• Highly Dy2O3 and Er2O3 doped boron-aluminosilicate glasses for magneto-optical devices operating at 2 µm

      Dubrovin, V.D.; Zhu, X.; Mollaee, M.; Zong, J.; Peyghambarian, N.; James C. Wyant College of Optical Sciences, The University of Arizona (Elsevier BV, 2021-10)
      Magneto-optical glass materials with large Verdet constants at 2 μm have attracted increasing attention due to the significant advances of novel lasers operating at this wavelength region. In this paper, 13Al2O3-21B2O3-35.4SiO2-(30.6-X)Er2O3-XDy2O3 glasses have been synthesized, and their physical, optical, and magneto-optical properties were studied for making Faraday devices at 2 μm. A Verdet constant of as high as −5.9 rad/(T*m) at 1950 nm was measured with a 13Al2O3-21B2O3-35.4SiO2-30.6Dy2O3 glass. The temperature difference between crystallization and glass transition of 150 °C and the synthesis temperature of below 1500 °С make this glass very promising for making magneto-optical devices for 2 μm applications.
    • Phytoextraction efficiency of Arabidopsis halleri is driven by the plant and not by soil metal concentration

      Dietrich, Charlotte C.; Tandy, Susan; Murawska-Wlodarczyk, Kamila; Banaś, Angelika; Korzeniak, Urszula; Seget, Barbara; Babst-Kostecka, Alicja; Department of Environmental Science, The University of Arizona (Elsevier BV, 2021-12)
      The hyperaccumulation trait allows some plant species to allocate remarkable amounts of trace metal elements (TME) to their foliage without suffering from toxicity. Utilizing hyperaccumulating plants to remediate TME contaminated sites could provide a sustainable alternative to industrial approaches. A major hurdle that currently hampers this approach is the complexity of the plant-soil relationship. To better anticipate the outcome of future phytoremediation efforts, we evaluated the potential for soil metal-bioavailability to predict TME accumulation in two non-metallicolous and two metallicolous populations of the Zn/Cd hyperaccumulator Arabidopsis halleri. We also examined the relationship between a population's habitat and its phytoextraction efficiency. Total Zn and Cd concentrations were quantified in soil and plant material, and bioavailable fractions in soil were quantified via Diffusive Gradients in Thin-films (DGT). We found that shoot TME accumulation varied independent from both total and bioavailable soil TME concentrations in metallicolous individuals. In fact, hyperaccumulation patterns appear more plant- and less soil-driven: one non-metallicolous population proved to be as efficient in accumulating Zn on non-polluted soil as the metallicolous populations in their highly contaminated environment. Our findings demonstrate that in-situ information on plant phytoextraction efficiency is indispensable to optimize site-specific phytoremediation measures. If successful, hyperaccumulating plant biomass may provide valuable source material for application in the emerging field of green chemistry. © 2021 Elsevier Ltd
    • Designing additively manufactured lattice structures based on deformation mechanisms

      Babamiri, Behzad Bahrami; Barnes, Baxter; Soltani-Tehrani, Arash; Shamsaei, Nima; Hazeli, Kavan; Aerospace and Mechanical Engineering Department, The University of Arizona (Elsevier BV, 2021-10)
      The post-yield mechanical behavior of additively manufactured lattice structures (AMLS) is governed by the interplay between intrinsic (microstructural) and extrinsic (structural topology) properties at different length scales. Herein, we introduce a novel design optimization approach that accounts for scale separation and size effects, which control deformation mechanisms, to achieve a certain targeted macroscopic mechanical response. The new topological designs are guided by finding a direct correlation between the distribution of local stresses within struts and the underlying microstructures. The local stresses are computed using a strut-level yield criterion that has been calibrated to strut-level tensile, compressive, and shear loading experiments. Therefore, the local response of the struts, including tension-compression asymmetry, build direction dependence, and size effects, are accounted for in the yield surface, enabling a more accurate representation of the local stress state. Accurate calculation of the stress state for a given microstructure and topology combination allows for optimizing the topology for the given strut-level microstructure. The interplay between the topology and microstructure is assessed by investigating the unit cell-level deformation mechanisms and quantifying their influence on the global stress-strain relationship via finite element simulations. Using these relationships, a new set of topologies is designed, built, and validated with experiments. On average, the new topologies demonstrate 40% and 72% improvement in energy absorption capacity and flow stress, respectively, compared to topologies that had been previously optimized using constitutive models, which are homogeneous throughout the unit cell. The goal of the presented article is to demonstrate that simultaneously considering the effects of topology and microstructure on the mechanical behavior of AMLS has the potential to substantially improve key performance metrics, including ultimate strength and energy dissipation. The distinguishing and novel feature of our approach is that the topological optimization is performed while accounting for the heterogeneous distribution of strut-level microstructural features and concomitant mechanical behavior, which leads to new insights relative to peak AMLS structural performance.
    • Hyperspectral remote sensing for detecting geotechnical problems at ray mine

      He, Jingping; Barton, Isabel; Department of Mining and Geological Engineering, University of Arizona (Elsevier BV, 2021-10)
      While many or most geotechnical problems at open-pit mines are related to geological structures or discontinuities, highwall movement and failure can also occur as a consequence of nonstructural geological factors. Nonstructural causes of movement are not amenable to detection by conventional geotechnical sensing techniques such as LiDAR. In this case study, we applied hyperspectral remote sensing for large-scale mapping and detection of minerals at a non-structure-related ground instability in the highwalls of the Ray mine near Tucson, Arizona. The spectral images, obtained and integrated with radar images and the geological map, show that the dominant spectrally active mineral underlying the unstable area is the swelling clay montmorillonite, whereas kaolinite and white mica are more common in more stable parts of the highwall. The montmorillonite is concentrated in an outcropping altered diabase and conglomerate that underlie more competent rocks, providing a potential lift and slip surface. This study shows that hyperspectral remote sensing can aid in geotechnical slope characterization, particularly for nonstructural causes of failure. We provide a brief overview of best practices for hyperspectral remote sensing in geotechnical applications (combining drone- and tripod-mounted sensors, integrating hyperspectral with LiDAR and radar data, and using an iteratively refined spectral library based on site-specific sampling supported by ground truth).
    • Geodetic Extension Across the Southern Basin and Range and Colorado Plateau

      Broermann, J.; Bennett, R.A.; Kreemer, C.; Blewitt, G.; Pearthree, P.A.; Department of Geosciences, University of Arizona; Arizona Geological Survey, University of Arizona (Blackwell Publishing Ltd, 2021)
      Rates of crustal deformation in the southern Basin and Range (SBR) and Colorado Plateau (CP) provinces are relatively low in the context of the Pacific-North America plate boundary (PA–NA); however, the accumulation of small amounts of strain over long periods of time can lead to large earthquakes such as the Mw 7.5 1887 Sonoran earthquake in northern Mexico. SBR and CP rates of deformation are difficult to quantify due to a dearth of young faulting and seismicity. Moreover, strain accumulation and release related to the adjacent, more active San Andreas and Gulf of California fault systems to the west and southwest can mask the background strain rates associated with SBR and CP tectonics. With data from an enhanced continuous GPS network, we estimate crustal surface velocities of the SBR and CP, after removing coseismic and postseismic displacements, and elastic loading effects arising from major fault zones to the (south)west. We use cluster analysis and geologic data to separate the GPS velocity field into regions and calculate distinct block rotation and uniform strain rates for each region. We find the highest strain rate region includes southwestern Arizona; an area with sparse Quaternary faults, relatively low seismicity, and a relatively large discrepancy between geodetic and geologic rates of deformation. This anomalous strain rate may reflect residual, unmodeled PA-NA strain seeping into the Arizona study area from the west. Alternatively, it may represent the potential for one or more rare, future, large-magnitude earthquakes or indicate strain is being released through other process(es). © 2021. American Geophysical Union. All Rights Reserved.
    • The origin of imported jars from 6th dynasty abusir: New light on early bronze age egyptian-levantine relations

      Sowada, K.; Ownby, M.; Bárta, M.; University of Arizona (University of Chicago Press, 2021)
      Thin-section petrography on imported Combed jars from the 6th Dynasty Abusir tomb complex of Qar and his family identified the central Levant, between Beirut and Tripoli, as the production zone of the vessels. Dating to the reign of 6th Dynasty king Pepy II (ca. 2278–2184 B.C.), the jars were made of the same mixed Cretaceous clay type used for imports of the early Old Kingdom. None of the Abusir material was an Egyptian imitation, contrary to previous assessments. The petrography demonstrates the long continuity of exchange networks with a specific area of the central Levant for over 350 years. During the Old Kingdom from the early 4th Dynasty to the late 6th Dynasty, exchange networks with the region intensified, confirming long-held understandings based on fragmentary archaeological data and the slender textual record. © 2021 American Schools of Overseas Research. All rights reserved.
    • Energy feedthrough and microstructure evolution during direct laser peening of aluminum in femtosecond and picosecond regimes

      Nakhoul, A.; Rudenko, A.; Sedao, X.; Peillon, N.; Colombier, J.P.; Maurice, C.; Blanc, G.; Borbély, A.; Faure, N.; Kermouche, G.; et al. (American Institute of Physics Inc., 2021)
      Ultrafast laser was recently used to modify the surface integrity and peen the surface region of aluminum based alloy 2024-T351 without a sacrificial layer prior to the process. We show that controllable laser parameters such as fluence and pulse duration have a significant influence on peening qualities, such as the compressive residual stress, hardness, and surface roughness of peened parts. The residual stress profile was analyzed by x-ray diffraction. By controlling the laser fluence and pulse duration, it was possible to obtain 200 MPa of compressive residual stresses close to the surface and 100 MPa of compressive residual stresses at 50 μm depth. Moreover, micro-hardness was increased from 2.1 to 2.5 GPa in the near-surface region. In addition, the dislocation densities were evaluated from high-resolution x-ray diffraction peaks. The increase of the dislocation density indicates that plastic deformation occurred, which generated compressive residual stresses and hardness enhancement. Plastic deformation is considered to be created by an ultrafast laser-induced pressure wave. The correlation between laser parameters and modified surface properties is interpreted by the complex interplay between laser excitation, material relaxation, and pressure waves. A pulse duration in the picosecond range and a relatively low fluence is possibly the optimal condition for a best peening quality with small surface roughness, which could potentially be used to reduce surface cracking and associated failures of additively manufactured parts. © 2021 Author(s).
    • Marshallsussmanite, NaCaMnSi 3 O 8 (OH), a new pectolite-group mineral providing insight into hydrogen bonding in pyroxenoids

      Origlieri, M.J.; Downs, R.T.; Hoffman, D.R.; Ducea, M.N.; Post, J.E.; Department of Geosciences, University of Arizona (Cambridge University Press, 2021)
      Marshallsussmanite (IMA2013-067) is a new pyroxenoid mineral from the Wessels mine, Kalahari Manganese Field, Northern Cape Province, South Africa. Marshallsussmanite has ideal formula NaCaMnSi3O8(OH) and triclinic P symmetry. Marshallsussmanite forms vitreous pink bladed crystals to 2.1 cm. The mineral shows perfect cleavage on both {100} and {001}. The chemical composition from electron microprobe (average of 20 analyses) and inductively coupled plasma mass spectrometer analysis (average of three analyses) is Li2O 0.43, Na2O 8.06, MgO 0.08, CaO 15.33, MnO 21.79, SiO2 51.71; totalling 97.40 wt.%. The empirical formula, normalized to 3 Si and assuming 1 H apfu is Li0.100Na0.906Ca0.953Mg0.007Mn1.071Si3O8(OH). Unit-cell parameters from single crystal X-ray diffraction are a = 7.7854(4), b = 6.9374(4), c = 6.8516(3) Å, α = 90.683(3)°, β = 94.330(3)°, γ = 102.856(3)°, V = 359.59(3) Å3; Z = 2. The crystal structure refinement converged with Robs = 0.0248 and site occupancy refinement gives crystal chemistry [Na0.948Li0.052][Ca0.793Mn0.207] [Mn0.937Ca0.063]Si3O8(OH). Marshallsussmanite is a single chain silicate with a repeat interval of three tetrahedra (i.e. dreier chain). Marshallsussmanite is a member of the pectolite group of pyroxenoids, which also includes barrydawsonite-(Y), cascandite, pectolite, serandite and tanohataite. Parallel silicate chains form layers, intercalated with well-ordered cation layers. Calcium and Mn both exhibit octahedral coordination, while Na has four bonded interactions in a coordination sphere (radius 3 Å) of seven separate O atoms. Procrystal electron density and bond valence modelling results are compared. The mineral has an unusually strong hydrogen bond with O4O3 separation of 2.458(2) Å. Unlike pectolite and serandite, O4 in marshallsussmanite acts as an H-bond donor and O3 is an H-bond acceptor. Cation ordering in pyroxenoids has a substantial impact on the H position and corresponding H-bonding schemata. Copyright © The Author(s), 2018. Published by Cambridge University Press on behalf of The Mineralogical Society of Great Britain and Ireland.
    • Determination of aquaponic water macronutrient concentrations based on lactuca sativa leaf photosynthetic signatures using hybrid gravitational search and recurrent neural network

      Concepcion, R., II; Dadios, E.; Cuello, J.; Bandala, A.; Sybingco, E.; Vicerra, R.R.; Department of Agricultural and Biosystems Engineering, University of Arizona (Walailak University, 2021)
      Crop quality depends dominantly on the nutrients present in its growth media. For precision farming, fertigation is a challenge, especially when dealing with economical and efficiency factors. In this study, the aquaponic pond water macronutrient prediction model (wNPK) was developed based on leaf photosynthetic signature predictors. Aquaphotomics was preliminarily used for correlating physical limnological properties with nitrate, phosphate, potassium concentrations, and the leaf signatures. Using a digital camera, 18 spectro-textural-morphological features were extracted. Neighborhood component analysis (NCA) and ReliefF algorithms selected the spectral components blue, a*, and red minus luma as the most significant as supported by principal component analysis, resulting in low computational cost. A Gravitational Search Algorithm (GSA) was employed to optimize the recurrent neural network (RNN) architecture resulting in higher sensitivity. The hybrid NCA-ReliefF-GSA-RNN (wNPK) predicted NPK with 93.61, 84.03, and 91.39 % accuracy, respectively, besting out other configured feature-based machine learning models. Using wNPK, it was confirmed that potassium helped in accelerating seed germination and nitrogen in promoting chlorophyll intensification, especially on the 6th week after sowing. Phosphate and potassium were the energy and health elements that were consumed in a larger amount at the end of the head development stage. wNPK rules out that macronutrient concentration have a direct resemblance to crop leaf signatures; thus, a leaf is a good indicator of the water quality. The results pointed out that the use of a single camera to measure both water macronutrient concentrations and crop signature at the same time is an innovative, efficient, and economical approach for precision farming.
    • Pancreatic Islets Exhibit Dysregulated Adaptation of Insulin Secretion after Chronic Epinephrine Exposure

      Li, R.; Huang, H.; Limesand, S.W.; Chen, X.; School of Animal and Comparative Biomedical Sciences, University of Arizona (MDPI, 2021)
      Chronic adrenergic stimulation is the dominant factor in impairment of the β-cell function. Sustained adrenergic exposure generates dysregulated insulin secretion in fetal sheep. Similar results have been shown in Min6 under the elevated epinephrine condition, but impairments after adrenergic removal are still unknown and a high rate of proliferation in Min6 has been ignored. Therefore, we incubated primary rats' islets with half maximal inhibitory concentrations of epinephrine for three days, then determined their insulin secretion responsiveness and related signals two days after removal of adrenaline via radioimmunoassay and qPCR. Insulin secretion was not different between the exposure group (1.07 ± 0.04 ng/islet/h) and control (1.23 ± 0.17 ng/islet/h), but total islet insulin content after treatment (5.46 ± 0.87 ng/islet/h) was higher than control (3.17 ± 0.22 ng/islet/h, p < 0.05), and the fractional insulin release was 36% (p < 0.05) lower after the treatment. Meanwhile, the mRNA expression of Gαs, Gαz and Gβ1-2 decreased by 42.8% 19.4% and 24.8%, respectively (p < 0.05). Uncoupling protein 2 (Ucp2), sulphonylurea receptor 1 (Sur1) and superoxide dismutase 2 (Sod2) were significantly reduced (38.5%, 23.8% and 53.8%, p < 0.05). Chronic adrenergic exposure could impair insulin responsiveness in primary pancreatic islets. Decreased G proteins and Sur1 expression affect the regulation of insulin secretion. In conclusion, the sustained under-expression of Ucp2 and Sod2 may further change the function of β-cell, which helps to understand the long-term adrenergic adaptation of pancreatic β-cell.
    • Global analysis of rna-dependent rna polymerase-dependent small rnas reveals new substrates and functions for these proteins and sgs3 in arabidopsis

      Hua, X.; Berkowitz, N.D.; Willmann, M.R.; Yu, X.; Lyons, E.; Gregory, B.D.; School of Plant Sciences, University of Arizona; CyVerse, University of Arizona (MDPI AG, 2021)
      RNA silencing pathways control eukaryotic gene expression transcriptionally or posttran-scriptionally in a sequence-specific manner. In RNA silencing, the production of double-stranded RNA (dsRNA) gives rise to various classes of 20–24 nucleotide (nt) small RNAs (smRNAs). In Arabidopsis thaliana, smRNAs are often derived from long dsRNA molecules synthesized by one of the six genomically encoded RNA-dependent RNA Polymerase (RDR) proteins. However, the full complement of the RDR-dependent smRNAs and functions that these proteins and their RNA-binding cofactors play in plant RNA silencing has not been fully uncovered. To address this gap, we performed a global genomic analysis of all six RDRs and two of their cofactors to find new substrates for RDRs and targets of the resulting RDR-derived siRNAs to uncover new functions for these proteins in plants. Based on these analyses, we identified substrates for the three RDRγ clade proteins (RDR3–5), which had not been well-characterized previously. We also identified new substrates for the other three RDRs (RDR1, RDR2, and RDR6) as well as the RDR2 cofactor RNA-directed DNA methylation 12 (RDM12) and the RDR6 cofactor suppressor of gene silencing 3 (SGS3). These findings revealed that the target substrates of SGS3 are not limited to those solely utilized by RDR6, but that this protein seems to be a more general cofactor for the RDR family of proteins. Additionally, we found that RDR6 and SGS3 are involved in the production of smRNAs that target transcripts related to abiotic stresses, including water deprivation, salt stress, and ABA response, and as expected the levels of these mRNAs are increased in rdr6 and sgs3 mutant plants. Correspondingly, plants that lack these proteins (rdr6 and sgs3 mutants) are hypersensitive to ABA treatment, tolerant to high levels of PEG8000, and have a higher survival rate under salt treatment in comparison to wild-type plants. In total, our analyses have provided an extremely data-rich resource for uncovering new functions of RDR-dependent RNA silencing in plants, while also revealing a previously unexplored link between the RDR6/SGS3-dependent pathway and plant abiotic stress responses. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
    • Parity and later life risk for coronary heart disease among slum-dwelling women in Mysore, India

      Krupp, K.; Pope, B.; Srinivas, A.; Ravi, K.; Khan, A.; Srinivas, V.; Madhivanan, P.; Bastida, E.; Department of Health Promotion Sciences, Mel & Enid Zuckerman College of Public Health, University of Arizona (Elsevier B.V., 2021)
      Background: To examine the role of parity in coronary heart disease (CHD) among middle-aged Indian women living in government-designated slums in Mysore, India. Methods: Between October 2017 and May 2018, a cross-sectional study was carried out among women, 40–64 years of age, residing in government-designated slums in Mysore, India. In addition to socio-demographics, data were collected on CVD risk factors including use of tobacco and alcohol, diet, physical activity, sleep, quality of life, and personal and family history of chronic disease. Patients underwent a medical examination and a venous blood sample was taken for fasting lipid measurement. Resting electrocardiography was carried out by a trained medical technician. Multivariable logistic regression with associated 95% confidence intervals was used to examine the relationship between parity and coronary heart disease. Results: The prevalence of CHD in this sample of middle-aged women was 6.4%. Nulliparous women were at heightened risk for CHD compared to parous women with up to five live births. In the adjusted model, women who had 1-2 and 3–5 live births had 0.24 times lower odds (95% Confidence Interval [CI]: 0.05–1.29) and 0.38 times lower odds (95%CI: 0.178–0.87) of CHD, respectively, as compared to nulliparous women. Conclusion: Among a fairly homogenous population of slum-dwelling women reporting almost universal breastfeeding for three or more months following birth, parity up to five births appeared protective against CHD. Further studies are needed to evaluate whether near universal breastfeeding rates in this population mediated the relationship of parity and CHD. © 2021 Cardiological Society of India
    • Longitudinal imaging-based clusters in former smokers of the copd cohort associate with clinical characteristics: The subpopulations and intermediate outcome measures in copd study (spiromics)

      Zou, C.; Li, F.; Choi, J.; Haghighi, B.; Choi, S.; Rajaraman, P.K.; Comellas, A.P.; Newell, J.D.; Jnr; Lee, C.H.; et al. (Dove Medical Press Ltd, 2021)
      Purpose: Quantitative computed tomography (qCT) imaging-based cluster analysis identified clinically meaningful COPD former-smoker subgroups (clusters) based on cross-sectional data. We aimed to identify progression clusters for former smokers using longitudinal data. Patients and Methods: We selected 472 former smokers from SPIROMICS with a baseline visit and a one-year follow-up visit. A total of 150 qCT imaging-based variables, comprising 75 variables at baseline and their corresponding progression rates, were derived from the respective inspiration and expiration scans of the two visits. The COPD progression clusters identified were then associated with subject demography, clinical variables and biomarkers. Results: COPD severities at baseline increased with increasing cluster number. Cluster 1 patients were an obese subgroup with rapid progression of functional small airway disease percentage (fSAD%) and emphysema percentage (Emph%). Cluster 2 exhibited a decrease of fSAD% and Emph%, an increase of tissue fraction at total lung capacity and airway narrowing over one year. Cluster 3 showed rapid expansion of Emph% and an attenuation of fSAD%. Cluster 4 demonstrated severe emphysema and fSAD and significant structural alterations at baseline with rapid progression of fSAD% over one year. Subjects with different progression patterns in the same cross-sectional cluster were identified by longitudinal clustering. Conclusion: qCT imaging-based metrics at two visits for former smokers allow for the derivation of four statistically stable clusters associated with unique progression patterns and clinical characteristics. Use of baseline variables and their progression rates enables identification of longitudinal clusters, resulting in a refinement of cross-sectional clusters. © 2021 Zou et al.
    • Performance of a handheld chlorophyll-a fluorometer: Potential use for rapid algae monitoring

      Hamdhani, H.; Eppehimer, D.E.; Walker, D.; Bogan, M.T.; School of Natural Resources and the Environment, University of Arizona; School of Natural Resources and the Environment, University of Arizona; Department of Environmental Science, University of Arizona (MDPI AG, 2021)
      Chlorophyll-a measurements are an important factor in the water quality monitoring of surface waters, especially for determining the trophic status and ecosystem management. However, a collection of field samples for extractive analysis in a laboratory may not fully represent the field conditions. Handheld fluorometers that can measure chlorophyll-a in situ are available, but their performance in waters with a variety of potential light-interfering substances has not yet been tested. We tested a handheld fluorometer for sensitivity to ambient light and turbidity and compared these findings with EPA Method 445.0 using water samples obtained from two urban lakes in Tucson, Arizona, USA. Our results suggested that the probe was not sensitive to ambient light and performed well at low chlorophyll-a concentrations (<25 µg/L) across a range of turbidity levels (50–70 NTU). However, the performance was lower when the chlorophyll-a concentrations were >25 µg/L and turbidity levels were <50 NTU. To account for this discrepancy, we developed a calibration equation to use for this handheld fluorometer when field monitoring for potential harmful algal blooms in water bodies. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
    • Moment analysis for modeling soil water distribution in furrow irrigation: Variable vs. constant ponding depths

      Kazemi, H.; Sadraddini, A.A.; Nazemi, A.H.; Sanchez, C.A.; Department of Soil, Water, and Environmental Sciences, College of Agriculture and Life Sciences, The University of Arizona (MDPI AG, 2021)
      Despite increasing use of pressurized irrigation methods, most irrigation projects world-wide still involve surface systems. Accurate estimation of the amount of infiltrating water and its spatial distribution in the soil is of great importance in the design and management of furrow irrigation systems. Moment analysis has previously been applied to describe the subsurface water distribution using input data from numerical simulations rather than field measured data, and as-suming a constant ponding depth in the furrow. A field experiment was conducted in a blocked-end level furrow at Maricopa Agricultural Center, Arizona, USA, to study the effect of time-variable ponding depths on soil water distribution and the resulting wetting bulb under real conditions in the field using moment analysis. The simulated volumetric soil water contents run with variable and constant (average) ponding depths using HYDRUS 2D/3D were almost identical, and both compared favorably with the field data. Hence, only the simulated soil water contents with variable ponding depths were used to calculate the moments. It was concluded that the fluctuating flow depth had no significant influence on the resulting time-evolving ellipses. This was related to the negligible 10-cm variation in ponding depths compared to the high negative matric potential of the unsaturated soil. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
    • Evaluation of tobacco screening and counseling in a large, midwestern pediatric emergency department

      Merianos, A.L.; Gordon, J.S.; Lyons, M.S.; Jandarov, R.A.; Mahabee-Gittens, E.M.; College of Nursing, The University of Arizona (European Publishing, 2021)
      INTRODUCTION The study objective was to assess tobacco screening and cessation counseling practices of pediatric emergency department (PED) and urgent care (UC) nurses and physicians, and factors associated with these practices. Secondarily, we assessed factors associated with performing tobacco smoke exposure reduction and tobacco cessation counseling. METHODS We conducted a cross-sectional survey of 30 PED/UC nurses and physicians working at one large, urban, Midwestern children’s hospital. Measures included current practices of performing the 5 As of tobacco counseling (Ask, Advise, Assess, Assist, Arrange), and attitude and practice factors that may influence practices. RESULTS Overall, 90.0% of participants had not received recent tobacco counseling training, 73.3% were unaware of the 5 As, and 63.3% did not have a standardized, routine screening system to identify patients exposed to secondhand smoke. The majority of participants reported that they: asked about patients’ secondhand smoke exposure status (70.0%) and parents’ tobacco use status (53.3%), and advised parental smokers to not smoke around their child (70.0%) and to quit smoking (50%). One in five participants reported they assessed smokers’ interest in quitting smoking, and 16.7% talked with smokers about cessation techniques and tactics; of these, 10% referred/enrolled smokers to the Tobacco Quitline or cessation program, and 6.7% made a quit plan or recommended nicotine replacement therapy medication. CONCLUSIONS Key findings identified are the need for professional tobacco counseling training, standardizing efforts during visits, and emphasizing pediatric patients’ potential health benefits. This information will be used for developing a PED/ UC-based parental tobacco cessation and child tobacco smoke exposure reduction intervention. © 2021. Merianos A. L. et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution NonCommercial 4.0 International License. (http://creativecommons.org/licenses/by-nc/4.0)
    • Using global Bayesian optimization in ensemble data assimilation: parameter estimation, tuning localization and inflation, or all of the above

      Lunderman, S.; Morzfeld, M.; Posselt, D.J.; Department of Mathematics, University of Arizona (Taylor and Francis Ltd., 2021)
      Global Bayesian optimization (GBO) is a derivative-free optimization method that is used widely in the tech-industry to optimize objective functions that are expensive to evaluate, numerically or otherwise. We discuss the use of GBO in ensemble data assimilation (DA), where the goal is to update the state of a numerical model in view of noisy observations. Specifically, we consider three tasks: (i) the estimation of model parameters; (ii) the tuning of localization and inflation in ensemble DA; (iii) doing both, i.e. estimating model parameters while simultaneously tuning the localization and inflation of the ensemble DA. For all three tasks, the GBO works ‘offline’, i.e. a set of ‘training’ observations are used within GBO to determine appropriate model or localization/inflation parameters, which are subsequently deployed within an ensemble DA system. Because of the offline nature of the technique, GBO can easily be combined with existing DA systems and it can effectively decouple (nearly) linear/Gaussian aspects of a problem from highly nonlinear/non-Gaussian ones. We illustrate the use of GBO in simple numerical experiments with the classical Lorenz problems. Our main goals are to introduce GBO in the context of ensemble DA and to spark an interest in GBO and its uses for streamlining important tasks in ensemble DA. © Tellus A: 2021. © 2021 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.
    • The Power of Schadenfreude: Predicting Behaviors and Perceptions of Trolling Among Reddit Users

      Brubaker, P.J.; Montez, D.; Church, S.H.; University of Arizona (SAGE Publications Ltd, 2021)
      Trolling is an uncivil behavior that is increasingly prevalent in online social interactions. This study sought to understand trolling by examining the psychological predictors that motivate trolling behaviors, as well as perceptions of trolling among 438 Reddit users. A path analysis indicated the motivation of schadenfreude mediates the relationship between personality traits (i.e., the dark triad) and trolling. Outspokenness neither directly nor indirectly predicted trolling. Results also showed that Reddit users motivated by schadenfreude and users who exhibit trolling behaviors view trolling as not being a dysfunctional or undesirable response to online discourse. In addition, those with schadenfreude considered the practice of trolling to be functional/comprehensible. Those who merely observe trolling on Reddit did not consider trolling to be a functional part of online discourse. Age, time spent on Reddit, and the dark triad did not predict functional or dysfunctional perceptions of trolling, but gender played a role. © The Author(s) 2021.
    • An alternative domain-swapped structure of the Pyrococcus horikoshii PolII mini-intein

      Williams, J.E.; Jaramillo, M.V.; Li, Z.; Zhao, J.; Wang, C.; Li, H.; Mills, K.V.; Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona (Nature Research, 2021)
      Protein splicing is a post-translational process by which an intein catalyzes its own excision from flanking polypeptides, or exteins, concomitant with extein ligation. Many inteins have nested homing endonuclease domains that facilitate their propagation into intein-less alleles, whereas other inteins lack the homing endonuclease (HEN) and are called mini-inteins. The mini-intein that interrupts the DNA PolII of Pyrococcus horikoshii has a linker region in place of the HEN domain that is shorter than the linker in a closely related intein from Pyrococcus abyssi. The P. horikoshii PolII intein requires a higher temperature for catalytic activity and is more stable to digestion by the thermostable protease thermolysin, suggesting that it is more rigid than the P. abyssi intein. We solved a crystal structure of the intein precursor that revealed a domain-swapped dimer. Inteins found as domain swapped dimers have been shown to promote intein-mediated protein alternative splicing, but the solved P. horikoshii PolII intein structure has an active site unlikely to be catalytically competent. © 2021, The Author(s).
    • Menopause impacts human brain structure, connectivity, energy metabolism, and amyloid-beta deposition

      Mosconi, L.; Berti, V.; Dyke, J.; Schelbaum, E.; Jett, S.; Loughlin, L.; Jang, G.; Rahman, A.; Hristov, H.; Pahlajani, S.; et al. (Nature Research, 2021)
      All women undergo the menopause transition (MT), a neuro-endocrinological process that impacts aging trajectories of multiple organ systems including brain. The MT occurs over time and is characterized by clinically defined stages with specific neurological symptoms. Yet, little is known of how this process impacts the human brain. This multi-modality neuroimaging study indicates substantial differences in brain structure, connectivity, and energy metabolism across MT stages (pre-menopause, peri-menopause, and post-menopause). These effects involved brain regions subserving higher-order cognitive processes and were specific to menopausal endocrine aging rather than chronological aging, as determined by comparison to age-matched males. Brain biomarkers largely stabilized post-menopause, and gray matter volume (GMV) recovered in key brain regions for cognitive aging. Notably, GMV recovery and in vivo brain mitochondria ATP production correlated with preservation of cognitive performance post-menopause, suggesting adaptive compensatory processes. In parallel to the adaptive process, amyloid-β deposition was more pronounced in peri-menopausal and post-menopausal women carrying apolipoprotein E-4 (APOE-4) genotype, the major genetic risk factor for late-onset Alzheimer’s disease, relative to genotype-matched males. These data show that human menopause is a dynamic neurological transition that significantly impacts brain structure, connectivity, and metabolic profile during midlife endocrine aging of the female brain. © 2021, The Author(s).