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Examining the Role of Contextual Dynamics in Experimental Approaches to Hominin Behavior
No full textPh.D.Experimental archaeology represents one method used by paleoanthropologists to investigate hominin behavior. Recently, experiments have shifted towards becoming highly controlled and scientific, testing more specific hypotheses about hominin behavior with rigorous and repeatable testing conditions. Accompanying this trend has been a move to utilizing the variation between and within archaeological assemblages as a source for creating research questions, which have created a number of insights into hominin behavior. However, to date, no systematic paleoanthropological study has been completed exploring the value of utilizing the broad behavioral context of artifacts, rather than the lithic artifacts themselves, as a source for research questions and hypotheses. This dissertation tests this approach with five experiments, each testing individual hypotheses about hominin behavior using high levels of experimental control and multiple participants...**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Look at the World with a Vision of Global Governance: Dialogue, Cooperation, and Contemporary Chinese Foreign Policy towards the United States and Africa
No full textPh.D.This dissertation will focus on the development of China’s contemporary foreign policy towards the U.S. and Africa in the context of global governance. Due to China’s history during the first half of the 20th century and the “reform and opening-up” policy, dialogue and cooperation has become the cornerstone of China’s contemporary foreign policy. Dialogue and cooperation in state-to-state relations ensures peaceful approaches to enhance mutual understanding instead of launching military conflicts. Dialogue refers to oral communication between countries, whereas cooperation refers to actions. The reason that the U.S. and Africa have been selected to concentrate on in this dissertation is due to their characteristics. Although the U.S. is the most developed country with the largest economy, while Africa is a region that has the most developing countries and remains the most impoverished continent in the world, China’s contemporary foreign policy towards the U.S. and Africa is similar. Dialogue and cooperation both play a positive role in boosting contemporary China-U.S. relations and China-Africa relations.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Effect of Ultrasound Therapy on Bilateral Masseter Myalgia: Comparison of 1 MHz versus 3 MHz, A Double Blind Randomized Clinical Trial
No full textM.S.Temporomandibular Disorders (TMD) are a group of musculoskeletal and neuromuscular conditions that involve the temporomandibular joints, the masticatory muscles, and all associated tissues. Ultrasound is a common physical therapy modality, however, there is not enough evidence supporting its effectiveness in treating musculoskeletal problems. Specifically, there is a paucity of dose-response data. Aims: The first aim was to compare the effectiveness of 1 MHz versus 3 MHz ultrasound on pain. The second aim was to determine if ultrasound applied to the masseter muscle elicited a segmental effect on the temporalis muscle.Methods. Twenty-four adult females with bilateral myalgia were randomly allocated to either a 1 MHz or 3 MHz treatment group. Average pain level in the last 30 days was taken at the baseline visit and follow-up visit. Therapeutic ultrasound was applied on the masseter for five minutes on each side sequentially at each of four treatment visits. Visual Analog Scale (VAS) for pain and pressure pain threshold (PPT) for the masseter and the temporalis muscles were measured before and immediately after each intervention. Results. No statistically significant difference between mean values of the 1 MHz and 3 MHz groups were found for average pain, VAS for masseter, or PPT for masseter. Also, there were no statistically significant differences between the two groups on the segmental effect measured by VAS and PPT for temporalis. In a secondary analysis with the two groups combined, ultrasound was effective in pain reduction for each of the three measures used and a segmental effect was evoked on the temporalis muscle. Conclusion: There were no statistically significant differences between 1 MHz and 3 MHz ultrasound in pain outcomes or segmental effects. Keywords: Temporomandibular disorders, ultrasound therapy, randomized clinical trial, average facial pain, Visual Analog Scale (VAS), pressure pain threshold (PPT), myalgia,1MHz, 3MHz.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Assessing Disinfection Byproduct Risks for Algal Impacted Surface Waters and Effects of Peracetic Acid Pre-Oxidation
No full textM.S.This study assessed the disinfection byproduct (DBP) risks of algal-impacted surface waters and the effects of peracetic acid (PAA) pre-oxidation on DBP risks. Field samples from three eutrophic lakes were collected over a 13-week period during the algal bloom season. The formation of 11 DBPs (four trihalomethanes, four haloacetonitriles, two haloketones, and trichloronitromethane) in these samples were assessed under uniform formation conditions (UFC) approximating drinking water disinfection. Trihalomethanes formed in the greatest abundance (90–370 µg/L), followed by haloacetonitriles (6.5–87 µg/L), haloketones (0.4–11.4 µg/L), and trichloronitromethane (0.3–9.7 µg/L). Total chlorophyll, a common indicator of algal activity, was not found to correlate with DBP yields. On the other hand, the yields of trichloronitromethane and haloacetonitriles correlated with nitrite/nitrate concentrations and DON concentrations in the samples, respectively. PAA pre-oxidation reduced the formation of trihalomethanes in the subsequent UFC tests in 80% the samples, but promoted the formation of haloacetonitriles and trichloronitromethane in 70% and 50% of the samples, respectively. Analyses of DOC, DON, SUVA, and fluorescence excitation-emission matrices suggest that PAA pre-oxidation can alter the DBP precursors of a sample through the release of high haloacetonitrile/trichloronitromethane-yielding organic matter from algal cells and the oxidative transformation of existing and newly released dissolved organic matter. The results of this study, obtained from surface water samples, suggest that mixed organic matter dynamics is an important consideration for the DBP risks of algal-impacted waters.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
On Routing Unmanned Aerial Vehicles for Surveillance and Reconnaissance Activities
No full textPh.D.As unmanned aerial vehicles (UAVs) have become more prevalent in context of surveillance and reconnaissance, there has been an increasing interest for developing efficient algorithms to optimally route UAVs. However, most common developments on traditional models and algorithms for UAV routing problems are often insufficient to accommodate the needs of UAV routing tasks without introducing fundamental modifications, especially in present moment that new technologies emerge posing new routing challenges. For example, in many pickup and delivery problems, the vehicles often travel in a waypoint-to-waypoint fashion visiting precise locations, which is inadequate for UAV routing because their on-board sensors can collect intelligence data from afar. To better deal with those new routing challenges for UAVs, this dissertation will examine two important UAV routing problems: risk and reward asset routing problem (R\textsuperscript{2}ARP) and close enough traveling salesman problem (CETSP). R\textsuperscript{2}ARP studies how to route a UAV to collect rewards (or information) from a collection of targets by routing within their neighborhoods located in hostile environment. To describe the risk and reward distribution, we consider two general risk-reward frameworks: a continuous model (i.e., functions under some basic assumptions) and a discrete model (i.e., a graph-based model). For the continuous risk-reward model, we consider routing a UAV with two user-defined modes -- linear trajectory and rotatory trajectory -- which accommodate the needs of many real-world applications. To solve the R\textsuperscript{2}ARP, we formulate a mixed-integer programming model based on a discretization scheme. As solving the model directly using current commercial solvers is out of reach for many practical instances, we recast it as a two-stage problem amenable to implement the well-known Benders decomposition method. Various enhancement strategies are provided: fast generation of Benders cuts, strong Benders cuts, a stabilization method and subtour separation procedures. Next, under the framework of the discrete risk-reward model, the trajectory design problem given any entry and exit for a neighborhood is also called reward collection shortest path problem (NP-hard). We propose both an integer programming formulation and an efficient recursive search algorithm, \emph{mPulse} for the problem. To solve large-scale R\textsuperscript{2}ARP instances, we also propose an efficient Lin-Kernighan heuristic with a new definition of flip operation. Compared with lower bound and upper bound we derive, the solutions obtained by this heuristic method is of high-quality and always outperform the classic 2- algorithm on the most tested instances. In addition to our developments for the R\textsuperscript{2}ARP, we also examine the a variation of traveling salesman problem, called CETSP, in which the vehicle must get within a specified neighborhood of each target to visit it. We will study the geometric properties given any compact neighborhoods and propose multiple criteria to characterize the optimal CETSP solutions. We will also propose a tool called projection-closed separators to cut off portions of nonoptimal regions from neighborhoods. From computation perspective, we will propose a mixed-integer nonlinear programming (MINLP) model to formulate the CETSP with trimmed (due to separators) convex neighborhoods. In order to enhance the solvability of MINLP, a generalized Benders decomposition method is applied to solve the MINLP efficiently. Computational results demonstrate the effectiveness of the proposed method.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
The Border and the Market Exploring the Spaces of Exchange and Conflict in the Binational Markets of Ouanaminthe, Haiti and Dajabón, Dominican Republic
No full textM.Arch.Since the 2010 Haiti earthquake, the border between Haiti and the Dominican Republic has emerged as a vital economic engine, where seventy-five percent of the imported food and goods come into the country through fourteen border crossings. The northernmost border crossing between Ouanaminthe in Haiti and Dajabón in the Dominican Republic is the most important and contested of these crossings between the two countries. The livelihood of thousands of Haitians depends on the binational Dajabón market, located on the Dominican side of the Massacre River separating the two cities. Yet, exclusionary regulations, arbitrary enforcement, and racial tensions introduce major precarities in the lives of Ouanaminthe residents. To ease the tensions and provide a more equitable trading arrangement, the European Union funded a new market building on the Haitian side, due for completion in 2020. On its own, the structure is unlikely to address the underlying inequities stemming from the problematic policy arrangements organizing access and trade. Through a series of literature reviews, case studies, and field observations, this thesis examines and situates this contested border setting as a condition of conflict and exchange between the two cities. The thesis also speculates on a new policy framework based on the notion of a new regional agricultural business cluster, and how it can help improve the current border and market conditions.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
STEM Interest Assessment of Adolescents: Construct Validity
No full textPh.D.Recently, the need to increase the pursuit of training in science, technology, engineering, and mathematics (STEM) has been highlighted. To bolster the pursuit of STEM training, researchers have taken a person-environment fit approach that emphasizes enhancing the fit between the characteristics of individuals and the demands of vocational environments. Vocational interests in STEM are a person-level factor shown to play a role in pursuit of STEM careers. STEM interest assessment has been limited by lack of construct validity of single-item measures, structural validity, face validity, content validity, discriminant validity, and convergent validity. Furthermore, despite that decisions about whether to pursue STEM are believed to be made in youth, research about the influence of individual STEM interests on the pursuit of STEM training has tended to study young adults. Therefore, there is a need for a brief, reliable, and valid measure of STEM interests that is at the appropriate reading level for use with younger individuals. The STEM Career Interest Test (SCIT), a brief, multi-item measure of STEM interests, has been shown to have good support for reliability and validity based on the results of factor and correlation analyses with a college sample. The present study examined the reliability and validity of, the SCIT, in samples of eighth (n = 316) and ninth (n = 155) grade students. Good internal consistency was found in both samples, Cronbach’s = .89 and .92. Support was found for the structural validity of the SCIT in both samples. Results of confirmatory factor analysis (CFA) indicate that all indices of fit examined (CFI, RMSEA, SRMR, and Chi-Square) were in the range of acceptable to good fit with a one-factor model of the SCIT after the errors of items 5 and 6 were allowed to correlate. Further, results offer evidence of good external validity in both samples as operationalized as correlations that were generally found to be of the predicted magnitude and in the predicted direction with the six categories of vocational interest domains in Holland’s (1997) theory: realistic, investigative, artistic, social, enterprising, and conventional (RIASEC) as well as with plans to pursue STEM (or not). Specifically, results found support for external validity in large positive associations of the SCIT with investigative and realistic vocational interests (convergent validity), large positive associations of the SCIT with single-item measures of plans to pursue STEM in high school, college, and career (concurrent validity), and small or no association of the SCIT with artistic interest or plans not to pursue STEM (discriminant validity). These results were all directly in line with hypotheses. Mixed support for hypotheses was found in that associations between the SCIT and enterprising and conventional vocational interests tended to be much larger than expected, and the association between SCIT and social interest tended to be somewhat larger than expected. Results of CFA, reliability analyses, and correlation analyses generally provide support for the structural, convergent, discriminant, and concurrent validity of the SCIT in both eighth and ninth grade samples. This study suggests that the SCIT is appropriate for the use with adolescents. Alternative explanations for larger-than-expected associations with enterprising, conventional, and social interests are discussed. In addition, future research should aim to implement multi-item scales to assess external validity, measure test-retest reliability and sensitivity to change, and evaluate validity among individuals who are English language learners (ELL). SCIT appears to be a promising measure for studying educational, research, and counseling interventions designed to foster STEM interest and pursuit.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Interpretative Phenomenological Analysis of Perceived Beneficial Effects and Potential Mechanisms of Action of an Online Randomized Controlled Trial of Mindfulness-Based Stress Reduction for Metastatic Breast Cancer Patients
No full textPh.D.Metastatic cancer patients are living longer lives due to medical and pharmacological advancements. However, cancer still elicits high levels of psychological distress, and most treatment and intervention studies are conducted with individuals with early stages of disease. Patients with metastatic disease constitute an under-researched and underrepresented group and gaps remain in our understanding of effective psychological interventions that will improve the quality of life for these patients. Mindfulness-based interventions have shown promise in reducing psychological distress and improving coping in cancer patients with early stages of disease, and training in mindfulness meditation has been shown to improve coping across a variety of psychological and physical conditions. Additionally, both cancer patients and practitioners have embraced mindfulness as a complementary treatment. However, there is a lack of consensus in the literature about what mechanisms of mindfulness bring about the positive changes associated with mindfulness practice. The goal of this qualitative study was to give voice to the unique lived experiences of women with metastatic breast cancer as they underwent a randomized controlled trial of mindfulness-based intervention at a Comprehensive Cancer Center. Ten women with metastatic breast cancer participated in a semi-structured interview and follow-up. The research questions pertained to exploring the women’s experiences while learning mindfulness, as well as ascertaining what mechanisms of mindfulness were understood by the women in this study to be fundamental components of the practice. Interpretative phenomenological methodology and analysis revealed three overarching themes delineating how mindfulness worked to bring about positive change: (1) Present-Centered Awareness, (2) Acceptance, and (3) Perspective Shifting; with several related subthemes. Beneficial effects of mindfulness that emerged during analysis were: (1) Joy, and (2) Competence; with several related subthemes. Themes from this study were evaluated in light of existing research and theory. These themes highlighted that rather than purely discrete mechanisms, it may be useful to consider the mechanisms of mindfulness as highly interconnected and interrelated concepts that create positive feedback loops that maintain the beneficial effects of the practice. Importantly, the women who participated in this study, despite the adversity they were facing, described utilizing mindfulness as a tool to develop resilience and positive reframing of their cancer into a meaningful experience. Many of them described improved appreciation for life, openness to new possibilities and ways of thinking, development of new strengths and positive coping skills, a sense of personal growth, and examination of their relationships with others from an existential standpoint. The results of this study add to the current paucity of research involving women with metastatic breast cancer. Keywords: Mindfulness, Metastatic Cancer**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Modification of Silica Particles with p-Phenylenediamine by Means of Diazoniuм Chemistry
No full textM.S.With the intent of developing a more hydrolytically stable stationary phases for high performance liquid chromatography (HPLC), a study on the synthesis of a polymeric phenylamine moiety on the surface of superficially porous silica was conducted. Superficially porous silica particles are used as the support material since the use of such particles can produce faster separations with high chromatographic efficiencies. The superficially porous particles were modified by diazotization of p-phenylenediamine. The reaction conditions were adapted to control the number of phenylamine rings on the surface as the thickness of stationary phases directly influences the chromatographic performance. Reaction time, temperature, and molar ratios of the phenylenediamine to surface silanol groups were all investigated as means to control the surface coverage. The modified silica particles were characterized by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and thermogravimetric analysis (TGA). The surface coverage decreased with decreasing temperatures and decreasing reaction times. The conditions tested did not yield a reproducible surface coverage. The surface coverage for samples prepared with longer reaction times (1.5 and 6 hours) at room temperature were significantly too high to be useful for chromatographic purposes. At lower temperatures, the average surface coverage decreased and has potential for further investigation of reproducibility.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*
Electrochemical Methods for Biofilm Detection and Characterization of Electrically Stimulated Orthopedic Biomaterials
No full textPh.D.Peri-prosthetic joint infection (PJI) continues to be a significant complication associated with joint arthroplasty. Due to the formation of biofilms on the implanted device, PJI can be difficult to both detect and to treat. Recently, the use of electrical stimulation has been developed as a method for the treatment of PJI. The work presented in this dissertation sought to develop electrochemical methods for both the detection of orthopedic implant associated infection, and for the characterization of the cathodically stimulated metallic biomaterial interface, to better understand the associated antimicrobial mechanisms...Overall, this work lays the groundwork for further development of electrochemical methods for the treatment and detection of PJI. The methods developed herein can be used to establish a method for the electrochemical evaluation of implanted metallic devices, and to continue to refine the understanding for faradaic antimicrobial mechanisms.**To request an accessible version of the file(s) associated with this item, contact [email protected]. Please include the item's persistent URL [http://hdl.handle.net/. . .] in your request.*