Master of Science (M.S.), University of Dayton, 2016, Electrical Engineering

This study suggests improvements and an extension for the No-Reference Image Enhancement Quality Metric And Fusion (NRIE-QMF) Technique, that measures a perceptual quality score. To mesure the quality score, the NRIE-QMF metric uses the image statistics based on brightness, contrast, and noise content. The NRIE-QMF uses several image inputs from various image enhancement methods (GHE, CLAHE, and LTSN) and calculates a score value for each pixels based on the local neighborhood statistics. Then respective pixel scores of each enhanced image are weighted and fused into one to create a combined image. The NRIE-QMF metric is analyzed for execution time using the MATLAB profiler. Few modification and optimization steps are carried out to increase the execution speed while maintaining a good output. Secondly, enhanced images are scored using the proposed metric and the score matrices are thresholded compared to the original image's score matrix to avoid over-amplification caused by some enhancement methods. Finally, it is shown that the proposed metric achieves a 85.8% speed increase compared to the NRIE-QMF method and generates a combined output image with a superior visual quality. Also, quality score of the new combined image results higher than those of the enhanced images used for fusion, demonstrating the superiority of the proposed method's fusion technique.

Master of Arts (M.A.), University of Dayton, 2018, Psychology, General

The primary aim of this study was to determine if there is a causal association between self-enhancement and spending behavior. A secondary aim was to further examine the causal association between self-enhancement and well-being and whether it relates to spending behavior. A 3(self-enhancement, positive affect, control) between-subjects design was employed with spending and well-being as the dependent variables. Mechanical Turk Participants (N=156) completed pre-manipulation measures of self-esteem and affect followed by the experimental manipulation. Participants were randomly assigned to either self-enhance by writing about their most important characteristic in comparison to other college students, increase positive affect by writing about a positive memory, or to move directly on to the rest of the study as a control. Participants then completed post-manipulation measures of self-esteem and affect to determine if self-enhancing affected self-esteem and affect differently compared to the positive affect condition and the control. Participants then completed a measure of their shopping motivation, a hypothetical shopping task which was used to measure spending, and several well-being measures used to form a composite measure of well-being. The results were computed using separate one-way analyses of variance for both spending during the shopping task and the well-being composite. The results failed to support the primary hypotheses that a negative causal association between self-enhancement and spending compared to the positive affect and control conditions and a positive causal association between self-enhancement and well-being compared to the control condition would be found.

Master of Science (M.S.), University of Dayton, 2016, Electrical Engineering

This thesis presents a color image enhancement method that uses an existing method (developed for grayscale images) to adjust the luminance component of a color image towards intensifying details without debasing the images' perceptual quality. For color modifications, the proposed method uses Adaptive and Integrated Neighborhood-Dependent Approach for Nonlinear Enhancement (AINDANE), a superior method originally defined for improving color images captured under low-light. Furthermore, utilization of an appropriate white balancing technique gives rise to a color temperature controlled final image. It is shown that a no-reference quality metric scores higher for final enhanced images of selected diverse images and a comparison with AINDANE shows the competitiveness of the proposed method. Finally, a statistical factor based graphical representation displays a convergence towards the visually optimal range.

Master of Science, The Ohio State University, 2016, Electrical and Computer Engineering

The objective of this work is to develop a new technique of digitally controlled, second order linearization of an active mixer, along with incorporation of other standard linearization techniques. The performance of various techniques was studied and the one suitable for this design was chosen. The digital control stems from the fact that the second order non linearity is a result of the mismatch introduced in the switching pair. The system level design tool CppSim was also explored to conclude the ability to transfer the cadence design points to CppSim. Various simulations were done to check the performance of the mixer. The choice of bias points for optimal gain and linearity were explored

Master of Science (M.S.), University of Dayton, 2015, Electrical Engineering

Image quality has always been an important aspect of the image processing field. Subjective quality is useful since images are a visual medium, but objective quality measures are needed because they are unbiased and can be used as parts of larger processing systems. Many image quality metrics exist that attempt to give an objective score to an image based on its likeness to a reference. These metrics work well if the reference is known and the test image is assumed to be a distorted version of the reference. However, in areas such as image enhancement, the reference image is generally worse than the test image and measuring likeness between the two is not a good indication of visual quality. A no-reference image enhancement quality metric is proposed in this paper that uses three factors to score images: lightness, contrast, and noise. It has been shown in literature that certain ideal ranges for lightness and contrast exist, and image enhancement techniques tend to push an image towards these. The metric gives each pixel in an image a score based on its neighborhood statistics. An image fusion technique is also proposed that fuses multiple enhanced images into one based on the local scores obtained from the no-reference metric. It is shown that this fused image scores higher using the no-reference metric and also has superior visual quality.

Master of Science (M.S.), University of Dayton, 2024, Electrical Engineering

RGB imagery provides detail which is usually sufficient to perform computer vision tasks. However, images taken in low-light appear vastly different from well-lit imagery due to the diversity in light intensity. Polarimetric data provides additional detail which focuses on the orientation of the light rather than intensity. Scaling our classic RGB images using polarimetric data can maintain the RGB image type, while also enhancing image contrast. This allows transfer learning using pre-trained RGB models to appear more feasible. Our work focuses on developing a large dataset of paired polarimetric RGB images in a highly controlled laboratory environment. Then, we perform transfer learning on a pre-trained image segmentation model with each of our image product types. Finally, we compare these results in both well-lit and low-light scenarios to see how our polarimetrically enhanced RGB images stack up against regular RGB images.

Master of Science in Engineering, Youngstown State University, 2024, Department of Mechanical, Industrial and Manufacturing Engineering

With the constant innovation of technology and the need for more power generation, the need for improved methods of heat transfer are also needed. These innovations have always driven the research into new and improved methods of heat transfer. The topics covered in this research mainly being porous media, submerged two-phase jet impingement and boiling have all been seen to create improvements in cooling but have not been used in conjunction with each other. Using this combination to find the possible heat transfer improvement is the goal of this research. Experiments are done in both a non-boiling and boiling scenario. This allowed for verification that the two-phase flow had an effect on the surface before performing a boiling experiment. Two surfaces were tested, these were a plain surface and a columnar post-wick porous structure. For both sets of experiments, water flow rates were chosen from Reynolds numbers of 729 and 2929. The air flow rates were calculated using values of the volumetric quality (𝛽) that ranged from 0 ≤ 𝛽 ≤ 0.9 and the previously mentioned water flow rates. The results of this experiment were quantified by looking at the heat transfer coefficient (HTC) compared to the change in volumetric quality for both experiments. The non-boiling experiment showed that the added two-phase impinging jet created improvements in the HTC of porous media. An improvement of 81.94% over a single-phase jet was observed at a volumetric quality of 𝛽 = 0.9. The boiling experiment showed that the added two-phase impinging jet made minimal improvements on each surface. The plain surface saw an improvement of 9.50% over a single-phase jet at a volumetric quality of 𝛽 = 0.9. The post-wick surface saw a maximum improvement of only 2.94% at a volumetric quality of 𝛽 =

Master of Arts, The Ohio State University, 2024, Bioethics

As technologies are developed and implemented at increasingly faster rates, an ethical assessment of human enhancement theory is warranted for the creation and efficacy of public health policy and medical practices. I will begin this assessment with a critique of one popular approach to ethical enhancement through the work of Allen Buchanan, who advocates for an ethics of development based on distributive justice, then I offer an ecofeminist ethics of care as an alternative way forward for the field of healthcare. At the root of an ethics of care is the concept of the human as a socially and ecologically embedded being, with shared dependencies and vulnerabilities. I will explore the implications of such a framing of humanity for the enhancement debate through the works of Chris J. Cuomo and Val Plumwood, then examine in vitro fertilization as a case study for the applicability of ecofeminist theory. In the end, I argue for a collaborative pursuit, despite the differences between these ethical methods, and call for further research in applying an ethics of care in the clinical enhancement setting.

Doctor of Philosophy, Case Western Reserve University, 2024, Chemistry

Human immunodeficiency virus (HIV) and other RNA viruses pose a major threat to human health. Current therapeutic options are limited due to the multifaceted protein-RNA interactions that drive the lifecycle of HIV. The human heterogeneous nuclear ribonucleoprotein (hnRNP) H is a dynamic RNA-binding protein (RBP) that participates in many stages of RNA metabolism in humans and viruses alike, including in HIV type 1 (HIV-1). G-tracts—stretches of RNA consisting of three or more consecutive guanines—are the binding partners of hnRNP H. G-tracts are important splicing elements, and, due to their abundance, HIV-1 can recruit hnRNP H to bind to viral G-tracts within its genome. The interactions between hnRNP H and G-tracts can be studied using common 2D NMR techniques such as heteronuclear single quantum correlation (HSQC) or nuclear Overhauser effect spectroscopy (NOESY), but they are often cumbersome and require isotopic enrichment in nutrient-poor media. Fluorine (19F) NMR spectroscopy is a viable 1D alternative to 2D methods used for characterizing proteins, owing to both the excellent sensitivity of 19F and the much lower time cost it takes in running 1D versus 2D NMR experiments. The usefulness of 19F NMR is highlighted through two separate projects that reveal mechanistic insights into hnRNP H:G-tract molecular recognition. 19F is NMR active and is not found in essentially any biological system, making it suitable for studying protein-nucleic-acid interactions. 19F NMR spectroscopy can be coupled with paramagnetic relaxation enhancement (PRE), the effect of which can be measured in order to study non-specific interactions in a dynamic environment. Here, 19F NMR PREs are used in order to gain both qualitative and quantitative distance-dependent information about hnRNP H:G-tract binding (Chapter 2). 19F NMR spectroscopy can also be used to monitor changes in protein-RNA complexes resulting from drug binding as part of a larger screening pipeline dubbed “Targeting of (open full item for complete abstract)

Doctor of Philosophy (Ph.D.), Bowling Green State University, 2024, Philosophy

Advances in biomedical science have provided us with new and potent means of self-betterment that allow us to improve our capacities more quickly and effectively than ever before. I argue that these advances warrant a re-examination of our duties of self-improvement. My discussion of the ethics of enhancement has three primary objectives. First, I describe the duty of self-betterment and explain why biomedical enhancement is exceptionally well-suited to fulfill our duties of self-betterment Secondly, I compare hypothetical forms of biomedical enhancement to the practice of vaccination and argue that the arguments for our duty to be vaccinated are equally applicable to our duty to use other forms biomedical enhancement, especially when such enhancement helps us fulfill our Duty of Easy Rescue. Finally, I consider the impact that biomedical enhancement may have on the value of our achievements and respond to achievement-based objections to the use of biomedical enhancement. Ultimately, I conclude that biomedical enhancement is a reasonable, and sometimes required, means by which we can fulfill our duties of self-betterment, and deserves to be viewed more favorably in the future when considering means by which we might improve our capacities.

Doctor of Philosophy (Ph.D.), University of Dayton, 2023, Electro-Optics

This dissertation is concerned with two distinct applications of volume gratings recorded in photorefractive electro-optic crystals. The first of two applications involves the use of these volume gratings to non-mechanically steer laser beams. A geometric and physical-optics based analysis shows the potential for writing programmable volume gratings in lithium niobate using visible wavelengths in the transmission geometry, and subsequently probing those gratings using infrared wavelengths in a reflection geometry. By appropriate adjustments made to the writing beams, it is shown that both the grating spacing and grating tilt angle can be controlled such that the grating becomes a rotatable Bragg mirror for the incident probe beam, thus steering it to desired angles. The second application of these volume gratings is in image processing. System transfer functions determining the spatial evolution of the reference (input wave) and signal (diffracted wave) beams as they propagate inside a self-pumped volume reflection grating are derived and solved numerically. The solutions are then used to highlight the spatial filtering properties of self-pumped volume reflection gratings, with the focus being on the transmitted (un-diffracted) portion of the reference beam, which is shown to be high-pass spatially filtered. The high-pass spatial filtering manifests as programmable 2-dimensional edge enhancement in the transmitted reference beam. Contrast analysis is done for edge enhanced images, both through simulations and experiments, which show a direct proportionality between the strength of edge enhancement seen in the filtered images and the intensity of the writing beam used to record the grating.

MS, University of Cincinnati, 2023, Engineering and Applied Science: Mechanical Engineering

Wavy fin cores exhibit superior convective heat transfer performance over plain fins due to higher heat transfer surface area, waviness-induced swirl flow, and early inception of turbulence. There is an enhancement of heat transfer in both the laminar and turbulent regimes. In the continuous wavy channel, the waviness causes the flow to recirculate in the trough region, resulting in high local pressures at the flow reattachment locations. In the laminar regime, flow stagnation occurs at the recirculation zone in the trough region, which moderates the increase in heat transfer. In the turbulent regime, the heat transfer is improved because of flow recirculation, which aids in the turbulent mixing of the fluid. In continuous wavy fins, although the convective heat transfer is improved, the associated pressure drop penalty is also considerably higher than the plain fins. In the current study, modified wavy fins such as perforated and slotted wavy fins are investigated to better understand the potential to further improve the performance of wavy fins. The perforated wavy fins are produced through conventional methods of punching holes into aluminum sheet metal and then molding it into a wavy surface. In order to take full advantage of conventional manufacturing techniques, it is beneficial to invest time and resources to examine the performance of perforated wavy fins. A steady, periodically fully developed flow exposed to fin walls with uniform temperature is computationally modeled through perforated wavy fin cores. The computational model is validated by comparing numerical results for pressure drop and heat transfer for continuous wavy fins and perforated wavy fins with available experimental data where excellent agreement is observed. The model is then used to characterize the thermal-hydraulic performance of the air flows (Pr ≈ 0.71 and 50 ≤ Re ≤ 4000) in perforated wavy fin cores. The effect of the number of perforations on the performance of the perforated w (open full item for complete abstract)

Doctor of Philosophy (Ph.D.), University of Dayton, 2023, Electrical Engineering

This dissertation is comprised of two novel contributions. First, we propose a novel technique to determine the noise-free color at each pixel by estimating the ratio of the red, green, and blue (RGB) pixel values from their noisy version. In order to model the spatial statistics of the proportion of primary colors such as RGB components known to correspond to the human perception of color, we interpret the simplex representation of color as an Aitchison geometry. Specifically, we develop a minimum mean square error (MMSE) estimator of log-color pixel values in the wavelet representation, with Poisson as its pixel domain likelihood function. We contrast this to most existing denoising techniques that are predominantly designed for single-channel/greyscale images that are then applied to YCbCr channels independently without regard for the RGB proportionality. In the extremely low photon regime, we verify experimentally that the proposed method yields state-of-the-art color denoising performance. Second, we propose a novel image enhancement algorithm to assist with the automation of the quantification and characterization of fiber reinforced composite materials. The success of this Aitchison- and Noise2Noise-based enhancement algorithm allows for faster and more accurate classification of composite materials that are frequently used in aerospace systems. The enhancement algorithm is applied to X-ray/CT scans of composite materials and the resulting denoised frames are classified utilizing DRAGONFLY technology. It is found that the enhanced images are able to achieve superior classification accuracy as compared to unprocessed images.

Master of Science in Engineering, Youngstown State University, 2022, Department of Mechanical, Industrial and Manufacturing Engineering

Heat transfer enhancement studies were conducted on two main research areas in heat transfer. Those areas are fluid jet impingement and the use of porous mediums. Fluid jet impingement is a common heat transfer application in industry and is widely studied in research due to the high heat and mass transfer they provide. Porous mediums are another common engineering application that is typically found in heat exchangers and heat pipes due to the high heat transfer coefficient they produce. However, not much research stems from the combination of the two applications. By combining these two heat transfer applications, experiments were broken into two categories, non-boiling and boiling. Here, an apparatus was fabricated that allowed for both categories to be studied while allowing an inclination toward experimental plausibility. For the non-boiling experiment, flow rates were chosen that ranged from 4,000 ≤ Rew ≤ 11,000 under both free surface and submerged impinging jets. The goal was to determine the Nusselt number and compare the forced convection effect to the plain surface and porous mediums, i.e., monolayer wick and columnar post wick. Also, the variation in the Nusselt number was determined during lateral nozzle movement. The problems faced in pool boiling are the limited critical heat flux (CHF) and heat transfer coefficient (HTC) caused by the phase change over the heated surface. By employing the monolayer wick and columnar post wick, a decrease in the hydrodynamic instability (Rayleigh-Taylor) wavelength can occur, which provides heat transfer enhancements. To see if further heat transfer enhancements can be obtained, an impinging jet was added to the boiling apparatus with working flow rates of 800 ≤ Rew ≤ 1,700. Results for the non-boiling experiment show that the plain surface outperforms both monolayer wick and columnar post wick. This is due to the flow resistance present in both porous mediums. The rough surface of the monolayer wi (open full item for complete abstract)

Master of Science, The Ohio State University, 2022, Entomology

Mating induces a variety of physiological changes in female insects. These shifts can alter the immune capacity of the female, in some species positively and in some negatively. In mosquitoes, reproduction is decoupled into two parts: mating and blood feeding. Using Aedes aegypti as a model, we investigated how each of these components of reproduction affected the antibacterial immunity of females. We found that mating generally led to better survival of females infected with the bacterial pathogen Serratia marcescens compared to virgin females. Mating also significantly impacted prevalence of infection and bacterial load, but this was not observed in a subsequent experiment where we administered a lower initial dose. We additionally found that blood fed females, regardless of mating status, exhibited reduced survival following infection. We used qPCR to assess differences in transcript abundance for Defensin A (DefA), an antimicrobial peptide. We found that mating had no effect on constitutive transcript abundance of DefA nor on DefA transcript levels following infection, suggesting that other immune factors may be driving the observed increase in the immune competence of mated females.

Doctor of Philosophy, The Ohio State University, 2022, Speech and Hearing Science

The three manuscripts presented here examine concepts related to speech perception in noise and ways to overcome poor speech intelligibility without depriving listeners of environmental sound recognition. Because of hearing-impaired (HI) listeners' auditory deficits, there is a substantial need for speech-enhancement (noise reduction) technology. Recent advancements in deep learning have resulted in algorithms that significantly improve the intelligibility of speech in noise, but in order to be suitable for real-world applications such as hearing aids and cochlear implants, these algorithms must be causal, talker independent, corpus independent, and noise independent. Manuscript 1 involves human-subjects testing of a novel, time-domain-based algorithm that fulfills these fundamental requirements. Algorithm processing resulted in significant intelligibility improvements for both HI and normal-hearing (NH) listener groups in each signal-to-noise ratio (SNR) and noise type tested. In Manuscript 2, the range of speech-to-background ratios (SBRs) over which NH and HI listeners can accurately perform both speech and environmental recognition was determined. Separate groups of NH listeners were tested in conditions of selective and divided attention. A single group of HI listeners was tested in the divided attention experiment. Psychometric functions were generated for each listener group and task type. It was found that both NH and HI listeners are capable of high speech intelligibility and high environmental sound recognition over a range of speech-to-background ratios. The range and location of optimal speech-to-background ratios differed across NH and HI listeners. The optimal speech-to-background ratio also depended on the type of environmental sound present. Conventional deep-learning algorithms for speech enhancement target maximum intelligibly by removing as much noise as possible while maintaining the essential characteristics of the target speech signal (open full item for complete abstract)

Doctor of Philosophy (PhD), Ohio University, 2022, Experimental Psychology (Arts and Sciences)

Prior works (Kernis & Goldman, 2006; Maslow, 1971; Sedikides et al., 2019) characterize “authenticity” as the tendency to behave in a manner that aligns with one's authentic self. However, self-perceptions are often inaccurate and biased (Alicke, 1985; Brown, 2012; Ziano et al., 2021). In this dissertation, I propose an alternative framework whereby authenticity is marked by self-enhancement: authentic selves are idealized versions of selves. Five studies (N = 1529) found that authenticity perceptions were elicited when participants self-enhanced. In Study 1, future (vs. past) behaviors were perceived as being more representative of authentic selves, and this difference was smaller when judging others' authentic selves. Study 2 replicated and extended Study 1's findings in the context of moral behaviors by demonstrating that future selves were idealized, and that future selves were more representative of authentic selves than past selves. Study 3 replicated Study 2's results and additionally found that idealization rather than future expectations was most responsible for this difference. Study 4 further revealed that participants who idealized (vs. criticized) themselves experienced more state authenticity and meaning in life. Lastly, Study 5 found that, when asked to recall an authentic experience, participants engaged in self-enhancement, which then further positively predicted meaning in life and thriving. Together, the findings demonstrate that authenticity judgments are subject to self-enhancing tendencies and interpretations.s

Doctor of Philosophy, The Ohio State University, 2022, Chemical Engineering

Drag reduction (DR) by additives typically involves the use of either high molecular weight polymer or surfactants, and can reduce turbulent pressure losses in pipes by up to 90%. These additives, particularly high polymers, have seen considerable use in increasing the throughput of crude oil pipelines. Surfactant additives, while even more effective than their polymer cousins, have not seen widespread adoption despite their applicability to recirculating district heating or cooling networks. Due to their effects on the turbulent structure of pipe flow, drag reducing additives also result in the loss of radial mixing, and thus the suppression of convective heat transfer. This is referred to as the 'heat transfer reduction' (HTR) effect. Under normal conditions, drag reducing additives can reduce convective heat transfer in even greater amounts than they do turbulent pressure losses. Much of the recent research in the field of surfactant drag reduction has, therefore, been dedicated to the mitigation of heat transfer reduction. In this work, two projects are presented which successfully achieve this goal. In the first, a constricted heat exchanger is used to locally increase the shear stresses experienced by the working fluid. Simultaneously, a `weak' drag reducing solution comprised of quaternary ammonium salts with saturated tails 16 and 14 carbons in length and the counterion 3-chlorobenzoic acid. In conjunction with the constricted heat exchanger, this mixture is able to simultaneously generate high (>60%) DR and low (>30%) HTR over a range of flow rates and temperatures. Other unique properties of the system are examined, including switchability and hysteresis. The second study involves the design and application of 'gentle' static mixers. Rather than being designed to destroy the micellar structure thought to be responsible for DR, these mixers are intended to periodically disrupt the thermal boundary layer in the heat exchanger, thus improving heat tr (open full item for complete abstract)

Doctor of Philosophy, Case Western Reserve University, 2022, EECS - Electrical Engineering

This thesis shows that permanent magnets and electromechanical control systems can enable power-efficient, high-sensitivity, low-noise modalities for spectroscopy and wireless communication. Specifically I present two examples. The first is a radio frequency (RF) spectrometer which uses a detector cooled to 77 K to maximize measurement sensitivity, coupled with a minimally-intrusive network of active duplexers and mechanical contact switches to realize a reconfigurable series/parallel resonant network. I present a receiver which combines the highly sensitive analog frontend instrumentation with a mixed signal embedded system to monitor and control secondary processes. The cryogenic system increases the measurement signal to noise ratio (SNR) by a factor of 10×. The second example is an extremely low frequency (ELF) communication system which uses a mechanically-rotated dipole instead of an electrical antenna to generate the oscillating field of the transmitter. I show how a synchronous digital controller can maintain stable control over the dynamic process while a complementary embedded system modulates the set-point and monitors the channel. My transmitter achieves a power efficiency 7.6× greater than an equivalent electrical antenna in a device small enough to be moved by one person. I carry the transmitter into a cave and demonstrate cave-to-surface message transmission through 15 m of rock and frozen soil in a real-world field test. I present each solution in the context of scientific and human motivation, and explore tradeoffs required to achieve design goals. Emphasis is also placed on whether there exists a position of harmony and balance, where one may reasonably proclaim the optimum implementation has been achieved. The receiver is relatively more complex than the transmitter in the case of RF spectroscopy. In the case of ELF communication it is the reverse.

Doctor of Philosophy, The Ohio State University, 2022, Chemistry

Carr-Purcell-Meiboom-Gill (CPMG) echo train acquisition is commonly used in solid-state NMR to enhance its measurements' sensitivity when the lifetime of the signal is shortened by inhomo- geneous broadenings. The sensitivity gain that it provides depends on the echo train's coherence lifetime; thus, it's crucial to understand the factors that influence this lifetime to achieve the best sensitivity enhancements. Detailed in this thesis is an extensive investigation of 29Si's echo train coherence lifetime in silicate glasses. The origin of the 29Si echo train coherence lifetime decays was found to be dominated by residual dipolar couplings to alkali cation nuclei. Not only does this knowledge aid in improving the sensitivity of 29Si and facilitate the application of J coupling measurements, but it also has been used to show differences in the echo train coherence lifetimes between Q3 and Q4 sites indicate the presence of phase separation in alkali silicate glasses. This document also describes how the echo train coherence lifetime of the symmetric central (±1/2 → ∓1/2) transition of half-integer quadrupolar nuclei can be extended through the use of highly selective (low power) radio frequency pulses. For instance, I have shown that the echo train coherence lifetime of 17O in α-quartz can be extended by two orders of magnitude through the use of highly selective (low power) radio frequency pulses. This translates into enormous sensitivity gains for echo train acquisition schemes such as CPMG. By combining satellite population transfer schemes with a low power (2.73 kHz) CPMG on 17O in α-quartz, I have obtained over a 1000-fold sensitivity enhancement compared to a spectrum from a free induction decay acquired at a more typical rf field strength of 32.5 kHz. Additionally, I have determined higher power echo trains result in anisotropic lineshape distortions due to a disproportionate excitation of the crystallites' satellite transitions. A technical challenge with thi (open full item for complete abstract)