17,731 research outputs found
How Many Templates for GW Chirp Detection? The Minimal-Match Issue Revisited
In a recent paper dealing with maximum likelihood detection of gravitational
wave chirps from coalescing binaries with unknown parameters we introduced an
accurate representation of the no-signal cumulative distribution of the
supremum of the whole correlator bank. This result can be used to derive a
refined estimate of the number of templates yielding the best tradeoff between
detector's performance (in terms of lost signals among those potentially
detectable) and computational burden.Comment: submitted to Class. Quantum Grav. Typing error in eq. (4.8) fixed;
figure replaced in version
An experiment in public education
This is a reprinted version of the article written by Dr. Thelma V. Owen and Dr. M. G. Stemmermann that was originally published in Mental Hygiene, Vol. 43, No. 1., in January 1959. The article discusses the negative outcomes of mental illness stigma and the regression in care and treatment that stigma causes. As part of their writings, they are able to include operations of Owen Clinic as positive examples and ways to curve stigma and provide better care. They detail the Club formed by ex-patients and family who began different methods of advocation, from helping new patients to giving panel discussions to various groups. The article contains the remarks given by the panel members. These panels were significant sources of community outreach and mental health awareness in the area and showcase just how instrumental Owen Clinic was in changing rural mental health attitudes.https://mds.marshall.edu/owen_clinic_institute/1027/thumbnail.jp
Pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin after intracoelomic administration in Tortoises (Testudo hermanni)
Enrofloxacin belongs to the fluoroquinolone class of antibiotics. It is commonly used in a variety of reptile species due to its wide spectrum of efficacy, partly due to its formation of an active metabolite ciprofloxacin. Enrofloxacin shows wide disposition variability among all species resulting in large differences in the plasma concentrations of both enrofloxacin and ciprofloxacin. The aim of this study was to evaluate the pharmacokinetics of enrofloxacin and ciprofloxacin after a single intracoelomic injection of 10 mg/kg of enrofloxacin in 9 tortoises (Testudo hermanni). Blood samples were collected at 0, 0.5, 2, 4, 10, 24, 48, 72, 96, 120, 144, 168, 192, 216, 240 and 264 h and analyzed using a validated high performance liquid chromatography (HPLC) florescence method. Plasma concentrations of enrofloxacin were quantifiable in all subjects for up to 240 h, while ciprofloxacin was detected in all subjects up to 120 h. The C (s) of enrofloxacin and ciprofloxacin were 8614 ± 1116 ηg/mL obtained at 2.19 h and 605 ± 43 ηg/mL obtained at 4.23 h, respectively. The values of C/MIC ratio and AUC/MIC ratio of enrofloxacin with a MIC value of 0.5 μg/mL were 17.23 and 132.78, respectively. In conclusion, an administration of 10 mg/kg of enrofloxacin via the intracoelomic route in Hermann’s tortoises produced optimal pharmacodynamic parameters
QCD Heat Kernel in Covariant Gauge
We report the calculation of the fourth coefficient in an expansion of the
heat kernel of a non-minimal, non-abelian kinetic operator in an arbitrary
background gauge in arbitrary space-time dimension. The fourth coefficient is
shown to bring a nontrivial gauge dependence due to the contribution of the
lowest order off-shell gauge invariant structure.Comment: 6 pages + title page, standart LaTe
Modelling and Simulation of Cratering and Ejecta Production During High Velocity Impacts
During an impact event from a high velocity particle (moving at speeds of around 100 m/s or greater) a significant amount of ejecta can be formed and thrown away from the impact point at velocities on the same order as the original impactor. The amount, size distribution, and speed distribution of this ejecta vary with the impact conditions. Predicting this cratering and ejecta phenomena has applications to many areas, including solar system formation, asteroid defense considerations, and micrometeorite impacts on satellites. This paper will look at the physics and modeling of these impacts and the subsequent ejecta formation from these hypervelocity particles. Impacts are modeled using adaptive smooth particle hydrodynamics, and crater volume and ejecta characteristics are quantified and presented. Good agreement with two experimental test cases is obtained
An X-ray and Optical Investigation of the Environments Around Nearby Radio Galaxies
Investigations of the cluster environment of radio sources have not shown a
correlation between radio power and degree of clustering. However, it has been
demonstrated that extended X-ray luminosity and galaxy clustering do exhibit a
positive correlation. This study investigates a complete sample of 25 nearby (z
less than 0.06) radio galaxies which are not cataloged members of Abell
clusters. The environment of these radio galaxies is studied in both the X-ray
and the optical by means of the ROSAT All-Sky Survey (RASS), ROSAT pointed
observations, and the Palomar optical Digitized Sky Survey (DSS). X-ray
luminosities and extents are determined from the RASS, and the DSS is used to
quantify the degree of clustering via the spatial two-point correlation
coefficient, Bgg. Of the 25 sources, 20 are greater than sigma detections in
the X-ray and 11 possessed Bgg's significantly in excess of that expected for
an isolated galaxy. Adding the criterion that the X-ray emission be resolved,
10 of the radio galaxies do appear to reside in poor clusters with extended
X-ray emission suggestive of the presence of an intracluster medium. Eight of
these galaxies also possess high spatial correlation coefficients. Taken
together, these data suggest that the radio galaxies reside in a low richness
extension of the Abell clusters. The unresolved X-ray emission from the other
galaxies is most likely associated with AGN phenomena. Furthermore, although
the sample size is small, it appears that the environments of FR I and FR II
sources differ. FR I's tend to be more frequently associated with extended
X-ray emission (10 of 18), whereas FR II's are typically point sources or
non-detections in the X-ray (none of the 7 sources exhibit extended X-ray
emission).Comment: 28 page postscript file including figures and tables, plus one
landscape table and 5 GIF figure
Unbiased Comparative Evaluation of Ranking Functions
Eliciting relevance judgments for ranking evaluation is labor-intensive and
costly, motivating careful selection of which documents to judge. Unlike
traditional approaches that make this selection deterministically,
probabilistic sampling has shown intriguing promise since it enables the design
of estimators that are provably unbiased even when reusing data with missing
judgments. In this paper, we first unify and extend these sampling approaches
by viewing the evaluation problem as a Monte Carlo estimation task that applies
to a large number of common IR metrics. Drawing on the theoretical clarity that
this view offers, we tackle three practical evaluation scenarios: comparing two
systems, comparing systems against a baseline, and ranking systems. For
each scenario, we derive an estimator and a variance-optimizing sampling
distribution while retaining the strengths of sampling-based evaluation,
including unbiasedness, reusability despite missing data, and ease of use in
practice. In addition to the theoretical contribution, we empirically evaluate
our methods against previously used sampling heuristics and find that they
generally cut the number of required relevance judgments at least in half.Comment: Under review; 10 page
Low voltage control of ferromagnetism in a semiconductor p-n junction
The concept of low-voltage depletion and accumulation of electron charge in
semiconductors, utilized in field-effect transistors (FETs), is one of the
cornerstones of current information processing technologies. Spintronics which
is based on manipulating the collective state of electron spins in a
ferromagnet provides complementary technologies for reading magnetic bits or
for the solid-state memories. The integration of these two distinct areas of
microelectronics in one physical element, with a potentially major impact on
the power consumption and scalability of future devices, requires to find
efficient means for controlling magnetization electrically. Current induced
magnetization switching phenomena represent a promising step towards this goal,
however, they relay on relatively large current densities. The direct approach
of controlling the magnetization by low-voltage charge depletion effects is
seemingly unfeasible as the two worlds of semiconductors and metal ferromagnets
are separated by many orders of magnitude in their typical carrier
concentrations. Here we demonstrate that this concept is viable by reporting
persistent magnetization switchings induced by short electrical pulses of a few
volts in an all-semiconductor, ferromagnetic p-n junction.Comment: 11 pages, 4 figure
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