Search results for " polar"
showing 10 items of 1091 documents
State of the Art in Organic and Molecular Spintronics
2015
Organic spintronics field was born in 2002 with the pioneer work presented by the group of C. Taliani and A. V. Dediu. While molecules are easily tailored by chemical synthesis compared to inorganic materials, organics were initially seen as the ultimate media for spintronics devices due to their expected very long spin lifetime. Only very recently it was also unveiled that radically new spintronics functionalities, unavailable with conventional inorganic materials, could stem from the interface between ferromagnetic (FM) and molecular materials, giving rise to the so-called “spinterface” field. This chapter will present a general state of the art in organic and molecular spintronics fields…
A glimpse of gluons through deeply virtual compton scattering on the proton
2017
The internal structure of nucleons (protons and neutrons) remains one of the greatest outstanding problems in modern nuclear physics. By scattering high-energy electrons off a proton we are able to resolve its fundamental constituents and probe their momenta and positions. Here we investigate the dynamics of quarks and gluons inside nucleons using deeply virtual Compton scattering (DVCS)—a highly virtual photon scatters off the proton, which subsequently radiates a photon. DVCS interferes with the Bethe-Heitler (BH) process, where the photon is emitted by the electron rather than the proton. We report herein the full determination of the BH-DVCS interference by exploiting the distinct energ…
Usher syndrome: molecular links of pathogenesis, proteins and pathways.
2006
Contains fulltext : 50437.pdf (Publisher’s version ) (Closed access) Usher syndrome is the most common form of deaf-blindness. The syndrome is both clinically and genetically heterogeneous, and to date, eight causative genes have been identified. The proteins encoded by these genes are part of a dynamic protein complex that is present in hair cells of the inner ear and in photoreceptor cells of the retina. The localization of the Usher proteins and the phenotype in animal models indicate that the Usher protein complex is essential in the morphogenesis of the stereocilia bundle in hair cells and in the calycal processes of photoreceptor cells. In addition, the Usher proteins are important in…
Planar Cell Polarity Signaling in Collective Cell Movements During Morphogenesis and Disease
2012
Collective and directed cell movements are crucial for diverse developmental processes in the animal kingdom, but they are also involved in wound repair and disease. During these processes groups of cells are oriented within the tissue plane, which is referred to as planar cell polarity (PCP). This requires a tight regulation that is in part conducted by the PCP pathway. Although this pathway was initially characterized in flies, subsequent studies in vertebrates revealed a set of conserved core factors but also effector molecules and signal modulators, which build the fundamental PCP machinery. The PCP pathway in Drosophila regulates several developmental processes involving collective cel…
La Fuerza Multilateral y la multiplicidad nuclear en la OTAN (1960-1965)
2017
Desde finales de la década de 1950 y hasta 1965, el gobierno de Estados Unidos (EEUU) promovió la creación de una fuerza naval armada con misiles balísticos, conocida como Fuerza Multilateral (Multilateral Force, MLF), con tripulaciones multinacionales y bajo mando de la Organización del Tratado del Atlántico Norte (OTAN). La propuesta inicial de la administración Eisenhower trataba de satisfacer las quejas de algunos miembros de la OTAN acerca del monopolio que EEUU ejercía sobre la defensa nuclear de Europa. Aunque oficialmente se buscaba proporcionar un papel activo a los países europeos, en particular Alemania, en la estrategia nuclear conjunta, con la MLF los EEUU confiaban en inducir …
The enhanced X-ray Timing and Polarimetry mission—eXTP
2019
In this paper we present the enhanced X-ray Timing and Polarimetry mission - eXTP. eXTP is a space science mission designed to study fundamental physics under extreme conditions of density, gravity and magnetism. The mission aims at determining the equation of state of matter at supra-nuclear density, measuring effects of QED, and understanding the dynamics of matter in strong-field gravity. In addition to investigating fundamental physics, eXTP will be a very powerful observatory for astrophysics that will provide observations of unprecedented quality on a variety of galactic and extragalactic objects. In particular, its wide field monitoring capabilities will be highly instrumental to det…
Nonlinear Hanle effect in Cs vapor under strong laser excitation
2002
We report results of a theoretical and experimental study of the ground state nonlinear Hanle effect under strong laser excitation. It is shown that besides the well-known zero-magnetic field suppression of absorption on F g = F→F e = F - 1 transitions caused by population trapping, an optical pumping induced enhanced absorption occurs on F g = F→F e = F + 1 transitions for small B-fields. The latter effect becomes more pronounced for high F values. The experiment with atomic vapor of Cs (D2 line, F g = 4) confirms an increase of the spectrally unresolved fluorescence yield at zero magnetic field and 600 mW/cm2 laser intensity by 9% or 42%, when excitation occurs with linearly or circularly…
Spin Hanle effect in mesoscopic superconductors
2014
Under the terms of the Creative Commons Attribution License 3.0 (CC-BY).
Alignement moléculaire : caractérisation et application à la mesure de thermalisation ultra-rapide et au contrôle de génération d'harmoniques
2013
The thematic of this thesis is molecular alignment. The latter is a very important topic that opens the way toward a much more thin control of many phenomenons. So, we have developed a new measurement technique of the molecular alignment along one axis that permits to preserve the sign of alignment. This one is, like other measurement techniques developed by the team,based on the measurement of the refractive index variation induced by the molecular alignment.The technique developed then also permits the molecular alignment measurement, being also an application of it because it allows the third harmonic generation. In the last study, molecular alignment is implemented to show that it bring…
Signatures of photon and axion-like particle mixing in the gamma-ray burst jet
2011
Photons couple to Axion-Like Particles (ALPs) or more generally to any pseudo Nambu-Goldstone boson in the presence of an external electromagnetic field. Mixing between photons and ALPs in the strong magnetic field of a Gamma-Ray Burst (GRB) jet during the prompt emission phase can leave observable imprints on the gamma-ray polarization and spectrum. Mixing in the intergalactic medium is not expected to modify these signatures for ALP mass > 10^(-14) eV and/or for < nG magnetic field. We show that the depletion of photons due to conversion to ALPs changes the linear degree of polarization from the values predicted by the synchrotron model of gamma ray emission. We also show that when …