Now showing items 1-20 of 15138

    • Predicting Medication Nonadherence in Older Adults With Difficult-to-Treat Depression in the IRL-GRey Randomized Controlled Trial

      Altmann, Helene M.; Kazan, Joseph; Gebara, Marie Anne; Blumberger, Daniel M.; Karp, Jordan F.; Lenze, Eric J.; Mulsant, Benoit H.; Reynolds, Charles F.; Stahl, Sarah T.; Department of Psychiatry, College of Medicine, University of Arizona (Elsevier BV, 2022-03)
      Objective: Nonadherence to antidepressants interferes with optimal treatment of late-life depression. This analysis examines clinical and treatment factors predicting medication nonadherence in difficult-to-treat late-life depression. Methods: Secondary analysis of data from a clinical trial of antidepressant pharmacotherapy for Major Depressive Disorder in 468 adults aged 60+ years. All participants received venlafaxine XR for 12 weeks. Nonremitters were randomized to augmentation with either aripiprazole or placebo for 12 additional weeks. Medication adherence was assessed 14 times over 24 weeks. The analyses examined sociodemographic, clinical, and treatment factors that may predict antidepressant nonadherence during early (weeks 1–6), late (weeks 7–12), and augmentation (weeks 13-–24) treatment. Results: Poor cognitive function and early response were predictive of early nonadherence. Poor cognitive function and prior nonadherence were predictive of late nonadherence. Living alone was associated with nonadherence both late and during augmentation treatment. Conclusion: Future studies should consider the role of early response and cognitive function to improve antidepressant adherence, particularly among older adults who live alone.
    • Implications of a “Null” Randomized Controlled Trial of Mindfulness and Compassion Interventions in Healthy Adults

      Kaplan, Deanna M.; Mehl, Matthias R.; Pace, Thaddeus W. W.; Negi, Lobsang Tenzin; Silva, Brendan Ozawa-de; Lavelle, Brooke D.; Sivilli, Teri; Williams, Allison; Comstock, Tom; Price, Bryan; et al. (Springer Science and Business Media LLC, 2022-04-21)
      Objectives: Extensive research suggests that short-term meditation interventions may hold therapeutic promise for a wide range of psychosocial outcomes. In response to calls to subject these interventions to more methodologically rigorous tests, a randomized controlled trial tested the effectiveness of a mindfulness meditation intervention and a compassion meditation intervention against an active control in a demographically diverse sample of medically and psychiatrically healthy adults. Methods: Two hundred and four participants completed a battery of questionnaires to assess psychological experience, participated in a laboratory stress test to measure their biological stress reactivity, and wore the Electronically Activated Recorder (EAR) to assess daily behaviors before and after an eight-week intervention (mindfulness meditation intervention, compassion meditation intervention, or health education discussion group). Results: Neither meditation intervention reliably impacted participants’ subjective psychological experience, biological stress reactivity, or objectively assessed daily behaviors. Furthermore, post hoc moderation analyses found that neither baseline distress nor intervention engagement significantly moderated effects. Conclusions: Results from this trial—which was methodologically rigorous and powered to detect all but small effects—were essentially null. These results are an important data point for the body of research about meditation interventions. Implications of these non-significant effects are discussed in the context of prior studies, and future directions for contemplative intervention research are recommended. Clinical Trial Registry: Registry Number: NCT01643369.
    • Less Than Fully Honest: Financial Deception in Emerging Adult Romantic Relationships

      Saxey, Matthew T.; LeBaron-Black, Ashley B.; Dew, Jeffrey P.; Curran, Melissa A.; University of Arizona (SAGE Publications, 2022-04-26)
      Emerging adults lack many basic financial capabilities. To avoid conflict that may come from these deficiencies, some emerging adults may financially deceive their romantic partner. However, little is known about financial deception in emerging adult romantic relationships. Through the lenses of two theoretical frameworks, we test whether financial deception intervenes the associations of couple financial communication, financial socialization, and similarity of financial values with romantic relationship flourishing in a sample of 1,950 U.S. emerging adults. Results indicate that couple financial communication, similarity of financial values, and financial socialization may contribute positively toward romantic relationship flourishing. However, financial socialization and financial deception may contribute negatively toward romantic relationship flourishing. Findings are discussed in light of the theoretical frameworks utilized, implications for clinicians and educators are identified, and directions for future research are presented. In summary, being less than fully honest about finances may have implications for emerging adults in romantic relationships.
    • Counteracting Dark Web Text-Based CAPTCHA with Generative Adversarial Learning for Proactive Cyber Threat Intelligence

      Zhang, Ning; Ebrahimi, Mohammadreza; Li, Weifeng; Chen, Hsinchun; University of Arizona (Association for Computing Machinery (ACM), 2022-06-30)
      Automated monitoring of dark web (DW) platforms on a large scale is the first step toward developing proactive Cyber Threat Intelligence (CTI). While there are efficient methods for collecting data from the surface web, large-scale dark web data collection is often hindered by anti-crawling measures. In particular, text-based CAPTCHA serves as the most prevalent and prohibiting type of these measures in the dark web. Text-based CAPTCHA identifies and blocks automated crawlers by forcing the user to enter a combination of hard-to-recognize alphanumeric characters. In the dark web, CAPTCHA images are meticulously designed with additional background noise and variable character length to prevent automated CAPTCHA breaking. Existing automated CAPTCHA breaking methods have difficulties in overcoming these dark web challenges. As such, solving dark web text-based CAPTCHA has been relying heavily on human involvement, which is labor-intensive and time-consuming. In this study, we propose a novel framework for automated breaking of dark web CAPTCHA to facilitate dark web data collection. This framework encompasses a novel generative method to recognize dark web text-based CAPTCHA with noisy background and variable character length. To eliminate the need for human involvement, the proposed framework utilizes Generative Adversarial Network (GAN) to counteract dark web background noise and leverages an enhanced character segmentation algorithm to handle CAPTCHA images with variable character length. Our proposed framework, DW-GAN, was systematically evaluated on multiple dark web CAPTCHA testbeds. DW-GAN significantly outperformed the state-of-the-art benchmark methods on all datasets, achieving over 94.4% success rate on a carefully collected real-world dark web dataset. We further conducted a case study on an emergent Dark Net Marketplace (DNM) to demonstrate that DW-GAN eliminated human involvement by automatically solving CAPTCHA challenges with no more than three attempts. Our research enables the CTI community to develop advanced, large-scale dark web monitoring. We make DW-GAN code available to the community as an open-source tool in GitHub.
    • Evaluation of individual and ensemble probabilistic forecasts of COVID-19 mortality in the United States

      Cramer, Estee Y; Ray, Evan L; Lopez, Velma K; Bracher, Johannes; Brennen, Andrea; Castro Rivadeneira, Alvaro J; Gerding, Aaron; Gneiting, Tilmann; House, Katie H; Huang, Yuxin; et al. (National Academy of Sciences, 2022-04-08)
      Significance: This paper compares the probabilistic accuracy of short-term forecasts of reported deaths due to COVID-19 during the first year and a half of the pandemic in the United States. Results show high variation in accuracy between and within stand-alone models and more consistent accuracy from an ensemble model that combined forecasts from all eligible models. This demonstrates that an ensemble model provided a reliable and comparatively accurate means of forecasting deaths during the COVID-19 pandemic that exceeded the performance of all of the models that contributed to it. This work strengthens the evidence base for synthesizing multiple models to support public-health action.
    • Impact of in-Station Medication Automated Dispensing Systems on Prehospital Pain Medication Administration

      Gaither, Joshua B.; Rice, Amber D.; Jado, Isrealia; Armstrong, Smita; Packard, Samuel E.; Clark, John; Draper, Scott; Duncan, Mike; Bradley, Brad; Spaite, Daniel W.; et al. (Informa UK Limited, 2022-04-15)
      Introduction: Medication automatic dispensing systems (ADS) have been implemented in many settings, including fire-based EMS stations. The aim of this study was to evaluate the impact of in-station ADSs on controlled substance administration rates and EMS response intervals. Methods: This study was a retrospective review of data from a single fire-based EMS agency. Medication administration rates and EMS response intervals were compared before ADS implementation (P1; 6/1/15 to 5/31/16) and after ADS implementation (P3; 6/1/17-5/31/19). Cases with missing data and during a one-year implementation period were excluded. Results: 4045 cases were identified in P1 and 8168 in P3. The odds of morphine or versed administration increased following ADS implementation: OR = 1.77 (95% CI: 1.53, 2.03) and OR = 1.53 (95%CI: 1.18, 2.00) respectively. There were statistically, but likely not operationally significant increases in median response interval and transport interval from P1 to P3 of 14 seconds, (p < 0.001) and 39 seconds (p < 0.001) respectively. Time at hospital for all calls decreased by more than 11 minutes for all transports, from a median of 34 minutes (IQR; 23.7, 45.5) to 22.7 minutes (IQR:18.5, 27.6) in P3, p < 0.001 and by 27.9 minutes for calls in which a controlled substance was given: P1 = 50.6 minutes (IQR: 34.6, 63.2), P3 = 22.7 minutes (IQR: 18.3, 27.4), p < 0.001. Conclusion: In this system, medication ADS implementation was associated with an increase in the rates of controlled substance administration and a decrease in the time units were at hospitals.
    • Sexual Minority Stressors and Intimate Partner Violence Among Same-Sex Couples: Commitment as a Resource

      Li, Xiaomin; Curran, Melissa A.; Butler, Emily; Mills-Koonce, W. Roger; Cao, Hongjian; Department of Family Studies and Human Development, University of Arizona (Springer Science and Business Media LLC, 2022-04-25)
      Accumulating evidence has been found for the associations from sexual minority stressors to intimate partner violence (IPV) among same-sex couples. Yet key gaps still exist, including the rare utilization of couple dyadic data, the understudied moderating and mediating mechanisms, and the few studies conducted during the transitional period of same-sex marriage legalization. To address these gaps, we used cross-sectional, dyadic data collected from 144 US same-sex couples during the 2014–2015 national campaign for the legalization of same-sex marriage. Guided by the systemic transactional model (STM), we examined associations from sexual minority stressors (including both internalized homophobia and discrimination) to same-sex IPV and tested whether commitment moderated or mediated these associations. Overall, we found evidence supporting the STM: (1) High internalized homophobia and discrimination were related to high prevalence and/or frequency of IPV perpetration; (2) high commitment attenuated positive associations between high discrimination and high prevalence and/or frequency of IPV perpetration; and (3) high internalized homophobia was related to low commitment, which in turn was related to high prevalence and/or frequency of IPV perpetration. Collectively, our study identified commitment as both a moderator and mediator in associations from sexual minority stressors to same-sex IPV. Further, the roles of commitment (i.e., moderator or mediator) depend on whether the focal sexual minority stressors are distal and more intermittent (i.e., heterosexist discrimination) or proximal and more constant (i.e., internalized homophobia).
    • Control, cost, and confidence: Perseverance and procrastination in the face of failure

      Deimen, Inga; Wirtz, Julia; University of Arizona, Eller College of Management, Department of Economics (Elsevier BV, 2022-07)
      We study effort provision and the development of the belief that effort matters over time: a student is uncertain whether she has control over success through her effort or whether success is determined by her innate ability, which she also does not know. In each period, what she can learn about her control and her ability depends on the level of effort she exerts. The student's optimal effort policy in this two-dimensional bandit problem takes the form of a linear belief cutoff rule and typically features repeated switching of the effort level. Moreover, we define perseverance and procrastination as indices for the student's behavior over time and analyze how they are affected by control, cost, and confidence. Finally, we relate our results to findings in educational psychology and discuss policies to foster perseverance and to lower procrastination.
    • Examining the perspectives of adult working learners and key stakeholders using critical race theory

      Jacobs, Gloria E.; Castek, Jill; Harris, Kathy; Vanek, Jen; The University of Arizona College of Education (Emerald, 2022-03-31)
      Purpose: This article reports on a critical race theory (CRT) analysis of the perspectives of providers of employer-supported educational opportunities and adult learners, who identified as Black, indigenous or as a person of color, and were employed in service industries. Design/methodology/approach: A review of the literature was used to shape an initial interview protocol. Data were collected from working learners in retail, hospitality, restaurants and healthcare industries. An “a priori” coding scheme that drew from CRT was applied to transcripts during analysis. Findings: Analysis revealed that working learners' skills, experiential knowledge, learning mindset, language flexibility and knowledge gained from previous learning experiences were not consistently acknowledged by employers. CRT analysis illustrated that endemic racism exists within educational opportunities and in workplace learning. Originality/value: CRT has not been widely used to examine adult education practice, especially for workforce development and employer-based education programs. This research expands the use of CRT in adult education and encourages critical conversations around equity in learning opportunities offered by employers. CRT informed data analysis uncovered barriers to equitable learning opportunities and workplace learning. A discussion of inequities in work-based learning illustrates there is insufficient awareness of implicit bias, which points to the need for initiatives focused on social justice.
    • Pluto near the edge of chaos

      Malhotra, Renu; Ito, Takashi; Lunar and Planetary Laboratory, University of Arizona (National Academy of Sciences, 2022-03-31)
      Significance: The dwarf planet, Pluto, has stirred the imagination of the public and of planetary scientists due to its many unusual properties. Among these properties is its Neptune-crossing orbit whose stability is owed to an orbital resonance with Neptune. Less well understood is the role of the other planets. We demonstrate that the orbital architecture of the giant planets lies within a narrow niche in which Pluto-like orbits are practically stable on gigayear timescales, whereas nearby are strongly chaotic orbits. Pluto is witness to the dynamical history of the solar system; quantifying its proximity to strong chaos and dynamical instability can enable quantitative constraints on its own dynamical history as well as that of the solar system.
    • The relationship of vancomycin 24-hour AUC and trough concentration

      Nix, David E; Davis, Lisa E; Matthias, Kathryn R; Department Of Pharmacy Practice And Science, Department Of Medicine, University Of Arizona (Oxford University Press (OUP), 2021-11-27)
      Purpose: Prior to the 2020 release of a joint consensus guideline on monitoring of vancomycin therapy for serious methicillin-resistant Staphylococcus aureus (MRSA) infections, clinicians had escalated vancomycin doses for 2 decades while targeting trough concentrations of 15 to 20 μg/mL, leading to an increased frequency of nephrotoxicity. For MRSA infections, the 2020 guideline recommends adjusting doses to achieve a 24-hour area under the concentration-time curve (AUC) of 400 to 600 μg · h/mL; however, monitoring of trough concentrations has been entrenched for 3 decades. Calculating dose regimens based on AUC will require obtaining an increased number of vancomycin serum concentrations and, possibly, advanced software. The aim of this investigation was to determine the relationship between AUC and trough concentration and the influence of dosing regimen on goal achievement. Methods: The relationship between trough concentration and AUC was explored through derivation of an equation based on a 1-compartment model and simulations. Results: 24-hour AUC is related to dosing interval divided by half-life in a nonlinear fashion. The target trough concentration can be individualized to achieve a desired AUC range, and limiting use of large doses (>15-20 mg/kg) can protect against excessive 24-hour AUC with trough-only monitoring. Conclusion: After initially determining pharmacokinetic parameters, subsequent monitoring of AUC can be accomplished using trough concentrations only. Trough concentration may be used as a surrogate for AUC, although the acceptable target trough concentration will vary depending on dosing interval and elimination rate constant. This work included development of an AUC-trough equation to establish a patient-specific target for steady-state trough concentration.
    • Is the gender difference in competitive behavior history dependent?

      Rhee, Elaine; Noussair, Charles N.; University of Arizona, Department of Economics (Elsevier BV, 2022-06)
      This study tests whether men and women differ in their willingness to challenge a competitor in response to a prior transgression. A laboratory experiment is conducted, in which a player can choose to behave unfairly toward another. The other player may then challenge the first to a contest. We investigate the extent to which previous interactions can explain individual differences in tournament initiation decisions. The results show that men, but not women, tend to challenge a competitor more when the prior outcome is unfair and the unfairness occurred through the competitor's intentional choice. In contrast, unfair outcomes that occur by chance do not influence the decision to challenge others.
    • Screening for cognitive symptoms among cancer patients during chemotherapy: Sensitivity and specificity of a single item self-report cognitive change score

      Fardell, Joanna E; Bray, Victoria; Bell, Melanie L; Rabe, Brooke; Dhillon, Haryana; Vardy, Janette L; Department of Epidemiology and Biostatistics, Mel and Enid Zuckerman College of Public Health, University of Arizona (John Wiley and Sons Ltd, 2022-03-23)
      Objectives: Cognitive symptoms are commonly reported among cancer patients and survivors, yet guidance on when self-reported cognitive symptoms warrant follow-up is lacking. We sought to establish cut-off scores for identifying patients with perceived low cognitive functioning on widely used self-report measures of cognition and a novel single item Cognitive Change Score. Methods: Adult patients diagnosed with invasive cancer who had completed at least one cycle of chemotherapy completed a questionnaire containing the EORTC-Cognitive Function (CF) subscale, Functional Assessment of Cancer Therapy-Cognitive Function (FACT-COG) Perceived Cognitive Impairment (PCI) and our Cognitive Change Score (CCS). We used receiver operating characteristic analyses to establish the discriminative ability of these measures against the Patient's Assessment of Own Functioning Inventory (PAOFI) as our reference standard. We chose cut-off scores on each measure that maximised both sensitivity and specificity for identifying patients with self-reported low CF. Results: We recruited 294 participants (55.8% women, mean age 56.6 years) with mixed cancer diagnoses (25.5 months since diagnosis). On the CCS, 77.6% reported some cognitive change since starting chemotherapy. On the PAOFI 36% had low CF. The following cut-off scores identified cases of low CF: ≥28.5 on the CCS (75.5% sensitivity, 67.6% specificity); ≤75.0 on the European Organisation for Research and Treatment of Cancer, QLQ-C30 Cognitive Functioning scale (90.9% sensitivity, 57.1% specificity); ≤55.1 on the FACT-COG PCI-18 (84.8% sensitivity, 76.2% specificity), and ≤59.5 on the FACT-COG PCI-20 (78.8% sensitivity, 84.1% specificity). Conclusions: We found a single item question asking about cognitive change has acceptable discrimination between patients with self-reported normal and low CF when compared to other more comprehensive self-report measures of cognitive symptoms. Further validation work is required.
    • Russian thistle (Salsola spp.) control in California rangelands over five years

      Rao, Devii R.; Hovanes, Katherine; Smith, Richard; Davy, Josh; Gornish, Elise S.; University of Arizona, School of Natural Resources and the Environment (Cambridge University Press (CUP), 2022-03-21)
      Russian thistle, also known as tumbleweed (Salsola spp.), is a problematic invasive plant found on natural and working landscapes. On a California rangeland, we tested the singular and interactive treatments of grazing, herbicide and seeding to determine how these approaches might influence Salsola cover across a five year experiment. Total Salsola cover declined by 3% annually during the study. A single spring treatment of chlorsulfuron + 2,4-D followed by glyphosate applied in the fall just prior to seeding, and then 2,4-D the following spring, significantly reduced Salsola cover compared to the untreated control. Seeded forage species cover increased over time and was significantly higher than seeded native species cover five years after seeding. However, the seeding treatment had no effect on Salsola cover. Although grazing did not reduce Salsola cover, due to the beneficial effects of grazing on reducing other non-native species, this study supports the use of an integrated approach of herbicide application, grazing and seeding to achieve management goals on an arid working landscape.
    • Synthesis of alamandine glycoside analogs as new drug candidates to antagonize the MrgD receptor for pain relief

      Alabsi, Wafaa; Jaynes, Timothy; Alqahtani, Tariq; Szabo, Lajos; Sun, Daekyu; Vanderah, Todd W.; Mansour, Heidi M.; Polt, Robin; Department of Chemistry & Biochemistry, The University of Arizona; College of Pharmacy, Skaggs Pharmaceutical Sciences Center, The University of Arizona; et al. (Springer Science and Business Media LLC, 2022-04-08)
      Two series of putatively brain-penetrant alamandine glycosides have been prepared for screening against the MrgD receptor. The first series retains the initial six residues of the alamandine sequence (ARVYIHP) as the “peptide message,” replacing the C-terminal proline (P) with several serine (S) glycosides at the C-terminus to produce “glycoside addresses”. In the second series, steric bulk was altered to modify the “peptide message”– the N-terminal alanine (A) residue was substituted with glycine (G); D-alanine (a); nor-valine (norV); D-nor-valine (D-norV); valine (V); and D-nor-valine (v), keeping the C-terminal serine-beta-D-glucoside (S-Glc) “glycoside address” constant. All the peptides and glycopeptides were synthesized as their C-terminal amides. The purity of native alamandine and its eleven selected derivatives were each confirmed using analytical HPLC. Also, the molecular weight and chemical composition were confirmed using mass spectroscopy. The MrgD receptor expression was evaluated in rationally chosen human cell lines, A549 and HEK 293. Both cell lines showed the presence of the MrgD receptor around 35 kDa, as confirmed by western blot analysis. The effect of varying concentrations of some alamandine derivatives on cell viability was evaluated on HEK 293 and A549 cell lines.
    • Climate impact or policy choice? The spatiotemporality of thermoregulation and border crosser mortality in southern Arizona

      Chambers, Samuel N.; Boyce, Geoff; Martínez, Daniel E.; Department of Epidemiology and Biostatistics, Zuckerman College of Public Health, The University of Arizona; School of Sociology, The University of Arizona (Wiley, 2022-04-14)
      US public officials frequently argue that high temperatures are responsible for increasing mortality of undocumented border crossers (UBCs) in southern Arizona. In this article, we suggest that these kinds of assertions are not only empirically misleading, they also serve to naturalise UBC deaths in the region by helping to obscure their structural causes. Indeed, although heat exposure is a primary cause of death in the region, prior studies have also shown that migration patterns have shifted toward more remote and rugged terrain, characterised by higher elevations and greater shade cover. Using physiological modelling and a spatiotemporal forensic analysis, we assess whether the distribution of recovered human remains has shifted toward locations characterised by environments where the human body is more or less capable of regulating core temperature, and thus succumbing to heat stress. We find that the distribution of recovered UBC remains has consistently trended toward locations where the potential for heat stress is lower, rather than higher. This demonstrates that UBC mortality is not principally a function of ambient or regional temperature, but rather is a result of specific policy decisions that lead to cumulative stress and prolonged exposure due to factors like difficulty and distance of travel. To contextualise these findings, we discuss the evolution of the US Border Patrol's policy of Prevention Through Deterrence, and apply the concepts of structural and cultural violence to theorize its consistently deadly outcomes. The information, practices and views in this article are those of the author(s) and do not necessarily reflect the opinion of the Royal Geographical Society (with IBG).
    • The Sounds of Memory: Extending the Age–Prospective Memory Paradox to Everyday Behavior and Conversations

      Haas, Maximilian; Mehl, Matthias R; Ballhausen, Nicola; Zuber, Sascha; Kliegel, Matthias; Hering, Alexandra; Department of Psychology, University of Arizona (Oxford University Press (OUP), 2022-01-29)
      Objectives: Around the turn of the millennium, the "age-prospective memory (PM) paradox" challenged the classical assumption that older adults necessarily evidence a marked decline in PM functioning. As previous investigations highlighted ecological validity to be a potential explanation, the present study sought to extend established approaches by using novel real-world assessment technologies to examine PM unobtrusively in everyday-life conversations. Method: Next to laboratory PM tasks, real-life PM performance of 53 younger adults (19-32 years) and 38 older adults (60-81 years) was assessed from three sources: Over 9 days, participants completed an experimenter-given naturalistic task, a diary-based approach assessing self-assigned intentions, as well as an ambulatory assessment with the Electronically Activated Recorder (EAR), a device that unobtrusively samples ambient sounds to detect spontaneous speech production related to (lapses in) everyday PM. Results: Older adults showed lower performance in laboratory PM only for the time-based task and performed either equally well as or even better than younger adults in everyday PM. With regard to PM performance as captured in real-life ambient audio data, younger adults talked more frequently about PM than older adults, but no significant difference between younger and older adults was found for speech related to PM errors. Discussion: Findings confirmed older adults' preserved PM performance in everyday life across different indicators with increasing ecological validity. Furthermore, as a novel method to assess conversational PM in everyday life, the EAR opens new insights about the awareness of PM lapses and the communication of intentions in real life.
    • Plio-Pleistocene environmental variability in Africa and its implications for mammalian evolution

      Cohen, Andrew S.; Du, Andrew; Rowan, John; Yost, Chad L.; Billingsley, Anne L.; Campisano, Christopher J.; Brown, Erik T.; Deino, Alan L.; Feibel, Craig S.; Grant, Katharine; et al. (Proceedings of the National Academy of Sciences, 2022-04-11)
      Significance: We have developed an Africa-wide synthesis of paleoenvironmental variability over the Plio-Pleistocene. We show that there is strong evidence for orbital forcing of variability during this time that is superimposed on a longer trend of increasing environmental variability, supporting a combination of both low- and high-latitude drivers of variability. We combine these results with robust estimates of mammalian speciation and extinction rates and find that variability is not significantly correlated with these rates. These findings do not currently support a link between environmental variability and turnover and thus fail to corroborate predictions derived from the variability selection hypothesis.
    • Coordinated chemical and microstructural analyses of presolar silicate grains from AGB/RGB stars and supernovae in the CO3.0 chondrite Dominion Range 08006

      Seifert, Laura B.; Haenecour, Pierre; Zega, Thomas J.; Lunar and Planetary Laboratory, University of Arizona; Department of Materials Science and Engineering, University of Arizona (Wiley, 2022-04-11)
      We report the structural and chemical analyses of six presolar silicate grains identified in situ in the CO3.0 carbonaceous chondrite Dominion Range (DOM) 08006. Two of the grains have O-isotopic compositions consistent with origins in the circumstellar envelopes of low-mass (&lt;2M☉) asymptotic giant branch (AGB)/red giant branch (RGB) stars, although without Mg-isotopic data, origins in supernovae (SNe) cannot be ruled out. The other four grains have O-isotopic compositions consistent with origins in the ejecta of type-II SNe. Transmission electron microscopy analyses reveal that all grains are crystalline (single crystal or polycrystalline) and have varied compositions. The analyzed AGB/RGB grains include an Fe-rich crystalline olivine with an Fe-sulfide inclusion and a chemically zoned olivine grain that also contains an Fe-oxide rim. The grains derived from SNe include two polycrystalline assemblages with structures that overlap with both olivine and pyroxene, an assemblage composed of both a single crystal of forsterite and polycrystalline forsterite, and an orthopyroxene grain with an embedded Fe-sulfide crystal. The thermodynamic origins of both AGB/RGB and SN grains are also diverse. The structure and compositions of two grains are consistent with equilibrium thermodynamic predictions of condensation, whereas four are not, suggesting formation through nonequilibrium or multistep processes. Our observations of presolar silicate grains suggest that the circumstellar envelopes of AGB/RGB stars and the ejecta of SNe can produce grains with comparable structures and compositions.
    • The Adapa Tablets and the Tuxtla Glyphs: Coevolution Between Human and Nonhuman Animals

      Figueredo, Aurelio José; Steklis, Netzin Gerald; Peñaherrera-Aguirre, Mateo; Fernandes, Heitor Barcellos Ferreira; Cabeza De Baca, Tomás; Salmon, Catherine; Hernández-Chaves, María Gabriela; Araya, Siu Fong Acón; Pérez-Ramos, Marisol; Frías-Armenta, Martha; et al. (Springer Science and Business Media LLC, 2022-04-13)
      The purpose of this study was to examine how attitudes toward different nonhuman animal species (including emotional empathy, cognitive empathy, and harm avoidance) are shaped by the coevolutionary histories between the ancestors of contemporary humans and these different nonhuman animal species. We compared the explanatory power of alternative categorization frameworks for classifying attitudes toward animals across several cross-cultural samples (Arizona, California, Costa Rica, Spain, and Mexico). Analytical Approach 1 directly compared two alternative frameworks. Adapa categories were generated as purely functional ones based upon the ecological niches occupied by each species within the biotic community generated by human–nonhuman animal relations, and Tuxtla categories were generated as cognitive ones based upon the degrees of consciousness commonly ascribed to the constituent species. Analytical Approach 2 tested the alternative hypothesis that both categories were part of a general scheme organized into three superordinate categories reflecting concentric circles around our own, consistent with fitness interdependence theory. Results supported this alternative hypothesis. The concentric circles model (Kith & Kin Animals, Domesticated Animals, and Wild Animals) better explained empathy and harm avoidance scores, suggesting that attitudes toward specific animal species are partly shaped by which circles they fall into, the product of the coevolutionary relationship shared between them and humans.