364 research outputs found
Communicating Phylogeny: Evolutionary Tree Diagrams in Museums
Tree of life diagrams are graphic representations of phylogeny—the evolutionary history and
relationships of lineages—and as such these graphics have the potential to convey key evolutionary
ideas and principles to a variety of audiences. Museums play a significant role in teaching about
evolution to the public, and tree graphics form a common element in many exhibits even though
little is known about their impact on visitor understanding. How phylogenies are depicted and used
in informal science settings impacts their accessibility and effectiveness in communicating about
evolution to visitors. In this paper, we summarize the analysis of 185 tree of life graphics collected
from museum exhibits at 52 institutions and highlight some potential implications of how trees are
presented that may support or hinder visitors’ understanding about evolution. While further work is
needed, existing learning research suggests that common elements among the diversity of museum
trees such as the inclusion of anagenesis and absence of time and shared characters might
represent potential barriers to visitor understanding
Searching for gravitational waves from known pulsars
We present upper limits on the amplitude of gravitational waves from 28
isolated pulsars using data from the second science run of LIGO. The results
are also expressed as a constraint on the pulsars' equatorial ellipticities. We
discuss a new way of presenting such ellipticity upper limits that takes
account of the uncertainties of the pulsar moment of inertia. We also extend
our previous method to search for known pulsars in binary systems, of which
there are about 80 in the sensitive frequency range of LIGO and GEO 600.Comment: Accepted by CQG for the proceeding of GWDAW9, 7 pages, 2 figure
A Joint Search for Gravitational Wave Bursts with AURIGA and LIGO
The first simultaneous operation of the AURIGA detector and the LIGO
observatory was an opportunity to explore real data, joint analysis methods
between two very different types of gravitational wave detectors: resonant bars
and interferometers. This paper describes a coincident gravitational wave burst
search, where data from the LIGO interferometers are cross-correlated at the
time of AURIGA candidate events to identify coherent transients. The analysis
pipeline is tuned with two thresholds, on the signal-to-noise ratio of AURIGA
candidate events and on the significance of the cross-correlation test in LIGO.
The false alarm rate is estimated by introducing time shifts between data sets
and the network detection efficiency is measured with simulated signals with
power in the narrower AURIGA band. In the absence of a detection, we discuss
how to set an upper limit on the rate of gravitational waves and to interpret
it according to different source models. Due to the short amount of analyzed
data and to the high rate of non-Gaussian transients in the detectors noise at
the time, the relevance of this study is methodological: this was the first
joint search for gravitational wave bursts among detectors with such different
spectral sensitivity and the first opportunity for the resonant and
interferometric communities to unify languages and techniques in the pursuit of
their common goal.Comment: 18 pages, IOP, 12 EPS figure
Search for gravitational waves from binary inspirals in S3 and S4 LIGO data
We report on a search for gravitational waves from the coalescence of compact
binaries during the third and fourth LIGO science runs. The search focused on
gravitational waves generated during the inspiral phase of the binary
evolution. In our analysis, we considered three categories of compact binary
systems, ordered by mass: (i) primordial black hole binaries with masses in the
range 0.35 M(sun) < m1, m2 < 1.0 M(sun), (ii) binary neutron stars with masses
in the range 1.0 M(sun) < m1, m2 < 3.0 M(sun), and (iii) binary black holes
with masses in the range 3.0 M(sun)< m1, m2 < m_(max) with the additional
constraint m1+ m2 < m_(max), where m_(max) was set to 40.0 M(sun) and 80.0
M(sun) in the third and fourth science runs, respectively. Although the
detectors could probe to distances as far as tens of Mpc, no gravitational-wave
signals were identified in the 1364 hours of data we analyzed. Assuming a
binary population with a Gaussian distribution around 0.75-0.75 M(sun), 1.4-1.4
M(sun), and 5.0-5.0 M(sun), we derived 90%-confidence upper limit rates of 4.9
yr^(-1) L10^(-1) for primordial black hole binaries, 1.2 yr^(-1) L10^(-1) for
binary neutron stars, and 0.5 yr^(-1) L10^(-1) for stellar mass binary black
holes, where L10 is 10^(10) times the blue light luminosity of the Sun.Comment: 12 pages, 11 figure
How the Rural Risk Environment Underpins Hepatitis C Risk: Qualitative Findings From Rural Southern Illinois, United States
Background: Hepatitis C virus (HCV) infection has increased among persons who inject drugs (PWID) in the United States with disproportionate burden in rural areas. We use the Risk Environment framework to explore potential economic, physical, social, and political determinants of hepatitis C in rural southern Illinois.
Methods: Nineteen in-depth semi-structured interviews were conducted with PWID from August 2019 through February 2020 (i.e., pre-COVID-19 pandemic) and four with key informants who professionally worked with PWID. Interviews were recorded, professionally transcribed, and coded using qualitative software. We followed a grounded theory approach for coding and analyses.
Results: We identify economic, physical, policy, and social factors that may influence HCV transmission risk and serve as barriers to HCV care. Economic instability and lack of economic opportunities, a lack of physically available HCV prevention and treatment services, structural stigma such as policies that criminalize drug use, and social stigma emerged in interviews as potential risks for transmission and barriers to care.
Conclusion: The rural risk environment framework acknowledges the importance of community and structural factors that influence HCV infection and other disease transmission and care. We find that larger structural factors produce vulnerabilities and reduce access to resources, which negatively impact hepatitis C disease outcomes
Search for Gravitational Waves Associated with 39 Gamma-Ray Bursts Using Data from the Second, Third, and Fourth LIGO Runs
We present the results of a search for short-duration gravitational-wave
bursts associated with 39 gamma-ray bursts (GRBs) detected by gamma-ray
satellite experiments during LIGO's S2, S3, and S4 science runs. The search
involves calculating the crosscorrelation between two interferometer data
streams surrounding the GRB trigger time. We search for associated
gravitational radiation from single GRBs, and also apply statistical tests to
search for a gravitational-wave signature associated with the whole sample. For
the sample examined, we find no evidence for the association of gravitational
radiation with GRBs, either on a single-GRB basis or on a statistical basis.
Simulating gravitational-wave bursts with sine-gaussian waveforms, we set upper
limits on the root-sum-square of the gravitational-wave strain amplitude of
such waveforms at the times of the GRB triggers. We also demonstrate how a
sample of several GRBs can be used collectively to set constraints on
population models. The small number of GRBs and the significant change in
sensitivity of the detectors over the three runs, however, limits the
usefulness of a population study for the S2, S3, and S4 runs. Finally, we
discuss prospects for the search sensitivity for the ongoing S5 run, and beyond
for the next generation of detectors.Comment: 24 pages, 10 figures, 14 tables; minor changes to text and Fig. 2;
accepted by Phys. Rev.
An expanded phase I/II trial of cyclophosphamide, etoposide, and carboplatin plus total body irradiation with autologous marrow or stem cell support for patients with hematologic malignancies
AbstractThe major cause for failure of autologous stem cell transplantation for hematologic malignancies is the risk of recurrent disease. As a result, new treatment regimens that include novel agents or combinations of agents and approaches are needed. The current report describes a large Phase I/II, single-center trial that includes 60 patients with a variety of hematologic malignancies. These patients received a fixed dose of carboplatin (1 g/m2/d × 72 hours by CI) etoposide (600 mg/m2/d × 3 days) and cyclophosphamide (2 g/m2/d × 3 days), plus escalating doses of total body irradiation (TBI) (at 1000, 1200, and 1295 cGy) over 3 days. Eleven patients received infusion of autologous marrow, 32 received peripheral blood stem cells, and 17 patients received both. The maximum tolerated dose of this regimen was a radiation dose of 1200 cGy given in 200-cGy fractions BID × 3 days. The dose-limiting toxicity was mucositis, with 97% of patients requiring narcotic analgesia for mouth pain. Overall treatment-related mortality was 6.7%, with 2 of the 4 deaths occurring in a group of 9 patients aged 60 and older. Responses were seen in all patient groups, but the most encouraging outcomes were seen in 12 patients with high-risk or advanced acute myelocytic lymphoma (AML), 7 of whom remain alive and free of disease beyond 5 years. This regimen is intensive and causes considerable mucositis but is otherwise well tolerated and has demonstrated activity in a number of hematologic malignancies, especially AML
Search for Gravitational Waves from Primordial Black Hole Binary Coalescences in the Galactic Halo
We use data from the second science run of the LIGO gravitational-wave
detectors to search for the gravitational waves from primordial black hole
(PBH) binary coalescence with component masses in the range 0.2--.
The analysis requires a signal to be found in the data from both LIGO
observatories, according to a set of coincidence criteria. No inspiral signals
were found. Assuming a spherical halo with core radius 5 kpc extending to 50
kpc containing non-spinning black holes with masses in the range 0.2--, we place an observational upper limit on the rate of PBH coalescence
of 63 per year per Milky Way halo (MWH) with 90% confidence.Comment: 7 pages, 4 figures, to be submitted to Phys. Rev.
Search for gravitational wave bursts in LIGO's third science run
We report on a search for gravitational wave bursts in data from the three
LIGO interferometric detectors during their third science run. The search
targets subsecond bursts in the frequency range 100-1100 Hz for which no
waveform model is assumed, and has a sensitivity in terms of the
root-sum-square (rss) strain amplitude of hrss ~ 10^{-20} / sqrt(Hz). No
gravitational wave signals were detected in the 8 days of analyzed data.Comment: 12 pages, 6 figures. Amaldi-6 conference proceedings to be published
in Classical and Quantum Gravit
I Don\u27t Believe a Person Has to Die When Trying to Get High: Overdose Prevention and Response Strategies in Rural Illinois
BACKGROUND: Overdose is a leading cause of morbidity and mortality among people who inject drugs. Illicitly manufactured fentanyl is now a major driver of opioid overdose deaths.
METHODS: Semi-structured interviews were conducted with 23 participants (19 persons who inject drugs and 4 service providers) from rural southern Illinois. Data were analyzed using constant comparison and theoretical sampling methods.
RESULTS: Participants were concerned about the growing presence of fentanyl in both opioids and stimulants, and many disclosed overdose experiences. Strategies participants reported using to lower overdose risk included purchasing drugs from trusted sellers and modifying drug use practices by partially injecting and/or changing the route of transmission. Approximately half of persons who inject drugs sampled had heard of fentanyl test strips, however fentanyl test strip use was low. To reverse overdoses, participants reported using cold water baths. Use of naloxone to reverse overdose was low. Barriers to naloxone access and use included fear of arrest and opioid withdrawal.
CONCLUSIONS: People who inject drugs understood fentanyl to be a potential contaminant in their drug supply and actively engaged in harm reduction techniques to try to prevent overdose. Interventions to increase harm reduction education and information about and access to fentanyl test strips and naloxone would be beneficial
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