Mass Shootings and Public Support for Gun Control

The recent spate of mass public shootings in the United States raises important questions about how these tragic events might impact mass opinion and public policy. Integrating research on focusing events, contextual effects and perceived threat, this article stipulates that residing near a mass shooting should increase support for gun control by making the threat of gun violence more salient. Drawing upon multiple data sources on mass public shootings paired with large-N survey data, it demonstrates that increased proximity to a mass shooting is associated with heightened public support for stricter gun control. Importantly, the results show that this effect does not vary by partisanship, but does vary as a function of salience-related event factors, such as repetition, magnitude and recency. Critically, the core result is replicated using panel data. Together, these results suggest a process of context-driven policy feedback between existing gun laws, egregious gun violence and demand for policy change

Foreign language exposure, cultural threat, and opposition to immigration

In the present article, we extend the notion of cultural threat posed by immigrants beyond its current conceptualization as symbolic, collective-level threats to American culture and identity. Instead, we argue that routine encounters with non-English-speaking immigrants cause many individuals to feel threatened because of real barriers to interpersonal communication and exchange. We draw upon survey and experimental data to demonstrate that local contact with immigrants who speak little to no English, as well as incidental exposure to the Spanish language, heighten feelings of cultural threat, which increases anti-immigrant sentiment and policy preferences

Social dominance and the cultural politics of immigration.

We argue that conflict over immigration largely concerns who bears the burden of cultural transaction costs, which we define as the costs associated with overcoming cultural barriers (e.g., language) to social exchange. Our framework suggests that the ability of native-born citizens to push cultural transaction costs onto immigrant out-groups serves as an important expression of social dominance. In two novel studies, we demonstrate that social dominance motives condition emotional responses to encountering cultural transaction costs, shape engagement in cultural accommodation behavior toward immigrants, and affect immigration attitudes and policy preferences

Why does fertilization reduce plant species diversity? Testing three competition-based hypotheses

1 Plant species diversity drops when fertilizer is added or productivity increases. To explain this, the total competition hypothesis predicts that competition above ground and below ground both become more important, leading to more competitive exclusion, whereas the light competition hypothesis predicts that a shift from below-ground to above-ground competition has a similar effect. The density hypothesis predicts that more above-ground competition leads to mortality of small individuals of all species, and thus a random loss of species from plots. 2 Fertilizer was added to old field plots to manipulate both below-ground and above-ground resources, while shadecloth was used to manipulate above-ground resources alone in tests of these hypotheses. 3 Fertilizer decreased both ramet density and species diversity, and the effect remained significant when density was added as a covariate. Density effects explained only a small part of the drop in diversity with fertilizer. 4 Shadecloth and fertilizer reduced light by the same amount, but only fertilizer reduced diversity. Light alone did not control diversity, as the light competition hypothesis would have predicted, but the combination of above-ground and below-ground competition caused competitive exclusion, consistent with the total competition hypothesis.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75695/1/j.1365-2745.2001.00662.x.pd

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02

Search for leptophobic Z ' bosons decaying into four-lepton final states in proton-proton collisions at root s=8 TeV

Peer reviewe

Search for high-mass diphoton resonances in proton-proton collisions at 13 TeV and combination with 8 TeV search

Peer reviewe

Search for heavy resonances decaying into a vector boson and a Higgs boson in final states with charged leptons, neutrinos, and b quarks

Peer reviewe

Measurements of differential production cross sections for a Z boson in association with jets in pp collisions at root s=8 TeV

Peer reviewe