5,984 research outputs found

    A new intermediate mass protostar in the Cepheus A HW2 region

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    We present the discovery of the first molecular hot core associated with an intermediate mass protostar in the CepA HW2 region. The hot condensation was detected from single dish and interferometric observations of several high excitation rotational lines (from 100 to 880K above the ground state) of SO2 in the ground vibrational state and of HC3N in the vibrationally excited states v7=1 and v7=2. The kinetic temperature derived from both molecules is 160K. The high-angular resolution observations (1.25'' x 0.99'') of the SO2 J=28(7,21)-29(6,24) line (488K above the ground state) show that the hot gas is concentrated in a compact condensation with a size of 0.6''(430AU), located 0.4'' (300AU) east from the radio-jet HW2. The total SO2 column density in the hot condensation is 10E18cm-2, with a H2 column density ranging from 10E23 to 6 x 10E24cm-2. The H2 density and the SO2 fractional abundance must be larger than 10E7cm-3 and 2 x 10E-7 respectively. The most likely alternatives for the nature of the hot and very dense condensation are discussed. From the large column densities of hot gas, the detection of the HC3N vibrationally excited lines and the large SO2 abundance, we favor the interpretation of a hot core heated by an intermediate mass protostar of 10E3 Lo. This indicates that the CepA HW2 region contains a cluster of very young stars

    Cheating, incentives, and money manipulation

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    We use different incentive schemes to study truth-telling in a die-roll task when people are asked to reveal the number rolled privately. We find no significant evidence of cheating when there are no financial incentives associated with the reports, but do find evidence of such when the reports determine financial gains or losses (in different treatments). We find no evidence of loss aversion in the standard case in which subjects receive their earnings in a sealed envelope at the end of the session. When subjects manipulate the possible earnings, we find evidence of less cheating, particularly in the loss setting; in fact, there is no significant difference in behavior between the non-incentivized case and the loss setting with money manipulation. We interpret our findings in terms of the moral cost of cheating and differences in the perceived trust and beliefs in the gain and the loss frames

    Least action description of dynamic pairing correlations in the fission of Curium and Californium isotopes based on the Gogny energy density functional

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    The impact of dynamic pairing correlations and their interplay with Coulomb antipairing effects on the systematic of the spontaneous fission half-lives for the nuclei 240−250^{240-250}Cm and 240−250^{240-250}Cf is analyzed, using a hierarchy of approximations based on the parametrization D1M of the Gogny energy density functional (EDF). First, the constrained Hartree-Fock-Bogoliubov (HFB) approximation is used to compute deformed mean-field configurations, zero-point quantum corrections and collective inertias either by using the Slater approximation to Coulomb exchange and neglecting Coulomb antipairing or by fully considering the exchange and pairing channels of the Coulomb interaction. Next, the properties of the {\it{least action}} and {\it{least energy}} fission paths are compared. In the {\it{least action}} case, pairing is identified as the relevant degree of freedom in order to minimize the action entering the Wentzel-Kramers-Brillouin (WKB) approximation to the tunneling probability through the fission barrier. Irrespective of the treatment of Coulomb exchange and antipairing, it is shown that the {\it{least action}} path obtained taking into account the pairing degree of freedom leads to stronger pairing correlations that significantly reduce the spontaneous fission half-lives tSFt_{SF} improving thereby the comparison with the experiment by several orders of magnitude. It is also shown that the Coulomb antipairing effect is, to a large extent, washed out by the {\it{least action}} procedure and therefore the tSFt_{SF} values obtained by the two different treatments of the Coulomb exchange and pairing are of similar quality.Comment: 13 pages, 8 figure

    USING STUDENT MENTAL STATE AND LEARNING SENSORY MODALITIES TO IMPROVE ADAPTIVITY IN E-LEARNING

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      In this paper, we present an innovative solution to improve adaptivity in an e-learning system using Brain Computer Interface (BCI) measures (Attention/Meditation) in order to detect changes in students’ preferred perceptual modes for learning information (VARK model). Our solution is also able to report course units and learning resources that could be difficult for the students

    Bmf upregulation through the AMP-activated protein kinase pathway may protect the brain from seizure-induced cell death.

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    Prolonged seizures (status epilepticus, SE) can cause neuronal death within brain regions such as the hippocampus. This may contribute to impairments in cognitive functioning and trigger or exacerbate epilepsy. Seizure-induced neuronal death is mediated, at least in part, by apoptosis-associated signaling pathways. Indeed, mice lacking certain members of the potently proapoptotic BH3-only subfamily of Bcl-2 proteins are protected against hippocampal damage caused by status epilepticus. The recently identified BH3-only protein Bcl-2-modifying factor (Bmf) normally interacts with the cytoskeleton, but upon certain cellular stresses, such as loss of extracellular matrix adhesion or energy crisis, Bmf relocalizes to mitochondria, where it can promote Bax activation and mitochondrial dysfunction. Although Bmf has been widely reported in the hematopoietic system to exert a proapoptotic effect, no studies have been undertaken in models of neurological disorders. To examine whether Bmf is important for seizure-induced neuronal death, we studied Bmf induction after prolonged seizures induced by intra-amygdala kainic acid (KA) in mice, and examined the effect of Bmf-deficiency on seizures and damage caused by SE. Seizures triggered an early (1-8 h) transcriptional activation and accumulation of Bax in the cell death-susceptible hippocampal CA3 subfield. Bmf mRNA was biphasically upregulated beginning at 1 h after SE and returning to normal by 8 h, while again being found elevated in the hippocampus of epileptic mice. Bmf upregulation was prevented by Compound C, an inhibitor of adenosine monophosphate-activated protein kinase, indicating Bmf expression may be induced in response to bioenergetic stress. Bmf-deficient mice showed normal sensitivity to the convulsant effects of KA, but, surprisingly, displayed significantly more neuronal death in the hippocampal CA1 and CA3 subfields after SE. These are the first studies investigating Bmf in a model of neurologic injury, and suggest that Bmf may protect neurons against seizure-induced neuronal death in vivo

    Differential Immune-Reactivity and Subcellular Distribution Reveal the Multifunctional Character of Profilin in Pollen as Major Effect of Sequences Polymorphism

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    Trabajo presentado al Annual Meeting of the American Society of Agronomy and Crop Science Society and Soil Science Society of America, celebrado en Cincinnati (USA) del 21 al 24 de octubre de 2012.Profilin, one of the major allergen (Ole e 2) of olive (Olea europaea L.) pollen, are broadly distributed actin-monomer-binding proteins (ABP). They display a major regulatory role in actin cytoskeleton dynamics, driving cell morphogenesis, sexual reproduction, and translating signals into cellular responses to different environmental stresses. Plants exhibit multiple profilin isoforms w ith distinctive biochemical properties, and differentially regulated. How ever, it is still an open question w hether these profilin isoforms, generated by multiple gene sequence polymorphism, are functionally different, as well as the role of that polymorphism in pollen allergy. Particularly, in differential epitopes generation, profilin isoforms sensitization and cross-reactivity among cultivars, and even among species. In the present study, w e have used mature pollen from olive, birch, hazel, timothy-grass, and maize, in addition to olive germinating pollen and seeds, w ith the aim to analyze the immune-reactivity and subcellular localization of profilin by using polyclonal and specific isoforms antibodies against olive and maize profilins. The results show ed immune-reactivity differences betw een the five species analyzed, betw een olive cultivars, as w ell as between reproductive and vegetative profilins. Furthermore, the existence of different profilin isoforms w as revealed along pollen germination stages. A differential subcellular distribution of profilin isoforms w as found in olive pollen. They w ere localized in the nucleus, pollen aperture regions, pollen and tube w alls and pollen tip, in addition to a general cytoplasmic distribution, in comparison to controls. Data suggest that profilin family might contain numerous functionally distinctive isoforms, spatial-temporal differentially expressed and regulated during vegetative development, pollen maturation and pollen tube grow th. Furthermore, differential immune-reactivity revealed in the study might point out the involvement of common shared and specific epitopes, generated by sequence polymorphism, in differential olive pollen cultivar sensitization of allergenic patients, and cross-reaction to pollen from different species.This study was supported by the following European Regional Development Fund cofinanced grants: MCINN BFU 2004-00601/BFI, BFU 2008-00629, BFU2011-22779, CICE (Junta de Andalucía) P2010-CVI15767, P2010-AGR6274, P2011-CVI-7487, P2011-CVI-7487, and by the coordinated project Spain/Germany MEC HA2004-0094.Peer reviewe

    Real-time moving object segmentation in H.264 compressed domain based on approximate reasoning

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    AbstractThis paper presents a real-time segmentation algorithm to obtain moving objects from the H.264 compressed domain. The proposed segmentation works with very little information and is based on two features of the H.264 compressed video: motion vectors associated to the macroblocks and decision modes. The algorithm uses fuzzy logic and allows to describe position, velocity and size of the detected regions in a comprehensive way, so the proposed approach works with low level information but manages highly comprehensive linguistic concepts. The performance of the algorithm is improved using dynamic design of fuzzy sets that avoids merge and split problems. Experimental results for several traffic scenes demonstrate the real-time performance and the encouraging results in diverse situations

    Connection of Isolated Stereoclusters by Combining C-13-RCSA, RDC, and J-Based Configurational Analyses and Structural Revision of a Tetraprenyltoluquinol Chromane Meroterpenoid from Sargassum muticum

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    The seaweed Sargassum muticum, collected on the southern coast of Galicia, yielded a tetraprenyltoluquinol chromane meroditerpene compound known as 1b, whose structure is revised. The relative configuration of 1b was determined by J-based configurational methodology combined with an iJ/DP4 statistical analysis and further confirmed by measuring two anisotropic properties: carbon residual chemical shift anisotropies (13C-RCSAs) and one-bond 1H-13C residual dipolar couplings (1DCH-RDCs). The absolute configuration of 1b was deduced by ECD/OR/TD-DFT methods and established as 3R,7S,11R
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