Search results for "Conducta"
showing 10 items of 611 documents
Nonsense codons suppression. An acute toxicity study of three optimized TRIDs in murine model, safety and tolerability evaluation.
2022
Stop mutations cause 11% of the genetic diseases, due to the introduction of a premature termination codon (PTC) in the mRNA, followed by the production of a truncated protein. A promising therapeutic approach is the suppression therapy by Translational Readthrough Inducing Drugs (TRIDs), restoring the expression of the protein. Recently, three new TRIDs (NV848, NV914, NV930) have been proposed, and validated by several in vitro assays, for the rescue of the CFTR protein, involved in Cystic Fibrosis disease. In this work, an acute toxicological study for the three TRIDs was conducted in vivo on mice, according to the OECD No.420 guidelines. Animals were divided into groups and treated with …
Quantum size effects in solitary wires of bismuth
2007
We have performed four-probe electrical transport measurements on solitary highly crystalline wires of semimetallic bismuth with aspect ratios up to 60 at room and at cryogenic temperatures. By proper choice of the substrate material and the film deposition parameters, lithographic wires with lateral dimensions of down to one single grain, $\sim 250$ nm, were fabricated. The electrical resistance of each wire was measured against its thickness through successive reactive ion etching of the self-same wire. Quantum size effects revealed themselves as regular oscillations in the electrical resistance. Some evidence for the semimetal-to-semiconductor phase transition has been detected. The meas…
Effect of quantized conductivity on the anomalous photon emission radiated from atomic-size point contacts
2019
We observe anomalous visible to near-infrared electromagnetic radiation emitted from electrically driven atomic-size point contacts. We show that the number of photons released strongly depends on the quantized conductance steps of the contact. Counter-intuitively, the light intensity features an exponential decay dependence with the injected electrical power. We propose an analytical model for the light emission considering an out-of-equilibrium electron distribution. We treat photon emission as bremsstrahlung process resulting from hot electrons colliding with the metal boundary and a find qualitative accord with the experimental data.
Coulomb blockade in one-dimensional arrays of high-conductance tunnel junctions
2000
Properties of one-dimensional (1D) arrays of low Ohmic tunnel junctions (i.e. junctions with resistances comparable to, or less than, the quantum resistance $R_{\rm q}\equiv h/e^2\approx 25.8$ k$\Omega$) have been studied experimentally and theoretically. Our experimental data demonstrate that -- in agreement with previous results on single- and double-junction systems -- Coulomb blockade effects survive even in the strong tunneling regime and are still clearly visible for junction resistances as low as 1 k$\Omega$. We have developed a quasiclassical theory of electron transport in junction arrays in the strong tunneling regime. Good agreement between the predictions of this theory and the …
Ballistic transport through quantum point contacts of multi-orbital oxides
2020
Linear and non-linear transport properties through an atomic-size point contact based on oxides two-dimensional electron gas is examined using the tight-binding method and the $\mathbf{k\cdot p}$ approach. The ballistic transport is analyzed in contacts realized at the (001) interface between band insulators $LaAlO_3$ and $SrTiO_3$ by using the Landauer-B\"uttiker method for many sub-bands derived from three Ti 3d orbitals ($d_{yz}$, $d_{zx}$ and $d_{xy}$) in the presence of an out-of-plane magnetic field. We focus especially on the role played by the atomic spin-orbit coupling and the inversion symmetry breaking term pointing out three transport regimes: the first, at low energies, involvi…
Transport properties of quantum dots in the Wigner molecule regime
2009
The transport properties of quantum dots with up to N=7 electrons ranging from the weak to the strong interacting regime are investigated via the projected Hartree-Fock technique. As interactions increase radial order develops in the dot, with the formation of ring and centered-ring structures. Subsequently, angular correlations appear, signalling the formation of a Wigner molecule state. We show striking signatures of the emergence of Wigner molecules, detected in transport. In the linear regime, conductance is exponentially suppressed as the interaction strength grows. A further suppression is observed when centered-ring structures develop, or peculiar spin textures appear. In the nonline…
Transport in topological insulators with bulk-surface coupling: Interference corrections and conductance fluctuations
2018
Motivated by the experimental difficulty to produce topological insulators (TIs) of the ${\text{Bi}}_{2}{\text{Se}}_{3}$ family with pure surface-state conduction, we study the effect that the bulk can have on the low-temperature transport properties of gated thin TI films. In particular, we focus on interference corrections, namely weak localization (WL) or weak antilocalization (WAL), and conductance fluctuations (CFs) based on an effective low-energy Hamiltonian. Utilizing diagrammatic perturbation theory, we first analyze the bulk and the surface separately and subsequently discuss WL/WAL and CFs when a tunneling-coupling is introduced. We identify the relevant soft diffusion modes of t…
Effect of the electromagnetic environment on arrays of small normal metal tunnel junctions: Numerical and experimental investigation
2000
We present results of a set of experiments to investigate the effect of dissipative external electromagnetic environment on tunneling in linear arrays of junctions in the weak tunneling regime. The influence of this resistance decreases as the number of junctions in the chain increases and ultimately becomes negligible. Further, there is a value of external impedance, typically \~5 k$\Omega$, at which the half-width of the zero-voltage dip in the conductance curve shows a maximum. Some new analytical formulae, based on the phase-correlation theory, along with numerical results will be presented.
Thermometry by Arrays of Tunnel Junctions
1994
We show that arrays of tunnel junctions between normal metal electrodes exhibit features suitable for primary thermometry in an experimentally adjustable temperature range where thermal and charging effects compete. $I\ensuremath{-}V$ and $\frac{\mathrm{dI}}{\mathrm{dV}}$ vs $V$ have been calculated for two junctions including a universal analytic high temperature result. Experimentally the width of the conductance minimum in this regime scales with $T$ and $N$, the number of junctions, and its value (per junction) agrees with the calculated one to within 3% for large $N$. The height of this feature is inversely proportional to $T$.
One dimensional arrays and solitary tunnel junctions in the weak coulomb blockade regime: CBT thermometry
1997
In this article we review the use of the tunnel junction arrays for primary thermometry. In addition to our basic experimental and theoretical results we stress the insensitivity of this method to the fluctuating background charges, to nonidealities in the array and to magnetic field. Important new results of this article are the low temperature corrections to the half width and depth of the measured conductance dip beyond the linear approximation. We also point ou that short arrays, single tunnel junctions in particular, show interesting deviations from the universal behaviour of the long arrays.