28 research outputs found
Aspectos fundamentales de la suspensión de pagos
La presente tesis está compuesta por ocho capítulos enfocados en dar una visión doctrinaria y jurídica de la institución de la suspensión de pagos, para lo cual y en cuanto al aspecto doctrinario se hizo acopio de varios tratadistas, en donde la bibliografía más precisa y abundante es de autores españoles y mexicanos, mientras que para él aspectos jurídico se utilizó la siguiente legislación salvadoreña: el Código de Comercio, la Ley de Procedimientos Mercantiles en cuanto a su tramitación procesal, así como también el Código de Procedimientos Civiles
Generalized Rashba Electron-Phonon Coupling and Superconductivity in Strontium Titanate
SrTiO3 is known for its proximity to a ferroelectric phase and for showing an
'optimal' doping for superconductivity with a characteristic dome-like
behaviour resembling systems close to a quantum critical point. Several
mechanisms have been proposed to link these phenomena, but the abundance of
undetermined parameters prevents a definite assessment. Here, we use ab initio
computations supplemented with a microscopic model to study the linear coupling
between conduction electrons and the ferroelectric soft transverse modes
allowed in the presence of spin-orbit coupling. We find a robust Rashba-like
coupling, which can become surprisingly strong for particular forms of the
polar eigenvector. We characterize this sensitivity for general eigenvectors
and, for the particular form deduced by hyper-Raman scattering experiments, we
find a BCS pairing coupling constant of the right order of magnitude to support
superconductivity. The ab initio computations enable us to go beyond the
linear-in-momentum conventional Rashba-like interaction and naturally explain
the dome behaviour including a characteristic asymmetry. The dome is attributed
to a momentum dependent quenching of the angular momentum due to a competition
between spin-orbit and hopping energies. The optimum density for having maximum
Tc results in rather good agreement with experiments without free parameters.
These results make the generalized Rashba dynamic coupling to the ferroelectric
soft mode a compelling pairing mechanism to understand bulk superconductivity
in doped SrTiO3.Comment: 18 pages, 8 figure
Genome-based trait prediction in multi- environment breeding trials in groundnut
Genomic selection (GS) can be an efficient and cost-effective breeding approach which captures both small- and
large-effect genetic factors and therefore promises to achieve higher genetic gains for complex traits such as yield and oil content in groundnut. A training population was constituted with 340 elite lines followed by genotyping with 58 K ‘Axiom_Arachis’ SNP array and phenotyping for key agronomic traits at three locations in India. Four GS models were tested using three different random cross-validation schemes (CV0, CV1 and CV2). These models are: (1) model 1 (M1 = E + L) which includes the main effects of environment (E) and line (L); (2) model 2 (M2 = E + L + G) which includes the main effects of markers (G) in addition to E and L; (3) model 3 (M3 = E + L + G + GE), a naïve interaction model; and (4) model 4 (E + L + G + LE + GE), a naïve and informed interaction model. Prediction accuracy estimated for four models indicated clear advantage of the inclusion of marker information which was reflected in better prediction accuracy achieved with models M2, M3 and M4 as compared to M1 model. High prediction accuracies (> 0.600) were observed for days to 50% flowering, days to maturity, hundred seed weight, oleic acid, rust@90 days, rust@105 days and late leaf spot@90 days, while
medium prediction accuracies (0.400–0.600) were obtained for pods/plant, shelling %, and total yield/plant. Assessment of comparative prediction accuracy for different GS models to perform selection for untested genotypes, and unobserved and unevaluated environments provided greater insights on potential application of GS breeding in groundnut
Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality