Now showing items 13417-13436 of 13762

    • Vesicular trafficking permits evasion of cGAS/STING surveillance during initial human papillomavirus infection

      Uhlorn, Brittany L.; Jackson, Robert; Li, Shuaizhi; Bratton, Shauna M.; Van Doorslaer, Koenraad; Campos, Samuel K.; Univ Arizona, Canc Biol Grad Interdisciplinary Program; Univ Arizona, Sch Anim & Comparat Biomed Sci; Univ Arizona, Dept Immunobiol; Univ Arizona, Dept Physiol; et al. (PUBLIC LIBRARY SCIENCE, 2020)
      Oncogenic human papillomaviruses (HPVs) replicate in differentiating epithelium, causing 5% of cancers worldwide. Like most other DNA viruses, HPV infection initiates after trafficking viral genome (vDNA) to host cell nuclei. Cells possess innate surveillance pathways to detect microbial components or physiological stresses often associated with microbial infections. One of these pathways, cGAS/STING, induces IRF3-dependent antiviral interferon (IFN) responses upon detection of cytosolic DNA. Virion-associated vDNA can activate cGAS/STING during initial viral entry and uncoating/trafficking, and thus cGAS/STING is an obstacle to many DNA viruses. HPV has a unique vesicular trafficking pathway compared to many other DNA viruses. As the capsid uncoats within acidic endosomal compartments, minor capsid protein L2 protrudes across vesicular membranes to facilitate transport of vDNA to the Golgi. L2/vDNA resides within the Golgi lumen until G2/M, whereupon vesicular L2/vDNA traffics along spindle microtubules, tethering to chromosomes to access daughter cell nuclei. L2/vDNA-containing vesicles likely remain intact until G1, following nuclear envelope reformation. We hypothesize that this unique vesicular trafficking protects HPV from cGAS/STING surveillance. Here, we investigate cGAS/STING responses to HPV infection. DNA transfection resulted in acute cGAS/STING activation and downstream IFN responses. In contrast, HPV infection elicited minimal cGAS/STING and IFN responses. To determine the role of vesicular trafficking in cGAS/STING evasion, we forced premature viral penetration of vesicular membranes with membrane-perturbing cationic lipids. Such treatment renders a non-infectious trafficking-defective mutant HPV infectious, yet susceptible to cGAS/STING detection. Overall, HPV evades cGAS/STING by its unique subcellular trafficking, a property that may contribute to establishment of infection. Author summary Persistent infection is the main risk factor for all HPV-associated cancers. However, cellular innate immune pathways exist to detect and limit viral infections. The cGAS/STING pathway senses cytosolic DNA to initiate antiviral IFN responses. Such responses would likely be detrimental towards the establishment of persistent HPV infections. We therefore hypothesize that HPV evades cGAS/STING detection via its unique vesicular trafficking mechanism. Here, we show that indeed HPV is a stealthy virus, capable of infecting keratinocytes with minimal activation of the cGAS/STING pathway. Such evasion is dependent on HPV's vesicular trafficking, as perturbation of vesicular integrity during infection results in sensing of virions.
    • Vesicular trafficking plays a role in centriole disengagement and duplication

      Xie, Shuwei; Reinecke, James B; Farmer, Trey; Bahl, Kriti; Yeow, Ivana; Nichols, Benjamin J; McLamarrah, Tiffany A; Naslavsky, Naava; Rogers, Gregory C; Caplan, Steve; et al. (AMER SOC CELL BIOLOGY, 2018-11-01)
      Centrosomes are the major microtubule-nucleating and microtubule-organizing centers of cells and play crucial roles in microtubule anchoring, organelle positioning, and ciliogenesis. At the centrosome core lies a tightly associated or "engaged" mother-daughter centriole pair. During mitotic exit, removal of centrosomal proteins pericentrin and Cep215 promotes "disengagement" by the dissolution of intercentriolar linkers, ensuring a single centriole duplication event per cell cycle. Herein, we explore a new mechanism involving vesicular trafficking for the removal of centrosomal Cep215. Using small interfering RNA and CRISPR/ Cas9 gene-edited cells, we show that the endocytic protein EHD1 regulates Cep215 transport from centrosomes to the spindle midbody, thus facilitating disengagement and duplication. We demonstrate that EHD1 and Cep215 interact and show that Cep215 displays increased localization to vesicles containing EHD1 during mitosis. Moreover, Cep215-containing vesicles are positive for internalized transferrin, demonstrating their endocytic origin. Thus, we describe a novel relationship between endocytic trafficking and the centrosome cycle, whereby vesicles of endocytic origin are used to remove key regulatory proteins from centrosomes to control centriole duplication.
    • Vetting of 384 TESS Objects of Interest with TRICERATOPS and Statistical Validation of 12 Planet Candidates

      Giacalone, Steven; Dressing, Courtney D.; Jensen, Eric L. N.; Collins, Karen A.; Ricker, George R.; Vanderspek, Roland; Seager, S.; Winn, Joshua N.; Jenkins, Jon M.; Barclay, Thomas; et al. (IOP PUBLISHING LTD, 2020-12-11)
      We present TRICERATOPS, a new Bayesian tool that can be used to vet and validate TESS Objects of Interest (TOIs). We test the tool on 68 TOIs that have been previously confirmed as planets or rejected as astrophysical false positives. By looking in the false-positive probability (FPP)-nearby false-positive probability (NFPP) plane, we define criteria that TOIs must meet to be classified as validated planets (FPP < 0.015 and NFPP < 10(-3)), likely planets (FPP < 0.5 and NFPP < 10(-3)), and likely nearby false positives (NFPP > 10(-1)). We apply this procedure on 384 unclassified TOIs and statistically validate 12, classify 125 as likely planets, and classify 52 as likely nearby false positives. Of the 12 statistically validated planets, 9 are newly validated. TRICERATOPS is currently the only TESS vetting and validation tool that models transits from nearby contaminant stars in addition to the target star. We therefore encourage use of this tool to prioritize follow-up observations that confirm bona fide planets and identify false positives originating from nearby stars.
    • Viability of slow-roll inflation in light of the non-zero k(min) measured in the cosmic microwave background power spectrum

      Liu, Jingwei; Melia, Fulvio; Univ Arizona, Dept Phys; Univ Arizona, Dept Phys, Appl Math Program; Univ Arizona, Dept Astron (The Royal Society, 2020-07)
      Slow-roll inflation may simultaneously solve the horizon problem and generate a near scale-free fluctuation spectrum P(k). These two processes are intimately connected via the initiation and duration of the inflationary - phase. But a recent study based on the latest Planck release suggests that P(k) has a hard cut off, k(min) not equal 0, inconsistent with this conventional picture. Here, we demonstrate quantitatively that most-perhaps all-slow-roll inflationary models fail to accommodate this minimum cut-oft. We show that the small parameter epsilon must be greater than or similar to 0.9 throughout the inflationary period to comply with the data, seriously violating the slow-roll approximation. Models with such an epsilon predict extremely red spectral indices, at odds with the measured value. We also consider extensions to the basic picture (suggested by several earlier workers) by adding a kinetic-dominated or radiation-dominated phase preceding the slow-roll expansion. Our approach differs from previously published treatments principally because we require these modifications not only to fit the measured fluctuation spectrum but also simultaneously to fix the horizon problem. We show, however, that even such measures preclude a joint resolution of the horizon problem and the missing correlations at large angles.
    • The Viability of Using Rapid Judgments as a Method of Deception Detection

      Dunbar, Norah E.; Jensen, Matthew L.; Harvell-Bowman, Lindsey A.; Kelley, Katherine M.; Burgoon, Judee K.; Univ Arizona (ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD, 2017-01-25)
      Rapid Judgments (RJs) are quick assessments based on indirect verbal and nonverbal cues that are known to be associated with deception. RJs are advantageous because they eliminate the need for expensive detection equipment and only require minimal training for coders with relatively accurate judgments. Results of testing on two different datasets showed that trained coders were reliably making RJs after watching both long and short interaction segments but their judgments were not more accurate than the expert interviewers. The RJs did not discriminate between truth and deception as hypothesized. This raises more questions about the conditions under which making RJs from verbal and nonverbal cues achieves accurate detection of veracity.
    • Viable spores of Coccidioides posadasii Δcps1 are required for vaccination and provide long lasting immunity

      Shubitz, Lisa F.; Powell, Daniel A.; Trinh, Hien T.; Lewis, M. Lourdes; Orbach, Marc J.; Frelinger, Jeffrey A.; Galgiani, John N.; Univ Arizona, Valley Fever Ctr Excellence; Univ Arizona, Dept Immunobiol; Univ Arizona, Sch Plant Sci; et al. (ELSEVIER SCI LTD, 2018)
      Coccidioidomycosis is a systemic fungal infection for which a vaccine has been sought for over fifty years. The avirulent Coccidioides posadasii strain, Delta cps1 which is missing a 6 kb gene, showed significant protection in mice. These studies explore conditions of protection in mice and elucidate the immune response. Mice were vaccinated with different doses and viability states of Delta cps1 spores, challenged with virulent C posadasii, and sacrificed at various endpoints, dependent on experimental objectives. Tissues from vaccinated mice were harvested for in vitro elucidation of immune response. Vaccination with viable Delta cps1 spores was required for protection from lethal challenge. Viable spore vaccination produced durable immunity, lasting at least 6 months, and prolonged survival (>= 6 months). The C. posadasii vaccine strain also protected mice against C immitis (survival >= 6 months). Cytokines from infected lungs of vaccinated mice in the first four days after Cp challenge showed significant increases of IFN-gamma, as did stimulated CD4(+) spleen cells from vaccinated mice. Transfer of CD4(+) cells, but not CD8(+) or B cells, reduced fungal burdens following challenge. IFN-gamma from CD4(+) cells in vaccinated mice indicates a Th1 response, which is critical for host control of coccidioidomycosis. (C) 2018 Elsevier Ltd. All rights reserved.
    • Vibrations in MagAO: frequency-based analysis of on-sky data, resonance sources identification, and future challenges in vibrations mitigation

      Zúñiga, Sebastián; Garcés, Javier; Close, Laird M.; Males, Jared R.; Morzinski, Katie M.; Escárate, Pedro; Castro, Mario; Marchioni, José; Zagals, Diego; Univ Arizona, Dept Astron, CAAO; et al. (SPIE-INT SOC OPTICAL ENGINEERING, 2016-07-27)
      Frequency-based analysis and comparisons of tip-tilt on-sky data registered with 6.5 Magellan Telescope Adaptive Optics (MagAO) system on April and Oct 2014 was performed. Twelve tests are conducted under different operation conditions in order to observe the influence of system instrumentation (such as fans, pumps and louvers). Vibration peaks can be detected, power spectral densities (PSDs) are presented to reveal their presence. Instrumentation-induced resonances, close-loop gain and future challenges in vibrations mitigation techniques are discussed.
    • Vibrations in MagAO: resonance sources identification and first approaches for modeling and control

      Garcés, Javier; Zúñiga, Sebastián; Close, Laird; Males, Jared; Morzinski, Katie; Escárate, Pedro; Castro, Mario; Marchioni, José; Rojas, Diego; Univ Arizona, Steward Observ; et al. (SPIE-INT SOC OPTICAL ENGINEERING, 2016-07-27)
      The Magellan Telescope Adaptive Optics System (MagAO) is subject to resonance effects induced by elements within the system instrumentation, such as fans and cooling pumps. Normalized PSDs are obtained through frequency-based analysis of closed-loop on-sky data, detecting and measuring vibration effects. Subsequently, a space-state model for the AO loop is obtained, using a standard AO loop scheme with an integrator-based controller and including the vibration effects as disturbances. Finally, a new control alternative is proposed, focusing on residual phase variance minimization through the design and simulation of an optimal LQG control approach.
    • Vicarious Calibration of eMAS, AirMSPI, and AVIRIS Sensors During FIREX-AQ

      Bruegge, Carol J.; Arnold, G. Thomas; Czapla-Myers, Jeffrey; Dominguez, RoseAnne; Helmlinger, Mark C.; Thompson, David R.; Van den Bosch, Jeannette; Wenny, Brian N.; Wyant College of Optical Sciences, The University of Arizona (Institute of Electrical and Electronics Engineers (IEEE), 2021)
      Remote sensing instruments, both aircraft and on-orbit platforms, undergo extensive laboratory calibrations to determine their geometric, spectral, and radiometric responses. Additional in-flight radiometric calibrations can be performed using well-characterized earth targets. The Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) campaign provided such an opportunity when the ER-2 aircraft overflew Railroad Valley on August 13 and 15, 2019. Surface reflectances were available from the August 4, 2019 field team and from the Radiometric Calibration Network (RadCalNet) portal, and spectral aerosol optical depths from an on-site AERosol RObotic NETwork (AERONET) sunphotometer. The Enhanced MODIS Airborne Simulator (eMAS), the Airborne Multiangle SpectroPolarimetric Imager (AirMSPI), and the ``Classic'' Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-C) sensors individually performed a vicarious calibration using their respective methodologies and selection of input parameters. A comparison of the at-sensor radiances predicted from these independent analyses highlights some of the uncertainties in the inputs, including choice of solar irradiance model. Although good agreement, within 5%, is found at visible wavelengths, difference can be as large as 15% in the shortwave infrared (SWIR). This highlights the need for the remote sensing community to agree upon a standard solar model, to remove sensor-to-sensor biases derived from in-flight calibrations.
    • Victim voice in reenvisioning responses to sexual and physical violence nationally and internationally.

      Koss, Mary P.; White, Jacquelyn W.; Lopez, Elise C.; Univ Arizona, Mel & Enid Zuckerman Coll Publ Hlth, Dept Hlth Promot Sci (AMER PSYCHOLOGICAL ASSOC, 2017-12)
      Internationally and in the United States many victims of sexual assault and domestic violence are unserved, underserved, or ill-served, especially those from the most vulnerable populations. Programs developed in the United States are routinely exported to developing countries but often without success. Notably, the failures seen internationally resemble those in the United States and are related to structural and attitudinal-cultural factors. Many victims do not disclose, and if they do seek services, they often report that available options mismatch their objectives, present accessibility challenges, disempower their pursuit of justice, and fail to augment needed resources. A deeper understanding of obstacles to effective service provision is needed if the United States is to continue to be an international partner in victim response and violence prevention. This article builds on what is known about service delivery challenges in U.S. programs to envision a path forward that concomitantly accommodates anticipation of shrinking resources, by (a) reviewing illustrative services and feedback from victims about utilizing them; (b) examining structural inequalities and the intersections of personal and contextual features that both increase vulnerability to victimization and decrease accessibility and acceptability of services; (c) advocating for reintroduction of direct victim voice into response planning to enhance reach and relevance; and (d) reorienting delivery systems, community partnerships, and Coordinated Community Response teams. The authors suggest as the way forward pairing direct victim voice with open-minded listening to expressed priorities, especially in vulnerable populations, and designing services accordingly. Through a process that prioritizes adaptation to diverse needs and cultures, U.S models can increase desirability, equity, and thrift at home as well as enhance international relevance.
    • Video laryngoscopy improves intubation success and reduces esophageal intubations compared to direct laryngoscopy in the medical intensive care unit

      Mosier, Jarrod; Whitmore, Sage; Bloom, John; Snyder, Linda; Graham, Lisa; Carr, Gordon; Sakles, John; Department of Emergency Medicine, University of Arizona, Tucson, AZ, USA; Department of Medicine, Section of Pulmonary, Critical Care, Allergy and Sleep, University of Arizona, 1609 N Warren, FOB 122C, Tucson, AZ 85719, USA (BioMed Central, 2013)
      INTRODUCTION:Tracheal intubation in the Intensive Care Unit (ICU) can be challenging as patients often have anatomic and physiologic characteristics that make intubation particularly difficult. Video laryngoscopy (VL) has been shown to improve first attempt success compared to direct laryngoscopy (DL) in many clinical settings and may be an option for ICU intubations.METHODS:All intubations performed in this academic medical ICU during a 13-month period were entered into a prospectively collected quality control database. After each intubation, the operator completed a standardized form evaluating multiple aspects of the intubation including: patient demographics, difficult airway characteristics (DACs), method and device(s) used, medications used, outcomes and complications of each attempt. Primary outcome was first attempt success. Secondary outcomes were grade of laryngoscopic view, ultimate success, esophageal intubations, and desaturation. Multivariate logistic regression was performed for first attempt and ultimate success.RESULTS:Over the 13-month study period (January 2012-February 2013), a total of 234 patients were intubated using VL and 56 patients were intubated with DL. First attempt success for VL was 184/234 (78.6%
    • Vihvelin on Frankfurt-Style Cases and the Actual-Sequence View

      Sartorio, Carolina; University of Arizona (Springer, 2014-11-11)
      This is a critical discussion of Vihvelin's recent book Causes, Laws, and Free Will. I discuss Vihvelin's ideas on Frankfurt-style cases and the actual-sequence view of freedom that is inspired by them.
    • A Villin-Driven Fxr Transgene Modulates Enterohepatic Bile Acid Homeostasis and Response to an n-6-Enriched High-Fat Diet

      Wren, Spencer N; Donovan, Micah G; Selmin, Ornella I; Doetschman, Tom C; Romagnolo, Donato F; Univ Arizona, Dept Nutr Sci; Univ Arizona, Interdisciplinary Canc Biol Grad Program; Univ Arizona, Canc Ctr; Univ Arizona, Dept Cellular & Mol Med (MDPI, 2020-10-22)
      A diet high in n-6 polyunsaturated fatty acids (PUFAs) may contribute to inflammation and tissue damage associated with obesity and pathologies of the colon and liver. One contributing factor may be dysregulation by n-6 fatty acids of enterohepatic bile acid (BA) metabolism. The farnesoid X receptor (FXR) is a nuclear receptor that regulates BA homeostasis in the liver and intestine. This study aims to compare the effects on FXR regulation and BA metabolism of a palm oil-based diet providing 28% energy (28%E) from fat and low n-6 linoleic acid (LA, 2.5%E) (CNTL) with those of a soybean oil-based diet providing 50%E from fat and high (28%E) in LA (n-6HFD). Wild-type (WT) littermates and a transgenic mouse line overexpressing the Fxrα1 isoform under the control of the intestine-specific Villin promoter (Fxrα1TG) were fed the CNTL or n-6HFD starting at weaning through 16 weeks of age. Compared to the CNTL diet, the n-6HFD supports higher weight gain in both WT and FxrαTG littermates; increases the expression of Fxrα1/2, and peroxisome proliferator-activated receptor-γ1 (Pparγ1) in the small intestine, Fxrα1/2 in the colon, and cytochrome P4507A1 (Cyp7a1) and small heterodimer protein (Shp) in the liver; and augments the levels of total BA in the liver, and primary chenodeoxycholic (CDCA), cholic (CA), and β-muricholic (βMCA) acid in the cecum. Intestinal overexpression of the Fxra1TG augments expression of Shp and ileal bile acid-binding protein (Ibabp) in the small intestine and Ibabp in the proximal colon. Conversely, it antagonizes n-6HFD-dependent accumulation of intestinal and hepatic CDCA and CA; hepatic levels of Cyp7a1; and expression of Pparγ in the small intestine. We conclude that intestinal Fxrα1 overexpression represses hepatic de novo BA synthesis and protects against n-6HFD-induced accumulation of human-specific primary bile acids in the cecum.
    • “Violations as Profound as Any Rape”

      Wise, Dennis Wilson; Univ Arizona (LIVERPOOL UNIVERSITY PRESS, 2019-07)
      In the last few years, literary representations of sexed violence (sometimes known as "gender violence") have been increasingly scrutinized. Such scrutiny has made some aspects in the work of Stephen R. Donaldson, who frequently employs rape as a theme, disquieting. This article attempts a critical intervention on Donaldson's behalf. First, I situate Donaldson vis-a-vis his engagement with second wave radical feminism, particularly in terms of reinterpreting rape as a matter of power. Then I pose a number of postmodern feminist challenges to Donaldson's two major epics, The Chronicles of Thomas Covenant the Unbeliever and the Gap sequence. Ultimately, I find that his core existential humanism nonetheless produces some valuable insights into the men who commit acts of sexed violence.
    • Violence and Perimortem Signaling among Early Irrigation Communities in the Sonoran Desert

      Watson, James T.; Phelps, Danielle O.; Univ Arizona, Sch Anthropol (UNIV CHICAGO PRESS, 2016-10-02)
      Violence is common among small-scale societies and often stems from a combination of exogenous and endogenous factors. We suggest that socialization for violence and revenge as a motivation can encourage costly signaling by warriors and contribute to the creation of atypical burials in archaeological contexts. We characterize mortuary patterns among early irrigation communities in the Sonoran Desert of the southwest United States/northwest Mexico (Early Agricultural period: 2100 BC-AD 50) to define normative mortuary practices and identify atypical burials. One of the principle roles the performance of mortuary rituals fulfills is to publicly integrate a shared identity or reinforce social differences within a community. This postmortem negotiation of social identities was likely an important component to ease social tensions in early farming communities. However, atypical burials from these sites appear to represent acts of violence upon the corpse at, or after, the death of the individual that fall outside of the normative conformity to prescribed mortuary ritual. We propose that these cases represent perimortem signaling, a form of costly signaling conditioned as basal violent reactions, possibly stemming from socialization for violence.
    • Violence: heightened brain attentional network response is selectively muted in Down syndrome

      Anderson, Jeffrey S.; Treiman, Scott M.; Ferguson, Michael A.; Nielsen, Jared A.; Edgin, Jamie O.; Dai, Li; Gerig, Guido; Korenberg, Julie R.; Department of Radiology, 1A71 School of Medicine, University of Utah; Interdepartmental Program in Neuroscience, University of Utah; et al. (Springer, 2015)
      BACKGROUND: The ability to recognize and respond appropriately to threat is critical to survival, and the neural substrates subserving attention to threat may be probed using depictions of media violence. Whether neural responses to potential threat differ in Down syndrome is not known. METHODS: We performed functional MRI scans of 15 adolescent and adult Down syndrome and 14 typically developing individuals, group matched by age and gender, during 50 min of passive cartoon viewing. Brain activation to auditory and visual features, violence, and presence of the protagonist and antagonist were compared across cartoon segments. fMRI signal from the brain's dorsal attention network was compared to thematic and violent events within the cartoons between Down syndrome and control samples. RESULTS: We found that in typical development, the brain's dorsal attention network was most active during violent scenes in the cartoons and that this was significantly and specifically reduced in Down syndrome. When the antagonist was on screen, there was significantly less activation in the left medial temporal lobe of individuals with Down syndrome. As scenes represented greater relative threat, the disparity between attentional brain activation in Down syndrome and control individuals increased. There was a reduction in the temporal autocorrelation of the dorsal attention network, consistent with a shortened attention span in Down syndrome. Individuals with Down syndrome exhibited significantly reduced activation in primary sensory cortices, and such perceptual impairments may constrain their ability to respond to more complex social cues such as violence. CONCLUSIONS: These findings may indicate a relative deficit in emotive perception of violence in Down syndrome, possibly mediated by impaired sensory perception and hypoactivation of medial temporal structures in response to threats, with relative preservation of activity in pro-social brain regions. These findings indicate that specific genetic differences associated with Down syndrome can modulate the brain's response to violence and other complex emotive ideas.
    • VIP: Vortex Image Processing Package for High-contrast Direct Imaging

      Gomez Gonzalez, Carlos Alberto; Wertz, Olivier; Absil, O.; Christiaens, Valentin; Defrère, D.; Mawet, Dimitri; Milli, Julien; Absil, Pierre-Antoine; Van Droogenbroeck, Marc; Cantalloube, Faustine; et al. (IOP PUBLISHING LTD, 2017-06-12)
      We present the Vortex Image Processing (VIP) library, a python package dedicated to astronomical high-contrast imaging. Our package relies on the extensive python stack of scientific libraries and aims to provide a flexible framework for high-contrast data and image processing. In this paper, we describe the capabilities of VIP related to processing image sequences acquired using the angular differential imaging (ADI) observing technique. VIP implements functionalities for building high-contrast data processing pipelines, encompassing pre- and post-processing algorithms, potential source. position and flux estimation, and sensitivity curve. generation. Among the reference point-spread. function subtraction techniques for ADI post-processing, VIP includes several flavors of principal component analysis (PCA) based algorithms, such as annular PCA and incremental PCA algorithms capable of processing big datacubes (of several gigabytes) on a computer with limited memory. Also, we present a novel ADI algorithm based on non-negative matrix factorization, which comes from the same family of low-rank matrix approximations as PCA and provides fairly similar results. We showcase the ADI capabilities of the VIP library using a deep sequence on HR 8799 taken with the LBTI/LMIRCam and its recently commissioned L-band vortex coronagraph. Using VIP, we investigated the presence of additional companions around HR 8799 and did not find any significant additional point source beyond the four known planets. VIP is available at http://github. com/vortex-exoplanet/VIP and is accompanied with Jupyter notebook tutorials illustrating the main functionalities of the library.
    • Viral elements and their potential influence on microbial processes along the permanently stratified Cariaco Basin redoxcline

      Mara, Paraskevi; Vik, Dean; Pachiadaki, Maria G.; Suter, Elizabeth A.; Poulos, Bonnie; Taylor, Gordon T.; Sullivan, Matthew B.; Edgcomb, Virginia P.; Univ Arizona, Dept Ecol & Evolutionary Biol (Springer Science and Business Media LLC, 2020-08-14)
      Little is known about viruses in oxygen-deficient water columns (ODWCs). In surface ocean waters, viruses are known to act as gene vectors among susceptible hosts. Some of these genes may have metabolic functions and are thus termed auxiliary metabolic genes (AMGs). AMGs introduced to new hosts by viruses can enhance viral replication and/or potentially affect biogeochemical cycles by modulating key microbial pathways. Here we identify 748 viral populations that cluster into 94 genera along a vertical geochemical gradient in the Cariaco Basin, a permanently stratified and euxinic ocean basin. The viral communities in this ODWC appear to be relatively novel as 80 of these viral genera contained no reference viral sequences, likely due to the isolation and unique features of this system. We identify viral elements that encode AMGs implicated in distinctive processes, such as sulfur cycling, acetate fermentation, signal transduction, [Fe-S] formation, and N-glycosylation. These AMG-encoding viruses include two putative Mu-like viruses, and viral-like regions that may constitute degraded prophages that have been modified by transposable elements. Our results provide an insight into the ecological and biogeochemical impact of viruses oxygen-depleted and euxinic habitats.
    • Viral video ‘blood chocolate’ activism, millennial anti-trafficking, and the neoliberal resurgence of shaming

      Lawrance, Benjamin N.; Roberts, Richard L.; Univ Arizona, Dept Hist (ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD, 2019-01-02)
      Viral videos offer contemporary activists a nimble, provocative tool with which to disseminate humanitarian messages. This article historicizes anti-trafficking video media that imagine a new potential with which to alter behavioral norms around cocoa and chocolate. The article engages theories and approaches to historical and contemporary modalities of naming and shaming, spanning three centuries to the present day. Videos are examined for style, format, and content, with the view to describing a 'blood chocolate' visual and textual metonymy. Recurring themes include transnational power, corporate responsibility, and the horrific scale of exploitation. But viral videos also appear deeply influenced by neoliberal economics that celebrate lawful enterprise and promote consumer-driven solutions to exploitative child labor.
    • Virtual axion-like particle Complement to Euler-Heisenberg-Schwinger action

      Evans, Stefan; Rafelski, Johann; Univ Arizona, Dept Phys (ELSEVIER SCIENCE BV, 2019-04-10)
      We modify action in an external electromagnetic field to include effects of virtual axion-like particle (ALP) excitations. A measurable addition to QED-Euler-Heisenberg-Schwinger (EHS) action is obtained and incorporated into experimental constraints placed on ALP mass and coupling to two photons. The regime of these constraints in which the ALP vacuum effect surpasses the EHS effect is characterized. We show that probing of the virtual vacuum effect offers an alternative method in search for physics related to ALPs. (C) 2019 The Authors. Published by Elsevier B.V.