Now showing items 17096-17115 of 17837

    • The V1647 Orionis (IRAS 05436–0007) Protostar and Its Environment 

      McGehee, Peregrine M.; Smith, J. Allyn; Henden, Arne A.; Richmond, Michael W.; Knapp, Gillian R.; Finkbeiner, Douglas; Ivezic, Zeljko; Brinkmann, J. (IOP Publishing, 2004)
      We present Sloan Digital Sky Survey (SDSS) and United States Naval Observatory (USNO) observations of the V1647 Ori protostar and its surrounding field near NGC 2068. V1647 Ori, the likely driving source for HH 23, brightened ...
    • Vacancy in Silicon Revisited: Structure and Pressure Effects 

      Antonelli, A.; Kaxiras, Efthimios; Chadi, D. (American Physical Society, 1998)
      The structure of the single vacancy in silicon. one of the most common point defects and an important mediator of atomic diffusion, is examined through extensive first principles calculations. We find a hitherto unexpected ...
    • Vaccination Rates are Associated With Functional Proximity But Not Base Proximity of Vaccination Clinics 

      Beshears, John Leonard; Choi, James J.; Laibson, David I.; Madrian, Brigitte; Reynolds, Gwendolyn I. (Ovid Technologies (Wolters Kluwer Health), 2016)
      Background: Routine annual influenza vaccinations are recommended for persons 6 months of age and older, but less than half of US adults get vaccinated. Many employers offer employees free influenza vaccinations at ...
    • Vacuum Decay Constraints on a Cosmological Scalar Field 

      Heyl, Jeremy S.; Loeb, Abraham (American Physical Society, 2002)
      If the potential of a scalar filed phi which currently provides the dark energy of the Universe has a minimum at phi = -M-0(4) < 0, then quantum-mechanical fluctuations could nucleate a bubble of φ at a negative ...
    • Vacuum Instabilities with a Wrong-Sign Higgs-Gluon-Gluon Amplitude 

      Reece, Matthew (IOP Publishing, 2013-03-19)
      The recently discovered 125 GeV boson appears very similar to a Standard Model Higgs, but with data favoring an enhanced \(h \rightarrow \gamma \gamma\) rate. A number of groups have found that fits would allow (or, less ...
    • Vacuum states for AdS2 black holes 

      Spradlin, Marcus; Strominger, Andrew (Springer Verlag, 1999)
      An AdS(2) black hole spacetime is an AdS(2) spacetime together with a preferred choice of time. The Boulware, Hartle-Hawking and SL(2; R) invariant vacua are constructed, together with their Green functions and stress ...
    • Valence Bond Solid Order Near Impurities in Two-Dimensional Quantum Antiferromagnets 

      Metlitski, Max A.; Sachdev, Subir (American Physical Society, 2008)
      Recent scanning tunneling microscopy (STM) experiments on underdoped cuprates have displayed modulations in the local electronic density of states, which are centered on a Cu-O-Cu bond [Kohsaka et al. Science 315 1380 ...
    • Validation of 10-year SAO OMI Ozone Profile (PROFOZ) Product Using Ozonesonde Observations 

      Huang, Guanyu; Liu, Xiong; Chance, Kelly V.; Yang, Kai; Bhartia, Pawan K.; Cai, Zhaonan; Allaart, Marc; Calpini, Bertrand; Coetzee, Gerrie J. R.; Cuevas-Agulló, Emilio; Cupeiro, Manuel; De Backer, Hugo; Dubey, Manvendra K.; Fuelberg, Henry E.; Fujiwara, Masatomo; Godin-Beekmann, Sophie; Hall, Tristan J.; Johnson, Bryan; Joseph, Everette; Kivi, Rigel; Kois, Bogumil; Komala, Ninong; König-Langlo, Gert; Laneve, Giovanni; Leblanc, Thierry; Marchand, Marion; Minschwaner, Kenneth R.; Morris, Gary; Newchurch, Mike J.; Ogino, Shin-Ya; Ohkawara, Nozomu; Piters, Ankie J. M.; Posny, Françoise; Querel, Richard; Scheele, Rinus; Schmidlin, Frank J.; Schnell, Russell C.; Schrems, Otto; Selkirk, Henry; Shiotani, Masato; Skrivánková, Pavla; Stübi, René; Taha, Ghassan; Tarasick, David W.; Thompson, Anne M.; Thouret, Valérie; Tully, Matt; van Malderen, Roeland; Vaughan, Geraint; Vömel, Holger; von der Gathen, Peter; Witte, Jacquelyn C.; Yela, Margarita (Copernicus GmbH, 2017)
      We validate the Ozone Monitoring Instrument (OMI) ozone-profile (PROFOZ) product from October 2004 through December 2014 retrieved by the Smithsonian Astrophysical Observatory (SAO) algorithm against ozonesonde observations. ...
    • Validation of a non-invasive model for predicting long bone loading 

      Polk, John D.; Lieberman, Daniel; Betz, Amy E.; Demes, Brigitte (Oxford University Press, 2005)
      Functional interpretation of limb bone cross-sectional geometry depends upon knowledge of the magnitude and direction of habitual loading. Quantification of bone loading has only been possible using invasive, in vivo strain ...
    • Validation of a non-invasive model for predicting long bone loading 

      Polk, John D.; Lieberman, Daniel; Betz, Amy E.; Demes, Brigitte (John Wiley & Sons, 2005)
      Functional interpretation of limb bone cross-sectional geometry depends upon knowledge of the magnitude and direction of habitual loading. Quantification of bone loading has only been possible using invasive, in vivo strain ...
    • Validation of Hill-Type Muscle Models in Relation to Neuromuscular Recruitment and Force-Velocity Properties: Predicting Patterns of In Vivo Muscle Force 

      Biewener, Andrew Austin; Wakeling, James; Lee, Sabrina S.; Arnold, Allison (Oxford University Press (OUP), 2014)
      We review here the use and reliability of Hill-type muscle models to predict muscle performance under varying conditions, ranging from in situ production of isometric force to in vivo dynamics of muscle length change and ...
    • Validation of Multiangle Imaging Spectroradiometer (MISR) aerosol optical thickness measurements using Aerosol Robotic Network (AERONET) observations over the contiguous United States 

      Liu, Yang; Sarnat, Jeremy; Coull, Brent Andrew; Koutrakis, Petros; Jacob, Daniel James (Wiley-Blackwell, 2004)
      Aerosol optical thickness (AOT) data retrieved by the Multiangle Imaging Spectroradiometer (MISR) in 2001 were compared with AOT measurements from 16 Aerosol Robotic Network (AERONET) sites over the contiguous United States. ...
    • Validation of OMI Tropospheric NO2 Observations During INTEX-B and Application to Constrain NOx Emissions Over the Eastern United States and Mexico 

      Boersma, K.F.; Jacob, Daniel J.; Bucsela, E.J.; Perring, A.E.; Dirksen, R.; van der A, R.J.; Yantosca, Robert M.; Park, R.J.; Wenig, M.O.; Bertram, T.H.; Cohen, R.C. (Elsevier, 2008)
      We compare tropospheric NO2 column measurements from the Ozone Monitoring Instrument (OMI) aboard the EOS Aura satellite with coincident in situ aircraft measurements on vertical spirals over the southern United States, ...
    • Validation of TES Methane with HIPPO Aircraft Observations: Implications for Inverse Modeling of Methane Sources 

      Wecht, Kevin James; Jacob, Daniel J.; Wofsy, Steven C.; Kort, E. A.; Worden, J. R.; Kulawik, S. S.; Henze, D. K.; Kopacz, M.; Payne, V. H. (Copernicus GmbH, 2012)
      We validate satellite methane observations from the Tropospheric Emission Spectrometer (TES) with 151 aircraft vertical profiles over the Pacific from the HIAPER Pole-to-Pole Observation (HIPPO) program. We find that a ...
    • Validation of the Orthogonal Tilt Reconstruction Method with a Biological Test Sample 

      Chandramouli, Preethi; Hernandez-Lopez, Rogelio Antonio; Wang, Hong-Wei; Leschziner, Andres (Elsevier, 2011)
      Electron microscopy of frozen-hydrated samples (cryo-EM) can yield high resolution structures of macromolecular complexes by accurately determining the orientation of large numbers of experimental views of the sample ...
    • Validation of Urban \(NO_2\) Concentrations and Their Diurnal and Seasonal Variations Observed from the SCIAMACHY and OMI Sensors Using In Situ Surface Measurements in Israeli Cities 

      Boersma, K. F.; Jacob, Daniel James; Trainic, M.; Rudich, Y.; DeSmedt, I.; Dirksen, R.; Eskes, H. J. (European Geosciences Union, 2009)
      We compare a full-year (2006) record of surface air \(NO_2\) concentrations measured in Israeli cities to coinciding retrievals of tropospheric \(NO_2\) columns from satellite sensors (SCIAMACHY aboard ENVISAT and OMI ...
    • Validity of the salience asymmetry interpretation of the Implicit Association Test: Comment on Rothermund and Wentura (2004). 

      Greenwald, Anthony G.; Nosek, Brian A.; Banaji, Mahzarin; Klauer, K. Christoph (American Psychological Association (APA), 2005)
      The Implicit Association Test (IAT) requires responding to category contrasts such as young versus old, male versus female, and pleasant versus unpleasant. In introducing the IAT, A. G. Greenwald, D. E. McGhee, and J. L. ...
    • Valproate reopens critical-period learning of absolute pitch 

      Gervain, Judit; Vines, Bradley W.; Chen, Lawrence M.; Seo, Rubo J.; Hensch, Takao K.; Werker, Janet F.; Young, Allan H. (Frontiers Media S.A., 2013)
      Absolute pitch, the ability to identify or produce the pitch of a sound without a reference point, has a critical period, i.e., it can only be acquired early in life. However, research has shown that histone-deacetylase ...
    • Value of Medical Innovation in the United States: 1960-2000 

      Cutler, David; Rosen, Allison B.; Vijan, Sandeep (Massachusetts Medical Society, 2006)
      Background: The increased use of medical therapies has led to increased medical costs. To provide insight into the value of this increased spending, we compared gains in life expectancy with the increased costs of care ...
    • The Value of Postsecondary Credentials in the Labor Market: An Experimental Study 

      Deming, David James; Yuchtman, Noam; Abulafi, Amira; Goldin, Claudia D.; Katz, Lawrence F. (American Economic Association, 2016)
      We study employers’ perceptions of the value of postsecondary degrees using a field experiment. We randomly assign the sector and selectivity of institutions to fictitious resumes and apply to real vacancy postings for ...