2,145 research outputs found
Gas-solid coexistence of adhesive spheres
In this note we investigate using basic free energy considerations the
location of the gas-liquid critical point with respect to solidification for
narrow attractive interactions down to the Baxter limit. Possible experimental
and simulation realizations leading to a stable critical point are briefly
discussed.Comment: 2 pages, 2 figures, submitte
Dynamical Heterogeneity and Nonlinear Susceptibility in Short-Ranged Attractive Supercooled Liquids
Recent work has demonstrated the strong qualitative differences between the
dynamics near a glass transition driven by short-ranged repulsion and one
governed by short-ranged attraction. Here, we study in detail the behavior of
non-linear, higher-order correlation functions that measure the growth of
length scales associated with dynamical heterogeneity in both types of systems.
We find that this measure is qualitatively different in the repulsive and
attractive cases with regards to the wave vector dependence as well as the time
dependence of the standard non-linear four-point dynamical susceptibility. We
discuss the implications of these results for the general understanding of
dynamical heterogeneity in glass-forming liquids.Comment: 5 pages, 3 figure
Preliminary Constraints on 12C(alpha,gamma)16O from White Dwarf Seismology
For many years, astronomers have promised that the study of pulsating white
dwarfs would ultimately lead to useful information about the physics of matter
under extreme conditions of temperature and pressure. In this paper we finally
make good on that promise. Using observational data from the Whole Earth
Telescope and a new analysis method employing a genetic algorithm, we
empirically determine that the central oxygen abundance in the
helium-atmosphere variable white dwarf GD 358 is 84+/-3 percent. We use this
value to place preliminary constraints on the 12C(alpha,gamma)16O nuclear
reaction cross-section. More precise constraints will be possible with
additional detailed simulations. We also show that the pulsation modes of our
best-fit model probe down to the inner few percent of the stellar mass. We
demonstrate the feasibility of reconstructing the internal chemical profiles of
white dwarfs from asteroseismological data, and find an oxygen profile for GD
358 that is qualitatively similar to recent theoretical calculations.Comment: Accepted for publication in the Astrophysical Journal, 7 pages, 6
figures, 2 tables, uses emulateapj5.st
Phase behavior and far-from-equilibrium gelation of charged attractive colloids
In this Rapid Communication we demonstrate the applicability of an augmented
Gibbs ensemble Monte Carlo approach for the phase behavior determination of
model colloidal systems with short-ranged depletion attraction and long-ranged
repulsion. This technique allows for a quantitative determination of the phase
boundaries and ground states in such systems. We demonstrate that gelation may
occur in systems of this type as the result of arrested microphase separation,
even when the equilibrium state of the system is characterized by compact
microphase structures.Comment: 5 pages, 3 figures, final versio
[N]pT ensemble and finite-size scaling study of the GEM-4 critical isostructural transition
First-order transitions of system where both lattice site occupancy and
lattice spacing fluctuate, such as cluster crystals, cannot be efficiently
studied by traditional simulation methods. These methods necessarily fix one of
these two degrees of freedom, but this difficulty is surmounted by the
generalized [N]pT ensemble [J. Chem. Phys. 136, 214106 (2012)]. Here it is
shown that histogram reweighting and the [N]pT ensemble can be used to study an
isostructural transition between cluster crystals of different occupancy in the
generalized exponential model of index 4 (GEM-4). Extending this scheme to
finite-size scaling studies also allows to accurately determine the critical
point parameters and to verify that it belongs to the Ising universality class.Comment: 5 pages, 4 figure
The Influence of a Centrally-Procured School Food Program on Consumption and Instances of Fruits and Vegetables in School-Age Children
Background: In Canada, 70% of youth are not meeting the recommended five servings of fruits and vegetables (FV) daily. School nutrition programs are one strategy for improving dietary habits in youth.
Methods: A two-year pilot cluster randomized controlled trial was implemented within Southwestern Ontario to assess how a ten-week centrally-procured school food program (CPSFP) influences students’ consumption and instances of FV compared to the traditional school nutrition program (TSNP).
Results: Children were 9-13 years of age; 30 schools received the CPSFP and 30 received the TSNP. Vegetable consumption did not change with the CPSFP (mean=0.0; SD=1.0) or the TSNP (mean=0.0; SD=1.0; p=0.94). Fruit consumption did not change with the CPSFP (mean=0.0; SD=1.4) and decreased by 0.1 servings (SD=1.4) with the TSNP (p=0.06). Instances of vegetables and fruit were similar between groups.
Conclusions: The CPSFP resulted in no significant change in consumption or instances of FV
Predictors of women\u27s workplace conflict management styles
This study examined empirically women’s interpersonal workplace conflict management styles. This study’s purpose was to add to the knowledge base of women and conflict management. The research question was to determine whether social characteristics such as feminism, race, age, single head of household status, religion, and social class explain differences in conflict management among women. Research Hypotheses 1 through 6 were that significant differences based on feminism, age, race, single head of household, social class, and religion would be found among the study’s respondents in their choice of five styles of conflict management. Research Hypothesis 7 was that feminism would increase the amount of explained variance of the above socio-demographic model. A questionnaire composed of self-report responses on conflict management styles, feminist attitudes, and social demographics was administered to a sample consisting of three hundred and thirty-one women who represent a variety of socio-demographic groups in the Southeastern Michigan area. The mean age of the sample was 34.5 years, 26% were African-Americans, 42% identified themselves as working class and 26% were single heads of households. Rahim’s ROCI-II (Form C, 1983) Conflict Inventory-II was used to measure conflict management styles, and feminist orientation was measured by Morgan’s Liberal Feminist Attitude and Ideology Scale (1996). In the Rahim inventory the respondents were asked to respond to two conflict scenarios, one a female/female conflict and the other a female/male conflict. The bivariate and multivariate analyses showed limited support for the research hypotheses. The findings revealed significant effects for 1) feminism on the Integrating, Avoiding, and Obliging Conflict Management Styles; 2) age on Compromising, Dominating, and Avoiding Styles in the female/female conflict and the Obliging Style in the female/male conflict scenario; 3) African-Americans on the Compromising Style in the female/female conflict scenario and Caucasians on the Compromising Style in the female/female conflict scenario, and the Avoiding and Obliging Styles in both the conflict scenarios. No support was found for the single head of household, social class, and religion hypotheses. Finally, the findings supported the hypothesis that feminism would increase the explained variance of the socio-demographic model on the Avoiding, Integrating, and Obliging Conflict Management Styles
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