550 research outputs found
The Fifth Column in Congress: Washington Merry-Go-Round - Congressman Day\u27s Book Linked to Nazi Agents, 1941
A typed flyer from the Fight for Freedom Committee promoting an article entitled, Washington Merry-Go-Round , written by Drew Pearson and Robert S. Allen, dating from circa 1941. Within, it is reported that isolationist congressman Stephen A. Day\u27s book was published by a company with ties to Nazi agents.https://digitalcommons.ursinus.edu/fmhw_secondworldwar_documents/1106/thumbnail.jp
Mid-infrared Hall effect in thin-film metals: Probing the Fermi surface anisotropy in Au and Cu
A sensitive mid-infrared (MIR, 900-1100 cm-1, 112-136 meV) photo-elastic
polarization modulation technique is used to measure simultaneously Faraday
rotation and circular dichroism in thin metal films. These two quantities
determine the complex AC Hall conductivity. This novel technique is applied to
study Au and Cu thin films at temperatures down to 20 K and magnetic fields up
to 8 T. The Hall frequency is consistent with band theory predictions. We
report the first measurement of the MIR Hall scattering rate, which is
significantly lower than that derived from Drude analysis of zero magnetic
field MIR transmission measurements. This difference is qualitatively explained
in terms of the anisotropy of the Fermi surface in Au and Cu.Comment: 14 pages of text, 5 figure
Temperature Dependence of Low-Lying Electronic Excitations of LaMnO_3
We report on the optical properties of undoped single crystal LaMnO_3, the
parent compound of the colossal magneto-resistive manganites. Near-Normal
incidence reflectance measurements are reported in the frequency range of
20-50,000 cm-1 and in the temperature range 10-300 K. The optical conductivity,
s_1(w), is derived by performing a Kramers-Kronig analysis of the reflectance
data. The far-infrared spectrum of s_1(w) displays the infrared active optical
phonons. We observe a shift of several of the phonon to high frequencies as the
temperature is lowered through the Neel temperature of the sample (T_N = 137
K). The high-frequency s_1(w) is characterized by the onset of absorption near
1.5 eV. This energy has been identified as the threshold for optical
transitions across the Jahn-Teller split e_g levels. The spectral weight of
this feature increases in the low-temperature state. This implies a transfer of
spectral weight from the UV to the visible associated with the paramagnetic to
antiferromagnetic state. We discuss the results in terms of the double exchange
processes that affect the optical processes in this magnetic material.Comment: 7 pages, 5 figure
Competition of charge, orbital, and ferromagnetic correlations in layered manganites
The competition of charge, orbital, and ferromagnetic interactions in layered
manganites is investigated by magneto-Raman scattering spectroscopy. We find
that the colossal magnetoresistance effect in the layered compounds results
from the interplay of the orbital and ferromagnetic double-exchange
correlations. Inelastic scattering by charge-order fluctuations dominates the
quasiparticle dynamics in the ferromagnetic-metal state. The scattering is
suppressed at low frequencies, consistent with the opening of a charge-density
wave pseudogap.Comment: 10 pages, 4 figure
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Continuing upward trend in Mt Read Huon pine ring widths – Temperature or divergence?
To date, no attempt has been made to assess the presence or otherwise of the “Divergence Problem” (DP) in existing multi-millennial Southern Hemisphere tree-ring chronologies. We have updated the iconic Mt Read Huon pine chronology from Tasmania, southeastern Australia, to now include the warmest decade on record, AD 2000–2010, and used the Kalman Filter (KF) to examine it for signs of divergence against four different temperature series available for the region. Ring-width growth for the past two decades is statistically unprecedented for the past 1048 years. Although we have identified a decoupling between temperature and growth in the past two decades, the relationship between some of the temperature records and growth has varied over time since the start of instrumental records. Rather than the special case of ‘divergence’, we have identified a more general time-dependence between growth and temperature over the last 100 years. This time-dependence appears particularly problematic at interdecadal time scales. Due to the time-dependent relationships, and uncertainties related to the climate data, the use of any of the individual temperature series examined here potentially complicates temperature reconstruction. Some of the uncertainty in the climate data may be associated with changing climatic conditions, such as the intensification of the sub-tropical ridge (STR) and its impact on the frequency of anticyclonic conditions over the Mt Read site. Increased growth at the site, particularly in the last decade, over and above what would be expected based on a linear temperature model alone, may be consistent with a number of hypotheses. Existing uncertainties in the climate data need to be resolved and independent physiological information obtained before a range of hypotheses for this increased growth can be effectively evaluated
New OB star candidates in the Carina Arm around Westerlund 2 from VPHAS+
Date of Acceptance: 10/04/2015O and early B stars are at the apex of galactic ecology, but in the Milky Way, only a minority of them may yet have been identified. We present the results of a pilot study to select and parametrise OB star candidates in the Southern Galactic plane, down to a limiting magnitude of . A 2 square-degree field capturing the Carina Arm around the young massive star cluster, Westerlund 2, is examined. The confirmed OB stars in this cluster are used to validate our identification method, based on selection from the diagram for the region. Our Markov Chain Monte Carlo fitting method combines VPHAS+ with published photometry in order to derive posterior probability distributions of the stellar parameters and distance modulus, together with the reddening parameters and . The stellar parameters are sufficient to confirm OB status while the reddening parameters are determined to a precision of and . There are 489 objects that fit well as new OB candidates, earlier than B2. This total includes 74 probable massive O stars, 5 likely blue supergiants and 32 reddened subdwarfs. This increases the number of previously known and candidate OB stars in the region by nearly a factor of 10. Most of the new objects are likely to be at distances between 3 and 6 kpc. We have confirmed the results of previous studies that, at these longer distances, these sight lines require non-standard reddening laws with $3.5R_VPeer reviewe
Raloxifene improves skeletal properties in an animal model of cystic chronic kidney disease
Patients with chronic kidney disease (CKD) have an increased risk of fracture. Raloxifene is a mild antiresorptive agent that reduces fracture risk in the general population. Here we assessed the impact of raloxifene on the skeletal properties of animals with progressive CKD. Male Cy/+ rats that develop autosomal dominant cystic kidney disease were treated with either vehicle or raloxifene for five weeks. They were assessed for changes in mineral metabolism and skeletal parameters (microCT, histology, whole-bone mechanics, and material properties). Their normal littermates served as controls. Animals with CKD had significantly higher parathyroid hormone levels compared with normal controls, as well as inferior structural and mechanical skeletal properties. Raloxifene treatment resulted in lower bone remodeling rates and higher cancellous bone volume in the rats with CKD. Although it had little effect on cortical bone geometry, it resulted in higher energy to fracture and modulus of toughness values than vehicle-treated rats with CKD, achieving levels equivalent to normal controls. Animals treated with raloxifene had superior tissue-level mechanical properties as assessed by nanoindentation, and higher collagen D-periodic spacing as assessed by atomic force microscopy. Thus, raloxifene can positively impact whole-bone mechanical properties in CKD through its impact on skeletal material properties
Seeing the way: visual sociology and the distance runner's perspective
Employing visual and autoethnographic data from a two‐year research project on distance runners, this article seeks to examine the activity of seeing in relation to the activity of distance running. One of its methodological aims is to develop the linkage between visual and autoethnographic data in combining an observation‐based narrative and sociological analysis with photographs. This combination aims to convey to the reader not only some of the specific subcultural knowledge and particular ways of seeing, but also something of the runner's embodied feelings and experience of momentum en route. Via the combination of narrative and photographs we seek a more effective way of communicating just how distance runners see and experience their training terrain. The importance of subjecting mundane everyday practices to detailed sociological analysis has been highlighted by many sociologists, including those of an ethnomethodological perspective. Indeed, without the competence of social actors in accomplishing these mundane, routine understandings and practices, it is argued, there would in fact be no social order
UWISH2 -- The UKIRT Widefield Infrared Survey for H2
We present the goals and preliminary results of an unbiased, near-infrared,
narrow-band imaging survey of the First Galactic Quadrant (10deg<l<65deg ;
-1.3deg<b<+1.3deg). This area includes most of the Giant Molecular Clouds and
massive star forming regions in the northern hemisphere. The survey is centred
on the 1-0S(1) ro-vibrational line of H2, a proven tracer of hot, dense
molecular gas in star-forming regions, around evolved stars, and in supernova
remnants. The observations complement existing and upcoming photometric surveys
(Spitzer-GLIMPSE, UKIDSS-GPS, JCMT-JPS, AKARI, Herschel Hi-GAL, etc.), though
we probe a dynamically active component of star formation not covered by these
broad-band surveys. Our narrow-band survey is currently more than 60% complete.
The median seeing in our images is 0.73arcsec. The images have a 5sigma
detection limit of point sources of K=18mag and the surface brightness limit is
10^-19Wm^-2arcsec^-2 when averaged over our typical seeing. Jets and outflows
from both low and high mass Young Stellar Objects are revealed, as are new
Planetary Nebulae and - via a comparison with earlier K-band observations
acquired as part of the UKIDSS GPS - numerous variable stars. With their
superior spatial resolution, the UWISH2 data also have the potential to reveal
the true nature of many of the Extended Green Objects found in the GLIMPSE
survey.Comment: 14pages, 8figures, 2tables, accepted for publication by MNRAS, a
version with higher resolution figures can be found at
http://astro.kent.ac.uk/~df
The nature of G52.381-0.849 and G56.240-0.345: young stellar objects associated with extended mid-infrared emission?
We report the results of visual spectroscopy, mid-infrared (MIR) mapping and
photometry, and near-infrared photometry of two candidate symbiotic stars
(IPHAS J193108.67+164950.5 and IPHAS J193709.65+202655.7) associated with
extended MIR emission. Our analysis of the continua of these sources shows that
they are likely to represent Class I-II young stellar objects (YSOs) in which
most of the IR emission arises from circumstellar discs, and for which the
physical characteristics (stellar temperatures, radii, masses and luminosities)
are similar. The extended emission is characterized by a substantial increase
in fluxes and dimensions to longer MIR wavelengths. This is likely to arise as
a result of emission by polycyclic aromatic hydrocarbons within extended
photodissociation regimes, centred upon more compact ionized regions
responsible for much of the shorter wave emission. Such dual emission
structures are characteristic of those observed in many compact HII regions.
Finally, we note that the clouds have asymmetrical structures and wind-swept
morphologies, conceivably indicative of shock interaction with external winds.
Where this is the case, then it is possible that the YSOs are located in
regions of triggered star formation.Comment: 10 pages, 7 figures, Accepted for publication in MNRAS. 25 pages in
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