781 research outputs found
Coherent States for Isospectral Hamiltonians
We show that for the strictly isospectral Hamiltonians, the corresponding
coherent states are related by a unitary transformation. As an illustration, we
discuss, the example of strictly isospectral one-dimensional harmonic
oscillator Hamiltonians and the associated coherent states.Comment: RevTeX, 9 pages, no figure
Coherent states for a generalization of the harmonic oscillator
Coherent states for a family of isospectral oscillator Hamiltonians are derived from a suitable choice of annihilation and creation operators. The Fock-Bargmann representation is also obtained
Time representation in reinforcement learning models of the basal ganglia
Reinforcement learning (RL) models have been influential in understanding many aspects of basal ganglia function, from reward prediction to action selection. Time plays an important role in these models, but there is still no theoretical consensus about what kind of time representation is used by the basal ganglia. We review several theoretical accounts and their supporting evidence. We then discuss the relationship between RL models and the timing mechanisms that have been attributed to the basal ganglia. We hypothesize that a single computational system may underlie both RL and interval timingâthe perception of duration in the range of seconds to hours. This hypothesis, which extends earlier models by incorporating a time-sensitive action selection mechanism, may have important implications for understanding disorders like Parkinson's disease in which both decision making and timing are impaired
Assessment of hydrocarbon pollution in NW Iberian Peninsula using bioaccumulation and molecular biomarkers in Mytilus galloprovincialis
Society of Environmental Toxicology and Chemistry - SETAC Europe 15th Annual Meeting, Lille, France, May 2005.Polycyclic aromatic hydrocarbons (PAHÂŽs) are ubiquitous contaminants in marine environment as a result of uncontrolled spills, river transport, surface runoff and atmospheric deposition. A significant amount of industrial activity including shipping and oil refining is located along the NW Iberian Peninsula coast. The use of exposure biomarkers holds out promise due to the incipient state of the cost-effective methodologies for diagnosis and monitoring of oil pollution. This work presents the preliminary results concerning the identification of a set of biomarkers for an early warning detection of PAH toxicity. The bivalve Mytillus galloprovincialis was selected due to its ubiquitous distribution along coastline, being used as sentinels in pollution monitoring. This species has also an important value. Four locations in the vicinity of industrial wastewater discharges along the NW Iberian coast were selected and compared with a nearby (reference) site for (i) measurements of PAH body burdens and (ii) levels of enzyme activity: catalase (CAT), superoxide-dismutase (SOD), glutathione peroxidase (GPx), gluthathione S-transferase (GST) and Na+/K+ATPase (ATPase). The results will be discussed on the basis of their potential in providing additional evidence for discriminate between well known polluted and unpolluted sites
Construction of exact solutions to eigenvalue problems by the asymptotic iteration method
We apply the asymptotic iteration method (AIM) [J. Phys. A: Math. Gen. 36,
11807 (2003)] to solve new classes of second-order homogeneous linear
differential equation. In particular, solutions are found for a general class
of eigenvalue problems which includes Schroedinger problems with Coulomb,
harmonic oscillator, or Poeschl-Teller potentials, as well as the special
eigenproblems studied recently by Bender et al [J. Phys. A: Math. Gen. 34 9835
(2001)] and generalized in the present paper to higher dimensions.Comment: 10 page
Distorted Heisenberg Algebra and Coherent States for Isospectral Oscillator Hamiltonians
The dynamical algebra associated to a family of isospectral oscillator
Hamiltonians is studied through the analysis of its representation in the basis
of energy eigenstates. It is shown that this representation becomes similar to
that of the standard Heisenberg algebra, and it is dependent of a parameter
. We name it {\it distorted Heisenberg algebra}, where is the
distortion parameter. The corresponding coherent states for an arbitrary
are derived, and some particular examples are discussed in full detail. A
prescription to produce the squeezing, by adequately selecting the initial
state of the system, is given.Comment: 21 pages, Latex, 3 figures available as hard copies upon request from
the first Autho
Introductory Chapter: Concept and Ambition of Project TREASURE
This project has received funding from the European Unionâs Horizon 2020 research and innovation programme under grant agreement No 63447
Recombinant lipid transfer protein Tri a 14: a novel heat and proteolytic resistant tool for the diagnosis of baker's asthma
BACKGROUND Baker's asthma is an important occupational allergic disease. Wheat lipid transfer protein (LTP) Tri a 14 is a major allergen associated with wheat allergy. No panel of wheat recombinant allergens for component-resolved diagnosis of baker's asthma is currently available. OBJECTIVE To evaluate the potential role of recombinant Tri a 14 as a novel tool for the diagnosis of baker's asthma, and to test the heat and proteolytic resistance of the wheat LTP allergen. METHODS A cDNA encoding Tri a 14 was isolated and sequenced, the recombinant allergen produced in Pichia pastoris and purified by chromatographic methods. Physicochemical and immunological comparison of the natural and recombinant forms of Tri a 14 was carried out by N-terminal amino acid sequencing, matrix-assisted laser desorption/ionization mass spectrometry, circular dichroism (CD) analysis, IgE immunodetection, and specific IgE determination and ELISA-inhibition assays using a pool or individual sera from 26 patients with baker's asthma. Thermal denaturation and simulated gastrointestinal digestion of both Tri a 14 forms were checked by spectroscopic and electrophoretic methods, respectively, and biological activity by basophil activation test (BAT). RESULTS Natural and recombinant Tri a 14 were similarly folded, as indicated by their nearly identical CD spectra and heat denaturation profiles. A high interclass correlation coefficient (0.882) was found between specific IgE levels to both Tri a 14 proteins in individual sera from baker's asthma patients, but a slightly lower IgE-binding potency of rTri a 14 was detected by ELISA-inhibition assays. Natural and recombinant Tri a 14 elicited positive BAT in two and one out of three patients, respectively. Heat denaturation profiles and simulated gastrointestinal digestion assays indicated that Tri a 14 displayed a high heat and digestive proteolytic resistance, comparable to those of peach Pru p 3, the model food allergen of the LTP family. CONCLUSIONS Recombinant Tri a 14 is a potential tool for baker's asthma diagnosis, based on its physicochemical and immunological similarity with its natural counterpart. Wheat Tri a 14 shows a high thermal stability and resistance to gastrointestinal digestion
Novel tools for the diagnosis of baker's asthma: wheat lipid transfer protein Tri a 14
Background: Bakerâs asthma is among the most important occupational allergic diseases. Wheat lipid transfer protein (LTP) Tri a 14 has been reported as a major allergen associated with wheat allergy. No panel of wheat recombinant allergens for component-resolved diagnosis of bakerâs asthma is currently performed. We sought to evaluate the potential role of recombinant Tri a 14 as a novel tool for the diagnosis of bakerâs asthma, and to test the heat and proteolytic resistance of this wheat LTP allergen
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