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501.
European Journal of Forest Research - 相似文献
502.
Emily M. Gidcumb Timothy A. Bolton Brie Trusiano Kurt L. Zimmerman Vanessa J. Oakes 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2023,52(1):38-43
A 9-year-old female spayed Boston Terrier presented for diagnostic investigation of lethargy, poor appetite, weight loss, and a marked leukocytosis. Significant muscle wasting and a palpable abdominal mass were present on physical examination. Abdominal imaging revealed the mass to be of small intestinal origin; consequently, an intestinal resection and anastomosis were performed without complication. The histopathologic diagnosis was a gastrointestinal stromal tumor, verified by immunohistochemical positivity to CD117 (KIT). Two weeks after discharge, the leukocytosis had resolved. Though the exact molecular mediator of the severe leukocytosis was undetermined, resolution following tumor removal suggests a paraneoplastic cause. To the authors' knowledge, this is the first reported case of probable paraneoplastic leukocytosis secondary to a gastrointestinal stromal tumor in the dog. Gastrointestinal tract imaging should be performed when this uncommon hematologic abnormality is present. 相似文献
503.
504.
Joseph W. Treichler Kurt C. VerCauteren Charles R. Taylor James C. Beasley 《Pest management science》2023,79(12):4765-4773
BACKGROUND
As the population and range of wild pigs (Sus scrofa) continue to grow across North America, there has been an increase in environmental and economic damages caused by this invasive species, and control efforts to reduce damages have increased concomitantly. Despite the expanding impacts and costs associated with population control of wild pigs, the extent to which wild pig control reduces populations and diminishes environmental and agricultural damages are rarely quantified. The goal of this study is to quantify changes in wild pig relative abundance and subsequent changes in damages caused by invasive wild pigs in response to control.RESULTS
Using a combination of wild pig population surveys, agricultural damage assessments, and environmental rooting surveys across 19 mixed forest-agricultural properties in South Carolina, USA, we quantified changes in wild pig relative abundance and associated damages over a 3-year period following implementation of a professional control program. Following implementation of control efforts, both the number of wild pig detections and estimated abundance decreased markedly. Within 24 months relative abundance was reduced by an average of ~70%, which resulted in a corresponding decline in environmental rooting damage by ~99%.CONCLUSION
Our findings suggest that sustained wild pig control efforts can substantially reduce wild pig relative abundance, which in turn resulted in a reduction in environmental rooting damage by wild pigs. Ultimately this study will help fill critical knowledge gaps regarding the efficacy of wild pig control programs and the effort needed to reduce impacts to native ecosystems, livestock, and crops. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献505.
James L. Cook Kurt S. Schulz G. Josh Karnes Samuel P. Franklin Sherman O. Canapp Jr. Peter J. Lotsikas Noel Fitzpatrick Jason L. Wheeler Kevin S. Stiffler Mitchell Gillick Alan R. Cross Charles M. Walls Mark R. Albrecht Ned Williams David T. Crouch Daniel D. Lewis Antonio Pozzi Patrick Ridge 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(9):971-977
We evaluated mid- to long-term outcomes with respect to function and complications in dogs undergoing canine unicompartmental elbow (CUE) arthroplasty for treatment of medial compartment disease of the elbow. This prospective multicenter case series is the first group of clinical cases to receive CUE arthroplasty. Cases (each elbow that underwent CUE performed by a participating surgeon) were enrolled into an electronic database and prospectively followed to determine and record all associated complications, as well as functional outcomes. There were 103 cases from 18 surgeons. Final follow-up time ranged from 6 to 47 mo with a mean and median of 10 mo. Canine unicompartmental elbow was associated with 1 catastrophic (1%), 11 major (10.7%), and 28 minor (27.2%) complications. Outcomes following CUE were reported as full function in 49 cases (47.6%), acceptable function in 45 cases (43.7%), and unacceptable function in 9 cases (8.7%). We conclude that CUE arthroplasty is an appropriate consideration for treatment of medial compartment disease of the elbow in dogs. 相似文献
506.
Effects of elevated concentrations of atmospheric CO2 and tropospheric O3 on decomposition of fine roots 总被引:2,自引:0,他引:2
Rising atmospheric carbon dioxide (CO2) concentration ([CO2]) could alter terrestrial carbon (C) cycling by affecting plant growth, litter chemistry and decomposition. How the concurrent increase in tropospheric ozone (O3) concentration ([O3]) will interact with rising atmospheric [CO2] to affect C cycling is unknown. A major component of carbon cycling in forests is fine root production, mortality and decomposition. To better understand the effects of elevated [CO2] and [O3] on the dynamics of fine root C, we conducted a combined field and laboratory incubation experiment to monitor decomposition dynamics and changes in fine root litter chemistry. Free-air CO2 enrichment (FACE) technology at the FACTS-II Aspen FACE project in Rhinelander, Wisconsin, elevated [CO2] (535 microl 1-1) and [O3] (53 nl 1-1) in intact stands of pure trembling aspen (Populus tremuloides Michx.) and in mixed stands of trembling aspen plus paper birch (Betula papyrifera Marsh.) and trembling aspen plus sugar maple (Acer saccharum Marsh.). We hypothesized that the trees would react to increased C availability (elevated [CO2]) by increasing allocation to C-based secondary compounds (CBSCs), thereby decreasing rates of decomposition. Because of its lower growth potential, we reasoned this effect would be greatest in the aspen-maple community relative to the aspen and aspen-birch communities. As a result of decreased C availability, we expected elevated [O3] to counteract shifts in C allocation induced by elevated [CO2]. Concentrations of CBSCs were rarely significantly affected by the CO2 and O3 treatments in decomposing fine roots. Rates of microbial respiration and mass loss from fine roots were unaffected by the treatments, although the production of dissolved organic C differed among communities. We conclude that elevated [CO2] and [O3] induce only small changes in fine root chemistry that are insufficient to significantly influence fine root decomposition. If changes in soil C cycling occur in the future, they will most likely be brought about by changes in litter production. 相似文献
507.
Effects of irrigation and coppicing on above-ground growth, physiology, and fine-root dynamics of two field-grown hybrid poplar clones 总被引:6,自引:0,他引:6
Donald I. Dickmann Phu V. Nguyen Kurt S. Pregitzer 《Forest Ecology and Management》1996,80(1-3):163-174
To determine the effects of irrigation and coppicing on above- and below-ground growth dynamics, a plantation of Populus × euramericana cv. ‘Eugenei’ and Populus tristis × Populus balsamifera cv. ‘Tristis 1’ was established in May 1984 on a level site in East Lansing, MI, USA. Supplemental water in the form of drip irrigation was applied to half the trees beginning the first growing season. All trees were cut down in March 1988 and the stumps allowed to coppice. Pre- and post-coppice height and diameter growth of ‘Eugenei’ always exceeded that of ‘Tristis’, and the former clone showed a positive response to irrigation, whereas the latter did not. The greater growth of ‘Eugenei’ was primarily due to its full use of the growing season. Post-coppice rates of photosynthesis were not affected by irrigation in either clone, but stomatal conductances were reduced in non-irrigated trees. Analysis of microvideo images taken in minirhizotron tubes buried in the soil close to the trees showed that ‘Tristis’ produced a greater length and number of fine roots in the top 30 cm of soil than ‘Eugenei’, regardless of treatment. Irrigated trees consistently produced more fine roots at 0–30 cm soil depth than non-irrigated trees only in ‘Eugenei’, but both clones showed greater fine-root production in non-irrigated trees at 30–100 cm. Both clones also showed substantial fine-root production in the spring immediately following coppicing, with no evidence of a shock-induced dieback of roots. The root systems of these two poplar genotypes apparently contain sufficient carbon and nitrogen reserves to fuel a spring flush of fine-root growth, even though the tops have been severed during the dormant season. 相似文献
508.
Bernard Tivoli Alain Baranger Carmen M. Avila Sabine Banniza Martin Barbetti Weidong Chen Jenny Davidson Kurt Lindeck Mohammed Kharrat Diego Rubiales Mohamed Sadiki Josefina C. Sillero Mark Sweetingham Fred J. Muehlbauer 《Euphytica》2006,147(1-2):223-253
Summary Necrotrophic pathogens of the cool season food legumes (pea, lentil, chickpea, faba bean and lupin) cause wide spread disease
and severe crop losses throughout the world. Environmental conditions play an important role in the development and spread
of these diseases. Form of inoculum, inoculum concentration and physiological plant growth stage all affect the degree of
infection and the amount of crop loss. Measures to control these diseases have relied on identification of resistant germplasm
and development of resistant varieties through screening in the field and in controlled environments. Procedures for screening
and scoring germplasm and breeding lines for resistance have lacked uniformity among the various programs worldwide. However,
this review highlights the most consistent screening and scoring procedures that are simple to use and provide reliable results.
Sources of resistance to the major necrotrophic fungi are summarized for each of the cool season food legumes. Marker-assisted
selection is underway for Ascochyta blight of pea, lentil and chickpea, and Phomopsis blight of lupin. Other measures such
as fungicidal control and cultural control are also reviewed. The emerging genomic information on the model legume, Medicago truncatula, which has various degrees of genetic synteny with the cool season food legumes, has promise for identification of closely
linked markers for resistance genes and possibly for eventual map-based cloning of resistance genes. Durable resistance to
the necrotrophic pathogens is a common goal of cool season food legume breeders. 相似文献
509.
Shewry PR Gebruers K Andersson AA Aman P Piironen V Lampi AM Boros D Rakszegi M Bedo Z Ward JL 《Journal of agricultural and food chemistry》2011,59(3):928-933
The EU FP6 HEALTHGRAIN has generated an extensive database on the contents of phytochemicals (alkylresorcinols, tocols, sterols, phenolic acids, folates) and dietary fiber components in the grain of wheat, including analyses of 150 lines grown on a single site in Hungary in 2005 and a smaller set of lines grown under five (three lines) or six (23 lines) different environments (in Hungary in 2005, 2006, and 2007 and in France, Poland, and the United Kingdom in 2007). The lines analyzed included land races and varieties bred between the mid-19th and early 21st centuries. These results have been analyzed to determine whether the contents of these groups of bioactive components in the grain have decreased with the development of intensive plant breeding in the second part of the 20th century. No decreases in the contents of any groups of bioactive components were observed in relation to release date, showing that selection for increased yield and protein quality has been effectively neutral for other grain components. 相似文献
510.
Raysa Roque‐Rivera Alan F. Talhelm Dale W. Johnson Vincent L. Chiang Kurt S. Pregitzer 《植物养料与土壤学杂志》2011,174(5):818-826
Several genes in the aspen genome have been modified to generate stem wood with lower lignin content and an altered lignin composition. Lower lignin in wood reduces the time and energy required for pulping. Further, this modification can also increase the allocation of photosynthate to cellulose and total biomass production, potentially increasing CO2‐sequestration capacity. However, widespread planting of trees with altered lignin content and composition could alter soil organic‐C dynamics in complex ways. To further examine the effects of altered lignin biosynthesis on plant growth and accrual of soil organic C (SOC), we conducted a repeated greenhouse study with four lines of transgenic aspen (Populus tremuloides Michx.) and one wild‐type (control) aspen. Accrual of aspen‐derived SOC was quantified by growing aspen trees (C3 plants) in C4 soil and measuring changes in the natural abundance of δ13C. We measured plant growth, biomass, and C content and combined these data with SOC measurements to create C budgets for the plant mesocosms. Lignin modifications resulted in differences in the accrual of aspen‐derived SOC and total mesocosm C, primarily due to differences in biomass between genetically modified lines of aspen. One genetic alteration (low lignin, line 23) was able to perform similarly or better than the wild‐type aspen (control, line 271) without altering SOC. Alterations in lignin structure (S : G ratios) had negative effects on biomass production and SOC formation. The addition of new (aspen‐derived) SOC was proportional to the loss of existing SOC, evidence for a priming effect. The pool of new SOC was related to total plant biomass, suggesting that the effects of lignin modification on SOC are driven by changes in plant growth. 相似文献