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排序方式: 共有169条查询结果,搜索用时 171 毫秒
71.
Audrey C. Muguet‐Chanoit DVM MS Ji‐Hey Lim DVM PhD Ryan Gallagher DVM Zachary Niman DVM Diplomate ACVIM Neurology Stacy Dillard DVM Diplomate ACVIM Neurology James Campbell DVM PhD Peter Early DVM Diplomate ACVIM Neurology Karen R. Muñana DVM MS Diplomate ACVIM Neurology Courtenay Freeman DVM Marc Kent DVM Diplomate ACVIM Neurology Carley Giovanella DVM Diplomate ACVIM Neurology 《Veterinary surgery : VS》2012,41(2):200-206
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Color defines one aspect of quality for tomato and tomato products. Carotenoid pigments are responsible for the red and orange colors of tomato fruit, and thus color is also of dietary interest. The aims of this study were (1) to determine the relative importance of field sampling and analytical replication when measuring lycopene and beta-carotene in tomato fruit and (2) to determine the effect of yellow shoulder disorder (YSD) on the content of lycopene and beta-carotene in tomato juice and tissue. Our results show that increasing biological replications is an efficient strategy for reducing the experimental error associated with measurements of lycopene and beta-carotene. Analytical replications did not contribute significantly to observed variation, and therefore experimental efficiency will be gained by reducing analytical replications while increasing field replication. We found that YSD significantly reduces lycopene in affected tissue and in juice made from affected fruit. In contrast, beta-carotene concentrations were only reduced in affected tissue but were not significantly reduced in juice. With increasing interest in biofortified crops, modulating the carotenoid profile in tomato by minimizing YSD symptoms represents a strategy for improving tomato fruit quality that is currently supported by grower contract structure and processor grades. 相似文献
75.
Karen L. Webb David Pelletier Audrey N. Maretzki Jennifer Wilkins 《Agriculture and Human Values》1998,15(1):65-75
Several different evaluation issuesare perceived as important by people involved withinnovative projects intended to improve local food andnutrition systems; particularly the establishment oflocal food policy coalitions. Several such coalitionshave been formed in North America, Europe, andAustralia with the goal of improving community foodsecurity and promoting sustainable local food systems.Pioneer coalitions have served as models, yet therehas been little systematic evaluation of thesemodels. A qualitative study was conducted to identifyfactors that may hinder evaluation efforts. In grouptelephone interviews, we sought the views ofacademics, project organizers, and funders, a total of24 key informants. Pressures to evaluate were assessed differently bythe three groups of key informants. Academics felt thefocus of evaluation should be on the effectiveness ofthe process used to discuss issues and formulatepolicies and plans. Project organizers and fundersperceived a need to assess project impact andoutcomes. A lack of suitable evaluation models andmethods was viewed as a formidable barrier. The use ofinappropriate methods and premature impact evaluationwere noted as potential threats to projectsustainability. External constraints and resourcelimitations were also said to inhibit evaluationefforts. It appears that several other factors may also beimpeding progress in conducting more (and more useful)evaluations including: (1) the apparent negativeconnotation of evaluation and the limited benefitsexpected from evaluation by stakeholders, (2) a lackof consensus about important evaluation questions,(3) insufficient evaluation expertise among projectorganizers, and (4) inadequate appreciation ofincreasing accountability pressures. 相似文献
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Audrey A.Sanchez Andrew W.Bartlow Allison M.Chan Jeanne M.Fair Aaron A.Skinner Kelly Hutchins Maria A.Musgrave Emily M.Phillips Brent E.Thompson Charles D.Hathcock 《中国鸟类》2021,(2):141-149
Background: Accurate nestling age is valuable for studies on nesting strategies, productivity, and impacts on repro-ductive success. Most aging guides consist o... 相似文献
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Mathilde Bettembourg Audrey Dardou Alain Audebert Emilie Thomas Julien Frouin Emmanuel Guiderdoni Nourollah Ahmadi Christophe Perin Anne Dievart Brigitte Courtois 《Rice》2017,10(1):45
Background
Plant root systems play a major role in anchoring and in water and nutrient uptake from the soil. The root cone angle is an important parameter of the root system architecture because, combined with root depth, it helps to determine the volume of soil explored by the plant. Two genes, DRO1 and SOR1, and several QTLs for root cone angle have been discovered in the last 5 years.Results
To find other QTLs linked to root cone angle, a genome-wide association mapping study was conducted on two panels of 162 indica and 169 japonica rice accessions genotyped with two sets of SNP markers (genotyping-by-sequencing set with approximately 16,000 markers and high-density-rice-array set with approximately 300,000 markers). The root cone angle of all accessions was measured using a screen protractor on images taken after 1 month of plant growth in the Rhizoscope phenotyping system. The distribution of the root cone angle in the indica panel was Gaussian, but several accessions of the japonica panel (all the bulus from Indonesia and three temperate japonicas from Nepal or India) appeared as outliers with a very wide root cone angle. The data were submitted to association mapping using a mixed model with control of structure and kinship. A total of 15 QTLs for the indica panel and 40 QTLs for the japonica panel were detected. Genes underlying these QTLs (+/?50 kb from the significant markers) were analyzed. We focused our analysis on auxin-related genes, kinases, and genes involved in root developmental processes and identified 8 particularly interesting genes.Conclusions
The present study identifies new sources of wide root cone angle in rice, proposes ways to bypass some drawbacks of association mapping to further understand the genetics of the trait and identifies candidate genes deserving further investigation.78.
Audrey Lustig Daniel B. Stouffer Crile Doscher Susan P. Worner 《Landscape Ecology》2017,32(12):2311-2325
Context
With accelerated land-use change throughout the world, increased understanding of the relative effects of landscape composition and configuration on biological system and bioinvasion in particular, is needed to design effective management strategies. However, this topic is poorly understood in part because empirical studies often fail to account for large gradients of habitat complexity and offer insufficient or even no replication across habitats.Objectives
The aim of this study was to disentangle the independent and interactive effects of landscape composition and landscape configuration on the establishment and spread of invasive insect species.Methods
We explore a spatially-explicit, mechanistic modeling framework that allows for systematic investigation of the impact of changes in landscape composition and landscape configuration on establishment and spread of invasive insect species. Landscape metrics are used as an indicators of invasive insect establishment and spread.Results
We showed that the presence of an Allee effect leads to a balance between the effectiveness of spread and invasion success. Spread is maximized at an intermediate dispersal level and inhibited at both low and high levels of dispersal. The landscape, by either increasing or mitigating the dispersal abilities of a species, can lead to a rate of spread under a dispersal threshold for which density and spread is at the highest.Conclusion
Our study proposes that change in landscape structure is an additional explanation of the highly variable spread dynamics observed in natural and anthropogenic landscapes. Consequently, a landscape-scale perspective could significantly improve spread risk assessment and the design of control or containment strategies.79.
Audrey Geffen 《Aquaculture (Amsterdam, Netherlands)》1979,16(1):83-85
A rotating cage has been designed and tested which prevents the significant buildup of fouling communities and does not add to labor or construction costs. 相似文献
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