Bullying Prevention in New York City Public Schools: School Safety Agents\u27 Perceptions of Their Roles

Research on school-based bullying gives little attention to how school-based law enforcement personnel perceive their roles while addressing alleged and real acts of bullying, and whether their roles influence their decisions to get involved in instances of bullying. Since research neglects to assess the extent to which personal and contextual factors of law enforcement personnel assigned to schools affect how they perceive themselves in this role and their degree of involvement in instances of bullying, this study addresses two questions: (1) How do New York City Police Department School Safety Agents (SSAs) in NYC public schools perceive their roles in their school’s anti-bullying efforts? (2) How do perceptions of SSAs regarding bullying affect their responses to reported incidents of bullying? Assessing the ways SSAs perceive their roles in bullying prevention is important to understanding how their views construct their positions or importance in the process. Assessing the perceptions of SSAs concerning bullying is important to understanding how their views influence their involvement or abstention in reported instances of bullying. To address the research questions, personal and contextual factors of SSAs were developed by examining literature that identifies characteristics of officers (i.e., age, race, gender, education, and experience) and their influences on how they perceive their roles and decision-making regarding taking police action. These factors were analyzed using logistic regression and path analysis to test the influence of personal, contextual, and mediating factors on SSA involvement or abstention in reported incidents of bullying. Logistic regression analyses of individual and contextual factors suggest that SSAs’ identification of bullying was a strong predictor of involvement and intervention. Path analyses supported these results, suggesting a strong, direct effect between SSA identification of bullying and degree of involvement. Results from this study suggest that ensuring that SSAs identify instances of adolescent bullying is vital to maintaining and enhancing a school’s anti-bullying efforts, and more importantly, increasing and maintaining law enforcement personnel assigned to schools’ awareness of bullying through training and strong partnerships with school officials aid prevention of school bullying

Manifold spirals, disc-halo interactions and the secular evolution in N-body models of barred galaxies

The manifold theory of barred-spiral structure provides a dynamical mechanism explaining how spiral arms beyond the ends of galactic bars can be supported by chaotic flows extending beyond the bar's co-rotation zone. We discuss its applicability to N-body simulations of secularly evolving barred galaxies. In these simulations, we observe consecutive `incidents' of spiral activity, leading to a time-varying disc morphology. Besides disc self-excitations, we provide evidence of a newly noted excitation mechanism related to the `off-centering' effect: particles ejected in elongated orbits at major incidents cause the disc center-of-mass to recoil and be set in a wobble-type orbit with respect to the halo center of mass. The time-dependent m=1 perturbation on the disc by the above mechanism correlates with the excitation of new incidents of non-axisymmetric activity beyond the bar. At every new excitation, the manifolds act as dynamical avenues attracting particles which are directed far from corotation along chaotic orbits. The fact that the manifolds evolve morphologically in time, due to varying non-axisymmetric perturbations, allows to reconcile manifolds with the presence of multiple patterns and frequencies in the disc. We find a time-oscillating pattern speed profile $\Omega_p(R)$ at distances R between the bar's corotation, at resonance with the succession of minima and maxima of the non-axisymmetric activity beyond the bar. Finally, we discuss disc thermalization, i.e., the evolution of the disc velocity dispersion profile and its connection with disc responsiveness to manifold spirals.Comment: 20 pages, 22 figures. Accepted for publication in MNRA

Charge Symmetry Breaking in 500 MeV Nucleon-Trinucleon Scattering

Elastic nucleon scattering from the 3He and 3H mirror nuclei is examined as a test of charge symmetry violation. The differential cross-sections are calculated at 500 MeV using a microsopic, momentum-space optical potential including the full coupling of two spin 1/2 particles and an exact treatment of the Coulomb force. The charge-symmetry-breaking effects investigated arise from a violation within the nuclear structure, from the p-nucleus Coulomb force, and from the mass-differences of the charge symmetric states. Measurements likely to reveal reliable information are noted.Comment: 5 page

Disorder Effect On The Anisotropic Resistivity Of Phosphorene Determined By A Tight-binding Model

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)In this work we develop a compact multiorbital tight-binding model for phosphorene that accurately describes states near the main band gap. The model parameters are adjusted using as reference the band structure obtained by a density functional theory calculation with the hybrid HSE06 functional. We use the optimized tight-binding model to study the effects of disorder on the anisotropic transport properties of phosphorene. In particular, we evaluate how the longitudinal resistivity depends on the lattice orientation for two typical disorder models: dilute scatterers with high potential fluctuation amplitudes, mimicking screened charges in the substrate, and dense scatterers with lower amplitudes, simulating weakly bounded adsorbates. We show that the intrinsic anisotropy associated to the band structure of this material, although sensitive to the type and intensity of the disorder, is robust.9416FAPESP [2015/12974-5]DOE [DE-FG02-07ER46354]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Commodity price shocks and macroeconomic dynamics

We analyse the transmission mechanism of commodity price shocks in emerging economies. Using a panel vector autoregression, we find that the shock leads to a real exchange rate appreciation, increases in output, inflation the nominal interest rate and the trade balance, and a fall in the unemployment rate. The transmission mechanism can be understood using a dynamic stochastic general equilibrium model of a small commodity-exporting open economy with nominal as well as search and matching frictions. We find that the conduct of monetary policy is key to both the variables’ dynamics as well as to the magnitude of Dutch disease effects

Support for group-based inequality among members of low-status groups as an ingroup status-enhancement strategy

We discuss the idea that competition-based motives boost low-status group members’ support for group-based hierarchy and inequality. Specifically, the more low-status group members feel motivated to compete with a relevant high-status outgroup, based on the belief that existing status positions may be reversed, the more they will defend status differentials (i.e., high social dominance orientation; SDO). Using minimal groups (N = 113), we manipulated ingroup (low vs. high) status, and primed unstable status positions to all participants. As expected, we found that SDO positively mediates the relation between ingroup identification and collective action, when ingroup’s status is perceived to be low and status positions are perceived as highly unstable. We discuss the implications of considering situational and contextual factors to better understand individuals’ support for group-based hierarchies and inequality, and the advantages of considering ideological processes in predicting collective action.info:eu-repo/semantics/publishedVersio

A first--order irreversible thermodynamic approach to a simple energy converter

Several authors have shown that dissipative thermal cycle models based on Finite-Time Thermodynamics exhibit loop-shaped curves of power output versus efficiency, such as it occurs with actual dissipative thermal engines. Within the context of First-Order Irreversible Thermodynamics (FOIT), in this work we show that for an energy converter consisting of two coupled fluxes it is also possible to find loop-shaped curves of both power output and the so-called ecological function against efficiency. In a previous work Stucki [J.W. Stucki, Eur. J. Biochem. vol. 109, 269 (1980)] used a FOIT-approach to describe the modes of thermodynamic performance of oxidative phosphorylation involved in ATP-synthesis within mithochondrias. In that work the author did not use the mentioned loop-shaped curves and he proposed that oxidative phosphorylation operates in a steady state simultaneously at minimum entropy production and maximum efficiency, by means of a conductance matching condition between extreme states of zero and infinite conductances respectively. In the present work we show that all Stucki's results about the oxidative phosphorylation energetics can be obtained without the so-called conductance matching condition. On the other hand, we also show that the minimum entropy production state implies both null power output and efficiency and therefore this state is not fulfilled by the oxidative phosphorylation performance. Our results suggest that actual efficiency values of oxidative phosphorylation performance are better described by a mode of operation consisting in the simultaneous maximization of the so-called ecological function and the efficiency.Comment: 20 pages, 7 figures, submitted to Phys. Rev.

Hard to catch : experimental evidence supports evasive mimicry

Most research on aposematism has focused on chemically defended prey, but the signalling difficulty of capture remains poorly explored. Similar to classical Batesian and Mullerian mimicry related to distastefulness, such 'evasive aposematism' may also lead to convergence in warning colours, known as evasive mimicry. A prime candidate group for evasive mimicry are Adelpha butterflies, which are agile insects and show remarkable colour pattern convergence. We tested the ability of naive blue tits to learn to avoid and generalize Adelpha wing patterns associated with the difficulty of capture and compared their response to that of birds that learned to associate the same wing patterns with distastefulness. Birds learned to avoid all wing patterns tested and generalized their aversion to other prey to some extent, but learning was faster with evasive prey compared to distasteful prey. Our results on generalization agree with longstanding observations of striking convergence in wing colour patterns among Adelpha species, since, in our experiments, perfect mimics of evasive and distasteful models were always protected during generalization and suffered the lowest attack rate. Moreover, generalization on evasive prey was broader compared to that on distasteful prey. Our results suggest that being hard to catch may deter predators at least as effectively as distastefulness. This study provides empirical evidence for evasive mimicry, a potentially widespread but poorly understood form of morphological convergence driven by predator selection.Peer reviewe

Cloud Atlas: Rotational Spectral Modulations and potential Sulfide Clouds in the Planetary-mass, Late T-type Companion Ross 458C

Measurements of photometric variability at different wavelengths provide insights into the vertical cloud structure of brown dwarfs and planetary-mass objects. In seven Hubble Space Telescope consecutive orbits, spanning $\sim$10 h of observing time}, we obtained time-resolved spectroscopy of the planetary-mass T8-dwarf Ross 458C using the near-infrared Wide Field Camera 3. We found spectrophotometric variability with a peak-to-peak signal of 2.62$\pm$0.02 % (in the 1.10-1.60~$\mu$m white light curve). Using three different methods, we estimated a rotational period of 6.75$\pm$1.58~h for the white light curve, and similar periods for narrow $J$- and $H$- band light curves. Sine wave fits to the narrow $J$- and $H$-band light curves suggest a tentative phase shift between the light curves with wavelength when we allow different periods between both light curves. If confirmed, this phase shift may be similar to the phase shift detected earlier for the T6.5 spectral type 2MASS J22282889-310262. We find that, in contrast with 2M2228, the variability of Ross~458C shows evidence for a {color trend} within the narrow $J$-band, but gray variations in the narrow $H$-band. The spectral time-resolved variability of Ross 458C might be potentially due to heterogeneous sulfide clouds in the atmosphere of the object. Our discovery extends the study of spectral modulations of condensate clouds to the coolest T dwarfs, planetary-mass companions.Comment: Accepted in ApJ