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Evaluating Sustainable Development Pathways for Protein- and Peptide-Based Bioadsorbents for Phosphorus Recovery from Wastewater
No full textRecovering phosphate (P) from point sources such as wastewater effluent is a priority in order to alleviate the impacts of eutrophication and implement a circular economy for an increasingly limited resource. Bioadsorbents featuring P-binding proteins and peptides offer exquisite P specificity and sensitivity for achieving ultralow P concentrations, i.e., <100 μg P L, a discharge limit that has been implemented in at least one treatment facility in nine U.S. states. To prioritize research objectives for P recovery in wastewater treatment, we compared the financial and environmental sustainability of protein/peptide bioadsorbents to those of LayneRT anion exchange resin. The baseline scenario (reflecting lab-demonstrated performance at a full-scale implementation) had costs that were 3 orders of magnitude higher than those for typical wastewater treatment. However, scenarios exploring bioadsorbent improvements, including increasing the P-binding capacity per unit volume by using smaller P-selective peptides and nanoparticle base materials and implementing reuse, dramatically decreased median impacts to 4.04 m and 0.19 kg CO equiv m. While the financial viability of capturing low P concentrations is a challenge, incorporating the externalities of environmental impacts may provide a feasible path forward to motivate ultralow P capture
Healing Far Afield
No full textWhat is the result of learning from place? After spending over a year visiting the KU Field Station, I consider our current relationship as humans with nature and propose the means for reframing it. My arts research studies our material entanglements with more-than-human others. Connection is fostered by attention, and connection contains the seeds of healing
Robust and Efficient Structure-Based Radar Receive Processing
No full textLegacy radar systems largely rely on repeated emission of a linear frequencymodulated (LFM) or chirp waveform to ascertain scattering information from an environment.The prevalence of these chirp waveforms largely stems from their simplicityto generate/process and robustness to physical hardware distortion. However,this traditional design philosophy may lack the flexibility and dimensionality neededto address the dynamic “complexification” of the modern radio frequency (RF) environmentor achieve current operational requirements where unprecedented degrees ofsensitivity, maneuverability, and adaptability are necessary.Over the last couple of decades analog-to-digital and digital-to-analog technologieshave advanced exponentially, resulting in tremendous design degrees of freedomand arbitrary waveform generation (AWG) capabilities that enable sophisticated designof emissions to better suit operational requirements. However, radar transmitters(TX) typically require high-power amplification (HPA) to contend with two-way propagationloss. Thus, transmitter-amenable waveforms are effectively constrained to beboth spectrally contained and constant amplitude, resulting in a non-convex NP-harddesign problem. While isolating the global optimal can be intractable for even modesttime-bandwidth products (TB), locally optimal TX-amenable solutions that are “goodenough” are often readily available. However, traditional matched filter (MF) basedestimation may no longer satisfy operational requirements with sub-optimal emissions.Using knowledge of the radar TX-to-receiver (TX-RX) chain, a discrete linearmodel can be formed to express the relationship between observed measurementsand the complex scattering of the environment. This structured representation enablesmore sophisticated least-square (LS) and adaptive estimation techniques that can designedto better satisfy operational requirements, improve estimate fidelity, and extenddynamic range. However, receive dimensionality can be enormous as the aggregatedegrees of freedom (DoF) for a coherent processing interval (CPI) is multiplicativewith respect to bandwidth, pulse duration, and number of pulses. Brute force implementationof model-based estimation techniques that leverage these DoFs may haveunwieldy computational burden on even the most cutting-edge signal processing hardware.Additionally, a discrete linear representation is fundamentally an approximationof a dynamic and continuous physical reality where model errors may induce bias, createfalse detections, or restrict effective dynamic range. As such, these structure-basedapproaches must be both computationally efficient and robust to reality.Here discrete receive models and algorithms for pulsed-radar range-Dopplerestimation are introduced. Modifications and alternative solutions are then proposedto improve estimate fidelity, reduce computational complexity, and enhance practicalrobustness
Multipass SAR Processing for Ice Sheet Vertical Velocity and Tomography Measurements
No full textVertical velocity is the rate at which ice moves vertically within an ice sheet, usually measured in meters per year. This movement can occur due to various factors, including accumulation, ice deformation, basal sliding, and subglacial melting. The measurement of vertical velocities within the ice sheet can assist in determining the age of the ice and assessing the rheology of the ice, thereby mitigating uncertainties due to analytical approximations in ice flow models.We apply differential interferometric synthetic aperture radar (DInSAR) techniques to data from the Multichannel Coherent Radar Depth Sounder (MCoRDS) to measure the vertical displacement of englacial layers within an ice sheet. DInSAR’s accuracy is usually on the order of a fraction of the wavelength (e.g., millimeter to centimeter precision is typical) in monitoring displacement along the radar line of sight (LOS). Ground-based Autonomous phase-sensitive Radio-Echo Sounder (ApRES) units have demonstrated the ability to precisely measure the relative vertical velocity by taking multiple measurements over time from the same location on the ice. Airborne systems can make a similar measurement but can suffer from deleterious spatial baseline effects since it is generally impossible to fly over the same stretch of ice on each pass with enough precision to ignore the spatial baseline. In this work, we compensate for spatial baseline errors using precise trajectory information and estimates of the cross-track layer slope using direction of arrival estimation. The current DInSAR algorithm is applied to airborne radar depth sounder data to produce results for flights near Summit Camp and the EGIG (Expéditions Glaciologiques Internationales au Groenland) line in Greenland. The existing approach estimates the parameters in multiple separated steps. However, each step has dependencies on all the values being estimated. To overcome this drawback, we have implemented a maximum likelihood estimator that jointly estimates the vertical velocity, the cross-track internal layer slope, and the unknown baseline error due to GPS and INS (Inertial Navigation System) errors. We incorporate the Lliboutry parametric model for vertical velocity into the maximum likelihood estimator framework.To improve the direction of arrival estimation of the internal layer slope, we also explore the use of focusing matrices against other wideband direction of arrival methods, such as wideband MLE, wideband MUSIC, and wideband MVDR, by comparing the mean squared error of the DOA estimates
Vertical Jump Neuromuscular Performance Characteristics Determining On-Court Contribution in Male and Female NCAA Division 1 Basketball Players
No full textWhile various quantifiable physical attributes have been found to contribute to athletes' performance, there is a lack of scientific literature focused on examining how they relate to success during competition performance. The aim of this study was to investigate different countermovement jump (CMJ)-derived force-time characteristics and their utility in distinguishing high from low performers within a measure of on-court contribution (i.e., minutes per game played). Twenty-nine collegiate athletes (n = 15 males and n = 14 females) volunteered to participate in this investigation and performed CMJs on dual force plates sampling at 1000 Hz, weekly over the course of their basketball season. The athletes' average of their three best test-days across the season was used for further analysis. To identify their on-court contribution, athletes were divided into groups with high and low minutes per game, based on a median-split analysis. The findings suggest that at the overall group level (i.e., both genders), the modified reactive strength index (mRSI) and braking rate of force development (RFD) revealed the greatest between-group magnitudes of difference, with athletes playing more minutes per game showing greater performance. At the team-specific level, the braking RFD, average braking velocity, and mRSI were shown to be the greatest differentiators between groups for the men's team. The women's high-minutes group displayed greater magnitudes of mRSI and jump height. By identifying the neuromuscular qualities seen in top performers within their respective populations, the attributed physical performance underpinning these qualities may be identified, providing practitioners with insights into physical performance qualities and training methodologies that have the potential to influence basketball performance
Recording Remote Attestations on the Blockchain
No full textRemote attestation is a process of establishing trust between various systems on a network. Until now, attestations had to be done on the fly as caching attestations had not yet been solved. With the blockchain providing a monotonic record, this work attempts to enable attestations to be cached. This paves the way for more complex attestation protocols to fit the wide variety of needs of users. We also developed specifications for these records to be cached on the blockchain
Functional inhibition of the RNA‐binding protein HuR sensitizes triple‐negative breast cancer to chemotherapy
No full textChemotherapy remains the standard treatment for triple‐negative breast cancer (TNBC); however, chemoresistance compromises its efficacy. The RNA‐binding protein Hu antigen R (HuR) could be a potential therapeutic target to enhance the chemotherapy efficacy. HuR is known to mainly stabilize its target mRNAs, and/or promote the translation of encoded proteins, which are implicated in multiple cancer hallmarks, including chemoresistance. In this study, a docetaxel‐resistant cell subline (231‐TR) was established from the human TNBC cell line MDA‐MB‐231. Both the parental and resistant cell lines exhibited similar sensitivity to the small molecule functional inhibitor of HuR, KH‐3. Docetaxel and KH‐3 combination therapy synergistically inhibited cell proliferation in TNBC cells and tumor growth in three animal models. KH‐3 downregulated the expression levels of HuR targets (e.g., β‐Catenin and BCL2) in a time‐ and dose‐dependent manner. Moreover, KH‐3 restored docetaxel's effects on activating Caspase‐3 and cleaving PARP in 231‐TR cells, induced apoptotic cell death, and caused S‐phase cell cycle arrest. Together, our findings suggest that HuR is a critical mediator of docetaxel resistance and provide a rationale for combining HuR inhibitors and chemotherapeutic agents to enhance chemotherapy efficacy
Evidence for Two Mechanisms to Account for the Speech to Song Illusion, the Verbal Transformation Effect, and the Sound to Music Illusion
Get PDFThis is an Accepted Manuscript of an article published by Taylor & Francis in Auditory Perception & Cognition on 25 Jul 2023, available at: https://doi.org/10.1080/25742442.2023.2240223.Introduction
Five studies examined the speech to song illusion, the verbal transformation effect, and the sound to music illusion in order to determine if they were distinct phenomena and to assess if they could be accounted for by a single perceptual/cognitive mechanism.
Methods
In Study 1, word lists varying in length from 1 word (as often used to study the verbal transformation effect) to 4 words (as often used to study the speech to song illusion) were presented to participants for 4 minutes to investigate the percepts that were elicited. In Study 2 participants were asked to indicate YES/NO if they experienced the speech to song illusion when listening to word-lists modified by a vocoder. In Studies 3–5 participants were asked to click a button as soon as the shift in percept occurred from speech (or sound) to a music-like percept to assess the time-course of the speech to song (or sound to music) illusion.
Results
Study 1 shows that the verbal transformation effect and the speech to song illusion elicit similar percepts. In Study 2 participants indicated that the speech-like stimuli elicited the speech to song illusion more than the noise-like stimuli. In Studies 3–5 similar time-courses were observed for the speech to song illusion and the sound to music illusion.
Discussion
Previous, single-mechanism accounts of the speech to song illusion are discussed, but none of them adequately account for all of the results presented here. A new model is proposed that appeals to both a perceptual/“lower-level” mechanism and a cognitive/“higher-level” mechanism
Linking Community Resilience to Health and Wellness
Get PDFCommunity Resilience (CR) is a topic on many people’s minds these days, and represents a community’s and an individual’s ability to weather adversity, as well as to adapt and recover. It also represents a community’s strength and readiness to respond to changes and capitalize on opportunities. Adaptation and recovery are intrinsically linked to the health and wellness of a community or individual, and measuring the link between CR and a community’s health is a point of key importance. Community resilience is complex, so scholars and stakeholders have developed a variety of models and metrics to measure and identify it. Many of these are linked to health and wellness outcomes within the community, providing a foundation for the link between the resilience of a community and the health of the people. Further research is required as the nature of CR is better defined, but current results provide support for using the measurement of CR to identify key points of intervention to improve the health and wellbeing of communities
Exploration of Conformity to Masculine Norms among Male Engineering Undergraduates
Get PDFThis study quantitatively examines the level to which college men studying engineering conform to masculine norms and the relationship between their conformity to masculine norms and sense of belonging in their major. Study participants were undergraduate, male-identifying students at a large, public research university in the Midwest. Masculine norm conformity was measured through the Conformity to Masculine Norms Inventory-46 (CMNI-46) and analyzed based on scores from each of the inventory’s nine subscales that align with nine popular masculine norms identified in Western culture. A comparison between engineering males’ masculine norm conformity scores and conformity scores from males enrolled in female-dominated majors at the same institution was also conducted.Results of the study indicate that engineering males in the study’s sample generally do not endorse the masculine norms measured by the CMNI-46. While the engineering males did indicate greater levels of conformity to the masculine norms compared to males in female-dominated majors, the differences were either statistically insignificant or very small. Masculine norm conformity scores were also found to predict only a small amount of the variance in scores measuring sense of belonging in major, indicating other variables not accounted for in the study are responsible for the majority of variance in belonging scores. This sample’s lack of endorsement of the masculine norms identified in the CMNI-46 align with other recent studies of similar populations and suggest that the norms measured by the instrument do not align with modern college males’ views of masculinity, suggesting that new approaches to masculinity research should be utilized for this population. Similarly, these findings suggest campus professionals should highlight positive expressions of masculinity when engaging in conversations about masculinity with men on campus