Changes in forest soil organic matter pools after a decade of elevated CO₂ and O₃     

Kirsten S. Hofmockel  Donald R. Zak  Kelly K. Moran 《Soil biology & biochemistry》2011,43(7):1518-1527

The impact of rising atmospheric carbon dioxide (CO₂) may be mitigated, in part, by enhanced rates of net primary production and greater C storage in plant biomass and soil organic matter (SOM). However, C sequestration in forest soils may be offset by other environmental changes such as increasing tropospheric ozone (O₃) or vary based on species-specific growth responses to elevated CO₂. To understand how projected increases in atmospheric CO₂ and O₃ alter SOM formation, we used physical fractionation to characterize soil C and N at the Rhinelander Free Air CO₂-O₃ Enrichment (FACE) experiment. Tracer amounts of ¹⁵NH₄⁺ were applied to the forest floor of Populus tremuloides, P. tremuloides-Betula papyrifera and P. tremuloides-Acer saccharum communities exposed to factorial CO₂ and O₃ treatments. The ¹⁵N tracer and strongly depleted ¹³C-CO₂ were traced into SOM fractions over four years. Over time, C and N increased in coarse particulate organic matter (cPOM) and decreased in mineral-associated organic matter (MAOM) under elevated CO₂ relative to ambient CO₂. As main effects, neither CO₂ nor O₃ significantly altered ¹⁵N recovery in SOM. Elevated CO₂ significantly increased new C in all SOM fractions, and significantly decreased old C in fine POM (fPOM) and MAOM over the duration of our study. Overall, our observations indicate that elevated CO₂ has altered SOM cycling at this site to favor C and N accumulation in less stable pools, with more rapid turnover. Elevated O₃ had the opposite effect, significantly reducing cPOM N by 15% and significantly increasing the C:N ratio by 7%. Our results demonstrate that CO₂ can enhance SOM turnover, potentially limiting long-term C sequestration in terrestrial ecosystems; plant community composition is an important determinant of the magnitude of this response.  相似文献   

Experimental model for removal of snake venom via hemoperfusion in rats     

Maximilian Estevan Oliveira  Jssica Campanholi  Roberta Lima Cavalcante  Felipe Silveira Moreno  Edson Hideaki Yoshida  Murilo Melo Juste Dini  lvio Franco de Camargo Aranha  Jos Carlos Cogo  Lourdes Dias  Stephen Hyslop  Denise Grotto  Valquíria Miwa Hanai‐Yoshida  Yoko Oshima‐Franco 《Journal of Veterinary Emergency and Critical Care》2020,30(3):286-294

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Insecticide rotation scheme restores insecticide susceptibility in thiamethoxam‐resistant field populations of Asian citrus psyllid,Diaphorina citri Kuwayama (Hemiptera: Liviidae), in Florida     

Xue Dong Chen  Surendra Neupane  Hunter Gossett  Kirsten S Pelz‐Stelinski  Lukasz L Stelinski 《Pest management science》2021,77(1):464-473

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Concurrent pituitary and adrenocortical lesions on computed tomography imaging in dogs with spontaneous hypercortisolism     

Kirsten L. van Bokhorst  Hans S. Kooistra  Susanne A.E.B. Boroffka  Sara Galac 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(1):72-78

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LPS-induced sickness behavior is not affected by selenium but is switched off by psychogenic stress in rats     

Mazuco  Túlio R. R.  Biondi  Thalles F.  Silva  Ericka P.  Bernardi  Maria M.  Kirsten  Thiago Berti 《Veterinary research communications》2019,43(4):239-247

Veterinary Research Communications - Sickness behavior (SB) is considered part of the adaptive behavioral and neuroimmune changes that occur in response to inflammatory processes. However, SB is a...  相似文献   

Extraction of RNA from formalin‐fixed,paraffin‐embedded equine placenta     

Pouya Dini  Alejandro Esteller‐Vico  Kirsten E. Scoggin  Peter Daels  Barry A. Ball 《Reproduction in domestic animals》2019,54(3):627-634

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Effect of induced chronic atrial fibrillation on exercise performance in Standardbred trotters          下载免费PDF全文

Rikke Buhl  Helena Carstensen  Eva Zander Hesselkilde  Bjørg Zinkernagel Klein  Karen Margrethe Hougaard  Kirsten Bomberg Ravn  Ameli Victoria Loft‐Andersen  Merle Friederike Fenner  Christian Pipper  Thomas Jespersen 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(4):1410-1419

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MOTOR AND SENSORY NERVE CONDUCTION STUDY IN THE FERRET     

Stella Papageorgiou  Konstantinos Krikonis  Jean-François Quinton  Kirsten Gnirs 《Journal of Exotic Pet Medicine》2018,27(4):38-47

Ferrets are considered a popular small mammal pet, and like other companion animals they are reported to suffer from diseases affecting the neuromuscular system. There currently is a lack of comprehensive electrodiagnostic study regarding the appendicular nerves of ferrets. In this research investigation, 25 domestic ferrets were used for electromyography and motor nerve conduction studies of the tibial, fibular, ulnar, and radial nerves, including H reflexes of the tibial and ulnar nerves, as well as sensory conduction of the fibular nerve. Mean and standard deviations for motor and sensory nerve studies were established. The hypothesis that weight would be correlated with all distal and proximal compound muscle action potential latencies was tested and confirmed for the tibial, fibular, and radial nerves but not the ulnar nerve.  相似文献   

Application of multiplex quantitative polymerase chain reaction methods to detect common bacterial fish pathogens in Nile tilapia,Oreochromis niloticus,hatcheries in Costa Rica     

Adrin Lpez‐Porras  Carolina Elizondo  Aida J. Chaves  Alvin C. Camus  Matt J. Griffin  Kirsten Kenelty  Samantha Barum  Elías Barquero‐Calvo  Esteban Soto 《Journal of the World Aquaculture Society》2019,50(3):645-658

Edwardsiella spp., Streptococcus spp., and Francisella noatunensis subsp. orientalis are some of the most important fish pathogens affecting global tilapia, Oreochromis spp., aquaculture. In Costa Rica, the aquaculture industry is dominated by freshwater‐cultured Nile tilapia, Oreochromis niloticus, which are raised in all seven national provinces. At present, little is known regarding the diversity of pathogens present in these facilities, and definitive identification of agents associated with disease outbreaks are rare. To evaluate the prevalence of common bacterial pathogens in these systems, this study used multiplex quantitative polymerase chain reaction (qPCR) assays targeting Edwardsiella, Streptococcus, and Francisella species as a diagnostic and surveillance tool. In 2017, seven different tilapia hatcheries were visited, and 350 fingerlings were subjected to necropsy and molecular diagnostic evaluation. Fish exhibiting gross signs of disease were subjected to histological and microbiological analysis. For the first time, Edwardsiella anguillarum was recovered and molecularly confirmed from diseased tilapia in Costa Rica. In addition, F. noatunensis subsp. orientalis was identified in a region of Costa Rica where it had not been previously reported.  相似文献   

Anatomical characteristics of thermally modified Eucalyptus nitens wood in an open and closed reactor system     

Maximilian Wentzel  Tim Koddenberg  Holger Militz 《Wood material science & engineering》2020,15(4):223-228

ABSTRACT

Eucalyptus nitens specimens were thermally modified under open and closed systems. The anatomical characteristics from selected modifications that presented similar mass losses were investigated by analyzing images taken from scanning electron microscopy, transmission light microscopy, and X-ray micro-computed tomography. Wood cell wall thickness, fiber, and lumen area were measured and compared to unmodified specimens, and the crack formation after modification was also analyzed. There was only a slight decrease in the measured characteristics when compared to unmodified specimens. The wood cell wall thickness was less affected than the fiber and lumen areas, and both modifications presented similar crack formations. Overall, there were no significant differences between open and closed system modifications in the anatomical structure.  相似文献