6,762 research outputs found
Personal space as a function of repression-sensitization, sensation-seeking and the stigmatized characteristics of a target person
The concept of personal space has been an unregarded sociological and psychological dimension. Probably the work of animal ethologists has done more to generate interest in spacing and territoriality than any other group of behavioral investigators. The characteristics of individual space in animals has been studied by Hediger (1950, 1955, 1961). From Hediger \u27s import ant work, research in the area of personal space in humans has evolved
Giant Planet Occurrence in the Stellar Mass-Metallicity Plane
Correlations between stellar properties and the occurrence rate of exoplanets
can be used to inform the target selection of future planet search efforts and
provide valuable clues about the planet formation process. We analyze a sample
of 1194 stars drawn from the California Planet Survey targets to determine the
empirical functional form describing the likelihood of a star harboring a giant
planet as a function of its mass and metallicity. Our stellar sample ranges
from M dwarfs with masses as low as 0.2 Msun to intermediate-mass subgiants
with masses as high as 1.9 Msun. In agreement with previous studies, our sample
exhibits a planet-metallicity correlation at all stellar masses; the fraction
of stars that harbor giant planets scales as f \propto 10^{1.2 [Fe/H]}. We can
rule out a flat metallicity relationship among our evolved stars (at 98%
confidence), which argues that the high metallicities of stars with planets are
not likely due to convective envelope "pollution." Our data also rule out a
constant planet occurrence rate for [Fe/H]< 0, indicating that giant planets
continue to become rarer at sub-Solar metallicities. We also find that planet
occurrence increases with stellar mass (f \propto Mstar), characterized by a
rise from 3.5% around M dwarfs (0.5 Msun) to 14% around A stars (2 Msun), at
Solar metallicity. We argue that the correlation between stellar properties and
giant planet occurrence is strong supporting evidence of the core accretion
model of planet formation.Comment: Fixed minor typos, modified the last paragraph of Section
Newly-Discovered Planets Orbiting HD~5319, HD~11506, HD~75784 and HD~10442 from the N2K Consortium
Initially designed to discover short-period planets, the N2K campaign has
since evolved to discover new worlds at large separations from their host
stars. Detecting such worlds will help determine the giant planet occurrence at
semi-major axes beyond the ice line, where gas giants are thought to mostly
form. Here we report four newly-discovered gas giant planets (with minimum
masses ranging from 0.4 to 2.1 MJup) orbiting stars monitored as part of the
N2K program. Two of these planets orbit stars already known to host planets: HD
5319 and HD 11506. The remaining discoveries reside in previously-unknown
planetary systems: HD 10442 and HD 75784. The refined orbital period of the
inner planet orbiting HD 5319 is 641 days. The newly-discovered outer planet
orbits in 886 days. The large masses combined with the proximity to a 4:3 mean
motion resonance make this system a challenge to explain with current formation
and migration theories. HD 11506 has one confirmed planet, and here we confirm
a second. The outer planet has an orbital period of 1627.5 days, and the
newly-discovered inner planet orbits in 223.6 days. A planet has also been
discovered orbiting HD 75784 with an orbital period of 341.7 days. There is
evidence for a longer period signal; however, several more years of
observations are needed to put tight constraints on the Keplerian parameters
for the outer planet. Lastly, an additional planet has been detected orbiting
HD 10442 with a period of 1043 days.Comment: Accepted for publication in Ap
Towards Vulnerability Discovery Using Staged Program Analysis
Eliminating vulnerabilities from low-level code is vital for securing
software. Static analysis is a promising approach for discovering
vulnerabilities since it can provide developers early feedback on the code they
write. But, it presents multiple challenges not the least of which is
understanding what makes a bug exploitable and conveying this information to
the developer. In this paper, we present the design and implementation of a
practical vulnerability assessment framework, called Melange. Melange performs
data and control flow analysis to diagnose potential security bugs, and outputs
well-formatted bug reports that help developers understand and fix security
bugs. Based on the intuition that real-world vulnerabilities manifest
themselves across multiple parts of a program, Melange performs both local and
global analyses. To scale up to large programs, global analysis is
demand-driven. Our prototype detects multiple vulnerability classes in C and
C++ code including type confusion, and garbage memory reads. We have evaluated
Melange extensively. Our case studies show that Melange scales up to large
codebases such as Chromium, is easy-to-use, and most importantly, capable of
discovering vulnerabilities in real-world code. Our findings indicate that
static analysis is a viable reinforcement to the software testing tool set.Comment: A revised version to appear in the proceedings of the 13th conference
on Detection of Intrusions and Malware & Vulnerability Assessment (DIMVA),
July 201
The Phases and Faces of the Duke Lacrosse Controversy: A Conversation James E. Coleman, Jr.
This panel took place at the 2008 Annual Meeting of the Southeastern Association of Law Schools ( SEALS ) in July 2008 in West Palm Beach, Florid
Nonlocalized modulation of periodic reaction diffusion waves: The Whitham equation
In a companion paper, we established nonlinear stability with detailed
diffusive rates of decay of spectrally stable periodic traveling-wave solutions
of reaction diffusion systems under small perturbations consisting of a
nonlocalized modulation plus a localized perturbation. Here, we determine
time-asymptotic behavior under such perturbations, showing that solutions
consist to leading order of a modulation whose parameter evolution is governed
by an associated Whitham averaged equation
The California-Kepler Survey. IV. Metal-rich Stars Host a Greater Diversity of Planets
Probing the connection between a star's metallicity and the presence and
properties of any associated planets offers an observational link between
conditions during the epoch of planet formation and mature planetary systems.
We explore this connection by analyzing the metallicities of Kepler target
stars and the subset of stars found to host transiting planets. After
correcting for survey incompleteness, we measure planet occurrence: the number
of planets per 100 stars with a given metallicity . Planet occurrence
correlates with metallicity for some, but not all, planet sizes and orbital
periods. For warm super-Earths having days and , planet occurrence is nearly constant over metallicities spanning
0.4 dex to +0.4 dex. We find 20 warm super-Earths per 100 stars, regardless
of metallicity. In contrast, the occurrence of warm sub-Neptunes () doubles over that same metallicity interval, from 20 to 40
planets per 100 stars. We model the distribution of planets as , where characterizes the strength of any metallicity
correlation. This correlation steepens with decreasing orbital period and
increasing planet size. For warm super-Earths ,
while for hot Jupiters . High metallicities in
protoplanetary disks may increase the mass of the largest rocky cores or the
speed at which they are assembled, enhancing the production of planets larger
than 1.7 . The association between high metallicity and short-period
planets may reflect disk density profiles that facilitate the inward migration
of solids or higher rates of planet-planet scattering.Comment: 32 pages, 15 figures, 9 tables, accepted for publication in The
Astronomical Journa
The Dynamical Mass and Three-Dimensional Orbit of HR7672B: A Benchmark Brown Dwarf with High Eccentricity
The companion to the G0V star HR7672 directly imaged by Liu et al. (2002) has
moved measurably along its orbit since the discovery epoch, making it possible
to determine its dynamical properties. Originally targeted with adaptive optics
because it showed a long-term radial velocity acceleration (trend), we have
monitored this star with precise Doppler measurements and have now established
a 24 year time baseline. The radial velocity variations show significant
curvature (change in the acceleration) including an inflection point. We have
also obtained a recent image of HR7672B with NIRC2 at Keck. The astrometry also
shows curvature. In this paper, we use jointly-fitted Doppler and astrometric
models to calculate the three-dimensional orbit and dynamical mass of the
companion. The mass of the host star is determined using a direct radius
measurement from CHARA interferometry in combination with high resolution
spectroscopic modeling. We find that HR7672B has a highly eccentric,
, near edge-on, deg, orbit with
semimajor axis, AU. The mass of the companion is
at the 68.2% confidence level. HR7672B thus resides
near the substellar boundary, just below the hydrogen-fusing limit. These
measurements of the companion mass are independent of its brightness and
spectrum and establish HR7672B as a rare and precious "benchmark" brown dwarf
with a well-determined mass, age, and metallicity essential for testing
theoretical evolutionary models and synthetic spectral models. It is presently
the only directly imaged L,T,Y-dwarf known to produce an RV trend around a
solar-type star.Comment: accepted to Ap
The California-Kepler Survey. III. A Gap in the Radius Distribution of Small Planets
The size of a planet is an observable property directly connected to the
physics of its formation and evolution. We used precise radius measurements
from the California-Kepler Survey (CKS) to study the size distribution of 2025
planets in fine detail. We detect a factor of 2 deficit
in the occurrence rate distribution at 1.5-2.0 R. This gap splits
the population of close-in ( < 100 d) small planets into two size regimes:
R < 1.5 R and R = 2.0-3.0 R, with few planets in
between. Planets in these two regimes have nearly the same intrinsic frequency
based on occurrence measurements that account for planet detection
efficiencies. The paucity of planets between 1.5 and 2.0 R supports
the emerging picture that close-in planets smaller than Neptune are composed of
rocky cores measuring 1.5 R or smaller with varying amounts of
low-density gas that determine their total sizes.Comment: Paper III in the California-Kepler Survey series, accepted to the
Astronomical Journa
The Cultural and Commercial Value of Tulsi (Ocimum tenuiflorum L.): Multidisciplinary Approaches Focusing on Species Authentication
Tulsi (Holy basil, Ocimum tenuiflorum L., Lamiaceae), native to Asia, has become globalised as the cultural, cosmetic, and medicinal uses of the herb have been popularised. DNA barcoding, a molecular technique used to identify species based on short regions of DNA, can discriminate between different species and identify contaminants and adulterants. This study aimed to explore the values associated with Tulsi in the United Kingdom (UK) and authenticate samples using DNA barcoding. A mixed methods approach was used, incorporating social research (i.e., structured interviews) and DNA barcoding of Ocimum samples using the ITS and trnH-psbA barcode regions. Interviews revealed the cultural significance of Tulsi: including origins, knowledge exchange, religious connotations, and medicinal uses. With migration, sharing of plants and seeds has been seen as Tulsi plants are widely grown in South Asian (SA) households across the UK. Vouchered Ocimum specimens (n = 33) were obtained to create reference DNA barcodes which were not available in databases. A potential species substitution of O. gratissimum instead of O. tenuiflorum amongst SA participants was uncovered. Commercial samples (n = 47) were difficult to authenticate, potentially due to DNA degradation during manufacturing processes. This study highlights the cultural significance of Tulsi, despite a potential species substitution, the plant holds a prestigious place amongst SA families in the UK. DNA barcoding was a reliable way to authenticate Ocimum species
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