Influence of retardation effects on 2D magnetoplasmon spectrum

Within dissipationless limit the magnetic field dependence of magnetoplasmon spectrum for unbounded 2DEG system found to intersect the cyclotron resonance line, and, then approaches the frequency given by light dispersion relation. Recent experiments done for macroscopic disc-shape 2DEG systems confirm theory expectations.Comment: 2 pages,2 figure

Home Computer User Security Behavioral Intention: A Replication Study from Guam

This replication study is a methodological replication of Study 1 of Anderson and Agarwal (2010) (A&A) using data collected from Guam to investigate information security (InfoSec) behavioral intention. This study also extended the A&A Model by examining the effect of gender on each construct of the model. Our findings are very similar to those reported by A&A, and indicate that the model is generalizable to the population on Guam. We also observed the effect of gender on several constructs of the model. As this study cannot confirm whether the slight differences between the result of A&A and this study are related to cultural differences, we suggest future replication studies be conducted to examine how culture would affect our security behavior intention. We also suggest practitioners consider gender as an important factor when designing mechanisms to encourage people to practice information security behavior

3-[(8-But­oxy­quinolin-2-yl)meth­yl]-1-(pyridin-2-ylmeth­yl)-1H-imidazol-3-ium hexa­fluoridophosphate

In the cation of the title compound, C23H25N4O+·PF6 −, the imidazolium ring make dihedral angles of 87.20 (6) and 79.89 (5)° with the pyridine ring and the quinoline system, respectively. In the crystal, C—H⋯F and C—H⋯N hydrogen bonds are observed

Comparing Social Science and Computer Science Workflow Processes for Studying Group Interactions

In this article, a team of authors from the Geeks and Groupies workshop, in Leiden, the Netherlands, compare prototypical approaches to studying group interaction in social science and computer science disciplines, which we call workflows. To help social and computer science scholars understand and manage these differences, we organize workflow into three major stages: research design, data collection, and analysis. For each stage, we offer a brief overview on how scholars from each discipline work. We then compare those approaches and identify potential synergies and challenges. We conclude our article by discussing potential directions for more integrated and mutually beneficial collaboration that go beyond the producer–consumer model

The cluster abundance in cosmic string models for structure formation

We use the present observed number density of large X-ray clusters to constrain the amplitude of matter density perturbations induced by cosmic strings on the scale of $8 h^{-1}$Mpc ($\sigma_8$), in both open cosmologies and flat models with a non-zero cosmological constant. We find a slightly lower value of $\sigma_8$ than that obtained in the context of primordial Gaussian fluctuations generated during inflation. This lower normalization of $\sigma_8$ results from the mild non-Gaussianity on cluster scales, where the one point probability distribution function is well approximated by a $\chi^2$ distribution. We use our estimate of $\sigma_8$ to constrain the string linear energy density $\mu$ and show that it is consistent with the COBE normalization.Comment: 5 pages, 2 figure

Gravitational anomalies signaling the breakdown of classical gravity

Recent observations for three types of astrophysical systems severely challenge the GR plus dark matter scenario, showing a phenomenology which is what modified gravity theories predict. Stellar kinematics in the outskirts of globular clusters show the appearance of MOND type dynamics on crossing the $a_{0}$ threshold. Analysis shows a ``Tully-Fisher'' relation in these systems, a scaling of dispersion velocities with the fourth root of their masses. Secondly, an anomaly has been found at the unexpected scales of wide binaries in the solar neighbourhood. Binary orbital velocities cease to fall along Keplerian expectations, and settle at a constant value, exactly on crossing the $a_{0}$ threshold. Finally, the inferred infall velocity of the bullet cluster is inconsistent with the standard cosmological scenario, where much smaller limit encounter velocities appear. This stems from the escape velocity limit present in standard gravity; the ``bullet'' should not hit the ``target'' at more than the escape velocity of the joint system, as it very clearly did. These results are consistent with extended gravity, but would require rather contrived explanations under GR, each. Thus, observations now put us in a situation where modifications to gravity at low acceleration scales cease to be a matter of choice, to now become inevitable.Comment: 10 pages, 5 figures, Astrophysics and Space Science Proceedings 38, 4