295 research outputs found
Separated Fringe Packet Observations with the CHARA Array II: Andromeda, HD 178911, and {\xi} Cephei
When observed with optical long-baseline interferometers (OLBI), components
of a binary star which are sufficiently separated produce their own
interferometric fringe packets; these are referred to as Separated Fringe
Packet (SFP) binaries. These SFP binaries can overlap in angular separation
with the regime of systems resolvable by speckle interferometry at single,
large-aperture telescopes and can provide additional measurements for
preliminary orbits lacking good phase coverage, help constrain elements of
already established orbits, and locate new binaries in the undersampled regime
between the bounds of spectroscopic surveys and speckle interferometry. In this
process, a visibility calibration star is not needed, and the separated fringe
packets can provide an accurate vector separation. In this paper, we apply the
SFP approach to {\omega} Andromeda, HD 178911, and {\xi} Cephei with the CLIMB
three-beam combiner at the CHARA Array. For these systems we determine
component masses and parallax of 0.9630.049 and
0.8600.051 and 39.541.85 milliarcseconds (mas) for
{\omega} Andromeda, for HD 178911 of 0.8020.055 and
0.6220.053 with 28.261.70 mas, and masses of
1.0450.031 and 0.4080.066 and
38.102.81 mas for {\xi} Cephei.Comment: 28 pages, 4 tables, 6 figures, accepted to AJ May 201
Habitat Characterization, Distribution, and Areal Extent of Deep-sea Coral Ecosystems off Florida, Southeastern U.S.A.
The deep-sea (200-1000 m) seafloor off the southeastern U.S. has a variety of extensive deep-sea coral ecosystem (DSCE) habitats including: deep-water coral mounds; various hard-bottom habitats off Florida including the Miami Terrace, Pourtales Terrace, and deep-water canyons (Agassiz and Tortugas Valleys); and deep island slopes off western Bahamas and northern Cuba. The dominant structure-forming scleractinian corals are Lophelia pertusa and Enallopsammia profunda; other structure-forming taxa include stylasterid corals, gorgonians, black corals, and sponges. This biota is associated with hard-bottom seafloor of variable high-relief topography which can be remotely identified from bathymetric data. NOAA bathymetric contour maps and digital elevation models were used to identify and delineate the areal extent of potential DSCE habitat in the region from northeastern Florida through the Straits of Florida. These were ground-truthed with 241 dives with submersibles and remotely operated vehicles which confirmed deep-sea coral habitat. We estimate a total of 39,910 km2 of DSCE habitat in this region. By comparison, the estimated areal extent of shallow-water coral habitat for all U.S. waters is 36,813 km2. Bottom trawling remains the greatest threat to DSCEs worldwide, and as a result NOAA has established five deep-water Coral Habitat Areas of Particular Concern (CHAPCs), encompassing 62,714 km2 from North Carolina to south Florida, which will protect much of the known deep-sea coral habitat in this region. High-resolution surveys are not only critical to define DSCE habitats but also to define areas devoid of coral and sponge habitats that may allow for potential bottom fisheries and energy development
Movement of \u3ci\u3eHypophthalmichthys\u3c/i\u3e DNA in the Illinois River Watershed by the Double-Crested Cormorant (\u3ci\u3ePhalacrocorax auritus\u3c/i\u3e)
Paired throat and cloacal swabs, along with feather samples, from nesting Double-crested Cormorants (Phalacrocorax auritus) at two sites in Illinois, USA, were tested for presence of invasive bigheaded carp (Hypophthalmichthys spp.) DNA. We also used DNA from the feather calamus to determine cormorant sex. Throat and cloacal swabs from cormorants at both locations tested positive for DNA from silver carp (H. molitrix), but none tested positive for bighead carp (H. nobilis). Hypophthalmichthys DNA was not detected on feathers. There were no significant differences among positive Hypophthalmichthys DNA detection frequencies between cormorant sexes. To our knowledge, this is the first demonstration of silver carp as part of the Double-crested Cormorant diet in North America. Hypophthalmichthys are major invasive species of concern in this region, the detection of water-borne environmental DNA of Hypophthalmichthys is an important monitoring tool, and the potential movement of DNA via piscivorous birds may have significant implications for interpreting environmental DNA monitoring data
Interferometry of Aurigae: Characterization of the asymmetric eclipsing disk
We report on a total of 106 nights of optical interferometric observations of
the Aurigae system taken during the last 14 years by four beam
combiners at three different interferometric facilities. This long sequence of
data provides an ideal assessment of the system prior to, during, and after the
recent 2009-2011 eclipse. We have reconstructed model-independent images from
the 10 in-eclipse epochs which show that a disk-like object is indeed
responsible for the eclipse. Using new 3D, time-dependent modeling software, we
derive the properties of the F-star (diameter, limb darkening), determine
previously unknown orbital elements (, ), and access the global
structures of the optically thick portion of the eclipsing disk using both
geometric models and approximations of astrophysically relevant density
distributions. These models may be useful in future hydrodynamical modeling of
the system. Lastly, we address several outstanding research questions including
mid-eclipse brightening, possible shrinking of the F-type primary, and any
warps or sub-features within the disk.Comment: 105 pages, 57 figures. This is an author-created, un-copyedited
version of an article accepted for publication in Astrophysical Journal
Supplement Series. IOP Publishing Ltd is not responsible for any errors or
omissions in this version of the manuscript or any version derived from i
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The longitudinal association between resting heart rate and psychopathic traits from a normative personality perspective
A large body of research has accumulated investigating the possibility of an association between resting heart rate and psychopathic traits, with meta-analysis suggesting a modest, negative association. Some recent research suggests that prior findings of an association between heart rate and psychopathy may be influenced by inclusion of antisocial behavior in the assessment of psychopathic traits. The current study explores this possibility in a longitudinal sample of British males by comparing resting heart rate at age 18 to psychopathy assessed from a Five Factor Model perspective and from the Psychopathy Checklist: Screening Version (PCL:SV) at age 48. Our psychopathic personality scale, created using the Big Five Inventory (BFI), was significantly correlated with the PCL:SV and was most related to the antisocial factor. In correlation analyses, resting heart rate at age 18 was not significantly related to BFI psychopathy, but was positively related to BFI Openness and Conscientiousness, and these associations held up after controlling for childhood SES, BMI at 18, and whether the participant smoked during the age 18 assessment. Additional analyses controlling for smoking status were conducted to address the biasing effect of smoking on heart rate during the age 18 assessment and a significant, albeit weak, negative association between resting heart rate and BFI psychopathy emerged. Future research should replicate these results using other normative personality approaches to assess psychopathic traits.We are very grateful to the Home Office, the Department of Health, the Department of Education, the Rayne Foundation, the Barrow Cadbury Trust, and the Smith-Richardson Foundation for funding the Cambridge Study in Delinquent Development
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Examining the association between childhood cognitive ability and psychopathic traits at age 48
Despite early theorists suggesting that psychopathic traits are associated with higher intelligence, meta-analytic work has found that global psychopathy scores are actually negatively related to intelligence, albeit weakly. Furthermore, it was reported in the same meta-analytic work that the various dimensions of psychopathy were differentially related to intelligence. Importantly, virtually all of the research to date has relied on cross-sectional associations. The current study examined whether intelligence scores (verbal comprehension, non-verbal IQ, and a global intelligence composite) at age 8 were associated with psychopathy scores at age 48 in a sample of white, urban males from London (analytical n = 292). Results suggested a significant, but weak, inverse association between intelligence and the affective, lifestyle, and antisocial facets of psychopathy and a nonsignificant association with the interpersonal facet, as assessed by the Psychopathy Checklist: Screening Version. These findings contribute to the growing body of evidence suggesting that psychopathy, as conceptualized in most modern models, is either very weakly inversely related to, or simply not a correlate of intelligence.We are very grateful to the Home Office, the Department of Health, the Department of Education, the Rayne Foundation, the Barrow Cadbury Trust, and the Smith Richardson Foundation for funding the Cambridge Study in Delinquent Developmen
In the Shadow of the Transiting Disk: Imaging epsilon Aurigae in Eclipse
Eclipses of the single-line spectroscopic binary star, epsilon Aurigae,
provide an opportunity to study the poorly-defined companion. We used the MIRC
beam combiner on the CHARA array to create interferometric images during
eclipse ingress. Our results demonstrate that the eclipsing body is a dark disk
that is opaque and tilted, and therefore exclude alternative models for the
system. These data constrain the geometry and masses of the components,
providing evidence that the F-star is not a massive supergiant star.Comment: As submitted to Nature. Published in Nature April 8, 2010
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