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Developmental Upregulation of an Alternative Form of pcp2 with Reduced GDI Activity
The pcp2/L7 gene is characterized by its very cell type-specific expression restricted to cerebellar Purkinje cells and retinal bipolar neurons. Although remarkable progress as to the biochemical properties of the encoded protein has been made, knowledge on its physiological functions remains sparse. While characterizing a pcp2-driven transgenic strain, we observed the presence of a longer, so far unknown, pcp2 transcript. Different from another recently discovered splice variant, ret-pcp2, expression of this novel transcript is observed in bipolar as well as cerebellar Purkinje cells of mid-postnatal mice. The protein encoded by our novel variant appears to be less efficient in binding to Gα subunits compared to the original L7/pcp2 protein and it is also less inhibitory with respect to GTPγ binding. Its expression in the eye appears to be independent from eye opening in postnatal mice
Interaction Among Gustation, Olfaction, and Vision in Flavor Identification
Even though the senses of taste, smell, and sight are distinct, there is a significant overlap among them in our perceptions of objects that helps us understand and differentiate the world. Everyone has experienced, when his or her nose gets congested, that his or her sense of taste changes as well. Many individuals do not equally understand the top-down processing with taste when someone sees objects they are about to eat. In the replicated study by our principle investigator, a random convenience sample of young adults (n=162) were recruited and tested to determine if they could taste four Jelly Belly flavors with one of the three different conditions: taste alone, taste with smell, or taste with smell and sight. The study revealed significant differences between the number of sensory systems used and the accuracy of flavor detection. However, no significant differences in results were observed between genders and/or for smokers versus non-smokers
Design considerations for table-top, laser-based VUV and X-ray free electron lasers
A recent breakthrough in laser-plasma accelerators, based upon ultrashort
high-intensity lasers, demonstrated the generation of quasi-monoenergetic
GeV-electrons. With future Petawatt lasers ultra-high beam currents of ~100 kA
in ~10 fs can be expected, allowing for drastic reduction in the undulator
length of free-electron-lasers (FELs). We present a discussion of the key
aspects of a table-top FEL design, including energy loss and chirps induced by
space-charge and wakefields. These effects become important for an optimized
table-top FEL operation. A first proof-of-principle VUV case is considered as
well as a table-top X-ray-FEL which may open a brilliant light source also for
new ways in clinical diagnostics.Comment: 6 pages, 4 figures; accepted for publication in Appl. Phys.
Precision Measurement of the First Ionization Potential of Nobelium
One of the most important atomic properties governing an element’s chemical behavior is the energy required to remove its least-bound electron, referred to as the first ionization potential. For the heaviest elements, this fundamental quantity is strongly influenced by relativistic effects which lead to unique chemical properties. Laser spectroscopy on an atom-at-a-time scale was developed and applied to probe the optical spectrum of neutral nobelium near the ionization threshold. The first ionization potential of nobelium is determined here with a very high precision from the convergence of measured Rydberg series to be 6.626 21 ± 0.000 05 eV . This work provides a stringent benchmark for state-of-the-art many-body atomic modeling that considers relativistic and quantum electrodynamic effects and paves the way for high-precision measurements of atomic properties of elements only available from heavy-ion accelerator facilities
Developments for resonance ionization laser spectroscopy of the heaviest elements at SHIP
The experimental determination of atomic levels and the first ionization potential of the heaviest elements (Z >= 100) is key to challenge theoretical predictions and to reveal changes in the atomic shell structure. These elements are only artificially produced in complete-fusion evaporation reactions at on-line facilities such as the GSI in Darmstadt at a rate of, at most, a few atoms per second. Hence, highly sensitive spectroscopic methods are required. Laser spectroscopy is one of the most powerful and valuable tools to investigate atomic properties. In combination with a buffer-gas filled stopping cell, the Radiation Detected Resonance Ionization Spectroscopy (RADRIS) technique provides the highest sensitivity for laser spectroscopy on the heaviest elements. The RADRIS setup, as well as the measurement procedure, have been optimized and characterized using the a-emitter 155Yb in on-line conditions, resulting
in an overall efficiency well above 1%. This paves the way for a successful search of excited atomic levels in nobelium and heavier elements.publisher: Elsevier
articletitle: Developments for resonance ionization laser spectroscopy of the heaviest elements at SHIP
journaltitle: Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
articlelink: http://dx.doi.org/10.1016/j.nimb.2016.06.001
content_type: article
copyright: © 2016 Elsevier B.V. All rights reserved.status: publishe
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