515 research outputs found
Laser Guide Star Adaptive Optics Integral Field Spectroscopy of a Tightly Collimated Bipolar Jet from the Herbig Ae star LkHa 233
We have used the integral field spectrograph OSIRIS and laser guide star
adaptive optics at Keck Observatory to obtain high angular resolution (0.06"),
moderate spectral resolution (R ~ 3800) images of the bipolar jet from the
Herbig Ae star LkHa 233, seen in near-IR [Fe II] emission at 1.600 & 1.644
microns. This jet is narrow and tightly collimated, with an opening angle of
only 9 degrees, and has an average radial velocity of ~ 100 km/s. The jet and
counterjet are asymmetric, with the red-shifted jet much clumpier than its
counterpart at the angular resolution of our observations. The observed
properties are in general similar to jets seen around T Tauri stars, though it
has a relatively large mass flux of (1.2e-7 +- 0.3e-7) M_sun/year, near the
high end of the observed mass flux range around T Tauri stars. We also
spatially resolve an inclined circumstellar disk around LkHa 233, which
obscures the star from direct view. By comparison with numerical radiative
transfer disk models, we estimate the disk midplane to be inclined i = 65 +- 5
degrees relative to the plane of the sky. Since the star is seen only in
scattered light at near-infrared wavelengths, we detect only a small fraction
of its intrinsic flux. Because previous estimates of its stellar properties did
not account for this, either LkHa 233 must be located closer than the
previously believed, or its true luminosity must be greater than previously
supposed, consistent with its being a ~4 M_sun star near the stellar birthline.Comment: Accepted for publication in the Ap
The Molecular Gas Environment around Two Herbig Ae/Be Stars: Resolving the Outflows of LkHa 198 and LkHa 225S
Observations of outflows associated with pre-main-sequence stars reveal
details about morphology, binarity and evolutionary states of young stellar
objects. We present molecular line data from the Berkeley-Illinois-Maryland
Association array and Five Colleges Radio Astronomical Observatory toward the
regions containing the Herbig Ae/Be stars LkHa 198 and LkHa 225S. Single dish
observations of 12CO 1-0, 13CO 1-0, N2H+ 1-0 and CS 2-1 were made over a field
of 4.3' x 4.3' for each species. 12CO data from FCRAO were combined with high
resolution BIMA array data to achieve a naturally-weighted synthesized beam of
6.75'' x 5.5'' toward LkHa 198 and 5.7'' x 3.95'' toward LkHa 225S,
representing resolution improvements of factors of approximately 10 and 5 over
existing data. By using uniform weighting, we achieved another factor of two
improvement. The outflow around LkHa 198 resolves into at least four outflows,
none of which are centered on LkHa 198-IR, but even at our resolution, we
cannot exclude the possibility of an outflow associated with this source. In
the LkHa 225S region, we find evidence for two outflows associated with LkHa
225S itself and a third outflow is likely driven by this source. Identification
of the driving sources is still resolution-limited and is also complicated by
the presence of three clouds along the line of sight toward the Cygnus
molecular cloud. 13CO is present in the environments of both stars along with
cold, dense gas as traced by CS and (in LkHa 225S) N2H+. No 2.6 mm continuum is
detected in either region in relatively shallow maps compared to existing
continuum observations.Comment: 14 pages, 10 figures (5 color), accepted for publication in Ap
Identification and molecular genetic analysis of the cichorine gene cluster in Aspergillus nidulans
We recently demonstrated that the phytotoxin cichorine is produced by Aspergillus nidulans. Through a set of targeted deletions, we have found a cluster of seven genes that are required for its biosynthesis. Two of the deletions yielded molecules that give information about the biosynthesis of this metabolite
EFBAT: exact family-based association tests
Background: Family-based association tests are important tools for investigating genetic risk factors of complex diseases. These tests are especially valuable for being robust to population structure. We introduce a tool, EFBAT, which performs exact family-based tests of association for X-chromosome and autosomal biallelic markers. Results: The program EFBAT extends a network algorithm previously applied to autosomal markers to include the X-chromosome and to perform tests of association under the null hypotheses "no association, no linkage" and "no association in the presence of linkage" under additive, dominant and recessive genetic models. These tests are valid regardless of patterns of missing familial data. Conclusion: The general framework for performing exact family-based association tests has been usefully extended to the X-chromosome, particularly for the hypothesis of "no association in the presence of linkage" and for different genetic models
The effects of changes in the order of verbal labels and numerical values on children's scores on attitude and rating scales
Research with adults has shown that variations in verbal labels and numerical scale values on rating scales can affect the responses given. However, few studies have been conducted with children. The study aimed to examine potential differences in childrenâs responses to Likert-type rating scales according to their anchor points and scale direction, and to see whether or not such differences were stable over time. 130 British children, aged 9 to 11, completed six sets of Likert-type rating scales, presented in four different ways varying the position of positive labels and numerical values. The results showed, both initially and 8-12 weeks later, that presenting a positive label or a high score on the left of a scale led to significantly higher mean scores than did the other variations. These findings indicate that different arrangements of rating scales can produce different results which has clear implications for the administration of scales with children
Hate crimes against trans people: assessing emotions, behaviors and attitudes towards criminal justice agencies
Based on a survey of 593 lesbian, gay, bisexual, and transgender (LGBT) people in the United Kingdom, this study shows that direct anti-LGBT hate crimes (measured by direct experiences of victimization) and indirect anti-LGBT hate crimes (measured by personally knowing other victims of hate crime) are highly prolific and frequent experiences for LGBT people. Our findings show that trans people are particularly susceptible to hate crimes, both in terms of prevalence and frequency. This article additionally highlights the negative emotional and (intended) behavioral reactions that were correlated with an imagined hate crime scenario, showing that trans people are more likely to experience heightened levels of threat, vulnerability, and anxiety compared with non-trans LGB people. The study found that trans people are also more likely to feel unsupported by family, friends, and society for being LGBT, which was correlated with the frequency of direct (verbal) abuse they had previously endured. The final part of this study explores trans peopleâs confidence levels in the Government, the police, and the Crown Prosecution Service (CPS) in relation to addressing hate crime. In general, trans people felt that the police are not effective at policing anti-LGBT hate crime, and they are not respectful toward them as victims; this was especially true where individuals had previous contact with the police. Respondents were also less confident in the CPS to prosecute anti-LGBT hate crimes, though the level of confidence was slightly higher when respondents had direct experience with the CPS. The empirical evidence presented here supports the assertion that all LGBT people, but particularly trans individuals, continue to be denied equal participation in society due to individual, social, and structural experiences of prejudice. The article concludes by arguing for a renewed policy focus that must address this issue as a public health problem
Portland\u27s Changing Landscape
Occasional Papers in Geography Publication No. 4
What is the nature and character of Portland? What are the conditions, changes and developments that have made it what it is? How does Portland compare with other places? What makes it unique? These are some of the question pursued in this volume.
This book contains thirteen chapters discussing various facets of Portland\u27s environmental, economy, and character. It is an up-to-date and comprehensive analysis of dynamics and change in the landscape. An overview is provided of Portland as a city and place to live, as well as its functional significance on a national and international basis.
Two threads are woven through the tapestry of these essays. One is that Portland is a big city but with many attributes of a small town. The other is the closeness and accessibility of city and nature. The challenge is how to nurture and maintain both - to have our cake and eat it too. The evidence is clear that most American cities have not been able to achieve this. Only the future can tell how Portland will fare.
The authors are all professional geographers or work in closely related fields. All have been involved with the Portland scene for a number of years and are uniquely qualified to write about these topics. While each approaches problems from his or her own perspective, the net result is a summing up, a taking stock of where we have been and where we are going. When considered as a whole the book should provide a better view than we have had of the nature and character of this special place.https://pdxscholar.library.pdx.edu/geog_occasionalpaper/1000/thumbnail.jp
Kinome rewiring reveals AURKA limits PI3K-pathway inhibitor efficacy in breast cancer.
Dysregulation of the PI3K-AKT-mTOR signaling network is a prominent feature of breast cancers. However, clinical responses to drugs targeting this pathway have been modest, possibly because of dynamic changes in cellular signaling that drive resistance and limit drug efficacy. Using a quantitative chemoproteomics approach, we mapped kinome dynamics in response to inhibitors of this pathway and identified signaling changes that correlate with drug sensitivity. Maintenance of AURKA after drug treatment was associated with resistance in breast cancer models. Incomplete inhibition of AURKA was a common source of therapy failure, and combinations of PI3K, AKT or mTOR inhibitors with the AURKA inhibitor MLN8237 were highly synergistic and durably suppressed mTOR signaling, resulting in apoptosis and tumor regression in vivo. This signaling map identifies survival factors whose presence limits the efficacy of targeted therapies and reveals new drug combinations that may unlock the full potential of PI3K-AKT-mTOR pathway inhibitors in breast cancer
TIC 378898110: A Bright, Short-Period AM CVn Binary in TESS
AM CVn-type systems are ultracompact, helium-accreting binary systems which
are evolutionarily linked to the progenitors of thermonuclear supernovae and
are expected to be strong Galactic sources of gravitational waves detectable to
upcoming space-based interferometers. AM CVn binaries with orbital periods
20--23 min exist in a constant high state with a permanently ionised
accretion disc. We present the discovery of TIC 378898110, a bright (
mag), nearby ( pc), high-state AM CVn binary discovered in TESS
two-minute-cadence photometry. At optical wavelengths this is the
third-brightest AM CVn binary known. The photometry of the system shows a
23.07172(6) min periodicity, which is likely to be the `superhump' period and
implies an orbital period in the range 22--23 min. There is no detectable
spectroscopic variability. The system underwent an unusual, year-long
brightening event during which the dominant photometric period changed to a
shorter period (constrained to min), which we suggest may be
evidence for the onset of disc-edge eclipses. The estimated mass transfer rate,
, is
unusually high and may suggest a high-mass or thermally inflated donor. The
binary is detected as an X-ray source, with a flux of erg cm s in the 0.3--10 keV range. TIC 378898110
is the shortest-period binary system discovered with TESS, and its large
predicted gravitational-wave amplitude makes it a compelling verification
binary for future space-based gravitational wave detectors.Comment: 15 pages, 14 figures. Accepted to MNRA
Urine and Plasma Metabolome of Healthy Adults Consuming the DASH (Dietary Approaches to Stop Hypertension) Diet: A Randomized Pilot Feeding Study
We aimed to identify plasma and urine metabolites altered by the Dietary Approaches to Stop Hypertension (DASH) diet in a post-hoc analysis of a pilot feeding trial. Twenty adult participants with un-medicated hypertension consumed a Control diet for one week followed by 2 weeks of random assignment to either Control or DASH diet. Non-missing fasting plasma (n = 56) and 24-h urine (n = 40) were used to profile metabolites using untargeted gas chromatography/mass spectrometry. Linear models were used to compare metabolite levels between the groups. In urine, 19 identifiable untargeted metabolites differed between groups at p < 0.05. These included a variety of phenolic acids and their microbial metabolites that were higher during the DASH diet, with many at false discovery rate (FDR) adjusted p < 0.2. In plasma, eight identifiable untargeted metabolites were different at p < 0.05, but only gamma-tocopherol was significantly lower on DASH at FDR adjusted p < 0.2. The results provide insights into the mechanisms of benefit of the DASH diet
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