A Spectrophotofluorometric Analysis of Serum Vitamin A Levels in a Defined Population

The objectives of this thesis were to examine serum vitamin A levels in two defined populations. The method of analysis was a spectrophotofluorometric technique with a correction formula to account for interfering fluorescence from an identified carotenoid phytofluene (37). The first population were infants at time of delivery. Infants were divided into two groups depending upon length of gestation. A premature group was identified as having a length of gestation of less than 36 weeks. Term infants were defined as 36 weeks or greater. The mean value of serum vitamin A of eight premature infants was 10.5 μg/100ml (S.E.M.+.78). The mean value of 54 term infants was 22.5 μg/100ml (S.E.M.+.96). Comparing these two groups results in a p value of The second population studied were patients undergoing periodontal surgery. The purpose was to monitor serum vitamin A levels before and after surgery. The results are inconclusive due to the small number of samples. In this thesis the results are discussed and recommendations are made for future projects in this area

Investigation of possible causes for human-performance degradation during microgravity flight

The results of the first year of a three year study of the effects of microgravity on human performance are given. Test results show support for the hypothesis that the effects of microgravity can be studied indirectly on Earth by measuring performance in an altered gravitational field. The hypothesis was that an altered gravitational field could disrupt performance on previously automated behaviors if gravity was a critical part of the stimulus complex controlling those behaviors. In addition, it was proposed that performance on secondary cognitive tasks would also degrade, especially if the subject was provided feedback about degradation on the previously automated task. In the initial experimental test of these hypotheses, there was little statistical support. However, when subjects were categorized as high or low in automated behavior, results for the former group supported the hypotheses. The predicted interaction between body orientation and level of workload in their joint effect on performance in the secondary cognitive task was significant for the group high in automatized behavior and receiving feedback, but no such interventions were found for the group high in automatized behavior but not receiving feedback, or the group low in automatized behavior

Jaw Rotation in Dysarthria Measured With a Single Electromagnetic Articulography Sensor

Purpose This study evaluated a novel method for characterizing jaw rotation using orientation data from a single electromagnetic articulography sensor. This method was optimized for clinical application, and a preliminary examination of clinical feasibility and value was undertaken. Method The computational adequacy of the single-sensor orientation method was evaluated through comparisons of jaw-rotation histories calculated from dual-sensor positional data for 16 typical talkers. The clinical feasibility and potential value of single-sensor jaw rotation were assessed through comparisons of 7 talkers with dysarthria and 19 typical talkers in connected speech. Results The single-sensor orientation method allowed faster and safer participant preparation, required lower data-acquisition costs, and generated less high-frequency artifact than the dual-sensor positional approach. All talkers with dysarthria, regardless of severity, demonstrated jaw-rotation histories with more numerous changes in movement direction and reduced smoothness compared with typical talkers. Conclusions Results suggest that the single-sensor orientation method for calculating jaw rotation during speech is clinically feasible. Given the preliminary nature of this study and the small participant pool, the clinical value of such measures remains an open question. Further work must address the potential confound of reduced speaking rate on movement smoothness

The Civil Rights Movement: What Progress Has Been Made Since The 1950s?

The study of United States history, Post Civil War Reconstruction and the emerging Jim Crow Era in particular, brings into sharp focus the great divide – between races and ideologies. Stories of inequality, brutality, struggle and hardship abound, and students, researchers, and educators continue to examine and explore the many implications of the “house divided.” The Supreme Court, Federal Government, and general society, especially in the southern states, launched a systematic campaign of regression and oppression that would span decades and lead to the modern Civil Rights Movement in the 1950’s. This thesis project examines and uncovers an era of history with a specific focus on race relations in America. Discussion ranges from legal battles, Plessy v. Ferguson and Brown v. the Board of Education, to military and social programs and initiatives, which highlight the strained relationship between whites and blacks in America. As it examines this section of history it considers this simple question -- what progress has been made since the Civil Rights Movement of the 1950’s? The project concludes with a short application to current classroom efforts to “connect” students to history through personal observation and experience

The Reading Span Test and its predictive power for reading comprehension among young and old adults

Although many researchers appear to agree on the usefulness of both simple and complex span tasks, many disagree on the specifics of how or why they measure working memory. The following paper considers competing theories of the relationship between working memory tasks and higher order cognitive function. Consideration is given to simple and complex measures of working memory, various theories about them, and theories based on research within the cognitive aging domain. Subsequent discussion reports the findings from a new study aimed at resolving disagreements about the relationship between lower and higher level cognitive abilities in college-age and older adults

U.S. Meat Demand: Household Dynamics and Media Information Impacts

This article uses national, quarterly data to examine U.S. meat demand using the Rotterdam model. We investigate the effect of multiple information indices linking different health concerns with diet, changes in household dynamics, and meat recall information. Medical journal articles linking iron, zinc, and protein with health and diet increase beef and poultry demand, whereas articles dealing with fat, cholesterol, and diet concerns reduce beef demand. Increasing consumption of food away from home enhances pork and poultry demand while reducing beef demand. Combined, these results provide a more complete and current understanding of the impact of multiple information factors faced by U.S. consumers.Atkins diet, female workforce, food away from home, food safety, health concerns, meat recalls, U.S. meat demand, Demand and Price Analysis, Food Consumption/Nutrition/Food Safety, Livestock Production/Industries,

Elementary Students' Enjoyment and Social-Emotional Engagement in School: The Influence of Male and Female Teachers

The purpose of the study was to answer the main research question, which was “To what extent do male and female elementary teachers influence their students’ enjoyment and social-emotional engagement in school, from the perspective of grade 3-5 students?” The main research question was answered by focusing on three questions regarding enjoyment, engagement and implications for theory, practice and policy. The methodology of mixed methods was utilized in the research through the collection of quantitative data (survey) and qualitative data (focus group discussions). A total of 159 participants in grades 3-5 completed the survey and 29 participants in grades 3-5 took part in four separate focus group discussions. The findings indicated that some differences between male and female students may exist in students’ perceptions of male and female teachers’ influences of enjoyment and engagement. In particular, male students experienced more boredom in class than their female peers while more female students saw themselves as having a more caring relationship with their teachers. Students with male teachers identified more humour being used in the classroom as well as more self-efficacy than their peers with female teachers. Students perceived their teachers as more helpful as they moved from grade 3 to grade 5 and their trust in teachers also increased as they moved from grade 3 to grade 5. Overall, the majority of students perceived their teachers as wanting students to do their best in their school work. The findings from the research suggested implications for teacher practice, theory and policy. In particular, students identified trust, honesty and helpfulness as major influences of their enjoyment and engagement in school. Furthermore, students could benefit from a more equal exposure to male and female elementary teachers but more research needs to be done to fully understand the influence of male and female elementary teachers on students’ enjoyment and engagement in school

FACTORS AFFECTING FEEDER CATTLE PRICE DIFFERENTIALS

Feeder cattle prices are determined by the interaction of many factors. This study uses 1986 and 1987 Kansas feeder cattle auction data to investigate the impact of a wide variety of physical characteristics, many of which have not been used in previous studies on feeder cattle prices. Unlike previous studies, this analysis explicitly incorporates changes in feeder cattle market fundamentals during the data collection period and also allows price differentials to vary by sex and weight. Weight, weight-squared, lot size, lot size-squared, health, muscling, frame size, condition, fill, breed, presence of horns, and time of sale are significant factors affecting feeder cattle prices on any given day. Several physical traits also exhibit different seasonal price impacts.Demand and Price Analysis, Livestock Production/Industries,

Consumers Valuations and Choice Processes of Food Safety Enhancement Attributes: An International Study of Beef Consumers

Food safety concerns have had dramatic impacts on food and livestock markets in recent years. Here we examine consumer preferences for various beef food safety assurances. In particular, we evaluate the extent to which such preferences are heterogeneous within and across country-of-residence defined groups and examine the distributional nature of these preferences with respect to marginal improvements in food safety. We collected data from over 4,000 U.S., Canada, Japan, and Mexican consumers. Using mixed logit models we find that Japanese and Mexican consumers have WTP preferences that are nonlinear in the level of food safety risk reduction. Conversely, U.S .and Canadian consumers appear to possess linear preferences. These results suggest that optimal food safety investment strategies hinge critically upon consumer perception of actual food safety improvements, the distributional relationship describing the targeted consumer segment's tradeoff function between WTP premiums and risk reduction levels, and the cost structure of these investments.consumer beef preference, food safety, investment decision, mixed logit, willingness-to-pay, Demand and Price Analysis, Food Consumption/Nutrition/Food Safety,