Browsing Facultad de Ciencias Exactas by Issue Date
Now showing items 1-20 of 482
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Conserved Charges for Gravity with Locally Anti–de Sitter Asymptotics
(American Physical Society, 2000-02)A new formula for the conserved charges in 3+1 gravity for spacetimes with local anti-de Sitter asymptotic geometry is proposed. It is shown that requiring the action to have an extremum for this class of asymptotia sets ... -
Conserved charges for even dimensional asymptotically AdS gravity theories
(American Physical Society, 2000-08)Mass and other conserved Noether charges are discussed for solutions of gravity theories with locally anti-de Sitter (AdS) asymptotics in 2n dimensions. The action is supplemented with a boundary term whose purpose is to ... -
Environmental reprogramming of the expression of protein kinase CK2β subunit in fish
(Springer, 2001)The dramatic segregation of the nucleolar components in winter-acclimatized carp is the most striking cellular-phenotypical feature observed during the seasonal adaptation of this fish toward the circannual changes in its ... -
Isolation and characterization of homokaryotic strains from the ligninolytic basidiomycete Ceriporiopsis subvermispora
(Federation of European Microbiological Societies, 2001-05)Genetic analyses of the lignin-degrading fungus Ceriporiopsis subvermispora is complicated by a dikaryotic nuclear condition and the absence of spore forms. Previous investigations had identified a family of closely related ... -
In vitro biocontrol activity of Trichoderma harzianum on Alternaria alternata in the presence of growth regulators
(Electronic Journal of Biotechnology, 2001-08)The in vitro biocontrol ability of Trichoderma harzianum on the phytopathogen Alternaria alternata improved in the presence of the growth regulators gibberellic acid (GA3), or indolacetic acid (IAA) or benzylaminopurine ... -
Supersymmetry of gravitational ground states
(Institute of Physics Publishing, 2002-05)A class of black objects which are solutions of pure gravity with negative cosmological constant are classified through the mapping between the Killing spinors of the ground state and those of the transverse section. It ... -
A complementary view to the bonding pattern in the N5 +cation an electron localization function and local temperature analysis
(Sociedad Chilena de Química, 2003)The electron localization function (ELF), a local measure of the Pauli repulsion effect, and the local Kohn-Sham temperature analysis, which is defined within the framework of a local thermodynamics description of density ... -
The horizon and its charges in the first order gravity
(Institute of Physics Publishing, 2003-04)In this work the algebra of charges of diffeomorphisms at the horizon of generic black holes is analyzed within first order gravity. This algebra reproduces the algebra of diffeomorphisms at the horizon, (Diff (S 1)), ... -
Spin-orbit effects metal-metal-multiple bonded m2x2 halide complexes
(Sociedad Chilena de Química, 2004)Dirac molecular spinor calculations on the Re2Cl82-, Re2Br82-, Os2Cl82- (both staggered and eclipsed isomers), Os2Br82- and Os2I82- cluster ions are reported. Here we report the calculations of the spin-orbit splitting ... -
About the difference in the quadrupole splitting of water between cationic and anionic nematic lyotropic liquid crystals. H-2-NMR and molecular dynamics study
(SOCIEDAD CHILENA DE QUIMICA, 2004)Deuterium quadrupole splittings, of deuterated water, Deltav, in anionic discotic nematic lyomesophases are always much larger than in cationic mesophases. To explore the possible origins of this difference, Deltav and T-1 ... -
Quantitative representation of reactivity, selectivity and site activation concepts in organic chemistry
(Sociedad Chilena de Química, 2004)Reactivity, selectivity and site activation are classical concepts in chemistry which are amenable to quantitative representation, in terms of static global, local and non local density response functions. The use of ... -
On the reduction of 4-oxo-4h-benzopyran-3-carbaldehydes : global and local electrophilicity patterns
(Sociedad Chilena de Química, 2004)The theoretical global and local electrophilicity patterns of substituted and chelated 4-oxo-4H-benzopyran-3-carbaldehydes (formylchromones) have been evaluated using the electrophilicity index proposed by Parr et al [J. ... -
Local reactivity index as descriptor of benzene adsorption in cluster models of exchanged zeolite-Y
(Elsevier, 2004-01)The adsorption of benzene over sites I, II and III of Cu- and Na-exchanged zeolite-Y, has been studied using the energy profiles for the host-guess interaction, and electronic descriptors of reactivity such as the electronic ... -
A Lux-like quorum sensing system in the extreme acidophile Acidithiobacillus ferrooxidans
(BMC, 2005)The genome of the acidophilic, proteobacterium Acidithiobacillus ferrooxidans, contains linked but divergently oriented genes, termed afeI and afeR, whose predicted protein products are significantly similar to the LuxI ... -
D = 4 pure spinor superstring and N = 2 strings
(Scuola Internazionale Superiore di Studi Avanzati (SISSA) [Associate Organisation] Springer Verlag [Commercial Publisher], 2005-10)We study the compactification of the pure spinor superstring down to four dimensions. We find that the compactified string is described by a conformal invariant system for both the four dimensional and for the compact six ... -
On the use of the whole eigenvalue spectrum to obtain single molecule band structures and solid band gaps for molecular electronics studies
(Sociedad Chilena de Química, 2006)A Density Functional microscopic model of C60, consisting of seven molecular orbitals (3 occupied and 4 empty), was employed to get the best values for the half-width and the scanning distance of the mathematical function ... -
The limits of the extended hückel theory to calculate the total density of states of medium-sized molecules
(Sociedad Chilena de Química, 2006)Two medium-sized molecular systems X60 (X=C,N) were analyzed using Extended Hückel, Density Functional and ab initio Hartree-Fock methods. The aim of the work was to test the reliability of the EHT methodology to calculate ... -
Synthesis and conformational analysis of leptocarpin derivatives. Influence of modification of the oxirane ringon leptocarpin's cytotoxic activity.
(2014 Sociedad Chilena de Química, 2006)ABSTRACT The reaction in acidconditions of Leptocarpin 1, a compound with antitumor activity, formed two new isomeric products, 8b-angeloyl-1b,3b-dihydroxy-4,10-dimethyl,-D11(13) methylen-4Z,9Z-dieneheliangol-6,12-olide ... -
Three-dimensional origin of Gödel spacetimes and black holes
(American Physical Society, 2006-02)We construct Gödel-type black hole and particle solutions to Einstein-Maxwell theory in 2+1 dimensions with a negative cosmological constant and a Chern-Simons term. On-shell, the electromagnetic stress-energy tensor ... -
Hardness and softness kernels, and related indices in the spin polarized version of density functional theory
(Elsevier, 2006-02)In this Letter, the mathematical expressions corresponding to the kernel, local and global spin softness have been derived, and their relationship with other indices have been explored. Introducing various spin kernels, ...
