University of Georgia

About: University of Georgia is a education organization based out in Athens, Georgia, United States. It is known for research contribution in the topics: Population & Gene. The organization has 41934 authors who have published 93622 publications receiving 3713212 citations. The organization is also known as: UGA & Franklin College.

Cognitive Strategies and Learning from the World Wide Web.

Abstract: The purpose of this study was to identify the strategies used by adult learners in an open-ended hypermedia information system. Four participants were drawn from an introductory educational technology course that incorporated a unit on telecommunications. Participants completed a survey measuring reported knowledge in three domains (metacognitive, system, and subject) as well as self-efficacy toward technology. They then identified a personal search topic, and searched the World Wide Web for information using Netscape®, thinking aloud as they searched. Data collection and analysis occurred in several phases: scripting the search, reading through the data, segmenting according to research question, encoding, and aggregating. Three major findings related to hypermedia information systems resulted from this study: (a) a variety of strategies are used by learners; (b) self-reported knowledge appears to affect the strategies used; and (c) perceptions of disorientation and perceived self-efficacy influence the strategies used. Implications related to emerging information technologies and open-ended learning environments are considered.

Pseudomonas syringae: what it takes to be a pathogen.

Abstract: Pseudomonas syringaeuses a multitude of virulence factors to infect plants. In this Review, Xin and colleagues highlight key virulence strategies — immune suppression and water soaking — that allow this bacterium to become a successful pathogen under the right environmental conditions. Pseudomonas syringae is one of the best-studied plant pathogens and serves as a model for understanding host–microorganism interactions, bacterial virulence mechanisms and host adaptation of pathogens as well as microbial evolution, ecology and epidemiology. Comparative genomic studies have identified key genomic features that contribute to P. syringae virulence. P. syringae has evolved two main virulence strategies: suppression of host immunity and creation of an aqueous apoplast to form its niche in the phyllosphere. In addition, external environmental conditions such as humidity profoundly influence infection. P. syringae may serve as an excellent model to understand virulence and also of how pathogenic microorganisms integrate environmental conditions and plant microbiota to become ecologically robust and diverse pathogens of the plant kingdom.

Scientific Status Summary: Innovative food packaging solutions

Abstract: The Institute of Food Technologists has issued this Scientific Status Summary to inform readers of recent innovations in food packaging materials

Ecological stoichiometry in freshwater benthic systems: recent progress and perspectives

Abstract: SUMMARY 1. Ecological stoichiometry deals with the mass balance of multiple key elements [e.g. carbon (C), nitrogen (N), phosphorus (P)] in ecological systems. This conceptual framework, largely developed in the pelagic zone of lakes, has been successfully applied to topics ranging from population dynamics to biogeochemical cycling. More recently, an explicit stoichiometric approach has also been used in many other environments, including freshwater benthic ecosystems. 2. Description of elemental patterns among benthic resources and consumers provides a useful starting point for understanding causes of variation and stoichiometric imbalance in feeding interactions. Although there is considerable overlap among categories, terrestrially-derived resources, such as wood, leaf litter and green leaves have substantially higher C : nutrient ratios than other resources of both terrestrial and aquatic origin, such as periphyton and fine particulate organic matter. The elemental composition of these resources for benthic consumers is modulated by a range of factors and processes, including nutrient availability and ratios, particle size and microbial colonisation. 3. Among consumers in benthic systems, bacteria are the most nutrient-rich, followed (in descending order) by fishes, invertebrate predators, invertebrate primary consumers, and fungi. Differences in consumer C : nutrient ratios appear to be related to broad-scale phylogenetic differences which determine body size, growth rate and resource allocation to structural body constituents (e.g. P-rich bone). 4. Benthic consumers can influence the stoichiometry of dissolved nutrients and basal resources in multiple ways. Direct consumption alters the stoichiometry of food resources by increasing nutrient availability (e.g. reduced boundary layer thickness on substrata) or through removal of nutrient-rich patches (e.g. selective feeding on fungal patches within leaf litter). In addition, consumers alter the stoichiometry of resources and dissolved nutrient pools through the return of egested or excreted nutrients. In some cases, consumer excretion supplies a large proportion of the nutrients required by algae and heterotrophic microbes and alters elemental ratios of dissolved nutrient pools. 5. Organic matter decomposition in benthic systems is accompanied by significant changes in the elemental composition of organic matter. Microbial colonisation of leaf litter influences C : nutrient ratios, and patterns of microbial succession (e.g. fungi followed by bacteria) may be under some degree of stoichiometric control. Large elemental imbalances