Precision attitude knowledge is essential to the iROC mission to enable high-speed steering of the optical link. The preliminary concept to achieve this precision attitude knowledge is to use star trackers combined with an IMU. The Star Tracker Accuracy (STAcc) software was developed to rapidly assess the capabilities of star tracker and IMU configurations. STAcc determines the overall cross-boresight error of a star tracker with an IMU given the characteristic parameters: quantum efficiency, aperture, apparent star magnitude, exposure time, field of view, photon spread, detector pixels, spacecraft slew rate, maximum stars used for quaternion estimation, and IMU angular random walk. This paper discusses the supporting theory used to construct STAcc, verification of the program and sample results.

  18. Tracker-assisted versus manual ablation zone centration in laser in situ keratomileusis for myopia and astigmatism.

    PubMed

    Pineros, Oscar E

    2002-01-01

    Eye tracker systems have been developed concomitantly with small scanning beams to theoretically reduce ablation zone decentration and for accurate registration of all the laser pulses on the cornea. The purpose of the study was to compare the tracker-assisted with the manual centration method. Twenty-five patients (48 eyes) with myopia and/or astigmatism had laser in situ keratomileusis (LASIK) between August 1998 and February 1999 with the Technolas 117C laser. Twenty patients (38 eyes, 80%) were available for follow-up at 3 months after surgery. Eyes were assigned randomly to one of two ablation zone centration methods: Group 1: Tracker-assisted (20 eyes), Group 2: Manual (18 eyes). Mean distance between the ablation zone center and the pupillary center in the tracker-assisted centration group was 0.55 +/- 0.30 mm (range, 0.10 to 1.4 mm), and in the manual centration group, 0.43 +/- 0.23 mm (range, 0.10 to 1.0 mm) (P = .177). There was no statistically significant difference in postoperative contrast sensitivity, glare, and Topographical Corneal Surface Regularity Index (SRI) between the two groups. We obtained good results with both centration methods. We did not find superiority of the tracker-assisted over manual regarding ablation zone centration, vision quality, or regularity of the ablation.

  19. Using CarbonTracker carbon flux estimates to improve a terrestrial carbon cycle model

    NASA Astrophysics Data System (ADS)

    Peters, W.; Krol, M.; Miller, J. B.; Tans, P. P.; Carvalhais, N.; Schaefer, K.

    2009-12-01

    Estimates of net ecosystem exchange (NEE) from NOAA’s CarbonTracker CO2 data assimilation system show patterns of annual net uptake not represented in most terrestrial carbon cycle models. This is mainly because such models lack information on the land-use history of individual ecosystems, which is the main driver of long-term mean carbon exchange. Instead, they assume the biosphere to be in steady-state, with annual gross photosynthesis equalling ecosystem respiration everywhere. This limits their use in interpreting observations of carbon dynamics such as with eddy-covariance techniques or through atmospheric CO2 records. We have implemented a method that takes the long-term mean NEE estimates from CarbonTracker to derive the size of the dominant carbon pool in each ecosystem of the SIBCASA biosphere model. With the new pool sizes, the SIBCASA model is no longer in steady-state and reproduces annual carbon uptake patterns from CarbonTracker. We will show that the non steady-state SIBCASA model is not only much more consistent with the atmospheric CO2 record, but also with independent data on standing wood biomass and forest age from the Forest Inventory and Analysis (FIA) Program of the U.S. Forest Service. Four years of CarbonTracker NEE are needed to reliably derive a long term mean for this process, and we use three other years from CarbonTracker to evaluate the non steady state SIBCASA NEE. We will furthermore show that the non steady-state SIBCASA NEE is a much better first-guess for the CarbonTracker data assimilation process, allowing more confidence in its final NEE estimate, and reducing a systematic bias in CarbonTracker modeled atmospheric CO2. This overcomes a long standing issue in inverse modeling, and opens the way for further assessment and improvement of carbon cycle models such as SIBCASA.

  20. Youth Oriented Activity Trackers: Comprehensive Laboratory- and Field-Based Validation

    PubMed Central

    2017-01-01

    Background Commercial activity trackers are growing in popularity among adults and some are beginning to be marketed to children. There is, however, a paucity of independent research examining the validity of these devices to detect physical activity of different intensity levels. Objectives The purpose of this study was to determine the validity of the output from 3 commercial youth-oriented activity trackers in 3 phases: (1) orbital shaker, (2) structured indoor activities, and (3) 4 days of free-living activity. Methods Four units of each activity tracker (Movband [MB], Sqord [SQ], and Zamzee [ZZ]) were tested in an orbital shaker for 5-minutes at three frequencies (1.3, 1.9, and 2.5 Hz). Participants for Phase 2 (N=14) and Phase 3 (N=16) were 6-12 year old children (50% male). For Phase 2, participants completed 9 structured activities while wearing each tracker, the ActiGraph GT3X+ (AG) research accelerometer, and a portable indirect calorimetry system to assess energy expenditure (EE). For Phase 3, participants wore all 4 devices for 4 consecutive days. Correlation coefficients, linear models, and non-parametric statistics evaluated the criterion and construct validity of the activity tracker output. Results Output from all devices was significantly associated with oscillation frequency (r=.92-.99). During Phase 2, MB and ZZ only differentiated sedentary from light intensity (P<.01), whereas the SQ significantly differentiated among all intensity categories (all comparisons P<.01), similar to AG and EE. During Phase 3, AG counts were significantly associated with activity tracker output (r=.76, .86, and .59 for the MB, SQ, and ZZ, respectively). Conclusions Across study phases, the SQ demonstrated stronger validity than the MB and ZZ. The validity of youth-oriented activity trackers may directly impact their effectiveness as behavior modification tools, demonstrating a need for more research on such devices. PMID:28724509

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