47 research outputs found
Manufacturing consensus in a diverse field of scholarly opinions: A comment on Bushman, Gollwitzer, and Cruz (2015).
We appreciate the efforts of Bushman and Cruz to provide new data describing parents’ and professionals’ opinions regarding effects of media violence. Unfortunately, we feel it is necessary to call attention to apparent errors and inaccuracies in the way those data are interpreted and represented in their article. The article overstates the extent to which there is agreement that media violence has meaningful negative societal effects and misrepresents the relevance of the study to an understanding of the effects of media violence on societal violence. In contrast, we call for a climate of research on media violence that better recognizes the diversity of findings and conclusions in an active and growing research agenda and eschews unwarranted insinuations about effects on criminal violence from research focused on aggression-related measures not assessing violent crime
A combined theoretical and experimental study of electronic structure and optical properties of β-ZnMoO4 microcrystals
In this paper, a combined theoretical and experimental study on the electronic structure
and photoluminescence (PL) properties of beta zinc molybdate ( -ZnMoO4) microcrystals
synthesized by the hydrothermal method has been employed. These crystals were
structurally characterized by means of X-ray diffraction (XRD), Rietveld refinement,
Fourier transform Raman (FT-Raman) and Fourier transform infrared (FT-IR) spectroscopies.
Their optical properties were investigated by ultraviolet-visible (UV-vis) absorption
spectroscopy and PL measurements. First-principles quantum mechanical calculations
based on the density functional theory at the B3LYP calculation level have been
carried out. XRD patterns, Rietveld refinement, FT-Raman and FT-IR spectra showed
that these crystals have a wolframite-type monoclinic structure. The Raman and IR frequencies experimental results are in reasonable agreement with theoretically calculated results. UV-vis absorption measurements shows an optical band gap value of 3.17 eV, while the calculated band structure has a value of 3.22 eV. The density of states indicate that the main orbitals involved in the electronic structure of -ZnMoO4 crystals are (O2p-valence band and Mo 4d-conduction band). Finally, PL properties of -ZnMoO4 crystals are explained by distortions effects in octahedral [ZnO6] and [MoO6] clusters and inhomogeneous electronic distribution into the lattice with the electron density map
Elliptical galaxy nuclei activity powered by infalling globular clusters
Globular cluster systems evolve, in galaxies, due to internal and external
dynamics and tidal phenomena. One of the causes of evolution, dynamical
friction, is responsible for the orbital decay of massive clusters into the
innermost galactic regions. It is found that these clusters are effective
source of matter to feed a central galactic black hole such to make it grow and
shine as an AGN.Comment: 8 pages, 2 eps figures, in press in the Proc. of the Meeting Baryons
in Cosmic Structures, Monte Porzio (Italy), oct. 20-21 2003, ASP Conf. Ser.,
eds. E. Giallongo, G. De Zotti, N. Menc
The long-term survival chances of young massive star clusters
We review the long-term survival chances of young massive star clusters
(YMCs), hallmarks of intense starburst episodes often associated with violent
galaxy interactions. We address the key question as to whether at least some of
these YMCs can be considered proto-globular clusters (GCs), in which case these
would be expected to evolve into counterparts of the ubiquitous old GCs
believed to be among the oldest galactic building blocks. In the absence of
significant external perturbations, the key factor determining a cluster's
long-term survival chances is the shape of its stellar initial mass function
(IMF). It is, however, not straightforward to assess the IMF shape in
unresolved extragalactic YMCs. We discuss in detail the promise of using
high-resolution spectroscopy to make progress towards this goal, as well as the
numerous pitfalls associated with this approach. We also discuss the latest
progress in worldwide efforts to better understand the evolution of entire
cluster systems, the disruption processes they are affected by, and whether we
can use recently gained insights to determine the nature of at least some of
the YMCs observed in extragalactic starbursts as proto-GCs. We conclude that
there is an increasing body of evidence that GC formation appears to be
continuing until today; their long-term evolution crucially depends on their
environmental conditions, however.Comment: invited refereed review article; ChJA&A, in press; 33 pages LaTeX (2
postscript figures); requires chjaa.cls style fil
Superdeformation in 91Tc
A high-spin rotational band with 11 γ-ray transitions has been observed in 91Tc. The dynamical moment of inertia as well the transition quadrupole moment of 8.1-1.4/+1.9 eb measured for this band show the characteristics of a superdeformed band. However, the shape is more elongated than in the neighbouring A = 80-90 superdeformed nuclei. Theoretical interpretations of the band within the cranked Strutinsky approach based on two different Woods-Saxon potential parameterisations are presented. Even though an unambiguous configuration assignment proved difficult, both calculations indicate a larger deformation and at least three additional high-N intruder orbitals occupied compared to the lighter SD nuclei
Patogênese e achados clínicos, hematológicos e anatomopatológicos da infecção por Rangelia vitalii em 35 cães (1985-2009)
Susceptibility to physiological concentrations of IL-1β varies in cartilage at different anatomical locations on human osteoarthritic knee joints
Framework for e-learning assessment in dental education: a global model for the future
The framework presented in this article demonstrates strategies for a global approach to e-curricula in dental education by considering a collection of outcome assessment tools. By combining the outcomes for overall assessment, a global model for a pilot project that applies e-assessment tools to virtual learning environments (VLE), including haptics, is presented. Assessment strategies from two projects, HapTEL (Haptics in Technology Enhanced Learning) and UDENTE (Universal Dental E-learning), act as case-user studies that have helped develop the proposed global framework. They incorporate additional assessment tools and include evaluations from questionnaires and stakeholders' focus groups. These measure each of the factors affecting the classical teaching/learning theory framework as defined by Entwistle in a standardized manner. A mathematical combinatorial approach is proposed to join these results together as a global assessment. With the use of haptic-based simulation learning, exercises for tooth preparation assessing enamel and dentine were compared to plastic teeth in manikins. Equivalence for student performance for haptic versus traditional preparation methods was established, thus establishing the validity of the haptic solution for performing these exercises. Further data collected from HapTEL are still being analyzed, and pilots are being conducted to validate the proposed test measures. Initial results have been encouraging, but clearly the need persists to develop additional e-assessment methods for new learning domains