Browsing FAS Scholarly Articles by Title

Now showing items 21-40 of 18153

    • 230 GHz VLBI observations of M87: event-horizon-scale structure at the enhanced very-high-energy γ-ray state in 2012 

      Akiyama, Kazunori; Lu, Ru-Sen; Fish, Vincent; Doeleman, Sheperd S.; Broderick, Avery; Dexter, Jason; Hada, Kazuhiro; Kino, Motoki; Nagai, Hiroshi; Honma, Mareki; Johnson, Michael D.; Algaba, Juan; Asada, Keiichi; Brinkerink, Christiaan; Blundell, Raymond; Bower, Geoffrey; Cappallo, Roger; Crew, Geoffrey; Dexter, Matt; Dzib, Sergio; Freund, Robert; Friberg, Per; Gurwell, Mark Andrew; Ho, Paul; Inoue, Makoto; Krichbaum, Thomas; Loinard, Laurent; MacMahon, David; Marrone, Daniel; Moran, James M.; Nakamura, Masanori; Nagar, Neil; Ortiz-Leon, Gisela; Plambeck, Richard; Pradel, Nicolas; Primiani, Rurik A.; Rogers, Alan; Roy, Alan; SooHoo, Jason; Tavares, Jonathan-León; Tilanus, Remo; Titus, Michael; Wagner, Jan; Weintroub, Jonathan; Yamaguchi, Paul Isami; Young, Ken Harbour; Zensus, Anton; Ziurys, Lucy (IOP Publishing, 2015)
      We report on 230 GHz (1.3 mm) VLBI observations of M87 with the Event Horizon Telescope using antennas on Mauna Kea in Hawaii, Mt. Graham in Arizona and Cedar Flat in California. For the first time, we have acquired 230 ...

    • 25th Anniversary Article: A Soft Future: From Robots and Sensor Skin to Energy Harvesters 

      Bauer, Siegfried; Bauer-Gogonea, Simona; Graz, Ingrid; Kaltenbrunner, Martin; Keplinger, Christoph; Schwödiauer, Reinhard (BlackWell Publishing Ltd, 2013)
      Scientists are exploring elastic and soft forms of robots, electronic skin and energy harvesters, dreaming to mimic nature and to enable novel applications in wide fields, from consumer and mobile appliances to biomedical ...

    • 2D Kac-Moody symmetry of 4D Yang-Mills theory 

      He, Temple; Mitra, Prahar; Strominger, Andrew (Springer Verlag, 2016)
      Scattering amplitudes of any four-dimensional theory with nonabelian gauge group G may be recast as two-dimensional correlation functions on the asymptotic two-sphere at null in finity. The soft gluon theorem is shown, for ...

    • 2D-Shape Analysis Using Conformal Mapping 

      Sharon, E.; Mumford, David Bryant (Springer Verlag, 2006)
      The study of 2D shapes and their similarities is a central problem in the field of vision. It arises in particular from the task of classifying and recognizing objects from their observed silhouette. Defining natural ...

    • (2×2) Reconstructions of the {111} Polar Surfaces of GaAs 

      Kaxiras, Efthimios; Bar-Yam, Yaneer; Joannopoulos, John D.; Pandey, K.C. (American Physical Society, 1986)
      Ab initio total-energy calculations were used to examine (2×2) reconstruction models for the (111) and (1¯1¯1¯) surfaces of GaAs. For the (111) surface the lowest-energy Ga-vacancy geometry is determined; several mechanisms ...

    • 3 W Continuous-Wave Room Temperature Single-Facet Emission From Quantum Cascade Lasers Based On Nonresonant Extraction Design Approach 

      Lyakh, Arkadiy; Maulini, Richard; Tsekoun, Alexei; Go, Rowel; Pflügl, Christian; Diehl, Laurent; Wang, Qi Jie; Capasso, Federico; Patel, C. Kumar N. (American Institute of Physics, 2009)
      A strain-balanced, InP-based quantum cascade laser structure, designed for light emission at 4.6 \(\mu\)m using a new nonresonant extraction design approach, was grown by molecular beam epitaxy. Removal of the restrictive ...

    • 3-Cm Fine Structure Masers: A Unique Signature of Supermassive Black Hole Formation via Direct Collapse in the Early Universe 

      Dijkstra, Mark; Sethi, Shiv; Loeb, Abraham (American Astronomical Society, 2016)
      The direct collapse black hole (DCBH) scenario describes the isothermal collapse of a pristine gas cloud directly into a massive, M_BH=10^4-10^6 M_sun black hole. In this paper we show that large HI column densities of ...

    • 30,000 Years Old Wild Flax Fibers - Testimony for Fabricating Prehistoric Linen 

      Kvavadze, Eliso; Bar-Yosef, Ofer; Belfer-Cohen, Anna; Boaretto, Elisabetta; Jakeli, Nino; Matskevich, Zinovi; Meshveliani, Tengiz (American Association for the Advancement of Science, 2009)
      A unique finding of wild flax fibers from a series of Upper Paleolithic layers at Dzudzuana Cave, located in the foothills of the Caucasus, Georgia, indicates that prehistoric hunter-gatherers were making cords for hafting ...

    • 3264 and all that 

      Eisenbud, David; Harris, Joseph D. (Cambridge University Press, 2016)

    • 3c 220.3: A Radio Galaxy Lensing a Submillimeter Galaxy 

      Haas, Martin; Leipski, Christian; Barthel, Peter; Wilkes, Belinda Jane; Vegetti, Simona; Bussmann, R. Shane; Willner, Steven P.; Westhues, Christian; Ashby, Matthew L N; Chini, Rolf; Clements, David L.; Fassnacht, Christopher D.; Horesh, Assaf; Klaas, Ulrich; Koopmans, Léon V. E.; Kuraszkiewicz, Joanna; Lagattuta, David J.; Meisenheimer, Klaus; Stern, Daniel; Wylezalek, Dominika (IOP Publishing, 2014)
      Herschel Space Observatory photometry and extensive multiwavelength follow-up have revealed that the powerful radio galaxy (PRG) 3C 220.3 at z = 0.685 acts as a gravitational lens for a background submillimeter galaxy (SMG) ...

    • 3D Axon Structure Extraction and Analysis in Confocal Fluorescence Microscopy Images 

      Zhang, Yong; Zhou, Xiaobo; Lu, Ju; Lichtman, Jeff; Adjeroh, Donald; Wong, Stephen T. C. (Massachusetts Institute of Technology Press, 2008)
      The morphological properties of axons, such as their branching patterns and oriented structures, are of great interest for biologists in the study of the synaptic connectivity of neurons. In these studies, researchers use ...

    • 3D Bioprinting of Vascularized, Heterogeneous Cell-Laden Tissue Constructs 

      Kolesky, David Barry; Truby, Ryan Landon; Gladman, Amelia Sydney; Busbee, Travis Alexander; Homan, Kimberly A.; Lewis, Jennifer (Wiley-Blackwell, 2014)
      A new bioprinting method is reported for fabricating 3D tissue constructs replete with vasculature, multiple types of cells, and extracellular matrix. These intricate, heterogeneous structures are created by precisely ...

    • 3D climate modeling of close-in land planets: Circulation patterns, climate moist bistability, and habitability 

      Leconte, J.; Forget, F.; Charnay, B.; Wordsworth, Robin; Selsis, F.; Millour, E.; Spiga, A. (EDP Sciences, 2013)
      The inner edge of the classical habitable zone is often defined by the critical flux needed to trigger the runaway greenhouse instability. This 1D notion of a critical flux, however, may not be all that relevant for ...

    • 3D Deformation Using Moving Least Squares 

      Zhu, Yuanchen; Gortler, Steven J. (2007)
      We present a 3d deformation method based on Moving Least Squares that extends the work by Schaefer et al. [Schaefer et al. 2006] to the 3d setting. The user controls the deformation by manipulating a set of point handles. ...

    • 3D modelling of the climatic impact of outflow channel formation events on early Mars 

      Turbet, Martin; Forget, Francois; Head, James W.; Wordsworth, Robin (Elsevier BV, 2017)
      Mars was characterized by cataclysmic groundwater-sourced surface flooding that formed large outflow channels and that may have altered the climate for extensive periods during the Hesperian era. In particular, it has been ...

    • 3D modelling of the early martian climate under a denser \(CO_2\) atmosphere: Temperatures and \(CO_2\) ice clouds 

      Forget, F.; Wordsworth, Robin; Millour, E.; Madeleine, J.-B.; Kerber, L.; Leconte, J.; Marcq, E.; Haberle, R.M. (Elsevier BV, 2013)
      On the basis of geological evidence, it is often stated that the early martian climate was warm enough for liquid water to flow on the surface thanks to the greenhouse effect of a thick atmosphere. We present 3D global ...

    • 3D Multicolor Super-Resolution Imaging Offers Improved Accuracy in Neuron Tracing 

      Lakadamyali, Melike; Babcock, Hazen P.; Bates, Mark; Zhuang, Xiaowei; Lichtman, Jeff (Public Library of Science, 2012)
      The connectivity among neurons holds the key to understanding brain function. Mapping neural connectivity in brain circuits requires imaging techniques with high spatial resolution to facilitate neuron tracing and high ...

    • 3D Printing of Interdigitated Li-Ion Microbattery Architectures 

      Sun, Ke; Wei, Teng-Sing; Ahn, Bok Yeop; Seo, Jung Yoon; Dillon, Shen J.; Lewis, Jennifer (Wiley-Blackwell, 2013)
      3D interdigitated microbattery architectures (3D-IMA) are fabricated by printing concentrated lithium oxide-based inks. The microbatteries are composed of interdigitated, high-aspect ratio cathode and anode structures. Our ...

    • 3D Printing of Transparent and Conductive Heterogeneous Hydrogel-Elastomer Systems 

      Tian, Kevin; Bae, Jinhye; Bakarich, Shannon E.; Yang, Canhui; Gately, Reece D.; Spinks, Geoffrey M.; in het Panhuis, Marc; Suo, Zhigang; Vlassak, Joost J. (Wiley-Blackwell, 2017)
      Hydrogel-based ionic devices represent an alternative approach to stretchable electronics through use of soft ionic conductors that are both highly stretchable and transparent. However, these devices require the integration ...

    • 3D Printing Soft Materials: What Is Possible? 

      Trimmer, Barry; Lewis, Jennifer; Shepherd, Robert F.; Lipson, Hod (Mary Ann Liebert Inc, 2015)