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The Effect of Ethanol on Neural Crest Cells and Cardiac Innervation
Get PDFFetal alcohol syndrome (FAS) occurs in 0.2 to 1.5 per 1,000 infants born. FAS results in symptoms such as abnormal craniofacial features, impaired cognitive abilities and cardiovascular defects. However, the impact of prenatal ethanol exposure on the neural crest cells responsible for cardiac innervation remains understudied. This study investigates the effect of variable timing of ethanol treatment on cardiac and trunk neural crest cells and the subsequent impact on cardiac innervation. Early ethanol treatment led to decreased apoptosis in the neural tube and increased apoptosis in the migratory pathway towards the outflow tract in the cardiac neural crest. Early ethanol exposure also decreased cardiac neural crest cell migration in the cardiac circumpharyngeal ridge and increased neural crest cell migration in the pharyngeal arches. Later ethanol exposure resulted in increased apoptosis in the trunk neural crest region of the neural tube and decreased neuronal branching on the anterior base of the outflow tract. Later ethanol exposure also substantially increased migration in the circumpharyngeal ridge in the trunk neural crest and slightly increased migration in the cardiac neural crest region of the circumpharyngeal ridge. These findings suggest that early ethanol exposure may lead to a lack of selection for the proper neural crest cells reaching the heart necessary for survival, and that later alcohol treatment shows a similar impairment in the selection process for neural crest arriving to the heart, resulting in reduced cardiac neuron branching. Further studies can determine how cardiac innervation is influenced by varying concentrations of neural crest arriving to the heart and how apoptosis shapes the directionality and specification of the migratory pathway
Two novel proteins, TtpB2 and TtpD2, are essential for iron transport in the TonB2 system of Vibrio vulnificus
Get PDFIn gram‐negative bacteria, energy‐dependent active transport of iron‐bound sub‐ strates across the outer membrane is achieved through the TonB systems of proteins. Three TonB systems have been identified in the human pathogen Vibrio vulnificus. The TonB1 system contains three proteins: TonB1, ExbB1, and ExbD1. Both the TonB2 and TonB3 systems have been shown to also contain a fourth protein, TtpC2 and TtpC3, respectively. Here, we report and begin to characterize two additional proteins in the TonB2 and TonB3 systems: TtpB and TtpD. Both TtpB2 and TtpD2 are absolutely required for the function of the TonB2 system in V. vulnificus. However, although both TtpB3 and TtpD3 in the TonB3 system are related to the proteins in the TonB2 system, neither are active in iron transport. All six protein components of the TonB2 system—TonB2, ExbB2, ExbD2, TtpB2, TtpC2, and TtpD2—are essential for the uptake of both endogenously produced iron‐bound siderophores and exog‐ enous siderophores produced from other organisms. Through complementation, we have shown that V. vulnificus is capable of using different TtpD2 proteins from other Vibrio species to bring in multiple siderophores. In contrast, we also demonstrate that TtpB2 must come from V. vulnificus, and not other species within the genus, to complement mutations in the TonB2 system
Understanding the Self-Efficacy of Assistant Principals in an Urban School Division: Patterns, Trends, and Challenges to Be Mastered
Get PDFThis study sought to understand the perceived levels of managerial, instructional, and moral self-efficacy of assistant principals (N = 101) serving in an urban Albertan school jurisdiction. Levels of self-efficacy (Bandura, 1986) were measured using the Principal Sense of Efficacy Scale (PSES) (Tschannen-Moran & Gareis, 2004). Additionally, the instructional leadership indicators of the Alberta Leader Quality Standard (LQS) (Alberta Education, 2019) were measured for levels of importance and perceived level of proficiency by participants. Finally, assistant principals were asked to indicate if they held aspirations for principalship, provide rationale for their response, and express what professional learning experiences might be necessary to become a principal.
This study contributed to the extant literature pertaining to building and realizing greater levels of self-efficacy in assistant principals, a population which has been chronically underserved and underrepresented in the literature. Existing research has suggested that more time and attention is needed in the domain of instructional leadership which is often overlooked due to the managerial demands of an administrative role that has not been fully defined, appreciated, or supported.
The first phase of this study analyzed the PSES scores across three subscales and found that participants scored highest in efficacy for moral leadership, second highest in instructional, and lowest in managerial. These results were disaggregated by various demographic factors and suggested that females (n = 70) had the highest scores in all subscales compared to males (n = 31). The second phase of the research design asked participants to rate levels of importance and proficiency on the nine
indicators inherent to the LQS instructional leadership domain. In both importance and proficiency, it was males who scored higher than females. A very strong correlation of r =.93 was found between the level of importance and level of proficiency across all participants. Relationships between the PSES instructional subscale and the LQS indicators revealed a stronger relationship for females r =.48 than males (r =.40).
Finally, 33% of participants indicated aspirations to pursue principalship whereas 21% did not and the remainder were undecided. Ongoing long-term mentorship, more mastery learning experiences in instructional leadership and leading the operations of a learning community were among the top responses from the participants as to what is needed to further their professional development.
This descriptive study sought to understand the landscape of assistant principals in an urban setting and how their self-efficacy scores and interaction with leadership standards (instructional leadership) might provide the school jurisdiction with insights on how to enhance existing assistant principal leadership programming
Self-Discovery Through Language Learning: From Spanish 101 to Immigration Law
No full textThis presentation is part of the Sojourner Scholars program. Students will present portions of their portfolios which document how they have achieved the global and intercultural learning outcomes (GILOs) of the program
Blount International - Chainshot Visualization
No full textThe UP Chainshot Visualization capstone team worked with Blount International to design and build a z-type schlieren optical system to visualize air density gradients surrounding a chainshot projectile. Chainshot occurs when a chainsaw blade breaks and fires a projectile, causing shockwaves, which can be visualized by a camera using the optical system. Blount will use data from this optical system to further understand the behavior of a chainshot event.https://pilotscholars.up.edu/egr_project/1032/thumbnail.jp