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A membrane-bound protein kinase occurs in membranes derived from rat skeletal muscle and appears limited to a surface membrane fraction. The enzyme is magnesium dependent, is only minimally stimulated by cyclic nucleotides, and phosphorylates serine and to a lesser extent threonine residues of three membrane proteins with molecular weights of less than 30,000. 相似文献
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Luke D. Bainard Alexander M. Koch Andrew M. Gordon John N. Klironomos 《Soil biology & biochemistry》2012
Previous research has found that conventional agricultural systems adversely affect arbuscular mycorrhizal (AM) fungi. However, there is little information on how more ecologically sustainable agricultural practices such as tree-based intercropping (TBI) influence AM fungal communities. In this study, we investigated whether TBI promotes a more abundant and diverse AM fungal community compared to conventional monocropping (CM). Abundance was estimated by measuring spore abundance and hyphal length in soil, and AM fungal colonization of corn (Zea mays) roots. Overall, AM fungal abundance was similar in both systems as corn roots from the CM and TBI systems were heavily colonized (>50%) by AM fungi throughout the growing season. Additionally, soil samples from the CM and TBI systems contained similar spore densities and hyphal length. Molecular analysis of the AM fungal community was assessed using terminal restriction fragment length polymorphism (T-RFLP) analysis of large subunit rRNA genes amplified from roots in the two cropping systems. A total of fourteen AM fungal phylotypes that belonged to the Glomeraceae were found in the two cropping systems. The TBI system had a higher AM fungal richness and contained several taxa not found in the CM system. Molecular analysis of AM fungal communities also revealed significant temporal and compositional differences between the TBI and CM systems. Within the TBI system, tree species differentially influenced the AM fungal community composition in the alley cropping regions. Future research should focus on determining whether compositional differences among AM fungal communities in CM and TBI systems have a functional effect on crop growth and productivity. 相似文献
54.
Gregory D. Bowie Andrew A. Millward Nikesh N. Bhagat 《Urban Forestry & Urban Greening》2014,13(4):742-755
Geographic Information Systems (GIS) and web-based GIS platforms are typically used by large organizations and government agencies for the purpose of data storage, query, analysis, and spatial data mapping. Google Fusion Tables, however, provides cloud-based computing services for data management and easy user collaboration through the Google Maps interface. Fusion Tables are oriented towards smaller organizations that previously were unable to publish data online due to limitations of database knowledge, high cost of start-up, and restrictions on implementation. In this research project, we assess the functionality and limitations of Fusion Tables and associated API as a spatial data management system by programming an interactive web-based mapping platform, the CityTrees.ca Project, designed to showcase the benefits of trees growing on the campus of Ryerson University, Toronto. Specifically, Fusion Tables functionality, such as data storage and manipulation, is used to build a query interface (both attribute and spatial) that permits users of CityTrees.ca to search for and map trees by species, diameter, height, and location. We found that Fusion Tables performed well as a storage medium for our campus tree data, which could easily be explored through our creation of a JavaScript-enabled query tool. Our project provides a unique roadmap for small to medium-sized urban forestry organizations and environmental non-profits seeking to create interactive mapping applications where data privacy and advanced spatial analysis are not fundamental. 相似文献
55.
All anions or cations were removed from potato extract and were replaced by a single, naturally occurring anion or cation in an effort to determine the relative effect of each on the sloughing of potato tissue. The treated extracts were used in cooking soaked potato tissue slices. In the anion series, citrate caused the greatest amount of sloughing. Other cooking media and treatments in decreasing order of effectiveness were untreated extract, malate, oxalate, chloride, and distilled water. In the cation series, sodium and potassium caused significantly more sloughing than the untreated extract. Magnesium and calcium firmed the potato tissue, resulting in less sloughing than that obtained with distilled water. 相似文献
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Lawler A 《Science (New York, N.Y.)》2003,299(5613):1653-1654
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Broad-scale monitoring in Alaska has become of increasing interest due to uncertainty about the potential impacts of changing climate on high-latitude ecosystems. The Forest Inventory and Analysis (FIA) program is a national monitoring program for all public and private forestlands in the US, but the program is not currently implemented in the boreal region of Alaska. We provide an overview of the strengths and weaknesses of the FIA system for monitoring the potential impact of climate change on Alaska’s species, communities, and ecosystems. The primary strength of the system is a scientifically rigorous design-based statistical estimation method that produces estimates of forest attributes with known sampling error and quantifiable measurement error. The weaknesses of the system include low power for small area estimates, lack of spatial context and contiguity, and difficulty in inferring causality of factors when changes in monitored attributes are detected.Climate change is expected to impact many components of boreal ecosystems, but for most indicators the direction and magnitude of change are difficult to predict because of complex interactions among system components. Status and trend information provided by FIA monitoring that could be helpful to conservation decisions includes abundance and rarity of vascular plants, invasive species, biomass and carbon content of vegetation, shifting vegetation species distribution, disturbance frequency, type, and impact, and wildlife habitat characteristics. Because of unique factors such as the low level of infrastructure, modifications to the FIA monitoring system used in the conterminous US have been proposed for Alaska. Remote sensing data would play a greater role in meeting monitoring objectives, and sampling intensity of field plots would be reduced. Coordination with other national, regional, and local monitoring efforts provides potential for increased understanding of change in boreal ecosystems at multiple scales. 相似文献
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Simpson BS Landsberg GM Reisner IR Ciribassi JJ Horwitz D Houpt KA Kroll TL Luescher A Moffat KS Douglass G Robertson-Plouch C Veenhuizen MF Zimmerman A Clark TP 《Veterinary therapeutics : research in applied veterinary medicine》2007,8(1):18-31
Canine separation anxiety is a common behavioral problem presented to veterinarians. Associated behaviors are distressing to both dog and owner, have the potential to disrupt the human-companion animal bond, and may lead to euthanasia. The results of this study demonstrate the clinical efficacy and safety of Reconcile (fluoxetine, 1 to 2 mg/kg/day [0.45 to 0.91 mg/lb/day]), in conjunction with behavior management, for the treatment of canine separation anxiety. The beef flavored chewable formulation was palatable to treated dogs and easy to administer. This study provides to veterinarians and owners valuable information about an effective separation anxiety treatment plan that combines use of Reconcile with behavior modification. 相似文献