409 research outputs found
Topological Hopf algebras, quantum groups and deformation quantization
After a presentation of the context and a brief reminder of deformation
quantization, we indicate how the introduction of natural topological vector
space topologies on Hopf algebras associated with Poisson Lie groups, Lie
bialgebras and their doubles explains their dualities and provides a
comprehensive framework. Relations with deformation quantization and
applications to the deformation quantization of symmetric spaces are describedComment: 13 pages, to appear in the proceedings of the conference "Hopf
algebras in noncommutative geometry and physics" (VUB, Brussels, May 2002
Observation of double star by long-baseline interferometry
This paper serves as a reference on how to estimate the parameters of binary
stars and how to combine multiple techniques, namely astrometry, interferometry
and radial velocities.Comment: F. Millour, A. Chiavassa, L. Bigot, O. Chesneau, A. Meilland \& P.
Stee. What can the highest angular resolution bring to stellar astrophysics?,
69-70, EDP sciences, 2015, EAS publication series, 978-2-7598-1833-4.
\<10.1051/eas/1569020\>.
\<http://www.eas-journal.org/articles/eas/abs/2014/04/contents/contents.html\&g
Three Essays in Law and Economics
This dissertation investigates three relevant topics in law and economics literature. The first chapter explores the effectiveness of a crime prevention policy in Detroit, Project Green Light. This initiative began in 2016 and was aimed at reducing crime around high-risk businesses. Reductions in crime can be found in the business block that housed the green light, with a potential diffusion of benefits to their immediate neighbors. Using calls for service produces mixed results and suggest that there may be an increase in proactive policing within these areas. Lastly, response times do appear to decrease significantly. The second chapter empirically evaluates the dominant theory of plea bargaining in economics, using police officer deaths as plausibly exogenous variation to the sentencing process. We argue these deaths are salient to the potential voter base, thus increasing the probability of conviction at trial, funneling back into the plea bargaining process through harsher plea bargained sentence agreements. Considering only cases that were already in process at the time of a death, and located within the same county as the death, we find a 13\% increase in plea bargaining sentences on average. The final chapter examines the impact of new public prison openings in Florida. Exploiting spatial and temporal variation in each case, I find a nine-month window of increased incarceration rates for those defendants most likely to face incarceration at the new prison. This effect is more pronounced in plea bargained cases, suggesting that prosecutors may be shifting their behavior during this time
Spectro-interferometric observations of interacting massive stars with VEGA/CHARA
We obtained spectro-interferometric observations in the visible of
Lyrae and Sgr using the instrument VEGA of the CHARA interferometric
array. For Lyrae, the dispersed fringe visibilities and differential
phases were obtained in spectral regions containing the H and HeI 6678
lines and the H and HeI 4921 lines. Whereas the source is unresolved in
the continuum, the source of the emission lines is resolved and the photocenter
of the bulk of the H emission exhibits offsets correlated with the
orbital phase. For Sgr, both the continuum and H sources are
resolved, but no clear binary signal is detected. The differential phase shift
across the line reveals that the bulk of the H emission is clearly
offset from the primary
Economic Activity, International Intervention, and Transitional Governance: A Comparative Case Study of Somalia
This paper investigates the impact of international state-building efforts in Somalia on economic development. We use satellite data on night lights to measure economic activity to deal with nonexistent or poor-quality national income accounts. Using the synthetic control method, we find that the establishment of the Transitional Federal Government in 2004 was associated with economic stagnation relative to the years under statelessness. Using nighttime light emissions, we find economic stagnation regardless of whether we use the total lights emitted from the country or the spread of lights across the country. Our empirical findings are consistent with the idea that the exogenously imposed Transitional Federal Government destabilized the country through an incongruity with the informal institutions that had led to development during Somalia\u27s `statelessness.\u2
PISCO2: the new speckle camera of the Nice 76-cm refractor
We present the new speckle camera PISCO2 made in 2010-2012, for the 76-cm
refractor of C\^ote d'Azur Observatory. It is a focal instrument dedicated to
the observation of visual binary stars using high angular resolution speckle
interferometry techniques to partly overcome the degradation caused by the
atmospheric turbulence. Fitted with an EMCCD detector, PISCO2 allows the
acquisition of short exposure images that are processed in real time by our
specially designed software. Two Risley prisms are used for correcting the
atmospheric dispersion. All optical settings are remotely controlled. We have
already been able to observe faint, close binary stars with angular separations
as small as 0".16, and visual magnitudes of about 16. We also have measured
some particularly difficult systems with a magnitude difference between the two
components of about 4 magnitudes. This level of performance is very promising
for the detection and study of large sets of yet unknown (or partly measured)
binaries with close separation and/or large magnitude difference.Comment: 13 pages, 12 figure
Wolf-Rayet stars probed by AMBER/VLTI
Massive stars deeply influence their surroundings by their luminosity and the
injection of kinetic energy. So far, they have mostly been studied with
spatially unresolved observations, although evidence of geometrical complexity
of their wind are numerous. Interferometry can provide spatially resolved
observations of massive stars and their immediate vicinity. Specific geometries
(disks, jets, latitude-dependent winds) can be probed by this technique. The
first observation of a Wolf-Rayet (WR) star (\gamma^2 Vel) with the AMBER/VLTI
instrument yielded to a re-evaluation of its distance and an improved
characterization of the stellar components, from a very limited data-set. This
motivated our team to increase the number of WR targets observed with AMBER. We
present here new preliminary results that encompass several spectral types,
ranging from early WN to evolved dusty WC. We present unpublished data on
WR79a, a massive star probably at the boundary between the O and Wolf- Rayet
type, evidencing some Wolf-Rayet broad emission lines from an optically thin
wind. We also present new data obtained on \gamma^2 Vel that can be compared to
the up-to-date interferometry-based orbital parameters from North et al.
(2007). We discuss the presence of a wind-wind collision zone in the system and
provide preliminary analysis suggesting the presence of such a structure in the
data. Then, we present data obtained on 2 dusty Wolf-Rayet stars: WR48a-b and
WR118, the latter exhibiting some clues of a pinwheel-like structure from the
visibility variations.Comment: This paper will be published in the proceeding of SPIE ``astronomical
Telescopes and Instrumentation: Optical and Infrared Interferometry'
Perfluorochemical (PFC) liquid enhances recombinant adenovirus vector-mediated viral interleukin-10 (AdvIL-10) expression in rodent lung
Adenovirus and cationic liposome mediated transfer of Interleukin-10 (IL-10), a potent anti-inflammatory cytokine, has been shown to decrease pro-inflammatory cytokine levels and overall lung inflammation in models of lung transplantation and injury. Limitations to current approaches of IL-10 gene therapy include poor vector delivery methods and pro-inflammatory properties of human IL-10 under certain conditions. We hypothesize that using perfluorochemical (PFC) liquid to deliver the highly homologous viral IL-10 (vIL-10), which is predominantly anti-inflammatory with minimal pro-inflammatory activities, can potentially be a more effective strategy to combat inflammatory lung diseases. In this study, we compare the use of PFC liquid versus aerosolized method to deliver adenovirus encoding the vIL-10 gene (AdvIL-10) in C57Bl6 mice. Detectable vIL-10 levels were measured from bronchoalveolar lavage fluid and lung homogenates at one, four, ten and thirty days after AdvIL-10. Furthermore, we determined if use of PFC liquid could allow for the use of a lower dose of AdvIL-10 by comparing the levels of detectable vIL-10 at different doses of AdvIL-10 delivered +/- PFC liquid. Results showed that PFC liquid enhanced detectable vIL-10 by up to ten fold and that PFC liquid allowed the use of ten-fold less vector. PFC liquid increased detectable vIL-10 in lung homogenates at all time points; however, the increase in detectable vIL-10 in BAL fluid peaked at four days and was no longer evident by thirty days after intratracheal instillation. In summary, this is the first report utilizing PFC liquid to enhance the delivery of a potentially therapeutic molecule, vIL-10. We believe this strategy can be used to perform future studies on the use of the predominantly anti-inflammatory vIL-10 to treat inflammatory lung diseases
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