26,608 research outputs found
ExoMol line lists IV: The rotation-vibration spectrum of methane up to 1500 K
A new hot line list is calculated for CH in its ground electronic
state. This line list, called 10to10, contains 9.8 billion transitions and
should be complete for temperatures up to 1500 K. It covers the wavelengths
longer than 1 m and includes all transitions to upper states with energies
below cm and rotational excitation up to . The
line list is computed using the eigenvalues and eigenfunctions of CH
obtained by variational solution of the Schr\"{o}dinger equation for the
rotation-vibration motion of nuclei employing program TROVE. An ab initio
dipole moment surface and a new 'spectroscopic' potential energy surface are
used. Detailed comparisons with other available sources of methane transitions
including HITRAN, experimental compilations and other theoretical line lists
show that these sources lack transitions both higher temperatures and near
infrared wavelengths. This line list is suitable for modelling atmospheres of
cool stars and exoplanets. It is available from the CDS database as well as at
www.exomol.com.Comment: Submitted to MNRA
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Are personalities genetically determined? Inferences from subsocial spiders.
BACKGROUND:Recent research has revealed that polymorphic behavioral strategies shape intra-and interspecific interactions and contribute to fitness in many animal species. A better understanding of the proximate mechanisms underlying these behavioral syndromes will enhance our grasp this phenomenon. Spiders in the genus Anelosimus exhibit inter-individual behavioral variation on several axes: individuals have consistent responses to stimuli (e.g. bold vs. shy individuals) and they are subsocial (exhibiting extended maternal care and sibling cooperation) across most of their range, but they sometimes form permanent social groups in northern temperate regions. Here, we seek genetic variants associated with boldness and with social structure in a socially polymorphic population of the spider Anelosimus studiosus. We also develop preliminary genomic resources, including a genome assembly and linkage map, that support this and future genomic research on this group. RESULTS:Remarkably, we identify a small genomic scaffold (~ 1200 bp) that harbors seven single nucleotide polymorphisms (SNPs) associated with boldness. Moreover, heterozygotes are less common than expected based on Hardy-Weinberg equilibrium, suggesting that either assortative mating or selection against heterozygotes may be occurring in this system. We find no loci significantly associated with social organization. Our draft genome assembly allows us to localize SNPs of interest in this study and to carry out genetic comparisons with other published genomes, although it remains highly fragmented. CONCLUSIONS:By identifying a locus associated with a well-studied animal personality trait, this study opens up avenues for future research to link behavioral studies of animal personality with genotype and fitness
The ExoMol Atlas of Molecular Opacities
The ExoMol project is dedicated to providing molecular line lists for
exoplanet and other hot atmospheres. The ExoMol procedure uses a mixture of ab
initio calculations and available laboratory data. The actual line lists are
generated using variational nuclear motion calculations. These line lists form
the input for opacity models for cool stars and brown dwarfs as well as for
radiative transport models involving exoplanets. This paper is a collection of
molecular opacities for 52 molecules (130 isotopologues) at two reference
temperatures, 300 K and 2000 K, using line lists from the ExoMol database. So
far, ExoMol line lists have been generated for about 30 key molecular species.
Other line lists are taken from external sources or from our work predating the
ExoMol project. An overview of the line lists generated by ExoMol thus far is
presented and used to evaluate further molecular data needs. Other line lists
are also considered. The requirement for completeness within a line list is
emphasized and needs for further line lists discussed
The Status of Spectroscopic Data for the Exoplanet Characterisation Missions
The status of laboratory spectroscopic data for exoplanet characterisation
missions such as EChO is reviewed. For many molecules (eg H2O, CO, CO2, H3+,
O2, O3) the data are already available. For the other species work is actively
in progress constructing this data. Much of the is work is being undertaken by
ExoMol project (www.exomol.com). This information will be used to construct and
EChO-specific spectroscopic database.Comment: Experimental Astronomy, accepte
Reassessing the Link between Voter Heterogeneity and Political Accountability: A Latent Class Regression Model of Economic Voting
While recent research has underscored the conditioning effect of individual characteristics on economic voting behavior, most empirical studies have failed to explicitly incorporate observed heterogeneity into statistical analyses linking citizens' economic evaluations to electoral choices. In order to overcome these drawbacks, we propose a latent
class regression model to jointly analyze the determinants and influence of economic
voting in Presidential and Congressional elections. Our modeling approach allows us to
better describe the effects of individual covariates on economic voting and to test hypotheses on the existence of heterogeneous types of voters, providing an empirical basis
for assessing the relative validity of alternative explanations proposed in the literature.
Using survey data from the 2004 U.S. Presidential, Senate and House elections, we
and that voters with college education and those more interested in political campaigns
based their vote on factors other than their economic perceptions. In contrast, less educated and interested respondents assigned considerable weight to economic assessments,
with sociotropic jugdgments strongly in
uencing their vote in the Presidential election
and personal financial considerations affecting their vote in House elections. We conclude that the main distinction in the 2004 election was not between `sociotropic' and
`pocketbook' voters, but rather between `economic' and `non-economic' voters
Laboratory spectra of hot molecules: data needs for hot super-Earth exoplanets
The majority of stars are now thought to support exoplanets. Many of those
exoplanets discovered thus far are categorized as rocky objects with an
atmosphere. Most of these objects are however hot due to their short orbital
period. Models suggest that water is the dominant species in their atmospheres.
The hot temperatures are expected to turn these atmospheres into a (high
pressure) steam bath containing remains of melted rock. The spectroscopy of
these hot rocky objects will be very different from that of cooler objects or
hot gas giants. Molecules suggested to be important for the spectroscopy of
these objects are reviewed together with the current status of the
corresponding spectroscopic data. Perspectives of building a comprehensive
database of linelist/cross sections applicable for atmospheric models of rocky
super-Earths as part of the ExoMol project are discussed. The
quantum-mechanical approaches used in linelist productions and their challenges
are summarized.Comment: Molecular Astrophysics (in press) Review article 96 pages, 17
Figures, 2 Tables, 267 reference
ExoMol: molecular line lists for exoplanet and other atmospheres
The discovery of extrasolar planets is one of the major scientific advances
of the last two decades. Hundreds of planets have now been detected and
astronomers are beginning to characterise their composition and physical
characteristics. To do this requires a huge quantity of spectroscopic data most
of which is not available from laboratory studies. The ExoMol project will
offer a comprehensive solution to this problem by providing spectroscopic data
on all the molecular transitions of importance in the atmospheres of
exoplanets. These data will be widely applicable to other problems and will be
used for studies on cool stars, brown dwarfs and circumstellar environments.
This paper lays out the scientific foundations of this project and reviews
previous work in this area.
A mixture of first principles and empirically-tuned quantum mechanical
methods will be used to compute comprehensive and very large rotation-vibration
and rotation-vibration-electronic (rovibronic) line lists. Methodologies will
be developed for treating larger molecules such as methane and nitric acid.
ExoMol will rely on these developments and the use of state-of-the-art
computing.Comment: MNRAS (in press
How has the Louisiana Scholarship Program Affected students? A Comprehensive Summary of Effects After Three Years
School choice reforms comprise a broad category of policies aimed at improving public education through the introduction of market forces that expand customer choice and competition between schools. Here we summarize our research to date on the effects of a large statewide school voucher initiative, the Louisiana Scholarship Program (LSP), and draw the following conclusions: • Overall, participating in the LSP had no statistically significant impact on student English Language Arts (ELA) or math scores after using an LSP scholarship for three years. • The subgroup of students who were lower achieving before applying to the program did show significant gains in ELA after three years of scholarship usage. Students applying to lower grades demonstrated significant losses in math. • Students without disabilities were less likely to be identified to receive special education services if they participated in the LSP than if they did not. Students with disabilities were more likely to be de-identified as requiring special education services if they participated in the private school choice program. • The private schools that chose to participate in the LSP were disproportionately Catholic, had low tuitions, had low enrollments, and served a high percentage of minority students. We discuss these findings in the remainder of this brief and in greater detail in the three accompanying technical reports. Combined with prior evidence, these results are informative about the specific design of voucher and other choice policies and about how the effects of choice evolve over time as programs mature
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