3,027 research outputs found
Calculation of Relativistic Nucleon-Nucleon Potentials in Three-Dimensions
In this paper, we have applied a three-dimensional approach for calculation
of the relativistic nucleon-nucleon potential. The quadratic operator relation
between the non-relativistic and the relativistic nucleon-nucleon interactions
is formulated as a function of relative two-nucleon momentum vectors, which
leads to a three-dimensional integral equation. The integral equation is solved
by the iteration method, and the matrix elements of the relativistic potential
are calculated from non-relativistic ones. Spin-independent Malfliet-Tjon
potential is employed in the numerical calculations, and the numerical tests
indicate that the two-nucleon observables calculated by the relativistic
potential are preserved with high accuracy
Maternal caregivers have confluence of altered cortisol, high reward-driven eating, and worse metabolic health.
Animal models have shown that chronic stress increases cortisol, which contributes to overeating of highly palatable food, increased abdominal fat and lower cortisol reactivity. Few studies in humans have simultaneously examined these trajectories. We examined premenopausal women, either mothers of children with a diagnosis of an autism spectrum disorder (n = 92) or mothers of neurotypical children (n = 91). At baseline and 2-years, we assessed hair cortisol, metabolic health, and reward-based eating. We compared groups cross-sectionally and prospectively, accounting for BMI change. Caregivers, relative to controls, had lower cumulative hair cortisol at each time point, with no decreases over time. Caregivers also had stable levels of poor metabolic functioning and greater reward-based eating across both time points, and evidenced increased abdominal fat prospectively (all ps ≤.05), independent of change in BMI. This pattern of findings suggest that individuals under chronic stress, such as caregivers, would benefit from tailored interventions focusing on better regulation of stress and eating in tandem to prevent early onset of metabolic disease, regardless of weight status
Robotics and Programming Workshops to Stimulate Children's Interest in STEM
IMPACT. 1: Dr. Radin has partnered with community organizations to provide facilities, advertising, registration, and funding so that workshops can be provided without cost to teams. -- 2. Dr. Radin's team has taught these workshops for 4 years, reaching over 1500 elementary and middle school children and their adult mentors. Participants come from Ohio as well as neighboring states of Michigan, Pennsylvania, Indiana and Kentucky.OSU PARTNERS: College of Veterinary Medicine; Department of Veterinary BiosciencesCOMMUNITY PARTNERS: Starbase - Wright Patterson Air Force Base Outreach; iSpace Cincinnati; Rockwell AutomationPRIMARY CONTACT: M. Judith Radin ([email protected])FIRST is an organization that promotes robotics competitions to stimulate children's interest in math and science. Many teams competing in this program are based in elementary and middle schools and available teachers/ mentors often have very limited programming experience, which can result in frustration for both students and mentors. As one of the coaches of a successful robotics team, Dr. Radin helped design an 8-hour interactive programming workshop for elementary and middle school students and mentors
Two-point correlation properties of stochastic "cloud processes''
We study how the two-point density correlation properties of a point particle
distribution are modified when each particle is divided, by a stochastic
process, into an equal number of identical "daughter" particles. We consider
generically that there may be non-trivial correlations in the displacement
fields describing the positions of the different daughters of the same "mother"
particle, and then treat separately the cases in which there are, or are not,
correlations also between the displacements of daughters belonging to different
mothers. For both cases exact formulae are derived relating the structure
factor (power spectrum) of the daughter distribution to that of the mother.
These results can be considered as a generalization of the analogous equations
obtained in ref. [1] (cond-mat/0409594) for the case of stochastic displacement
fields applied to particle distributions. An application of the present results
is that they give explicit algorithms for generating, starting from regular
lattice arrays, stochastic particle distributions with an arbitrarily high
degree of large-scale uniformity.Comment: 14 pages, 3 figure
Cartilage degeneration in the human patellae and its relationship to the mineralisation of the underlying bone
A cluster expansion approach to exponential random graph models
The exponential family of random graphs is among the most widely-studied
network models. We show that any exponential random graph model may
alternatively be viewed as a lattice gas model with a finite Banach space norm.
The system may then be treated by cluster expansion methods from statistical
mechanics. In particular, we derive a convergent power series expansion for the
limiting free energy in the case of small parameters. Since the free energy is
the generating function for the expectations of other random variables, this
characterizes the structure and behavior of the limiting network in this
parameter region.Comment: 15 pages, 1 figur
Extinctions and Correlations for Uniformly Discrete Point Processes with Pure Point Dynamical Spectra
The paper investigates how correlations can completely specify a uniformly
discrete point process. The setting is that of uniformly discrete point sets in
real space for which the corresponding dynamical hull is ergodic. The first
result is that all of the essential physical information in such a system is
derivable from its -point correlations, . If the system is
pure point diffractive an upper bound on the number of correlations required
can be derived from the cycle structure of a graph formed from the dynamical
and Bragg spectra. In particular, if the diffraction has no extinctions, then
the 2 and 3 point correlations contain all the relevant information.Comment: 16 page
Modelling quasicrystals at positive temperature
We consider a two-dimensional lattice model of equilibrium statistical
mechanics, using nearest neighbor interactions based on the matching conditions
for an aperiodic set of 16 Wang tiles. This model has uncountably many ground
state configurations, all of which are nonperiodic. The question addressed in
this paper is whether nonperiodicity persists at low but positive temperature.
We present arguments, mostly numerical, that this is indeed the case. In
particular, we define an appropriate order parameter, prove that it is
identically zero at high temperatures, and show by Monte Carlo simulation that
it is nonzero at low temperatures
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