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.

The environmental controls that govern the end product of bacterial nitrate respiration

Abstract: In the biogeochemical nitrogen cycle, microbial respiration processes compete for nitrate as an electron acceptor. Denitrification converts nitrate into nitrogenous gas and thus removes fixed nitrogen from the biosphere, whereas ammonification converts nitrate into ammonium, which is directly reusable by primary producers. We combined multiple parallel long-term incubations of marine microbial nitrate-respiring communities with isotope labeling and metagenomics to unravel how specific environmental conditions select for either process. Microbial generation time, supply of nitrite relative to nitrate, and the carbon/nitrogen ratio were identified as key environmental controls that determine whether nitrite will be reduced to nitrogenous gas or ammonium. Our results define the microbial ecophysiology of a biogeochemical feedback loop that is key to global change, eutrophication, and wastewater treatment.

Formation of Viable but Nonculturable Cells

Abstract: It has long been realized that plate counts can dramatically underestimate the total number of bacteria (typically determined by direct microscopic examination) present in samples taken from natural environments. In the late 1970s, several easily performed noncultural methods (Zimmerman et al., 1978; Kogure et al., 1979) for determining cell viability allowed confirmation of earlier microautoradiographic studies (e.g., Hoppe, 1976) which demonstrated that many of these nonculturable cells are indeed viable and able to actively metabolize. Such studies led to the further realization that some bacteria, in response to certain environmental stresses, may lose the ability to grow on media on which they are routinely cultured, while remaining viable. This state is of considerable interest to our understanding of microbial ecology. It is of special concern when considering release into the environment of genetically engineered microorganisms, and for those indicator bacteria (e.g., coliforms) and human pathogens which enter this nonculturable state and are thus not detectable through routine bacteriological procedures.

Evidence-Based Practices in Secondary Transition:

Abstract: A literature review was conducted to identify evidence-based practices in secondary transition using quality indicator checklists for experimental research. Practices were categorized by the Taxonomy for Transition Programming. Overall, 32 secondary transition evidence-based practices were identified. Two practices had a strong level of evidence, 28 had a moderate level of evidence, and 2 had a potential level of evidence. The majority of practices represented instruction of skills within the category of Student Development. No evidence-based practices were identified in the category of Interagency Collaboration. Findings provide practitioners with a set of evidence-based practices for improving transition services and researchers with an agenda for conducting future research.