2,093 research outputs found
Angular Correlations in Internal Pair Conversion of Aligned Heavy Nuclei
We calculate the spatial correlation of electrons and positrons emitted by
internal pair conversion of Coulomb excited nuclei in heavy ion collisions. The
alignment or polarization of the nucleus results in an anisotropic emission of
the electron-positron pairs which is closely related to the anisotropic
emission of -rays. However, the angular correlation in the case of
internal pair conversion exhibits diverse patterns. This might be relevant when
investigating atomic processes in heavy-ion collisions performed at the Coulomb
barrier.Comment: 27 pages + 6 eps figures, uses revtex.sty and epsf.sty,
tar-compressed and uuencoded with uufile
Antibodies against Lagos Bat Virus in Megachiroptera from West Africa
To investigate the presence of Lagos bat virus (LBV)âspecific antibodies in megachiroptera from West Africa, we conducted fluorescent antibody virus neutralization tests. Neutralizing antibodies were detected in Eidolon helvum (37%), Epomophorus gambianus (3%), and Epomops buettikoferi (33%, 2/6) from Ghana. These findings confirm the presence of LBV in West Africa
An Ultrahigh CO2-Loaded Silicalite-1 Zeolite: Structural Stability and Physical Properties at High Pressures and Temperatures
[EN] We report the formation of an ultrahigh CO2-loaded pure-SiO2, silicalite-1 structure at high pressure (0.7 GPa) from the interaction of empty zeolite and fluid CO, medium. The CO2-filled structure was characterized in situ by means of synchrotron powder X-ray diffraction. Rietveld refinements and Fourier recycling allowed the location of 16 guest carbon dioxide molecules per unit cell within the straight and sinusoidal channels of the porous framework to be analyzed. The complete filling of pores by CO, molecules favors structural stability under compression, avoiding pressure-induced amorphization below 20 GPa, and significantly reduces the compressibility of the system compared to that of the parental empty one. The structure of CO2-loaded silicalite-1 was also monitored at high pressures and temperatures, and its thermal expansivity was estimated.The authors thank the Spanish Ministerio de Economia y Competitividad (MINECO), the Spanish Research Agency (AEI), and the European Fund for Regional Development (FEDER) for their financial support (MAT2016-75586-C4-1-P, MAT2016-75586-C4-3-P, MAT2015-71842-P; Severo Ochoa SEV-2012-0267; and MAT2015-71070-REDC (MALTA Consolider)). D.S.-P. and J.R-F. acknowledge MINECO for a Ramon y Cajal (RyC-2014-15643) and a Juan de la Cierva (IJCI-2014-20513) contract, respectively. A.K. acknowledges the support of the University of Valencia through the Grant UV-INV-EPC17-548561. Portions of this work were performed at GeoSoilEnviroCARS (Sector 13), Advanced Photon Source (APS), and Argonne National Laboratory. GeoSoilEnviroCARS is supported by the National Science Foundation, Earth Sciences (EAR-1128799), and the Department of Energy, GeoSciences (DE-FG02-94ER14466). This research used resources from the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory (DE-AC02-06CH11357). Use of the COMPRES-GSECARS gas loading system was supported by COMPRES under NSF Cooperative Agreement EAR 11-57758. CO2 gas was also loaded at Diamond Light Source. The authors thank the synchrotron facility ALBA-CELLS for beamtime allocation at MSPD line.Marqueno, T.; Santamaria-Perez, D.; Ruiz-Fuertes, J.; Chulia-Jordan, R.; Jorda Moret, JL.; Rey Garcia, F.; Mcguire, C.... (2018). An Ultrahigh CO2-Loaded Silicalite-1 Zeolite: Structural Stability and Physical Properties at High Pressures and Temperatures. Inorganic Chemistry. 57(11):6447-6455. https://doi.org/10.1021/acs.inorgchem.8b00523S64476455571
Endemic Circulation of European Bat Lyssavirus Type 1 in Serotine Bats, Spain
To determine the presence of European bat lyssavirus type 1 in southern Spain, we studied 19 colonies of serotine bats (Eptesicus isabellinus), its main reservoir, during 1998â2003. Viral genome and antibodies were detected in healthy bats, which suggests subclinical infection. The different temporal patterns of circulation found in each colony indicate independent endemic circulation
Modelling excited states of weakly bound complexes with density functional theory
The binding within the ethene-argon and formaldehyde-methane complexes in the ground and electronically excited states is studied with equation of motion coupled cluster theory (EOM-CCSD), second-order Møller-Plesset perturbation theory (MP2) and density functional theory with dispersion corrections (DFT-D). Electronically excited states are studied within MP2 and Kohn-Sham DFT formalisms by exploiting a procedure called the maximum overlap method that allows convergence of the relevant self-consistent field equations to higher energy (or excited state) solutions. Potential energy curves computed using MP2 are in good agreement with the EOM- CCSD calculations for both the valence and Rydberg excited states studied. For the DFT-D approach, B3LYP-D3/aug-cc-pVTZ calculations are found to be in agreement with EOM-CCSD for the ground and valence excited states. However, for the Ď3s Rydberg state of ethene-argon and the n3s Rydberg state of formaldehyde-methane significant deviation is observed, and this disagreement with EOM-CCSD is present for a variety of DFT-D based approaches. Variation of the parameters within the D2 dispersion correction results in closer agreement with EOM-CCSD for the Rydberg states but demonstrates that a different parameterisation from the ground state is required for these states. This indicates that time-dependent density functional theory calculations based upon a DFT-D reference may be satisfactory for excitations to valence states, but will potentially be inaccurate for excitations to Rydberg states, or more generally states were the nature of the electron density is significantly different from the ground state
Electronic Clinical Practice Guidelines (@CPG) : a tool to improve the approach of Major Depression (MD)
Sudden Cardiac Death and Copy Number Variants: What Do We Know after 10 Years of Genetic Analysis?
Over the last ten years, analysis of copy number variants has increasingly been applied to the study of arrhythmogenic pathologies associated with sudden death, mainly due to significant advances in the field of massive genetic sequencing. Nevertheless, few published reports have focused on the prevalence of copy number variants associated with sudden cardiac death. As a result, the frequency of these genetic alterations in arrhythmogenic diseases as well as their genetic interpretation and clinical translation has not been established. This review summarizes the current available data concerning copy number variants in sudden cardiac death-related diseases
Correspondence: Strongly-driven Re + CO2 redox reaction at high-pressure and high-temperature
SantamarĂa-Perez, D.; Mcguire, C.; Makhluf, A.; Kavner, A.; Chulia-Jordan, R.; Jorda Moret, JL.; Rey Garcia, F.... (2016). Correspondence: Strongly-driven Re + CO2 redox reaction at high-pressure and high-temperature. Nature Communications. 7:1-3. doi:10.1038/ncomms13647S137Yoo, C. S. et al. Crystal structure of carbon dioxide at high pressure: âsuperhardâ polymeric carbon dioxide. Phys. Rev. Lett. 83, 5527â5530 (1999).Santoro, M. et al. Partially collapsed cristobalite structure in the non molecular phase V in CO2 . Proc. Natl Acad. Sci. 109, 5176â5179 (2012).Datchi, F., Mallick, B., Salamat, A. & Ninet, S. Structure of polymeric carbon dioxide CO2-V. Phys. Rev. Lett. 108, 125701 (2012).Santoro, M. et al. Silicon carbonate phase formed from carbon dioxide and silica under pressure. Proc. Natl Acad. Sci. 108, 7689â7692 (2011).Santoro, M. et al. Carbon enters silica forming a cristobalite-type CO2.SiO2 solid solution. Nat. Commun. 5, 3761 (2014).Corma, A., Rey, F., Rius, J., Sabater, M. J. & Valencia, S. Supramolecular self-assembled molecules as organic directing agent for synthesis of zeolites. Nature 431, 287â290 (2004).Guth, J.-L., Kessler, H. & Wey, R. in Studies in Surface Science and Catalysis Vol. 28 (eds Murakami, Y., Iijima, A. & Ward, J. W.) 121 (Kodansha-Elsevier, 1986).Santamaria-Perez, D. et al. Exploring the chemical reactivity between carbon dioxide and three transition metals (Au, Pt, and Re) at high-pressure high-temperature conditions. Inorg. Chem. 55, 10793â10799 (2016).Magneli, A. Studies on rhenium oxides. Acta Chem. Scand. 11, 28â33 (1957)
Transiting exoplanets from the CoRoT space mission VIII. CoRoT-7b: the first Super-Earth with measured radius
We report the discovery of very shallow (DF/F = 3.4 10-4), periodic dips in
the light curve of an active V = 11.7 G9V star observed by the CoRoT satellite,
which we interpret as due to the presence of a transiting companion. We
describe the 3-colour CoRoT data and complementary ground-based observations
that support the planetary nature of the companion. Methods. We use CoRoT color
information, good angular resolution ground-based photometric observations in-
and out- of transit, adaptive optics imaging, near-infrared spectroscopy and
preliminary results from Radial Velocity measurements, to test the diluted
eclipsing binary scenarios. The parameters of the host star are derived from
optical spectra, which were then combined with the CoRoT light curve to derive
parameters of the companion. We examine carefully all conceivable cases of
false positives, and all tests performed support the planetary hypothesis.
Blends with separation larger than 0.40 arcsec or triple systems are almost
excluded with a 8 10-4 risk left. We conclude that, as far as we have been
exhaustive, we have discovered a planetary companion, named CoRoT-7b, for which
we derive a period of 0.853 59 +/- 3 10-5 day and a radius of Rp = 1.68 +/-
0.09 REarth. Analysis of preliminary radial velocity data yields an upper limit
of 21 MEarth for the companion mass, supporting the finding.
CoRoT-7b is very likely the first Super-Earth with a measured radius.Comment: Accepted in Astronomy and Astrophysics; typos and language
corrections; version sent to the printer w few upgrade
European Bat Lyssavirus in Scottish Bats
Daubenton bats may roost infrequently in human dwellings, so risk for human contact is low
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