1,944 research outputs found
Definition of Throw-Away Detectors (TADs) and VLF antenna for the AMPS laboratory
A Throw Away Detector (TAD)/subsatellite to be used as an experiment platform for the test flights to map the EMI from the shuttle and during the AMPS science flights is defined. A range of instrument platforms of varying capabilities is examined with emphasis on the EMI test vehicle. The operational support requirements of TAD/subsatellites are determined. The throw away detector is envisioned as a simple instrument package for supporting specific experiments
Fear and Greed in Tax Policy: A Qualitative Research Agenda
While there is a general consensus that most people dislike paying taxes, more empirical data is needed to determine how, and to what extent, tax aversion plays a role in taxpayer behavior. If tax aversion occurs at significant levels, it becomes important to isolate and explore the constitutive elements of that aversion. A better understanding of the causes and components of tax aversion could spur useful innovation in tax design. In this Essay, we survey and mine existing bodies of empirical work for the insights they might bring to bear on these questions, while constructing a qualitative research agenda that begins to fill the remaining gaps. To focus our inquiry, we concentrate primarily on the federal income tax
Fear and Greed in Tax Policy: A Qualitative Research Agenda
While there is a general consensus that most people dislike paying taxes, more empirical data is needed to determine how, and to what extent, tax aversion plays a role in taxpayer behavior. If tax aversion occurs at significant levels, it becomes important to isolate and explore the constitutive elements of that aversion. A better understanding of the causes and components of tax aversion could spur useful innovation in tax design. In this Essay, we survey and mine existing bodies of empirical work for the insights they might bring to bear on these questions, while constructing a qualitative research agenda that begins to fill the remaining gaps. To focus our inquiry, we concentrate primarily on the federal income tax
A New Species of \u3ci\u3eEuphorbia\u3c/i\u3e Subgenus \u3ci\u3eChamaesyce\u3c/i\u3e Section \u3ci\u3eAlectoroctonum\u3c/i\u3e (Euphorbiaceae) From Limestone Hills of Wayne County, Mississippi
As part of a project to document the vascular flora of Wayne County, Mississippi, an unusual Euphorbia, which keys to the Euphorbia corollata complex, was encountered in mature hardwood forests in limestone regions. Unlike typical E. corollata and E. pubentissima, these individuals have long petioles (0.4–1.2 cm), oval to ovate leaves, short stature, small cyathia, small seeds, and a different phenology. In order to test species boundaries, morphological character differences were explored using principal component analysis (PCA), and additional characters were gathered from plastid (rpL16) and nuclear (ITS) DNA data of the unusual individuals as well as of E. corollata, E. pubentissima, and several other species of Euphorbia subgenus Chamaesyce section Alectoroctonum. The PCA indicates that the individuals are morphological outliers, and phylogenetic analyses of the DNA data indicate that the individuals have a unique haplotype different from E. corollata or E. pubentissima and are rather more closely related to E. mercurialina, a species not in the E. corollata complex but which occurs in similar mesic habitat in eastern Tennessee and neighboring Alabama, Georgia, and Kentucky. These data support the hypothesis that these unusual individuals represent a new species. Neither the PCA nor the phylogenetic analysis of DNA data reveals any differences between E. corollata and E. pubentissima
Topological Sector Fluctuations and Curie Law Crossover in Spin Ice
At low temperatures, a spin ice enters a Coulomb phase - a state with
algebraic correlations and topologically constrained spin configurations. In
Ho2Ti2O7, we have observed experimentally that this process is accompanied by a
non-standard temperature evolution of the wave vector dependent magnetic
susceptibility, as measured by neutron scattering. Analytical and numerical
approaches reveal signatures of a crossover between two Curie laws, one
characterizing the high temperature paramagnetic regime, and the other the low
temperature topologically constrained regime, which we call the spin liquid
Curie law. The theory is shown to be in excellent agreement with neutron
scattering experiments. On a more general footing, i) the existence of two
Curie laws appears to be a general property of the emergent gauge field for a
classical spin liquid, and ii) sheds light on the experimental difficulty of
measuring a precise Curie-Weiss temperature in frustrated materials; iii) the
mapping between gauge and spin degrees of freedom means that the susceptibility
at finite wave vector can be used as a local probe of fluctuations among
topological sectors.Comment: 10 pages, 5 figure
- …