Cultural Change and Threat Perception: Causal Implications on White Nationalist Beliefs and Outgroup Restricting Policies

Cultural change is an inevitable aspect of life; however, how people react to cultural change can dramatically vary. Of particular interest to this analysis is how White Americans react to cultural changes occurring in the nation. Across three studies, I examined how White Americans may see cultural change, in the form of demographic change, as threatening and how these threat perceptions may influence their endorsement of White nationalism beliefs and support for outgroup restricting policies. This investigation found that White participants who read about real demographic changes occurring in the nation endorsed more threat perceptions (Study 1). Furthermore, there was tentative evidence that certain threat perceptions were positively related to endorsement of White nationalism beliefs and support for outgroup restricting policies. Although attempts to manipulate specific threat perceptions within the cultural change paradigm was relatively successful (Study 2a), none of these threat manipulations predicted endorsement of White nationalism beliefs nor support for outgroup restricting policies (Study 2b). Theoretical implications and avenues for future research are discussed

Defining the American System

American systems are commonly discussed in system justification literature; however, little is known about what subsystems are important to Americans’ understanding of the overall American system and what impact status has on forming these perceptions. This study attempts to answer these questions by asking Americans about their perceptions of the overall American system and seven underlying subsystems (political, economic, employment, education, criminal justice, social services, and health care). Three hundred and forty three community members from the Chicagoland area and Mechanical Turk were recruited to participate in the survey. It was hypothesized that high-status participants would prioritize the subsystems that they justify while low-status participants would prioritize the subsystems they do not justify in their understanding of the overall American system. Status, measured by income, did not significantly predict this relationship. It was further hypothesized that justification of subsystems and income would each have a positive relationship with justification of the overall American system. Justification of subsystems was found to be a significant predictor of justification of the American system; however, status did not predict American system justification. Finally, an exploratory cluster analysis revealed three distinct clusters which indicated different ways participants conceptualized the American system. This analysis makes the first steps towards understanding how various subsystems within the American system are conceptualized and perceived by people of different statuses. Future directions for this research are discussed

Cultural Change and Threat Perception: Casual Implications on White Nationalist Beliefs and Outgroup Restricting Policies

Cultural change is an inevitable aspect of life; however, how people react to cultural change can dramatically vary. Of particular interest to this analysis is how White Americans react to cultural changes occurring in the nation. Across three studies, I examined how White Americans may see cultural change, in the form of demographic change, as threatening and how these threat perceptions may influence their endorsement of White nationalism beliefs and support for outgroup restricting policies. This investigation found that White participants who read about real demographic changes occurring in the nation endorsed more threat perceptions (Study 1). Furthermore, there was tentative evidence that certain threat perceptions were positively related to endorsement of White nationalism beliefs and support for outgroup restricting policies. Although attempts to manipulate specific threat perceptions within the cultural change paradigm was relatively successful (Study 2a), none of these threat manipulations predicted endorsement of White nationalism beliefs nor support for outgroup restricting policies (Study 2b). Theoretical implications and avenues for future research are discussed

The Perceived Demands of CrossFit

Rhabdomyolysis is the breakdown of muscle tissue causing myoglobin, creatine kinase, and other intracellular proteins and electrolytes to leak into circulation, disrupting cell homeostasis. Exertional rhabdomyolysis (ER) occurs after extremely rigorous physical training that could include high amounts of strenuous eccentric exercise. There has been an increase in reports for mild to severe ER as well as other musculoskeletal injuries as the popularity of extreme conditioning programs (e.g., CrossFit®) increases. Therefore, the main purposes of this investigation were to identify: primary risk factors associated with ER during CrossFit®, CrossFit® workouts that might induce a higher risk for the development of ER, and ratings of perceived exertion (RPE) for CrossFit® vs. American College of Sports Medicine (ACSM) training guidelines. A questionnaire was completed by 101 CrossFit® participants and 56 ACSM participants (n = 157). CrossFit® and ACSM groups reported significantly different RPEs of 7.29 ± 1.74 and 5.52 ± 1.35 (p ≤ 0.001), and performed significantly different hard days per week of 3.99 ± 1.07 and 3.55 ± 1.39 (p = 0.044), respectively. The top five perceived hardest workouts based on frequency were Fran (47), Murph (27), Fight Gone Bad (10), Helen (9) and Filthy 50 (9). One occurrence of ER was reported out of 101 CrossFit® participants. Therefore, the overall risk of developing ER may be minimal, especially if a participant understands their body’s limitations in regard to the intensity of CrossFit®

Bar-driven evolution and quenching of spiral galaxies in cosmological simulations

We analyse the output of the hi-res cosmological zoom-in simulation ErisBH to study self-consistently the formation of a strong stellar bar in a Milky Way-type galaxy and its effect on the galactic structure, on the central gas distribution and on star formation. The simulation includes radiative cooling, star formation, SN feedback and a central massive black hole which is undergoing gas accretion and is heating the surroundings via thermal AGN feedback. A large central region in the ErisBH disk becomes bar-unstable after z~1.4, but a clear bar-like structure starts to grow significantly only after z~0.4, possibly triggered by the interaction with a massive satellite. At z~0.1 the bar reaches its maximum radial extent of l~2.2 kpc. As the bar grows, it becomes prone to buckling instability, which we quantify based on the anisotropy of the stellar velocity dispersion. The actual buckling event is observable at z~0.1, resulting in the formation of a boxy-peanut bulge clearly discernible in the edge-on view of the galaxy at z=0. The bar in ErisBH does not dissolve during the formation of the bulge but remains strongly non-axisymmetric down to the resolution limit of ~100 pc at z=0. During its early growth, the bar exerts a strong torque on the gas within its extent and drives gas inflows that enhance the nuclear star formation on sub-kpc scales. Later on the infalling gas is nearly all consumed into stars and, to a lesser extent, accreted onto the central black hole, leaving behind a gas-depleted region within the central ~2 kpc. Observations would more likely identify a prominent, large-scale bar at the stage when the galactic central region has already been quenched. Bar-driven quenching may play an important role in disk-dominated galaxies at all redshift. [Abridged]Comment: 13 pages, 12 figures, MNRAS submitte

Black Hole Starvation and Bulge Evolution in a Milky Way-like Galaxy

We present a new zoom-in hydrodynamical simulation, "Erisbh", which follows the cosmological evolution and feedback effects of a supermassive black hole at the center of a Milky Way-type galaxy. ErisBH shares the same initial conditions, resolution, recipes of gas cooling, star formation and feedback, as the close Milky Way-analog "Eris", but it also includes prescriptions for the formation, growth and feedback of supermassive black holes. We find that the galaxy's central black hole grows mainly through mergers with other black holes coming from infalling satellite galaxies. The growth by gas accretion is minimal because very little gas reaches the sub-kiloparsec scales. The final black hole is, at z=0, about 2.6 million solar masses and it sits closely to the position of SgrA* on the MBH-MBulge and MBH-sigma planes, in a location consistent with what observed for pseudobulges. Given the limited growth due to gas accretion, we argue that the mass of the central black hole should be above 10^5 solar masses already at z~8. The effect of AGN feedback on the host galaxy is limited to the very central few hundreds of parsecs. Despite being weak, AGN feedback seems to be responsible for the limited growth of the central bulge with respect to the original Eris, which results in a significantly flatter rotation curve in the inner few kiloparsecs. Moreover, the disk of ErisBH is more prone to instabilities, as its bulge is smaller and its disk larger then Eris. As a result, the disk of ErisBH undergoes a stronger dynamical evolution relative to Eris and around z=0.3 a weak bar grows into a strong bar of a few disk scale lengths in size. The bar triggers a burst of star formation in the inner few hundred parsecs, provides a modest amount of new fuel to the central black hole, and causes the bulge of ErisBH to have, by z=0, a box/peanut morphology.(Abridged)Comment: 16 pages, 16 figures. Submitted to MNRA

Growing black holes and galaxies: black hole accretion versus star formation rate

We present a new suite of hydrodynamical simulations and use it to study, in detail, black hole and galaxy properties. The high time, spatial and mass resolution, and realistic orbits and mass ratios, down to 1:6 and 1:10, enable us to meaningfully compare star formation rate (SFR) and BH accretion rate (BHAR) timescales, temporal behaviour and relative magnitude. We find that (i) BHAR and galaxy-wide SFR are typically temporally uncorrelated, and have different variability timescales, except during the merger proper, lasting ~0.2-0.3 Gyr. BHAR and nuclear (<100 pc) SFR are better correlated, and their variability are similar. Averaging over time, the merger phase leads typically to an increase by a factor of a few in the BHAR/SFR ratio. (ii) BHAR and nuclear SFR are intrinsically proportional, but the correlation lessens if the long-term SFR is measured. (iii) Galaxies in the remnant phase are the ones most likely to be selected as systems dominated by an active galactic nucleus (AGN), because of the long time spent in this phase. (iv) The timescale over which a given diagnostic probes the SFR has a profound impact on the recovered correlations with BHAR, and on the interpretation of observational data.Comment: Accepted for publication in MNRA

Supermassive black hole pairs in clumpy galaxies at high redshift: delayed binary formation and concurrent mass growth

Massive gas-rich galaxy discs at $z \sim 1-3$ host massive star-forming clumps with typical baryonic masses in the range $10^7-10^8$~M$_{\odot}$ which can affect the orbital decay and concurrent growth of supermassive black hole (BH) pairs. Using a set of high-resolution simulations of isolated clumpy galaxies hosting a pair of unequal-mass BHs, we study the interaction between massive clumps and a BH pair at kpc scales, during the early phase of the orbital decay. We find that both the interaction with massive clumps and the heating of the cold gas layer of the disc by BH feedback tend to delay significantly the orbital decay of the secondary, which in many cases is ejected and then hovers for a whole Gyr around a separation of 1--2 kpc. In the envelope, dynamical friction is weak and there is no contribution of disc torques: these lead to the fastest decay once the orbit of the secondary BH has circularised in the disc midplane. In runs with larger eccentricities the delay is stronger, although there are some exceptions. We also show that, even in discs with very sporadic transient clump formation, a strong spiral pattern affects the decay time-scale for BHs on eccentric orbits. We conclude that, contrary to previous belief, a gas-rich background is not necessarily conducive to a fast BH decay and binary formation, which prompts more extensive investigations aimed at calibrating event-rate forecasts for ongoing and future gravitational-wave searches, such as with Pulsar Timing Arrays and the future evolved Laser Interferometer Space Antenna.Comment: Accepted by MNRA