63,506 research outputs found
Complications of percutaneous endoscopic gastrostomy in dogs and cats receiving corticosteroid treatment
BACKGROUND: Corticosteroid treatment is commonly required in veterinary patients for treatment of inflammatory, immune‐mediated, neurologic, and neoplastic diseases, which also may require assisted enteral nutrition via percutaneous endoscopic gastrostomy (PEG). OBJECTIVE: To evaluate complications associated with PEG use in dogs and cats receiving corticosteroid treatment. ANIMALS: Forty‐two animals were included in the study: 12 dogs and 2 cats in the steroid group and 26 dogs and 2 cats in the control group. METHODS: Medical records, between January 2006 and March 2015, were reviewed. Patients were included if the PEG tube was in use for at least 24 hours and if complete medical records were available. Patients were assigned to the control group if they were not treated with corticosteroids during PEG use or to the steroid group if they had received corticosteroids during PEG tube use. Complications were classified as minor, moderate, and major in severity. Maximum severity complication rate was compared between groups. RESULTS: The general prevalence of complications was found to be similar between groups (P = .306), but in the steroid group, 43% of the cases developed a major severity complication compared with 18% of the control group (P = .054). CONCLUSION AND CLINICAL IMPORTANCE: Owners of dogs and cats receiving corticosteroids, in which PEG is planned, should be counseled about possible complications beyond those associated with PEG tube usage alone
Quantum Mechanical Treatment of Variable Molecular Composition: From "Alchemical" Changes of State Functions to Rational Compound Design
"Alchemical" interpolation paths, i.e.~coupling systems along fictitious
paths that without realistic correspondence, are frequently used within
materials and molecular modeling and simulation protocols for the estimation of
relative changes in state functions such as free energies. We discuss
alchemical changes in the context of quantum chemistry, and present
illustrative numerical results for the changes of HOMO eigenvalues of the He
atom due to a linear alchemical teleportation---the simultaneous annihilation
and creation of nuclear charges at different locations. To demonstrate the
predictive power of alchemical first order derivatives (Hellmann-Feynman) the
covalent bond potential of hydrogen fluoride and hydrogen chloride is
investigated, as well as the van-der-Waals binding in the water-water and
water-hydrogen fluoride dimer, respectively. Based on converged electron
densities for one configuration, the versatility of alchemical derivatives is
exemplified for the screening of entire binding potentials with reasonable
accuracy. Finally, we discuss constraints for the identification of non-linear
coupling potentials for which the energy's Hellmann-Feynman derivative will
yield accurate predictions
Serum Biochemical Phenotypes in the Domestic Dog
The serum or plasma biochemical profile is essential in the diagnosis and monitoring of systemic disease in veterinary medicine, but current reference intervals typically take no account of breed-specific differences. Breed-specific hematological phenotypes have been documented in the domestic dog, but little has been published on serum biochemical phenotypes in this species. Serum biochemical profiles of dogs in which all measurements fell within the existing reference intervals were retrieved from a large veterinary database. Serum biochemical profiles from 3045 dogs were retrieved, of which 1495 had an accompanying normal glucose concentration. Sixty pure breeds plus a mixed breed control group were represented by at least 10 individuals. All analytes, except for sodium, chloride and glucose, showed variation with age. Total protein, globulin, potassium, chloride, creatinine, cholesterol, total bilirubin, ALT, CK, amylase, and lipase varied between sexes. Neutering status significantly impacted all analytes except albumin, sodium, calcium, urea, and glucose. Principal component analysis of serum biochemical data revealed 36 pure breeds with distinctive phenotypes. Furthermore, comparative analysis identified 23 breeds with significant differences from the mixed breed group in all biochemical analytes except urea and glucose. Eighteen breeds were identified by both principal component and comparative analysis. Tentative reference intervals were generated for breeds with a distinctive phenotype identified by comparative analysis and represented by at least 120 individuals. This is the first large-scale analysis of breed-specific serum biochemical phenotypes in the domestic dog and highlights potential genetic components of biochemical traits in this species
Turbulence Time Series Data Hole Filling using Karhunen-Loeve and ARIMA methods
Measurements of optical turbulence time series data using unattended
instruments over long time intervals inevitably lead to data drop-outs or
degraded signals. We present a comparison of methods using both Principal
Component Analysis, which is also known as the Karhunen--Loeve decomposition,
and ARIMA that seek to correct for these event-induced and mechanically-induced
signal drop-outs and degradations. We report on the quality of the correction
by examining the Intrinsic Mode Functions generated by Empirical Mode
Decomposition. The data studied are optical turbulence parameter time series
from a commercial long path length optical anemometer/scintillometer, measured
over several hundred metres in outdoor environments.Comment: 8 pages, 9 figures, submitted to ICOLAD 2007, City University,
London, U
Density Functional Study of Ternary Topological Insulator Thin Films
Using an ab-initio density functional theory based electronic structure
method with a semi-local density approximation, we study thin-film electronic
properties of two topological insulators based on ternary compounds of Tl
(Thallium) and Bi (Bismuth). We consider TlBiX (X=Se, Te) and Bi_2_2_3$ (X=Se, Te). With this property in combination with
a structurally perfect bulk crystal, the latter ternary compound has been found
to have improved surface electronic transport in recent experiments. In this
article, we discuss the nature of surface states, their locations in the
Brillouin zone and their interactions within the bulk region. Our calculations
suggest a critical thin film thickness to maintain the Dirac cone which is
significantly smaller than that in binary Bi-based compounds. Atomic
relaxations or rearrangements are found to affect the Dirac cone in some of
these compounds. And with the help of layer-projected surface charge densities,
we discuss the penetration depth of the surface states into the bulk region.
The electronic spectrum of these ternary compounds agrees very well with the
available experimental results.Comment: 9 pages, 11 figures, 1 table, Accepted for publication in Physical
Review
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