31,940 research outputs found
The development of a tape recording for appreciative listening to choral speaking in the fourth grade
Thesis (Ed.M.)--Boston Universit
Genus two mutant knots with the same dimension in knot Floer and Khovanov homologies
We exhibit an infinite family of knots with isomorphic knot Heegaard Floer
homology. Each knot in this infinite family admits a nontrivial genus two
mutant which shares the same total dimension in both knot Floer homology and
Khovanov homology. Each knot is distinguished from its genus two mutant by both
knot Floer homology and Khovanov homology as bigraded groups. Additionally, for
both knot Heegaard Floer homology and Khovanov homology, the genus two mutation
interchanges the groups in -gradings and .Comment: Information about -graded homology has been changed along
with statement of Theorem 1 and Table 1. Significant changes to Section
Surgery on links of linking number zero and the Heegaard Floer -invariant
We study Heegaard Floer homology and various related invariants (such as the
-function) for two-component L-space links with linking number zero. For
such links, we explicitly describe the relationship between the -function,
the Sato-Levine invariant and the Casson invariant. We give a formula for the
Heegaard Floer -invariants of integral surgeries on two-component L-space
links of linking number zero in terms of the -function, generalizing a
formula of Ni and Wu. As a consequence, for such links with unknotted
components, we characterize L-space surgery slopes in terms of the
-invariants of the knots obtained from blowing down the components.
We give a proof of a skein inequality for the -invariants of
surgeries along linking number zero links that differ by a crossing change. We
also describe bounds on the smooth four-genus of links in terms of the
-function, expanding on previous work of the second author, and use these
bounds to calculate the four-genus in several examples of links.Comment: This version accepted for publication in Quantum Topolog
Observational Tests of the Properties of Turbulence in the Very Local Interstellar Medium
The Very Local Interstellar Medium (VLISM) contains clouds which consist of
partially-ionized plasma. These clouds can be effectively diagnosed via high
resolution optical and ultraviolet spectroscopy of the absorption lines they
form in the spectra of nearby stars. Among the information provided by these
spectroscopic measurements are the root-mean-square velocity fluctuation due to
turbulence in these clouds and the ion temperature, which may be partially
determined by dissipation of turbulence. We consider whether this turbulence
resembles the extensively studied and well-diagnosed turbulence in the solar
wind and solar corona. Published observations are used to determine if the
velocity fluctuations are primarily transverse to a large-scale magnetic field,
whether the temperature perpendicular to the large scale field is larger than
that parallel to the field, and whether ions with larger Larmor radii have
higher temperatures than smaller gyroradius ions. Although a thorough
investigation of the data is underway, a preliminary examination of the
published data shows neither evidence for anisotropy of the velocity
fluctuations or temperature, nor Larmor radius-dependent heating. These results
indicate differences between solar wind and Local Cloud turbulence.Comment: Paper submitted to Nonlinear Processes in Geophysic
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Adolescent Physical Education and Physical Activity in California
Based on 2007 California Health Interview Survey data, examines participation in physical education and other physical activity among adolescents ages 12 to 17 by gender and county, and implications for health outcomes. Makes policy recommendations
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