Arts and Sciences 3MT Competition

Nitrogen (N) is an essential nutrient that plants need in large amounts for growth and development. It is required for the synthesis of amino acids, proteins, nucleic acids and many essential metabolites. In industrial countries, extensive N fertilizer use guarantees high crop yield. However, this level of fertilizer production and application is not sustainable because of costly high-energy inputs and negative effects on human health and the environment through greenhouse gas emissions and water pollution. In developing countries, on the other hand, access to N fertilizer is limited and insufficient N nutrition results in low crop productivity and ultimately in reduced food supply. A solution to these issues could be the production of crops that use N more efficiently and require less N fertilizer. One potential strategy for improving N use efficiency in plants is to regulate N allocation to specific plant organs for optimum growth.

In general, partitioning of N within plants occurs in the form of amino acids. Transport proteins in cellular membranes are necessary to move amino acids into cells and over long distances. Our lab has identified transporters that play central roles in allocation of amino acids to growing plant organs. We found that manipulation of amino acid transporter expression in Arabidopsis and pea plants results in improved seed yields under high N conditions. In this study, it is hypothesized that the transgenic Arabidopsis and pea plants continue to outperform non-transgenic plants under reduced N fertilization, and that alteration of N transport processes leads to more efficient N use. The transgenic lines were grown under a deficient, limiting or sufficient N fertilization regime, and physiological, biochemical and molecular analyses were used to determine plant N use efficiency and nutritional status. Results showed that the transgenic plants display increased N use efficiency under all N conditions tested. Additionally, Arabidopsis and pea plants with modified N transport required half the amount of N to produce as many fruits and seeds as their non-transgenic counterparts. Overall, it was demonstrated that altering amino acid allocation presents an effective strategy to improve plant yields, while reducing the input of N fertilizer.

High trait anxiety is associated with vulnerability to biases when making decisions with uncertain outcomes, i.e., risky decisions. When risk information is provided (descriptive risk) trait anxious individuals’ exhibit increased decision bias, leading to suboptimal choices. In contrast, when risk information must be learned through previous decision consequences (experiential risk) the impact of trait anxiety is not well understood. The present study examined how experience with decision outcomes reduces framing bias in risky decision making, and whether people high in trait anxiety may benefit from experience with decision outcomes. Participants completed a decision making task in which repeated choices were made between a sure option (gain or loss), and a risky gamble option. In this task, framing bias appears as a preference for the gamble over the sure loss and preference for the sure gain over the gamble. Advantageous decision making requires overcoming the framing bias through experience with choice outcomes. Affective reactions to choice outcomes were
measured using skin conductance response. Results showed that high trait anxiety individuals were more susceptible to framing bias, but were capable of reducing the impact of bias and improving advantageous choices over time. Skin conductance response results revealed that vulnerability to framing bias with trait anxiety was attributable to stronger affective reactions to sure gain outcomes. Interestingly, when trait anxious individuals were given more time to consider their choice, they made less-biased decisions, similar to their non-anxious counterparts. This suggests trait anxious persons are capable of overcoming affect-driven bias through the experience of choice outcomes, thereby optimizing their decision making over time.

Objective: This research sought to test the measurement invariance of the Birth Satisfaction Scale-Revised (BSS-R) and compare birth satisfaction levels across United States (US) and United Kingdom (UK) samples. Background: Recent healthcare advances around the world emphasize exceptional health care service that in turn leads to greater patient satisfaction. Because satisfaction is one of the most widely reported outcome measures of quality of care, an evaluation of birth satisfaction can be considered a direct measure of maternal care quality. Additionally, testing the measurement invariance of the BSS-R can shed light on the usefulness and accuracy of the scale within and across cultures. Method: Using Confirmatory Factor Analysis (CFA), data previously collected from 409 mothers (181 US mothers; 228 UK mothers) were used to examine the multiple-group measurement invariance of the BSS-R model across US and UK samples. Results: A correlated factors BSS-R demonstrated partial measurement invariance. US mothers had significantly lower birth satisfaction levels on the three BSS-R subscales of quality of care, stress experienced during labor, and women’s attributes. Conclusions: The BSS-R is a robust tool that can be used to reliably measure women’s birth satisfaction within and across the US and UK. However, the cultural differences revealed in this research strongly suggest that higher caesarean rates, along with costly practices, higher rates of hospital births, and under-utilization of midwives are negatively influencing women’s birth satisfaction in the US.

This dissertation examines the use of supporting evidence in undergraduate writing to track epistemological development in the first two years of college. The central study builds on fifty years of personal epistemology research (e.g. Perry, 1968; Belenky et al., 1986; Baxter Magolda, 2002; Baxter Magolda & King, 2012). Much of this research has found that individuals enter college grounded in outsider-based epistemologies, believing that knowledge is discovered by experts (e.g. scientists) and communicated to the masses through them. Over time, college students begin to view knowledge as contextualized by the knower’s prior experiences. However, these studies rely heavily on interviews, a method that is not only time consuming but prone to error as interviewees (consciously or not) shape responses to fit the interviewer’s purpose.

Rather than rely on interviews, this study uses writing produced independent of this study from 80 college students—ranging from pre-enrollment writing exams through WSU’s mid-career writing assessment—to develop a method for performing this research more efficiently on larger scales and to test whether the prevailing beliefs about epistemological development hold true outside the interview setting. The results of this study will better inform post-secondary educational practice, as it examines epistemological development independent from major (e.g. diSessa, 1993; Chi, 2008) and on a scale larger than an individual semester (e.g. Nowacek, 2011).

In polarized America, the two political parties own different words, and campaigns tend to use the words owned by their party and avoid the words owned by the other party. This partisan word ownership is observable in issue areas, but it also applies to – and is more commonly found in – non-issue areas, including the words referring to ideological labels (e.g., “I am proudly conservative and he is liberal!”) and particular political actors (i.e., attacking members of the out-group). In this research, I take both theory-driven and data-driven approaches to examine the partisan use of words in campaign rhetoric. My data consist of 2,349 emails sent by candidates running in 2014 U.S. Senate races. As the partisan rhetorical differences in issue emphasis are only a small part of the big picture, it seems unlikely for the campaign rhetoric to help citizens learn where each party stands on the issues of the day.