University of North Carolina at Charlotte

About: University of North Carolina at Charlotte is a education organization based out in Charlotte, North Carolina, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 8772 authors who have published 22239 publications receiving 562529 citations. The organization is also known as: UNC Charlotte & UNCC.

Nitrifying and denitrifying pathways of methanotrophic bacteria

Abstract: Nitrous oxide, a potent greenhouse gas and ozone-depleting molecule, continues to accumulate in the atmosphere as a product of anthropogenic activities and land-use change. Nitrogen oxides are intermediates of nitrification and denitrification and are released as terminal products under conditions such as high nitrogen load and low oxygen tension among other factors. The rapid completion and public availability of microbial genome sequences has revealed a high level of enzymatic redundancy in pathways terminating in nitrogen oxide metabolites, with few enzymes involved in returning nitrogen oxides to dinitrogen. The aerobic methanotrophic bacteria are particularly useful for discovering and analysing diverse mechanisms for nitrogen oxide production, as these microbes both nitrify (oxidize ammonia to nitrite) and denitrify (reduce nitrate/nitrite to nitrous oxide via nitric oxide), and yet do not rely on these pathways for growth. The fact that methanotrophs have a rich inventory for nitrogen oxide metabolism is, in part, a consequence of their evolutionary relatedness to ammonia-oxidizing bacteria. Furthermore, the ability of individual methanotrophic taxa to resist toxic intermediates of nitrogen metabolism affects the relative abundance of nitrogen oxides released into the environment, the composition of their community, and the balance between nitrogen and methane cycling.

Molecular Diversity of a North Carolina Wastewater Treatment Plant as Revealed by Pyrosequencing

Abstract: We report the results of pyrosequencing of DNA collected from the activated sludge basin of a wastewater treatment plant in Charlotte, NC. Using the 454-FLX technology, we generated 378,601 sequences with an average read length of 250.4 bp. Running the 454 assembly algorithm over our sequences yielded very poor assembly, with only 0.3% of our sequences participating in assembly of significant contigs. Of the 117 contigs greater than 500 bp long that were assembled, the most common annotations were to transposases and hypothetical proteins. Comparing our sequences to known microbial genomes showed nonspecific recruitment, indicating that previously described taxa are only distantly related to the most abundant microbes in this treatment plant. A comparison of proteins generated by translating our sequence set to translations of other sequenced microbiomes shows a distinct metabolic profile for activated sludge with high counts for genes involved in metabolism of aromatic compounds and low counts for genes involved in photosynthesis. Taken together, these data document the substantial levels of microbial diversity within activated sludge and further establish the great utility of pyrosequencing for investigating diversity in complex ecosystems.

Leveraging change blindness for redirection in virtual environments

Abstract: We present change blindness redirection, a novel technique for allowing the user to walk through an immersive virtual environment that is considerably larger than the available physical workspace. In contrast to previous redirection techniques, this approach, based on a dynamic environment model, does not introduce any visual-vestibular conflicts from manipulating the mapping between physical and virtual motions, nor does it require breaking presence to stop and explicitly reorient the user. We conducted two user studies to evaluate the effectiveness of the change blindness illusion when exploring a virtual environment that was an order of magnitude larger than the physical walking space. Despite the dynamically changing environment, participants were able to draw coherent sketch maps of the environment structure, and pointing task results indicated that they were able to maintain their spatial orientation within the virtual world. Only one out of 77 participants across both both studies definitively noticed that a scene change had occurred, suggesting that change blindness redirection provides a remarkably compelling illusion. Secondary findings revealed that a wide field-of-view increases pointing accuracy and that experienced gamers reported greater sense of presence than those with little or no experience with 3D video games.

Reexamining the Relationship between Academic Achievement and Social Behavior.

Abstract: Numerous studies have demonstrated the comorbidity of achievement and behavior problems in students identified with learning disabilities and emotional disturbance. The causal basis for this relationship has not been demonstrated, but several theories regarding the association have been posited, and potential benefits related to prevention keep interest in the connection alive. This article briefly reviews the background for original and continuing focus on behavior and achievement and sets the context for it by looking over some of the work that has been done. It also provides an empirical analysis with outcomes that are contrary to most of those previously reported. It presents findings as a base for directing attention to a fundamental goal of positive behavior interventions and supports (i.e., teaching behavior as well as academic skills in efforts to prevent learning problems and failure in school).