• Social context-dependent singing alters molecular markers of synaptic plasticity signaling in finch basal ganglia Area X

      So, Lisa Y.; Miller, Julie E.; Univ Arizona, Dept Neurosci; Univ Arizona, Dept Speech Language & Hearing Sci (Elsevier BV, 2021-02)
      Vocal communication is a crucial skill required throughout life. However, there is a critical gap in our understanding of the underlying molecular brain mechanisms, thereby motivating our use of the zebra finch songbird model. Adult male zebra finches show differences in neural activity patterns in song-dedicated brain nuclei when they sing in two distinct social contexts: a male singing by himself (undirected, UD) and a male singing to a female (female-directed, FD). In our prior work, we showed that in song-dedicated basal ganglia Area X, protein levels of a N-methyl-D-aspartate receptor subtype 2B (NMDAR2B) increased with more UD song and decreased with more FD song. We hypothesized that molecules downstream of this receptor would show differential protein expression levels in Area X between UD and FD song. Specifically, we investigated calcium/calmodulin dependent protein kinase II beta (CaMKIIB), homer scaffold protein 1 (HOMER1), serine/threonine protein kinase (Akt), and mechanistic target of rapamycin kinase (mTOR) following singing and non-singing states in Area X. We show relationships between social context and protein levels. HOMER1 protein levels decreased with time spent singing FD song, and mTOR protein levels decreased with the amount of and time spent singing FD song. For both HOMER1 and mTOR, there were no differences with the amount of UD song. With time spent singing UD, CaMKIIB protein levels trended in a U-shaped curve whereas Akt protein levels trended down. Both molecules showed no change with FD song. Our results support differential involvement of molecules in synaptic plasticity pathways between UD and FD song behaviors.
    • Calculations and analysis of 55Mn nuclear quadrupole coupling for asymmetric top acyl methyl manganese pentacarbonyl

      Tanjaroon, Chakree; Mills, David D.; Jiménez Hoyos, Carlos A.; Kukolich, Stephen G.; Univ Arizona, Dept Chem & Biochem (ELSEVIER SCIENCE BV, 2021-01)
      Revised assignments of the measured transitions for the asymmetric top acyl isomers of methyl manganese pentacarbonyl are presented, along with a corresponding fit to determine rotational and quadrupole coupling constants. New assignments for measured transitions give a better fit to the spectrum and better agreement between experimental and calculated quadrupole coupling strengths. The best agreements were obtained for B3LYP and M11 DFT calculations with triple and quadruple-zeta basis sets. Experimental molecular parameters from the new analysis are: A = 840.0843(52), B = 774.2861(17), C = 625.6528(13). DJ = 0.000212(21). DJK = 0.00488(18), 1.5χaa = −46.96(11), 0.25(χbb - χcc) = -13.44(3) MHz.
    • Data-driven model reduction, Wiener projections, and the Koopman-Mori-Zwanzig formalism

      Lin, Kevin K.; Lu, Fei; Univ Arizona, Dept Math (Elsevier BV, 2021-01)
      Model reduction methods aim to describe complex dynamic phenomena using only relevant dynamical variables, decreasing computational cost, and potentially highlighting key dynamical mechanisms. In the absence of special dynamical features such as scale separation or symmetries, the time evolution of these variables typically exhibits memory effects. Recent work has found a variety of data-driven model reduction methods to be effective for representing such non-Markovian dynamics, but their scope and dynamical underpinning remain incompletely understood. Here, we study data-driven model reduction from a dynamical systems perspective. For both chaotic and randomly-forced systems, we show the problem can be naturally formulated within the framework of Koopman operators and the Mori-Zwanzig projection operator formalism. We give a heuristic derivation of a NARMAX (Nonlinear Auto-Regressive Moving Average with eXogenous input) model from an underlying dynamical model. The derivation is based on a simple construction we call Wiener projection, which links Mori-Zwanzig theory to both NARMAX and to classical Wiener filtering. We apply these ideas to the Kuramoto-Sivashinsky model of spatiotemporal chaos and a viscous Burgers equation with stochastic forcing.
    • Corporate digital responsibility

      Lobschat, Lara; Mueller, Benjamin; Eggers, Felix; Brandimarte, Laura; Diefenbach, Sarah; Kroschke, Mirja; Wirtz, Jochen; Univ Arizona, Eller Coll Management (Elsevier BV, 2021-01)
      We propose that digital technologies and related data become increasingly prevalent and that, consequently, ethical concerns arise. Looking at four principal stakeholders, we propose corporate digital responsibility (CDR) as a novel concept. We define CDR as the set of shared values and norms guiding an organization's operations with respect to four main processes related to digital technology and data. These processes are the creation of technology and data capture, operation and decision making, inspection and impact assessment, and refinement of technology and data. We expand our discussion by highlighting how to managerially effectuate CDR com-pliant behavior based on an organizational culture perspective. Our conceptualization unlocks future research opportunities, especially regarding pertinent antecedents and consequences. Managerially, we shed first light on how an organization's shared values and norms regarding CDR can get translated into actionable guidelines for users. This provides grounds for future discussions related to CDR readiness, implementation, and success.
    • Atomic Embeddability, Clustered Planarity, and Thickenability

      Fulek, Radoslav; Tóth, Csaba D.; Univ Arizona, Dept Comp Sci (Society for Industrial and Applied Mathematics, 2020-12-23)
      We study the atomic embeddability testing problem, which is a common generalization of clustered planarity (c-planarity, for short) and thickenability testing, and present a polynomial time algorithm for this problem, thereby giving the first polynomial time algorithm for c-planarity. C-planarity was introduced in 1995 by Feng, Cohen, and Eades as a variant of graph planarity, in which the vertex set of the input graph is endowed with a hierarchical clustering and we seek an embedding (crossing free drawing) of the graph in the plane that respects the clustering in a certain natural sense. Until now, it has been an open problem whether c-planarity can be tested efficiently, despite relentless efforts. The thickenability problem for simplicial complexes emerged in the topology of manifolds in the 1960s. A 2-dimensional simplicial complex is thickenable if it embeds in some orientable 3-dimensional manifold. Recently, Carmesin announced that thickenability can be tested in polynomial time. Our algorithm for atomic embeddability combines ideas from Carmesin's work with algorithmic tools previously developed for weak embeddability testing. We express our results purely in terms of graphs on surfaces, and rely on the machinery of topological graph theory. Finally we give a polynomial-time reduction from c-planarity to thickenability and show that a slight generalization of atomic embeddability to the setting in which clusters are toroidal graphs is NP-complete.
    • Defensive structures influence fighting outcomes

      Emberts, Zachary; Wiens, John J.; Univ Arizona, Dept Ecol & Evolutionary Biol (WILEY, 2020-12-16)
      In many animal species, individuals engage in fights with conspecifics over access to limited resources (e.g. mates, food, or shelter). Most theory about these intraspecific fights assumes that damage has an important role in determining the contest winner. Thus, defensive structures that reduce the amount of damage an individual accrues during intraspecific competition should provide a fighting advantage. Examples of such damage-reducing structures include the dermal shields of goats, the dorsal osteoderms of crocodiles, and the armoured telsons of mantis shrimps. Although numerous studies have identified these defensive structures, no study has investigated whether they influence the outcomes of intraspecific fights. Here we investigated whether inhibiting damage by enhancing an individual's armour influenced fighting behaviour and success in the giant mesquite bug, Thasus neocalifornicus (Insecta: Hemiptera: Coreidae). We found that experimentally manipulated individuals (i.e. those provided with additional armour) were 1.6 times more likely to win a fight when compared to the control. These results demonstrate that damage, and damage-reducing structures, can influence fighting success. The implications of these results are twofold. First, our results experimentally support a fundamental assumption of most theoretical fighting models: that damage is a fighting cost that can influence contest outcomes. Second, these results highlight the importance of an individual's defensive capacity, and why defence should not be ignored. A free Plain Language Summary can be found within the Supporting Information of this article.
    • Extracting Inter-Sentence Relations for Associating Biological Context with Events in Biomedical Texts

      Noriega-Atala, Enrique; Hein, Paul D; Thumsi, Shraddha S; Wong, Zechy; Wang, Xia; Hendryx, Sean M; Morrison, Clayton T; Univ Arizona, Sch Informat; Univ Arizona, Dept Comp Sci; Univ Arizona, Dept Linguist; et al. (IEEE COMPUTER SOC, 2020-12-08)
      We present an analysis of the problem of identifying biological context and associating it with biochemical events described in biomedical texts. This constitutes a non-trivial, inter-sentential relation extraction task. We focus on biological context as descriptions of the species, tissue type, and cell type that are associated with biochemical events. We present a new corpus of open access biomedical texts that have been annotated by biology subject matter experts to highlight context-event relations. Using this corpus, we evaluate several classifiers for context-event association along with a detailed analysis of the impact of a variety of linguistic features on classifier performance. We find that gradient tree boosting performs by far the best, achieving an F1 of 0.865 in a cross-validation study.
    • More than a decade in the making: A study of the implementation of India's Right to Information Act

      Relly, Jeannine E.; Rabbi, Md. Fazle; Sabharwal, Meghna; Pakanati, Rajdeep; Schwalbe, Ethan H.; Univ Arizona, Sch Journalism (PERGAMON-ELSEVIER SCIENCE LTD, 2020-12)
      India's progressive Right to Information Act (RTIA) is a global model. The RTIA was adopted a decade and a half ago to serve as a check on corruption and to advance democracy, citizen equity and public accountability. Little primary research has been conducted on the implementation of the RTIA. This research employs a socio-political and technocratic framework to study influences on RTIA implementation over time from the citizen requester 'demand-side' and the governmental 'supply-side' from an institutional development process perspective. Our constructivist approach utilizes in-depth semi-structured interviews from frequent information requesters and information commissioners (N = 114) and a new dataset of a random stratified sample of information commissioner decisions for release of information under the RTIA (N = 500). We found that political will, bureaucratic culture, and societal activism and engagement were the strongest overarching socio-political factors impacting implementation. Socio-political subfactors that appeared weak or wanting in the RTI regime were leadership, oversight, coordination, positive workplace incentives, reflexivity, and public information officer communication style with citizen requesters. Technocratic constraints, directly influenced by socio-political factors that impact implementation, included follow-through on administrative policies and rules, capacity building, monitoring, oversight, and sanctions. This study found that technocratic factors included in the institutional design of RTI legislation may not be sufficient for short-term institutional change in cultures of bureaucratic secrecy. However, coalitions of citizens, civil society organizations, media, engaged public officials, and interested politicians can drive a transparency agenda in a country when political will and bureaucratic leadership are weak. (C) 2020 Published by Elsevier Ltd.
    • Carbon photochemistry at Mars: Updates with recent data

      Lo, Daniel Y.; Yelle, Roger V.; Lillis, Robert J.; Univ Arizona, Lunar & Planetary Lab (Elsevier BV, 2020-12)
      We provide a comprehensive characterization of the photochemistry behind atomic carbon in the Mars atmosphere. Using a one-dimensional photochemical model, with an extensive reaction list incorporating new high-resolution photodissociation cross-sections (Heays et al., 2017) and the recently experimentally confirmed CO2 + h nu -> C+O-2 (Lu et al., 2014), we investigate the dominant channels for the production and loss of atomic carbon, against a subsolar background atmosphere based on MAVEN Deep Dip 2 observations. We confirm the results from previous studies that CO photodissociation and CO+ dissociative recombination are important contributors to atomic C production, and that reaction with O-2 to form CO is the main loss channel. However, we also find significant contributions from CO2 + -> h nu -> C + O-2 , HCO+ + e -> C + OH and charge exchange of C+ with CO2 . These additional production channels give rise to significantly higher C densities than have been previously reported, with a peak at 4 x 10(5) cm(-3) at a CO2 density of 1.7 x 10(10) cm(-3) (similar to 146 km altitude). We find the C densities to vary with H2O densities over a Martian year, with the wetter perihelion season having 13% lower C column densities. Contrary to Anbar et al.(1993), we find C densities to be relatively insensitive to the temperature-dependence of cross-sections for CO2 and CO photodissociation. A good understanding of carbon photochemistry in the present-day Martian atmosphere provides the essential foundational framework for determining the fate of atmospheric carbon in the study of Mars' climate evolution.
    • Factors Associated With the Recurrence, Persistence, and Clearance of Asymptomatic Bacterial Vaginosis Among Young African American Women: A Repeated-Measures Latent Class Analysis

      Coudray, Makella S; Sheehan, Diana M; Li, Tan; Cook, Robert L; Schwebke, Jane; Madhivanan, Purnima; Univ Arizona, Dept Hlth Promot Sci, Mel & Enid Zuckerman Coll Publ Hlth; Univ Arizona, Coll Med, Div Infect Dis; Univ Arizona, Coll Med, Dept Family & Community Med (LIPPINCOTT WILLIAMS & WILKINS, 2020-12)
      Background Although risk factors of recurrent and persistent bacterial vaginosis (BV) have been explored in the literature, the longitudinal incidence patterns of BV remain elusive. Methods We conducted a secondary analysis of longitudinal data from a randomized clinical trial of metronidazole treatment for asymptomatic BV. Repeated-measures latent class analysis was used to identify distinct longitudinal patterns of incident BV cases. Multinomial regression analysis was used to determine the predictors of class membership. The multivariable model included age, last BV treatment, douching frequency, birth control, sexual risk behavior, and assignment to treatment arm. Results A total of 858 African American women who were asymptomatic for BV were included in the analysis. Three emergent patterns of BV for 12 months were identified by repeated-measures latent class analysis: persistent (55.9%), recurrent (30.5%), and clearance (13.5%). Participants who had douched at least once had significantly lower odds to be in the recurrent class versus the clearance class (adjusted odds ratio [adjOR], 0.55; 95% confidence interval [CI], 0.18-0.63). Women who had sex with women had significantly lower odds of belonging to the persistent class versus the clearance class (adjOR, 0.38; 95% CI, 0.22-0.68) and the recurrent class (adjOR, 0.43; 95% CI, 0.23-0.81). Those who were assigned to the treatment arm had significantly increased odds of being in the recurrent class versus the clearance class (adjOR, 1.92; 95% CI, 1.22-3.03). Women older than 21 years were significantly more likely to be in the recurrent class (adjOR, 1.88; 95% CI, 1.17-3.00) than in the clearance class. Conclusions Assessment of BV cases revealed distinct patterns of recurrence and persistence of BV, which were significantly associated with douching, being in the treatment arm, and being a woman who had sex with women.
    • Masculine Capital / Yuppie Patriarchy: Visualizing the Noir Commodity in American Psycho

      Rischard, Mattius; Univ Arizona (UNIV TEXAS PRESS, 2020-12)
      In American Psycho, Patrick Bateman's narratological function is as a pastiche of cognitive and cultural dissonance resulting from deregulated commodity fetishism. Mary Harron's film adaptation sharpens his schizoid parody of 1980s Wall Street with film noir elements such as low-key lighting, subjective A/V techniques, and minimalist mise-en-scene, which enables opportunities for critiquing the relationship between commodification in the yuppie cultural mythos and visual consumption of the body.
    • Advanced Pointing Imaging Camera (APIC) for planetary science and mission opportunities

      Park, Ryan S.; Riedel, Joseph E.; Ermakov, Anton I.; Roa, Javier; Castillo-Rogez, Julie; Davies, Ashley G.; McEwen, Alfred S.; Watkins, Michael M.; Univ Arizona, Lunar & Planetary Lab (Elsevier BV, 2020-12)
      The Advanced Pointing Imaging Camera (APIC) is designed to obtain high-resolution imaging data to measure a target's geophysical and geodetic properties. The development of APIC originates from NASA's Homesteader program of technology development for candidate New Frontiers missions. The unique science enabled by APIC derives from its ability to simultaneously take images of the target and star field, allowing high-precision camera pointing knowledge with each high-resolution target image. APIC is small (28 cm x 18 cm x 24 cm encompassing volume), light-weight (6 kg total), and moderate in power (13 W maximum) while being high performance and robust to long missions in deep space. APIC incorporates two imagers, one narrow-angle camera (NAC) and one wide-angle camera (WAC) that can operate simultaneously. Both cameras utilize the CMOS-based Mars 2020 Engineering Camera technology with an option of either clear or Red-Green-Blue colors and have wide apertures to enable short exposures and thus perform a a wide range of targets. The NAC has a pixel resolution of 18 mu rad and 4 degrees field of view and the WAC has a pixel resolution of 82 mu rad and 18 degrees field of view. APIC also has two gimbals, allowing rapid camera pointing updates without the need to change the spacecraft attitude; thus, not interfering with other onboard sensors or spacecraft operations. Both gimbals are capable of compensating for relative spacecraft-target motion (i.e., image motion compensation) with an angular speed of up to 3075 (i.e., 0.5 rad/s). Many of APIC components are commercial-off-the-shelf (COTS), or adapted from other NASA flight programs, which makes APIC very competitive in cost and gives it a high technical maturity. APIC's high-resolution images enable the determination of high-accuracy topography for geologic studies. This paper presents details of APIC's characteristics and functionalities as well as specific science objectives that APIC data can address, such as measuring a geometric tidal flexing through estimating the tidal Love number, h(2) and l(2), and small rotational effects, such as libration and precession, of natural satellites and small bodies (i.e., asteroids and comets) that are key to exploring a planetary body's interior. Improved knowledge of spacecraft orbit via landmark tracking using the APIC data would also improve the recovery of low-degree gravitational parameters such as k(2). In this paper, the performance of APIC is presented by showing how well the tidal deformation and libration measurements can be recovered with realistic mission scenarios and configurations.
    • Risk Assessment of the Cardiac Pregnant Patient

      Siu, Samuel C; Evans, Kari L; Foley, Michael R; Univ Arizona, Dept Obstet & Gynecol, Coll Med (LIPPINCOTT WILLIAMS & WILKINS, 2020-12)
      Women with heart disease are at increased risk for maternal and fetal complications in pregnancy. Therefore, all women with heart disease should undergo evaluation and counseling, ideally before conception, or as early in pregnancy as possible. In this article we will review the role of risk assessment, the history of development of the cardiac risk prediction tools, and the role of current cardiac risk prediction tools.
    • Excited bottomonia in quark-gluon plasma from lattice QCD

      Larsen, Rasmus; Meinel, Stefan; Mukherjee, Swagato; Petreczky, Peter; Univ Arizona, Dept Phys (ELSEVIER, 2020-11-26)
      We present the first lattice QCD study of up to 3S and 2P bottomonia at non-zero temperatures. Correlation functions of bottomonia were computed using novel bottomonium operators and a variational technique, within the lattice non-relativistic QCD framework. We analyzed the bottomonium correlation functions based on simple physically-motivated spectral functions. We found evidence of sequential in-medium modifications, in accordance with the sizes of the bottomonium states.
    • State/Nation Histories, Structural Inequalities and Racialised Crises

      Peterson, V. Spike; Univ Arizona, Sch Govt & Publ Policy (ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD, 2020-11-24)
      This paper draws attention to blind spots in understandings of 'the state' in International Political Economy. A genealogy of political centralisation that begins not with modern but the earliest (ancient) states reveals the requisites of successful state formation and how these constitute structural inequalities with enduring effects. Stark inequalities within and between nations figure in producing and exacerbating myriad problems, even global crises. I focus here on how economic inequalities are historically shaped by and today are variously reproducing racial logics that percolate through and exacerbate a global rise in xenophobia, alt-right nationalisms and anti-migrant hostilities. I trace linkages among inheritance, birthright citizenship, economic 'gaps' and immigration policies to reveal racial logics shaping the practices, policies and institutions of today's global political economy. Historically, my broad-stroke survey illuminates how states - through coercion, regulation and legitimation - produce and sustain the social violence of intersecting structural inequalities, and how we are 'blinded' to this by normalisation of ideologies that both reproduce and mask operations of power. Methodologically, my account argues that in a state-based system, 'economic' inequalities are never simply that, but always (though variously and complexly) produced by and producing racialised, sexualised and geopolitically differentiated inequalities.
    • Unrecognized pulmonary arterial hypertension in hospitalized patients

      Carpio, Andres Mora; Goertz, Aaron; Kelly, Colleen; Willes, Leslee; Quan, Stuart F; Pressman, Gregg S; Niroula, Abesh; Sharma, Sunil; Univ Arizona, Coll Med, Asthma & Airways Res Ctr (SPRINGER, 2020-11-19)
      Pulmonary hypertension (PH) is an underdiagnosed and potentially fatal condition. The utility of screening for PH in hospitalized patients undergoing echocardiography is unknown. The goal of this study was to determine the prevalence of undiagnosed pulmonary hypertension (PH) and probable pulmonary arterial hypertension (PAH) in hospitalized patients undergoing echocardiography for any indication. All hospitalized patients undergoing echocardiography were identified and echocardiographs reviewed prospectively for the presence of a tricuspid regurgitant (TR) jet. Electronic medical records (EMR) of patients with a TR jet >= 3 m/s were reviewed for identifiable causes of pulmonary hypertension. Patients with no identifiable cause were classified as presumptive World Health Organization (WHO) Group 1 PH (also known as PAH). These PAH patients were compared to other PH patients for baseline demographic characteristics and comorbidities as well as 30-day readmission and mortality. The admitting physicians of patients classified as PH were advised to consider further evaluation including right heart catheterization. We reviewed 4417 consecutive echocardiograms and identified 448 with a TR jet >= 3 m/s. Of these 448 patients with PH, 47 were identified as "presumptive PAH" and the other 401 as having PH belonging to WHO Groups 2-5. Presumptive PAH represented 1% of screened echocardiograms and 10.5% of those identified to have an elevated TR jet. Of the patients identified as presumptive PAH, 8 underwent further evaluation including a right heart catheterization, where 5 were confirmed to have PAH. Kaplan-Meier analysis revealed 30-day readmission was higher among those classified as PAH. Our data shows that pulmonary hypertension, as defined by TR jet >= 3 m/s, is frequently encountered in hospitalized patients undergoing echocardiography for any reason. A careful review of echocardiogram findings and clinical history suggested 10.5% of those with PH (and 1% of all screened patients) may meet the criteria for PAH. Considering PH is a fatal condition which is frequently missed, a hospital screening program seems feasible.
    • Cannabinoid-2 Agonism with AM2301 Mitigates Morphine-Induced Respiratory Depression

      Wiese, Beth M.; Liktor-Busa, Erika; Levine, Aidan; Couture, Sarah A.; Nikas, Spyros P.; Ji, Lipin; Liu, Yingpeng; Mackie, Kenneth; Makriyannis, Alexandros; Largent-Milnes, Tally M.; et al. (MARY ANN LIEBERT, INC, 2020-11-13)
      Introduction: An escalating number of fatalities resulting from accidental opioid overdoses typically attributed to respiratory depression continue to define the opioid epidemic. Opioid respiratory depression results from a decrease in reflexive inspiration within the preBotzinger complex in the brainstem. Objective: Cannabinoid receptor agonism is reported to enhance opioid analgesia, yet whether cannabinoids enhance or inhibit opioid-induced respiratory depression is unknown. Methods: Studies herein sought to define the roles of cannabinoid-1 receptor (CB1R) and cannabinoid-2 receptor (CB2R) on respiratory depression using selective agonists alone and in combination with morphine in male mice. Results: Using whole body plethysmography, the nonselective CB1R and CB2R agonist (Delta(9)-tetrahydrocannabinol) and the CB1R synthetic cannabinoid, AM356, induced respiratory depression, whereas the well-published selective CB2 agonist, JWH 133, and the novel CB2 agonist (AM2301) did not. Moreover, a selective CB2R agonist (AM2301) significantly attenuated morphine sulfate-induced respiratory depression. Conclusion: Notably, findings suggest that attenuation of opioid-induced respiratory depression relies on CB2R activation, supporting selective CB2R agonism as an opioid adjunct therapy.
    • Growth and biochemical responses of sorghum genotypes to nitrogen fertilizer under salinity stress conditions

      Zamani, Afshin; Emam, Yahya; Pessarakli, Mohammad; Shakeri, Ehsan; Univ Arizona, Coll Agr & Life Sci, Sch Plant Sci (TAYLOR & FRANCIS INC, 2020-11-13)
      This study was carried out to assess the efficiency of nitrogen (N) fertilizer in mitigating the harmful effects of salinity stress on growth and biochemical traits in sorghum genotypes. The experiment was conducted as a factorial trial based on the completely randomized design with four replications under the greenhouse conditions. The factors included four sorghum genotypes (KDFGS1, KDFGS23, KDFGS29 lines, and KFS2 cultivar), two salinity levels (3 and 12 dS m(-1)) and three nitrogen levels (0, 75 and 150 mg N kg(-1)soil). The results showed that application of nitrogen fertilizer increased photosynthetic pigments and K+/Na+ ratio in leaf sheath and root. Also, nitrogen dramatically decreased malondialdehyde (MDA) content. This was an indication of the reduced detrimental effects of salinity stress found in all genotypes. In addition, it was found that upon 150 mg N kg(-1) treatments, proline (Pro) and antioxidant enzymes markedly decreased in all sorghum genotypes. The highest impact of nitrogen fertilizer for reducing the negative effect of salinity stress was observed in KFS2 (known as tolerant genotype). Due to the highest Pro accumulation in KDFGS23 (known as sensitive genotype), it did not appear to be a suitable criterion for the selection of the tolerant lines/cultivars. In general, the results suggested that using a reasonable N fertilizer level could be used as an efficient tool to improve the growth of the sorghum genotypes subjected to salinity stress and this effect was more pronounced in the tolerant genotype.
    • Simple rules for a more inclusive economy

      Tarko, Vlad; Univ Arizona, Dept Polit Econ & Moral Sci (SPRINGER, 2020-11-13)
      This paper explores some of the reasons why capitalism experiences periodic crises of legitimacy and asks whether Richard Epstein's "simple rules" heuristic can help. The current legitimacy problem is exacerbated by the fact that we are also in a low growth situation. This means that some policy instruments that could have been used to increase legitimacy may no longer be available. The "simple rules" heuristic can help as a guide to reforms that would simultaneously address the legitimacy problem, while avoiding making the growth problem worse.
    • Hydrogen escape from Mars is driven by seasonal and dust storm transport of water

      Stone, Shane W; Yelle, Roger V; Benna, Mehdi; Lo, Daniel Y; Elrod, Meredith K; Mahaffy, Paul R; Univ Arizona, Lunar & Planetary Lab (AMER ASSOC ADVANCEMENT SCIENCE, 2020-11-13)
      Mars has lost most of its once-abundant water to space, leaving the planet cold and dry. In standard models, molecular hydrogen produced from water in the lower atmosphere diffuses into the upper atmosphere where it is dissociated, producing atomic hydrogen, which is lost. Using observations from the Neutral Gas and Ion Mass Spectrometer on the Mars Atmosphere and Volatile Evolution spacecraft, we demonstrate that water is instead transported directly to the upper atmosphere, then dissociated by ions to produce atomic hydrogen. The water abundance in the upper atmosphere varied seasonally, peaking in southern summer, and surged during dust storms, including the 2018 global dust storm. We calculate that this transport of water dominates the present-day loss of atomic hydrogen to space and influenced the evolution of Mars' climate.