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11.
Polychronis Kostoulas Leonidas Leontides William J. Browne Ian A. Gardner 《Preventive veterinary medicine》2009,89(3-4):155-162
The variance partition coefficient (VPC) measures the clustering of infection/disease among individuals with a specific covariate pattern. Covariate-pattern-specific VPCs provide insight to the groups of individuals that exhibit great heterogeneity and should be targeted for intervention. VPCs should be taken into consideration when planning study designs, modeling data and estimating sample sizes. We present a Bayesian discrete mixed model for the estimation of covariate-pattern-specific VPCs when measurement of the infection/disease is based on an imperfect test. The utility of the presented model is demonstrated with three applications. In all cases, imperfect tests biased VPC estimates towards the null but corrected estimates could be obtained by modeling the sensitivity and specificity of the test procedure with beta distributions. The comparison of adjusted VPCs between the intercept only and the fitted models with higher level covariates explained the portion of heterogeneity in the data that was accounted for by the covariates. 相似文献
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O'Toole E Miller CW Wilson BA Mathews KA Davis C Sears W 《Journal of the American Veterinary Medical Association》2004,225(1):58-64
OBJECTIVE: To determine the level of clinical agreement between 2 methods for the measurement of resting energy expenditure (REE). DESIGN: Prospective case series. ANIMALS: 77 dogs. PROCEDURE: Oxygen consumption (Vo2) and CO2 production (Vco2) were measured with an open-flow indirect calorimeter in healthy (n = 10) and ill (67) dogs. Measurements were collected at 3 time periods on 2 days. The Vo2 and the Vco2 measurements were then used to calculate the REE values. RESULTS: Mean values of measured (MREE) and predicted (PREE) REEs in healthy dogs and a dog with medical illnesses or trauma were not significantly different. There was a significant difference on day 2 between the MREE and PREE in the group of dogs recovering from major surgery. More importantly, there was significant variation between the PREE and MREE on an individual-dog basis. The PREE only agreed to within +/- 20% of the MREE in 51% to 57% of the dogs. CONCLUSIONS AND CLINICAL RELEVANCE: The level of agreement between these two methods for determining the 24-hour REE was poor in individual dogs. The level of disagreement between the 2 methods indicates that these methods may not be used interchangeably in a clinical setting. Measurement of REE by use of indirect calorimetry may be the only reliable method of determining REE in an individual ill or healthy dog. 相似文献
14.
William A. Battaglin Mark W. Sandstrom Kathryn M. Kuivila Dana W. Kolpin Michael T. Meyer 《Water, air, and soil pollution》2011,218(1-4):307-322
Fungicides are used to prevent foliar diseases on a wide range of vegetable, field, fruit, and ornamental crops. They are generally more effective as protective rather than curative treatments, and hence tend to be applied before infections take place. Less than 1% of US soybeans were treated with a fungicide in 2002 but by 2006, 4% were treated. Like other pesticides, fungicides can move-off of fields after application and subsequently contaminate surface water, groundwater, and associated sediments. Due to the constant pressure from fungal diseases such as the recent Asian soybean rust outbreak, and the always-present desire to increase crop yields, there is the potential for a significant increase in the amount of fungicides used on US farms. Increased fungicide use could lead to increased environmental concentrations of these compounds. This study documents the occurrence of fungicides in select US streams soon after the first documentation of soybean rust in the US and prior to the corresponding increase in fungicide use to treat this problem. Water samples were collected from 29 streams in 13 states in 2005 and/or 2006, and analyzed for 12 target fungicides. Nine of the 12 fungicides were detected in at least one stream sample and at least one fungicide was detected in 20 of 29 streams. At least one fungicide was detected in 56% of the 103 samples, as many as five fungicides were detected in an individual sample, and mixtures of fungicides were common. Azoxystrobin was detected most frequently (45% of 103 samples) followed by metalaxyl (27%), propiconazole (17%), myclobutanil (9%), and tebuconazole (6%). Fungicide detections ranged from 0.002 to 1.15 ??g/L. There was indication of a seasonal pattern to fungicide occurrence, with detections more common and concentrations higher in late summer and early fall than in spring. At a few sites, fungicides were detected in all samples collected suggesting the potential for season-long occurrence in some streams. Fungicide occurrence appears to be related to fungicide use in the associated drainage basins; however, current use information is generally lacking and more detailed occurrence data are needed to accurately quantify such a relation. Maximum concentrations of fungicides were typically one or more orders of magnitude less than current toxicity estimates for freshwater aquatic organisms or humans; however, gaps in current toxicological understandings of the effects of fungicides in the environment limit these interpretations. 相似文献
15.
İsmail Hakkı Nur William Pérez Horst Erich König 《Anatomia, histologia, embryologia》2021,50(3):658-667
This study aims to reveal the morphological properties of facial nerve and the middle ear in Van cats. Study material was composed of 6 female Van cats. Dissections were performed under a Zoom Stereo Microscope. There was no plexus buccalis in Van cats. The chorda tympani was observed to pass through an opening in the tympanic cavity, emerge through a small opening just behind the retroarticular process, and join the lingual nerve. A rounded anatomical formation with a size of 2.75 ± 0.3 mm was found to be located within the mastoid process of the temporal bone between the facial nerve and the auricular branch of the vagus nerve. The stapes nerve was not present. The geniculate ganglion was very prominent and about 1.00 mm high. The deep petrosal nerve was observed to emerge from the plexus tympanicus. The bulla tympanica was 18.96 ± 0.10 mm long, 13.03 ± 0.20 mm wide and 13.16 ± 0.20 mm high. After leaving the mandibular nerve, the n.tensoris tympani coursed caudally around the a.maxillaris, formed an ansa, entered the tympanic cavity through the canalis musculotubarius and reached an end in the m. tensor tympani. Due to the scarcity of studies on the middle ears of Van cats, it is thought that this study will fill a gap in the field of veterinary anatomy. 相似文献
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Marcos Antonio Camacho da Silva William Natale Renato de Mello Prado Márcio Koiti Chiba 《Journal of plant nutrition》2013,36(4):694-702
ABSTRACT Citrus cultures have a fundamental importance to the Brazilian economy; certain aspects such as plant nutrition, yield, and fruit quality are vital for the citrus industry sustainability. The present study evaluated the nutritional status of manganese in adult Pear orange trees using different lime rates topically applied to the soil. The direct evaluation of lime rates effects on leaf manganese (Mn) levels revealed a decrease of the nutrient correlated to its increased, as well as passage of time between application and measurement. Foliar sampling 30 months after surface lime application evidenced a high correlation of foliar manganese levels with soil base saturation of 10–20 cm. Leaf manganese levels which showed a great probability of high productivity were between 33 and 70 mg kg?1. 相似文献
18.
Kathleen Ella Chow Andrew William Stent Marjorie Milne 《Veterinary radiology & ultrasound》2014,55(1):74-78
A 4‐year‐old German shorthaired pointer presented with collapse and hematochezia. Radiographs showed gas and fluid‐distended small intestines and loss of serosal detail. Ultrasound examination showed hypomotile, fluid‐distended small intestines, and thrombosed jejunal veins. Multiphasic contrast‐enhanced computed tomography was performed and showed a CT “whirl sign,” an important but nonspecific sign of intestinal volvulus in human patients. At surgery, the majority of the small intestine was entangled in the volvulus and showed black discoloration. The patient was euthanized. Postmortem evaluation yielded a diagnosis of jejunoileal mesenteric volvulus secondary to a congenital omphalomesenteric duct remnant. 相似文献
19.
Eva van Gorsel Nicolas Delpierre Ray Leuning Andy Black J. William Munger Steven Wofsy Marc Aubinet Christian Feigenwinter Jason Beringer Damien Bonal Baozhang Chen Jiquan Chen Robert Clement Kenneth J. Davis Ankur R. Desai Danilo Dragoni Sophia Etzold Thomas Grünwald Lianhong Gu Bernhard Heinesch Lucy R. Hutyra Wilma W.P. Jans Werner Kutsch B.E. Law Monique Y. Leclerc Ivan Mammarella Leonardo Montagnani Asko Noormets Corinna Rebmann Sonia Wharton 《Agricultural and Forest Meteorology》2009,149(11):1919
Micrometeorological measurements of nighttime ecosystem respiration can be systematically biased when stable atmospheric conditions lead to drainage flows associated with decoupling of air flow above and within plant canopies. The associated horizontal and vertical advective fluxes cannot be measured using instrumentation on the single towers typically used at micrometeorological sites. A common approach to minimize bias is to use a threshold in friction velocity, u*, to exclude periods when advection is assumed to be important, but this is problematic in situations when in-canopy flows are decoupled from the flow above. Using data from 25 flux stations in a wide variety of forest ecosystems globally, we examine the generality of a novel approach to estimating nocturnal respiration developed by van Gorsel et al. (van Gorsel, E., Leuning, R., Cleugh, H.A., Keith, H., Suni, T., 2007. Nocturnal carbon efflux: reconciliation of eddy covariance and chamber measurements using an alternative to the u*-threshold filtering technique. Tellus 59B, 397–403, Tellus, 59B, 307-403). The approach is based on the assumption that advection is small relative to the vertical turbulent flux (FC) and change in storage (FS) of CO2 in the few hours after sundown. The sum of FC and FS reach a maximum during this period which is used to derive a temperature response function for ecosystem respiration. Measured hourly soil temperatures are then used with this function to estimate respiration RRmax. The new approach yielded excellent agreement with (1) independent measurements using respiration chambers, (2) with estimates using ecosystem light-response curves of Fc + Fs extrapolated to zero light, RLRC, and (3) with a detailed process-based forest ecosystem model, Rcast. At most sites respiration rates estimated using the u*-filter, Rust, were smaller than RRmax and RLRC. Agreement of our approach with independent measurements indicates that RRmax provides an excellent estimate of nighttime ecosystem respiration. 相似文献
20.
Thomas K. Day DVM MS Susan Holcombe VMD William W. Muir II DVM PhD 《Journal of Veterinary Emergency and Critical Care》1993,3(2):90-95
A six-year-old arabian stallion was admitted to The Ohio State University Veterinary Hospital for evaluation and repair of a comminuted fracture of the second phalanx. The horse developed impaired arterial oxygenation during surgey and pulmonary edema post-operatively. We postulate that impaired arterial oxygenation resulted from atelectasis of the dependent lung during annesthesia, and the pulmonary edema occurred following re-expansion of the atelectatic of the initiating cause of the edema, removal of excess lung water from the alveoli, and restoration of normal arterial oxygenation. The horse was fully recovered within 12 hours of initiation of clinical signs of respiratory compromise. The horse was fully recovered within 12 hours of initiation of clinical signs of respiratory compromise. This report describes re-expansion pulmonary edema due to reperfusion injury in a horse, treatment of the condition, and a possible explanation of the pathogenesis of this pulmonary pathology. 相似文献