185 research outputs found
High Resolution Rapid Response observations of compact radio sources with the Ceduna Hobart Interferometer (CHI)
Context. Frequent, simultaneous observations across the electromagnetic
spectrum are essential to the study of a range of astrophysical phenomena
including Active Galactic Nuclei. A key tool of such studies is the ability to
observe an object when it flares i.e. exhibits a rapid and significant increase
in its flux density.
Aims. We describe the specific observational procedures and the calibration
techniques that have been developed and tested to create a single baseline
radio interferometer that can rapidly observe a flaring object. This is the
only facility that is dedicated to rapid high resolution radio observations of
an object south of -30 degrees declination. An immediate application is to
provide rapid contemporaneous radio coverage of AGN flaring at {\gamma}-ray
frequencies detected by the Fermi Gamma-ray Space Telescope.
Methods. A single baseline interferometer was formed with radio telescopes in
Hobart, Tasmania and Ceduna, South Australia. A software correlator was set up
at the University of Tasmania to correlate these data.
Results. Measurements of the flux densities of flaring objects can be made
using our observing strategy within half an hour of a triggering event. These
observations can be calibrated with amplitude errors better than 15%. Lower
limits to the brightness temperatures of the sources can also be calculated
using CHI.Comment: 6 pages, 6 figures, 1 table. Accepted for publication in A&
Stakeholders\u27 Perceptions of a Hospital Based Emergency Medicine Education & Training Program: A System Change
Background: Emergency Medicine (EM) is a new and developing specialty around the world. In India, one model for capacity building has been the development of partnerships between US academic institutions and private healthcare institutions for implementing post-graduate education and training in EM. Initiated in 2007, programs have grown both in number and scope and have continued to attract new students and partner institutions. This study was undertaken to better understand the impact of EM training programs on hospital systems.
Methods: A mixed-methods evaluation was undertaken at 5 program sites across India in the summer of 2016. Two researchers conducted onsite semi-structured interviews with key program stakeholders. Participants included hospital administrators, program directors, hospital consultants, and ancillary staff at each hospital. Interviews were recorded, transcribed and then analyzed using a rapid assessment process. Participants also completed a brief survey. Written surveys were analyzed with univariate analysis.
Results: A total of 109 stakeholders were interviewed. Positive impacts were reported among all stakeholders, particularly among administrators, consultants, ancillary staff, and supervising physicians in the ED. 80% of hospital administrators and 90% of direct ED supervisors report improved quality of care particularly among critically ill patients. Some respondents, including 89% of administrators, attributed increased patient volumes at least in part due to the educational program. Of respondents, non-ED consultants were less likely to report improvement in quality during off-service rotations, but 92% reported improved patient care in the hospital related to the program. Positive impacts extended beyond the hospital with many examples of community outreach, layperson education, and improved hospital reputation.
Discussion: Evaluation of a changing system of emergency care has proven challenging to study. These data reflect substantial impacts to a hospital and the surrounding system after development of an EM training program, extending beyond the hospital itself to community outreach programs and a wide variety of education and training programs. Further investigation may prove helpful in quantifying the reported improvement in quality and scope of impact
Multi-epoch VLBI of a double maser super burst
In a rare and spectacular display, two well-known massive star forming
regions, W49N and G25.65+1.05, recently underwent maser 'super burst' - their
fluxes suddenly increasing above 30,000 and 18,000 Jy, respectively, reaching
several orders of magnitude above their usual values. In quick-response, ToO
observations with the EVN, VLBA and KaVA were obtained constituting a 4 week
campaign - producing a high-cadence multi-epoch VLBI investigation of the maser
emission. The combination of high-resolution, polarisation and flux monitoring
during the burst provides one of the best accounts, to date, of the maser super
burst phenomenon, aiding their use as astrophysical tools. These proceedings
contain the preliminary results of our campaign
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Gemfibrozil Inhibits Legionella pneumophila and Mycobacterium tuberculosis Enoyl Coenzyme A Reductases and Blocks Intracellular Growth of These Bacteria in Macrophages
We report here that gemfibrozil (GFZ) inhibits axenic and intracellular growth of Legionella pneumophila and of 27 strains of wild-type and multidrug-resistant Mycobacterium tuberculosis in bacteriological medium and in human and mouse macrophages, respectively. At a concentration of 0.4 mM, GFZ completely inhibited L. pneumophila fatty acid synthesis, while at 0.12 mM it promoted cytoplasmic accumulation of polyhydroxybutyrate. To assess the mechanism(s) of these effects, we cloned an L. pneumophila FabI enoyl reductase homolog that complemented for growth an Escherichia coli strain carrying a temperature-sensitive enoyl reductase and rendered the complemented E. coli strain sensitive to GFZ at the nonpermissive temperature. GFZ noncompetitively inhibited this L. pneumophila FabI homolog, as well as M. tuberculosis InhA and E. coli FabI
The First VLBI Detection of a Spiral DRAGN Core
The existence of spiral DRAGNs challenges standard galaxy formation theories.
We present the first observation of 0313192, the archetypal spiral DRAGN, at
VLBI resolutions. Spiral DRAGNs are Double Radio Sources Associated with
Galactic Nuclei (DRAGNs) that are hosted by spiral galaxies. 0313192 is an
edge-on spiral galaxy that appears to host a 360 kpc double-lobed radio source.
The core of this galaxy is clearly detected at L, S, and X-bands using the
VLBA, signifying an ongoing active nucleus in the galaxy. This rules out the
possibility that the spiral DRAGN is merely a chance alignment. The radio core
has LW Hz. Radio components are
detected to the South-West of the core, but there are no detections of a
counterjet. Assuming a symmetric, relativistic jet, we estimate an upper limit
to the inclination angle of degrees. The VLBI-detected
radio jet components are extremely well-aligned with the larger-scale radio
source suggesting little to no jet disruption or interaction with the ISM of
the host galaxy.Comment: 6 pages, 4 figure
Unexpected role for IL-17 in protective immunity against hypervirulent Mycobacterium tuberculosis HN878 infection
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), infects one third of the world's population. Among these infections, clinical isolates belonging to the W-Beijing appear to be emerging, representing about 50% of Mtb isolates in East Asia, and about 13% of all Mtb isolates worldwide. In animal models, infection with W-Beijing strain, Mtb HN878, is considered "hypervirulent" as it results in increased mortality and causes exacerbated immunopathology in infected animals. We had previously shown the Interleukin (IL) -17 pathway is dispensable for primary immunity against infection with the lab adapted Mtb H37Rv strain. However, it is not known whether IL-17 has any role to play in protective immunity against infection with clinical Mtb isolates. We report here that lab adapted Mtb strains, such as H37Rv, or less virulent Mtb clinical isolates, such as Mtb CDC1551, do not require IL-17 for protective immunity against infection while infection with Mtb HN878 requires IL-17 for early protective immunity. Unexpectedly, Mtb HN878 induces robust production of IL-1β through a TLR-2-dependent mechanism, which supports potent IL-17 responses. We also show that the role for IL-17 in mediating protective immunity against Mtb HN878 is through IL-17 Receptor signaling in non-hematopoietic cells, mediating the induction of the chemokine, CXCL-13, which is required for localization of T cells within lung lymphoid follicles. Correct T cell localization within lymphoid follicles in the lung is required for maximal macrophage activation and Mtb control. Since IL-17 has a critical role in vaccine-induced immunity against TB, our results have far reaching implications for the design of vaccines and therapies to prevent and treat emerging Mtb strains. In addition, our data changes the existing paradigm that IL-17 is dispensable for primary immunity against Mtb infection, and instead suggests a differential role for IL-17 in early protective immunity against emerging Mtb strains. © 2014 Gopal et al
Is Homosexuality a Paraphilia? The Evidence For and Against
Whether homosexuality should be described as one among many paraphilic sexual interests or an altogether different dimension of sexual interest has long been discussed in terms of its political and social implications. The present article examined the question instead by comparing the major correlates and other features of homosexuality and of the paraphilias, including prevalence, sex ratio, onset and course, fraternal birth order, physical height, handedness, IQ and cognitive neuropsychological profile, and neuroanatomy. Although those literatures remain underdeveloped, the existing findings thus far suggest that homosexuality has a pattern of correlates largely, but not entirely, distinct from that identified among the paraphilias. At least, if homosexuality were deemed a paraphilia, it would be relatively unique among them, taxonometrically speaking
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