• Diffusion anisotropy of Ti in zircon and implications for Ti-in-zircon thermometry

      Bloch, E.M.; Jollands, M.C.; Tollan, P.; Plane, F.; Bouvier, A.-S.; Hervig, R.; Berry, A.J.; Zaubitzer, C.; Escrig, S.; Müntener, O.; et al. (Elsevier BV, 2022-01)
      Ti-in-zircon thermometry has become a widely used tool to determine zircon crystallization temperatures, in part due to reports of extremely sluggish Ti diffusion perpendicular to the crystallographic c-axis in this mineral. We have conducted Ti-in-zircon diffusion experiments, focusing on diffusion parallel to the c-axis, at 1 atm pressure between 1100 and 1540 °C, with oxygen fugacities equivalent to air and the Ni-NiO buffer. There is no resolvable dependence of Ti diffusion in zircon upon silica or zirconia activity, or upon oxygen fugacity. The diffusion coefficient of Ti in zircon is found to be a weak function of its own concentration, spanning less than 0.5 log units across any profile induced below 1300 °C. Ti diffusion in zircon, parallel to the c-axis at 1 atm pressure, is well described using: [Formula presented] where R is the gas constant in J/(mol⋅K). In conjunction with diffusion coefficients for Ti in zircon perpendicular to the c-axis reported by Cherniak and Watson (2007), strong diffusion anisotropy for Ti in zircon is observed. Diffusion parallel to the c-axis is ∼4-5 orders of magnitude faster than diffusion perpendicular to the c-axis within the experimentally constrained temperature range shared between these two studies (1540-1350 °C). This difference increases if the data are extrapolated to lower temperatures and reaches ∼7.5-11 orders of magnitude between 950-600 °C, a typical range for zircon crystallization. Diffusion of Ti in natural zircons will predominantly occur parallel to the c-axis, and the Ti-in-zircon thermometer appears susceptible to diffusive modification under some crustal conditions. Temperatures calculated using this system should therefore be evaluated on a case-by-case basis, particularly when considering high-T, slowly cooled, reheated and/or small zircons.
    • Dogs re-engage human partners when joint social play is interrupted: a behavioural signature of shared intentionality?

      Horschler, Daniel J.; Bray, Emily E.; Gnanadesikan, Gitanjali E.; Byrne, Molly; Levy, Kerinne M.; Kennedy, Brenda S.; MacLean, Evan L.; School of Anthropology, University of Arizona; Cognitive Science Program, University of Arizona; Department of Psychology, University of Arizona; et al. (Elsevier BV, 2022-01)
      Hypotheses regarding the evolution of uniquely human social cognition often emphasize not only mental state representation, but also mental state sharing. Mental state sharing is evident in instances of joint intentionality – mutual understanding between individuals of each other's simultaneous and interdependent commitment to a shared activity or goal. Comparative studies supporting the human uniqueness of joint intentionality show that, as compared to human children, chimpanzees, Pan troglodytes, who engage with humans as cooperative partners do not altruistically help others achieve their goals across the same range of contexts, do not attempt to re-engage cooperative partners in problem-solving or social games at the same rate and do not show spontaneous role reversal. Although recent work supports the possibility that bonobos, Pan paniscus, may re-engage conspecific partners after interrupted social grooming, the extent to which other animals show similar behaviour across more diverse contexts remains largely unexplored. Domestic dogs', Canis familiaris, propensity to interact with humans in cooperative contexts makes them a potentially promising comparative model of prosocial mental state sharing. Here, we investigated a behavioural signature of joint intentionality during social play between humans and dogs (N = 82). Our results present the first experimental evidence of re-engagement behaviour in dogs, as dogs preferentially attempted to reinitiate an interrupted social game with their previous partner relative to a passive bystander. These findings suggest that dogs exhibit a key marker of joint intentionality and open the door for future research on the cognitive mechanisms supporting this behaviour.
    • Physachenolide C induces complete regression of established murine melanoma tumors via apoptosis and cell cycle arrest

      Adams, A.C.; Macy, A.M.; Kang, P.; Castro-Ochoa, K.F.; Wijeratne, E.M.K.; Xu, Y.-M.; Liu, M.X.; Charos, A.; Bosenberg, M.W.; Gunatilaka, A.A.L.; et al. (Neoplasia Press, Inc., 2022)
      Melanoma is an aggressive skin cancer that metastasizes to other organs. While immune checkpoint blockade with anti-PD-1 has transformed the treatment of advanced melanoma, many melanoma patients fail to respond to anti-PD-1 therapy or develop acquired resistance. Thus, effective treatment of melanoma still represents an unmet clinical need. Our prior studies support the anti-cancer activity of the 17β-hydroxywithanolide class of natural products, including physachenolide C (PCC). As single agents, PCC and its semi-synthetic analog demonstrated direct cytotoxicity in a panel of murine melanoma cell lines, which share common driver mutations with human melanoma; the IC50 values ranged from 0.19–1.8 µM. PCC treatment induced apoptosis of tumor cells both in vitro and in vivo. In vivo treatment with PCC alone caused the complete regression of established melanoma tumors in all mice, with a durable response in 33% of mice after discontinuation of treatment. T cell-mediated immunity did not contribute to the therapeutic efficacy of PCC or prevent tumor recurrence in YUMM2.1 melanoma model. In addition to apoptosis, PCC treatment induced G0-G1 cell cycle arrest of melanoma cells, which upon removal of PCC, re-entered the cell cycle. PCC-induced cycle cell arrest likely contributed to the in vivo tumor recurrence in a portion of mice after discontinuation of treatment. Thus, 17β-hydroxywithanolides have the potential to improve the therapeutic outcome for patients with advanced melanoma. © 2021
    • Kinetic Alfvénic cnoidal waves in Saturnian magnetospheric plasmas

      Singh, Manpreet; Singh, Kuldeep; Saini, N. S.; Department of Planetary Sciences-Lunar and Planetary Laboratory, University of Arizona (Informa UK, 2021-12-28)
      The characteristics of kinetic Alfvénic cnoidal waves (KACWs) in Saturn's magnetosphere plasma composed of two temperature superthermal electrons and inertial ions are presented. The Korteweg–de Vries (KdV) equation and its cnoidal wave solution are derived by adopting reductive perturbation technique. Only positive potential kinetic Alfvénic cnoidal and solitary waves are evolved in Saturnian magnetospheric plasma. The influence of superthermality of cold electrons, concentration of hot electrons, plasma beta and angle of propagation of the wave with respect to the magnetic field has been analyzed on the characteristics of KACWs. The findings of this investigation may shed the light on the possible existence of KACWs and acceleration as well as energy transportation in space plasmas especially in Saturn's magnetosphere.
    • Pattern-based downscaling of snowpack variability in the western United States

      Gauthier, Nicolas; Anchukaitis, Kevin J.; Coulthard, Bethany; School of Geography, Development and Environment, University of Arizona; Laboratory of Tree-Ring Research, University of Arizona (Springer Science and Business Media LLC, 2021-12-27)
      The decline in snowpack across the western United States is one of the most pressing threats posed by climate change to regional economies and livelihoods. Earth system models are important tools for exploring past and future snowpack variability, yet their coarse spatial resolutions distort local topography and bias spatial patterns of accumulation and ablation. Here, we explore pattern-based statistical downscaling for spatially-continuous interannual snowpack estimates. We find that a few leading patterns capture the majority of snowpack variability across the western US in observations, reanalyses, and free-running simulations. Pattern-based downscaling methods yield accurate, high resolution maps that correct mean and variance biases in domain-wide simulated snowpack. Methods that use large-scale patterns as both predictors and predictands perform better than those that do not and all are superior to an interpolation-based “delta change” approach. These findings suggest that pattern-based methods are appropriate for downscaling interannual snowpack variability and that using physically meaningful large-scale patterns is more important than the details of any particular downscaling method.
    • Both source‐ and recipient‐range phylogenetic community structure can predict the outcome of avian introductions

      Maitner, Brian S.; Park, Daniel S.; Enquist, Brian J.; Dlugosch, Katrina M.; Department of Ecology & Evolutionary Biology, University of Arizona (Wiley, 2021-12-24)
      Competing phylogenetic models have been proposed to explain the success of species introduced to other communities. Here, we present a study predicting the establishment success of birds introduced to Florida, Hawaii and New Zealand using several alternative models, considering species' phylogenetic relatedness to source- and recipient-range taxa, propagule pressure and traits. We find consistent support for the predictive ability of source-region phylogenetic structure. However, we find that the effects of recipient-region phylogenetic structure vary in sign and magnitude depending on inclusion of source-region phylogenetic structure, delineation of the recipient species pool and the use of phylogenetic correction in the models. We argue that tests of alternative phylogenetic hypotheses including both source and recipient community phylogenetic structure, as well as important covariates such as propagule pressure, are likely to be critical for identifying general phylogenetic patterns in introduction success, predicting future invasions and for stimulating further exploration of the underlying mechanisms of invasibility.
    • Socially distributed leadership in elementary schools: teacher and staff leadership practice in Denmark and the USA

      Modeste, Marsha E.; Nguyen, Chi; Nafziger, Rhoda Nanre; Hermansen, Jonathan; University of Arizona (Emerald, 2021-12-24)
      Purpose: The purpose of this study is to examine the nature of socially distributed leadership in Denmark and the USA, specifically teacher and staff leadership practices distributed in schools. Design/methodology/approach: This study used a confirmatory factor analysis and a second-order factor analysis to examine elementary USA and 0–9 Danish school educators’ responses to the Comprehensive Assessment of Leadership for Learning. Findings: Findings from this analysis of leadership practice demonstrate (1) different approaches to teacher and staff leadership in Denmark and the USA; (2) the importance of a collaborative approach to developing and maintaining professional learning communities in schools in both contexts; and (3) different patterns of leadership practice that broadly reflect the local structure and approach to school leadership while responding to external policy demands. Originality/value: Drawing on the globalization scholarship, which acknowledges the connection between global policy development and local spaces of implementation, this comparative international study allowed us to examine how policy ideas are parlayed into practice through the use of a shared assessment of leadership practice. The results of this study suggest that while the work of teacher and staff leadership is important and something that educators in Denmark and the USA are engaging in to advance the overall instructional mission of their schools, the approaches taken in each context are different and reflect a local-level negotiation between contextual cultural norms and policy expectations.
    • Resolving Atomic‐Scale Interactions in Nonfullerene Acceptor Organic Solar Cells with Solid‐State NMR Spectroscopy, Crystallographic Modelling, and Molecular Dynamics Simulations

      R. Luginbuhl, Benjamin; Raval, Parth; Pawlak, Tomasz; Du, Zhifang; Wang, Tonghui; Kupgan, Grit; Schopp, Nora; Chae, Sangmin; Yoon, Sangcheol; Yi, Ahra; et al. (Wiley, 2021-12-22)
      Fused-ring core nonfullerene acceptors (NFAs), designated “Y-series,” have enabled high-performance organic solar cells (OSCs) achieving over 18% power conversion efficiency (PCE). Since the introduction of these NFAs, much effort has been expended to understand the reasons for their exceptional performance. While several studies have identified key optoelectronic properties that govern high PCEs, little is known about the molecular level origins of large variations in performance, spanning from 5% to 18% PCE, for example, in the case of PM6:Y6 OSCs. Here, a combined solid-state NMR, crystallography, and molecular modeling approach to elucidate the atomic-scale interactions in Y6 crystals, thin films, and PM6:Y6 bulk heterojunction (BHJ) blends is introduced. It is shown that the Y6 morphologies in BHJ blends are not governed by the morphology in neat films or single crystals. Notably, PM6:Y6 blends processed from different solvents self-assemble into different structures and morphologies, whereby the relative orientations of the sidechains and end groups of the Y6 molecules to their fused-ring cores play a crucial role in determining the resulting morphology and overall performance of the solar cells. The molecular-level understanding of BHJs enabled by this approach will guide the engineering of next-generation NFAs for stable and efficient OSCs.
    • Precipitation temporal repackaging into fewer, larger storms delayed seasonal timing of peak photosynthesis in a semi‐arid grassland

      Zhang, Fangyue; Biederman, Joel A.; Pierce, Nathan A.; Potts, Daniel L.; Devine, Charles John; Hao, Yanbin; Smith, William K.; School of Natural Resources and the Environment, University of Arizona (Wiley, 2021-12-21)
      Against a backdrop of rising temperature, large portions of the western United States are experiencing fewer, larger and less frequent precipitation events. How such temporal ‘repackaging’ of precipitation alters the magnitude and timing of seasonal maximum gross primary productivity (GPPmax) remains unknown. Addressing this knowledge gap is critical, since changes to GPPmax magnitude and timing can impact a range of ecosystem services and management decisions. Here we used a field-based precipitation manipulation experiment in a semi-arid mixed annual/perennial bunchgrass ecosystem with mean annual precipitation ~384 mm to investigate how temporal repackaging of a fixed total seasonal precipitation amount impacts seasonal GPPmax and its timing. We found that temporal repackaging of precipitation profoundly influenced the seasonal timing of GPPmax. Many/small precipitation events advanced the seasonal timing of GPPmax by ~13 days in comparison with climatic normal precipitation. Conversely, few/large events led to deeper soil water infiltration, which delayed the timing of GPPmax by up to 16 days in comparison with climatic normal precipitation, and altered end-of-season community composition by increasing the diversity of shallow-rooted annual plants. While GPPmax magnitude did not differ across precipitation treatments, it was positively correlated with the abundance and biomass of deeper-rooted perennial bunchgrasses. The sensitivity of plant growth, biomass accumulation and plant life histories to the timing and magnitude of precipitation events and the resulting temporal patterns of soil moisture regulated ecosystem responses to altered precipitation patterns. Our results highlight the sensitivity of semi-arid grassland ecosystem to the temporal repackaging of precipitation. We find that already-observed and model-forecasted shifts toward few/large precipitation events could drive significant delays in the timing of peak productivity for this ecosystem. Adaptive land management frameworks should consider these findings since shifts in peak ecosystem productivity would have major implications for multiple land user communities. Additional research is needed to better understand the role of climate, community composition and soil properties in mediating variability in the seasonal timing of maximum ecosystem productivity. A free Plain Language Summary can be found within the Supporting Information of this article.
    • Shared musical activity and perceptions of relationship commitment

      Harwood, Jake; Wallace, Sandi D; Department of Communication, The University of Arizona (SAGE Publications, 2021-12-21)
      Sharing music with another person involves the potential for profound emotional connection, rhythmic synchronization and coordination, and the expression of shared social and political values (among other things). We explore whether experiences of shared musical activity are associated with perceptions of communication and positive outcomes in friendships and romantic relationships, using reports from one member of the dyad. Reports of musical activities in the relationship were associated with higher levels of commitment to the relationship, with those effects mediated by perceptions of interpersonal coordination and positive communication. Surprisingly, structured musical activities (e.g., actively playing music together) were associated with lower levels of commitment, both directly and via interpersonal coordination, positive communication, and shared social values. All findings persist when controlling for other forms of shared relationship activities, thus demonstrating effects that are unique to shared musical engagement. The findings are discussed in a framework of music’s potential relational power—the Shared Musical Activities in Relationships (SMAR) model.
    • The second engraver of the library of congress mystery map

      Terry Bahill, A.; Systems and Industrial Engineering, University of Arizona (Informa UK Limited, 2021-12-20)
      The Library of Congress has a map that they credit to Gerald Mercator and André Thevet with a creation date of 1569. Visual inspection suggests that this map had two engravers. One was the original cartographer who engraved the whole map placing toponyms where appropriate. Later, the second engraver added about five dozen toponyms. This paper identifies these two engravers and suggests the dates in which they did their work. © 2021 International Cartographic Association.
    • The Scope of Rape Victimization and Perpetration Among National Samples of College Students Across 30 years

      Koss, Mary P.; Swartout, Kevin M.; Lopez, Elise C.; Lamade, Raina V.; Anderson, Elizabeth J.; Brennan, Carolyn L.; Prentky, Robert A.; Department of Health Promotion Sciences, Mel and Enid Zuckerman College of Public Health, University of Arizona (SAGE Publications, 2021-12-15)
      Research Questions: Rape prevention practice and policy have roots in data from 1985. This study uses 2015 national data to project recent prevalence, assesses whether rates now differ from those of 30 years ago, and disaggregates 2015 prevalence into rape of alcohol incapacitated victims, rapes combining both alcohol and physical tactics, and violent rape. Methods: Cross-sectional analyses were conducted comparing two national samples. The first was collected in 1984-85 (Koss, Gidycz, & Wisniewski, 1987); the second was collected 30 years later in 2014-2015. Both surveys used in-person administration and measurement by the most current version at the time of the Sexual Experiences Survey (SES). Prevalence rates were compared using Bayesian binomial tests. Results: In 2015, 33.4% (1 in 3) of women reported experiencing rape or attempted rape and 12.7% of men reported perpetration (1 in 8). Using Jeffreys' label for effect size of the Bayes binomial (1961), both results are “decisively” greater than expected given the 1985 benchmarks of 27.9% for victimization and 7.7% for perpetration. Victimization when incapacitated characterized approximately 75% of incidents in 2015 up from 50% in 1985. Cautions apply as cross-sectional data does not establish causality and the recent data set involved the revised SES. Conclusions: Across 30 years, neither containment nor reduction of rape was demonstrated and the increasingly prominent association with alcohol was apparent. Among the men who disclosed raping, 9 of 10 incidents were alcohol-involved. Prevention focus might profitably be directed to constraining alcohol environments and policies that facilitate rape of incapacitated persons and on misconduct responses that are proportional to the harm caused to rape victims, thereby raising the perceived risks of perpetration.
    • Long‐term single‐column model intercomparison of diurnal cycle of precipitation over midlatitude and tropical land

      Tang, Shuaiqi; Xie, Shaocheng; Guo, Zhun; Hong, Song‐You; Khouider, Boualem; Klocke, Daniel; Köhler, Martin; Koo, Myung‐Seo; Krishna, Phani Murali; Larson, Vincent E.; et al. (Wiley, 2021-12-15)
      General Circulation Models (GCMs) have for decades exhibited difficulties in modelling the diurnal cycle of precipitation (DCP). This issue can be related to inappropriate representation of the processes controlling sub-diurnal phenomena like convection. In this study, 11 single-column versions of GCMs are used to investigate the interactions between convection and environmental conditions, processes that control nocturnal convections, and the transition from shallow to deep convection on a diurnal time-scale. Long-term simulations are performed over two continental land sites: the Southern Great Plains (SGP) in the USA for 12 summer months from 2004 to 2015 and the Manacapuru site at the central Amazon (MAO) in Brazil for two full years from 2014 to 2015. The analysis is done on two regimes: afternoon convective regime and nocturnal precipitation regime. Most models produce afternoon precipitation too early, likely due to the missing transition of shallow-to-deep convection in these models. At SGP, the unified convection schemes better simulate the onset time of precipitation. At MAO, models produce the heating peak in a much lower level compared with observation, indicating too shallow convection in the models. For nocturnal precipitation, models that produce most of nocturnal precipitation all allow convection to be triggered above the boundary layer. This indicates the importance of model capability to detect elevated convection for simulating nocturnal precipitation. Sensitivity studies indicate that (a) nudging environmental variables towards observations has a minor impact on DCP, (b) unified treatment of shallow and deep convection and the capability to capture mid-level convection can help models better capture DCP, and (c) the interactions of the atmosphere with other components in the climate system (e.g. land) are also important for DCP simulations in coupled models. These results provide long-term statistical insights on which physical processes are essential in climate models to simulate DCP.
    • Collaborative Digital Problem‐Solving: Power, Relationships, and Participation

      Jacobs, Gloria E.; Castek, Jill; University of Arizona (Wiley, 2021-12-12)
      The study examines the collaborative nature of problem solving as dyads and triads of adults were grouped to solve digital problems using online resources. Digital problem solving involves the nimble use of skills, strategies, and mindsets to navigate online in everyday contexts using novel resources, tools, and interfaces, in efficient and flexible ways, to accomplish personal and professional goals. Findings address the nature of collaborative talk during digital problem solving through three interrelated categories of themes gleaned from discourse analysis: (a) power, (b) relationships, and (c) participation. These themes offer a nuanced understanding of collaborative interactions during digital problem solving. Implications from this research suggest ways to design collaborative activities and support dialogic interaction, whether among adolescents or adults, during online learning, in formal education settings or informally in other settings where collaboration occurs.
    • A Theory of the Merging Noospheres: Teilhard and Big History

      Campa, Riccardo; Corbally, Christopher; Rappaport, Margaret Boone; Department of Astronomy, University of Arizona (Informa UK Limited, 2021-12-12)
      As the number of detected Earth-like exoplanets keeps increasing, the prospect of contact with extraterrestrial civilizations becomes day after day more plausible. It has been noticed that the encounter between space civilizations implies a fusion of Big Histories. By following Teilhard, the authors argue that the hypothetical contact with alien intelligent life would also result in a merging of the noospheres. The long-term perspective of this process is the awakening of the entire universe. This article provides a history of the idea of noosphere, a reconstruction of Teilhard’s “sociological theory,” and an exploration of the theological consequences of his theory.
    • Arid Ecosystem Vegetation Canopy-Gap Dichotomy: Influence on Soil Microbial Composition and Nutrient Cycling Functional Potential

      Kushwaha, Priyanka; Neilson, Julia W.; Barberán, Albert; Chen, Yongjian; Fontana, Catherine G.; Butterfield, Bradley J.; Maier, Raina M.; Department of Environmental Science, University of Arizona (American Society for Microbiology, 2021-12-11)
      Increasing temperatures and drought in desert ecosystems are predicted to cause decreased vegetation density combined with barren ground expansion. It remains unclear how nutrient availability, microbial diversity, and the associated functional capacity vary between the vegetated canopy and gap soils. The specific aim of this study was to characterize canopy versus gap microsite effect on soil microbial diversity, the capacity of gap soils to serve as a canopy soil microbial reservoir, nitrogen (N)-mineralization genetic potential (ureC gene abundance) and urease enzyme activity, and microbial-nutrient pool associations in four arid-hyperarid geolocations of the western Sonoran Desert, Arizona, United States. Microsite combined with geolocation explained 57% and 45.8% of the observed variation in bacterial/archaeal and fungal community composition, respectively. A core microbiome of amplicon sequence variants was shared between the canopy and gap soil communities; however, canopy soils included abundant taxa that were not present in associated gap communities, thereby suggesting that these taxa cannot be sourced from the associated gap soils. Linear mixed-effects models showed that canopy soils have significantly higher microbial richness, nutrient content, and organic N-mineralization genetic and functional capacity. Furthermore, ureC gene abundance was detected in all samples, suggesting that ureC is a relevant indicator of N mineralization in deserts. Additionally, novel phylogenetic associations were observed for ureC, with the majority belonging to Actinobacteria and uncharacterized bacteria. Thus, key N-mineralization functional capacity is associated with a dominant desert phylum. Overall, these results suggest that lower microbial diversity and functional capacity in gap soils may impact ecosystem sustainability as aridity drives openspace expansion in deserts.
    • Contemporary pregnancy outcomes for women with moderate and severe congenital heart disease

      Kops, Samantha A; Strah, Danielle D; Andrews, Jennifer; Klewer, Scott E; Seckeler, Michael D; Department of Pediatrics, University of Arizona (SAGE Publications, 2021-12-09)
      Background: Women with congenital heart disease (CHD) are surviving into adulthood, with more undergoing pregnancy. Methods: Retrospective review of the Vizient database from 2017–2019 for women 15–44 years old with moderate, severe or no CHD and vaginal delivery or caesarean section. Demographics, hospital outcomes and costs were compared. Results: There were 2,469,117 admissions: 2,467,589 with no CHD, 1277 with moderate and 251 with severe CHD. Both CHD groups were younger than no CHD, there were fewer white race/ethnicity in the no CHD group and more women with Medicare in both CHD groups compared to no CHD. With increasing CHD severity there was an increase in length of stay, ICU admission rates and costs. There were also higher rates of complications, mortality and caesarean section in the CHD groups. Conclusion: Pregnant women with CHD have more problematic pregnancies and understanding this impact is important to improve management and decrease healthcare utilization.
    • Caregiving spouses’ experiences of relational uncertainty and partner influence in the prolonged relational transition of Alzheimer’s disease and related dementias

      Cooper, R. Amanda; Pitts, Margaret J.; Department of Communication, University of Arizona (SAGE Publications, 2021-12-08)
      Alzheimer’s disease and related dementias cause gradual cognitive and communicative decline over a period of several years creating a prolonged transitional period in the lives of people with the disease and their spouse. Relational turbulence theory served as a lens to examine 18 in-depth interviews with caregiving spouses regarding their experiences of relational uncertainty, and interference and facilitation from their partner throughout this prolonged relational transition. Counterintuitively, the experience of relational uncertainty was greatly influenced by the certainties of relational change and termination (death) that shifted the temporal focus of uncertainty to the future. Communicative symptoms and aggressive behavior were a main source of interference. Despite the impairment of the disease, caregiving spouses recognized their partners’ expressions of gratitude, moments of recognition, and simple expressions of love as facilitation.
    • Good Theories in Need of Better Data: Combining Clinical and Social Psychological Approaches to Study the Mechanisms Linking Relationships and Health

      Farrell, Allison K.; Stanton, Sarah C. E.; Sbarra, David A.; Department of Psychology, University of Arizona (SAGE Publications, 2021-12-08)
      The study of intimate relationships and health is a fast-growing discipline with numerous well-developed theories, many of which outline specific interpersonal behaviors and psychological pathways that may give rise to good or poor health. In this article, we argue that the study of relationships and health can move toward interrogating these mechanisms with greater precision and detail, but doing so will require a shift in the nature of commonly used research methods in this area. Accordingly, we draw heavily on the science of behavior change and discuss six key methodologies that may galvanize the mechanistic study of relationships and health: dismantling studies, factorial studies, experimental therapeutics, experimental mediation research, multiple assessments, and recursive modeling. We provide empirical examples for each strategy and outline new ways in which a given approach may be used to study the mechanisms linking intimate relationships and health. We conclude by discussing the key challenges and limitations for using these research strategies as well as novel ideas about how to integrate this work into existing paradigms within the field.
    • Ecological generalism drives hyperdiversity of secondary metabolite gene clusters in xylarialean endophytes

      Franco, Mario E E; Wisecaver, Jennifer H; Arnold, A Elizabeth; Ju, Yu-Ming; Slot, Jason C; Ahrendt, Steven; Moore, Lillian P; Eastman, Katharine E; Scott, Kelsey; Konkel, Zachary; et al. (John Wiley and Sons Inc, 2021-12-07)
      - Although secondary metabolites are typically associated with competitive or pathogenic interactions, the high bioactivity of endophytic fungi in the Xylariales, coupled with their abundance and broad host ranges spanning all lineages of land plants and lichens, suggests that enhanced secondary metabolism might facilitate symbioses with phylogenetically diverse hosts. - Here, we examined secondary metabolite gene clusters (SMGCs) across 96 Xylariales genomes in two clades (Xylariaceae s.l. and Hypoxylaceae), including 88 newly sequenced genomes of endophytes and closely related saprotrophs and pathogens. We paired genomic data with extensive metadata on endophyte hosts and substrates, enabling us to examine genomic factors related to the breadth of symbiotic interactions and ecological roles. - All genomes contain hyperabundant SMGCs; however, Xylariaceae have increased num- bers of gene duplications, horizontal gene transfers (HGTs) and SMGCs. Enhanced metabolic diversity of endophytes is associated with a greater diversity of hosts and increased capacity for lignocellulose decomposition. - Our results suggest that, as host and substrate generalists, Xylariaceae endophytes experi- ence greater selection to diversify SMGCs compared with more ecologically specialised Hypoxylaceae species. Overall, our results provide new evidence that SMGCs may facilitate symbiosis with phylogenetically diverse hosts, highlighting the importance of microbial sym- bioses to drive fungal metabolic diversity.