256 research outputs found
Following G-quadruplex formation by its intrinsic fluorescence
AbstractWe characterized and compared the fluorescence properties of various well-defined G-quadruplex structures. The increase of intrinsic fluorescence of G-rich DNA sequences when they form G-quadruplexes can be used to monitor the folding and unfolding of G-quadruplexes as a function of cations and temperature. The temperature-dependent fluorescence spectra of different G-quadruplexes also exhibit characteristic patterns. Thus, the stability and possibly also the structure of G-quadruplexes can be characterized and distinguished by their intrinsic fluorescence spectra
Solid-state Li-ion batteries operating at room temperature using new borohydride argyrodite electrolytes
Using a new class of (BH4)- substituted argyrodite Li6PS5Z0.83(BH4)0.17, (Z =
Cl, I) solid electrolyte, Li-metal solid-state batteries operating at room
temperature have been developed. The cells were made by combining the modified
argyrodite with an In-Li anode and two types of cathode: an oxide, LixMO2 (M =
1/3Ni, 1/3Mn, 1/3Co; so called NMC) and a titanium disulfide, TiS2. The
performance of the cells was evaluated through galvanostatic cycling and
Alternating Current AC electrochemical impedance measurements. Reversible
capacities were observed for both cathodes for at least tens of cycles.
However, the high-voltage oxide cathode cell shows lower reversible capacity
and larger fading upon cycling than the sulfide one. The AC impedance
measurements revealed an increasing interfacial resistance at the cathode side
for the oxide cathode inducing the capacity fading. This resistance was
attributed to the intrinsic poor conductivity of NMC and interfacial reactions
between the oxide material and the argyrodite electrolyte. On the contrary, the
low interfacial resistance of the TiS2 cell during cycling evidences a better
chemical compatibility between this active material and substituted
argyrodites, allowing full cycling of the cathode material, 240 mAhg-1, for at
least 35 cycles with a coulombic efficiency above 97%
Polarized superfluidity in the attractive Hubbard model with population imbalance
We study a two-component Fermi system with attractive interactions and
different populations of the two species in a cubic lattice. For an
intermediate coupling we find a uniformly polarized superfluid which is stable
down to very low temperatures. The momentum distribution of this phase closely
resembles that of the Sarma phase, characterized by two Fermi surfaces. This
phase is shown to be stabilized by a potential energy gain, as in a BCS
superfluid, in contrast to the unpolarized BEC which is stabilized by kinetic
energy. We present general arguments suggesting that preformed pairs in the
unpolarized superfluid favor the stabilization of a polarized superfluid phase.Comment: 4+ pages, 4 figures, new versio
Refractive elastic scattering of carbon and oxygen nuclei: The mean field analysis and Airy structures
The experimental data on the OC and OC elastic
scatterings and their optical model analysis are presented. Detailed and
complete elastic angular distributions have been measured at the Strasbourg
Vivitron accelerator at several energies covering the energy range between 5
and 10 MeV per nucleon. The elastic scattering angular distributions show the
usual diffraction pattern and also, at larger angles, refractive effects in the
form of nuclear rainbow and associated Airy structures. The optical model
analysis unambiguously shows the evolution of the refractive scattering
pattern. The observed structure, namely the Airy minima, can be consistently
described by a nucleus-nucleus potential with a deep real part and a weakly
absorptive imaginary part. The difference in absorption in the two systems is
explained by an increased imaginary (mostly surface) part of the potential in
the OC system. The relation between the obtained potentials and
those reported for the symmetrical OO and CC
systems is drawn.Comment: 10 pages, 9 figures, Phys. rev. C in pres
Study of refractive structure in the inelastic 16O+16O scattering at the incident energies of 250 to 1120 MeV
The data of inelastic 16O+16O scattering to the lowest 2+ and 3- excited
states of 16O have been measured at Elab = 250, 350, 480, 704 and 1120 MeV and
analyzed consistently in the distorted wave Born approximation (DWBA), using
the semi- microscopic optical potentials and inelastic form factors given by
the folding model, to reveal possible refractive structure of the nuclear
rainbow that was identified earlier in the elastic 16O+16O scattering channel
at the same energies. Given the known transition strengths of the 2+ and 3-
states of 16O well determined from the (e,e') data, the DWBA description of the
inelastic data over the whole angular range was possible only if the absorption
in the exit channels is significantly increased (especially, for the
16O+16O(2+) exit channel). Although the refractive pattern of the inelastic
16O+16O scattering was found to be less pronounced compared to that observed in
the elastic scattering channel, a clear remnant of the main rainbow maximum
could still be seen in the inelastic cross section at Elab = 350 - 704 MeV.Comment: 26 pages, 10 figures, Accepted for publication in Nucl. Phys.
Improving Generalization Level in UML Models Iterative Cross Generalization in Practice
International audienc
Airy-like patterns in heavy ion elastic scattering
A semiclassical analysis of an optical potential cross section is presented.
The cross section considered is characterized by the appearance of an Airy-like
pattern. This pattern is similar to that which is present in many cross
sections, which fit the recent measurements of light heavy ion elastic
scattering, and is considered as a manifestation of a rainbow phenomenon. The
semiclassical analysis shows that, in the case considered, the oscillations
arise from the interference between the contributions from two different terms
of a multi-reflection expansion of the scattering function, and, therefore,
cannot be associated with the rainbow phenomenon.Comment: 10 pages, 5 figure
4CaaSt: Comprehensive management of Cloud services through a PaaS
The 4CaaSt project aims at developing a PaaS framework that enables flexible definition, marketing, deployment and management of Cloud-based services and applications. The major innovations proposed by 4CaaSt are the blueprint and its management and lifecycle, a one stop shop for Cloud services and the management of resources in the PaaS level (including elasticity). 4CaaSt also provides a portfolio of ready to use Cloud native services and Cloud- aware immigrant technologies
Paroxetine suppresses recombinant human P2X7 responses
P2X7 receptor (P2X7) activity may link inflammation to depressive disorders. Genetic variants of human P2X7 have been linked with major depression and bipolar disorders, and the P2X7 knockout mouse has been shown to exhibit anti-depressive-like behaviour. P2X7 is an ATP-gated ion channel and is a major regulator of the pro-inflammatory cytokine interleukin 1β (IL-1β) secretion from monocytes and microglia. We hypothesised that antidepressants may elicit their mood enhancing effects in part via modulating P2X7 activity and reducing inflammatory responses. In this study, we determined whether common psychoactive drugs could affect recombinant and native human P2X7 responses in vitro. Common antidepressants demonstrated opposing effects on human P2X7-mediated responses; paroxetine inhibited while fluoxetine and clomipramine mildly potentiated ATP-induced dye uptake in HEK-293 cells stably expressing recombinant human P2X7. Paroxetine inhibited dye uptake mediated by human P2X7 in a concentration-dependent manner with an IC50 of 24 μM and significantly reduces ATP-induced inward currents. We confirmed that trifluoperazine hydrochloride suppressed human P2X7 responses (IC50 of 6.4 μM). Both paroxetine and trifluoperazine did not inhibit rodent P2X7 responses, and mutation of a known residue (F 95L) did not alter the effect of either drug, suggesting neither drug binds at this site. Finally, we demonstrate that P2X7-induced IL-1β secretion from lipopolysaccharide (LPS)-primed human CD14+ monocytes was suppressed with trifluoperazine and paroxetine
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