Framing Autism Causes and Prevelance: A Content Analysis of Television Evening News Coverage--1994 Through April 2010

Autism has been declared an urgent public health concern by the U.S. government and an epidemic by some advocacy groups. Determining autism’s diagnostic criteria, prevalence, and causes have been challenging. It is important to examine how the U.S. media have contributed to the public’s understanding of autism. Previous research found that British media coverage of the theory that vaccines cause autism was shown to contribute to the decline of vaccination rates in Britain (Lewis & Speers, 2003). This study examined U.S. television news media coverage using an agenda-setting theory and media framing perspective. A content analysis was conducted of national television evening news broadcasts airing on ABC, CBS, and NBC from 1994, when autism was first recognized as a spectrum disorder through April 2010, the time of this study. Specifically, this study examined the saliency of autism stories and how autism was framed in terms of prevalence and causes

Letter from S. W. Colson to B. R. Colson

Letter from S. W. Colson to B. R. Colson. The three-page handwritten note is dated 8 February 1910. There is a transcript of the correspondence in the item PDF

Letter from S. W. Colson to B. R. Colson

Letter from S. W. Colson to B. R. Colson. The three-page handwritten note is dated 21 August 1907. There is a transcript of the correspondence in the item PDF

Letter from S. W. Colson to J. O. Barnes

Letter from S. W. Colson to J. O. Barnes. The one-page handwritten note is dated 24 May 1909. There is a transcript of the correspondence in the item PDF

Role of pair-breaking and phase fluctuations in c-axis tunneling in underdoped Bi2_{2}Sr2_{2}CaCu2_{2}O8+δ_{8+\delta}

The Josephson Plasma Resonance is used to study the c-axis supercurrent in the superconducting state of underdoped Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ with varying degrees of controlled point-like disorder, introduced by high-energy electron irradiation. As disorder is increased, the Josephson Plasma frequency decreases proportionally to the critical temperature. The temperature dependence of the plasma frequency does not depend on the irradiation dose, and is in quantitative agreement with a model for quantum fluctuations of the superconducting phase in the CuO$_{2}$ layers.Comment: 2 pages, submitted to the Proceedings of M2S-HTSC VIII Dresde

Hole and Electron Contributions to the Transport Properties of Ba(Fe_(1-x)Ru_x)_2As_2 Single Crystals

We report a systematic study of structural and transport properties in single crystals of Ba(Fe_(1-x)Ru_x)_2As_2 for x ranging from 0 to 0.5. The isovalent substitution of Fe by Ru leads to an increase of the a parameter and a decrease of the c parameter, resulting in a strong increase of the AsFeAs angle and a decrease of the As height above the Fe planes. Upon Ru substitution, the magnetic order is progressively suppressed and superconductivity emerges for x > 0.15, with an optimal Tc ~ 20K at x = 0.35 and coexistence of magnetism and superconductivity between these two Ru contents. Moreover, the Hall coefficient RH which is always negative and decreases with temperature in BaFe2As2, is found to increase here with decreasing T and even change sign for x > 0.15. For x_Ru = 0.35, photo-emission studies have shown that the number of holes and electrons are similar with n_e = n_h ~ 0.11, that is twice larger than found in BaFe2As2 [1]. Using this estimate, we find that the transport properties of Ba(Fe_0.65Ru_0.35)_2As_2 can be accounted for by the conventional multiband description for a compensated semi-metal. In particular, our results show that the mobility of holes is strongly enhanced upon Ru addition and overcomes that of electrons at low temperature when x_Ru > 0.15.Comment: new version with minor correction

Fel Oscillators with Tapered Undulators: Inclusion of Harmonic Generation and Pulse Propagation

We review the theory of FEL oscillators operating with tapered undulators. We consider the case of a uniform tapering and introduce a parameter which characterizes the effect of the tapering on the gain and on the saturation intensity. We analyze the effect of the tapering on the FEL dynamics by including the pulse propagation effects too. We analyze the importance of tapering as a tool to model the optical pulse shapes and to control the higher harmonic intensities

Supercooling of the high field vortex phase in single crystalline BSCCO

Time resolved magneto-optical images show hysteresis associated with the transition at the so-called ``second magnetization peak'' at B_sp in single-crystalline Bi_2Sr_2CaCu_2O_8+d. By rapid quenching of the high-field phase, it can be made to persist metastably in the sample down to fields that are nearly half B_sp.Comment: 2 pages, 2 figures Submitted to the conference proceedings of M2S-VI, February 200, Housto

Unconventional high-energy-state contribution to the Cooper pairing in under-doped copper-oxide superconductor HgBa2_2Ca2_2Cu3_3O8+δ_{8+\delta}

We study the temperature-dependent electronic B1g Raman response of a slightly under-doped single crystal HgBa$_2$Ca$_2$Cu$_3$O$_{8+\delta}$ with a superconducting critical temperature Tc=122 K. Our main finding is that the superconducting pair-breaking peak is associated with a dip on its higher-energy side, disappearing together at Tc. This result hints at an unconventional pairing mechanism, whereas spectral weight lost in the dip is transferred to the pair-breaking peak at lower energies. This conclusion is supported by cellular dynamical mean-field theory on the Hubbard model, which is able to reproduce all the main features of the B1g Raman response and explain the peak-dip behavior in terms of a nontrivial relationship between the superconducting and the pseudo gaps.Comment: 7 pages 4 figure

Spin Dynamics in Cuprates: Optical Conductivity of HgBa2CuO4

The electron-boson spectral density function I^2ChiOmega responsible for carrier scattering of the high temperature superconductor HgBa2CuO4 (Tc = 90 K) is calculated from new data on the optical scattering rate. A maximum entropy technique is used. Published data on HgBa2Ca2Cu3O8 (Tc = 130 K) are also inverted and these new results are put in the context of other known cases. All spectra (with two notable exceptions) show a peak at an energy (Omega_r) proportional to the superconducting transition temperature Omega_r ~= 6.3 kB.Tc. This charge channel relationship follows closely the magnetic resonance seen by polarized neutron scattering, Omega_r^{neutron} ~= 5.4 kB.Tc. The amplitudes of both peaks decrease strongly with increasing temperature. In some cases, the peak at Omega_r is weak and the spectrum can have additional maxima and a background extending up to several hundred meV