A5011120546- Astro and Planetary Science
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Gamma-ray bursts and supernovae
- Planetary Science and Exploration
- Solar and Space Plasma Dynamics
- Cosmology and Gravitation Theories
- Dark Matter and Cosmic Phenomena
- Scientific Research and Discoveries
- Nuclear physics research studies
- Historical and Architectural Studies
- History and Developments in Astronomy
- Historical Astronomy and Related Studies
- Astronomical and nuclear sciences
- Space Satellite Systems and Control
- Archaeology and ancient environmental studies
- Astronomical Observations and Instrumentation
- High-pressure geophysics and materials
- Galaxies: Formation, Evolution, Phenomena
- Neutrino Physics Research
- Latin American history and culture
- Maritime and Coastal Archaeology
- Advanced Thermodynamics and Statistical Mechanics
- Nuclear Physics and Applications
Lawrence Livermore National Laboratory
2010-2023
Bates College
2012-2023
Cardiff University
2016-2023
Northeastern University
2022
CEA DAM Île-de-France
2017
Massachusetts Institute of Technology
2017
University of Rochester
2017
Energetics (United States)
2017
Indiana University Bloomington
2017
Ohio University
2017
Abstract: In a time of increasing urbanization, the fundamental value conserving urban biodiversity remains controversial. How much fixed budget should be spent on conservation in versus nonurban landscapes? The answer depend goals that drive our actions, yet proponents often fail to specify motivation for protecting biodiversity. This is an important shortcoming several fronts, including missed opportunity make stronger appeal those who believe biology focus exclusively more natural, wilder...
view Abstract Citations (362) References (32) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The formation and early dynamical evolution of bound stellar systems. Lada, C. J. ; Margulis, M. Dearborn, D. authors present the results numerical N-body calculations which simulate young clusters as they emerge from molecular clouds. They follow initially virialized systems 50 and, in some cases, 100 stars point time immediately after have formed a cloud until long...
Determination of population productivity Neotropical migrant birds and assessment breeding habitat quality have been based on densities nesting success. Data juvenile survival improve our estimates productivity, provide information factors during the post-fledging period that affect this and, with comparative data, enable us to better assess quality. We present first estimate in a birds. studied Wood Thrush ( Hylocichla mustelina) southern Missouri, (U.S.) an area hypothesized contain source...
Low-mass stars, ~1-2 solar masses, near the Main Sequence are efficient at producing He-3, which they mix into convective envelope on giant branch and should distribute Galaxy by way of loss. This process is so that it difficult to reconcile low observed cosmic abundance He-3 with predictions both stellar Big Bang nucleosynthesis. In this paper we find, modeling a red fully three-dimensional hydrodynamic code full nucleosynthetic network, mixing arises in supposedly stable radiative zone...
The spontaneous breaking of a global symmetry leads to the existence Nambu-Goldstone bosons which, through their coupling electrons and/or photons, can transport energy from cores stars and affect significantly course stellar evolution. We find by following in detail evolution that if couplings photons is too strong, helium never ignites---in contradiction with observational evidence. Our limits restrict axion mass less than 0.01 eV, familon scale...
We consider in detail the effect of emission ``hadronic'' invisible axions (which do not couple to electrons) from interior stars on stellar evolution. To this end we calculate plasma rates for due Primakoff process full range conditions encountered a giant star. Much attention is paid plasma, degeneracy, and screening effects. reconsider solar bound by evolving 1.0 ${M}_{\ensuremath{\bigodot}}$ star age lowering presolar helium abundance so as obtain correct present-day luminosity Sun. The...
Telomeres are highly conserved regions of DNA that protect the ends linear chromosomes. The loss telomeres can signal an irreversible change to a cell's state, including cellular senescence. Senescent cells no longer divide and damage nearby healthy cells, thus potentially placing them at crossroads cancer ageing. While epidemiology, molecular biology well studied, newer field exploring telomere in context ecology evolution is just emerging. With work date focusing on how shortening relates...
We determined the effects of microhabitat, year, weather, time season, stage nesting cycle, and brood parasitism on nest predation from a 7-year dataset field sparrows (Spizella pusilla) indigo buntings (Passerina cyanea) in central Missouri, USA. Year, site, interaction species 2-week interval season were important factors explaining predation. The only microhabitat variable that consistently explained was height: nests over 3 m high almost always fledged. Validation model parameters an...
Models concerning the evolution of avian begging behavior predict that nestlings brood parasites should beg more loudly or frequently than nonparasitic and exaggeration calls in general may be limited by risk nest predation. This study is first to test experimentally for a link between parasitism, nestling vocalizations, Begging at Indigo Bunting (Passerina cyanea) nests parasitized Brown-headed Cowbirds (Molothrus ater) were louder frequent those nonparasitized nests. Predation rates...
Three-dimensional stellar modeling has enabled us to identify a deep-mixing mechanism that must operate in all low-mass giants. This mixing process is not optional, and driven by molecular weight inversion created the 3He(3He,2p)4He reaction. In this paper we characterize behavior of mixing, study its impact on envelope abundances. It only eliminates problem 3He overproduction, reconciling big bang nucleosynthesis with observations, but solves discrepancy between observed calculated CNO...
We use the 3D stellar structure code DJEHUTY to model ingestion of protons into intershell convection zone a 1 solar mass asymptotic giant branch star metallicity Z=10^-4. have run two simulations: low resolution one around 300,000 zones, and high consisting 2,000,000 zones. Both simulations been evolved for about 4 hours time. observe existence fast, downward flowing plumes that are able transport hydrogen close proximity helium burning shell before takes place. The in is richer than 1D by...
We model the core helium flash in a low-mass red giant using Djehuty, fully three-dimensional (3D) code. The 3D structures were generated from converged models obtained during 1D evolutionary calculation of 1$\Msun$ star. Independently which starting point we adopted, found that after some transient relaxation settled down with briskly convecting He-burning shell was not very different what predicted.
Abstract Many parasites show fidelity to a set of hosts in ecological time but not evolutionary and the determinants this pattern are poorly understood. Malarial use vertebrate for asexual stage their life cycle Dipteran sexual stage. Despite potential importance hosts, little is known role determining parasite's access hosts. Here, we an avian malarial system Panama explore whether mosquitoes act as filter that limits range used by particular parasite lineages. We amplified sequenced...
— 453 The Auk, Vol. 127, Number 2, pages 453−459. ISSN 0004-8038, electronic 1938-4254. 2010 by American Ornithologists’ Union. All rights reserved. Please direct all requests for permission to photocopy or reproduce article content through the University of California Press’s Rights and Permissions website, http://www.ucpressjournals. com/reprintInfo.asp. DOI: 10.1525/auk.2009.09090 Daniel Hanley,1,2,3 StepHanie M. Doucet,2 anD DonalD c. Dearborn1
The major histocompatibility complex (MHC) is a polymorphic gene family associated with immune defence, and it can play role in mate choice. Under the genetic compatibility hypothesis, females choose mates that differ genetically from their own MHC genotypes, avoiding inbreeding and/or enhancing immunocompetence of offspring. We tested this hypothesis disassortative mating based on genotypes population great frigatebirds ( Fregata minor ) by sequencing second exon class II B. Extensive...
Abstract We used mark–resight data and amplified fragment length polymorphism (AFLP) markers to assess movements gene flow between Central Pacific breeding colonies of the great frigatebird, Fregata minor . Of 715 adult frigatebirds marked on Tern Island Johnston Atoll, 21.3% were resighted at other frigatebird least 582 km away. Mark–resight indicated regular movement males females Atoll (873 apart), less frequent islands; no birds or seen Christmas Island, but one was in Philippines, 7627...