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991.
Alison B. Adams Jennifer Pontius Gillian L. Galford Scott C. Merrill David Gudex-Cross 《Landscape Ecology》2018,33(4):641-658
Purpose
Accurately assessing forest carbon storage on a landscape scale is critical to understanding global carbon cycles and the effects of land cover changes on ecological processes. Calculations of regional-scale forest carbon storage that rely on maps of land cover typically reflect only coarse forest classes. How differences in carbon stored by different tree species may affect such assessments is largely unexplored. We examined a range of forest carbon storage models to understand the effects of forest type specificity on carbon storage estimates in the northeastern United States.Methods
Models estimated forest carbon in total aboveground and coarse root biomass based on three levels of forest classification specificity: (1) relative basal area by species, (2) species associations, and (3) broad forest types per IPCC (in: IPCC guidelines for national greenhouse gas inventories, IPCC, Japan, 2006) guidelines.Results
The specificity of forest type classifications influenced results with generally lower carbon storage estimates resulting from higher-specificity forest classifications. The two most specific models, with mean carbon storage estimates of 103–107 Mg/ha, were most accurate compared to field validation points. These estimates are greater than 2013 field-based U.S. Forest Service estimates (84–90 Mg/ha).Conclusions
There are many sources of uncertainty in landscape-scale carbon storage assessments. Here we show that improving detail in one of these sources, forest stand composition, increases the accuracy of these assessments, and better reflects carbon storage patterns across heterogeneous landscapes. While more work is needed, particularly to improve stand age maps, this information can inform the interpretation of current carbon storage estimates and improve future estimates in heterogeneous forests.992.
993.
994.
Scott M. Salom Nicholas D. Stone Stephen R. Clarke Jeffrey G. Fidgen Brian Ward Quintin McClellan Brinkley Benson 《Integrated Pest Management Reviews》2001,6(3-4):303-310
The Southern Pine Beetle (SPB) is a major pest in southern U.S.A., Mexico, and Central America. Enormous resources in terms of funding, personnel, and effort have been allocated for research and development of pest management tools for this pest over the past century. Access to information from journal articles, reports, fact sheets, etc. does require some effort and is often incomplete and difficult to obtain. The emergence of the Internet now allows rapid access to information from diverse sources. We have created a comprehensive website entitled, 'The Southern Pine Beetle Internet Control Center' (SPBICC) (www.spbicc.vt.edu). The goal of the site is to provide all available resources on SPB to anyone with access to the Internet. It is also designed to increase communication among researchers and professionals to help advance the management of this pest. The site is interactive, which permits constant updating without contacting a webmaster. Attributes of the site include background information in the form of fact sheets, reviews, and government handbooks; an interactive diagnostic identification key for SPB and other bark beetles; a searchable expertise directory; a calendar of SPB-related events; a discussion forum; an online SPB spot growth predictive model; a searchable bibliographic database; a webcrawler designed to search for SPB-related websites, and more. Web-based tools were developed to integrate relational databases as the functional base of this site. The dynamic nature of the SPBICC makes it a powerful tool and a model for development of websites for other major agricultural or forest pests. 相似文献
995.
Serial subculturing of an alfalfa field isolate of Verticillium albo-atrum produced two variants which were significantly less virulent than the original. When conidia of the original isolate, stored at − 70 °C, were infused into alfalfa cuttings, the pathogen grew from spore trapping sites into contiguous vessels and began to sporulate within 24 h. The frequency of vessels in which sporulation occurred at 24 h was similar in alfalfa genotypes known to differ in disease ratings and in host resistance to lateral penetration of vessels. With conidia of the two variants as inoculum, hyphae were found to penetrate much more extensively from trapping
ites into adjacent vessels by 24 h. However, the more virulent original isolate sporulated two to three times more frequently. An isolate of V. albo-atrum from potato, which was non-pathogenic to alfalfa, had limited lateral penetrating ability in alfalfa but never sporulated by 24 h in laterally penetrated vessels. Of parameters studied, including sporulation and radial growth, only early vascular sporulation in laterally penetrated vessels correlated with the greater virulence of the original alfalfa isolate. 相似文献
996.
Chlorpheniramine maleate (2 mg/cat every 12 h orally) and a fatty acid supplement (0.5 ml/cat every 24 h orally) were administered in combination to 11 pruritic cats. Although none of the cats had responded to the two products when they were administered as single therapeutic agents, six of the cats (54%) had an excellent response to the combination. Adverse effects were not seen. Under the conditions of this study, the combination of antihistamine (chlorpheniramine) and the omega-3/omega-6 fatty acid-containing supplement exhibited a superior antipruritic effect to either product alone. 相似文献
997.
998.
FEASIBILITY FOR ULTRASOUND‐GUIDED INJECTION OF THE COLLATERAL LIGAMENTS OF THE DISTAL INTERPHALANGEAL JOINT IN HORSES 
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下载免费PDF全文 Danyse Lewis Mike Scott Carrie D. Fischer Stephanie L. Bond Renaud Léguillette 《Veterinary radiology & ultrasound》2016,57(3):299-305
Desmitis of the collateral ligament of the distal interphalangeal joint is a cause of lameness in performance horses. The objective of this prospective, experimental, ex vivo feasibility study was to evaluate the success of ultrasound‐guided injection of the collateral ligaments of the distal interphalangeal joint in the equine forelimb. Seventy‐six ultrasound‐guided dye injections of the collateral ligament of the distal interphalangeal joint were performed on horses’ cadaver limbs. The hooves were sectioned transversely to verify the location of the dye relative to the collateral ligaments and surrounding structures. Evaluations of transverse sections were performed independently by two experienced observers. A scoring system was used to assess injection of the collateral ligament of the distal interphalangeal joint at the proximal, middle, and distal aspect over the length of the ligament. The collateral ligament was injected at any point in 97.4% of cases. The ligament was injected over the entire scored length in 43.2% of cases (32/74), over two scored length areas in 45.9% of cases (34/74), and in one area in 10.8% of cases (8/74). The distal interphalangeal joint and the common digital extensor tendon were also injected in 81.6% (62/76) and 43.4% (33/76) of the cases, respectively. Use of the ultrasound had a positive and negative predictive value of 98% and 9%, respectively. In this study, ultrasound guidance was useful for confirming injection of the collateral ligament of the distal interphalangeal joint but did not prevent injecting the distal interphalangeal joint and the common digital extensor tendon. 相似文献
999.
1000.
Roberto Germano Costa Edvaldo Mesquita Beltrão Filho Solange de Sousa George Rodrigo Beltrão da Cruz Rita de Cássia Ramos do Egypto Queiroga Eliel Nunes da Cruz 《Animal Science Journal》2016,87(5):703-709
Substituting goats' milk for cows' milk could improve the quality of dairy products, because it adds new sensorial characteristics. The aim of this study was to develop a type of yoghurt using goats' milk (25, 50, 75 and 100%) in place of cows' milk and to compare their characteristics. Physicochemical, microbiological and sensory characteristics were evaluated using a nine‐point hedonic scale and purchase intention test. The data obtained in the physicochemical analysis were submitted to regression analysis and the sensory results were evaluated through analysis of variance. Among the physicochemical characteristics of the yoghurts, variation (P < 0.05) of ash, acidity and lactose was observed. Tasters in the sensory analysis indicated that yoghurts up to 50% of goats' milk received favorable averages; with lower scores for higher goats' milk concentrations (75% and 100%). No difference was reported in acidity. Replacing cows' milk with goats' milk in yoghurt preparation promotes variations in the physicochemical characteristics for ash, acidity and lactose. However, it does not cause alterations in the sensory attributes (50% goat milk) and therefore could be considered as an alternative for the production of dairy products. © 2016 Japanese Society of Animal Science 相似文献