Impact of urban runoff on phosphorus, nitrogen, and dissolved oxygen in a shallow subtropical lake

This research assessed the current conditions of water quality in a shallow subtropical lake, influenced by a highly developed urban environment. Specifically, the research focused on the dynamics of phosphorus, nitrogen, and dissolved oxygen, as well as the effects of stormwater runoff on lake water quality. Furthermore, the research quantified gross primary production, net primary production, and respiration in order to discern seasonal variation in lake metabolism. A water quality monitoring platform with multi-parameter probes was deployed in the center of University Lake on the Louisiana State University campus. A series of lake water quality parameters including dissolved oxygen (DO) concentration, temperature, pH, specific conductivity, and cyanobacteria were recorded continuously at a 15-min interval from July 2008 to October 2009. In addition, water samples were collected monthly as well as after major rain events during the study period to determine changes in total phosphorus (TP), nitrate (NO3-), nitrite (NO2-), and total Kjeldahl nitrogen (TKN) concentrations. Results show a monthly average concentration of 0.286 mg/L TP (min – max: 0.167 - 0.621 mg/L), 0.053 mg/L NO3-N (below detection – 0.24 mg/L), 0.045 mg/L NO2-N (below detection – 0.012 mg/L), and 2.5 mg/L TKN (below detection – 5.12 mg/L). Mean storm event loading of 28.1 kg (7.5 – 47.8 kg) caused an immediate increase in total phosphorus within the water column by 14.1%. This resulted in a mean TP lake concentration of 0.383 mg/L. A similar trend was observed in a lesser degree in NO3-N and TKN. Phosphorus loads in the lake were correlated with runoff volume (r2 = 0.71), suggesting runoff volume is the most important factor effecting lake TP concentration after a storm event. Analysis of metabolism rates found a mean annual gross primary productivity value of 4.41 g O2/m2/day, a mean annual net primary production value of 2.13 g O2/m2/day, and a mean annual respiration value of 5.90g O2/m2/day. Annually, 1610 g O2/m2 were produced while the annual sum of respiration was 2150 g O2/m2. Respiration rates were mostly equal to or greater than productivity rates throughout the year, indicating that this shallow subtropical urban lake was net heterotrophic throughout most of the year

Development and implementation of the verification process for the shuttle avionics system

The background of the shuttle avionics system design and the unique drivers associated with the redundant digital multiplexed data processing system are examined. With flight software pervading to the lowest elements of the flight critical subsystems, it was necessary to identify a unique and orderly approach of verifying the system as flight ready for STS-1. The approach and implementation plan is discussed, and both technical problems and management issues are dealt with

Understanding The Resilient Practices Of Journalists In The Face Of Hostile Sources: An Intersectional Approach

After former President Trump began calling the news media “the enemy of the American people,” many scholars and journalism practitioners worried about such anti-media’s trickle-down effect and how it would complicate work for local reporters. Given a growing need to pay attention to hostility toward journalists, this project sought to better understand the ways journalists experience the trickle-down effects of anti-media rhetoric in the form of hostile interactions with sources who vilify journalists; how women and journalists of color experience these effects to different, possibly heightened degrees; and how journalists are resilient in spite of these challenges. Drawing on 38 in-depth interviews with local journalists from across the United States, this project used the Communication Theory of Resilience (CTR) and the feminist theory of intersectionality to understand how journalists worked through hostility. Participants described five forms of hostility from sources and discussed their strategies for mitigating hostility. This project helps identify proactive, transformative resilience processes for working through hostility, such as the creations of journalistic teaching moments when journalists are confronted with hostile sources who buy-in to anti-media rhetoric and have a fundamental misunderstanding of the news. It also helps identify problematic, adaptive processes of resilience, such as the avoidance of potentially hostile sources who would utilize anti-media rhetoric, which perpetuates bias in the news. Many resilience processes are enabled or constrained by facets of the journalists’ identity, such that gender, race and age intersect to influence both the forms of hostility experienced by journalists and the ways they are able to be resilient in response to that hostility. Implications are discussed for journalists in both reporting and editor roles, and for journalism instructors

What is the Standard for State Standards? An Investigation of the State English Language Arts Standards of Colorado, Florida, Michigan, and New Hampshire

It is no wonder that the NCTE Elementary Section Steering Committee, comprising some of the most imaginative and introspective minds in the English language arts field, would eloquently encapsulate a pivotal issue in the nationwide standards dialogue. Within the group\u27s four page position statement is tucked this truth, Standards represent what we value (NCTE Elementary Section Steering Committee, 1996, p. 2). This brief declaration speaks to the enormous emotional investment which standards discussions involve and exemplifies the responsibility of creating standards