Blatant benevolence and conspicuous consumption: When romantic motives elicit strategic costly signals

Conspicuous displays of consumption and benevolence might serve as “costly signals ” of desirable mate qualities. If so, they should vary strategically with manipulations of mating-related motives. The authors examined this possibility in 4 experiments. Inducing mating goals in men increased their willingness to spend on conspicuous luxuries but not on basic necessities. In women, mating goals boosted public—but not private—helping. Although mating motivation did not generally inspire helping in men, it did induce more helpfulness in contexts in which they could display heroism or dominance. Conversely, although mating motivation did not lead women to conspicuously consume, it did lead women to spend more publicly on helpful causes. Overall, romantic motives seem to produce highly strategic and sex-specific self-presentations best understood within a costly signaling framework. Key words: costly signaling, altruism, conspicuous consumption, mating goals, self-presentation We should often blush at our noblest deeds if the world were to see all their underlying motives.—Francois de La Rochefoucauld On Valentine’s Day 2003, America’s leading authority on phi-lanthropy announced that real estate mogul Donald Trump had pledged $1 million to charity (Foundation Center, 2003). A fe

GRB 081028 and its late-time afterglow re-brightening

‘The definitive version is available at www3.interscience.wiley.com '. Copyright Royal Astronomical SocietySwift captured for the first time a smoothly rising X-ray re-brightening of clear non-flaring origin after the steep decay in a long gamma-ray burst (GRB): GRB 081028. A rising phase is likely present in all GRBs but is usually hidden by the prompt tail emission and constitutes the first manifestation of what is later to give rise to the shallow decay phase. Contemporaneous optical observations reveal a rapid evolution of the injection frequency of a fast cooling synchrotron spectrum through the optical band, which disfavours the afterglow onset (start of the forward shock emission along our line of sight when the outflow is decelerated) as the origin of the observed re-brightening. We investigate alternative scenarios and find that the observations are consistent with the predictions for a narrow jet viewed off-axis. The high on-axis energy budget implied by this interpretation suggests different physical origins of the prompt and (late) afterglow emission. Strong spectral softening takes place from the prompt to the steep decay phase: we track the evolution of the spectral peak energy from the γ-rays to the X-rays and highlight the problems of the high latitude and adiabatic cooling interpretations. Notably, a softening of both the high and low spectral slopes with time is also observed. We discuss the low on-axis radiative efficiency of GRB 081028 comparing its properties against a sample of Swift long GRBs with secure Eγ,iso measurements.Peer reviewe

A New Approach to Background Subtraction in Low-Energy Neutrino Experiments

We discuss a new method to extract neutrino signals in low energy experiments. In this scheme the symmetric nature of most backgrounds allows for direct cancellation from data. The application of this technique to the Palo Verde reactor neutrino oscillation experiment allowed us to reduce the measurement errors on the anti-neutrino flux from $\sim 20$% to $\sim 10$%. We expect this method to substantially improve the data quality in future low background experiments such as KamLAND and LENS.Comment: 7 pages, 2 figure

High Temperature Expansions and Dynamical Systems

We develop a resummed high-temperature expansion for lattice spin systems with long range interactions, in models where the free energy is not, in general, analytic. We establish uniqueness of the Gibbs state and exponential decay of the correlation functions. Then, we apply this expansion to the Perron-Frobenius operator of weakly coupled map lattices.Comment: 33 pages, Latex; [email protected]; [email protected]

Socioeconomic drivers of illegal bushmeat hunting in a Southern African Savanna

Illegal bushmeat hunting of economically and ecologically valuable wildlife populations is emerging as a threat across African savannas. Due to the cryptic nature of illegal hunting, little information exists on the drivers of the bushmeat industry. Here we report on the socioeconomic drivers identified in a broader investigation into illegal bushmeat hunting in rural villages around a southern African savanna ecosystem, the Okavango Delta, Botswana. We conducted interviews with bushmeat hunters and heads of rural households about hunting activities, rural livelihoods, attitudes towards wildlife, and market characteristics of illegal bushmeat. Using generalized linear models, we identified and investigated a set of independent variables that characterize illegal-hunter households. Results revealed that compared to non-hunter households, illegal hunter households (n = 119, 25% of the sample) lived in closer proximity to wildlife, were more likely to farm crops, and more often received income from formal employment by at least one household member. Bushmeat hunting was positively correlated with livestock wealth but not associated with household income. Only 11.4% (n = 44) of non-hunter households reported purchasing bushmeat. Most households (84%) reported incurring costs associated with living near wildlife (e.g., damages to crops or livestock), with no difference between hunter and non-hunter households. Hunters were more likely to say they valued wildlife. We conclude that bushmeat hunting in Botswana is generally supplemental to household core income sources rather than essential for subsistence. We propose two interventions to counter the negative impacts of illegal hunting on the region's lucrative wildlife-based economy: 1) more effective law enforcement that imposes costs for hunting illegally, and 2) development of alternative wildlife-based revenue streams that motivate communities to conserve wildlife.The Food and Agriculture Organization of the United Nations provided the majority of funding for this research under Technical Cooperation Programme project TCP/BOT/3501. The study was also supported by Panthera and the Botswana Predator Conservation Trust. JRBM was supported in part by National Science Foundation Coupled Human and Natural Systems Grant 115057.http://www.elsevier.com/locate/biocon2019-10-01hj2018Zoology and Entomolog

Scaling laws for the 2d 8-state Potts model with Fixed Boundary Conditions

We study the effects of frozen boundaries in a Monte Carlo simulation near a first order phase transition. Recent theoretical analysis of the dynamics of first order phase transitions has enabled to state the scaling laws governing the critical regime of the transition. We check these new scaling laws performing a Monte Carlo simulation of the 2d, 8-state spin Potts model. In particular, our results support a pseudo-critical beta finite-size scaling of the form beta(infinity) + a/L + b/L^2, instead of beta(infinity) + c/L^d + d/L^{2d}. Moreover, our value for the latent heat is 0.294(11), which does not coincide with the latent heat analytically derived for the same model if periodic boundary conditions are assumed, which is 0.486358...Comment: 10 pages, 3 postscript figure

Charge-Symmetry Breaking and the Two-Pion-Exchange Two-Nucleon Interaction

Charge-symmetry breaking in the nucleon-nucleon force is investigated within an effective field theory, using a classification of isospin-violating interactions based on power-counting arguments. The relevant charge-symmetry-breaking interactions corresponding to the first two orders in the power counting are discussed, including their effects on the 3He-3H binding-energy difference. The static charge-symmetry-breaking potential linear in the nucleon-mass difference is constructed using chiral perturbation theory. Explicit formulae in momentum and configuration spaces are presented. The present work completes previously obtained results.Comment: 15 pages, 2 figure

Thermodynamics and collapse of self-gravitating Brownian particles in D dimensions

We address the thermodynamics (equilibrium density profiles, phase diagram, instability analysis...) and the collapse of a self-gravitating gas of Brownian particles in D dimensions, in both canonical and microcanonical ensembles. In the canonical ensemble, we derive the analytic form of the density scaling profile which decays as f(x)=x^{-\alpha}, with alpha=2. In the microcanonical ensemble, we show that f decays as f(x)=x^{-\alpha_{max}}, where \alpha_{max} is a non-trivial exponent. We derive exact expansions for alpha_{max} and f in the limit of large D. Finally, we solve the problem in D=2, which displays rather rich and peculiar features

Congruence between Voters and Parties:The Role of Party-Level Issue Salience

First published online: 25 February 2020The level of congruence between parties and their voters can vary greatly from one policy issue to another, which raises questions regarding the effectiveness of political representation. We seek to explain variation in party–voter congruence across issues and parties. We focus on the hypotheses that (1) average proximity between the positions of voters and the party they vote for will be highest on the issues that the party emphasises in the election campaign and that (2) this relationship will be stronger for niche parties. We test these hypotheses using data on the policy preferences of voters, party positions, party attention profiles and salience on concrete policy issues in four countries: The Netherlands, Ireland, Germany and Sweden. Overall, we find that voter–party proximity tends to be higher on issues that the party emphasises. As these are the issues where parties typically have the greatest policy impact, this implies that the quality of representation is highest where it matters most. There is some limited evidence that the positive relationship between issue salience and proximity is stronger for niche parties. In sum, the quality of policy representation varies strongly with party-level issue salience and to a lesser extent with the type of political party