Now showing items 1-20 of 93066

    • Alteration of fibrin hydrogel gelation and degradation kinetics through addition of azo dyes

      Gandhi, Jarel K; Heinrich, Lauren; Knoff, David S; Kim, Minkyu; Marmorstein, Alan D; Department of Biomedical Engineering, University of Arizona; Department of Materials Science, University of Arizona; BIO5 Institute, University of Arizona (Wiley, 2021-05-11)
      Fibrin is a degradable biopolymer with an excellent clinical safety profile. Use of higher mechanical strength fibrin hydrogels is limited by the rapid rate of fibrin polymerization. We recently demonstrated the use of higher mechanical strength (fibrinogen concentrations >30 mg/ml) fibrin scaffolds for surgical implantation of cells. The rapid polymerization of fibrin at fibrinogen concentrations impaired our ability to scale production of these fibrin scaffolds. We serendipitously discovered that the azo dye Trypan blue (TB) slowed fibrin gelation kinetics allowing for more uniform mixing of fibrinogen and thrombin at high concentrations. A screen of closely related compounds identified similar activity for Evans blue (EB), an isomer of TB. Both TB and EB exhibited a concentration dependent increase in clot time, though EB had a larger effect. While gelation time was increased by TB or EB, overall polymerization time was unaffected. Scanning electron microscopy showed similar surface topography, but transmission electron microscopy showed a higher cross-linking density for gels formed with TB or EB versus controls. Based on these data we conclude that addition of TB or EB during thrombin mediated fibrin polymerization slows the initial gelation time permitting generation of larger more uniform fibrin hydrogels with high-mechanical strength. © 2021 Wiley Periodicals LLC.
    • Thunderstorm and fair-weather quasi-static electric fields over land and ocean

      Wilson, Jennifer G.; Cummins, Kenneth L.; Department of Hydrology and Atmospheric Sciences, University of Arizona (Elsevier BV, 2021-08)
      Natural lightning and the associated clouds are known to behave differently over land and ocean, but many questions remain. We expand the related observational datasets by obtaining simultaneous quasi-static electric field observations over coastal land, near-shore water, and deep ocean regions during both fair-weather and thunderstorm periods. Oceanic observations were obtained using two 3-m NOAA buoys that were instrumented with Campbell Scientific electric field mills to measure the quasi-static electric fields. These data were compared to selected electric field records from the existing on-shore electric field mill suite of 31 sensors at Kennedy Space Center (KSC). Lightning occurrence times, locations and peak current estimates for both onshore and ocean were provided by the U.S. National Lightning Detection Network. The buoy instruments were first evaluated on-shore at the Florida coast, and the first system was calibrated for field enhancements and to confirm proper behavior of the system in elevated-field environments. The buoys were then moored 20 mi and 120 mi off the coast of KSC in February (20 mi) and August (120 mi) 2014. Diurnal fair-weather fields at both ocean sites matched will with each other and with those found during the Carnegie cruise, but mean values were 33% smaller, due at least in-part to constraints on the calibration procedure. Diurnal fair-weather fields variations at coastal and inland sites were a poorer match than offshore, likely because the offshore environment is “cleaner” with limited variations in local space charge, lower surface aerosol densities, little surface heating to disturb the surface charge layer during fair weather, and fewer local radioactive sources to modulate the near-surface electrical conductivity. Storm-related static fields were 4-5× larger at both oceanic sites than over land, likely due to decreased screening by near-surface space charge produced by corona current. The time-evolution of the electric field and field changes during storm approach are sufficiently different over land and ocean to warrant further study. This work shows the quality, accuracy, and reliability of these data, and has demonstrated the practicality of off-shore electric field measurements for safety- and launch-related decision making at KSC.
    • A Planet of Surplus Life: Building Worlds Beyond Capitalism

      Shaw, Ian G. R.; Waterstone, Marv; School of Geography, Development & Environment, University of Arizona (Wiley, 2021-05-19)
      Capitalism is an immense machine for churning out surplus life. Its long war of enclosure has captured, controlled, and pauperised human life, and laid waste to nonhuman life. This paper argues that surplus populations—people rendered as economically redundant—are central to the future politics of our planet. Yet the ruling classes still fight to preserve capitalism in all its horror: “you must work, even if there are no jobs!” How we diagnose this dilemma is a vital task of our age. We respond with a beyond-capitalist politics that challenges centuries of capitalist world-alienation, pauperism, and indignity. We present a radical alternative, centred on the interlocking ideas of alter-worlds, alter-work, and alter-politics. Each is based on building, sustaining, and connecting new spaces of geographic justice and autonomy for all. We must make the end of capitalism easier to imagine than the end of the world.
    • Investigation of thermal properties of crystalline alpha quartz by employing different interatomic potentials: A molecular dynamic study

      Molaei, Fatemeh; Moghadam, Mostafa Safdari; Nouri, Shahrzad; Mining and Geological Engineering Department, The University of Arizona (Elsevier BV, 2021-07)
      In the present work, the thermal properties of crystalline α-quartz, including thermal conductivity (TC) and thermal expansion coefficient (TEC), are studied using the non-equilibrium molecular dynamics (NEMD) simulation method. Since there is a dependence on interatomic potentials in simulation results, the thermal conductivity and thermal expansion coefficient of crystalline α- quartz is computed using various force fields in a temperature range from 200 K to 1000 K compare which concurs better with experimental findings. Arising from the present molecular dynamic simulation by different force fields such as Tersoff, Vashishta, Stillinger-Weber, Meam, BKS, ReaxFF, and Morse, the thermal conductivities that were carried out using the ReaxFF and BKS are more accurate. It is also founded that predicted thermal conductivity at higher temperatures shows a better agreement with experimental values. In terms of TEC, Tersoff and SW corroborate the experimental remarks and give a smaller magnitude of TEC in z direction. On the other hand, in contradiction with the other force fields, Meam potential presents no significant TEC variation with temperature alteration. © 2021 Elsevier B.V.
    • μ Opioid Antagonist Naltrexone Partially Abolishes the Antidepressant Placebo Effect and Reduces Orbitofrontal Cortex Encoding of Reinforcement

      Peciña, Marta; Chen, Jiazhou; Lyew, Thandi; Karp, Jordan F; Dombrovski, Alexandre Y; Department of Psychiatry, University of Arizona (Elsevier Inc., 2021-03-06)
      Background: Like placebo analgesia, the antidepressant placebo effect appears to involve cortical and subcortical endogenous opioid signaling, yet the mechanism through which opioid release affects mood remains unclear. The orbitofrontal cortex (OFC)—which integrates various attributes of a stimulus to predict associated outcomes—has been implicated in placebo effects and is rich in μ opioid receptors. We hypothesized that naltrexone blockade of μ opioid receptors would blunt OFC-dependent antidepressant placebo effects. Methods: Twenty psychotropic-free patients with major depressive disorder completed a randomized, double-blind, placebo-controlled crossover study of 1 oral dose of 50 mg of naltrexone or matching placebo immediately before completing 2 sessions of the antidepressant placebo functional magnetic resonance imaging task. This task manipulates placebo-associated expectancies and their reinforcement while assessing expected and actual mood improvement. Results: Behaviorally, manipulations of antidepressant placebo expectancies and their reinforcement had positive, interactive effects on participants’ expectancy and mood ratings. The high-expectancy condition recruited the dorsolateral and ventrolateral prefrontal cortex, as well as dorsal attention stream regions. Interestingly, increased dorsolateral and ventrolateral prefrontal cortex brain responses appeared to attenuate the antidepressant placebo effect. The administration of 1 oral dose of naltrexone, compared with placebo, partially abolished the interaction of the expectancy and reinforcement manipulation on mood and blocked reinforcement-induced responses in the right central OFC. Conclusions: Our results show preliminary evidence for the role of μ opioid central OFC modulation in antidepressant placebo effects by positively biasing the value of placebo based on reinforcement and enhancing subsequent hedonic experiences.
    • Imaging the dynamics and microstructure of fibrin clot polymerization in cardiac surgical patients using spectrally encoded confocal microscopy

      Tshikudi, Diane M; Simandoux, Olivier; Kang, Dongkyun; Van Cott, Elizabeth M; Andrawes, Michael N; Yelin, Dvir; Nadkarni, Seemantini K; College of Optical Sciences and Department of Biomedical Engineering, University of Arizona (John Wiley and Sons Inc, 2021-05-10)
      During cardiac surgery with cardiopulmonary bypass (CPB), altered hemostatic balance may disrupt fibrin assembly, predisposing patients to perioperative hemorrhage. We investigated the utility of a novel device termed spectrally-encoded confocal microscopy (SECM) for assessing fibrin clot polymerization following heparin and protamine administration in CPB patients. SECM is a novel, high-speed optical approach to visualize and quantify fibrin clot formation in three dimensions with high spatial resolution (1.0 μm) over a volumetric field-of-view (165 × 4000 × 36 μm). The measurement sensitivity of SECM was first determined using plasma samples from normal subjects spiked with heparin and protamine. Next, SECM was performed in plasma samples from patients on CPB to quantify the extent to which fibrin clot dynamics and microstructure were altered by CPB exposure. In spiked samples, prolonged fibrin time (4.4 ± 1.8 to 49.3 ± 16.8 min, p < 0.001) and diminished fibrin network density (0.079 ± 0.010 to 0.001 ± 0.002 A.U, p < 0.001) with increasing heparin concentration were reported by SECM. Furthermore, fibrin network density was not restored to baseline levels in protamine-treated samples. In CPB patients, SECM reported lower fibrin network density in protaminized samples (0.055 ± 0.01 A.U. [Arbitrary units]) vs baseline values (0.066 ± 0.009 A.U.) (p = 0.03) despite comparable fibrin time (baseline = 6.0 ± 1.3, protamine = 6.4 ± 1.6 min, p = 0.5). In these patients, additional metrics including fibrin heterogeneity, length and straightness were quantified. Note, SECM revealed that following protamine administration with CPB exposure, fibrin clots were more heterogeneous (baseline = 0.11 ± 0.02 A.U, protamine = 0.08 ± 0.01 A.U, p = 0.008) with straighter fibers (baseline = 0.918 ± 0.003A.U, protamine = 0.928 ± 0.0006A.U. p < 0.001). By providing the capability to rapidly visualize and quantify fibrin clot microstructure, SECM could furnish a new approach for assessing clot stability and hemostasis in cardiac surgical patients. © 2021 Wiley Periodicals LLC.
    • Exploiting the HSP60/10 chaperonin system as a chemotherapeutic target for colorectal cancer

      Ray, Anne-Marie; Salim, Nilshad; Stevens, Mckayla; Chitre, Siddhi; Abdeen, Sanofar; Washburn, Alex; Sivinski, Jared; O'Hagan, Heather M.; Chapman, Eli; Johnson, Steven M.; et al. (Elsevier BV, 2021-06)
      Over the past few decades, an increasing variety of molecular chaperones have been investigated for their role in tumorigenesis and as potential chemotherapeutic targets; however, the 60 kDa Heat Shock Protein (HSP60), along with its HSP10 co-chaperone, have received little attention in this regard. In the present study, we investigated two series of our previously developed inhibitors of the bacterial homolog of HSP60/10, called GroEL/ES, for their selective cytotoxicity to cancerous over non-cancerous colorectal cells. We further developed a third “hybrid” series of analogs to identify new candidates with superior properties than the two parent scaffolds. Using a series of well-established HSP60/10 biochemical screens and cell-viability assays, we identified 24 inhibitors (14%) that exhibited > 3-fold selectivity for targeting colorectal cancer over non-cancerous cells. Notably, cell viability EC50 results correlated with the relative expression of HSP60 in the mitochondria, suggesting a potential for this HSP60-targeting chemotherapeutic strategy as emerging evidence indicates that HSP60 is up-regulated in colorectal cancer tumors. Further examination of five lead candidates indicated their ability to inhibit the clonogenicity and migration of colorectal cancer cells. These promising results are the most thorough analysis and first reported instance of HSP60/10 inhibitors being able to selectively target colorectal cancer cells and highlight the potential of the HSP60/10 chaperonin system as a viable chemotherapeutic target.
    • Trade‐offs between weapons and testes do not manifest at high social densities

      Miller, Christine W.; Joseph, Paul N.; Emberts, Zachary; Department of Ecology and Evolutionary Biology, University of Arizona (Wiley, 2021-04-28)
      Social conditions can alter the allocation of resources to reproductive traits. For example, an increase in social density during development is frequently associated with an increase in the testes mass of males. Sperm competition theory assumes that increased investment in testes should come at the expense of investing into precopulatory traits, such as sexually selected weaponry. However, much remains unknown about the role of the social context on the concurrent, relative investment in both testes and weapons. We found that the leaf-footed cactus bug, Narnia femorata (Hemiptera: Coreidae), grew nearly 20% larger testes when raised in high social densities. In addition to manipulating social density, we used autotomy (limb loss) to limit investment in their hindlimb weapon during development. At low densities, we found that those that lost a weapon during development grew larger testes by adulthood, supporting previous work demonstrating a weapons–testes trade-off. However, at high social densities, males that dropped a hindlimb did not grow larger testes, though testes were already large at this density. These results underscore the importance of the social context to resource allocation patterns within the individual. © 2021 European Society for Evolutionary Biology
    • Gender Disparities in Cardiac Catheterization Rates Among Emergency Department Patients With Chest Pain

      Steenblik, Jacob; Smith, Alison; Bossart, Christopher S; Hamilton, David S; Rayner, Thomas; Fuller, Matthew; Carlson, Margaret; Madsen, Troy; Sarver Heart Center, University of Arizona (Lippincott Williams and Wilkins, 2021)
      Background: Previous studies have noted differences in rates of cardiac testing based on gender of patients. We evaluated cardiac catheterization rates for men and women presenting to the emergency department (ED) with chest pain, particularly among patients without a history of myocardial infarction (MI) or recent positive stress test. Methods: We performed a prospective evaluation of patients presenting to an urban, academic medical center for assessment of chest pain. We recorded baseline information, testing, and outcomes related to ED, observation unit, and inpatient stay. Primary outcomes included gender differences in cardiac catheterization and stenting rates among patients without an MI or positive stress test. Results: Over the 5.5 year study period, 2242 ED patients with chest pain participated in the study (45% male). Men and women had similar rates of cardiac stress testing (16.7% vs. 15.2%, P = 0.317) as well as similar rates of positive cardiac stress testing (2.9% vs. 1.9%, P = 0.116). Men were more likely to undergo cardiac catheterization (10.4% vs. 4.9%, P < 0.001). Men who had neither MI nor positive stress test were more likely than women to undergo cardiac catheterization: 5.8% versus 3.3%, P = 0.010. Similarly, men in this group were more likely to experience stent placement: 2.1% versus 0.7%, P = 0.003. Conclusions: Similar to previous studies, we noted disparities in cardiac testing by gender. Men were more likely to go to cardiac catheterization without an MI or a positive stress test. This disparity in a more aggressive strategy of cardiac catheterization in men may result in higher stenting rates in this group.
    • Role of city collaboration networks in the acceleration and attenuation of integrated water management

      Berger, Lena; Henry, Adam Douglas; Pivo, Gary; School of Government and Public Policy, University of Arizona; College of Architecture, Planning, and Landscape Architecture, University of Arizona (IWA Publishing, 2021-02-26)
      Inter-city collaboration has gained prominence as a strategy to share practical experience and accelerate the spread of novel sustainability practices. This study explores the potential of collaboration as a means to foster the uptake of integrated water management (IWM). IWM is an innovative approach to water management regarded as key to achieving urban water sustainability. The uptake of IWM has generally been slow due to organizational and institutional challenges. To explore the potential of collaboration to accelerate uptake, we analyze collaboration among 45 cities in Arizona, USA, relative to their IWM engagement and organizational capacity. We find that collaboration patterns reflect cities' interest in learning about innovative practices. However, there is a tendency to primarily collaborate with others who are in close geographic proximity. IWM practices and organizational capacities are secondary drivers of collaboration. Overall, our findings show opportunities while also urging realistic expectations. © 2021 The Authors
    • Precision Glass molding for diffractive optics

      Zhang, YingYing; Zhou, Wenchen; Spires, Oliver; Kim, Young Sik; Yi, Allen; Liang, Rongguang; Milster, Tom D.; Wyant College of Optical Sciences, University of Arizona (OSA, 2020)
      We proposed a comprehensive technical scheme addressing the fabrication limitation of diamond turning, coating stability and adhesion problem during molding process,to realize high performance of diffractive optics.
    • Development of Aquaculture Protocols and Gonadal Differentiation of Red Shiner

      Teal, Chad N.; Schill, Daniel J.; Fogelson, Susan B.; Bonar, Scott A.; Arizona Cooperative Fish and Wildlife Research Unit, School of Natural Resources and the Environment, University of Arizona (Wiley, 2021-06-03)
      Developing detailed rearing methods and describing the onset of gonadal differentiation in Red Shiners Cyprinella lutrensis could facilitate the development of novel techniques to control or enhance populations, enable toxicology studies, and help construct bioassays. In this study, we develop and report aquaculture practices for Red Shiner that ensure consistent year-round production in laboratory settings and evaluate the timing of sexual differentiation via histological gonad examinations. Our methods resulted in a mean of 56.00% (SD = 8.98%) survival through the larval stages of development, and we obtained spawns from captive-reared Red Shiners 138 d posthatch. Red Shiners are gonochoristic, and both ovaries and testes differentiate directly from undifferentiated gonads. Ovaries begin to differentiate in females 45 d posthatch, while testes begin differentiating in males 105 d posthatch. This study provides in-depth protocols for the closed-cycle aquaculture of Red Shiners and describes the gonadal differentiation and development of both sexes. © 2020 American Fisheries Society
    • Finding the self through others: exploring fandom, identification, and self-concept clarity among U.S. adolescents

      Dajches, Leah; Department of Communication, University of Arizona (Informa UK Limited, 2021-04-29)
      The primary developmental task of adolescence (12–18 years old) is identity development. During this time, adolescents individuate from their parents and may instead use media models for social guidance. Previous research has analyzed the impact of media figures on adolescents’ socialization but few have explored the influence of non-fiction media figures on their self-concept. As such, the present study examined of the role of fanship and identification on adolescent self-concept clarity. From a survey of 251 adolescents (ages 13–18), results showed that adolescents’ fanship intensity was negatively associated with their self-concept clarity. Further, identification did not moderate this association, but identification demonstrated a negative association with self-concept clarity. Impact summary Prior State of Knowledge: Previous research shows that media fandom may impact peoples’ ideological beliefs and behaviors (e.g., gender roles, prosocial behavior, overcoming adversity). Moreover, research finds that fandom engagement may benefit marginalized communities. Novel Contributions: The current project contributes to the media entertainment and fan studies literatures with a novel exploration of fandom and fan identification in relation to adolescents’ self-concept clarity. Specifically, fanship intensity and identification were negatively associated with self-concept clarity. Practical Implications: Parents should be aware of their child’s fanship intensity surrounding their favorite non-fiction media figure because such engagement may negatively influence their self-concept, which might contribute to difficulties in establishing a cohesive identity. © 2021 Informa UK Limited, trading as Taylor & Francis Group.
    • On the Readability of Abstract Set Visualizations

      Wallinger, Markus; Jacobsen, Ben; Kobourov, Stephen; Nollenburg, Martin; Dept. of Computer Science, University of Arizona (Institute of Electrical and Electronics Engineers (IEEE), 2021-06)
      Set systems are used to model data that naturally arises in many contexts: social networks have communities, musicians have genres, and patients have symptoms. Visualizations that accurately reflect the information in the underlying set system make it possible to identify the set elements, the sets themselves, and the relationships between the sets. In static contexts, such as print media or infographics, it is necessary to capture this information without the help of interactions. With this in mind, we consider three different systems for medium-sized set data, LineSets, EulerView, and MetroSets, and report the results of a controlled human-subjects experiment comparing their effectiveness. Specifically, we evaluate the performance, in terms of time and error, on tasks that cover the spectrum of static set-based tasks. We also collect and analyze qualitative data about the three different visualization systems. Our results include statistically significant differences, suggesting that MetroSets performs and scales better. © 1995-2012 IEEE.
    • The Fe/S ratio of pyrrhotite group sulfides in chondrites: An indicator of oxidation and implications for return samples from asteroids Ryugu and Bennu

      Schrader, Devin L.; Davidson, Jemma; McCoy, Timothy J.; Zega, Thomas J.; Russell, Sara S.; Domanik, Kenneth J.; King, Ashley J.; Lunar and Planetary Laboratory, University of Arizona (Elsevier BV, 2021-06)
      Determining compositional trends among individual minerals is key to understanding the thermodynamic conditions under which they formed and altered, and is also essential to maximizing the scientific value of small extraterrestrial samples, including returned samples and meteorites. Here we report the chemical compositions of Fe-sulfides, focusing on the pyrrhotite-group sulfides, which are ubiquitous in chondrites and are sensitive indicators of formation and alteration conditions in the protoplanetary disk and in small Solar System bodies. Our data show that while there are trends with the at.% Fe/S ratio of pyrrhotite with thermal and aqueous alteration in some meteorite groups, there is a universal trend between the Fe/S ratio and degree of oxidation. Relatively reducing conditions led to the formation of troilite during: (1) chondrule formation in the protoplanetary disk (i.e., pristine chondrites) and (2) parent body thermal alteration (i.e., LL4 to LL6, CR1, CM, and CY chondrites). Oxidizing and sulfidizing conditions led to the formation of Fe-depleted pyrrhotite with low Fe/S ratios during: (1) aqueous alteration (i.e., CM and CI chondrites), and (2) thermal alteration (i.e., CK and R chondrites). The presence of troilite in highly aqueously altered carbonaceous chondrites (e.g., CY, CR1, and some CM chondrites) indicates they were heated after aqueous alteration. The presence of troilite, Fe-depleted pyrrhotite, or pyrite in a chondrite can provide an estimate of the oxygen and sulfur fugacities at which it was formed or altered. The data reported here can be used to estimate the oxygen fugacity of formation and potentially the aqueous and/or thermal histories of sulfides in extraterrestrial samples, including those returned by the Hayabusa2 mission and due to be returned by the OSIRIS-REx mission in the near future. © 2021 The Author(s)
    • The Journey Home: Violence, Anchoring, and Refugee Decisions to Return

      Ghosn, Faten; Chu, Tiffany S.; Simon, Miranda; Braithwaite, Alex; Frith, Michael; Jandali, Joanna; School of Government and Public Policy, University of Arizona (Cambridge University Press (CUP), 2021-05-17)
      While the UNHCR promotes voluntary repatriation as the preferred solution to refugee situations, there is little understanding of variation in refugees' preferences regarding return. We develop a theoretical framework suggesting two mechanisms influencing refugees' preferences. First, refugees' lived experiences in their country of origin prior to displacement and in their new host country create a trade-off in feelings of being anchored to their origin or host country. Second, firsthand exposure to traumas of war provides some refugees with a sense of competency and self-efficacy, leading them to prefer to return home. We test these relationships with data from a survey among Syrian refugees hosted in Lebanon. We find refugees exposed to violence during the war have a sense of attachment to Syria and are most likely to prefer return. Refugees who have developed a detachment from Syria or an attachment to Lebanon are less likely to prefer return.
    • Recruiting Nurses Via Social Media for Survey Studies

      Bethel, Claire; Rainbow, Jessica G; Dudding, Katherine M; The University of Arizona (Lippincott Williams and Wilkins, 2021)
      Background: Nurses are a difficult population to recruit for research. Barriers to recruitment of nurses include survey fatigue, hospital structures and institutional review boards as gatekeepers to accessing participants, and limited generalizability of findings. Social media present innovative opportunities to recruit participants for survey research. However, there is limited information about best practices for recruiting nurses through social media. Objectives: The aim of this report was to examine the advantages and disadvantages of and determine the best practices for recruiting nurses for survey studies via social media. Methods: We examined recruitment strategies of three survey studies involving nurse participants. Each study used social exchange theory and leverage-saliency theory to guide recruitment. The studies included were (a) the Travel Nurse Onboarding Study, which recruited participants from a single closed group on Facebook; (b) the Presenteeism and Nursing Study where participants were recruited using association listservs, healthcare organizations, and paid ads and postings on social media; and (c) the Pain and Nursing Study in which participants were recruited through social media, association listservs, and in person at conferences. Results: Social media offer accessible, low-cost, high-yield approaches to recruitment of nurses for survey studies. Discussion Useful strategies for crafting effective recruitment via social media are presented, including how, where, when, and how often to post. The generalizability of social media research is also discussed. Suggestions are provided for researchers using social media as well as guidelines for institutional review boards to address gray areas of social media research. Data integrity protection techniques are proposed to ensure social media survey data are not corrupted by malicious bots. This report outlines best practices for the recruitment of nurses for survey studies using social media. © 2020 Wolters Kluwer Health, Inc. All rights reserved.
    • Teaching drunk: Work, the online economy, and uncertainty in action

      Kramer, Max F.; Department of Philosophy and Program in Cognitive Science, University of Arizona (Cambridge University Press (CUP), 2021-05-14)
      Technological developments have led to the digitization of certain sectors of the economy, and this has many authors looking ahead to the prospects of a post-work society. While it is valuable to theorize about this possibility, it is also important to take note of the present state of work. For better or worse, it is what we are currently stuck with, and as the COVID-19 pandemic has ensured, much of that work is now taking place online. Though a 'return to normalcy' is on the horizon, part of that normalcy involves online work, which is itself a significant change in the lives of many workers. Here I develop an account of work on which work is teleologically structured. This gives the result that working is something we can fail at doing, even when we try, and we can also be unsure of whether we've succeeded or failed. The shift of certain work from in-person to online modes generates a persistent uncertainty for workers in affected professions. Because our ability to work is something we typically value, this uncertainty has significant negative consequences for a worker's self-conception. Indeed, it is analogous to disorders of agency and generates a kind of alienation.
    • A megastudy of text-based nudges encouraging patients to get vaccinated at an upcoming doctor's appointment

      Milkman, Katherine L; Patel, Mitesh S; Gandhi, Linnea; Graci, Heather N; Gromet, Dena M; Ho, Hung; Kay, Joseph S; Lee, Timothy W; Akinola, Modupe; Beshears, John; et al. (National Academy of Sciences, 2021)
      Many Americans fail to get life-saving vaccines each year, and the availability of a vaccine for COVID-19 makes the challenge of encouraging vaccination more urgent than ever. We present a large field experiment (N = 47,306) testing 19 nudges delivered to patients via text message and designed to boost adoption of the influenza vaccine. Our findings suggest that text messages sent prior to a primary care visit can boost vaccination rates by an average of 5%. Overall, interventions performed better when they were 1) framed as reminders to get flu shots that were already reserved for the patient and 2) congruent with the sort of communications patients expected to receive from their healthcare provider (i.e., not surprising, casual, or interactive). The best-performing intervention in our study reminded patients twice to get their flu shot at their upcoming doctor's appointment and indicated it was reserved for them. This successful script could be used as a template for campaigns to encourage the adoption of life-saving vaccines, including against COVID-19.
    • Vascular deficiencies in renal organoids and ex vivo kidney organogenesis

      Ryan, Anne R; England, Alicia R; Chaney, Christopher P; Cowdin, Mitzy A; Hiltabidle, Max; Daniel, Edward; Gupta, Ashwani Kumar; Oxburgh, Leif; Carroll, Thomas J; Cleaver, Ondine; et al. (Elsevier Inc., 2021-05-15)
      Chronic kidney disease (CKD) and end stage renal disease (ESRD) are increasingly frequent and devastating conditions that have driven a surge in the need for kidney transplantation. A stark shortage of organs has fueled interest in generating viable replacement tissues ex vivo for transplantation. One promising approach has been self-organizing organoids, which mimic developmental processes and yield multicellular, organ-specific tissues. However, a recognized roadblock to this approach is that many organoid cell types fail to acquire full maturity and function. Here, we comprehensively assess the vasculature in two distinct kidney organoid models as well as in explanted embryonic kidneys. Using a variety of methods, we show that while organoids can develop a wide range of kidney cell types, as previously shown, endothelial cells (ECs) initially arise but then rapidly regress over time in culture. Vasculature of cultured embryonic kidneys exhibit similar regression. By contrast, engraftment of kidney organoids under the kidney capsule results in the formation of a stable, perfused vasculature that integrates into the organoid. This work demonstrates that kidney organoids offer a promising model system to define the complexities of vascular-nephron interactions, but the establishment and maintenance of a vascular network present unique challenges when grown ex vivo.