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Shame as an Affective Component of Pain Experiences
No full textThe experience of pain is a warning that potential harm has come to the body. Furthermore, pain is recognized as a biopsychosocial phenomenon, with a person���s traits, emotions, social interactions, and environments all encompassing pain outcomes. As such, identifying specific psychological components of the experience of pain may help further guide our understanding of the manifestation and persistence of pain. One potential aspect of pain may be the self-conscious emotion of shame, a feeling arising from the judgment of others acting as a warning that something about one���s self is socially unacceptable. Indeed, people living with chronic pain frequently express feeling shame because of how pain impacts their lives; however it has not been assessed in relation to the exacerbation of pain itself. Therefore, this dissertation employed four studies examining the relationship between shame and pain, specifically hypothesizing that greater feelings of shame would be associated with greater pain experiences. Studies 1a and 1b were correlational online studies, finding that shame was positively associated with clinically relevant self-report of pain. Study 2 found a similar relationship with self-reported measures of central sensitization, but not laboratory-based sensory measures central sensitization as assessed by mechanical temporal summation. Study 3 explored the relationship between shame and endogenous opioid response measured using conditioned pain modulation, and also did not find support for the overarching hypothesis. Study 4 utilized a daily diary design to observe actual lived experiences of shame and pain, and found that people experienced greater pain severity and interference on days they felt more shame. Although results were mixed across studies they provide a foundation for future understanding of the relationship between shame and pain outcomes with implications for clinical treatment and care
Characterization of a Hypersonic Turbulent Boundary Layer Using the VENOM Technique
No full textModeling fluctuating flow parameters of high speed laminar and turbulent boundary layers is essential for understanding the thermal loading experienced by vehicles re-entering the atmosphere. Hypersonic turbulent flows in particular are challenging to model due to the strong coupling of velocity and energy which drive heat flux. Experimental data of the relationship between these fluctuating quantities are limited due to the required simultaneous measurements of velocity, temperature, and density. Laser diagnostics have become key to measuring these fundamental parameters in unsteady hypersonic flows due to their non-intrusive nature and ability to provide fluctuating measurements, which can be used to assess current predictive turbulence models.
Mean and instantaneous velocity and temperature measurements using the ���Invisible Ink��� Vibrationally Excited Nitric Oxide Monitoring (VENOM) laser diagnostic are presented to characterize the hypersonic boundary layer above a 2.75 degree half-angle wedge test article. The measurements were performed in the Actively Controlled Expansion (ACE) blow-down wind tunnel under both laminar and turbulent conditions. A double dependent Gaussian fitting velocimetry algorithm was developed to account for laser reflections at the wall, and intensity fluctuations due to turbulent motion. Additionally, rotational temperature profiles were using a thermometry algorithm in conjunction with velocity information extracted from each image. The results demonstrated a uniform laminar flow across the flat plate which broke down to turbulence in response to inserted mechanical trips. Freestream fluctuations compare favorably to previous measurements. The laminar boundary layer fluctuations peak around 12% for the velocimetry results and 20% for the thermometry results. The turbulence fluctuations peaked around 18% and 24% for the velocimetry and thermometry results respectively. Using the laminar results as a baseline for the technique uncertainty, it is estimated the true turbulence fluctuations are on the order of 10���15%. The mean and instantaneous measurements qualitatively agree with previous separate velocity and temperature measurements and simulations. The generated database of instantaneous parameters can be used to directly determine the variable heat flux of the flow over the wedge surface using a constant specific heat model to assess current predictive turbulence models. The current measurements are analysis can also serve as a basis for future multi-component velocity and temperature boundary layer measurements, contributing to a comprehensive understanding of turbulence, a complex 3D phenomenon
Triple-Tuned Radiofrequency Coil Designs for Magnetic Resonance Imaging and Spectroscopy
No full textMulti-nuclear MRI/S has been shown to be a powerful tool for both diagnostics and the study of disease. While the potential of this technology has been recognized for decades, widespread clinical adoption of these techniques has been limited in large part due to the continued inaccessibility of multi-nuclear hardware. The work presented here aims to address the many design considerations of multi-nuclear RF coil designs, which are necessary to support biomarker development for Duchenne muscular dystrophy (DMD).
This work specifically details the design, construction, and characterization of several triple-tuned coil designs. First, a triple-tuned nested volume coil design composed of a pair of nine-leg birdcages designed to create parallel fields and an orthogonal saddle coil insert at 4.7T. The nine-leg birdcage pair was designed such that it could geometrically decouple from any orthogonal insert coil, either a dedicated planar receive coil or an orthogonal volume coil to operate in either the double- or triple-tuned configurations. SNR comparisons were specifically drawn between geometric decoupling design and active detuning.
Next, a truly simultaneous triple-tuned trap design was investigated for the use in scalable receiver arrays. This design proposes a parallel trap network in place of a more conventional series design to theoretically decrease the equivalent series resistance of the resultant trap network. A roughly 20% improvement in SNR was seen for 1H, but the theoretical sensitivity gains for the X-nuclei frequencies could not be fully resolved. The parallel trap network was compared to both a double- and triple-tuned series trap designs. X-nuclei sensitivities were close in both the double- and triple-tuned reference coils, indicating the additional losses from triple-tuning are minimal in comparison.
Finally, a modular multi-nuclear array was designed and characterized to enable a biomarker study on canine models of DMD. This design used a series PIN diode as a broadband active detuning network to enable decoupling independent of both position and frequency for stacked receive coils. Comparisons were specifically made between this broadband network and a conventional narrow band trap detuning mechanism. Comparisons were also made between a single larger loop and an inscribed array for 1H, 31P, and 23Na
D-modules and the Cauchy-Kovlevskaya Theorem
No full textThis is an expository article served as an elementary introduction to the theory of algebraic D-modules. For the first part, we give the definition and basic properties of D-modules. We take advantage of the sheaf theory and compare the results of complex manifolds with those on affine spaces. We particularly focus on introducing the characteristic varieties of D-modules. For the second part, we introduce the classical Cauchy-Kovalevskaya theorem. Using the languages of category theory and homological algebra, we give a generalized version on affine spaces, which is a simplified version of the Cauchy-Kovalevskaya-Kashiwara theorem
Direct Synthesis of Dimethyl Carbonate from Carbon Dioxide and Methanol, Investigating the Effect of Reaction Conditions and Dehydrating Agents
No full textDimethyl carbonate (DMC) is attracting attention lately because of its environmentally friendly characteristics as it is known to be a non-toxic, non-corrosive, and biodegradable material. DMC direct synthesis presents an environmentally friendly approach as it utilizes carbon dioxide (CO2) and does not use hazardous materials as in other processes. Despite its potential for CO2 fixation, several challenges restrict methanol conversion to DMC to around 1%, primarily due to water formation favoring DMC hydrolysis. Therefore, solution such as the use of dehydrating agents and a reactive distillation have been proposed. Different dehydrating agents have been experimentally studied such as zeolite 3A, zeolite 4A, and ZSM-5. Before assessing dehydrating agents, various experiments were conducted to optimize reaction conditions, revealing that the highest DMC yield occurs at 110��C, 30 bar pressure, 200 mg catalyst dosage, and a 2-hour run duration. Tested dehydrating agents slightly increased DMC % yield; however, they failed to shift the equilibrium adequately. Consequently, reactive distillation is seen as a promising alternative, necessitating a kinetic model for accurate prediction. A low-pressure kinetic model was developed within this work, showing good agreement with experimental data (MAPE: 17%). After that, a CO2Fix metric was used to study the potential of the direct synthesis method for CO2 fixation. Based on the model, it was concluded that 2-CP exhibits the highest CO2Fix potential with a 3.68 CO2Fix. Moreover, it was determined that compounds with 6-membered nitrogen heteroaromatic ring such as benzonitrile, acetonitrile, and shows higher CO2Fix potential compared to other dehydrating agents
A Tide That Raises All the Boats: The Soviet Threat, NATO, and Marine Corps Innovation, 1969-1991
No full textAfter suffering the bitter defeat of the Vietnam War, the United States Marine Corps entered a nearly two-decade long period of reform and modernization. By the end of the Cold War in 1991, the service had markedly improved its training, equipment, doctrine, and proficiency for mid- and high-intensity conventional conflicts. Notably, the capabilities gained during the 1970s and 1980s remained in place well into the twenty-first century, marking this era as one comparable to the service���s most storied periods of innovation. The existing historical literature of the late-Cold War Marine Corps ascribed the service���s rise either to its military culture or crises in Southwest Asia. Such interpretations, however, overlook the impetus provided by the Soviet military threat and North Atlantic Treaty Organization (NATO) missions. An analysis of multi-archival and multi-service sources ��� including declassified war plans and studies, strategies and concepts, congressional testimony, exercise reports, student papers, journal articles, memoirs, oral histories, interviews with participants, commentary from NATO allies, and related secondary histories ��� demonstrates that the Soviet threat and NATO missions were salient driving influences on Marine Corps innovation during this period. This impetus, ever present, often unacknowledged, and occasionally even strenuously denied, provided the service with a unique azimuth of innovation, one qualitatively different from the id��e fixes of other militaries. The resulting service strategy served as a ���tide that raises all the boats,��� a focus on the severest test ��� a Soviet anti-amphibious defense in Europe ��� that simultaneously rehabilitated the Corps��� political relevance, modernized readiness, and inspired future concepts, all while still preserving flexibility for global employment across the spectrum of conflict. Accordingly, at Cold War���s end, observers praised the Corps as the ���most general-purpose force of the general-purpose forces,��� a service particularly well-suited for the uncertain new security environment. This dissertation advances historical interpretations of the Marine Corps and military innovation in the late-Cold War and demonstrates the effectiveness of threat-based strategies of innovation, providing a case study of value both to scholars of military innovation studies and strategic practitioners
Nitrogen-Containing Organic Bases for Molecular Electronic and Biological Investigations
No full textThis dissertation shows the efforts towards tailor-made nitrogen-containing organic base molecules for modular electronic studies as well as biological investigations. The first part features the development of two different kinds of aniline-derived conjugated molecules and their applications as molecular models for single-molecule junction studies. The second part of this dissertation describes the development of a series of polyamine-based detergents and their applications in native mass spectrometry studies of membrane proteins.
First, a general introduction of nitrogen-containing organic bases is presented in Chapter I. Example molecules and their applications including pharmaceuticals, metalorganic frameworks (MOFs) and conducting polymers, specifically polyaniline (PANI), are discussed.
In Chapter II, the design and synthesis of a ladder-type polyaniline-inspired single-molecule switch are presented. With exceptional electrochemical stability rendered by the ladder-type constitution, the molecule can be converted between three distinct molecular states characterized by varying levels of protonation and oxidation. In collaboration with the Schroeder Group at UIUC, we demonstrate its superior conductance and multi-state switching capabilities through electrochemical scanning tunneling microscope break-junction (STM-BJ) experiments. Our results suggest that ladder-type molecules are promising candidates for advanced single-molecule electronics. This work also sheds light on the mechanism of electronic conductivity of redox-active conductive polymers.
Chapter III describes the motivations of a model study involving oligo(para-phenylene)s within a graphene single-molecule junction for mechanistic studies of RCM in the synthesis of ladder polymers or oligomers. The design and synthetic efforts towards the target molecules are the main foci of this chapter.
Next, in Chapter IV, synthesis and purification towards spermine-derived detergents are described. These detergents are employed as additives/co-detergents in native mass spectrometry (MS) studies of various membrane proteins. Their effectiveness in achieving reduced average protein charge states and preserving membrane proteins in more intact states has been demonstrated. Our research in this area laid the groundwork for the molecular design principles of charge-reducing detergents with enhanced protein solubility and improved compatibility with commercial detergents. These principles are crucial for conducting native mass spectrometry studies of membrane protein complexes.
Lastly, Chapter V concludes the entire dissertation by providing an overview of the findings presented in the preceding chapters. Additionally, future research perspectives that promise to shed further light on both fields are discussed
SMC-M1 Connectivity and Motor Sequence Learning: A TMS Study
No full textWe experience various types of motor learning throughout our lives. As children, we learned to walk unconsciously. As we grow older, we continue to learn skills like sports or musical instruments. In this study, the primary motor cortex (M1) and the supplementary motor complex (SMC), which are brain regions involved in motor sequence learning but where many aspects still remain unclear, were mainly investigated, and the connectivity of these two regions was measured using the paired-pulse transcranial magnetic stimulation (ppTMS) technique. In Experiment I, sixty-three right-handed undergraduate students participated. Conditioning stimulus (CS) was administered at SMC (i.e., 4 cm anterior to Cz), and test stimulus (TS) was applied at M1. As a result, consistent with the previous ppTMS studies, a facilitatory influence was observed between SMC and M1. In Experiment II, fifty-one right-handed undergraduate students participated. After measuring baseline SMC-M1 connectivity in the same way as in Experiment I, individuals practiced one of three motor sequential tasks (i.e., implicit, explicit, or random sequence task). After practice, ppTMS as post-training stimulation was administered in the same way as the baseline stimulation to investigate the changes in the connectivity between SMC and M1. As a result, it was found that the facilitatory influence decreased after the explicit sequence task that involved motor chunking. This may be because SMC plays a role in motor chunking. In Experiment III, instead of a motor task, intermittent theta-burst stimulation (iTBS) was administered at SMC between two ppTMS sessions, and the connectivity changes were investigated. Similar to the influence of the explicit sequence task in Experiment II, the facilitatory influence decreased in the iTBS group. Although the mechanisms are different from each other, iTBS appears to induce post-synaptic plasticity in the cortico-basal ganglia-thalamic network. After post-stimulation of ppTMS, participants performed the explicit sequence task used in Experiment II twice (i.e., practice and retention test) to reveal the effect of iTBS on motor sequence learning. In the iTBS group, the offline improvement was disturbed at concatenation points compared to the Rest group. In the future, follow-up research that dissociates motor chunking conditions using neuroimaging techniques seems necessary
Theory and Applications of Mixed-Integer Fractional Programming
No full textThis dissertation is focusing on developing theoretical and practical results for a class of mixed-integer problems with fractional objectives. We introduce the generalized clique relaxation models with fractional objectives, namely the maximum ratio s-plex problem and the maximum ratio s-defective clique problem. We establish complexity results, describe solution methods, as well as introduce valid inequalities that are shown to substantially improve the performance of the proposed formulations. Then we we discuss the application of Bron-Kerbosh algorithm for solving fractional clique relaxation problems. We develop a new efficient combinatorial approach best suitable for sparse graphs. Finally, propose an extension of knapsack problems with fractional objectives arising from applications in service systems design and facility location problems with congestion
Views of Rural Community Members on Building or Rebuilding Public Trust in Healthcare
No full textHow, why, and what determines public trust in health entities is a critical element that is yet to be well documented particularly among rural residents. Identifying the perceptions of rural community members on trust in health entities is considered a fundamental strategy for improving health outcomes. To investigate the views of rural community members on trust in health entities, the purpose of this study was to assess and conceptualize a framework of building and rebuilding public trust in health entities among rural communities in the U.S.
Two different research strategies were utilized to complete this dissertation. First, a mixed-methods approach including a review process with systematic elements was performed to locate and evaluate the literature followed by a narrative approach to complete a scoping review. Second, a qualitative research study was used to explore the views of rural community members on trust in health entities using three different interview formats (intercept, dyadic, and focus groups).
Three major themes emerged based on both the scoping review and the qualitative research study. The themes included sources of information, trust barriers, and rebuilding trust which further resulted in other subthemes within each of them. The most common sources of information identified by both studies were medical professionals. Trust barriers according to the scoping review were specific to the health outcome and therefore the response identified varied from what was recorded in the qualitative studies. The qualitative study identified low expectations as the most dominant barrier of all others listed. Likewise, strategies identified for rebuilding trust included the inclusion of leadership engagement strategies, increasing awareness through information, and availability of services as the most presented.
In conclusion, the findings of the dissertation noted that strategic and multidimensional measures are required that are sustainable and long-term in order to increase public trust in health entities among rural communities in the U.S