PrimeTimes Newsletter, Fall 2010

PrimeTimes is the newsletter of the Office of Lifespan Studies in the College of Science at Coastal Carolina University

The Chanticleer, 2010-04-05

The editorially independent student produced weekly newspaper of Coastal Carolina University.https://digitalcommons.coastal.edu/chanticleer/1549/thumbnail.jp

PrimeTimes Newsletter, Spring 2010

PrimeTimes is the newsletter of the Office of Lifespan Studies in the College of Science at Coastal Carolina University

Catalytic Decomposition of Peroxynitrite and Superoxide by Nafion Films Modified with Iron and Manganese Porphyrin

Nafion films alone and modified with inert electrolytes and metalloporphyrins were tested in their effectiveness of decomposition of aqueous peroxynitrite (PN) and superoxide. Films that were modified with a cationic manganese porphyrin, which has been shown to be responsible for catalytic decomposition of superoxide ion, were found to be most effective. Peroxynitrite was generated in solution by the decomposition of 3-morpholinosydnonimime (SIN-1) that generates nitric oxide and superoxide ion, which rapidly combine to form peroxynitrite. The tyrosine analogue 4-hydroxyphenylacetic (4-HPA) was used to trap the PN in pH 7.00 PBS buffer and was its nitrated product was detected by observing the change in visible absorbance at pH 10. The Nafion films modified with manganese porphyrin were active in superoxide quenching and the therefore blocking of peroxynitrite formation throughout a five week testing period. These experiments offer new strategies for disrupting superoxide and peroxynitrite in vivo

Net Metering and Interconnection Standards for Santee Cooper and Three Investor-Owned Utility Companies in South Carolina

Net metering and interconnection standards are designed to allow private residential and non-residential electric utility customers to pursue generating some of their own electricity through renewable sources such as solar, wind, and geothermal power. Net metering allows customers to use their own electrical generation to offset their consumption over a billing period by allowing their electric meters to run backwards when they generate electricity in excess of their demand (SC Energy Office, vi). The interconnection standards govern the technical and procedural process by which an electric customer connects an electric-generating system to the electrical grid of their utility company (SC Energy Office, v)

Seasonal Residency and Movement Patterns of Blacktip Sharks, Carcharhinus limbatus, in a South Carolina Estuary

Usage of a coastal estuary in South Carolina by blacktip sharks, Carcharhinus limbatus, was examined using acoustic telemetry from June to September 2009. Acoustic monitoring data were used to define residency and movement patterns in North Santee Estuary, SC. Sharks were detected for 1-45 days with individuals frequently moving in and out of the monitored area. Monitored sharks showed a great deal of variability in residency, with sharks utilizing the estuary for 1-39 consecutive days. The majority of incursions into the estuary lasted less than 12 hours, but sharks did remain in the estuary continuously for up to 173 hours. Sharks swimming direction was strongly correlated with tidal stage. Sharks entered the area on incoming and high tides, and exited on outgoing and low tides. No preference towards time of day was found for area use, with tagged sharks spending a proportionate period of time in the study site during day and night. Sharks also preferred to enter and exit the area during the day, but only exits showed significant differences. Swimming speeds of blacktip sharks using passive acoustic telemetry found that maximum swimming speed was near that of other observed swimming speeds of similarly sized carcharhinid sharks, and was found to be an acceptable method for estimating swimming speed in the wild when general swimming direction and path are known. The movement and residence patterns of blacktip sharks suggest that individuals range from transient users to near-seasonal residents in the estuary

An Examination of Soil Surface Temperatures in High Marsh Plant Habitats at Waties Island, SC

Salt marshes serve several important functions; as barrier habitats between the terrestrial and marine environment, sources of important nutrients to estuarine and oceanic organisms and unique habitat for many species of plants and animals (Levine et al., 1998; Mitsch and Gosselink, 2000). These ecosystems are highly zonated and express patchy plant and animal distributions. While much of this distribution is attributed to variation in stressors (e.g. salinity and water availability) it is still not entirely understood. In an area that is likely to be effected by global climate change (through rising air temperature and sea level) as well as continuous human development, it is critical to understand the small scale processes within a salt marsh to determine what effects changes to these habitats tnay have on the life and functions within the salt marsh. This study investigated surface sediment temperatures of several plant habitats (Juncus roemerianus, Salicornia spp., Spartina patens, Salt Pan, Mix and Random) and factors controlling those temperatures within the high marsh of Waties Island, SC using hourly data from temperature data loggers at 30 sites in the mid high marsh region. Tidal effects were determined by looking at three elevations of the Mix habitat with an additional 10 sites (5 each in the high high marsh and low high marsh). Manipulative experiments were used to determine the effects of shading and evapotranspiration within each habitat in the mid high marsh region

Relationship Between Macroinvertebrate Assemblage Structure and Ecosystem Function in Two Coastal Plain Blackwater Streams

Ecosystem structure is often used to indicate ecosystem function in studies of stream integrity because structure is usually easier to measure. Whether structure can be substituted for function, however, is seldom assessed. I used ecosystem structural measures (i.e., % of total benthic macroinvertebrates classified functionally as shredders and fungal biomass on leaves) to predict ecosystem function (i.e., leaf breakdown rate). Structural and functional parameters were measured at four sites in each of two forested blackwater streams near Myrtle Beach, SC. Pre-weighed red maple (Acer rubrum) leaves in coarse-mesh bags were sampled monthly from December 2008 to April 2009. Macroinvertebrates colonizing litter bags and fungal biomass (from ergosterol) associated with leaves were quantified. Benthic macroinvertebrates were sampled once using protocols developed for calculating the Coastal Plain-Macroinvertebrate Index and additional leaves were sampled for fungal biomass in each site in March 2009. Despite most sites being acidic (pH ranged from 4.12 to 7.96) and having low dissolved oxygen concentrations (range: 0.82 to 6.03 mg/L), I detected considerable microbial biomass. Leaf breakdown rates varied significantly among sites, with k values ranging from 0.004 to 0.017 d-1. Breakdown rates were not significantly related to mean fungal biomass found in litterbags or to maximum fungal biomass. Percent shredders based on biomass collected during the CPMI sampling and from litterbags were significantly positively related to breakdown rates while percent shredders based on abundance was not. Mean dissolved oxygen across sampling dates and during CPMI sampling was significantly related to breakdown rates. Results of this study suggest that structural metrics of mean dissolved oxygen and percent shredders based on biomass could be used as indicators in Coastal Plain streams. This study also emphasizes the need to use structural metrics specific to the study region and its habitat characteristics when evaluating ecosystem functioning