248 research outputs found
The Design of an Output Data Collection Framework for ns-3
An important design decision in the construction of a simulator is how to enable users to access the data generated in each run of a simulation experiment. As the simulator executes, the samples of performance metrics that are generated beg to be exposed either in their raw state or after having undergone mathematical processing. Also of concern is the particular format this data assumes when externalized to mass storage, since it determines the ease of processing by other applications or interpretation by the user. In this paper, we present a framework for the \ns network simulator for capturing data from inside an experiment, subjecting it to mathematical transformations, and ultimately marshaling it into various output formats. The application of this functionality is illustrated and analyzed via a study of common use cases. Although the implementation of our approach is specific to \ns, this design presents lessons transferrable to other platforms
First Results of the Phase II SIMPLE Dark Matter Search
We report results of a 14.1 kgd measurement with 15 superheated droplet
detectors of total active mass 0.208 kg, comprising the first stage of a 30 kgd
Phase II experiment. In combination with the results of the neutron-spin
sensitive XENON10 experiment, these results yield a limit of |a_p| < 0.32 for
M_W = 50 GeV/c2 on the spin-dependent sector of weakly interacting massive
particle-nucleus interactions with a 50% reduction in the previously allowed
region of the phase space formerly defined by XENON, KIMS and PICASSO. In the
spin-independent sector, a limit of 2.3x10-5 pb at M_W = 45 GeV/c2 is obtained.Comment: 4 pages, 4 figures; PRL-accepted version with corrected SI contour
(Fig. 4
Final Analysis and Results of the Phase II SIMPLE Dark Matter Search
We report the final results of the Phase II SIMPLE measurements, comprising
two run stages of 15 superheated droplet detectors each, the second stage
including an improved neutron shielding. The analyses includes a refined signal
analysis, and revised nucleation efficiency based on reanalysis of
previously-reported monochromatic neutron irradiations. The combined results
yield a contour minimum of \sigma_{p} = 4.2 x 10^-3 pb at 35 GeV/c^2 on the
spin-dependent sector of WIMP-proton interactions, the most restrictive to date
from a direct search experiment and overlapping for the first time results
previously obtained only indirectly. In the spin-independent sector, a minimum
of 3.6 x 10^-6 pb at 35 GeV/c^2 is achieved, with the exclusion contour
challenging the recent CoGeNT region of current interest.Comment: revised, PRL-accepted version with slightly weakened limit contour
The SIMPLE Phase II Dark Matter Search
Phase II of SIMPLE (Superheated Instrument for Massive ParticLe Experiments)
searched for astroparticle dark matter using superheated liquid
CClF droplet detectors. Each droplet generally requires an energy
deposition with linear energy transfer (LET) 150 keV/m for a
liquid-to-gas phase transition, providing an intrinsic rejection against
minimum ionizing particles of order 10, and reducing the backgrounds to
primarily and neutron-induced recoil events. The droplet phase
transition generates a millimetric-sized gas bubble which is recorded by
acoustic means. We describe the SIMPLE detectors, their acoustic
instrumentation, and the characterizations, signal analysis and data selection
which yield a particle-induced, "true nucleation" event detection efficiency of
better than 97% at a 95% C.L. The recoil- event discrimination,
determined using detectors first irradiated with neutrons and then doped with
alpha emitters, provides a recoil identification of better than 99%; it differs
from those of COUPP and PICASSO primarily as a result of their different
liquids with lower critical LETs. The science measurements, comprising two
shielded arrays of fifteen detectors each and a total exposure of 27.77 kgd,
are detailed. Removal of the 1.94 kgd Stage 1 installation period data, which
had previously been mistakenly included in the data, reduces the science
exposure from 20.18 to 18.24 kgd and provides new contour minima of
= 4.3 10 pb at 35 GeV/c in the
spin-dependent sector of WIMP-proton interactions and = 3.6
10 pb at 35 GeV/c in the spin-independent sector. These
results are examined with respect to the fluorine spin and halo parameters used
in the previous data analysis.Comment: 20 pages, 19 figures; accepted Physical Review
A CF3I-based SDD Prototype for Spin-independent Dark Matter Searches
The application of Superheated Droplet Detectors (SDDs) to dark matter
searches has so far been confined to the light nuclei refrigerants C2ClF5 and
C4F10 (SIMPLE and PICASSO, respectively), with a principle sensitivity to
spin-dependent interactions. Given the competitive results of these devices, as
a result of their intrinsic insensitivity to backgrounds, we have developed a
prototype trifluoroiodomethane (CF3I)-loaded SDD with increased sensitivity to
spin-independent interactions as well. A low (0.102 kgd) exposure test
operation of two high concentration, 1 liter devices is described, and the
results compared with leading experiments in both spin-dependent and
-independent sectors. Although competitive in both sectors when the difference
in exposures is accounted for, a problem with fracturing of the detector gel
must be addressed before significantly larger exposures can be envisioned.Comment: revised and updated; accepted Astrop. Phy
To circ or not to circ: clinical and pharmacoeconomic outcomes of a prospective trial of topical steroid versus primary circumcision
PURPOSE: To compare the efficacy and costs of circumcision versus topical treatment using a prospective pharmacoeconomic protocol. MATERIALS AND METHODS: We treated 59 patients (3-10 years of age) randomized into two groups: 29 underwent an 8-week course of topical treatment with 0.2% betamethasone-hyaluronidase cream twice a day; and 30 underwent circumcision. Topical treatment success was defined as complete exposure of the glans. In cases of treatment failure, circumcision was performed and its cost imputed to that of the initial treatment. The pharmacoeconomic aspects were defined according to the Brazilian National Public Health System database and the Brazilian Community Pharmacies Index. RESULTS: The two groups were statistically similar for all clinical parameters evaluated. Topical treatment resulted in complete exposure of the glans in 52% of the patients. Topical treatment was associated with preputial pain and hyperemia. However, treatment suspension was unnecessary. Minor complications were observed in 16.6% of the surgical group patients. The mean cost per patient was US 125.20, respectively, for topical steroid treatment (including the costs related to treatment failure) and circumcision. The total costs were US 3,885.73 for topical treatment and circumcision, respectively. CONCLUSIONS: Topical treatment of phimosis can reduce costs by 27.3% in comparison with circumcision. Therefore, topical treatment of phimosis should be considered prior to the decision to perform surgery.Federal University of São Paulo Department of Urology Section of Pediatric UrologyUNIFESP, Department of Urology Section of Pediatric UrologySciEL
TWO MORE SOCIAL WASP SPECIES (VESPIDAE, POLISTINAE) COLLECT MULLERIAN BODIES FROM CECROPIA TREES (URTICACEAE)
The interactive behaviors of two species of social wasps, Protopolybia chartergoides (Gribodo) and Charterginus fulvus Fox with Cecropia obtusifolia (Cecropiaceae) are described. The use of Cecropia Müllerian bodies by the two wasps is also described, as well as the distribution of this trait in Protopolybia and Charterginus
First Keck Interferometer measurements in self-phase referencing mode: spatially resolving circum-stellar line emission of 48 Lib
Recently, the Keck interferometer was upgraded to do self-phase-referencing (SPR) assisted K-band spectroscopy at R ~ 2000. This means, combining a spectral resolution of 150 km/s with an angular resolution of 2.7 mas, while maintaining high sensitiviy. This SPR mode operates two fringe trackers in parallel, and explores several infrastructural requirements for off-axis phase-referencing, as currently being implemented as the KI-ASTRA project. The technology of self-phasereferencing opens the way to reach very high spectral resolution in near-infrared interferometry. We present the scientific capabilities of the KI-SPR mode in detail, at the example of observations of the Be-star 48 Lib. Several spectral lines of the cirumstellar disk are resolved. We describe the first detection of Pfund-lines in an interferometric spectrum of a Be star, in addition to Br γ. The differential phase signal can be used to (i) distinguish circum-stellar line emission from the star, (ii) to directly measure line asymmetries tracing an asymetric gas density distribution, (iii) to reach a differential, astrometric precision beyond single-telescope limits sufficient for studying the radial disk structure. Our data support the existence of a radius-dependent disk density perturbation, typically used to explain slow variations of Be-disk hydrogen line profiles
Cosmic-ray antiproton constraints on light dark matter candidates
Some direct detection experiments have recently collected excess events that
could be interpreted as a dark matter (DM) signal, pointing to particles in the
10 GeV mass range. We show that scenarios in which DM can self-annihilate
with significant couplings to quarks are likely excluded by the cosmic-ray (CR)
antiproton data, provided the annihilation is S-wave dominated when DM
decouples in the early universe. These limits apply to most of supersymmetric
candidates, eg in the minimal supersymmetric standard model (MSSM) and in the
next-to-MSSM (NMSSM), and more generally to any thermal DM particle with
hadronizing annihilation final states.Comment: Contribution to the proceedings of TAUP-2011 (Munich, 5-9 IX 2011). 4
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