7,829 research outputs found
WASP-1: A lithium- and metal-rich star with an oversized planet
In this paper we present our results of a comprehensive spectroscopicanalysis
of WASP-1, the host star to the exoplanet WASP-1b. We derive T_eff = 6110 +/-
45 K, log g = 4.28 +/- 0.15, and [M/H] = 0.23 +/- 0.08, and also a high
abundance of lithium, log n(Li) = 2.91 +/- 0.05. These parameters suggests an
age for the system of 1-3 Gyr and a stellar mass of 1.25-1.35 M_sun. This means
that WASP-1 has properties very similar to those of HD 149026, the host star
for the highest density planet yet detected. Moreover, their planets orbit at
comparable distances and receive comparable irradiating fluxes from their host
stars. However, despite the similarity of WASP-1 with HD 149026, their planets
have strongly different densities. This suggests that gas-giant planet density
is not a simple function of host-star metallicity or of radiation environment
at ages of ~2 Gyr.Comment: Accepted for publication in MNRAS. 6 pages, 4 figure
Histological and Gross Studies of Brain Tissue of Kittens Exhibiting Spastic Behavior
Histological and gross studies of brain tissue revealed lowered brain weight, lower brain weight to body weight ratios, and poor brain development in relation to the degree of spasticity exhibited in kittens but did not reveal any definite histological changes
Buying Design, Where are we now? Associate Parliamentary Design Innovation Group Term Paper
‘Design ...The purposeful move from a current situation to a preferred situation.’ – Herbert Simon
In 2010 the Associate Parliamentary Design and Innovation Group (APDIG) published a report critiquing government procurement practice as it related to design services. The main accusation was that government too often tried to buy design as though it were a discrete commodity, rather than a creative service, and that this seriously hampered the ultimate outcome for both buyer and supplier. This paper brings an update on the state of design procurement, including the results of an industry consultation conducted by our partners on the initial report, the Design Business Association
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Phonetic Imitation from an Individual-Difference Perspective: Subjective Attitude, Personality and “Autistic” Traits
Numerous studies have documented the phenomenon of phonetic imitation: the process by which the production patterns of an individual become more similar on some phonetic or acoustic dimension to those of her interlocutor. Though social factors have been suggested as a motivator for imitation, few studies has established a tight connection between language-external factors and a speaker’s likelihood to imitate. The present study investigated the phenomenon of phonetic imitation using a within-subject design embedded in an individual-differences framework. Participants were administered a phonetic imitation task, which included two speech production tasks separated by a perceptual learning task, and a battery of measures assessing traits associated with Autism-Spectrum Condition, working memory, and personality. To examine the effects of subjective attitude on phonetic imitation, participants were randomly assigned to four experimental conditions, where the perceived sexual orientation of the narrator (homosexual vs. heterosexual) and the outcome (positive vs. negative) of the story depicted in the exposure materials differed. The extent of phonetic imitation by an individual is significantly modulated by the story outcome, as well as by the participant’s subjective attitude toward the model talker, the participant’s personality trait of openness and the autistic-like trait associated with attention switching.</p
Physiologic and therapeutic roles of somatotropin effects in adult animals
12/94.Includes bibliographical references (pages 11-12)
Seismic velocity structure of seaward-dipping reflectors on the South American continental margin
Seaward dipping reflectors (SDRs) are a key feature within the continent to ocean transition zone of volcanic passive margins. Here we conduct an automated pre-stack depth-migration imaging analysis of commercial seismic data from the volcanic margins of South America. The method used an isotropic, ray-based approach of iterative velocity model building based on the travel time inversion of residual pre-stack depth migration move-out. We find two distinct seismic velocity patterns within the SDRs. While both types show a general increase in velocity with depth consistent with expected compaction and alteration/metamorphic trends, those SDRs that lie within faulted half grabens also have high velocity zones at their down-dip ends. The velocity anomalies are generally concordant with the reflectivity and so we attribute them to the presence of dolerite sills that were injected into the lava pile. The sills therefore result from late-stage melt delivery along the large landward-dipping faults that bound them. In contrast the more outboard SDRs show no velocity anomalies, are more uniform spatially and have unfaulted basal contacts. Our observations imply that the SDRs document a major change in rift architecture, with magmatism linked with early extension and faulting of the upper brittle crust transitioning into more organised, dike-fed eruptions similar to seafloor spreading
A framework for defining seagrass habitat for the Great Barrier Reef, Australia
This report describes a framework to define seagrass habitat and seagrass desired state for the Great Barrier Reef (GBR). We developed this by defining assessment zones using key physical attributes for the GBR. The assessment zones were developed with two main objectives: (1) to assess the representativeness of existing seagrass data throughout the GBR; and (2) to provide a framework in which to develop seagrass desired state (i.e. condition targets).
We defined assessment zones using spatial data that reflect environmental and benthic condition likely to affect seagrass distribution, diversity and density. These include: (1) latitude, defined as regions using 6 Natural Resource Management (NRM) boundaries, (2) influence from and proximity to land (estuarine, coastal, reef, and offshore water bodies), and (3) water depth (intertidal, shallow subtidal 10m) resulting in 68 zones for the GBR. The largest assessment zone was the offshore water body in every region. Deep subtidal was the largest depth zone in coastal, reef, and offshore waters in each region. The estuarine deep subtidal zone was limited. Zones are seagrass-centric and not analogous to the Great Barrier Reef Marine Park zoning.
Data from extensive seagrass surveys and long-term monitoring across the GBR since the early 1980s provides information on seagrass presence/absence, species composition, abundance, and spatial extent. Data rich areas include coastal and estuarine intertidal and shallow subtidal zones. Data from reef and offshore zones, and in deep subtidal zones, are more limited as it comes from sporadic one-off surveys and few meadows have been mapped.
Available seagrass data ranges from sporadic large-scale survey data with low to medium spatial and low temporal resolution, to high spatial and high temporal resolution data collected seasonally at discrete sites.
Defining these assessment zones is a critical first step in defining habitat types and quantifying desired state for GBR seagrasses. Habitat attributes not included in the zones, such as sediment type and exposure to wind and waves, as well as new seagrass biomass data will be used to update the framework, turning it into a full habitat assessment for defining desired state. A case study based in Cleveland Bay, as well as previous research, will be used to identify how this framework will be updated. Seagrass desired state is an ecological target that can be used to assess the effectiveness of management strategies to protect seagrass of the GBR. Desired state analysis requires data with medium to high spatial and temporal resolution that allows assessment in the context of disturbance events, recovery trajectories, and seasonal fluctuations. Robust analysis will be restricted to locations within zones where continuous data collection has occurred, e.g. the Marine Monitoring Program (MMP) and Queensland Ports Seagrass Monitoring Program (QPSMP), and for an adequate time span (generally >10 years)
The first WASP public data release
The WASP (wide angle search for planets) project is an exoplanet transit survey that has been automatically taking wide field images since 2004. Two instruments, one in La Palma and the other in South Africa, continually monitor the night sky, building up light curves of millions of unique objects. These light curves are used to search for the characteristics of exoplanetary transits. This first public data release (DR1) of the WASP archive makes available all the light curve data and images from 2004 up to 2008 in both the Northern and Southern hemispheres. A web interface () to the data allows easy access over the Internet. The data set contains 3 631 972 raw images and 17 970 937 light curves. In total the light curves have 119 930 299 362 data points available between them
The first magnetic maps of a pre-main sequence binary star system - HD 155555
We present the first maps of the surface magnetic fields of a pre-main
sequence binary system. Spectropolarimetric observations of the young, 18 Myr,
HD 155555 (V824 Ara, G5IV + K0IV) system were obtained at the Anglo-Australian
Telescope in 2004 and 2007. Both datasets are analysed using a new binary
Zeeman Doppler imaging (ZDI) code. This allows us to simultaneously model the
contribution of each component to the observed circularly polarised spectra.
Stellar brightness maps are also produced for HD 155555 and compared to
previous Doppler images. Our radial magnetic maps reveal a complex surface
magnetic topology with mixed polarities at all latitudes. We find rings of
azimuthal field on both stars, most of which are found to be non-axisymmetric
with the stellar rotational axis. We also examine the field strength and the
relative fraction of magnetic energy stored in the radial and azimuthal field
components at both epochs. A marked weakening of the field strength of the
secondary star is observed between the 2004 and 2007 epochs. This is
accompanied by an apparent shift in the location of magnetic energy from the
azimuthal to radial field. We suggest that this could be indicative of a
magnetic activity cycle. We use the radial magnetic maps to extrapolate the
coronal field (by assuming a potential field) for each star individually - at
present ignoring any possible interaction. The secondary star is found to
exhibit an extreme tilt (~75 deg) of its large scale magnetic field to that of
its rotation axis for both epochs. The field complexity that is apparent in the
surface maps persists out to a significant fraction of the binary separation.
Any interaction between the fields of the two stars is therefore likely to be
complex also. Modelling this would require a full binary field extrapolation.Comment: 17 pages, 12 figures, accepted for publication in MNRA
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