• 4D Reconstruction and Identification of Carotid Artery Stenosis Utilizing a Novel Pulsatile Ultrasound Phantom

      Thurgood, Harrison; Witte, Russell; Laksari, Kaveh; Department of Aerospace and Mechanical Engineering, University of Arizona; Department of Biomedical Engineering, University of Arizona; Department of Medical Imaging, University of Arizona (Wiley, 2021-10-22)
      As a major application focus of vascular ultrasonography, the carotid artery has long been the subject of phantom design and procedure focus. It is therefore important to devise procedures that are minimally invasive and informative, initially using a physiologically accurate anthropomorphic phantom to validate the methodology. In this article, a novel phantom design protocol is presented that enables the efficient production of a pulsatile ultrasound phantom consisting of soft and vascular tissue mimics, as well as a blood surrogate fluid. These components when combined give the phantom high acoustic compatibility and lifelike mechanical properties. The phantom was developed using "at-home" purchasable components and 3D printing technology. The phantom was subsequently used to develop a 4D reconstruction algorithm of the pulsing vessel in MATLAB. In pattern with recent developments in medical imaging, the 4D reconstruction enables clinicians to view vessel wall motion in a 3D space without the need for manual intervention. The reconstruction algorithm also produces measured inner luminal areas and vessel wall thickness, providing further information relating to structural properties and stenosis, as well as elastic properties such as arterial stiffness, which could provide helpful markers for disease diagnosis. Basic Protocol 1: Constructing a pulsatile ultrasound phantom model. Support Protocol: Creating a vascular mimic mold. Basic Protocol 2: Creating a 4D reconstruction from ultrasound frames.
    • Abdominal T2‐Weighted Imaging and T2 Mapping Using a Variable Flip Angle Radial Turbo Spin‐Echo Technique

      Keerthivasan, Mahesh B.; Galons, Jean‐Philippe; Johnson, Kevin; Umapathy, Lavanya; Martin, Diego R.; Bilgin, Ali; Altbach, Maria I.; Department of Medical Imaging, University of Arizona; Department of Electrical and Computer Engineering, University of Arizona; Department of Biomedical Engineering, University of Arizona (Wiley, 2021-07-13)
      Background: T2 mapping is of great interest in abdominal imaging but current methods are limited by low resolution, slice coverage, motion sensitivity, or lengthy acquisitions. Purpose: Develop a radial turbo spin-echo technique with refocusing variable flip angles (RADTSE-VFA) for high spatiotemporal T2 mapping and efficient slice coverage within a breath-hold and compare to the constant flip angle counterpart (RADTSE-CFA). Study Type: Prospective technical efficacy. Subjects: Testing performed on agarose phantoms and 12 patients. Focal liver lesion classification tested on malignant (N = 24) and benign (N = 11) lesions. Field Strength/Sequence: 1.5 T/RADTSE-VFA, RADTSE-CFA. Assessment: A constrained objective function was used to optimize the refocusing flip angles. Phantom and/or in vivo data were used to assess relative contrast, T2 estimation, specific absorption rate (SAR), and focal liver lesion classification. Statistical Tests: t-Tests or Mann–Whitney Rank Sum tests were used. Results: Phantom data did not show significant differences in mean relative contrast (P = 0.10) and T2 accuracy (P = 0.99) between RADTSE-VFA and RADTSE-CFA. Adding noise caused T2 overestimation predominantly for RADTSE-CFA and low T2 values. In vivo results did not show significant differences in mean spleen-to-liver (P = 0.62) and kidney-to-liver (P = 0.49) relative contrast between RADTSE-VFA and RADTSE-CFA. Mean T2 values were not significantly different between the two techniques for spleen (T2VFA = 109.2 ± 12.3 msec; T2CFA = 110.7 ± 11.1 msec; P = 0.78) and kidney-medulla (T2VFA = 113.0 ± 8.7 msec; T2CFA = 114.0 ± 8.6 msec; P = 0.79). Liver T2 was significantly higher for RADTSE-CFA (T2VFA = 52.6 ± 6.6 msec; T2CFA = 60.4 ± 8.0 msec) consistent with T2 overestimation in the phantom study. Focal liver lesion classification had comparable T2 distributions for RADTSE-VFA and RADTSE-CFA for malignancies (P = 1.0) and benign lesions (P = 0.39). RADTSE-VFA had significantly lower SAR than RADTSE-CFA increasing slice coverage by 1.5. Data Conclusion: RADTSE-VFA provided noise-robust T2 estimation compared to the constant flip angle counterpart while generating T2-weighted images with comparable contrast. The VFA scheme minimized SAR improving slice efficiency for breath-hold imaging. Level of Evidence: 2. Technical Efficacy Stage: 1.
    • Adaptive management in a conservation breeding program: Mimicking habitat complexities facilitates reproductive success in narrow‐headed gartersnakes (Thamnophis rufipunctatus)

      Blais, Brian R.; Wells, Stuart A.; Poynter, Bradley M.; Koprowski, John L.; Garner, Michael M.; Allard, Ruth A.; School of Natural Resources and the Environment, University of Arizona (Wiley, 2022-01-17)
      Mimicking natural parameters and complexities in zoo conservation breeding programs can facilitate natural physiological and behavioral traits, which in turn can inform more effective species reintroduction efforts. To curtail population declines of threatened narrow-headed gartersnakes (Thamnophis rufipunctatus), the Arizona Center for Nature Conservation/Phoenix Zoo partnered with a multiagency conservation working group to develop an ex situ propagation-for-release program. Initially, Zoo staff followed common snake husbandry protocols of manually inducing brumation (i.e., winter dormancy). Copulation was observed during the first few years, but no births resulted. Also, some older individuals developed post-brumation health abnormalities, prompting a strategic reassessment. To facilitate propagation and improve health, Zoo staff applied ecological knowledge of T. rufipunctatus and an adaptive management strategy to implement key parameters for success: sociality, refugia, breeding and foraging behaviors, and natural brumation. Zoo staff developed a large multisnake enclosure that mimicked natural ecological and habitat complexities including a hibernaculum to stimulate natural brumation. Gartersnakes were left mostly unimpeded to conduct natural behaviors across seasons in the enriched environment. We referenced change in body mass after ten brumation periods as a proxy for health. Under natural brumation, gartersnakes did not lose body mass, and this shift resulted in fully ex situ parturition events—the first for this imperiled species. We highlight the efficacy of adaptive management and incorporation of natural parameters and environmental complexities into conservation breeding programs. These actions can improve the health and success of animals under managed care—processes applicable to a range of taxa targeted for conservation translocations.
    • Aligning green infrastructure to sustainable development: A geographical contribution to an ongoing debate

      de Vito, Laura; Staddon, Chad; Zuniga‐Teran, Adriana A.; Gerlak, Andrea K.; Schoeman, Yolandi; Hart, Aimee; Booth, Giles; Udall Center for Studies in Public Policy, University of Arizona; School of Landscape Architecture and Planning, University of Arizona; School of Geography and Development, University of Arizona (Wiley, 2021-11-29)
      Blue and green infrastructure (BGI) is increasingly viewed as a promising solution to promoting a shift beyond traditionally engineered “grey” approaches towards more socially and environmentally sustainable infrastructure systems. The specific insights of geographical scholarship on how to address issues of processes, scale, and place in BGI design, implementation, and long-term management would help unlock the potential for BGI to be appropriate and inclusive, as well as support environmentally sound solutions. In this paper we unpack issues of processes for inclusive decision-making to design and implement BGI projects that can advance sustainable development. We present an assessment framework and its application to two case studies that highlight the potential for better alignment of BGI projects to the three pillars of sustainable development and that reveal key research challenges that geographical scholarship could address. We believe that co-produced geographical research in this domain is well placed to tackle these research challenges. 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).
    • All in the timing: Epigenetic control of greening

      Woodson, Jesse D; School of Plant Sciences, University of Arizona (Wiley, 2021-06-14)
    • Alteration of fibrin hydrogel gelation and degradation kinetics through addition of azo dyes

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

      Ryan, Andrew J.; Whipple, Kelin X.; Univ Arizona, Lunar & Planetary Lab (Wiley, 2020-08-25)
      Amphitheater-headed canyons are common on Earth and Mars and researchers have long sought to draw inferences about canyon-forming processes from the morphology of canyon heads and associated knickpoints, often suggesting that amphitheater heads indicate erosion by groundwater seepage erosion. However, the conditions and processes that lead to amphitheater-headed canyon formation have been debated for many years. We consider two hypotheses that attribute the amphitheater-headed canyon formation to fluvial erosion of strong-over-weak stratigraphy or, alternatively, groundwater spring discharge and seepage erosion. A spatial analysis of canyon-form distribution with respect to local stratigraphy along the Escalante River and on Tarantula Mesa, Utah, indicates that canyon form is most closely related to variations in local sedimentary rock strata, rather than inferred groundwater spring intensity. Lateral facies variations that affect the continuity of strong layers can induce or disrupt the formation of amphitheaters. Furthermore, we find that amphitheater retreat rate is dictated by the interaction of fluvial processes downstream of the amphitheater headwalls and stratigraphy, rather than waterfall and groundwater processes that likely importantly influence headwall form. We conclude that fluvial erosion of strong-over-weak stratigraphic layering alone is sufficient to form amphitheaters at knickpoints and canyon heads. Thus, we re-affirm that formation process should not be inferred from canyon-head morphology, particularly where a strong-over-weak layering is known or plausible.
    • Analysis and experimental investigation of Apollo sample 12032,366-18, a chemically evolved basalt from the Moon

      Stadermann, Amanda C; Jolliff, Bradley L; Krawczynski, Michael J; Hamilton, Christopher W.; Barnes, Jessica J.; Lunar and Planetary Laboratory, University of Arizona (Wiley, 2022)
      Sample 12032,366-18 is a 41.2 mg basaltic rock fragment collected during the Apollo 12 mission to the Moon. It is enriched in incompatible trace elements (e.g., 7 ppm Th), but does not have a bulk composition that would be considered a KREEP (enriched in potassium, rare earth elements, and phosphorous) basalt. The sample is of particular interest because it may be representative of some of the mare basalts within Oceanus Procellarum that are inferred to be Th-rich, based on remote sensing data. The major mineral assemblage of 12032,366-18 is pyroxene, plagioclase, olivine, and ilmenite, and the bulk composition has 4.2 wt% TiO2, 11.7 wt% Al2O3, and 0.25 wt% K2O. The sample contains regions of late-stage crystallized minerals and glass (collectively termed mesostasis), including K-feldspar, apatite, rare earth (RE) merrillite, ilmenite, troilite, silica, and relatively sodic plagioclase adjacent to ferroan pyroxene. The mesostasis also occurs in several areas that are highly enriched in silica and intergrown with K-feldspar and very fine-grained, high-mean-atomic-number phases. We explore the petrology of this sample, including the origin of the Si-K-rich mesostasis to assess whether the mesostasis had formed by silicate liquid immiscibility (SLI). We used experiments to determine if the bulk composition of 12032,366-18 is representative of a bulk liquid composition, how the residual liquid evolves, and to investigate the partitioning of elements between phases as the melt evolves. Experiments support that the mesostasis formed by SLI after crystallization of minerals closely matches the major-mineral assemblage of 12032,366-18. Experiments bracket the onset of SLI and merrillite saturation between 1024 and 1002 °C. Some high field strength elements, such as Zr and P, partition preferentially into the Fe-rich liquid. From the experiments, we infer that the bulk composition of 12032,366-18 represents the magma from which it crystallized. Based on the Th-rich and KREEP-bearing chemistry of this sample, along with experimental evidence showing that the sample is representative of a bulk liquid composition and not a cumulate, we conclude that basalt fragment 12032,366-18 was delivered to the Apollo 12 landing site as ejecta from a distant impact and could represent an Oceanus Procellarum basalt. Missions to Oceanus Procellarum, such as Chang’E 5, have the potential to confirm whether some of those basalts are indeed enriched in Th and other incompatible trace elements as indicated by remote sensing.
    • Analysis of impacts of inflation on the distribution of household consumption expenditures

      Taylor, Lester D.; College of Agriculture and Life Sciences, University of Arizona (Wiley, 2022-08-09)
      As a consequence of the COVID-19 pandemic of early 2020, production in the United States, as in much of the world, largely came to a standstill. Unemployment in the United States quickly rose from 3.5% in February to 13.2% in May, quarter-to-quarter GDP fell 7.8%, and substantial transfers were enacted to maintain household income. The resulting mismatch between aggregate supply and demand not surprisingly ignited an inflation that by early 2022 had reached a year-over-year 40-year high. The purpose of the present communication is to utilize a framework developed from data embodied in surveys of households’ consumer expenditures to analyze impacts of this inflation on separate categories of expenditure. The engine for the analysis, whose construction is described in detail by Taylor (2013, is a matrix of “intra-budget” coefficients that represent the direct relationships amongst different categories of expenditure in households’ budgets. The elements of this matrix are constructed from the information in 58 quarters of data (2006 through 2019) from the ongoing BLS Survey of Consumer Expenditure to analyze effects and impacts on 16 categories of US household consumption expenditure of the 2021–2022 inflation. Principal findings include: expenditures for housing, transportation, gasoline and oil, and personal insurance consistently endure the largest impacts from inflation; real- income effects from inflation differ from those arising from a like cut in nominal income; not surprisingly, food expenditures are most impacted at low income.
    • Association between the polymorphism of three genes involved in the methylation and efflux of arsenic (As3MT, MRP1, and P‐gp) with lung cancer in a Mexican cohort

      Recio‐Vega, Rogelio; Hernandez‐Gonzalez, Sandra; Michel‐Ramirez, Gladis; Olivas‐Calderón, Edgar; Lantz, R. Clark; Gandolfi, A. Jay; Amistadi, Mary Kay; Southwest Environmental Health Science Center, University of Arizona; Department of Cellular and Molecular Medicine, University of Arizona (Wiley, 2020-12-19)
      Lung cancer is the most common neoplasm and the primary cause-related mortality in developed and in most of nondeveloped countries. Epidemiological studies have demonstrated that even at low arsenic doses, the lungs are one of the main target organs and that chronic arsenic exposure has been associated with an increase in lung cancer development. Among the risk factors for cancer, arsenic methylation efficiency (As3MT) and the clearance of arsenic from cells by two members of the ATP-binding cassette (ABC) transporter family (multidrug resistance protein 1 [MRP1] and P-glycoprotein [P-gp]) play an important role in processing of arsenic and decreasing its intracellular levels. This study aimed to evaluate the association between chronic exposure to arsenic with polymorphism of three proteins involved in arsenic metabolism and efflux of the metalloid in subjects with lung cancer. Polymorphism in As3MT, MRP1, and P-gp modified the arsenic metabolism increasing significantly the AsV urinary levels. A significant association between MRP1 polymorphisms with an increase in the risk for cancer was found. The high inorganic arsenic urinary levels registered in the studied subjects suggest a reduction in the efficiency of As3MT, MRP1, and P-gp firstly because of gene polymorphisms and secondarily because of high internal inorganic arsenic levels. MRP1 polymorphism was associated with a twofold increase in the risk of lung cancer. © 2020 John Wiley & Sons, Ltd.
    • Benchmark dose risk analysis with mixed‐factor quantal data in environmental risk assessment

      Sans‐Fuentes, Maria A.; Piegorsch, Walter W.; BIO5 Institute and Graduate Interdisciplinary Program in Statistics & Data Science, University of Arizona; BIO5 Institute, Department of Mathematics, and Graduate Interdisciplinary Program in Statistics & Data Science, University of Arizona (Wiley, 2021-03-09)
      Benchmark analysis is a general risk estimation strategy for identifying the benchmark dose (BMD) past which the risk of exhibiting an adverse environmental response exceeds a fixed, target value of benchmark response. Estimation of BMD and of its lower confidence limit (BMDL) is well understood for the case of an adverse response to a single stimulus. In many environmental settings, however, one or more additional, secondary, qualitative factor(s) may collude to affect the adverse outcome, such that the risk changes with differential levels of the secondary factor. This article extends the single-dose BMD paradigm to a mixed-factor setting with a secondary qualitative factor possessing two levels. With focus on quantal-response data and using a generalized linear model with a complementary-log link function, we derive expressions for BMD and BMDL. We study the operating characteristics of six different multiplicity-adjusted approaches to calculate the BMDL, using Monte Carlo evaluations. We illustrate the calculations via an example dataset from environmental carcinogenicity testing. © 2021 John Wiley & Sons, Ltd.
    • Beyond ecosystem modeling: A roadmap to community cyberinfrastructure for ecological data‐model integration

      Fer, Istem; Gardella, Anthony K.; Shiklomanov, Alexey N.; Campbell, Eleanor E.; Cowdery, Elizabeth M.; De Kauwe, Martin G.; Desai, Ankur; Duveneck, Matthew J.; Fisher, Joshua B.; Haynes, Katherine D.; et al. (Wiley, 2020-10-19)
      In an era of rapid global change, our ability to understand and predict Earth's natural systems is lagging behind our ability to monitor and measure changes in the biosphere. Bottlenecks to informing models with observations have reduced our capacity to fully exploit the growing volume and variety of available data. Here, we take a critical look at the information infrastructure that connects ecosystem modeling and measurement efforts, and propose a roadmap to community cyberinfrastructure development that can reduce the divisions between empirical research and modeling and accelerate the pace of discovery. A new era of data‐model integration requires investment in accessible, scalable, and transparent tools that integrate the expertise of the whole community, including both modelers and empiricists. This roadmap focuses on five key opportunities for community tools: the underlying foundations of community cyberinfrastructure; data ingest; calibration of models to data; model‐data benchmarking; and data assimilation and ecological forecasting. This community‐driven approach is a key to meeting the pressing needs of science and society in the 21st century.
    • Biallelic AOPEP Loss‐of‐Function Variants Cause Progressive Dystonia with Prominent Limb Involvement

      Zech, Michael; Kumar, Kishore R.; Reining, Sophie; Reunert, Janine; Tchan, Michel; Riley, Lisa G.; Drew, Alexander P.; Adam, Robert J.; Berutti, Riccardo; Biskup, Saskia; et al. (Wiley, 2021-10)
      Background: Monogenic causes of isolated dystonia are heterogeneous. Assembling cohorts of affected individuals sufficiently large to establish new gene–disease relationships can be challenging. Objective: We sought to expand the catalogue of monogenic etiologies for isolated dystonia. Methods: After the discovery of a candidate variant in a multicenter exome-sequenced cohort of affected individuals with dystonia, we queried online platforms and genomic data repositories worldwide to identify subjects with matching genotypic profiles. Results: Seven different biallelic loss-of-function variants in AOPEP were detected in five probands from four unrelated families with strongly overlapping phenotypes. In one proband, we observed a homozygous nonsense variant (c.1477C>T [p.Arg493*]). A second proband harbored compound heterozygous nonsense variants (c.763C>T [p.Arg255*]; c.777G>A [p.Trp259*]), whereas a third proband possessed a frameshift variant (c.696_697delAG [p.Ala234Serfs*5]) in trans with a splice-disrupting alteration (c.2041-1G>A). Two probands (siblings) from a fourth family shared compound heterozygous frameshift alleles (c.1215delT [p.Val406Cysfs*14]; c.1744delA [p.Met582Cysfs*6]). All variants were rare and expected to result in truncated proteins devoid of functionally important amino acid sequence. AOPEP, widely expressed in developing and adult human brain, encodes a zinc-dependent aminopeptidase, a member of a class of proteolytic enzymes implicated in synaptogenesis and neural maintenance. The probands presented with disabling progressive dystonia predominantly affecting upper and lower extremities, with variable involvement of craniocervical muscles. Dystonia was unaccompanied by any additional symptoms in three families, whereas the fourth family presented co-occurring late-onset parkinsonism. Conclusions: Our findings suggest a likely causative role of predicted inactivating biallelic AOPEP variants in cases of autosomal recessive dystonia. Additional studies are warranted to understand the pathophysiology associated with loss-of-function variation in AOPEP.
    • Blaubeuren, Cloppenburg, and Machtenstein—Three recently recognized H‐group chondrite finds in Germany with distinct terrestrial ages and weathering effects

      Bischoff, Addi; Storz, Jakob; Barrat, Jean‐Alix; Heinlein, Dieter; Jull, A. J. Timothy; Merchel, Silke; Pack, Andreas; Rugel, Georg; University of Arizona AMS Laboratory (Wiley, 2022-01-17)
      In the last 7 years, three meteorites (Blaubeuren, Cloppenburg, and Machtenstein) found in Germany were identified as chondrites. Two of these rocks had been recovered from the impact sites decades ago but were not considered to be meteorites. The aim of this study is to fully characterize these three meteorites. Based on the compositional data on the silicates, namely olivine and low-Ca pyroxene, these meteorites fit nicely within the H-group ordinary chondrites. The brecciated texture of Blaubeuren and Cloppenburg (both H4-5) is perfectly visible, whereas that of Machtenstein, officially classified as an H5 chondrite, is less obvious but was detected and described in this study. Considering chondrites in general, brecciated rocks are very common rather than an exception. The bulk rock degree of shock is S2 for Blaubeuren and Machtenstein and S3 for Cloppenburg. All samples show significant features of weathering. They have lost their original fusion crust and more than half (W3) or about half (W2-3) of their original metal abundances. The oxygen isotope compositions of the three chondrites are consistent with those of other H chondrites; however, the Cloppenburg values are heavily disturbed and influenced by terrestrial weathering. This is supported by the occurrence of the very rare hydrated iron phosphate mineral vivianite (Fe2+Fe2+2[PO4]2·8H2O), which indicates that the chondrite was weathered in a very wet environment. The terrestrial ages of Blaubeuren (~9.2 ka), Cloppenburg (~5.4 ka), and Machtenstein (~1.8 ka) show that these chondrites are very similar in their degree of alteration and terrestrial age compared to meteorite finds from relatively wet terrestrial environments. They still contain abundant metal, although, as noted, the oxygen isotope data indicate substantial weathering of Cloppenburg. The bulk compositions of the three meteorites are typical for H chondrites, although terrestrial alteration has slightly modified the concentrations, leading in general to a loss of Fe, Co, and Ni due to preferential alteration of metals and sulfides. As exceptions, Co and Ni concentrations in Machtenstein, which has the shortest terrestrial age, are typical for H chondrites. The chemical data show no enrichments in Ba and Sr, as is often observed in different meteorite groups of desert finds.
    • 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.
    • Cardiovascular reactivity, stress, and personal emotional salience: Choose your tasks carefully

      Bourassa, Kyle J.; Sbarra, David A.; Department of Psychology, University of Arizona (Wiley, 2022-03-15)
      Both greater cardiovascular reactivity and lesser reactivity (“blunting”) to laboratory stressors are linked to poor health outcomes, including among people who have a history of traumatic experiences. In a sample of recently separated and divorced adults (N = 96), this study examined whether differences in cardiovascular reactivity might be explained by differences in the personal emotional salience of the tasks and trauma history. Participants were assessed for trauma history, current distress related to their marital dissolution, and cardiovascular reactivity during two tasks, a serial subtraction math stressor task and a divorce-recall task. Participants with a greater trauma history evidenced less blood pressure reactivity to the serial subtraction task (a low personal emotional salience task) when compared to participants with less trauma history. In contrast, participants with a greater trauma history evidenced higher blood pressure reactivity to the divorce-recall task, but only if they also reported more divorce-related distress (high personal emotional salience). These associations were not significant for heart rate reactivity. Among people with a history of more traumatic experiences, a task with low personal salience was associated with a lower blood pressure response, whereas a task with higher personal emotional salience was associated with a higher blood pressure response. Future studies examining cardiovascular reactivity would benefit from determining the personal emotional salience of tasks, particularly for groups that have experienced stressful life events or trauma.
    • The central nervous system of whip spiders (Amblypygi): large mushroom bodies receive olfactory and visual input

      Sinakevitch, Irina; Long, Skye; Gronenberg, Wulfila; Univ Arizona, Dept Neurosci; Univ Arizona, Evelyn F McKnight Brain Inst, Div Neural Syst Memory & Aging (Wiley, 2020-10)
      Whip spiders (Amblypygi) are known for their nocturnal navigational abilities, which rely on chemosensory and tactile cues and, to a lesser degree, on vision. Unlike true spiders, the first pair of legs in whip spiders is modified into extraordinarily long sensory organs (antenniform legs) covered with thousands of mechanosensory, olfactory and gustatory sensilla. Olfactory neurons send their axons through the leg nerve into the corresponding neuromere of the central nervous system, where they terminate on a particularly large number (about 460) of primary olfactory glomeruli, suggesting an advanced sense of smell. From the primary glomeruli, olfactory projection neurons ascend to the brain and terminate in the mushroom body calyx on a set of secondary olfactory glomeruli, a feature that is not known from olfactory pathways of other animals. Another part of the calyx receives visual input from the secondary visual neuropil (the medulla). This calyx region is composed of much smaller glomeruli (‘microglomeruli’). The bimodal input and the exceptional size of their mushroom bodies may support the navigational capabilities of whip spiders. In addition to input to the mushroom body, we describe other general anatomical features of the whip spiders’ central nervous system.
    • Changes in Deep Groundwater Flow Patterns Related to Oil and Gas Activities

      Jellicoe, Keegan; McIntosh, Jennifer C.; Ferguson, Grant; Hydrology and Atmospheric Sciences, University of Arizona (Wiley, 2021-09-24)
      Large volumes of saline formation water are both produced from and injected into sedimentary basins as a by-product of oil and gas production. Despite this, the location of production and injection wells has not been studied in detail at the regional scale and the effects on deep groundwater flow patterns (i.e., below the base of groundwater protection) possibly driving fluid flow toward shallow aquifers remain uncertain. Even where injection and production volumes are equal at the basin scale, local changes in hydraulic head can occur due to the distribution of production and injection wells. In the Canadian portion of the Williston Basin, over 4.6 × 109 m3 of water has been co-produced with 5.4 × 108 m3 of oil, and over 5.5 × 109 m3 of water has been injected into the subsurface for salt water disposal or enhanced oil recovery. Despite approximately equal values of produced and injected fluids at the sedimentary basin scale over the history of development, cumulative fluid deficits and surpluses per unit area in excess of a few 100 mm are present at scales of a few 100 km2. Fluid fluxes associated with oil and gas activities since 1950 likely exceed background groundwater fluxes in these areas. Modeled pressures capable of creating upward hydraulic gradients are predicted for the Midale Member and Mannville Group, two of the strata with the highest amounts of injection in the study area. This could lead to upward leakage of fluids if permeable pathways, such as leaky wells, are present. © 2021 National Ground Water Association.
    • The changing role of history in restoration ecology

      Higgs, Eric; Falk, Donald A; Guerrini, Anita; Hall, Marcus; Harris, Jim; Hobbs, Richard J; Jackson, Stephen T; Rhemtulla, Jeanine M; Throop, William; School of Natural Resources and the Environment, University of Arizona (Wiley, 2014-11)
      In the face of rapid environmental and cultural change, orthodox concepts in restoration ecology such as historical fidelity are being challenged. Here we re-examine the diverse roles played by historical knowledge in restoration, and argue that these roles remain vitally important. As such, historical knowledge will be critical in shaping restoration ecology in the future. Perhaps the most crucial role in shifting from the present version of restoration ecology (“v1.0”) to a newer formulation (“v2.0”) is the value of historical knowledge in guiding scientific interpretation, recognizing key ecological legacies, and influencing the choices available to practitioners of ecosystem intervention under conditions of open-ended and rapid change.
    • Chloroplast quality control pathways are dependent on plastid DNA synthesis and nucleotides provided by cytidine triphosphate synthase two

      Alamdari, Kamran; Fisher, Karen E.; Tano, David W.; Rai, Snigdha; Palos, Kyle; Nelson, Andrew D. L.; Woodson, Jesse D.; The School of Plant Sciences, University of Arizona (Wiley, 2021-06-21)
      Reactive oxygen species (ROS) produced in chloroplasts cause oxidative damage, but also signal to initiate chloroplast quality control pathways, cell death, and gene expression. The Arabidopsis thaliana plastid ferrochelatase two (fc2) mutant produces the ROS singlet oxygen in chloroplasts that activates such signaling pathways, but the mechanisms are largely unknown. Here we characterize one fc2 suppressor mutation and map it to CYTIDINE TRIPHOSPHATE SYNTHASE TWO (CTPS2), which encodes one of five enzymes in Arabidopsis necessary for de novo cytoplasmic CTP (and dCTP) synthesis. The ctps2 mutation reduces chloroplast transcripts and DNA content without similarly affecting mitochondria. Chloroplast nucleic acid content and singlet oxygen signaling are restored by exogenous feeding of the dCTP precursor deoxycytidine, suggesting ctps2 blocks signaling by limiting nucleotides for chloroplast genome maintenance. An investigation of CTPS orthologs in Brassicaceae showed CTPS2 is a member of an ancient lineage distinct from CTPS3. Complementation studies confirmed this analysis; CTPS3 was unable to compensate for CTPS2 function in providing nucleotides for chloroplast DNA and signaling. Our studies link cytoplasmic nucleotide metabolism with chloroplast quality control pathways. Such a connection is achieved by a conserved clade of CTPS enzymes that provide nucleotides for chloroplast function, thereby allowing stress signaling to occur. © 2021 The Authors New Phytologist © 2021 New Phytologist Foundation