Effect of low-level radiation on the low temperature acoustic behavior of a-SiO2

We report on the mechanical behavior of an a-SiO2 84 kHz torsional oscillator operated between 100> or =T> or =1.0 mK. Below 10 mK we observed well-differentiated transient responses which we attribute to the interaction with low-level background radiation (gamma quanta and cosmic ray micro) and which can be modeled in terms of a change in the spring constant.     

Experimental verification of the Stokes-Einstein relation in liquid Fe—FeS at 5 GPa

Experiments have been performed at 5 GPa on liquid Fe-FeS in order to determine Fe and S self-diffusivity as a function of temperature. The viscosity of the sample was then obtained using the Stokes-Einstein relation. The results are in excellent agreement with previous experiments where the viscosity of a material of the same composition under similar conditions was measured directly. These results support high, near-metallic, values of diffusivity and low viscosity in liquid Fe-S up to a few hundred K above the eutectic temperature, in contrast with some previous studies. Moreover, these results fully confirm the validity of the Stokes-Einstein relation between viscosity and diffusion coefficients for Fe_0.61S_0.39.     

Imaging cytoplasmic cAMP in mouse brainstem neurons

Background  

cAMP is an ubiquitous second messenger mediating various neuronal functions, often as a consequence of increased intracellular Ca²⁺ levels. While imaging of calcium is commonly used in neuroscience applications, probing for cAMP levels has not yet been performed in living vertebrate neuronal tissue before.     

The Early History and Personal Start-Up Stories of Synchrotron Radiation Research at Cornell University

Synchrotron radiation (SR) research at Cornell University is presently carried out at the Cornell High Energy Synchrotron Source (CHESS), a National X-ray Facility on the Cornell Electron/Positron Storage Ring (CESR), a machine mainly dedicated to X-ray production and supported by the National Science Foundation (NSF). Each year, over a thousand scientists and students use a dozen X-ray stations for multidisciplinary research in physics, chemistry, biology, environmental and materials sciences, and engineering on a machine typically operating with compact undulators at 5.3 GeV and 100 to 200 mA.