Z' Bosons at Colliders: a Bayesian Viewpoint

We revisit the CDF data on di-muon production to impose constraints on a large class of Z' bosons occurring in a variety of E_6 GUT based models. We analyze the dependence of these limits on various factors contributing to the production cross-section, showing that currently systematic and theoretical uncertainties play a relatively minor role. Driven by this observation, we emphasize the use of the Bayesian statistical method, which allows us to straightforwardly (i) vary the gauge coupling strength, g', of the underlying U(1)'; (ii) include interference effects with the Z' amplitude (which are especially important for large g'); (iii) smoothly vary the U(1)' charges; (iv) combine these data with the electroweak precision constraints as well as with other observables obtained from colliders such as LEP 2 and the LHC; and (v) find preferred regions in parameter space once an excess is seen. We adopt this method as a complementary approach for a couple of sample models and find limits on the Z' mass, generally differing by only a few percent from the corresponding CDF ones when we follow their approach. Another general result is that the interference effects are quite relevant if one aims at discriminating between models. Finally, the Bayesian approach frees us of any ad hoc assumptions about the number of events needed to constitute a signal or exclusion limit for various actual and hypothetical reference energies and luminosities at the Tevatron and the LHC.Comment: PDFLaTeX, 24 pages, 7 figures. Version with improved tables and figure

Capturing and testing perceptual-cognitive expertise: A comparison of stationary and movement response methods

Numerous methods have been used to study expertise and performance. In the present article, we compare the cognitive thought processes of skilled soccer players when responding to film-based simulations of defensive situations involving two different experimental conditions. Participants either remained stationary in a seated position (n = 10) or were allowed to move (n = 10) in response to life-size film sequences of 11 versus 11 open-play soccer situations viewed from a player’s perspective. Response accuracy and retrospective verbal reports of thinking were collected across the two task conditions. In the movement-based response group, participants generated a greater number of verbal report statements, including a higher proportion of evaluation, prediction, and action planning statements, than did participants in the stationary group. Findings suggest that the processing strategies employed during performance differ depending on the nature of the response required of participants. Implications for behavioral methods and experimental design are discussed

SF-36 includes less Parkinson Disease (PD)-targeted content but is more responsive to change than two PD-targeted health-related quality of life measures

To compare validity including responsiveness, and internal consistency reliability and scaling assumptions of a generic (SF-36) and Parkinson Disease (PD)-targeted (PDQ-39; PDQUALIF) health-related quality of life (HRQOL) measures. Ninety-six PD patients were administered for all HRQOL measures by telephonic interview at baseline and 18 months. Relative efficiency and responsiveness were compared relative to four external criteria (self-ratings of PD’s daily effects, global Quality of Life, PD symptom severity, and a depression screener). We examined whether PD-targeted measures explained unique variance beyond the SF-36 by regressing criterion variables on HRQOL scales/items. Adequacy of PD-targeted measures’ original scaling was explored by item-scale correlations. Relative efficiency estimates were similar for generic and PD-targeted measures across all criteria. Responsiveness analyses showed that the SF-36 yielded large (>0.8) effect sizes (ES) for three of eight scales for each of two criterion variables, compared to only one large ES for any scale in either PD-targeted measure. Adjusted R 2 increased from 14 to 27% in regression models that included PD-targeted items compared to models with only SF-36 scales. Item-scale correlations showed significant cross-loading of items across scales of the PD-targeted measures. SF-36 responsiveness was better than that of two PD-targeted measures, yet those measures had content that significantly explains PD patients’ HRQOL

Multi-dimensionality and variability in folk classification of stingless bees (Apidae: Meliponini)

Background: Not long ago Eugene Hunn suggested using a combination of cognitive, linguistic, ecological and evolutionary theories in order to account for the dynamic character of ethnoecology in the study of folk classification systems. In this way he intended to question certain homogeneity in folk classifications models and deepen in the analysis and interpretation of variability in folk classifications. This paper studies how a rural culturally mixed population of the Atlantic Forest of Misiones (Argentina) classified honey-producing stingless bees according to the linguistic, cognitive and ecological dimensions of folk classification. We also analyze the socio-ecological meaning of binomialization in naming and the meaning of general local variability in the appointment of stingless bees. Methods: We used three different approaches: the classical approach developed by Brent Berlin which relies heavily on linguistic criteria, the approach developed by Eleonor Rosch which relies on psychological (cognitive) principles of categorization and finally we have captured the ecological dimension of folk classification in local narratives. For the second approximation, we developed ways of measuring the degree of prototypicality based on a total of 107 comparisons of the type "X is similar to Y" identified in personal narratives. Results: Various logical and grouping strategies coexist and were identified as: graded of lateral linkage, hierarchical and functional. Similarity judgments among folk taxa resulted in an implicit logic of classification graded according to taxa's prototypicality. While there is a high agreement on naming stingless bees with monomial names, a considerable number of underrepresented binomial names and lack of names were observed. Two possible explanations about reported local naming variability are presented. Conclusions: We support the multidimensionality of folk classification systems. This confirms the specificity of local classification systems but also reflects the use of grouping strategies and mechanisms commonly observed in other cultural groups, such as the use of similarity judgments between more or less prototypical organisms. Also we support the idea that alternative naming results from a process of fragmentation of knowledge or incomplete transmission of knowledge. These processes lean on the facts that culturally based knowledge, on the one hand, and biologic knowledge of nature on the other, can be acquired through different learning pathways.Fil: Zamudio, Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); ArgentinaFil: Hilgert, Norma Ines. Consejo Nacional de Investigaciones Cientiâ­ficas y Tecnicas. Centro Cientifico Tecnologico Nordeste. Instituto de Biologia Subtropical. Instituto de Biologia Subtropical - Nodo Puerto Iguazu; Argentin

Search for gamma-ray emission from magnetars with the Fermi Large Area Telescope

We report on the search for 0.1-10 GeV emission from magnetars in 17 months of Fermi Large Area Telescope (LAT) observations. No significant evidence for gamma-ray emission from any of the currently-known magnetars is found. The most stringent upper limits to date on their persistent emission in the Fermi-LAT energy range are estimated between ~10^{-12}-10^{-10} erg/s/cm2, depending on the source. We also searched for gamma-ray pulsations and possible outbursts, also with no significant detection. The upper limits derived support the presence of a cut-off at an energy below a few MeV in the persistent emission of magnetars. They also show the likely need for a revision of current models of outer gap emission from strongly magnetized pulsars, which, in some realizations, predict detectable GeV emission from magnetars at flux levels exceeding the upper limits identified here using the Fermi-LAT observations.Comment: ApJ Letters in press; Corresponding authors: Caliandro G. A., Hadasch D., Rea N., Burnett

Detection of Gamma-Ray Emission from the Starburst Galaxies M82 and NGC 253 with the Large Area Telescope on Fermi

We report the detection of high-energy gamma-ray emission from two starburst galaxies using data obtained with the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. Steady point-like emission above 200 MeV has been detected at significance levels of 6.8 sigma and 4.8 sigma respectively, from sources positionally coincident with locations of the starburst galaxies M82 and NGC 253. The total fluxes of the sources are consistent with gamma-ray emission originating from the interaction of cosmic rays with local interstellar gas and radiation fields and constitute evidence for a link between massive star formation and gamma-ray emission in star-forming galaxies.Comment: Submitted to ApJ Letter

Fermi Gamma-ray Imaging of a Radio Galaxy

The Fermi Gamma-ray Space Telescope has detected the gamma-ray glow emanating from the giant radio lobes of the radio galaxy Centaurus A. The resolved gamma-ray image shows the lobes clearly separated from the central active source. In contrast to all other active galaxies detected so far in high-energy gamma-rays, the lobe flux constitutes a considerable portion (>1/2) of the total source emission. The gamma-ray emission from the lobes is interpreted as inverse Compton scattered relic radiation from the cosmic microwave background (CMB), with additional contribution at higher energies from the infrared-to-optical extragalactic background light (EBL). These measurements provide gamma-ray constraints on the magnetic field and particle energy content in radio galaxy lobes, and a promising method to probe the cosmic relic photon fields.Comment: 27 pages, includes Supplementary Online Material; corresponding authors: C.C. Cheung, Y. Fukazawa, J. Knodlseder, L. Stawar

Inheritance of fertility in broiler chickens

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Fermi Large Area Telescope observations of PSR J1836+5925

The discovery of the gamma-ray pulsar PSR J1836+5925, powering the formerly unidentified EGRET source 3EG J1835+5918, was one of the early accomplishments of the Fermi Large Area Telescope (LAT). Sitting 25 degrees off the Galactic plane, PSR J1836+5925 is a 173 ms pulsar with a characteristic age of 1.8 million years, a spindown luminosity of 1.1$\times10^{34}$ erg s$^{-1}$, and a large off-peak emission component, making it quite unusual among the known gamma-ray pulsar population. We present an analysis of one year of LAT data, including an updated timing solution, detailed spectral results and a long-term light curve showing no indication of variability. No evidence for a surrounding pulsar wind nebula is seen and the spectral characteristics of the off-peak emission indicate it is likely magnetospheric. Analysis of recent XMM observations of the X-ray counterpart yields a detailed characterization of its spectrum, which, like Geminga, is consistent with that of a neutron star showing evidence for both magnetospheric and thermal emission.Comment: Accepted to Astrophysical Journa