Now showing items 1-20 of 7851

    • Legitimacy Revisited: Disentangling Propriety, Validity, and Consensus

      Haack, Patrick; Schilke, Oliver; Zucker, Lynne; Univ Arizona (Wiley, 2020-08-15)
      Recent research has conceptualized legitimacy as a multi-level phenomenon comprising propriety and validity. Propriety refers to an individual evaluator's belief that a legitimacy object is appropriate for its social context, whereas validity denotes an institutionalized, collective-level perception of appropriateness. In this article, we refine this multi-level understanding of legitimacy by adding a third, meso-level construct of 'consensus', which we define as the agreement between evaluators' propriety beliefs. Importantly, validity and consensus are distinct and can be incongruent, given that an institutionalized perception can hide underlying disagreement. Disentangling validity from consensus is a crucial extension of the multi-level theory of legitimacy, because it enables an improved understanding of the legitimacy processes that precede sudden and unanticipated institutional change. In particular, while previous works considered revised propriety beliefs as the starting point for institutional change, our account emphasizes that the disclosure of the actual (vs. merely assumed) belief distribution within a social context may instigate institutional change. To study the interplay of propriety, validity, and consensus empirically, we propose a set of experimental designs specifically geared towards improving knowledge of the role of legitimacy and its components in institutional change.
    • Corporate Sociopolitical Activism and Firm Value

      Bhagwat, Yashoda; Warren, Nooshin L.; Beck, Joshua T.; Watson, George F.; Univ Arizona, Mkt (SAGE Publications, 2020-06-29)
      Stakeholders have long pressured firms to provide societal benefits in addition to generating shareholder wealth. Such benefits have traditionally come in the form of corporate social responsibility. However, many stakeholders now expect firms to demonstrate their values by expressing public support for or opposition to one side of a partisan sociopolitical issue, a phenomenon the authors call "corporate sociopolitical activism" (CSA). Such activities differ from commonly favored corporate social responsibility and have the potential to both strengthen and sever stakeholder relationships, thus making their impact on firm value uncertain. Using signaling and screening theories, the authors analyze 293 CSA events initiated by 149 firms across 39 industries, and find that, on average, CSA elicits an adverse reaction from investors. Investors evaluate CSA as a signal of a firm's allocation of resources away from profit-oriented objectives and toward a risky activity with uncertain outcomes. The authors further identify two sets of moderators: (1) CSA's deviation from key stakeholders' values and brand image and (2) characteristics of CSA's resource implementation, which affect investor and customer responses. The findings provide new and important implications for marketing theory and practice.
    • Dynamics of population growth in secondary cities across southern Africa

      Zimmer, Andrew; Guido, Zack; Tuholske, Cascade; Pakalniskis, Alex; Lopus, Sara; Caylor, Kelly; Evans, Tom; Univ Arizona, Sch Geog & Dev; Univ Arizona, Arizona Inst Resilience; Univ Arizona, Sch Nat Resources & Environm (Springer Science and Business Media LLC, 2020-08-08)
      Context Two-fifths of Africans reside in urban areas with populations of less than 250,000. Projections estimate that by 2050 an additional one billion people will live in urban areas, causing an acceleration of growth for these smaller urban areas. While research and development have focused on primary cities with large populations, less is known about the dynamics of urban growth in smaller, "secondary" urban areas (SUA's). Objectives We document the spatial distribution and temporal patterns of SUA's in eight countries across Southern Africa between 1975 and 2015. We further explore the relationships between SUA's growth rates and climate, land use and geographic proximity to other urban areas. Methods Our analysis integrates spatially explicit gridded population, land use, infrastructure and climate datasets. We use descriptive statistics and spatial lag and ordinary least squares regression models to quantify SUA growth rates across three periods and explore factors that are associated with the SUA growth patterns. Results Average SUA growth rates are 2.44% between 1975 and 1990. We show that the climate, distance and land use significantly relate to urbanization trajectories. In addition, we find that the proximity of SUA to the largest cities also significantly relates to urban growth. Conclusions Our results highlight the importance of SUA's within broader African urbanization trends. SUA are undergoing rapid population changes and are important components of economic development processes and livelihoods. Quantifying patterns of SUA urbanization is important for elevating these small but critically important urban areas into the broader context of sustainable urbanization in Africa.
    • Influence of provider recommendations to restart vaccines after childhood cancer on caregiver intention to vaccinate

      Warner, Echo L; Vaca Lopez, Perla L; Kepka, Deanna; Mann, Karely; Kaddas, Heydon K; Fair, Douglas; Fluchel, Mark; Knackstedt, Elizabeth D; Pannier, Samantha T; Martel, Laura; et al. (SPRINGER, 2020-05-26)
      Purpose We studied the influence of oncology and primary care provider (PCP) recommendations on caregiver intentions to restart vaccines (e.g., catch-up or boosters) after cancer treatment. Methods We surveyed primary caregivers ages 18 or older with a child who had completed cancer treatment 3-36 months prior (N= 145) about demographics, child's vaccination status, and healthcare factors (e.g., provider recommendations, barriers, preferences for vaccination). We compared these factors by caregiver's intention to restart vaccines ("vaccine intention" vs. "no intent to vaccinate") using bivariate and multivariable analyses. Results Caregivers were primarily ages 30-39 years (54.9%), mothers (80.6%), college graduates (44.4%), non-Hispanic (89.2%), and married (88.2%). Overall, 34.5% of caregivers did not know which vaccines their child needed. However, 65.5% of caregivers reported vaccine intention. Fewer caregivers with no intention to vaccinate believed that vaccinating their child helps protect others (85.4 vs. 99.0%,p< 0.01), that vaccines are needed when diseases are rare (83.7 vs. 100.0%,p< 0.01), and that vaccines are safe (80.4 vs. 92.6%,p= 0.03) and effective (91.5 vs. 98.9%,p= 0.04) compared with vaccine intention caregivers, respectively. Provider recommendations increased caregivers' likelihood of vaccine intention (oncologist RR = 1.65, 95% CI 1.27-2.12,p< 0.01; PCP RR = 1.51, 95% CI 1.19-1.94,p< 0.01). Conclusions Provider recommendations positively influence caregivers' intention to restart vaccines after childhood cancer. Guidelines are needed to support providers in making tailored vaccine recommendations. Implications for Cancer Survivors Timely vaccination after childhood cancer protects patients against vaccine-preventable diseases during survivorship. Caregivers may benefit from discussing restarting vaccinations after cancer with healthcare providers.
    • Experiences of adolescent witnesses to peer victimization: The bystander effect

      Bauman, Sheri; Yoon, Jina; Iurino, Charlotte; Hackett, Liam; Univ Arizona (PERGAMON-ELSEVIER SCIENCE LTD, 2020-05-19)
      Many anti-bullying programs now emphasize the role of bystanders - youth who witness peer victimization. Using a large sample of adolescents (aged 12-18) from the United Kingdom who completed an online survey, the present study examined the types of bystander interventions, their outcomes, and reasons for intervening and not intervening. No significant group differences by any demographic group were found in intervening or not. Results showed that those who had a negative affective reaction when they witnessed bullying were more likely to intervene. Two intervening behaviors (telling the bully to stop and telling an adult) were the strongest predictors of positive results. The most frequently selected reason for not intervening was not knowing what to do, and for intervening, having prosocial and altruistic motives was most common. These and other results are discussed for theoretical and practical implications.
    • Evaluating provider acceptance of pharmacist interventions in the Discharge Companion Program and its association with readmission reduction

      Jamjoom, Omar; Marupuru, Srujitha; Taylor, Ann M; Warholak, Terri; Scovis, Nicole; Bingham, Jennifer M; Univ Arizona, Coll Pharm, Medicat Management Ctr; Univ Arizona, Coll Pharm, Acad Affairs & Assessment (ELSEVIER, 2020-02-07)
      Objective: To evaluate provider acceptance of pharmacist interventions within the Discharge Companion Program (DCP) and its association with hospital readmissions. Methods: This retrospective record review included patients referred to the DCP between January and October 2018. DCP pharmacists' interventions were assessed for provider acceptance on follow-up consultation or readmission. A chi-square test assessed the association between provider acceptance, communication modality, and technology used. A logistic regression model assessed the association between readmission risk and variables of interest. An a priori alpha level of 0.05 was used. Results: Of the 197 patients referred to the DCP, 102 met inclusion criteria. DCP pharmacists made a total of 271 interventions; 185 (68.7%) required provider action. The most common intervention type was medication addition or discontinuation (n = 74, 40%); the communication mode was between DCP nurses and primary care provider offices or skilled nursing facilities (n = 56, 54.9%); and the preferred technology was the telephone (n = 58, 56.9%). Provider acceptance rate was 30.8% (n = 57) of actionable interventions, although it was not significantly associated with 30-day readmission reductions (P = 0.833) and did not differ significantly when interventions were communicated to other health care professionals (P = 0.53). The specific intervention communication mode (i.e., telephone, facsimile, or both) of pharmacist interventions did not significantly affect provider acceptance (P = 0.133). The overall readmission rate was 22.5% (n = 23), and the only significant predictor of 30-day readmission was the number of comorbidities (odds ratio 1.28 [95% CI 1.03-1.58], P = 0.024). Conclusion: Provider acceptance of pharmacists' interventions did not significantly affect 30-day readmission rates, regardless of communication mode (telephone or facsimile) or technology used. However, the DCP successfully identified numerous medication-related problems. Further study is warranted regarding provider acceptance of pharmacist recommendations on 30-day readmission reduction. (C) 2020 American Pharmacists Association (R). Published by Elsevier Inc. All rights reserved.
    • Simplified Flip-Flop Gate Model for EEMI Injection

      Valbuena, Luis; Heileman, Gregory L.; Hemmady, Sameer; Schamiloglu, Edl; Univ Arizona (IEEE, 2019-09)
      We present a second order dynamical system to represent the behavior of a D flip-flop. We employ windowing functions and vector fields to replicate a characteristic found in [1],which resorts to switching. The model also takes into account metastable behavior, which can be exploited when studying software execution faults due to an undefined logical state. We conceived the noise injection to be additive noise targeting the transition between the stable equilibrium points. However, the model is flexible and many parameters can be changed to alter its behavior.
    • A Hamilton-Jacobi Equation for Evaluating EEMI Propagation in a Computing System

      Valbuena, Luis; Heileman, Gregory L.; Hemmady, Sameer; Schamiloglu, Edl; Univ Arizona (IEEE, 2019-09)
      In this paper, we present a theoretical framework for modeling the empirically observed cascading of software failures on a complicated computing system exposed to extreme electromagnetic interference (EEMI). Our approach is to treat the temporal evolution of the electromagnetic coupling and the resultant cascading series of electromagnetic-induced faults as the "flow" in a dynamic fluid-mechanical system and thereby utilize aspects of the Navier Stokes and Hamilton-Jacobi equations to predict the rate of this flow. Therefore, inspired by the concepts of fluid dynamics [1], we include a diffusion term in the Hamilton-Jacobi-Isaacs (HJI) equation. We have considered two approaches. In one we apply a Taylor expansion to the optimality principle and consider additional terms; in the other scenario, we simply add a diffusion term in the form of a Laplacian applied to the cost function H(x,...) and some constant c, as it is present in the Navier-Stokes equation for incompressible flow. We provide numerical comparisons for both approaches with respect to the original HJI equation where the dynamical vector field corresponds to analytical models of a NOR logic gate. This model is a second-order differential equation that describes the behavior of the gate that incorporates a new term accounting for EEMI injection.
    • A Log-Likelihood Ratio based Generalized Belief Propagation

      Amaricai, Alexandru; Bahrami, Mohsem; Vasic, Bane; Univ Arizona (IEEE, 2019-07)
      In this paper, we propose a reduced complexity Generalized Belief Propagation (GBP) that propagates messages in Log-Likelihood Ratio (LLR) domain. The key novelties of the proposed LLR-GBP are: (i) reduced fixed point precision for messages instead of computational complex floating point format, (ii) operations performed in logarithm domain, thus eliminating the need for multiplications and divisions, (iii) usage of message ratios that leads to simple hard decision mechanisms. We demonstrated the validity of LLR-GBP on reconstruction of images passed through binary-input two-dimensional Gaussian channels with memory and affected by additive white Gaussian noise.
    • Levels and volatility in daily relationship quality: Roles of daily sacrifice motives

      Kayabol, Nazlı Büşra Akçabozan; Gonzalez, Jose-Michael; Gamble, Hilary; Totenhagen, Casey J.; Curran, Melissa A.; Univ Arizona (SAGE Publications, 2020-08-13)
      Conflicts are inevitable in romantic relationships. Couples sometimes choose the pro-relationship strategy of relational sacrifice to address such conflicts. Previous research established that examining sacrifice motives (i.e., approach and avoidance) is meaningful in understanding relationship quality. Using interdependence theory and 14 days of diaries with 110 heterosexual couples, we extend previous research by testing how sacrifice motives predicted both mean levels and volatility of daily relationship quality (i.e., satisfaction, commitment, intimacy, passion, trust, and love). Specifically, we examined actor and partner reports of sacrifice motives as individuals' average levels (trait; between-person differences) and daily levels of sacrifice motives on a specific day (state; within-person differences) in predicting relationship quality. When predictingmean levelsof relationship quality, individuals' own (actor) trait and state approach and avoidance motives predicted most relationship quality variables. Results were less robust for partner effects, especially for partner trait and state approach motives. When predictingvolatility(within-person variability across 14 days) in relationship quality, patterns were more robust for both approach and avoidant motives and for both actor and partner effects. For approach sacrifices, and for all six relationship quality variables, individuals' trait approach motives predicted lower volatility, whereas avoidance motives predicted higher volatility. For partner effects, individuals reported lower volatility in satisfaction, intimacy, passion, and trust when their partners were higher in approach motives, whereas they reported higher volatility in satisfaction, commitment, intimacy, and trust when their partners were higher in avoidance motives. We discuss the importance of studying dyads and testing the associations between sacrifice motives and daily relationship quality-both levels and volatility.
    • Testing relationships between smartphone engagement, romantic partner communication, and relationship satisfaction

      Lapierre, Matthew A.; Custer, Benjamin E.; Univ Arizona, Dept Commun (SAGE Publications, 2020-07-21)
      As smartphone technology has spread rapidly across the globe, growing concern has spotlighted how these devices can limit the quality of our communication with others and harm interpersonal relationships. The current study examined how self-reported smartphone use and smartphone dependency were associated with romantic partner communication, and how these variables subsequently tied to relationship satisfaction. Working with a sample of 433 American young adults in romantic relationships, the study found that smartphone use was associated with increased communication between romantic partners, and increased mediated communication between partners predicted more affectionate communication. Conversely, increased smartphone dependency was directly associated with less affectionate communication and lower relationship satisfaction. The study offers insights into how smartphones potentially affect how we connect with romantic partners.
    • Combined nocturnal pulse oximetry and questionnaire-based obstructive sleep apnea screening - A cohort study

      Mashaqi, Saif; Staebler, Danelle; Mehra, Reena; Univ Arizona, Coll Med, Dept Internal Med, Banner Univ Med Ctr, Div Pulm Crit Care & Sleep Med (ELSEVIER, 2020-04-03)
      We conducted a retrospective cohort study. We reviewed the electronic medical records of 130 patients who were referred to Sanford sleep center from both inpatient and outpatient settings over one year (August 1st, 2016 to August 1st, 2017). Nocturnal oximetry was conducted at home (in the outpatient group) and in the medical wards (in the inpatient group), and the following measures were obtained: Oxygen Desaturation Index (ODIPOx), mean SaO2POx and time spent below 88% SaO2 (T88Pox). Apnea-hypopnea index (AHI), mean SaO2PSG, and T88PSG from overnight polysomnography (PSG) and STOP-BANG score.
    • Meso-Cenozoic multiple exhumation in the Shandong Peninsula, eastern North China Craton: Implications for lithospheric destruction

      Yang, Fan; Santosh, M.; Glorie, Stijn; Jepson, Gilby; Xue, Fei; Kim, Sung Won; Univ Arizona, Dept Geosci (Elsevier BV, 2020-10)
      The Shandong Peninsula in the eastern North China Craton (NCC) forms part of the region that witnessed extensive tectonic reactivation with concomitant craton destruction and lithospheric thinning during the Meso-Cenozoic. Previous studies concentrated mainly on the timing, mechanism and tectonic setting of the Meso-Cenozoic magmatism, with inadequate evidence from low temperature thermochronology to constrain the thermo-tectonic exhumation history of this region. In this study, we present new apatite U-Pb (AUPb) and fission track (AFT) data with corresponding thermal history models for igneous rocks from the two flanks of the Tan-Lu Fault Zone (TLFZ) that bisects the Shandong Peninsula, with a view to gain insights into the Meso-Cenozoic exhumation history of this region and to evaluate its implications on the lithospheric destruction of the NCC. The newly obtained AUPb ages of 2.5-1.5 Ga for the Precambrian intrusive rocks and of 162-112 Ma for the Mesozoic igneous suite are mainly used to constrain their thermal history models. In addition, the Mesozoic AUPb ages of 162-112 Ma highly overlap with their corresponding zircon U-Pb ages (161-115 Ma), suggesting shallow granitoid emplacement and associated rapid post-magmatic cooling in response to the westward subduction of the Paleo-Pacific Plate. The AFT dating results yield two groups of AFT central ages at 122-113 Ma and 98-59 Ma, and corresponding thermal history models also reveal two rapid cooling stages during the Early Cretaceous (130-105 Ma) and Late Cretaceous to Paleogene (85-55 Ma). By integrating previous low temperature therrmx:hronological studies with this study, we interpret that the Early Cretaceous rapid exhumation corresponds to the peak timing of craton destruction, resulting from the Paleo-Pacific slab rollback within a back-arc extensional setting. The Late Cretaceous rapid exhumation is interpreted as a response to continuing craton destruction, derived by the NNW-directed Pacific Plate subduction.The Paleogene cooling might represent the termination of craton destruction of Shandong Peninsula associated with a dextral motion along the TLFZ, triggered by the change in direction of the Pacific Plate from NNW to WNW and/or far-field effect of the India-Eurasia collision. (C) 2020 Elsevier B.V. All lights reserved.
    • Investigation of Single-Case Multiple-Baseline Randomization Tests of Trend and Variability

      Levin, Joel R.; Ferron, John M.; Gafurov, Boris S.; Univ Arizona (Springer Science and Business Media LLC, 2020-08-04)
      Previous simulation studies of randomization tests applied in single-case educational intervention research contexts have typically focused on A-to-B phase changes in means/levels. In the present simulation study, we report the results of two multiple-baseline investigations, one targeting between-phase changes in slopes/trends and the other targeting between-phase changes in variability. For each of these measures, we examine the comparative type I errors and powers of several randomization test procedures that have previously appeared in the literature. In so doing, we propose an alternative measure of variability that is more sensitive to detecting between-phase change than is the variance itself. We conclude by providing a summary table of recommended randomization test procedures for assessing different types of intervention-based effects associated with level, trend, and variability.
    • The making of Class C fly ash as high-strength precast construction material through geopolymerization

      Zhang, Jinhong; Feng, Qingming; Univ Arizona, Dept Min & Geol Engn (Springer Science and Business Media LLC, 2020-08-17)
      A study has been carried out to apply fly ash as a high strength, water-resistant precast construction material through geopolymerization. Experiment results show that the working conditions such as water content, the concentration of NaOH, curing temperature, and curing time significantly affect the mechanical property of geopolymer matrix. Through optimization, an above-100 MPa compressive strength has been achieved with the geopolymerization products. The optimum working conditions involves 10 M NaOH concentration, 14-15% water content, and curing at 90 degrees C in an oven for 1 day or at ambient condition for 3 weeks. Adding Ca(OH)(2)does not help to increase the compressive strength of the specimen. Water soaking tests show that the geopolymerization product has a very high water resistance without losing noticeable compressive strength, even after a 1-month soaking time. To elucidate the geopolymerization mechanism, microscopic techniques such as SEM/EDS (scanning electron microscopy and energy-dispersive X-ray spectroscopy), XRD (X-ray diffraction) and ATR-FTIR (attenuated total reflectance Fourier transform infrared) are also applied to investigate the microstructure, the elemental and phase composition of geopolymerization products. The findings of the present work provide a novel method for applying fly ash as a high-strength water-resistant precast construction material.
    • Finite Alphabet Iterative Decoding of LDPC Codes with Coarsely Quantized Neural Networks

      Xiao, Xin; Vasic, Bane; Tandon, Ravi; Lin, Shu; Univ Arizona (IEEE, 2019-12)
      In this paper, we introduce a method of using quantized neural networks (QNN) to design finite alphabet message passing decoders (FAID) for Low-Density Parity Check (LDPC) codes. Specifically, we construct a neural network with low precision activations to optimize a FAID over Additive White Gaussian Noise Channel (AWGNC). The low precision activations cause a critical issue that their gradients vanish almost everywhere, making it difficult to use classical backward propagation. We introduce straight-through estimators (STE) [1] to avoid this problem, by replacing zero derivatives of quantized activations with surrogate gradients in the chain rules. We present a systematic approach to train such networks while minimizing the bit error rate, which is a widely used and accurate metric to measure the performance of iterative decoders. Examples and simulations show that by training a QNN, a FAID with 3-bit of message and 4-bit of channel output can be obtained, which performs better than the more complex floating-point minsum decoding algorithm. This methodology is promising in the sense that it facilitates designing low-precision FAID for LDPC codes while maintaining good error performance in a flexible and efficient manner.
    • Diagnosing collisionless energy transfer using field–particle correlations: Alfvén-ion cyclotron turbulence

      Klein, Kristopher G.; Howes, Gregory G.; TenBarge, Jason M.; Valentini, Francesco; Univ Arizona, Lunar & Planetary Lab (Cambridge University Press (CUP), 2020-07-24)
      We apply field-particle correlations - a technique that tracks the time-averaged velocity-space structure of the energy density transfer rate between electromagnetic fields and plasma particles - to data drawn from a hybrid Vlasov-Maxwell simulation of Alfven-ion cyclotron turbulence. Energy transfer in this system is expected to include both Landau and cyclotron wave-particle resonances, unlike previous systems to which the field-particle correlation technique has been applied. In this simulation, the energy transfer rate mediated by the parallel electric field E-parallel to comprises approximately 60% of the total rate, with the remainder mediated by the perpendicular electric field E-perpendicular to. The parallel electric field resonantly couples to protons, with the canonical bipolar velocity-space signature of Landau damping identified at many points throughout the simulation. The energy transfer mediated by E-perpendicular to preferentially couples to particles with v(tp) less than or similar to v(perpendicular to) less than or similar to 3 v(tp), where vtp is the proton thermal speed, in agreement with the expected formation of a cyclotron diffusion plateau. Our results demonstrate clearly that the field-particle correlation technique can distinguish distinct channels of energy transfer using single-point measurements, even at points in which multiple channels act simultaneously, and can be used to determine quantitatively the rates of particle energization in each channel.
    • Achieving Participation-Focused Intervention Through Shared Decision Making: Proposal of an Age- and Disorder-Generic Framework

      Baylor, Carolyn; Darling-White, Meghan; Univ Arizona, Dept Speech Language & Hearing Sci (AMER SPEECH-LANGUAGE-HEARING ASSOC, 2020-08)
      Introduction: The World Health Organization's International Classification of Functioning, Disability and Health calls on speech-language pathologists (SLPs) to provide care that impacts all aspects of an individual's experience with a communication disorder, including their participation in valued life situations. However, SLPs often report feeling unprepared to implement and document interventions that target life participation. The purpose of this article is to propose a framework to guide participation-focused intervention practices. This age- and disorder-generic framework is designed to be applicable with clients across the variety of settings in which SLPs work. Method: In this clinical focus article, we draw on past research and clinical experience to propose a restructuring of World Health Organization's International Classification of Functioning, Disability and Health components such that participation is the primary focus and outcomes indicator for intervention. In this framework, a specific communicative participation situation is identified and assessed quantitatively, and a corresponding participation-focused goal is established through shared decision making. Following that, assessments are conducted and goals are established in the areas of communication skills, physical and social environments, and personal perspectives. Results: The proposed framework provides a concrete organizational structure as well as assessment, goal-writing, and intervention examples to assist SLPs in translating theoretical biopsychosocial frameworks into clinical practices. Conclusions: SLPs can and do provide holistic communication services to clients to help them achieve their life participation goals. This article provides an example as to how we can document the need for, as well as the value and impact of our important work, meeting the diverse life participation needs of clients.
    • Evaluating the potential of treated effluent as novel habitats for aquatic invertebrates in arid regions

      Eppehimer, Drew E.; Hamdhani, Hamdhani; Hollien, Kelsey D.; Bogan, Michael T.; Univ Arizona, Sch Nat Resources & Environm (Springer Science and Business Media LLC, 2020-07-08)
      Increasing anthropogenic demands for freshwater have altered many aquatic systems, including the drying of formerly perennial streams. The discharge of treated effluent has returned perennial flow in some of these streams, especially in arid and semi-arid regions, but the ability of treated effluent to support diverse aquatic communities is poorly understood. We examined the potential of treated effluent to create aquatic invertebrate habitat using the effluent-dependent Santa Cruz River in southern Arizona, USA as a case study. We identified 92 invertebrate taxa across our ten sampling sites and two sampling dates. Community composition was primarily shaped by water quality but also by stream drying (on daily time scales) and benthic substrate. Specifically, Linear Mixed-Effects models revealed a strong positive relationship between dissolved oxygen and taxonomic richness and a strong negative relationship between stream drying and invertebrate density. Although there are unique challenges to biota in effluent-dependent systems, our results suggest that treated wastewater could be managed to augment or recreate aquatic habitats that have been otherwise diminished or lost.
    • Rancher perceptions of and attitudes toward Mexican gray wolves: An exploration of community dialogue

      Waters, Kaycie M.; Mars, Matthew M.; Univ Arizona, Dept Agr Educ Technol & Innovat (Informa UK Limited, 2020-07-12)
      Many socio-political issues arise when predators, like the endangered Mexican gray wolf, are reintroduced into areas that are concurrently used by ranchers. There is a gap in understanding of how public dialogue convey and perpetuate the perceptions and attitudes agriculturalists hold toward predator reintroduction efforts. Our study explores how ranchers' use of social media and interactive communication relate to this topic. Our analysis is guided by the following three theoretical elements of online communities: intellectual, social, and cultural. A qualitative design is used to explore the dialogue that conveys and perpetuates ranchers' perceptions and attitudes to the wolf reintroduction. The cultural element-type tends to have the most influence on how information is received via online communities. This creates a cultural echo chamber, where the expression of outside views leads to defensive discussion that strengthens the culture of the community rather than foster its evolution.