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Examining Effects of a Cultural and Family Resilience Program on Improving Physical Activity and Eating Behaviors Among Overweight Black Adolescents
No full textBlack adolescents have higher rates of physical inactivity, lower quality dietary intake, and fewer family meals compared to their White peers. These health inequities place Black adolescents at greater risk for overweight and obesity, as well as long-term health consequences, including chronic disease and early mortality. However, few health promotion programs have been successful in improving health behaviors among Black adolescents and families. Elevated rates of chronic stress, namely racial stress, among Black families may be a prominent obstacle for engagement in and effectiveness of health promotion initiatives. Limited family-based health promotion programs with Black families have incorporated cultural and family resilience frameworks to address stress, namely racial stressors. Of the limited existing resilience trials, prior trials have only included a limited set of core resilience resources, often overlooking racial identity and cultural assets, and have been limited in methodological rigor. Moreover, to the best of our knowledge, none have targeted health promotion behaviors as outcomes except for our research team’s recent LEADS feasibility trial. Preliminary work from the LEADS feasibility trial shows initial feasibility and acceptability of cultural and family resilience curriculum with overweight/obese Black adolescents and families; however, feedback from LEADS families on cultural curriculum was limited to a small sample size of 10 dyads and only targeted physical activity outcomes. Thus, the current study included the integration and evaluation of novel cultural and family resilience intervention curriculum with all core resilience resources, gathered real-time feedback from a larger sample of dyads, and examined health behavior changes from a wider range of outcomes (physical activity, dietary intake, family meals). The proposed study aimed to fill the gaps in prior research and expand on the LEADS feasibility trial with the following aims to 1) assess parent and adolescent feasibility and acceptability of intervention curriculum, family curriculum engagement, and family interactions, and to 2) assess changes in adolescent physical activity, dietary intake, and family mealtime from Timepoint 1 to Timepoint 2. Data were collected from Black adolescents and their parent/caregiver (n = 31 dyads; Madolescent age = 13.4 years; 58.1% female; MBMI% = 96.3%). Process evaluation findings demonstrated high feasibility and acceptability of resilience intervention curriculum, moderate family engagement with curriculum, and strong parental support and positive family interactions and communication. In line with hypotheses, findings also demonstrated trending improvements in adolescent-reported family mealtime frequency and fruit and vegetable intake and trending reductions in snack intake and sweetened beverage intake among the intervention group from Timepoint 1 to Timepoint 2. Contrary to hypotheses, adolescent-reported family mealtime quality showed slight trending declines among both the intervention and control group. Follow-up qualitative feedback highlighted strengths of the program (e.g., approached challenging conversations about race, increased family bonding, increased stress coping tools) and recommendations for improvement for future resilience trials (e.g., culturally salient coping, discuss more health inequities, integrate financial literacy). These findings provided notable insights that informed the LEADS R01 trial and provide preliminary support for future family-based resilience health promotion programs conducted with Black families
Purification of Uranium Tetrafluoride Using Ammonium Bifluoride
No full textA method of purification for UF4 utilizing NH4HF2 was investigated to remove oxygen and hydrate impurities from the salt. The original salt exhibited a melting point at 915–920 °C, which corresponds to the eutectic temperature of the UF4-UO2 system, showing clear signs of oxygen contamination. To purify the salt, an air-tight reaction vessel inside an argon glovebox was used to react UF4/NH4HF2 mixtures at elevated temperatures under a continuous flow of inert gas. The process yielded a significantly purer UF4 salt as confirmed via inert gas fusion, X-ray diffraction, differential scanning calorimetry and inductively coupled plasma-optical emission spectrometry
Investigation of Americium-Containing Phosphates, Silicates, Borates, Molybdates, and Fluorides Synthesized via High-Temperature Flux Crystal Growth
No full textThe crystal chemistry of americium-containing extended structures was investigated, and several classes of americium-containing solid-state oxide materials were obtained in single-crystal form via high-temperature flux crystal growth. This enabled the structural characterization of rare examples of ternary, quaternary, and penternary americium-containing silicates K3Am (Si2O7) and Cs6Am2Si21O48, phosphates Na3Am (PO4)2 and K3Am (PO4)2, borates Ba3Am2(BO3)4 and AmBO3, borate halides Ca5Am(BO3)4Cl, molybdates Li0.5Am0.5MoO4, and fluorides CsAm2F7. Using these crystallographic data, the ionic radii of Am3+ with coordination numbers of six (0.975 Å), seven (1.052 Å), and nine (1.162 Å) were established. A maximum entropy method (MEM) analysis was performed on the single-crystal X-ray diffraction data that were collected for K3Nd(PO4)2/K3Am(PO4)2, K3NdSi2O7/K3AmSi2O7, and NdBO3/AmBO3, to qualitatively compare the ionicities of the Nd-O and Am-O bonds. Raman spectroscopy data were collected on single crystals of K3Am(PO4)2 and compared to the calculated Raman spectrum of K3Am(PO4)2 obtained from DFT calculations
Modification of Nanoparticles for Designed Interfaces
Get PDFThe work contained herein, is focused on the design, synthesis, and characterization of polymer nanocomposite interfaces and the property enhancement afforded from said interface design. Through the use of reversible addition fragmentation chain transfer (RAFT) polymerization for the grafting of polymer chains to silica nanoparticles, the surface of silica nanoparticles can be manipulated to tune the properties of the nanocomposite as a whole.
In the first part of this work, heterogeneity is introduced onto the surface of silica nanoparticles via a sequential RAFT polymerization to afford a bimodal brush system. A densely grafted, short brush population is polymerized from the surface in order to provide screening for the enthalpic core-core attraction of the nanoparticles that can lead to agglomeration. Afterwards a second sparsely grafted, long brush population is polymerized to enable the nanoparticle to entangle with the polymer matrix overcoming the entropic preference of the grafted chains dewetting from the matrix chains. These two populations and all their respective molecular variables (graft density, chemistry, end-group chemistry, polydispersity, etc) can be controlled with this approach. With this control in place, the molecular variables were used to produce both bimodal and monomodal samples for comparison of their resulting properties when dispersed in a polymer matrix. It was found that not only do the bimodal samples improve dispersion when compared to monomodal brushes, but that the thermomechanical properties are enhanced as well. Tuning of the long chain graft density determined that very low graft densities were better for improving entanglement. The first bimodal kinetic study was performed to prove that control over the polymerization can still be obtained using RAFT even when a dense brush is already in place.
Secondly, following the information gained from our first bimodal samples, it was ascertained that with our bimodal system the enthalpic attraction of the particles and the entropic dewetting of the grafted chains were decoupled. This allowed us to pursue the synthesis of mixed bimodal samples. In a mixed bimodal sample the chemistries of the brush populations are distinct. If the long chains are the only population entangling with the matrix, then it can remain matrix compatible while the short brush can be varied to improve other desired properties of the nanocomposite. In order to test whether monomer/polymer incompatibility would allow for the diffusion of a monomer past a short but dense brush of polymer it phase separates with to the surface, a simple poly(methyl)methacrylate/polystyrene mixed bimodal brush was made. With both variations of either chemistries short or long, bimodal samples were possible with control of all previously mentioned molecular variables. In order to push that testing further, bimodal samples of poly(1H,1H-heptafluorobutyl methacrylate) short brushes and polystyrene long brushes were made. A film of these nanoparticles were drop cast onto various substrates showing increased water contact angle measurements when compared with untreated samples. The drop casting of this film onto a sheet of polystyrene followed by annealing shows that the long polystyrene chains of the mixed bimodal brush can still entangle with the polystyrene of the substrate.
For the third section, further work was performed to develop new approaches to the synthesis of bimodal brushes. Taking cues from our testing that showed lower graft densities improved entanglement, it was decided to pursue a one-pot bimodal brush synthesis using a grafting-to approach. While grafting-to is incapable of producing high graft density brushes, this was not needed for our improvement in dispersion and entanglement. Since RAFT polymerization allows for control of the polymer chain end chemistry, the efficiency of post-polymerization modification was compared to using a modified/activated RAFT agent. The activated RAFT agent showed higher graft densities while still allowing the use of a thermally initiated, bulk polymerization without decomposing at the higher temperatures required for it. This allows for decreased solvent use and therefore easier scale-up. Both long and short chains were attached in a one-pot approach. While not having the control of the sequential RAFT polymerization process, it is much simpler, more efficient, and more modular than the multi-stepped procedure. In addition to overcome issues with characterization of bimodal brushes produced via a one-pot procedure, a new anthracene-containing initiator was created and used to end-label one population of chains via a radical cross coupling mechanism. This allows for characterization of each chain population independently using a combination of UV-Vis and TGA.
Finally, new synthetic strategies towards the modification of the silica nanoparticle surface via different ligands while also focusing on improving efficiency. Previous approaches used a linear aminosilane for the coupling of the RAFT agent to the surface. While successful, the reactions take hours to complete. In a new approach, an amine-containing cyclic azosilane was used for the modification of the silica surface in under five minutes. This new ligand has the same ability as our previous method to be varied in loading in order to vary the graft density. RAFT polymerizations of poly(methyl)methacrylate and polystyrene were performed at various graft densities to show that the attached RAFT agent retained its viability after attachment
Vital Language Practices and Attitudes Among the Lumbee
No full textThe longstanding interest among linguists and linguistic anthropologists in Indigenous languages has increasingly adopted a Critical Indigenous framework, which has been promoted by Indigenous scholars and community leaders as a means of decolonizing “salvage” collection of Indigenous language materials. An important aspect of Critical Indigenous theory is the framework of vitality—that is, an emphasis in literature and community practice on the everyday living and lived elements of culture. One means of promoting Indigenous language within this Critical framework of vitality that is community-centered is centering vital language practices in community-based archives, which seek not to document the language as it is spoken by some subset of the population but to create resources for people to access the stories, family histories, and practices of their communities, in the voices of community members. This thesis is based on interviews and literature on the Lumbee, an Indigenous group in North Carolina, and seeks to use the existing and prospective future practices of the Lumbee to understand the broader process of community archiving based on vital practices. Certain vital practices, such as pageants and co-narration of family- and community-based stories, are an important part of how Lumbee use language. Archiving is another major concern for many members of the community. This thesis explores historical precursors of vital language practices practiced in Lumbee families and communities and their relationship with often inaccessible means of archiving, and provides a critical analysis of what is available, to whom it is available, and how it is accessed
The USC Sports Sorority: A Podcast Highlighting the Experiences of SJMC Alumnae Working in Sports Media
No full textWomen’s sports are on the rise, as indicated by increased media interest and television viewership records across the professional and collegiate ranks. This trend coincides with one specific to the sports media industry, where more women are pursuing careers in that space – and being recognized for their contributions in ways they have not in previous decades.
My project examines both trends in the form of a podcast, featuring interviews with eight alumni and two current students who have sports media experience and ties to the University of South Carolina’s School of Journalism and Mass Communications. The podcast consists of four episodes – one serving as introduction, two that focus on journalism and social media, and another that contains interviews with students and pieces of advice for listeners. Each of these episodes also includes testimonials from industry professionals about experiences that helped them discover their passion for sports media, reinforce the importance of women’s sports, and form strong bonds with female peers and mentors.
This podcast engages in important dialogues surrounding gender diversity and representation in the sports media industry and aims to be a source of inspiration for women aspiring to pursue careers in that field
