Why is timing of bird migration advancing when individuals are not?

Recent advances in spring arrival dates have been reported in many migratory species but the mechanism driving these advances is unknown. As population declines are most widely reported in species that are not advancing migration, there is an urgent need to identify the mechanisms facilitating and constraining these advances. Individual plasticity in timing of migration in response to changing climatic conditions is commonly proposed to drive these advances but plasticity in individual migratory timings is rarely observed. For a shorebird population that has significantly advanced migration in recent decades, we show that individual arrival dates are highly consistent between years, but that the arrival dates of new recruits to the population are significantly earlier now than in previous years. Several mechanisms could drive advances in recruit arrival, none of which require individual plasticity or rapid evolution of migration timings. In particular, advances in nest-laying dates could result in advanced recruit arrival, if benefits of early hatching facilitate early subsequent spring migration. This mechanism could also explain why arrival dates of short-distance migrants, which generally return to breeding sites earlier and have greater scope for advance laying, are advancing more rapidly than long-distance migrants

Potts-Percolation-Gauss Model of a Solid

We study a statistical mechanics model of a solid. Neighboring atoms are connected by Hookian springs. If the energy is larger than a threshold the "spring" is more likely to fail, while if the energy is lower than the threshold the spring is more likely to be alive. The phase diagram and thermodynamic quantities, such as free energy, numbers of bonds and clusters, and their fluctuations, are determined using renormalization-group and Monte-Carlo techniques.Comment: 10 pages, 12 figure

Numerical Latent Heat Observation of the q=5 Potts Model

Site energy of the five-state ferromagnetic Potts model is numerically calculated at the first-order transition temperature using corner transfer matrix renormalization group (CTMRG) method. The calculated energy of the disordered phase $U^{+}$ is clearly different from that of the ordered phase $U^{-}$. The obtained latent heat $L = U^{-} - U^{+}$ is 0.027, which quantitatively agrees with the exact solution.Comment: 2 pages, Latex(JPSJ style files are included), 2 ps figures, submitted to J. Phys. Soc. Jpn.(short note

Running App "Zombies, Run!" Users' Engagement with Physical Activity: A Qualitative Study

Introduction: Sufficient physical activity (PA) is important for all aspects of health. Smartphone apps and the use of gamification, such as narrative-based augmented reality (AR), have a great potential to engage a variety of people in more PA. Zombies, Run! (ZR) is the world's most popular running exergame app and therefore a suitable model to understand what users find engaging. / Objective: To understand people's motivation and experience of using a narrative-based AR exergame app ZR for PA. / Materials and Methods: ZR users were randomly selected for interview from a quantitative ZR user's survey. Interviews which were guided by a semistructured topic guide were audio-recorded, transcribed, and analyzed using inductive and deductive thematic analysis. / Results: Participants were 15 males and 15 females aged 16–53 years (mean = 36, SD = 10), from 13 countries, with the largest proportions from the United States (30%) and United Kingdom (23%). The majority (73%) used ZR while running, followed by cycling and walking. Four overarching themes that emerged were: “Reasons for starting and staying with ZR,” “Preferred features,” “Perceived effects of ZR,” and “Pros and cons of the app.” Sixteen subthemes included the attraction of gamification and narrative appeal, desire to add something fun to PA, or to distract from the negative physiological effects of PA. Users' favorite features were the feelings of immersion and presence through narrative, story line, and characters. The narrative motivated participants to engage in PA for longer sessions and encouraged long-term use. / Conclusions: This study identified a number of factors that users found attractive in an AR running exergame, particularly narrative. Our findings suggest that ZR may engage people in exercise by modifying their perception of PA through a story line or narrative, dissociating the players from the effort of exertion. AR narrative-based apps may be an effective way of engaging people with health-related behaviors or habit-forming activities

Gas-plasma compressional wave coupling by momentum transfer

Pressure disturbances in a gas-plasma mixed fluid will result in a hybrid response, with magnetosonic plasma waves coupled to acoustic waves in the neutral gas. In the analytical and numerical treatment presented here, we demonstrate the evolution of the total fluid medium response under a variety of conditions, with the gas-plasma linkage achieved by additional coupling terms in the momentum equations of each species. The significance of this treatment lies in the consideration of density perturbations in such fluids: there is no 'pure' mode response, only a collective one in which elements of the characteristics of each component are present. For example, an initially isotropic gas sound wave can trigger an anisotropic magnetic response in the plasma, with the character of each being blended in the global evolution. Hence sound waves do not remain wholly isotropic, and magnetic responses are less constrained by pure magnetoplasma dynamics

Monte Carlo Simulations of Conformal Theory Predictions for the 3-state Potts and Ising Models

The critical properties of the 2D Ising and 3-state Potts models are investigated using Monte Carlo simulations. Special interest is given to measurement of 3-point correlation functions and associated universal objects, i.e. structure constants. The results agree well with predictions coming from conformal field theory confirming, for these examples, the correctness of the Coulomb gas formalism and the bootstrap method.Comment: 11 pages, 6 Postscript figures, uses Revte

Internal Energy of the Potts model on the Triangular Lattice with Two- and Three-body Interactions

We calculate the internal energy of the Potts model on the triangular lattice with two- and three-body interactions at the transition point satisfying certain conditions for coupling constants. The method is a duality transformation. Therefore we have to make assumptions on uniqueness of the transition point and that the transition is of second order. These assumptions have been verified to hold by numerical simulations for q=2, 3 and 4, and our results for the internal energy are expected to be exact in these cases.Comment: 9 pages, 4 figure