Low Voltage I-V Characteristics in Magnetic Tunnel Junctions

We show that elastic currents that take into account variations of the tunnel transmitivity with voltage and a large ratio of majority to minority spin densities of states of the $s$ band, can account for the low voltage current anomalies observed in magnet-oxide-magnet junctions. The anomalies can be positive, negative or have a mixed form, depending of the position of the Fermi level in the $s$ band, in agreement with observations. Magnon contribution is negligible small to account for the sharp drop of the magnetoresistance with the voltage bias.Comment: 8 pages, 3 postscript figure

Estudio de una lucerna romana inédita hallada en Burriana (Castellón)

La lucerna fue hallada en el año 2007 en una excavación de urgencia realizada en el yacimiento arqueológico del Marjalet, situado en el municipio de Burriana, en la costa de la provincia de Castellón. Esta lucerna se enmarca en la tipología Loeschcke IC de gran importancia comercial durante la época Neroniana-Flavia. Se trata de una lucerna de volutas en cuya parte central muestra una escena decorativa con la imagen del ser mitológico Pegaso y en su base de forma incisa presenta la inscripción P.

Real time speech translator

This document is written to report on my work on the Real Time Voice Translator Project, the project I carried out as my final thesis project during the academic year 2007‐2008. During this period I have been working in the Research and Development Center (RDC) for Mobile Applications, a department of the Czech Technical University (CTU) in Prague. In the RDC I was a member of the Automatic Call Center Project (ACC Project) team, and within it, I was assigned to carry out the Real Time Voice Translator Project. The Automatic Call Center Project (ACC Project), now renamed to Voice2Web Project, is a project carried out by the Research and Development Center. The RDC is a department inside the Electro Technical Faculty of the CTU that carries out Research and Development projects regrding the Information Technologies (IT). Some of its partners are IBM, Vodafone and Ericson, who the RDC is doing projects for.  The ACC Project began on 2007 and its aim is to develop Voice Applications, within the IBM and RDC agreement, using IBM Voice Technologies and whatever open standards or open source software. IBM is an ACC Project partner and provides financing for it. It also provides hardware and software licenses to the ACC Project and gives us support. The members of the ACC Project are developing several Voice Applications at the same time, all them following the ACC Project purposes.   Although this document is focused on the Real Time Voice Translator Project, it will also explain in the introduction some aspects of the ACC Project. This is because the Real Time Voice Translator Project has a lot of points in common with it and it is worth, to understand it well, understand some points of the ACC Project as well. 

Multi-View & Multi-Vendor Ventricular Segmentation

Cardiac MRI segmentation is a clinically interesting field that can accelerate and improve diagnostics. Targeting the capability of models towards better generalizing in unseen subsets of data that can better represent minority cohorts, greatly enhancing the lives of multiple people, cheapening the diagnostics, and making current models more resilient to unseen pathologies. In this project, our aim was to study how different architectures behave in a multiview multivendor multipathology scenario with respect to these generalization capacities and explore how postprocessing can improve the results. In addition, we also assess the computational cost that these models need to ensure that they are valid for clinical products and machines that can be reached at any clinical center

Collapse of the Gd3+Gd^{3+} ESR fine structure throughout the coherent temperature of the Gd-doped Kondo Semiconductor CeFe4P12CeFe_{4}P_{12}

Experiments on the $Gd^{3+}$ Electron Spin Resonance (ESR) in the filled skutterudite $Ce_{1-x}Gd_{x}Fe_{4}P_{12}$ ($x \approx 0.001$), at temperatures where the host resistivity manifests a smooth insulator-metal crossover, provides evidence of the underlying Kondo physics associated with this system. At low temperatures (below $T \approx K$), $Ce_{1-x}Gd_{x}Fe_{4}P_{12}$ behaves as a Kondo-insulator with a relatively large hybridization gap, and the $Gd^{3+}$ ESR spectra displays a fine structure with lorentzian line shape, typical of insulating media. The electronic gap is attributed to the large hybridization present in the coherent regime of a Kondo lattice, when Ce 4f-electrons cooperate with band properties at half-filling. Mean-field calculations suggest that the electron-phonon interaction is fundamental at explaining the strong 4f-electron hybridization in this filled skutterudite. The resulting electronic structure is strongly temperature dependent, and at about $T^{*} \approx 160 K$ the system undergoes an insulator-to-metal transition induced by the withdrawal of 4f-electrons from the Fermi volume, the system becoming metallic and non-magnetic. The $Gd^{3+}$ ESR fine structure coalesces into a single dysonian resonance, as in metals. Still, our simulations suggest that exchange-narrowing via the usual Korringa mechanism, alone, is not capable of describing the thermal behavior of the ESR spectra in the entire temperature region ($4.2$ - $300$ K). We propose that temperature activated fluctuating-valence of the Ce ions is the missing ingredient that, added to the usual exchange-narrowing mechanism, fully describes this unique temperature dependence of the $Gd^{3+}$ ESR fine structure observed in $Ce_{1-x}Gd_{x}Fe_{4}P_{12}$.Comment: 19 pages, 6 figure

Stars and brown dwarfs in the sigma Orionis cluster. III. OSIRIS/GTC low-resolution spectroscopy of variable sources

Context. Although many studies have been performed so far, there are still dozens of low-mass stars and brown dwarfs in the young sigma Orionis open cluster without detailed spectroscopic characterisation. Aims. We look for unknown strong accretors and disc hosts that were undetected in previous surveys. Methods. We collected low-resolution spectroscopy (R ~ 700) of ten low-mass stars and brown dwarfs in sigma Orionis with OSIRIS at the Gran Telescopio Canarias under very poor weather conditions. These objects display variability in the optical, infrared, Halpha, and/or X-rays on time scales of hours to years. We complemented our spectra with optical and near-/mid-infrared photometry. Results. For seven targets, we detected lithium in absorption, identified Halpha, the calcium doublet, and forbidden lines in emission, and/or determined spectral types for the first time. We characterise in detail a faint, T Tauri-like brown dwarf with an 18 h-period variability in the optical and a large Halpha equivalent width of -125+/-15 AA, as well as two M1-type, X-ray-flaring, low-mass stars, one with a warm disc and forbidden emission lines, the other with a previously unknown cold disc with a large inner hole. Conclusions. New unrevealed strong accretors and disc hosts, even below the substellar limit, await discovery among the list of known sigma Orionis stars and brown dwarfs that are variable in the optical and have no detailed spectroscopic characterisation yet.Comment: A&A, in press (accepted for publication in section 14. Catalogs and data of Astronomy and Astrophysics

POTENTIAL GAINS FROM COOPERATION FOR VESSELS AND COUNTRIES

In this paper, we consider a model in which fishing boats or firms share the stock of fish in a fishing ground. The catches made by each firm reduce the stock available for the rest of the firms, which directly affects their profits. We aim to quantify in a static framework the gain in welfare obtained by the firms if they decide to cooperate in order to attain an individually rational efficient outcome. One of the main results is that, both the incentives for the firms to cooperate and the minimum level of catches which permits any gain in welfare decrease as real wage increases. On the other hand, the greater the asymmetry among boats of firms, the more difficult it will be to reach any cooperative agreement.Resource /Energy Economics and Policy,

Evaluation of RAGE (receptor for advanced glycation end products) in dogs with chronic enteropathy

Ziel dieser Studie ist die Bestimmung der Serum-sRAGE-Kon- zentrationen bei Hunden mit Chronische Enteropathie (CIE) und deren Zusammenhang mit histologischen sowie klinisch- pathologischen Befunden. Ein weiteres Ziel der Studie ist der quantitative Vergleich der Expression von Transmembran (full-length)-RAGE entlang des Gastrointestinaltrakts bei Hunden mit CIE sowie die Untersuchung auf deren Zusammenhang mit Serum-sRAGE-Konzentrationen sowie klinischen, klinisch-pathologischen und histologischen Befunden. Die Ergebnisse deuten auf eine Dysregulation der RAGE/sRAGE-Achse bei der CIE des Hundes und legen nahe, dass die RAGE-Signalwege eine Rolle bei der Patho- genese dieser Erkrankung spielen.:Introduction. Review of Literature Functional Anatomy and Physiology of the Intestines. Anatomy of the Intestines. Gastrointestinal Physiology Small Intestinal Physiology. Large Intestinal Physiology. Gastrointestinal Neuronal and Endocrine System Gastrointestinal Immune System Innate Immunity and Acquired Immunity Intestinal Microbiome Enteropathies in Dogs.Definition Acute Enteropathy Chronic Enteropathies Food-Responsive Enteropathy (FRE) Antibiotic-Responsive Enteropathy (ARE) Steroid- or Immunosuppressant-responsive enteropathy (SRE/IRE) Non-Responsive Enteropathy (NRE) Protein-Losing Enteropathy (PLE) Diagnostic evaluation of dogs with suspected CIE Clinical and Clinicopathologic Approach Diagnostic Imaging of the Abdomen Laboratory Tests for Gastrointestinal Disease Serum cobalamin (vitamin B12 Serum folic acid (vitamin B9) Serum C-reactive protein (CRP) Fecal calprotectin and S100A12 Protein Fecal alpha1-proteinase inhibitor (α1PI) Gastrointestinal Histopathology attern Recognition Receptors Receptor for Advanced Glycation End Products Aims and Hypotheses Own Publications Association between serum soluble receptor for advanced glycation end-products (RAGE) deficiency and severity of clinicopathologic evidence of canine chronic in- flammatory enterophy Dysregulation of gastrointestinal RAGE (receptor for advanced glycation end products) expression in dogs with chronic inflammatory enteropathy Discussion Objective of the Study Discussion of the results Limitations of the Study Conclusions Summary Zusammenfassung References Acknowledgment

Effects of pyruvate administration on infarct volume and neurological deficits following permanent focal cerebral ischemia in rats

Recent experimental evidences indicate that pyruvate, the final metabolite of glycolysis, has a remarkable protective effect against different types of brain injury. The purpose of this study was to assess the neuroprotective effect and the neurological outcome after pyruvate administration in a model of ischemic stroke induced by permanent middle cerebral artery occlusion (pMCAO) in rats. Three doses of pyruvate (250, 500 and 1000 mg/kg, i.p.) or vehicle were administered intraperitoneally 30 min after pMCAO. In other set of experiments, pyruvate was given either before, immediately after ischemia or in a long-term administration paradigm. Functional outcome, mortality and infarct volume were determined 24 h after stroke. Even when the lowest doses of pyruvate reduced mortality and neurological deficits, no concomitant reduction in infarct volume was observed. The highest dose of pyruvate increased cortical infarction by 27% when administered 30 min after pMCAO. In addition, when pyruvate was given before pMCAO, a significant increase in neurological deficits was noticed. Surprisingly, on the contrary of what was found in the case of transient global ischemia, present findings do not support a great neuroprotective role for pyruvate in permanent focal cerebral ischemia, suggesting two distinct mechanisms involved in the effects of this glycolytic metabolite in the ischemic brain