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After-School STEM Programs and the Impact on 21st Century Skill Development
No full textThis thesis used data collected from an online survey of 22 Code Ninjas employees in the United States to determine the impact of an after-school science, technology, engineering, and mathematics (STEM) program on students’ development of 21st-century skills. This study’s findings indicated most owners and Center Directors agree social skills and creative thinking skills are improved through enrollment in an after-school program like Code Ninjas. More than half of the participants shared first-hand accounts of instances where students demonstrated 21st-century skills while working in the Code Ninjas program
The dose dependent effects of Pimavanserin on a modified rodent model of post-traumatic stress disorder
Get PDFPost-traumatic stress disorder (PTSD) is a persistent psychiatric disorder where patients develop symptoms from directly experiencing or witnessing traumatic events. The animal models are often used as preclinical studies for PTSD. Our research group previously found that the developed animal model of PTSD, which was composed of chronic and acute stress, successfully induced PTSD-like anxiety behaviors in the three behavioral measurements: elevated-plus maze, open field, and acoustic startle response. Additionally, the inverse antagonist drug Pimavanserin significantly reduced these fear-related behaviors in the animal model. In the current research, we examined the effects of each stressor, specifically the effect of social isolation, in addition to the replication of the effects of Pimavanserin on the animal model of PTSD, including the dose dependence of Pimavanserin. As a result, higher dose injections significantly reduced rats’ anxiety-level in the behavioral measures, while the smaller and no Pimavanserin injections did not change animals’ behaviors. In relation to the effect of social isolation, there was no significant difference between animals in the single housed group and pair housed group. These results strongly supported the role of 5-HT2A in our PTSD-animal model. Furthermore, from the results, it is highly expected that the 5-HT2A receptors’ inverse antagonists have positive therapeutic effects on PTSD patients
Investigating Various Stakeholders Perceptions of Strategies That May Be Used To Improve Attendance Among Secondary High School Students
Get PDFStudent attendance is one of the most important factors leading to a student’s achievement academically. Chronic absenteeism can lead to a variety of issues for a secondary high school student, including not graduating. Students who miss school on a regular and consistent basis are identified as being chronically absent. Graduation rates and dropout percentages among America’s high school students are negatively impacted by the number of school days they miss each year.
The purpose of this study was to investigate high school principals and assistant principals, teachers, and truancy officers’ perceptions of strategies that may be used to improve attendance among secondary school students who are at-risk for dropping out. This research study explored the significant percentages of students in the state of Texas who are at-risk for dropping out of high school each year, due to high rates of absenteeism.
Findings revealed administrators, teachers, and truancy officers involved parents in their efforts to increase attendance among students who are at risk through on-going communication and other various methods of exchange. Barriers were revealed, administrators, teachers, and truancy officers did not provide on-going communication for students parents who’s English is a second language. Parental involvement and incentives were deemed a top priority by administrators and teachers but solutions to engage parents of students that are socioeconomically disadvantaged was not addressed.
Recommended future studies should examine measures taken to communicate with at-risk students with parents whose English is a second language and greater insight into what specific incentives are most effective for the socioeconomically disadvantaged population of students and parents. The findings would provide districts with a better understanding the needs to improve student attendance among secondary high school students.
Foraging Ecology of Bottlenose Dolphins (Tursiops Truncatus) in Galveston Bay, Texas
Get PDFThe overall goal of this research was to develop a better understanding of the trophic ecology of the Galveston Bay common bottlenose dolphin (Tursiops truncatus) stock that would provide critical data needed to manage this species. The specific objectives of this study were to: (1) estimate areas used by dolphins for foraging, (2) estimate factors contributing to foraging behaviors of dolphins, and (3) estimate proportions of different prey consumed by bottlenose dolphins in Galveston Bay. From 2015-2017, two survey methods (behavioral data from photo-identification surveys and stable isotope data from biopsy surveys) were used for objective one and two, while stable isotope (δ13C and δ15N) mixing models were used for objective three. Dolphins were observed foraging for 62.3% of all photo-ID sightings. Dolphins were observed foraging most often in the channel (52.3%), followed by open bay (41.4%), and nearshore (6.3%) but there is no evidence that the odds of observing foraging behavior was different between the habitats. For the sightings where foraging behavior was observed, 68.7% of the time a trawler was present. It is estimated that when approaching a shrimp trawler during a survey, the probability of observing dolphins patrolling is 60.8% of the time (95% CI: 55.6% to 100.0% , one-sided, one-sample porportion test, p-value <0.05). Foraging significantly decreased as time passed throughout the day in sightings from 2015-2017 (beta regression: pseudo R2= 0.8726, p-value <0.05). Potential prey of dolphins were collected in 2015 and 2016 for stable isotope analysis. Data from those sampling events and select nekton from Barcenas (2013) were used to model proportions of prey consumed by dolphins using A Bayesian isotope mixing model, Stable Isotope Analysis in R (MixSIAR version 3.1.10). Ward’s hierarchical cluster analysis was used to group 19 nekton species into six groups based on their mean C and N isotopic values. Overall, group six which contained only one species, White Mullet (Mugil curema), was estimated to contribute to the highest proportion of nekton prey consumed by dolphins (median: 25.3%) based on MixSIAR analyses. The second highest proportion consumed by dolphins overall was group two (Atlantic Brief Squid [Lolliguncula brevis], Hardhead Catfish [Ariopsis felis], and Striped Mullet [Mugil cephalus]) at 21.0%. There was a significant difference between the δ15N (‰) values in Upper Galveston Bay (UGB) and Lower Galveston Bay (LGB) (Wilcoxon Rank Sum Test, W=105.5, p-value≤0.05). This difference may suggest that dolphins in UGB and LGB are foraging on different prey or may support the notion that the upper portions of the bay are more heavily influenced of elevated anthropogenically produced δ15N (‰). This research contributes to baseline data that can be used for further analysis in future studies. The results from the stable isotope analysis may be used in combination with mercury and organochlorine contaminant analysis to examine trophic level biomagnification in the Galveston Bay ecosystem
Inventory of Shuttle Carrier Aircraft Documents
No full textThese documents were collected by the Engineering Analysis Division, Aerodynamics Branch, which was the JSC group responsible for studying the Shuttle ferry concepts. The documents track the studies done by Boeing, Lockheed, Rockwell, JSC, Langley, & McDonnell Douglas which contributed to the choice of the modified Boeing 747 as the carrier of the Shuttle Orbiter for both ALT (Approach & Landing Tests) and ferry flights. The Boeing Reports are organized chronologically and followed by wind tunnel reports, Rockwell reports, and Lockheed reports. At the end of the run are miscellaneous subject files organized by folder dates and consisting of presentation material, correspondence, meeting minutes, and reports. The bulk of the documents were produced between 1974 and 1976
Inventory of Phase C/D RFP and Related Documents
No full textThese documents were culled from Procurement files sent from the vault in Building 1. They consist of the Phase C/D Request for Proposal, drafts, amendments, and attachments along with related correspondence and miscellaneousdocumentation. The documents run from 1971 to mid 1972. They are arranged with RFP documents first, followed by related miscellaneous documents and correspondence. The latter are arranged chronologically
Inventory of STS-61-C Mission Documents
No full textThis subseries is a collection of documents related to STS-61-C and arranged in chronological order. They include Mission Reports, Flight Requirement Documents, Mission Reviews and Press Information
Classification of fMRI Brain Activation Maps by Using Space Filling Curves
Get PDFFunctional magnetic resonance imaging or functional MRI (fMRI) is a brain imaging technique which is used to measure brain activity by detecting changes associated with the blood flow and oxygenation, which are indirect measures of neural activity. When participants perform a task and/or have some stimuli during their fMRI scans, fMRI data helps us to obtain brain activation maps, which have three spatial dimensions (3D). 3D activation maps need to be converted (ordered, or vectorized) to 1D vectors for further analyses such as localization and classification of activations and/or participants. Traditionally, the 3D to 1D conversion has been done using linear ordering, which loses most of the information about the spatial structure of the brain. Instead, one can use space-filling curves (SFC) for vectorization, such as a 3D Hilbert curve, which can better preserve the structure of the brain; however, it is still far from being optimal. Finding an SFC which is adaptive to human brain can better preserve the structure of the human brain in 3D-to-1D ordering. The problem of finding an adaptive optimal SFC is inherently a modified traveling salesman problem (TSP).
In this work, we obtained an approximation of the SFC practically using a heuristic solution to the modified TSP. We used completely de-identified fMRI brain activation maps from schizophrenia fMRI experiment participants. We first applied a Hilbert SFC to obtain features and apply deep learning and other machine learning algorithms to classify participants from their brain activation maps and to fine-tune algorithm parameters. We also used an approximation of the optimal SFC using a TSP heuristic, converted the brain maps to 1D and obtained features for classification. The classification based on the heuristic approximations of adaptive SFC’s orderings yielded comparable or better classification accuracies than those of linear ordering and Hilbert ordering
