ABOUT THIS COLLECTION

This open access archive contains publications from University of Arizona faculty, researchers and staff, primarily open-access versions of formally published journal articles. The collection includes published articles and final accepted manuscripts submitted by UA faculty under the UA Open Access Policy. The collection also includes books, book chapters, book reviews, presentations, data, and other scholarly materials submitters have chosen to make available in the repository.


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Recent Submissions

  • Defect quantification in metal halide perovskites: the solid-state electrochemical alternative

    De Keersmaecker, Michel; Armstrong, Neal R.; Ratcliff, Erin L.; Department of Chemical and Environmental Engineering, The University of Arizona; Department of Chemistry and Biochemistry, The University of Arizona; Department of Materials Science and Engineering, The University of Arizona (Royal Society of Chemistry, 2021-07-24)
    Electrochemical methodologies are routinely used to determine energetics and defect density in semiconductor materials under operando conditions. For metal halide perovskites, electrochemical methods are restricted to a limited group of non-solvent electrolytes. This challenge is circumvented via a ”peel and stick” solid electrolyte that can contain redox active species, is transparent to visible and X-ray photons for simultaneous characterizations, and can be removed for quantification of near-surface composition and energetics using photoelectron spectroscopies. Defects are qualified for both near-stoichiometric and over-stoichiometric MAPbI3 films using controlled hole and electron injection, afforded through potential modulation with respect to a calibrated internal reference. Inclusion of mid-gap redox probes (ferrocene) allows for probing density of states, whereby electron transfer reversibility is shown to be dependent upon the number of ionized defects at the perovskite's band edges. A detailed Coulombic analysis is provided for determination of defect energetics and densities, with a near-stoichiometric film exhibiting a defect density of ∼2 × 1017 cm−3 at 0.1 eV above the valence band. We predict that this easily implemented three-electrode platform will be translatable to operando characterization of a range of semiconductor materials, including thin film perovskites, (in)organic semiconductors, quantum dots, and device stacks, where the removable solid electrolyte functions as the “top contact”.
  • Comprehensive Degree Based Key Node Recognition Method in Complex Networks

    Xie, Lixia; Sun, Honghong; Yang, Hongyu; Zhang, Liang; School of Information, University of Arizona (Springer International Publishing, 2021-09-17)
    Aiming at the problem of the insufficient resolution and accuracy of the key node recognition methods in complex networks, a Comprehensive Degree Based Key Node Recognition Method (CDKNR) in complex networks is proposed. Firstly, the K-shell method is adopted to layer the network and obtain the K-shell (Ks) value of each node, and the influence of the global structure of the network is measured by the Ks value. Secondly, the concept of Comprehensive Degree (CD) is proposed, and a dynamically adjustable influence coefficient μi is set, and the Comprehensive Degree of each node is obtained by measuring the influence of the local structure of the network through the number of neighboring nodes and sub-neighboring nodes and influence coefficient μi. Finally, the importance of nodes is distinguished according to the Comprehensive Degree. Compared with several classical methods and risk assessment method, the experimental results show that the proposed method can effectively identify the key nodes, and has high accuracy and resolution in different complex networks. In addition, the CDKNR can provide a basis for risk assessment of network nodes, important node protection and risk disposal priority ranking of nodes in the network.
  • A two-step resin based approach to reveal survivin-selective fluorescent probes

    Ambrose, A.J.; Pham, N.T.; Sivinski, J.; Guimarães, L.; Mollasalehi, N.; Jimenez, P.; Abad, M.A.; Jeyaprakash, A.A.; Shave, S.; Costa-Lotufo, L.V.; et al. (Royal Society of Chemistry, 2021)
    The identification of modulators for proteins without assayable biochemical activity remains a challenge in chemical biology. The presented approach adapts a high-throughput fluorescence binding assay and functional chromatography, two protein-resin technologies, enabling the discovery and isolation of fluorescent natural product probes that target proteins independently of biochemical function. The resulting probes also suggest targetable pockets for lead discovery. Using human survivin as a model, we demonstrate this method with the discovery of members of the prodiginine family as fluorescent probes to the cancer target survivin. This journal is © The Royal Society of Chemistry.
  • A Review of Recent Work in Transfer Learning and Domain Adaptation for Natural Language Processing of Electronic Health Records

    Laparra, E.; Mascio, A.; Velupillai, S.; Miller, T.; School of Information, University of Arizona (Thieme, 2021)
    OBJECTIVES: We survey recent work in biomedical NLP on building more adaptable or generalizable models, with a focus on work dealing with electronic health record (EHR) texts, to better understand recent trends in this area and identify opportunities for future research. METHODS: We searched PubMed, the Institute of Electrical and Electronics Engineers (IEEE), the Association for Computational Linguistics (ACL) anthology, the Association for the Advancement of Artificial Intelligence (AAAI) proceedings, and Google Scholar for the years 2018-2020. We reviewed abstracts to identify the most relevant and impactful work, and manually extracted data points from each of these papers to characterize the types of methods and tasks that were studied, in which clinical domains, and current state-of-the-art results. RESULTS: The ubiquity of pre-trained transformers in clinical NLP research has contributed to an increase in domain adaptation and generalization-focused work that uses these models as the key component. Most recently, work has started to train biomedical transformers and to extend the fine-tuning process with additional domain adaptation techniques. We also highlight recent research in cross-lingual adaptation, as a special case of adaptation. CONCLUSIONS: While pre-trained transformer models have led to some large performance improvements, general domain pre-training does not always transfer adequately to the clinical domain due to its highly specialized language. There is also much work to be done in showing that the gains obtained by pre-trained transformers are beneficial in real world use cases. The amount of work in domain adaptation and transfer learning is limited by dataset availability and creating datasets for new domains is challenging. The growing body of research in languages other than English is encouraging, and more collaboration between researchers across the language divide would likely accelerate progress in non-English clinical NLP. IMIA and Thieme. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.
  • Co-axial depth sensor with an extended depth range for AR/VR applications

    Xu, M.; Hua, H.; Visualization and Imaging Systems Laboratory, College of Optical Sciences, University of Arizona (KeAi Communications Co., 2020)
    Background: Depth sensor is an essential element in virtual and augmented reality devices to digitalize users' environment in real time. The current popular technologies include the stereo, structured light, and Time-of-Flight (ToF). The stereo and structured light method require a baseline separation between multiple sensors for depth sensing, and both suffer from a limited measurement range. The ToF depth sensors have the largest depth range but the lowest depth map resolution. To overcome these problems, we propose a co-axial depth map sensor which is potentially more compact and cost-effective than conventional structured light depth cameras. Meanwhile, it can extend the depth range while maintaining a high depth map resolution. Also, it provides a high-resolution 2D image along with the 3D depth map. Methods: This depth sensor is constructed with a projection path and an imaging path. Those two paths are combined by a beamsplitter for a co-axial design. In the projection path, a cylindrical lens is inserted to add extra power in one direction which creates an astigmatic pattern. For depth measurement, the astigmatic pattern is projected onto the test scene, and then the depth information can be calculated from the contrast change of the reflected pattern image in two orthogonal directions. To extend the depth measurement range, we use an electronically focus tunable lens at the system stop and tune the power to implement an extended depth range without compromising depth resolution. Results: In the depth measurement simulation, we project a resolution target onto a white screen which is moving along the optical axis and then tune the focus tunable lens power for three depth measurement subranges, namely, near, middle and far. In each sub-range, as the test screen moves away from the depth sensor, the horizontal contrast keeps increasing while the vertical contrast keeps decreasing in the reflected image. Therefore, the depth information can be obtained by computing the contrast ratio between features in orthogonal directions. Conclusions: The proposed depth map sensor could implement depth measurement for an extended depth range with a co-axial design. © 2019 Beijing Zhongke Journal Publishing Co. Ltd
  • An electrochemical biosensor platform for rapid immunoanalysis of physiological fluids

    Punj, S.; Sidhu, D.; Bhattacharya, D.; Wang, M.; Wong, P.K.; Department of Systems and Industrial Engineering, University of Arizona; Department of Ophthalmology and Vision Science, University of Arizona (Institute of Electrical and Electronics Engineers Inc., 2020)
    Cytokines are multifunctional chemical messengers produced in response to stimuli for regulating the innate and adaptive immune systems. Rapid detection of cytokines in physiological fluids will enable precision management of diseases, such as dry eye, postoperative infections, graft versus host reactions in organ transplant, and cancer. In this study, we present a portable electrochemical biosensor with electrokinetic enhancement for rapid detection of interleukin-6 in conductive fluids, including phosphate buffered saline, contrived tears, and human blood plasma. The multiplex electrochemical biosensor incorporates self-assembled monolayers and an enzymatic amplification cycle to achieve sensitive and specific detection of cytokine biomarkers. We establish electrokinetic enhancement by Joule-heating induced temperature rise and electrothermal fluid motion on the sensor surface for enhancing molecular advection and reaction kinetics, which overcomes major limiting factors of point-of-care immunoanalysis systems. By investigating the thermal and electrochemical characteristics of the system, we optimize the assay time and the signal-to-noise ratio of the biosensor for rapid immunoanalysis of physiological fluids. With its effectiveness and outstanding performance, the electrokinetics enhanced electrochemical biosensor provides a versatile platform for rapid immunoanalysis valuable for precision disease diagnosis and monitoring. © IEEE 2020.
  • Modeling hydrologic responses using multi-site and single-site rainfall generators in a semi-arid watershed

    Zhao, Y.; Nearing, M.A.; Guertin, D.P.; School of Natural Resources and the Environment, University of Arizona (International Research and Training Center on Erosion and Sedimentation and China Water and Power Press, 2021)
    Hydrologic response in a watershed is driven by precipitation. Multi-site rainfall generators can be used to model watersheds using spatially varied rainfall inputs to better analyze how the rainfall variability affects runoff generation. This study adopted both a single-site rainfall generator (CLIGEN) and a multi-site rainfall generator to generate two rainfall data sequences, which were then used to drive the Soil and Water Assessment Tool (SWAT) for runoff simulation. The 148-km2 Walnut Gulch Experimental Watershed and its two sub-watersheds were selected to evaluate the hydrologic response. Runoff calibration was done against measured runoff in the watershed. Statistics showed that the single-site and multi-site rainfall generators gave similar results regarding annual precipitation. However, the multi-site generator performed much better than the single-site generator in both mean summer flow and for the different return period flows. The runoff derived from the single-site generator was significantly over-estimated in all three watersheds. As for the multi-site generator, the derived runoff was satisfactorily predicted in the smaller watersheds but only overestimated in the largest watershed. This indicated that in small to medium sized watersheds, the spatial variability of rainfall could play an important role for hydrologic response because of the heterogeneity of convective rainfall in this semi-arid region, which makes the application of multi-site rainfall generator a better option than the single-site generator. © 2021 International Research and Training Center on Erosion and Sedimentation, China Water & Power Press
  • Extension Administrators' Perspectives on Employee Competencies and Characteristics

    Elliott-Engel, J.; Westfall-Rudd, D.; seibel, M.; Kaufman, E.; Radhakrishna, R.; University of Arizona (Extension Journal, Inc., 2021)
    Extension administrators discussed the competencies and characteristics of Extension professionals as they explored how Extension will need adapt to changing clientele, both in who they are and how they want to receive information. Extension education curriculum is not fully preparing future Extension employees in all required competencies, falling short on use of technology, diversity and pluralism, volunteer development, marketing, and public relations, risk management, and the community development process. Additionally, the Extension educator workforce development pipeline is not preparing a demographically representative population, leaving state administrators struggling to hire prepared professionals, especially those with in-culture competency (e.g., racial and ethnic minority and urban). © 2021. All Rights Reserved.
  • Ultimate limits of approximate unambiguous discrimination

    Zhuang, Q.; Department of Electrical and Computer Engineering, University of Arizona; James C. Wyant College of Optical Sciences, University of Arizona (American Physical Society, 2020)
    Quantum hypothesis testing is an important tool for quantum information processing. Two main strategies have been widely adopted: in a minimum error discrimination strategy, the average error probability is minimized; while in an unambiguous discrimination strategy, an inconclusive decision (abstention) is allowed to vanish any possibility of errors when a conclusive result is obtained. In both scenarios, the testing between quantum states is relatively well understood, for example, the ultimate limits of the performance are established decades ago; however, the testing between quantum channels is less understood. Although the ultimate limit of minimum error discrimination between channels has been explored recently, the corresponding limit of unambiguous discrimination is unknown. In this paper, we formulate an approximate unambiguous discrimination scenario, and derive the ultimate limits of the performance for both states and channels. In particular, in the channel case, our lower bound of the inconclusive probability holds for arbitrary adaptive sensing protocols. For the special class of "teleportation-covariant"channels, the lower bound is achievable with maximum entangled inputs and no adaptive strategy is necessary. © 2020 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
  • 4-H Youth Development Programming in Indigenous Communities: A Critical Review of Cooperative Extension Literature

    Farella, J.; Hauser, M.; Parrott, A.; Moore, J.D.; Penrod, M.; Elliott-Engel, J.; University of Arizona (Extension Journal, Inc., 2021)
    A literature review was conducted using the key words relating to Native American Youth and 4-H to assess the current state of 4-H youth programming serving First Nation/ Indigenous populations to inform future Extension initiatives. A systematic and qualitative review determined what level of focus the conducted programming efforts placed on broadly accepted elements of cultural identity as noted in the Peoplehood Model. A very small number of articles (N=13) were found pertaining to 4-H and Indigenous Communities. Fewer demonstrated emphasis on the peoplehood elements of language, place, traditional ceremony or calendars, and history. This work investigates a continuing inequity in 4-H PYD-both in service and reporting-and suggests some next steps for creating a more inclusive 4-H program for Native American/First Nation/Indigenous youth. © 2021. All Rights Reserved.
  • Sharing and Commenting Facilitate Political Learning on Facebook: Evidence From a Two-Wave Panel Study

    Kim, D.H.; Weeks, B.E.; Lane, D.S.; Hahn, L.B.; Kwak, N.; University of Arizona (SAGE Publications Ltd, 2021)
    Social media, as sources of political news and sites of political discussion, may be novel environments for political learning. Many early reports, however, failed to find that social media use promotes gains in political knowledge. Prior research has not yet fully explored the possibility based on the communication mediation model that exposure to political information on social media facilitates political expression, which may subsequently encourage political learning. We find support for this mediation model in the context of Facebook by analyzing a two-wave survey prior to the 2016 U.S. presidential election. In particular, sharing and commenting, not liking or opinion posting, may facilitate political knowledge gains. © The Author(s) 2021.
  • Entanglement-enhanced estimation of a parameter embedded in multiple phases

    Grace, M.R.; Gagatsos, C.N.; Guha, S.; James C. Wyant College of Optical Sciences, University of Arizona (American Physical Society, 2021)
    Quantum-enhanced sensing promises to improve the performance of sensing tasks using nonclassical probes and measurements that require far fewer scene-modulated photons than the best classical schemes, thereby granting previously inaccessible information about a wide range of physical systems. We propose a generalized distributed sensing framework that uses an entangled quantum probe to estimate a scene-parameter encoded within an array of phases, with a functional dependence on that parameter determined by the physics of the actual system. The receiver uses a laser light source enhanced by quantum-entangled multipartite squeezed-vacuum light to probe the phases and thereby estimate the desired scene-parameter. The entanglement suppresses the collective quantum vacuum noise across the phase array. We report simple analytical expressions for the Cramér-Rao bound that depend only on the optical probes and the physical model of the measured system, and we show that our structured receiver asymptotically saturates the quantum Cramér-Rao bound in the lossless case. Our approach enables Heisenberg limited precision in estimating a scene-parameter with respect to total probe energy, as well as with respect to the number of modulated phases. Furthermore, we study the impact of uniform loss in our system and examine the behavior of both the quantum and the classical Cramér-Rao bounds. We apply our framework to examples as diverse as radio-frequency phased-Array directional radar, beam-displacement tracking for atomic-force microscopy, and fiber-based temperature gradiometry. © 2021 authors. Published by the American Physical Society.
  • Oxidation-enhanced thermoelectric efficiency in a two-dimensional phosphorene oxide

    Lee, S.; Song, J.-P.; Kang, S.-H.; Kwon, Y.-K.; Department of Physics, University of Arizona (Nature Research, 2021)
    We performed density functional theory calculations to investigate the thermoelectric properties of phosphorene oxide (PO) expected to form by spontaneous oxidation of phosphorene. Since thermoelectric features by nature arise from the consequences of the electron-phonon interaction, we computed the phonon-mediated electron relaxation time, which was fed into the semiclassical Boltzmann transport equation to be solved for various thermoelectric-related quantities. It was found that PO exhibits superior thermoelectric performance compared with its pristine counterpart, which has been proposed to be a candidate for the use of future thermoelectric applications. We revealed that spontaneous oxidation of phosphorene leads to a significant enhancement in the thermoelectric properties of n-doped phosphorene oxide, which is attributed to the considerable reduction of lattice thermal conductivity albeit a small decrease in electrical conductivity. Our results suggest that controlling oxidation may be utilized to improve thermoelectric performance in nanostructures, and PO can be a promising candidate for low-dimensional thermoelectric devices. © 2021, The Author(s).
  • High- And low-latitude forcings drive Atacama Desert rainfall variations over the past 16,000 years

    González-Pinilla, F.J.; Latorre, C.; Rojas, M.; Houston, J.; Rocuant, M.I.; Maldonado, A.; Santoro, C.M.; Quade, J.; Betancourt, J.L.; Department of Geosciences, University of Arizona (American Association for the Advancement of Science, 2021)
    Late Quaternary precipitation dynamics in the central Andes have been linked to both high- and low-latitude atmospheric teleconnections. We use present-day relationships between fecal pellet diameters from ashy chinchilla rats (Abrocoma cinerea) and mean annual rainfall to reconstruct the timing and magnitude of pluvials (wet episodes) spanning the past 16,000 years in the Atacama Desert based on 81 14C-dated A. cinerea paleomiddens. A transient climate simulation shows that pluvials identified at 15.9 to 14.8, 13.0 to 8.6, and 8.1 to 7.6 ka B.P. can be linked to North Atlantic (high-latitude) forcing (e.g., Heinrich Stadial 1, Younger Dryas, and Bond cold events). Holocene pluvials at 5.0 to 4.6, 3.2 to 2.1, and 1.4 to 0.7 ka B.P. are not simulated, implying low-latitude internal variability forcing (i.e., ENSO regime shifts). These results help constrain future central Andean hydroclimatic variability and hold promise for reconstructing past climates from rodent middens in desert ecosystems worldwide. Copyright © 2021 The Authors, some rights reserved;
  • Early middle stone age personal ornaments from Bizmoune Cave, Essaouira, Morocco

    Sehasseh, E.M.; Fernandez, P.; Kuhn, S.; Stiner, M.; Mentzer, S.; Colarossi, D.; Clark, A.; Lanoe, F.; Pailes, M.; Hoffmann, D.; et al. (American Association for the Advancement of Science, 2021)
    Ornaments such as beads are among the earliest signs of symbolic behavior among human ancestors. Their appearance signals important developments in both cognition and social relations. This paper describes and presents contextual information for 33 shell beads from Bizmoune Cave (southwest Morocco). Many of the beads come as deposits dating to ≥142 thousand years, making them the oldest shell beads yet recovered. They extend the dates for the first appearance of this behavior into the late Middle Pleistocene. The ages and ubiquity of beads in Middle Stone Age (MSA) sites in North Africa provide further evidence of the potential importance of these artifacts as signals of identity. The early and continued use of Tritia gibbosula and other material culture traits also suggest a remarkable degree of cultural continuity among early MSA Homo sapiens groups across North Africa. Copyright © 2021 The Authors, some rights reserved;
  • Clinical pharmacy definition, required education, training and practice in Saudi Arabia: A position statement by the Saudi society of clinical pharmacy

    Korayem, G.B.; Badreldin, H.A.; Eljaaly, K.; Aldemerdash, A.; Al-Suhaibani, L.K.; Joharji, H.; Aljuhani, O.; Al-Omari, B.A.; Almudaiheem, H.Y.; Alhifany, A.A.; et al. (Elsevier B.V., 2021)
    The Saudi Society of Clinical Pharmacy (SSCP) is a scientific and professional society in the field of clinical pharmacy that operates under the Saudi Commission for Health Specialties governance. The SSCP believes that there is a need to define and describe many aspects related to the clinical pharmacy profession in Saudi Arabia. Moreover, there is an increasing demand for promoting the concept of clinical pharmacy and developing a consensus regarding the scope of practice and clinical pharmacist's required postgraduate education and training in Saudi Arabia. This paper is intended to present several position statements by the SSCP that define the concept of clinical pharmacy, describe the required education and training, and highlight clinical pharmacists' scope of practice in Saudi Arabia. This paper calls for further investigations that examine the impact of clinical pharmacists on individual and population health levels. © 2021 The Author(s)
  • Effects of political versus expert messaging on vaccination intentions of Trump voters

    Robertson, C.T.; Bentele, K.; Meyerson, B.; Wood, A.S.A.; Salwa, J.; College of Social and Behavioral Sciences, University of Arizona; University of Arizona (Public Library of Science, 2021)
    To increase COVID-19 vaccine uptake in resistant populations, such as Republicans, focus groups suggest that it is best to de-politicize the issue by sharing five facts from a public health expert. Yet polls suggest that Trump voters trust former President Donald Trump for medical advice more than they trust experts. We conducted an online, randomized, national experiment among 387 non-vaccinated Trump voters, using two brief audiovisual artifacts from Spring 2021, either facts delivered by an expert versus political claims delivered by President Trump. Relative to the control group, Trump voters who viewed the video of Trump endorsing the vaccine were 85% more likely to answer “yes” as opposed to “no” in their intention to get fully vaccinated (RRR = 1.85, 95% CI 1.01 to 3.40; P = .048). There were no significant differences between those hearing the public health expert excerpt and the control group (for “yes” relative to “no” RRR = 1.14, 95% CI 0.61 to 2.12; P = .68). These findings suggest that a political speaker’s endorsement of the COVID-19 vaccine may increase uptake among those who identify with that speaker. Contrary to highly-publicized focus group findings, our randomized experiment found that an expert’s factually accurate message may not be effectual to increase vaccination intentions. © 2021 Robertson et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
  • Investigating the relationship between (3200) phaethon and (155140) 2005 UD through telescopic and laboratory studies

    Kareta, T.; Reddy, V.; Pearson, N.; Sanchez, J.A.; Harris, W.M.; Lunar and Planetary Laboratory, University of Arizona (Web Portal IOP, 2021)
    The relationship between the near-Earth objects (3200) Phaethon and (155140) 2005 UD is unclear. While both are parents to meteor showers (the Geminids and Daytime Sextantids, respectively) and have similar visiblewavelength reflectance spectra and orbits, dynamical investigations have failed to find any likely method to link the two objects in the recent past. Here we present the first near-infrared reflectance spectrum of 2005 UD, which shows it to be consistently linear and red-sloped, unlike Phaethon's very blue and concave spectrum. Searching for a process that could alter some common starting material to both of these end states, we hypothesized that the two objects had been heated to different extents, motivated by their near-Sun orbits, the composition of Geminid meteoroids, and previous models of Phaethon's surface. We thus set about building a new laboratory apparatus to acquire reflectance spectra of meteoritic samples after heating to higher temperatures than available in the literature to test this hypothesis and were loaned a sample of the CI chondrite Orgueil from the Vatican Meteorite Collection for testing. We find that while Phaethon's spectrum shares many similarities with different CI chondrites, 2005 UD's does not. We thus conclude that the most likely relationship between the two objects is that their similar properties are only by coincidence as opposed to a parent-fragment scenario, though the ultimate test will be when JAXA's DESTINY+ mission visits one or both of the objects later this decade. We also discuss possible paths forward to understanding Phaethon's properties from dynamical and compositional grounds. © 2021. The Author(s).
  • New constraints on pluto's sputnik planitia ice sheet from a coupled reorientation-climate model

    Johnson, P.E.; Keane, J.T.; Young, L.A.; Matsuyama, I.; Lunar and Planetary Laboratory, University of Arizona (Web Portal IOP, 2021)
    We present a coupled reorientation and climate model, to understand how true polar wander (TPW) and atmospheric condensation worked together to create the Sputnik Planitia (SP) ice sheet and reorient it to its presentday location on Pluto. SP is located at 18°N, 178°E, very close to the anti-Charon point, and it has been previously shown that this location can be explained by TPW reorientation of an impact basin as it fills with N2 ice. We readdress that hypothesis while including a more accurate treatment of Pluto's climate and orbital obliquity cycle. Our model again finds that TPW is a viable mechanism for the formation and present-day location of SP. We find that the initial impact basin could have been located north of the present-day location, at latitudes between 35°N and 50°N. The empty basin is constrained to be 2.5-3 km deep, with enough N2 available to form at most a 1-2 km thick ice sheet. Larger N2 inventories reorient too close to the anti-Charon point. After reaching the final location, the ice sheet undergoes short periods of sublimation and recondensation on the order of 10 m of ice, due to Pluto's variable obliquity cycle, which drives short periods of reorientation of a few kilometers. The obliquity cycle also has a role in the onset of infilling; some initial basin locations are only able to begin accumulating N2 ice at certain points during the obliquity cycle. We also explore the sensitivity of the coupled model to albedo, initial obliquity, and Pluto's orbit. © 2021. The Author(s).
  • Randomized trial of the feasibility of ED-initiated school-based asthma medication supervision (ED-SAMS)

    Gerald, L.B.; Gerald, J.K.; VanBuren, J.M.; Lowe, A.; Guthrie, C.C.; Klein, E.J.; Morrison, A.; Startup, E.; Denninghoff, K.; University of Arizona (BioMed Central Ltd, 2021)
    Background: While using an inhaled corticosteroid (ICS) in the weeks after an ED visit reduces repeat visits, few children receive a needed prescription. Because a prescription may not be filled or used, dispensing ICS at discharge and supervising its use at school could overcome both barriers until follow-up care is established. To assess the feasibility of such an intervention, we conducted a pilot study among elementary-age school children with persistent asthma who were discharged from the ED following an asthma exacerbation. Methods: Eligible children were randomly assigned to ED-dispensing of ICS with home supervision or ED-dispensing of ICS with home and school supervision. The primary outcomes were ability to recruit and retain participants, ability to initiate school-supervised medication administration within 5 days of discharge, and participant satisfaction. Results: Despite identifying 437 potentially eligible children, only 13 (3%) were enrolled with 6 being randomized to the intervention group and 7 to the control group. Eleven (85%) randomized participants completed the 90-day interview (primary outcome) and 8 (62%) completed the 120-day interview (safety endpoint). Four (67%) intervention participants started their school regimen within 5 business days and 2 started within 6 business days. Conclusion: While our pilot study did not meet its recruitment goal, it did achieve its primary purpose of assessing feasibility before undertaking a larger, more intensive study. Several major recruitment barriers need to be mitigated before EDs can successfully partner with schools to establish supervised ICS treatment. Trial registration: ClinicalTrials.gov, NCT03952286. Registered 16 May 2019. © 2021, The Author(s).

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