Search results for "NELLI"
showing 10 items of 368 documents
Molecular and functional analysis of the (6-4) photolyase from the hexactinellid Aphrocallistes vastus.
2003
The hexactinellid sponges (phylum Porifera) represent the phylogenetically oldest metazoans that evolved 570-750 million years ago. At this period exposure to ultraviolet (UV) light exceeded that of today and it may be assumed that this old taxon has developed a specific protection system against UV-caused DNA damage. A cDNA was isolated from the hexactinellid Aphrocallistes vastus which comprises high sequence similarity to genes encoding the protostomian and deuterostomian (6-4) photolyases. Subsequently functional studies were performed. It could be shown that the sponge gene, after transfection into mutated Escherichia coli, causes resistance of the bacteria against UV light. Recombinan…
Phylogenetic Position of the Hexactinellida Within the Phylum Porifera Based on the Amino Acid Sequence of the Protein Kinase C from Rhabdocalyptus d…
1998
Recent analyses of genes encoding proteins typical for multicellularity, especially adhesion molecules and receptors, favor the conclusion that all metazoan phyla, including the phylum Porifera (sponges), are of monophyletic origin. However, none of these data includes cDNA encoding a protein from the sponge class Hexactinellida. We have now isolated and characterized the cDNA encoding a protein kinase C, belonging to the C subfamily (cPKC), from the hexactinellid sponge Rhabdocalyptus dawsoni. The two conserved regions, the regulatory part with the pseudosubstrate site, the two zinc fingers, and the C2 domain, as well as the catalytic domain were used for phylogenetic analyses. Sequence al…
Quantum-state transfer via resonant tunneling through local-field-induced barriers
2013
Efficient quantum-state transfer is achieved in a uniformly coupled spin-1/2 chain, with open boundaries, by application of local magnetic fields on the second and last-but-one spins, respectively. These effective barriers induce the appearance of two eigenstates, bilocalized at the edges of the chain, which allow a high-quality transfer also at relatively long distances. The same mechanism may be used to send an entire e-bit (e.g., an entangled qubit pair) from one to the other end of the chain. DOI: 10.1103/PhysRevA.87.042313
Perpendicular transport properties of YBa_2Cu_3O_{7-\delta}/PrBa_2Cu_3O_{7-\delta} superlattices
2000
The coupling between the superconducting planes of YBa2Cu3O{7-\delta}/ PrBa2Cu3O{7-\delta} superlattices has been measured by c-axis transport. We show that only by changing the thickness of the superconducting YBa2Cu3O{7-\delta} layers, it is possible to switch between quasi-particle and Josephson tunneling. From our data we deduce a low temperature c-axis coherence length of 0.27 nm.
Evolution of a Non-Hermitian Quantum Single-Molecule Junction at Constant Temperature
2021
This work concerns the theoretical description of the quantum dynamics of molecular junctions with thermal fluctuations and probability losses. To this end, we propose a theory for describing non-Hermitian quantum systems embedded in constant-temperature environments. Along the lines discussed in [A. Sergi et al., Symmetry 10 518 (2018)], we adopt the operator-valued Wigner formulation of quantum mechanics (wherein the density matrix depends on the points of the Wigner phase space associated to the system) and derive a non-linear equation of motion. Moreover, we introduce a model for a non-Hermitian quantum single-molecule junction (nHQSMJ). In this model the leads are mapped to a tunneling…
The Instability of the NbTe2 Surface Structure
2002
Low energy electron diffraction from clean NbTe 2 surfaces shows very diffuse reflections. The effect is attributed to an anisotropic heating of the irradiated Te-Nb-Te surface layer. Diffraction patterns for electron energies below 90 eV correspond to an overlapped contribution from numerous domains, belonging to three orientational variants. Electrons of higher energies stabilize the parent high-temperature CdI 2 structure. A similar effect is observed during scanning tunneling microscopy, where the expected surface corrugation is usually lost for tunneling currents of a few ten nA.
Incorporating spatial structure and stochasticity in endangered Bonelli’s eagle’s population models: implications for conservation and management
2008
Population models have played a chief role informing management decisions for the endangered Bonelli’s eagle (Aquila fasciata) in Spain. In this paper, we incorporate spatial structure and stochasticity in the construction of individual-based metapopulation models, and use these models to explore the effects of possible management actions on the persistence of the species in Spain. To build the models we used data on seven sub-populations that have experienced different trends in the last decades, and we introduced new estimates of pre-adult survival rate. The elasticity analysis of our models showed that when the interchange of individuals among sub-populations is taken into account, pre-a…
Natal dispersal and recruitment of two Bonelli's Eagles <I>Aquila fasciata</I>: a four-year satellite tracking study
2009
To study natal dispersal and recruitment to the breeding population in Bonelli's Eagle, two nestlings were tagged with satellite transmitters in the Iberian Peninsula in 2002. Their monthly ranges and distances were computed and fitted to regression models to describe their general trend. One bird, a female, dispersed and settled rapidly in an area which she explored intensively during four years and which finally became her first breeding site. The natal dis- persal distance was 441 km, and the bird cannot therefore be considered philopatric. The other bird, a male, alternated between long travelling episodes and settlement in particular areas, exploring different regions both distant from…
Carbonyl Back-Bonding Influencing the Rate of Quantum Tunnelling in a Dysprosium Metallocene Single-Molecule Magnet.
2019
The isocarbonyl-ligated metallocene coordination polymers [Cp*2M(μ-OC)W(Cp)(CO)(μ-CO)]∞ were synthesized with M = Gd (1, L = THF) and Dy (2, no L). In a zero direct-current field, the dysprosium version 2 was found to be a single-molecule magnet (SMM), with analysis of the dynamic magnetic susceptibility data revealing that the axial metallocene coordination environment leads to a large anisotropy barrier of 557(18) cm–1 and a fast quantum-tunnelling rate of ∼3.7 ms. Theoretical analysis of two truncated versions of 2, [Cp*2Dy{(μ-OC)W(Cp)(CO)2}2]− (2a), and [Cp*2Dy(OC)2]+ (2b), in which the effects of electron correlation outside the 4f orbital space were studied, revealed that tungsten-to-…
Magnetic Tunnel Junction (MTJ) Sensors for Integrated Circuits (IC) Electric Current Measurement
2013
We report on MgO Magnetic Tunnel Junction (MTJ) devices focusing on their potential application in the measurement of electrical current at the integrated circuit level. Single devices and full bridges have been specifically developed for this purpose. A sort of different designs regarding their geometry arrangement as well as the number of constitutive elements have been tested. Experimental characterization has been performed and results including impedance and sensitivity measurements are given.