Association between methicillin-resistant Staphylococcus pseudintermedius carriage and the development of surgical site infections following tibial plateau leveling osteotomy in dogs.

OBJECTIVE: To evaluate the association between preoperative carriage of methicillin-resistant Staphylococcus pseudintermedius (MRSP) and the development of surgical site infections (SSIs) following tibial plateau leveling osteotomy (TPLO) in dogs. DESIGN: Prospective multicenter study. ANIMALS: 549 dogs. PROCEDURES: At 7 veterinary hospitals, swab specimens were obtained from the pharynx, nares, rectum, and skin of dogs admitted for TPLO. Specimens were submitted for culture of MRSP. For each dog, information regarding preoperative and postoperative antimicrobial administration, comorbidities, contact with other dogs, and whether the dog developed an SSI was obtained. Univariable and multivariable analyses were performed to identify variables associated with preoperative and postoperative MRSP colonization and the development of an SSI. RESULTS: Of the 549 study dogs, 24 (4.4%) were identified as MRSP carriers before TPLO and 37 (6.7%) developed an SSI after TPLO. Bacteriologic culture was performed on specimens obtained from 32 of the 37 SSIs, and MRSP was isolated from 11 (34%). Carriers of MRSP (OR, 6.72; 95% confidence interval [CI], 2.12 to 21.4) and Bulldogs (OR, 11.1; 95% CI, 2.07 to 59.3) were at risk for development of an SSI after TPLO, whereas postoperative administration of antimicrobials (OR, 0.36; 95% CI, 0.15 to 0.91) appeared to protect against development of an SSI. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that carriage of MRSP were a risk factor for development of an SSI after TPLO and measures to rapidly identify and treat MRSP carriers are warranted. Postoperative administration of antimicrobials protected against development of an SSI after TPLO.

Electromagnetic scattering and absorption by randomly oriented fibers.

In this paper, we numerically calculate the extinction, scattering, absorption, and radar cross sections for a randomly oriented finite conducting fiber. Calculations in the long (centimeter) and short (infrared) wavelengths are presented and compared with the fixed orientation value when the incident electric field is aligned along the fiber length. The calculations presented in this paper are necessary for the parametrization of fibers to play the role of efficient obscurant and anti-radio frequency interference.

One-way visibility using two parallel aerosol clouds.

In this article, we experimentally and theoretically test the range of applicability of a patent that predicts one-way visibility through two successive parallel aerosol clouds, one scattering dominant and the other absorption dominant. A laboratory environment experiment has been designed to determine the ranges of transmissivity and contrast enhancement that might be of interest for military applications. In this study we show that transmissivities in the several percent range and lower are essential for any reasonable contrast enhancement between the two sides of the clouds.

Extinction efficiencies for metallic fibers in the infrared: erratum.

In this erratum, a correction of a previously computed extinction spectrum of a sample of silver fibers in the infrared [Appl. Opt.48, 5095 (2009)APOPAI0003-693510.1364/AO.48.005095] is reported. The spectrum was inaccurately computed through use of an approximation relating the E-field aligned values to those of the orientationally averaged extinction efficiency. This approximation is very close for spectral points in the vicinity of the primary resonance but not necessarily for those well away from this resonance. Here, the exact theory has been used to produce the spectra.

Visible and infrared optical properties of stacked cone graphite microtubes.

The absorptive and scattering optical properties of heat-treated, vapor-grown, graphite microtubes consisting of nanotubes in a "stacked cone" configuration were investigated through the visible and infrared wavelengths using photoacoustic and other spectrometric techniques. However, computations of these properties involved uncertainties that were not easily resolved; the appropriate dielectric coefficients were presumed to be a combination of the published values for the distinct orientations of graphite, but the correct proportions are not evident and none of the reasonable choices produced satisfactory agreement (within the measurement limits of error). Since both of the primary components of the extinction were measured, the appropriate computational codes were employed in reverse to compute the dielectric coefficients for the graphite microtubes. Differences, primarily for the imaginary index, are most distinct for visible and near infrared wavelengths; in this wavelength region, the imaginary index falls progressively to less than half that for the computed mixture.

Descriptive report of antebrachial growth deformity correction in 17 dogs from 1999 to 2007, using hybrid linear-circular external fixator constructs.

The radiographic and clinical results from 17 dogs (18 limbs) in which hybrid linear-circular external fixators (HLCEF) were used for the correction of antebrachial growth deformities (AGD) are described, retrospectively. Wedge ostectomy and the application of a type IA or IB HLCEF were performed in all cases. Pre- and postoperative AGD measurements, complications, time to staged destabilization and/or fixator removal, cosmesis, and limb function were evaluated. Complications included wire and/or pin tract inflammation (11 limbs) and radial fracture (2 limbs). All dogs had improved function and appearance after surgery. Limb function was assessed as excellent in 13 cases and good in 4 cases. Limb appearance was assessed as excellent in 12 cases and good in 5 cases. This case series substantiates the utility of HLCEF for the correction of AGD in dogs.

Extinction efficiencies for metallic fibers in the infrared.

Mass density normalized extinction has been both measured and computed throughout the infrared for distribution of well-separated synthesized silver fibers. The computational basis is a code originally generated for use with Drudian thin fibers at millimeter wavelengths and modified for application at wavelengths that include molecular and structural (crystalline) resonances as well as thicker fibers. The computation involved convolution of fiber responses over distributions for both fiber lengths and diameters. Agreement between the measured and the computed results was found to be close.

Development of cleaner-burning brick kilns in Ciudad Juarez, Chihuahua, Mexico.

The following results provide a comparison between net airborne contamination produced by the traditional form of kiln used in Northern Mexico and by those modified according to a design by Dr. Robert Marquez. What has become known as the MK style kiln was intended to significantly reduce contaminant emissions. The concept involves covering the kiln with a dome and channeling the output of an active kiln through a second, identical loaded kiln for its additional filtration of the effluents. Kilns of a pair are connected via clay brick channels. The roles are reversed after the initial kiln is refilled. Significant reductions in the particulate and gaseous emissions were achieved in the prototype system, but a connectional problem with recent kiln pairs has also limited the degree of operational success. The problem did not mask the potential of the MK kiln, as will be shown. Additional anticipated benefits to the owners of MK kilns, such as reduced operating cycles and decreased quantities of fuel, also have been verified. Key measurements made during all of the burns were of aerosol densities and buoyancies in the flues, kiln temperatures, and, on a number of occasions, chemical analyses of both aerosol and gaseous effluents. Continuous time histories of aerosol densities for most burns (of a total of -40) provide a basis for examining features and the effects of differing styles of operation with respect to burn efficiency and net contaminant masses. Covering the active kiln with a dome produces a net reduction in dry aerosol effluent mass of a factor between 5 and 10, whereas the addition of a filter kiln produces a net reduction of about a factor of 2. The use of used motor oil as a fuel further reduced aerosol contamination by -1 order of magnitude.

Millimeter-wavelength investigation of fibrous aerosol absorption and scattering properties.

The measurements here are used to examine agreement with a recently developed theory for long-wavelength fibrous aerosol attenuative properties (extinction and components absorption, scattering). This is intended to be the final phase of a long and systematic examination of the theory's key features. In this case the parameters are high conductivities coupled with a broad range of fiber diameters. It is clear that there is a limit on the extinction efficiency or effective extinction cross section per unit fiber volume. This limit is represented by the fiber diameter of translucency, that is, the diameter at which the fiber is not completely opaque to the electromagnetic energy. The transition is approximated by the classical skin depth of the fiber. Above this diameter the peak extinction efficiency decreases with an increase in diameter at approximately the same rate for all conductors. The scattering resonance producing this peak becomes stronger as the diameter increases. Our data confirm that for fiber diameters below the skin depth the character of the attenuation is that of absorption.