Search results for " DOM"
showing 10 items of 2750 documents
Assessing the Beneficial Effects of Economic Growth: The Harmonic Growth Index
2011
In this paper we introduce the multidimensional notion of harmonic growth as a situation of diffused well-being associated to an increase of per capita GDP. We say that a country experienced a harmonic growth if during the observed period all the key indicators, proxies of the endogenous and exogenous forces driving population well-being, show a significantly common pattern with the income dynamics. The notion is operationalized via an index of time series harmony which follows the functional data analysis approach. This Harmonic Growth Index (HGI) is based on comparisons between the coefficients from cubic B-splines interpolation. Such indices are then synthesized in order to provide the g…
Origin of the Metazoan Immune System: Identification of the Molecules and Their Functions in Sponges
2011
SYNOPSIS. During the evolutionary transition to Metazoa, cell-cell- as well as cell-matrix recognition molecules have been formed, which made a further step in evolution possible, the establishment of an immune system. Sponges [Porifera] represent the oldest still extant metazoan phylum and consequently testify to major features of the common metazoan ancestor, the Urmetazoa. Most studies with respect to evolution and phylogeny in sponges have been performed with the marine demosponges Suberites domuncula and Geodia cydonium. These animals possess effective defense systems against microbes and parasites which involve engulfment of bacteria into specific cells, but also signal transduction p…
On the computational aspects of a symmetric multidomain BEM for elastoplastic analysis
2012
The symmetric boundary element method (SBEM) is applied to the elasto-plastic analysis of bodies subdivided into substructures. This methodology is based on the use of: a multidomain SBEMapproach, for the evaluation of the elastic predictor; a return mapping algorithm based on the extremal paths theory, for the evaluation of inelastic quantities characterizing the plastic behaviour of each substructure; and a transformation of the domain inelastic integrals of each substructure into corresponding boundary integrals. The elastic analysis is performed by using the SBEM displacement approach, which has the advantage of creating system equations that only consist of nodal kinematical unknowns a…
Causal and Non-Causal Frequency Domain Assessment of Spontaneous Baroreflex Sensitivity after Myocardial Infarction
2020
Acute myocardial infarction (AMI) is thought to alter the baroreflex control of arterial pressure. We tested this hypothesis investigating the changes of the cardiovascular response after AMI in comparison with young and old healthy controls studied at rest and during head-up tilt, using causal and non-causal frequency domain measures of the baroreflex sensitivity. Our results indicate: (i) the importance of using a causal approach that takes into account not only feedback but also feedforward effects in the study of interactions between the heart period and the arterial pressure; (ii) the compromised capacity of baroreceptors to control SAP fluctuations in post-AMI patients, both at rest a…
Multipactor radiation analysis within a waveguide region based on a frequency-domain representation of the dynamics of charged particles
2009
[EN] A technique for the accurate computation of the electromagnetic fields radiated by a charged particle moving within a parallel-plate waveguide is presented. Based on a transformation of the time-varying current density of the particle into a time-harmonic current density, this technique allows the evaluation of the radiated electromagnetic fields both in the frequency and time domains, as well as in the near- and far-field regions. For this purpose, several accelerated versions of the parallel-plate Green's function in the frequency domain have been considered. The theory has been successfully applied to the multipactor discharge occurring within a two metal-plates region. The proposed…
Quadratic least-squares formulation for a local active noise control with stochastic domain and noise source
2012
A local active noise control method that uses stochastic numerical acoustical modeling is introduced. The frequency domain acoustical simulations are performed by a sequence solutions to Helmholtz equations approximated by FEM. The proposed ANC method maps microphone measurements linearly to the output signals of antinoise actuators. The matrix defining the linear mapping is optimized for each frequency to minimize expected value of the noise. The paper concentrates on defining the quadratic least-squares optimization problem for the minimization of the sound pressure field in the silet region. The formulation leads to a robust and accurate noise control in stochastic domains that has a sto…
L‐Aspartate as a high‐quality nitrogen source in Escherichia coli : Regulation of L‐aspartase by the nitrogen regulatory system and interaction of L‐…
2020
Escherichia coli uses the C4-dicarboxylate transporter DcuA for L-aspartate/fumarate antiport, which results in the exploitation of L-aspartate for fumarate respiration under anaerobic conditions and for nitrogen assimilation under aerobic and anaerobic conditions. L-Aspartate represents a high-quality nitrogen source for assimilation. Nitrogen assimilation from L-aspartate required DcuA, and aspartase AspA to release ammonia. Ammonia is able to provide by established pathways the complete set of intracellular precursors (ammonia, L-aspartate, L-glutamate, and L-glutamine) for synthesizing amino acids, nucleotides, and amino sugars. AspA was regulated by a central regulator of nitrogen meta…
Origin of Insulin Receptor-Like Tyrosine Kinases in Marine Sponges
1999
One autapomorphic character restricted to all Metazoa including Porifera [sponges] is the existence of transmembrane receptor tyrosine kinases (RTKs). In this study we screened for molecules from one subfamily within the superfamily of the insulin receptors. The subfamily includes the insulin receptors (InsR), the insulin-like growth factor I receptors, and the InsR-related receptors--all found in vertebrates--as well as the InsR-homolog from Drosophila melanogaster. cDNAs encoding putative InsRs were isolated from the hexactinellid sponge Aphrocallistes vastus, the demosponge Suberites domuncula, and the calcareous sponge Sycon raphanus. Phylogenetic analyses of the catalytic domains of th…
Functional and conformational properties of the exclusive C-domain from the Arabidopsis copper chaperone (CCH)
2001
The Arabidopsis thaliana copper chaperone (CCH) is a small copper binding protein involved in copper trafficking. When compared to homologues from other eukaryotes, CCH has two different domains; the conserved N-domain and the plant-exclusive C-domain, a C-terminal extension with an unusual amino-acid composition. In order to characterize this extra C-domain, the CCH protein, the N-domain and the C-domain were all expressed separately in heterologous systems. While the N-domain retained the copper chaperone and antioxidant properties described for the yeast Atx1 and human HAH1 counterparts, the C-domain displayed particular structural properties that would be necessary to optimize copper ho…
Mini-Review: Two Brothers in Crime – The Interplay of TRESK and TREK in Human Diseases
2021
Abstract TWIK-related spinal cord potassium (TRESK) and TWIK-related potassium (TREK) channels are both subfamilies of the two-pore domain potassium (K2P) channel group. Despite major structural, pharmacological, as well as biophysical differences, emerging data suggest that channels of these two subfamilies are functionally more closely related than previously assumed. Recent studies, for instance, indicate an assembling of TRESK and TREK subunits, leading to the formation of heterodimeric channels with different functional properties compared to homodimeric ones. Formation of tandems consisting of TRESK and TREK subunits might thus multiply the functional diversity of both TRESK and TREK …