18,166 research outputs found
Laser-induced thermal acoustics: simple accurate gas measurements
Laser-induced thermal acoustics (LITA), an optical four-wave mixing technique, has been used for sensitive measurement of the sound speed, thermal diffusivity, acoustic damping rate, and complex susceptibility of a gas. In LITA, laser-induced acoustic waves scatter laser light into a coherent, modulated signal beam. A simple expression accurately describes the signal. Atmospheric sound speeds accurate to 0.5% and transport properties accurate to 30% have been measured in a single shot without calibration. LITA spectra have been taken of weak spectral lines of NO2 in concentrations of less than 50 parts in 10^9. Signal reflectivities up to 10^4 are estimated
Educating for the Gaming Industry: Need, Profile, and Suggested Schema
As legalized gambling becomes increasingly widespread and competitive, operators seek employees who understand its unique culture and demands. Today, few baccalaureate programs offer gaming management education. Gaming subject areas for college programs span three content spheres: (a) gaming and games themselves; (b) gaming interfaces with other hospitality subjects (lodging, accounting); and (c) the gaming/hospitality environment (regulation, economics). In a given academic program, gaming content integration can be measured along a continuum, from nonexistent, to somewhat integrated within existing courses, to comprising a central educational focus
Poison Frog Colors Are Honest Signals Of Toxicity, Particularly For Bird Predators
Antipredator defenses and warning signals typically evolve in concert. However, the extensive variation across taxa in both these components of predator deterrence and the relationship between them are poorly understood. Here we test whether there is a predictive relationship between visual conspicuousness and toxicity levels across 10 populations of the color-polymorphic strawberry poison frog, Dendrobates pumilio. Using a mouse-based toxicity assay, we find extreme variation in toxicity between frog populations. This variation is significantly positively correlated with frog coloration brightness, a viewer-independent measure of visual conspicuousness (i.e., total reflectance flux). We also examine conspicuousness from the view of three potential predator taxa, as well as conspecific frogs, using taxon-specific visual detection models and three natural background substrates. We find very strong positive relationships between frog toxicity and conspicuousness for bird-specific perceptual models. Weaker but still positive correlations are found for crab and D. pumilio conspecific visual perception, while frog coloration as viewed by snakes is not related to toxicity. These results suggest that poison frog colors can be honest signals of prey unpalatability to predators and that birds in particular may exert selection on aposematic signal design.Integrative Biolog
Characteristics of the Termination Shock: Insights from Voyager
We examine the energy spectra obtained from the cosmic ray instrument on the Voyager 1 spacecraft during 2002/215 through 2005/60. We find that the energy spectra of protons below ~20 MeV often resemble two power laws with a relatively hard index at low energies and a softer index at higher energies. The point of intersection of the two power laws is ~3 MeV. Beginning in 2005, the low-energy index is typically –1.5, corresponding to a shock strength (compression ratio) of 2.5. We attribute these characteristics to a restricted region of the solar wind termination shock that is sporadically connected to the Voyager 1 spacecraft by the interplanetary magnetic field. The absence of significant spectral variability in 2005 suggests that Voyager 1 entered a region with minimal spatial gradients of the lowest energy ions
An Evolutionary View of the Critical Functions of Slot Machine Technology
The U.S. gaming industry has grown from its infancy in the early 1930s to a maturing giant in the 1990s. With this growth has come an evolution in management functions associated with one of the major components of casino operations, the slot department. These functions; counting, analysis, security, maintenance, and marketing, have evolved through an iterative process of technology; applying science to enhance functionality. This paper traces the expanding applications of gaming technologies, and provides a framework for understanding the past, present and future uses of technology in casino slot operation
Dissolved Oxygen Monitoring in Kings River and Leatherwood Creek
The Clean Water Act (CWA) establishes the basic structure used to regulate water quality. Under the CWA, States are required to assess water bodies relative to water‐quality standards and designated beneficial uses and then to submit lists of impaired bodies every other year to the US Environmental Protection Agency (USEPA). In 2015, at least 4,800 water bodies were listed as impaired by dissolved oxygen across the US (USEPA, 2015). Aquatic species like fish and macroinvertebrates depend on adequate dissolved oxygen for survival. Low dissolved oxygen can lead to fish kills, reduced aquatic diversity, and nuisance smells from anaerobic conditions – ultimately, low dissolved oxygen concentrations result in water bodies not being able to meet the aquatic life designated use
Sustainability Standards and Stakeholder Engagement: Lessons From Carbon Markets
Stakeholders play an increasingly active role in private governance, including development of standards for measuring sustainability. Building on prior studies focused on standards and stakeholder engagement, we use an innovation management theoretical lens to compare stakeholder engagement and standards developed in two carbon markets: the Climate Action Reserve and the U.N.’s Clean Development Mechanism. We develop and test hypotheses regarding how different processes of stakeholder engagement in standard development affect the number, identity, and age of stakeholders involved, as well as the variation and quality of the resulting standards. In doing so, we contribute to the growing literature on stakeholder engagement in developing sustainability standards
The anomalous cosmic-ray component
This brief report is intended to update the anomalous component section of the summary report of the galactic cosmic-ray working group (Mewaldt et al., 1987), which was drafted at the March 1987 Workshop on the Interplanetary Charged Particle Environment at the Jet Propulsion Laboratory. The description of the spectrum of the anomalous cosmic-ray component is contained in section 3.3 of that report. That description is based on data analyzed through day 310 of 1986, and in it we proposed that the energy spectrum of the various species of the anomalous component could be derived by scaling from two generic spectra. Two generic spectra were required because the energy spectrum of the anomalous component changed shape near the time of the solar magnetic field reversal in 1980. These two generic spectra are shown in Figure 2 of the summary report
Ultracold neutral plasma expansion in two dimensions
We extend an isothermal thermal model of ultracold neutral plasma expansion
to systems without spherical symmetry, and use this model to interpret new
fluorescence measurements on these plasmas. By assuming a self-similar
expansion, it is possible to solve the fluid equations analytically and to
include velocity effects to predict the fluorescence signals. In spite of the
simplicity of this approach, the model reproduces the major features of the
experimental data
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