144 research outputs found
Associations between neutering and idiopathic epilepsy in Labrador retrievers and Border collies under primary veterinary care in the UK
There are sparse published scientific data on associations between neutering and the severity and survival of dogs with idiopathic epilepsy. This study aimed to explore the timing of neutering with respect to onset of seizures in dogs with idiopathic epilepsy. Associations between neutering and both age of onset of seizures and the occurrence of cluster seizures or status epilepticus were examined. Survival analysis investigated the effects of sex-neuter categories. The median survival time of Border collies was compared with data previously reported in literature.
The study included veterinary primary-care clinical data on 117 Labrador retrievers and 57 Border collies diagnosed with idiopathic epilepsy from the VetCompass project in the UK. The majority (74.2%; P †0.001) of neutered cases were neutered before the onset of seizures. Age (years) at onset of seizures did not differ between dogs intact at time of onset and dogs neutered before onset of seizures (males 3.6 vs. 3.7; P = 0.468 and females 3.4 vs. 4.1; P = 0.154). Neuter status was not associated with the occurrence of cluster seizures (males P = 0.947 and females P = 0.844). Dogs intact at onset of seizures had longer median survival times than dogs neutered before onset of seizures (males, 1436 days vs. 1234 days; P = 0.019; females, 1778.5 days vs. 1261 days; P = 0.027). Median survival time of 1393 days for Border collies was longer than previously reported (P †0.001). These results do not support recommendations to neuter dogs with idiopathic epilepsy within an evidence-based treatment plan
Higher-order co-occurrences for exploratory point pattern analysis and decision tree clustering on spatial data
Analyzing geographical patterns by collocating events, objects or their attributes has a long history in surveillance and monitoring, and is particularly applied in environmental contexts, such as ecology or epidemiology. The identification of patterns or structures at some scales can be addressed using spatial statistics, particularly marked point processes methodologies. Classification and regression trees are also related to this goal of finding "patterns" by deducing the hierarchy of influence of variables on a dependent outcome. Such variable selection methods have been applied to spatial data, but, often without explicitly acknowledging the spatial dependence. Many methods routinely used in exploratory point pattern analysis are2nd-order statistics, used in a univariate context, though there is also a wide literature on modelling methods for multivariate point pattern processes. This paper proposes an exploratory approach for multivariate spatial data using higher-order statistics built from co-occurrences of events or marks given by the point processes. A spatial entropy measure, derived from these multinomial distributions of co-occurrences at a given order, constitutes the basis of the proposed exploratory methods. © 2010 Elsevier Ltd
Dilatonic Black Holes with Gauss-Bonnet Term
We discuss black holes in an effective theory derived from a superstring
model, which includes a dilaton field, a gauge field and the Gauss-Bonnet term.
Assuming U(1) or SU(2) symmetry for the gauge field, we find four types of
spherically symmetric solutions, i.e., a neutral, an electrically charged, a
magnetically charged and a ``colored'' black hole, and discuss their
thermodynamical properties and fate via the Hawking evaporation process. For
neutral and electrically charged black holes, we find critical point and a
singular end point. Below the mass corresponding to the critical point,
nosolution exists, while the curvature on the horizon diverges and anaked
singularity appears at the singular point. A cusp structure in the mass-entropy
diagram is found at the critical point and black holes on the branch between
the critical and singular points become unstable. For magnetically charged and
``colored" black holes, the solution becomes singular just at the end point
with a finite mass. Because the black hole temperature is always finite even at
the critical point or the singular point, we may conclude that the evaporation
process will not be stopped even at the critical point or the singular point,
and the black hole will move to a dynamical evaporation phase or a naked
singularity will appear.Comment: 31pages, 11figures, LaTex styl
Combined in-beam gamma-ray and conversion electron spectroscopy with radioactive ion beams
Volume: 63Peer reviewe
Measurement of the Mass Splittings between the States
We present new measurements of photon energies and branching fractions for
the radiative transitions: Upsilon(2S)->gamma+chi_b(J=0,1,2). The masses of the
chi_b states are determined from the measured radiative photon energies. The
ratio of mass splittings between the chi_b substates,
r==(M[J=2]-M[J=1])/(M[J=1]-M[J=0]) with M the chi_b mass, provides information
on the nature of the bbbar confining potential. We find
r(1P)=0.54+/-0.02+/-0.02. This value is in conflict with the previous world
average, but more consistent with the theoretical expectation that r(1P)<r(2P);
i.e., that this mass splittings ratio is smaller for the chi_b(1P) triplet than
for the chi_b(2P) triplet.Comment: 11 page postscript file, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Radiative Decay Modes of the Meson
Using data recorded by the CLEO-II detector at CESR we have searched for four
radiative decay modes of the meson: ,
, , and . We
obtain 90% CL upper limits on the branching ratios of these modes of , , and
respectively.Comment: 15 page postscript file, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
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