3,110 research outputs found
Longevity and Weight Loss of Free-flying Male Cecropia Moths, \u3ci\u3eHyalophora Cecropia\u3c/i\u3e (Lepidoptera: Saturniidae)
During their spring flight season, free-ranging male cecropia moths lived a maximum of 12 days (one of 124 recaptured moths of 387 released moths). The number of survivors declined precipitiously after day five; five to seven days is probably the usual life span. The recaptured moths did not have different initial weights than those that were not recaptured. The larger the moth the more absolute weight it lost and the faster it lost weight during the first few days. A moth lost about 20% of its weight during the first night of flight and accumulated about a 40% weight loss during the remainder of its life
Boolean decision problems with competing interactions on scale-free networks: Critical thermodynamics
We study the critical behavior of Boolean variables on scale-free networks
with competing interactions (Ising spin glasses). Our analytical results for
the disorder-network-decay-exponent phase diagram are verified using Monte
Carlo simulations. When the probability of positive (ferromagnetic) and
negative (antiferromagnetic) interactions is the same, the system undergoes a
finite-temperature spin-glass transition if the exponent that describes the
decay of the interaction degree in the scale-free graph is strictly larger than
3. However, when the exponent is equal to or less than 3, a spin-glass phase is
stable for all temperatures. The robustness of both the ferromagnetic and
spin-glass phases suggests that Boolean decision problems on scale-free
networks are quite stable to local perturbations. Finally, we show that for a
given decay exponent spin glasses on scale-free networks seem to obey
universality. Furthermore, when the decay exponent of the interaction degree is
larger than 4 in the spin-glass sector, the universality class is the same as
for the mean-field Sherrington-Kirkpatrick Ising spin glass.Comment: 14 pages, lots of figures and 2 table
Phylogenetics: Which was first, TSD or GSD?
The basic challenge of evolutionary biology is to explain variation or the lack thereof, be it phenotypic, genetic, phy· logenetic, spatial, temporal, and so on. To illustrate, one gross generalization is that phenotypic traits we think of as being very important to organisms tend to be highly conserved (e.g .. binocular vision in vertebrates). probably because the genomic and developmental underpinnings are essentially fiXed. Thus, one striking feature about sex-determining mechanisms (SDMs), a fundamental aspect of sexual or· ganisms, is the enormous variety (Bull1983)
SOIL QUALITY ATTRIBUTE TIME PATHS: OPTIMAL LEVELS AND VALUES
We develop a dynamic soil quality model to evaluate optimal cropping systems in the northern Great Plains. Modeling soil quality attributes is feasible, and attribute model results apply to a wide range of soils. A crop production system with continuous spring wheat and direct planting is the most profitable system. This system has low soil erosion and high quality attributes, indicating the benefits of increased soil quality exceed the higher maintenance costs. On-site value of additional soil organic carbon (OC) ranges from 4/ton OC/hectare/year. These values for soil OC impact the optimum tillage practice, but not the crop rotation.Crop Production/Industries,
Concentration fields near air-water interfaces during interfacial mass transport: oxygen transport and random square wave analysis
Mass transfer across a gas-liquid interface was studied theoretically and experimentally, using transfer of oxygen into water as the gas-liquid system. The experimental results support the conclusions of a theoretical description of the concentration field that uses random square waves approximations. The effect of diffusion over the concentration records was quantified. It is shown that the peak of the normalized rms concentration fluctuation profiles must be lower than 0.5, and that the position of the peak of the rms value is an adequate measure of the thickness of the diffusive layer. The position of the peak is the boundary between the regions more subject to molecular diffusion or to turbulent transport of dissolved mass
Critical behavior and universality in Levy spin glasses
Using large-scale Monte Carlo simulations that combine parallel tempering
with specialized cluster updates, we show that Ising spin glasses with
Levy-distributed interactions share the same universality class as Ising spin
glasses with Gaussian or bimodal-distributed interactions. Corrections to
scaling are large for Levy spin glasses. In order to overcome these and show
that the critical exponents agree with the Gaussian case, we perform an
extended scaling of the two-point finite size correlation length and the spin
glass susceptibility. Furthermore, we compute the critical temperature and
compare its dependence on the disorder distribution width to recent analytical
predictions [J. Stat. Mech. (2008) P04006].Comment: 7 pages, 6 figures, 2 table
Improving productivity through work measurement : a cooperative approach; Management advisory services practice aids. Technical consulting practice aid, 09
https://egrove.olemiss.edu/aicpa_guides/1097/thumbnail.jp
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