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101.
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Sponheimer M Passey BH de Ruiter DJ Guatelli-Steinberg D Cerling TE Lee-Thorp JA 《Science (New York, N.Y.)》2006,314(5801):980-982
Traditional methods of dietary reconstruction do not allow the investigation of dietary variability within the lifetimes of individual hominins. However, laser ablation stable isotope analysis reveals that the delta13C values of Paranthropus robustus individuals often changed seasonally and interannually. These data suggest that Paranthropus was not a dietary specialist and that by about 1.8 million years ago, savanna-based foods such as grasses or sedges or animals eating these foods made up an important but highly variable part of its diet. 相似文献
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Paul D. McGreevy Melissa Starling N.J. Branson Mia L. Cobb Debbie Calnon 《Journal of Veterinary Behavior: Clinical Applications and Research》2012,7(2):103-117
This article reviews the literature on the complex and variable nature of the dog–human dyad and describes the influence of terms such as “dominance” on attitudes that humans have toward dogs. It highlights a legacy of tension between ethology and psychology and notes that some practitioners have skills with dogs that elude the best learning theorists. Despite the widespread appeal of being able to communicate with dogs as dogs do with one another, attempting to apply the intraspecific dog ethogram to human–dog and dog–human interactions may have limited scope. The balance of learning theory and ethology on our interactions with dogs is sometimes elusive but should spur the scientific community to examine skills deployed by the most effective humane practitioners. This process will demystify the so-called whispering techniques and permit discourse on the reasons some training and handling techniques are more effective, relevant, and humane than others. This article explores the mismatch between the use of nonverbal communication of 2 species and offers a framework for future studies in this domain. Technologies emerging from equitation science may help to disclose confusing interventions through the collar and lead and thus define effective and humane use of negative reinforcement. The case for a validated intraspecific and interspecific canid ethogram is also made. 相似文献
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Brandy L. Drury Erin L. Brinkman Jennifer M. Gambino Alison M. Lee Robert W. Wills Michaela J. Beasley 《Veterinary radiology & ultrasound》2020,61(3):353-363
Cervical spinal disorders can lead to life‐threatening respiratory complications. Diaphragmatic dysfunction is attributed to spinal cord morbidity secondary to cervical myelopathy or decompressive surgical intervention. The purpose of this observational case‐control study was to determine the frequency of diaphragmatic dysfunction in dogs with cervical spinal disorders and a control group, the strength of association between cervical myelopathies and decompressive surgery with diaphragm paresis, and the agreement between and clinical usefulness of fluoroscopy, motion‐mode ultrasonography, and radiography for diagnosing diaphragmatic dysfunction. Thirty‐five client‐owned dogs were recruited with 14 control dogs and 21 test dogs. Dogs were evaluated for the presence of diaphragmatic dysfunction using radiography, M‐mode ultrasonography, and fluoroscopy before and after an anesthetic or surgical event. Diaphragmatic dysfunction was observed more frequently in dogs with cervical spinal disease prior to surgery (8/21; 38.1%) compared to control dogs (3/14; 21.4%) but was not statistically significant (P = .30). The occurrence of diaphragmatic dysfunction did not significantly increase following surgical decompression in either group. There was no to slight agreement between all imaging modalities. Most dogs with diaphragmatic dysfunction were asymptomatic. Diaphragmatic dysfunction was not statistically associated with cervical myelopathy or decompressive surgery. Ultrasonography and radiography were not useful diagnostic tests for determining diaphragmatic dysfunction in asymptomatic dogs when compared to fluoroscopy. 相似文献
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Nora Ortinau Samantha Vitale Erin Y. Akin Michaela Beasley Andy Shores 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(3):288-291
Chiari-like malformation (CLM) with syringomyelia (SM) in dogs is particularly prominent in the Cavalier King Charles spaniel breed, but has also been reported in several other small breed dogs. Over a period of 3 years, 23 canine patients were treated surgically for CLM-SM. Surgery consisted of foramen magnum decompression, durotomy, duraplasty, and free autogenous adipose tissue grafting (fat graft). All patients were re-evaluated clinically at least 1 month after surgery and some up to 3 years after surgery. Improvement was noted on all clinical evaluations. A questionnaire was mailed to all 23 owners after a period of at least 1 year after surgery. Seventeen surveys were returned. No patient has required additional surgery to date, 94% (16/17) had some improvement in quality of life after surgery, and none were judged to deteriorate to less than the pre-surgical status. The authors conclude that this surgical procedure, combined with medical therapy, resulted in favorable long-term outcomes. 相似文献
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Tamara F. J. Fitters Sacha J. Mooney Debbie L. Sparkes 《Soil Use and Management》2022,38(1):1033-1043
On average, sugar beet yield in the UK is reduced by 10% due to water limitation. The root system of a plant is responsible for water uptake and hence an extensive root system is crucial to mitigate drought stress. There might be varietal differences when it comes to plant root system architecture but so far none have been reported in sugar beet. This study shows the results of 2 years of field experiments, examining the rooting patterns and overall plant growth of sugar beet under both rainfed and irrigated conditions. In the first year, three varieties were assessed, and in the second year, five varieties. No significant yield differences were found between the rainfed and irrigated treatments, which is likely due to the applied drought stress only being mild in both years. There were, however, significant varietal differences in plant growth and rooting patterns in rainfed plants which were most distinct when plants were subjected to mild drought stress. Varietal differences observed might indicate the possibility of breeding for certain root traits to mitigate drought stress in sugar beet in the future. 相似文献
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A new class of polymeric substances that degrade in the presence of water are formed by the reaction of carboxylic acids with metal ions in the presence of an aldehyde catalyst. Possible uses may be found in agricultural chemicals, packaging, and medicine. Important antipollution aspects are present in many of these applications. 相似文献