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A mentoring intervention using motivational interviewing for students on academic probation
No full textDuring the Spring 2021 semester, 19 freshmen students on academic probation were recruited for a MI mentoring intervention. The mentor completed 45 hours of MI training and reached MI proficiency prior to the start of the intervention. Participants provided survey feedback, qualitative responses regarding the meetings, self-reported goal attainment scaling (GAS) at three time points, and the Self-Efficacy for Learning Form (SELF; Zimmerman & Kitsantas, 2005) before the intervention and after the second meeting. Findings suggest the intervention had a high level of satisfaction from all participants. Mean scores from the self-reported GAS percentages increased across the intervention. Time fixed effects was not significant in the mixed model. A paired-sample t-test compared the difference in participant SELF scores across the intervention (N = 18). There was a significant increase in the self-efficacy for learning from before the intervention (M = 7.38, SD = 1.35) to after the second meeting (M = 8.63, SD = 1.36), t(17) = -3.76, p = .001. Mechanisms of relational aspects of MI and the outcomes were also explored and discussed. Current findings of the small-scale feasibility pilot provide support for the MI mentoring intervention project, calling for more sophisticated design, exploration of MI mechanisms
Structure of braid graphs in simply-laced Coxeter systems
No full textAny two reduced expressions for the same Coxeter group element are related by a sequence of commutation and braid moves. We say that two reduced expressions are braid equivalent if they are related via a sequence of braid moves,and the corresponding equivalence classes are called braid classes. Each braid class can be encoded in terms of a braid graph in a natural way. In this thesis, we study the structure of braid graphs in simply-laced Coxeter systems. In a recent
paper, Awik et al. proved that every reduced expression has a unique factorization as a product of so-called links, which in turn induces a decomposition of the braid graph into a box product of the braid graphs for each link factor. For a special class of links, called Fibonacci links, they showed that the corresponding braid graph is isomorphic to a Fibonacci cube graph. In this thesis, we prove that every Fibonacci cube occurs as the braid graph for a link in any simply-laced triangle-free Coxeter System whose corresponding braid graph contains the Coxeter graph of the Coxeter system of type ÇD
4 as a subgraph
Provenance analysis of siliciclastic beds of the Wilkins Peak member of the Lower Eocene Green River formation, Wyoming
No full textThe rock record of fluvial systems provides important information about provenance, sediment transport, fluvial architecture, and climate patterns throughout foreland basins by the way they respond to tectonics and greenhouse climates. Here we evaluate these parameters in the Eocene Wilkins Peak Member of the Green River Formation. There are nine laterally continuous alluvial siliciclastic intervals within the Wilkins Peak Member that record an alluvial distributary network that spanned across the floor of an ancient closed-lake system in southwest Wyoming during the Early Eocene. Samples collected from these alluvial intervals throughout the Bridger sub-basin and parts of the greater Green River Basin were analyzed using petrography, detrital zircon geochronology, and X-ray fluorescence to document the provenance of these beds and the distributary systems that fed them. Detrital zircon populations from the uppermost alluvial bed of the Wilkins Peak Member were split into chronofacies in order to connect sediment ages with adjacent source terrains and are shown to be dominated by Archean (4.0-1.9 Ga), Yavapai/Mazatzal (1.9-1.3 Ga), and Grenville ages (1.3-0.9 Ga), with minor contributions from Appalachian (900-350 Ma) and Cordilleran sources (350-0 Ma). XRF was used to measure the elemental concentrations of the sandstone and mudstone samples within the Wilkins Peak Member alluvial intervals. Principal component analysis of XRF results define three major chemofacies within the data set and were used in combination with sandstone petrography to understand mineral abundances within Wilkins Peak Member alluvial beds and reconstruct provenance of rivers that drained to Lake Gosiute. The first principal component is primarily controlled by the relative abundance of Rb, K, Al, Ti, Fe, and Zn, with samples of arkosic composition fed by the Aspen paleoriver coinciding with greater concentrations of these elements, whereas samples with greater Zr and Si concentrations have more quartzose compositions. Among the quartzose samples, sandstones derived from the Uinta Uplift and the Sevier fold and thrust belt can be differentiated by the second principal component, with greater concentrations of Mg, Mn, and Sr associated with more carbonate-rich compositions characteristic of fold and thrust belt-derived sandstones. Based on the data collected, two major paleorivers and a series of short steep streams on the north side of the Uinta Mountains drained into the depocenter of ancient Lake Gosiute during the deposition of the Wilkins Peak Member. Streams from the Uinta Mountains were the primary source for quartzose and conglomeratic detritus transported into the southern portion of the Bridger sub-basin throughout the WPM interval. Streams that were headed in the Sierra Madre, Gore, and Sawatch ranges joined streams that flowed down the eastern side of the Uinta Mountains and delivered arkosic sediment into the central and southeastern parts of the Bridger sub-basin and into the adjacent Washakie and Sand Wash sub-basins through the paleo Aspen River system. Streams that drained the Sevier fold-thrust belt were able to prograde out into the central parts of the Bridger sub-basin after the filling of the adjacent Fossil Basin and western Bridger sub-basin during the deposition of the lower Wilkins Peak Member, which underlies the marker beds. Sediment patterns within the Uinta Mountains streams and the paleo Aspen River system suggest that fine-grained siliciclastics were able to prograde out into the northern and central parts of the Bridger sub-basin after faulting along the Henrys-Fork Thrust fault ceased around the middle of Wilkins Peak Member time. Our results help define the dynamics of these river systems that drained into ancient Lake Gosiute during the deposition of the Wilkins Peak Member between 51.6-49.8 Ma and are necessary to understand the climate signals that are present within the Green River Early Eocene Climate Observatory Solvay Core, which contains one of the most complete and well-preserved archives of this ancient lake system
Quantification of heavy metals and metalloids in soil samples collected from grazing sites and streams around Cove, AZ
No full textThe focus of this work is to investigate potential uranium, vanadium, arsenic, and manganese contamination in soils because of previous mining activities in Cove. Topsoil samples from grazing sites were collected across Cove to assess its potential impact on the plants of these sites. Soil cores were collected near streambeds to assess the deposition of metals and metalloids on the soil by stream water. Following the demand for uranium after World War II, approximately 30 million tons of uranium ore was mined on the Navajo Nation until mining ceased in 1986. Cove, a region and community located in northeastern Arizona between the Lukachukai and Carrizo mountains, was one of the productive areas for extracting uranium ore. When the mining operations stopped, the mines were abandoned and left open without remediation. The ore and remaining mine waste were left exposed to the surrounding environment, causing concern for elevated levels of heavy metals and metalloids in the soil, plants, and water. Contaminated water running through Cove may introduce these contaminants to the soils and plants. Plants growing in contaminated soils may take up the excess metals and metalloids within them. Residents of Cove have livestock that graze on the plants on their land, so these contaminated plants can introduce metals and metalloids to their livestock, which in turn exposes the residents to the heavy metals and metalloids when they eat the animals. Since it begins with the soils, quantification of their metal and metalloid contents is important to identify where livestock may be at higher exposure.
Sample collection occurred on September 18-19, 2020, in a collaboration between Northern Arizona University and Diné College. All samples were processed, acid digested following EPA method 3051A, and analyzed for trace metal composition by either inductively coupled plasma – mass spectrometry (Thermo Fisher XSeries 2) or flame atomic absorption spectrometry (PerkinElmer AAnalyst 200 AA Spectrometer).
The key results were the concentrations of uranium, vanadium, arsenic, and manganese were well below residential soil screening limits set by the New Mexico Environment Department. The soils from the streams generally had a higher content of metals and metalloids than the soils from the grazing sites. The soils from the grazing sites generally had low concentrations, and, in general, the stream soils collected from one foot in depth had a higher metal and metalloid content than the soil from the surface
knowledge, use, and susceptibility of disposable pod devices and heated tobacco products in younger adults
No full textDisposable pod devices are the most recent type of electronic vaping products and are thought to be popular due to their availability in flavors. Recent FDA regulations have prohibited flavors in rechargeable pod devices but not disposable pod devices. The first purpose of the current study was to examine knowledge/awareness, use, the importance of flavors as a reason for use, and susceptibility to future use in a sample of younger adults in the United States. The current study also examined a heated tobacco product, specifically IQOS, which was recently approved by the Food and Drug Administration (FDA) for sale in the United States, regarding knowledge/awareness, harm perceptions, addictiveness perceptions, use, and susceptibility to future use. Data were collected in May of 2021 using a cross-sectional, non-random sample of 634 younger adults aged 18 to 35 registered on Amazon Mechanical Turk (MTurk). A substantial 26.98% of participants endorsed using a disposable pod device in their lifetime. Further, for past 30-day users of disposable pod devices, flavors were the primary reason noted for use (40.00%). Concerning IQOS, 29.13% of participants endorsed knowledge/awareness of the product and 24.60% endorsed IQOS lifetime use. These results were comparable to knowledge/awareness of a fictitious product called Hummingbird DLT, which 23.58% of participants endorsed knowledge/awareness of and 15.20% endorsed using in their lifetime. Further, approximately half of never users were classified as susceptible to future use to both the real IQOS device and the fictitious Hummingbird DLT. Finally, a significantly greater proportion of current smokers were susceptible to future IQOS use compared to never smokers. The current study contributes data relevant to researchers and public health professionals about disposable pod device use and the importance of flavors in the use of these devices, as well as important data about IQOS before it becomes nationally available in the United States
Polymer encapsulated DNA vaccine for sustained release
Get PDFTo improve the efficacy of single-dose vaccines, we have developed stabilizer-free poly lactic-co-glycolic acid (PLGA) nanoparticle formulations for use as drug and vaccine delivery systems capable of sustained-release. By removing commonly used toxic stabilizers such as poly vinyl alcohol (PVA), we were able to increase cellular viability, while maintaining stability of PLGA nanoparticles through optimization of PLGA composition. Nanoparticle stability is important to shelf life, vaccine encapsulation, and extended release for persistent immune activation. By altering charge, formulation temperature and protein addition, we have developed PLGA nanoparticles with tunable degradation over a one-to-two-month time periods. These improvements in nanoparticle delivery systems should provide for increased efficacy of single-dose vaccines by mimicking the prime-boost schedule currently used
Using self-efficacy and assessment to support computer science student success
No full textIn recent years, not only has there been a dramatic drop in the number of students enrolling in computer science courses, and attrition from computer science courses continues to be significant. Traditionally, computer programming courses have high failure rates, and as they tend to be core to computer science courses can be a roadblock for many students to their studies. But, is a computer science course really that difficult — or are there other barriers that negatively affect student progression? This work uses qualitative research following three aspects of computer science pedagogy to help students to improve their academic performance. These three aspects include:(1) How to manage students learning behavior --- Pair Programming and Self-Efficacy in CS1; (2) How to assess students learning and performance --- Logarithmic Rubric Scoring; (3) How to manage student behavior in the examination to make sure fairness --- The Geometry of Assessment. Results showed that this work could incrementally predict course performance, and it mediated the relationship between study behavior (self-efficacy or self-assessment) and both academic criteria. The computer science pedagogy behaviors in the research are a promising predictor of educational outcomes, and they may have usefulness in student course performance
Assaults and Mental Health Treatment in U.S. Jails
No full textInmates with serious mental illness (SMI) are significantly more likely than those without SMI to receive assault charges against staff or other inmates while they are in jail. Although mental health treatment has been shown to reduce the risk of violence in people with SMI in community samples, no research has distinguished the effectiveness of different types of mental health treatment in reducing the risk of jail-based assaults. The aim of the proposed study is to address this significant void in literature by investigating whether the risk of assaulting staff and other inmates in jail depends on mental health status and treatment. Using cross-sectional data collected in the National Inmate Survey of 2011-2012 from 52,926 adult jail inmates in the United States, logistic regression was used to investigate the likelihood of assault among mental health status groups: no indication of a mental illness, untreated SMI, SMI treated with medication, SMI treated with counseling, and SMI treated with medication and therapy. The full model contradicted the primary hypothesis and two of the four secondary hypotheses, revealing that (1) the medication group reported more assaults than the untreated participants, (2) the untreated group reported fewer assaults than any of the treated groups, and (3) that risk of assault did not significantly differ when compared to medication or combined treatment. Two of the secondary hypotheses were supported in the full model, suggesting that (1) having no indication of SMI protects inmates from assaults in jails, and (2) the combination treatment with medication and therapy among inmates with SMI is a stronger risk factor for assaults than medication alone. However, exploratory analyses indicated that different patterns may emerge when specifically observing assault risk within subgroups by time incarcerated, as well as time incarcerated by race/ethnicity and gender. Based on these results and the limitations of the current study, it is recommended that future research should further investigate assaults by mental health treatment within these subgroups and attempt to establish the temporal ordering of the mental health treatment-assault relationship
Using multiple sensors to approach pavement deterioration through multiple regression analysis and distribution fitting
No full textThe measurement of road roughness is critical to road maintenance. How to adequately determine a threshold value to be used in computing processes in an attempt to determine the levels of pavement conditions has been a challenge. The project presents an approach using regression analysis and probability distribution fitting to analyze patterns and signals collected from a year-long pavement sensing activities on the I-10 corridors in Phoenix, Arizona. A vehicle is equipped with four sensors placed on the top of the control arms of the vehicle and another one is inside of the vehicle to gather the data for analysis. The result of the multiple regression analyses shows that the vibration data from the sensor located inside the vehicle should be analyzed individually and, to avoid statistical invalidity, it should not be included with the other four sensor groups in the analysis for condition assessments. Based on distribution models to fit all vibration data at a specified 99.99th percentile, the threshold values of 1.79 g and 1.28g were determined for use in identifying poor pavement conditions known as significant points in two road sections. Using a single sensor that was placed inside of the vehicle for pavement condition assessment, the threshold of 1.96 was determined through the upper bound of 95% confidence interval in standardization of log magnitudes. All selected significant points visually match with the IRI segments well in GIS software. The ANCOVA results also indicate that the interaction effects of sensor and pavement temperature exist at the significance level of 0.10 in both road sections which describes that the pavement temperature does play an important role in controlling pavement conditions. Based on the Time-Series analysis from the vibrationdata, the pavements are predicted to be deteriorated in two years if the maintenance and rehabilitation will not be scheduled in a timely manner. The paper concludes that using multiple regression analysis and distribution fitting method provides a promoting approach that can be used to help determine the level of different pavement conditions as well as facilitate decision making process for future maintenance
Public archaeology and cultural heritage management in Belize: successes and shortcomings
No full textIn Belize, public archaeology and cultural heritage management are carried out via various community and educational outreach initiatives. Cultural heritage management in Belize falls under the purview of government institutions such as the Institute of Archaeology and the Institute for Social and Cultural Research, both under the National Institute of Culture and History. Archaeological projects in Belize also function as cultural heritage managers. Using both interviews and surveys with various sectors of Belizean society, this thesis presents findings on both the successes and shortcomings of carrying out cultural heritage management in Belize. I also offer, in the discussion, views and recommendations for enhancing such initiatives in Belize