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ItemPartial Characterization of PF13_0027: A Putative Phosphatase of Plasmodium Falciparum(2013) Campbell, ChristopherSignal transduction and stage-specific gene expression are essential components of Plasmodium falciparum development. In this study, the putative phosphatase PF13_0027 is investigated as a critical component of intraerythrocytic development contributing to maturation of the late trophozoite. This putative phosphatase was identified during the course of a large-scale insertional mutagenesis project by insertion of the piggyBac (pB) element, containing a human dihydrofolate reductase (hDHFR) drug selection cassette into the open reading frame (ORF) preventing expression and attenuating parasite development. PF13_0027 codes for a protein with a rhodanese (RHD) and dual specificity phosphatase (DUSP) in a tandem arrangement typically identified with mitogen-activated protein kinase (MAPK) phosphatases (MKP). Despite numerous INDELs, the tertiary structure is conserved when compared to the solved structures of MKP homologs. The expression profile reveals transcripts at all stages of the blood cycle with a highest relative abundance in the late trophozoite. Restoration of the phenotype was achieved through genetic complementation using the complete PF13_0027 open reading frame (ORF) under the control of its endogenous promoter. A homology model of PF13_0027 was developed for structural analysis and evaluated using in silico high-throughput screening (HTS) to identify antimalarial compounds with predicted affinity to the active site and used to challenge parasites in vitro. This study reveals that PF13_0027 is a vital component of asexual development and a potential target for a new class of antimalarial compounds targeting phosphorylation pathways in P. falciparum. Discovery of the functional role of this unknown ORF provides additional insight into the importance of MAPK signaling in P. falciparum. ItemThe Effects of Religiosity on Parent-Adolescent Communication about Sex and Sexuality: A Multiple Regression(2017) Robinson, MarlonMost studies on parental religiosity have focused on specific adolescent sexual behaviors (i.e. sexual initiation), family cohesion, greater supervision, and higher moral expectation while parent-adolescent communication about sexual matters remains understudied. The purpose of this study was to examine the relative influence of parent variables such as relation, education level, communication style (degree of openness, extent of problems), and religiosity (public, private) on sex communication and the age at which parents began conversations about sexual matters. A sample of 170 parents and caregivers from the Continental United States who had at least one adolescent 13-18 years old completed questions on demographics, religiosity, Parent/Adolescent Communication Scale (PACS), age of initial conversation about sexual matters, and The Sexual Communication Scale (SCS). Results indicated most parents initiated conversations about sexual matters by age 12. A multiple regression was used to investigate the influence of the parental variables on sex communication and the age at which parents began conversations about sexual matters. The results of the multiple regression analysis on the influence of the predictor variables on age of the initial conversation about sexual matters indicated that parental education level and degree of openness were negatively related to the age of initial parental conversation about sexual matters. A second multiple regression was conducted with the same predictor variables to determine if they had an influence on communication about sexual matters. These variables had no significant influence on conversations about sexual matters. In both multiple regression analyses, religiosity was not significantly associated with the age at which parents began conversations about sexual matters and sex communication in general. Discussion focused on implications for parents, educators, therapists, and future research. ItemGender Disparity in Studying Chemistry(2021) Semerzier, CarloThis applied dissertation was designed to determine if there is a difference between students’ gender, ethnicity, and age and their performance in General Chemistry I at a Christian University in Florida. Many scientific studies reveal the existence of a gender performance gap in chemistry: women mostly underperform men. Certain factors reported by researchers and cited in this study that might contribute to this gap include self-efficacy, math ability, prior conceptual knowledge in chemistry, attitude toward chemistry, spatial ability, discrimination, learning styles, and exam types. This quantitative research study used retrospective data from 113 students from eight sections (2016-2019) of a General Chemistry I course. Each participant was enrolled in one of the eight sections and was taught by the same instructor. The final course grade was the dependent numeric variable, and gender, ethnicity, and age were the independent categorical variables. For all statistical analyses, student's t-test and the analysis of variance (ANOVA) were used. Data analysis revealed a significant difference in the final course grade between gender who study General Chemistry 1 in higher education. There was no significant difference in final course grades between the ages categories: younger than 21 years old and 21 years old and older. Additionally, there was no significant difference in final course grades between ethnicities. The findings suggest that female students underperformed their male counterparts in general chemistry I in higher education, and the final course grade in General Chemistry I was not affected by students’ age and ethnicities.