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31.
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J A Orsini A M Buonanno D W Richardson D N Nunamaker 《Journal of the American Veterinary Medical Association》1990,197(9):1184-1186
A Salter-Harris type-II fracture of the distal portion of the femur in a 1-year-old Pony of America was repaired by use of lateral plating combined with interfragmentary compression. The configuration of the fracture and the method of internal fixation with a condylar buttress plate were unique and resulted in primary bone healing, seen at the 5-month follow-up examination. 相似文献
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Leaf reflectance at visible and near-infrared wavelengths (400-1000 nm) is related primarily to pigmentation, leaf structure and water content, and is an important tool for studying stress physiology and relationships between plants and their growth environment. We studied reflectance of two co-occurring Alaskan conifers, black spruce (Picea mariana (Mill.) BSP) and white spruce (Picea glauca (Moench) Voss), at elevations from 60 to 930 m a.s.l. along a latitudinal gradient from 61 degrees to 68 degrees N. Black spruce samples were collected from 24 sites and white spruce from 30 sites. Overall, reflectance spectra of the two species were similar, but from 400 to 700 nm, needle reflectance was consistently higher in black spruce than in white spruce (all P 相似文献
35.
Richardson A 《Tree physiology》2000,20(12):825-829
Accurate estimates of root growth rates are important for root system modeling, and the spread of root systems may be an important determinant of belowground site occupancy. Estimating root system growth rates is complicated because missing, discontinuous, and false annual growth rings make root cross sections difficult to age. These irregularities can occur even in roots of dominant conifers with rare or absent stem growth ring abnormalities. Incomplete rings were noted in the root growth rings of nine co-dominant interior Douglas-fir (Pseudotsuga menziesii var. glauca (Beissn.) Franco) trees. Coarse root (> 1.0-cm diameter) elongation rates were estimated by fitting a geometric mean regression line to ring count and lateral distance data. In all nine roots examined, the geometric mean regression slope was well within the range of the 95% confidence interval for the ordinary least squares regression of lateral distance versus age, suggesting that measurement error may have been negligible. Coarse root elongation rates (which ranged from 2.8 to 15.3 cm year(-1) and averaged 7.4 cm year(-1)) in the interior Douglas-fir trees studied were much lower than those reported by others. This discrepancy may be a result of limited soil water availability, soil heterogeneity (both soil water content and soil texture were highly variable across short distances) and fragmentation of belowground growing space. 相似文献
36.
Kate Bottoms Cate Dewey Karen Richardson Zvonimir Poljak 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(5):502-508
This study explored potential biosecurity issues related to the delivery of feed to commercial farms. A pilot study was conducted to collect information about the day-to-day feed delivery, including biosecurity concerns at the level of the feed truck, the driver, and the farm. In addition, a reusable rubber boot was tested in an effort to increase the proportion of farms at which truck drivers wore clean footwear, and to explore an alternative to the standard plastic disposable boots that may be unsafe in winter conditions. Most farms did well in terms of proper dead-stock management and keeping the farm lane and feed bin areas clean. The provision of reusable rubber boots significantly increased the proportion of deliveries in which the driver wore clean footwear. 相似文献
37.
OBJECTIVE: Previous research on nutrition labelling has mainly used subjective measures. This study examines the effectiveness of two types of nutrition label using two objective measures: eye movements and healthiness ratings. DESIGN: Eye movements were recorded while participants made healthiness ratings for two types of nutrition label: standard and standard plus the Food Standards Agency's 'traffic light' concept. SETTING: University of Derby, UK. SUBJECTS: A total of 92 participants (mean age 31.5 years) were paid for their participation. None of the participants worked in the areas of food or nutrition. RESULTS: For the standard nutrition label, participant eye movements lacked focus and their healthiness ratings lacked accuracy. The traffic light system helped to guide the attention of the consumer to the important nutrients and improved the accuracy of the healthiness ratings of nutrition labels. CONCLUSIONS: Consumers have a lack of knowledge regarding how to interpret nutrition information for standard labels. The traffic light concept helps to ameliorate this problem by indicating important nutrients to which to pay attention. 相似文献
38.
Ana Afonso Jose Cortinas Abrahantes Franz Conraths Anouk Veldhuis Armin Elbers Helen Roberts Yves Van der Stede Estelle Méroc Kristel Gache Jane Richardson 《Preventive veterinary medicine》2014
During the Schmallenberg virus (SBV) epidemic, the European Food Safety Authority (EFSA) collected data on SBV occurrence across Europe in order to provide an assessment of spread and impact. By May 2013, twenty-nine countries were reporting to EFSA and twenty-two countries had reported cases of SBV. The total number of SBV herds reported was 13,846 and the number of SBV laboratory confirmed herds was 8730. The surveillance activities were based on the detection of SBV clinical cases (either adults or newborns). Malformation in newborns was the most commonly reported clinical sign of SBV-infection. All countries were able to provide the date when the first suspicion of SBV in the herd was reported and nineteen could report the location of the herd at a regional level. This allowed the spread of SBV in Europe to be measured both temporally and spatially. The number of SBV confirmed herds started to increase in December 2011 and two peaks were observed in 2012 (February and May). Confirmed herds continued to be reported in 2012 and into 2013. An increase during winter 2012 and spring 2013 was again observed, but the number of confirmed herds was lower than in the previous year. SBV spread rapidly throughout Europe from the initial area of detection. SBV was detected above the latitude of 60° North, which exceeds the northern expansion observed during the bluetongue virus serotype 8 epidemic in 2006–2009. The impact of SBV was calculated as ratio of the number of herds with at least one malformed SBV positive foetus and the total number of herds in this region. The 75th percentile of the malformations ratio in the various affected countries for the whole reporting period was below 1% and 3% for cattle and sheep herds, respectively. International data collection on emerging diseases represents a challenge as the nature of available data, data quality and the proportion of reported cases may vary widely between affected countries. Surveillance activities on emerging animal diseases are often structured only for case detection making the estimation of infection/diseases prevalence and the investigation of risk factors difficult. The impact of the disease must be determined to allow risk managers to take appropriate decisions. Simple within-herd impact indicators suitable for emerging disease outbreaks should be defined that could be measured as part of routine animal health surveillance programmes and allow for rapid and reliable impact assessment of emerging animal health diseases. 相似文献
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C Richardson P C Jones V Barnard C N Hebert S Terlecki W V Wijeratne 《The Veterinary record》1990,126(12):279-284
Jersey cows from several herds provided 97 fetuses and 24 calves at fixed gestational intervals between 80 and 290 days after conception. The fetuses and calves were killed, weighed and measured and, after dissection, the sizes and weights of a range of skeletal and soft tissues were recorded. Six morphological measurements emerged as most suitable for the determination of developmental age in the normal fetus. By plotting their mean values and 95 per cent tolerance limits, the rates of growth and the variability of each measurement were defined. Long bone length was the most useful single measurement for predicting the developmental age of the fetus. Brain weight, bodyweight, crown-anus length and long bone length showed curvilinear growth patterns; age prediction equations derived from these measurements are complicated to use and additional simplified formulae have been derived. The number of appendicular ossification centres also had predictive value, but it could not be used to determine fetal developmental age between 100 and 160 days gestation. 相似文献