ABOUT THIS COLLECTION

This open access archive contains publications from University of Arizona faculty, researchers and staff, primarily open-access versions of formally published journal articles. The collection includes published articles and final accepted manuscripts submitted by UA faculty under the UA Open Access Policy. The collection also includes books, book chapters, book reviews, presentations, data, and other scholarly materials submitters have chosen to make available in the repository.


HOW TO SUBMIT

  • Log in to the repository using your NetID and password
  • Click the "Submissions" link in the left sidebar (under "My Account")
  • Start a new submission in the UA Faculty Publications collection.
  • Library staff will check publisher policies, including embargo periods related to your submission.
  • You will receive an email with a persistent link to your submission when it is approved.

QUESTIONS?

Contact open-access@email.arizona.edu with your questions about the UA Faculty Publications collection.

Recent Submissions

  • Extreme temperature events will drive coral decline in the Coral Triangle

    McManus, Lisa C; Vasconcelos, Vítor V; Levin, Simon A; Thompson, Diane M; Kleypas, Joan A; Castruccio, Frederic S; Curchitser, Enrique N; Watson, James R; Univ Arizona, Dept Geosci (WILEY, 2019-12-27)
    In light of rapid environmental change, quantifying the contribution of regional- and local-scale drivers of coral persistence is necessary to characterize fully the resilience of coral reef systems. To assess multiscale responses to thermal perturbation of corals in the Coral Triangle (CT), we developed a spatially explicit metacommunity model with coral-algal competition, including seasonal larval dispersal and external spatiotemporal forcing. We tested coral sensitivity in 2,083 reefs across the CT region and surrounding areas under potential future temperature regimes, with and without interannual climate variability, exploring a range of 0.5-2.0 degrees C overall increase in temperature in the system by 2054. We found that among future projections, reef survival probability and mean percent coral cover over time were largely determined by the presence or absence of interannual sea surface temperature (SST) extremes as well as absolute temperature increase. Overall, reefs that experienced SST time series that were filtered to remove interannual variability had approximately double the chance of survival than reefs subjected to unfiltered SST. By the end of the forecast period, the inclusion of thermal anomalies was equivalent to an increase of at least 0.5 degrees C in SST projections without anomalies. Change in percent coral cover varied widely across the region within temperature scenarios, with some reefs experiencing local extinction while others remaining relatively unchanged. Sink strength and current thermal stress threshold were found to be significant drivers of these patterns, highlighting the importance of processes that underlie larval connectivity and bleaching sensitivity in coral networks.
  • Educators, not bureaucrats: how managerial professionals at international student services centers engage in job crafting and create meaning in their work

    Castiello-Gutiérrez, Santiago; Hoye, Katie A. R.; García, Hugo A.; McNaughtan, Jon; Univ Arizona, Ctr Study Higher Educ (ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD, 2020-01-26)
    International student services centers (ISSC) at postsecondary institutions in the United States are central to supporting international students' transition and adjustment needs. As leaders of these units, ISSC directors are 'managerial professionals' (MPs), exhibiting characteristics of both traditional academic and administrative roles. These qualities mirror the requisite adaptiveness of their positions, required to navigate the complex international, national, and institutional factors affecting their students and departments. Using Job Crafting Theory, this qualitative study evaluates the experiences of eighteen ISSC directors to explore how, and to what extent, they adapt their jobs in ways related to the creation and integration of meaning. Findings illustrate how participants engaged in cognitive, relational, and task crafting where departmental and institutional goals, students' needs, and personal fulfillment overlapped. The final discussion addresses how institutional leaders, as key partners in successful job crafting, can utilize this framework to support ISSC staff, international students, and promote internationalization.
  • Marketing to International Students: Presentation of University Self in Geopolitical Space

    Rhoades, Gary; Castiello-Gutierrez, Santiago; Lee, Jenny J.; Marei, Mahmoud Sayed; O'Toole, Leslie C.; Univ Arizona, Ctr Study Higher Educ (JOHNS HOPKINS UNIV PRESS, 2019-01-01)
    Amidst public calls for greater internationalization, universities are marketing to international students. We explore how universities in regional hubs (Lee & Schoole, 2015) enact "dramaturgical performances" (Goffman, 1959), presenting images of themselves in geopolitical space. We find: (1) bifurcated marketing strategies to distinct student audiences; (2) differences between public and private universities in featuring lifestyle or academic issues, and higher education as a private or a public good, as in "academic capitalism" (Slaughter & Rhoades, 2004); & (3) distinctive positioning of universities by type and region in their local/national/regional space, highlighting the possibility of alternatives to dominant Anglo-American internationalization models.
  • Photochemical Hazes in Sub-Neptunian Atmospheres with a Focus on GJ 1214b

    Lavvas, Panayotis; Koskinen, Tommi; Steinrueck, Maria E.; García Muñoz, Antonio; Showman, Adam P.; Univ Arizona, Lunar & Planetary Lab (IOP PUBLISHING LTD, 2019-06-20)
    We study the properties of photochemical hazes in super-Earth/mini-Neptune atmospheres with particular focus on GJ 1214b. We evaluate photochemical haze properties at different metallicities between solar and 10,000x.solar. Within the four-order-of-magnitude change in metallicity, we find that the haze precursor mass fluxes change only by a factor of similar to 3. This small diversity occurs with a nonmonotonic manner among the different metallicity cases, reflecting the interaction of the main atmospheric gases with the radiation field. Comparison with relative haze yields at different metallicities from laboratory experiments reveals a qualitative similarity to our theoretical calculations and highlights the contributions of different gas precursors. Our haze simulations demonstrate that higher metallicity results in smaller average particle sizes. Metallicities at and above 100x solar with haze formation yields of similar to 10% provide enough haze opacity to satisfy transit observations at visible wavelengths and obscure sufficiently the H2O molecular absorption features between 1.1 and 1.7 mu m. However, only the highest-metallicity case considered (10,000x.solar) brings the simulated spectra into closer agreement with transit depths at 3.6 and 4.5 mu m, indicating a high contribution of CO/CO2 in GJ 1214b's atmosphere. We also evaluate the impact of aggregate growth in our simulations, in contrast to spherical growth, and find that the two growth modes provide similar transit signatures (for D-f = 2), but with different particle size distributions. Finally, we conclude that the simulated haze particles should have major implications for the atmospheric thermal structure and for the properties of condensation clouds.
  • HALOGAS: the properties of extraplanar HI in disc galaxies

    Marasco, A.; Fraternali, F.; Heald, G.; de Blok, W. J. G.; Oosterloo, T.; Kamphuis, P.; Józsa, G. I. G.; Vargas, C. J.; Winkel, B.; Walterbos, R. A. M.; et al. (EDP SCIENCES S A, 2019-10-17)
    We present a systematic study of the extraplanar gas (EPG) in a sample of 15 nearby late-type galaxies at intermediate inclinations using publicly available, deep interferometric HI data from the Hydrogen Accretion in LOcal GAlaxieS (HALOGAS) survey. For each system we masked the HI emission coming from the regularly rotating disc and used synthetic datacubes to model the leftover "anomalous" HI flux. Our model consists of a smooth, axisymmetric thick component described by three structural and four kinematical parameters, which are fit to the data via a Markov chain Monte Carlo (MCMC) based Bayesian method. We find that extraplanar HI is nearly ubiquitous in disc galaxies as we fail to detect it in only two of the systems with the poorest spatial resolution. The EPG component encloses similar to 5-25% of the total HI mass with a mean value of 14%, and has a typical thickness of a few kpc which is incompatible with expectations based on hydrostatic equilibrium models. The EPG kinematics is remarkably similar throughout the sample, and consists of a lagging rotation with typical vertical gradients of similar to-10 km s(-1) kpc(-1), a velocity dispersion of 15-30 km s(-1), and, for most galaxies, a global inflow in both the vertical and radial directions with speeds of 20-30 km s(-1). The EPG HI masses are in excellent agreement with predictions from simple models of the galactic fountain that are powered by stellar feedback. The combined effect of photo-ionisation and interaction of the fountain material with the circumgalactic medium can qualitatively explain the kinematics of the EPG, but dynamical models of the galactic fountain are required to fully test this framework.
  • H.E.S.S. detection of very high-energy γ-ray emission from the quasar PKS 0736+017

    Smith, P. S.; Univ Arizona, Steward Observ (EDP SCIENCES S A, 2020-01-28)
    Context. Flat-spectrum radio-quasars (FSRQs) are rarely detected at very high energies (E& x2004;>=& x2004;100 GeV) due to their low-frequency-peaked spectral energy distributions. At present, only six FSRQs are known to emit very high-energy (VHE) photons, representing only 7% of the VHE extragalactic catalog, which is largely dominated by high-frequency-peaked BL Lacertae objects. Aims. Following the detection of MeV-GeV gamma-ray flaring activity from the FSRQ PKS 0736+017 (z& x2004;=& x2004;0.189) with Fermi-LAT, the H.E.S.S. array of Cherenkov telescopes triggered target-of-opportunity (ToO) observations on February 18, 2015, with the goal of studying the gamma-ray emission in the VHE band. Methods. H.E.S.S. ToO observations were carried out during the nights of February 18, 19, 21, and 24, 2015. Together with Fermi-LAT, the multi-wavelength coverage of the flare includes Swift observations in soft X-ray and optical-UV bands, and optical monitoring (photometry and spectro-polarimetry) by the Steward Observatory, and the ATOM, the KAIT, and the ASAS-SN telescopes. Results. VHE emission from PKS 0736+017 was detected with H.E.S.S. only during the night of February 19, 2015. Fermi-LAT data indicate the presence of a gamma-ray flare, peaking at the time of the H.E.S.S. detection, with a flux doubling timescale of around six hours. The gamma-ray flare was accompanied by at least a 1 mag brightening of the non-thermal optical continuum. No simultaneous observations at longer wavelengths are available for the night of the H.E.S.S. detection. The gamma-ray observations with H.E.S.S. and Fermi-LAT are used to put constraints on the location of the gamma-ray emitting region during the flare: it is constrained to be just outside the radius of the broad-line region r(BLR) with a bulk Lorentz factor Gamma& x2004;similar or equal to& x2004;20, or at the level of the radius of the dusty torus r(torus) with Gamma& x2004;similar or equal to& x2004;60. Conclusions. PKS 0736+017 is the seventh FSRQ known to emit VHE photons, and at z& x2004;=& x2004;0.189 is the nearest so far. The location of the gamma-ray emitting region during the flare can be tightly constrained thanks to opacity, variability, and collimation arguments.
  • Transmission and reflection features of all-dielectrics metasurfaces with electric and magnetic resonances

    Terekhov, Pavel D.; Babicheva, Viktoriia E.; Baryshnikova, Kseniia V.; Shalin, Alexander S.; Karabchevsky, Alina; Evlyukhin, Andrey B.; Univ Arizona (SPIE-INT SOC OPTICAL ENGINEERING, 2019-03-04)
    The effective multipole decomposition approach is applied to study the optical features of the silicon metasurface in the near-infrared. The spectral regions of perfect transmission and reflection have been analyzed using the Cartesian multipole decomposition. It is shown that transmission peaks appear due to the mutual interaction of multipole moments up to the third order, while reflection peaks are due to the dominant contribution of one of the multipole moments. The results of this work can be broadly applied to design novel metasurfaces, sensors, and optical filters.
  • Lipuite, a new manganese phyllosilicate mineral from the N'Chwaning III mine, Kalahari Manganese Fields, South Africa

    Gu, Xiangping; Yang, Hexiong; Xie, Xiande; van Nieuwenhuizen, Jaco J.; Downs, Robert T.; Evans, Stanley H.; Univ Arizona, Dept Geosci (MINERALOGICAL SOC, 2019-02-26)
    A new phyllosilicate mineral, lipuite (IMA2014-085), has been discovered from the N'Chwaning III mine, Kalahari Manganese Fields, Northern Cape Province, Republic of South Africa. It occurs as platy, tabular, or granular crystals and veined agglomerate in association with Mn-bearing sugilite, taniajacoite, pectolite, richterite, norrishite and namansilite. Lipuite is dark red-brown with vitreous lustre, red streak, an estimated Mohs hardness of 5 and the measured density is 2.83(3) g/cm(3). It is biaxial (+) and characterised by bright red to dark red colour in thin section with measured refractive indices in white light: alpha= 1.635(1), beta= 1.653(1), gamma = 1.670(1) and 2V = 86(2)degrees. The Raman spectra of lipuite are composed of over 21 bands at 109, 146, 162, 183, 206, 244, 288, 342, 362, 455, 496, 520, 552, 613, 669, 886, 930, 971, 1097, 3487 and 3540 cm(-1). The empirical formula from microprobe analyses is (based on total number of cations = 27.5 and structural refinement): K1.12Na8.16(Mn4.77Fe0.07)(Sigma 4)Mg-.(84)0(.44)[Si11.97O30(OH)(4)](PO4)(0.94)O-2(OH)(2 center dot)4H(2)O. The idealised formula is: KNa(8)Mn5(3+)Mg(0.5)Si(12)O(30)(OH)(4)] (PO4)O-2(OH)(2)center dot 4H(2)O. Lipuite is orthorhombic, space group Pnnm, a = 9.080(3), b = 12.222(3), c = 17.093(5) angstrom, V = 1897.0(9) angstrom(3) and Z = 2. The strongest powder X-ray diffraction peaks [d, angstrom (I) (hkl)] are: 9.965(40)(011), 2.938(33)(310), 2.895(100)(311), 2.777(38)(224), 2.713(53)(320), 2.483(32)(126), 2.086(35)(046) and 1.534(40)(446). The crystal structure of lipuite is characterised by sheets of SiO4 tetrahedra that are linked together along [010] by K+, Na+, Mn3+, Mg2+ and P5+ cations, as well as hydrogen bonds. These tetrahedral sheets consist of 14-membered rings of SiO4 tetrahedra that zigzag along [100]. The two independent Mn3+ cations are both octahedrally coordinated. They form five-membered, edge-shared octahedral clusters between the SiO4 tetrahedral sheets. Lipuite represents a rather unique structure type and its silicate tetrahedral sheets can be considered a derivative of the silicate sheets in mica.
  • New insights into ice accumulation at Galena Creek Rock Glacier from radar imaging of its internal structure

    Petersen, Eric Ivan; Levy, Joseph S.; Holt, John W.; Stuurman, Cassie M.; Univ Arizona, Lunar & Planetary Lab (CAMBRIDGE UNIV PRESS, 2019-10-04)
    The ice-cored Galena Creek Rock Glacier, Wyoming, USA, has been the subject of a number of studies that sought to determine the origin of its ice. We present new observations of the rock glacier's internal structure from ground-penetrating radar to constrain ice and debris distribution and accumulation. We imaged dipping reflectors in the center of the glacier that are weak and discontinuous, in contrast to strong reflectors toward the edge of the cirque beneath large debris-avalanche chutes. These reflectors form a network of concave-up, up-glacier dipping layers. We interpret these as englacial debris bands formed by large debris falls buried by subsequent ice and snow accumulation. They are discontinuous where ice outpaces debris accumulation, but with sufficient debris accumulation an interleaved pattern of ice and debris layers can form. We propose a model in which the ice in these interleaved layers is snowfall preserved by debris-facilitated accumulation. Large debris falls that occur in early spring bury sections of the snowpack, which are then preserved through summer and incorporated into the rock glacier body over time. This study highlights the importance of sequential accumulation of ice and debris for understanding the dynamics of rock glaciers and debris-covered glaciers.
  • Probing ISM Structure in Trumpler 14 and Carina I Using the Stratospheric Terahertz Observatory 2

    Seo, Young Min; Goldsmith, Paul F.; Walker, Christopher K.; Hollenbach, David J.; Wolfire, Mark G.; Kulesa, Craig A.; Tolls, Volker; Bernasconi, Pietro N.; Kavak, Ümit; van der Tak, Floris F. S.; et al. (IOP PUBLISHING LTD, 2019-06-20)
    We present observations of the Trumpler 14/Carina I region carried out using the Stratospheric Terahertz Observatory 2. The Trumpler 14/Carina I region is in the western part of the Carina Nebula Complex (CNC), which is one of the most extreme star-forming regions in the Milky Way. We observed Trumpler 14/Carina I in the 58 mu m transition of [C II] with a spatial resolution of 48 '' and a velocity resolution of 0.17 km s(-1). The observations cover a 0 degrees.25 by 0 degrees.28 area with central position l = 297 degrees.34, b = -0 degrees.60. The kinematics show that bright [C II] structures are spatially and spectrally correlated with the surfaces of CO clouds, tracing the photodissociation region (PDR) and ionization front of each molecular cloud. Along seven lines of sight (LOSs) that traverse Tr 14 into the dark ridge to the southwest, we find that the [C II] luminosity from the H II region is 3.7 times that from the PDR. In the same LOS, we find in the PDRs an average ratio of 1 : 4.1 : 5.6 for the mass in atomic gas : dark CO gas : molecular gas traced by CO. Comparing multiple gas tracers, including H I 21 cm, [C II], CO, and radio recombination lines, we find that the H II regions of the CNC are well described as H II regions with one side freely expanding toward us, consistent with the Champagne model of ionized gas evolution. The dispersal of the GMC in this region is dominated by EUV photoevaporation; the dispersal timescale is 20-30 Myr.
  • Seasonal and synoptic climatic drivers of tree growth in the Bighorn Mountains, WY, USA (1654–1983 CE)

    Hudson, Amy R.; Alfaro-Sanchez, Raquel; Babst, Flurin; Belmecheri, Soumaya; Moore, David J.P.; Trouet, Valerie; Univ Arizona, Sch Nat Resources & Environm; Univ Arizona, Lab Tree Ring Res (ELSEVIER GMBH, 2019-12)
    In the United States' (US) Northern Rockies, synoptic pressure systems and atmospheric circulation drive interannual variation in seasonal temperature and precipitation. The radial growth of high-elevation trees in this semi-arid region captures this temperature and precipitation variability and provides long time series to contextualize instrumental-era variability in synoptic-scale climate patterns. Such variability in climate patterns can trigger extreme climate events, such as droughts, floods, and forest fires, which have a damaging impact on human and natural systems. We developed 11 tree-ring width (TRW) chronologies from multiple species and sites to investigate the seasonal climatic drivers of tree growth in the Bighorn Mountains, WY. A principal component analysis of the chronologies identified 54% of shared common variance (1894-2014). Tree growth (expressed by PC1) was driven by multiple seasonal climate variables: previous October and current July temperatures, as well as previous December and current April precipitation, had a positive influence on growth, whereas growth was limited by July precipitation. These seasonal growth-climate relationships corresponded to circulation patterns at higher atmospheric levels over the Bighorn Mountains. Tree growth was enhanced when the winter jet stream was in a northward position, which led to warmer winters, and when the spring jet stream was further south, which led to wetter springs. The second principal component, explaining 19% of the variance, clustered sites by elevation and was strongly related to summer temperature. We leverage this summer temperature signal in our TRW chronologies by combining it with an existing maximum latewood density (MXD) chronology in a nested approach. This allowed us to reconstruct Bighorn Mountains summer (June, July, and August) temperature (BMST) back to 1654, thus extending the instrumental temperature record by 250 years. Our BMST reconstruction explains 39-53% of the variance in regional summer temperature variability. The 1830s were the relatively coolest decade and the 1930s were the warmest decade over the reconstructed period (1654-1983 CE) - which excludes the most recent 3 decades. Our results contextualize recent drivers and trends of climate variability in the US Northern Rockies, which contributes to the information that managers of human and natural systems need in order to prepare for potential future variability.
  • Do board gender quotas affect firm value? Evidence from California Senate Bill No. 826

    Greene, Daniel; Intintoli, Vincent J.; Kahle, Kathleen M.; Univ Arizona (ELSEVIER, 2020-02)
    We examine stock market reactions, direct costs of compliance, and board adjustments to California Senate Bill No. 826 (SB 826), the first mandated board gender diversity quota in the United States. Announcement returns average -1.2% and are robust to the use of multiple methodologies. Returns are more negative when the gap between the mandated number and the pre-SB 826 number of female directors is larger. These negative effects are less severe for firms with a greater supply of female candidates, and for those that can more easily replace male directors or attract female directors. For small firms, the annual direct cost of compliance through board expansion is non-trivial, representing 0.76% of market value. Following SB 826, firms significantly increase female board representation, and the increase is greater for firms in California than control firms in other states.
  • Propagation in a Fisher-KPP equation with non-local advection

    Hamel, François; Henderson, Christopher; Univ Arizona, Dept Math (ACADEMIC PRESS INC ELSEVIER SCIENCE, 2020-04-15)
    We investigate the influence of a general non-local advection term of the form K *u to propagation in the one-dimensional Fisher-KPP equation. This model is a generalization of the Keller-Segel-Fisher system. When K is an element of L-1(R), we obtain explicit upper and lower bounds on the propagation speed which are asymptotically sharp and more precise than previous works. When K is an element of L-P(R) with p > 1 and is non-increasing in (-infinity, 0) and in (0, +infinity), we show that the position of the "front" is of order 0(t(p)) if p < infinity and O(e(lambda t)) for some lambda > 0 if p = infinity and K(+infinity) > 0. We use a wide range of techniques in our proofs. (C) 2019 Elsevier Inc. All rights reserved.
  • The Bramson delay in the non-local Fisher-KPP equation

    Bouin, Emeric; Henderson, Christopher; Ryzhik, Lenya; Univ Arizona, Dept Math (ELSEVIER, 2020-01-01)
    We consider the non-local Fisher-KPP equation modeling a population with individuals competing with each other for resources with a strength related to their distance, and obtain the asymptotics for the position of the invasion front starting from a localized population. Depending on the behavior of the competition kernel at infinity, the location of the front is either 2t - (3/2) log t + O(1), as in the local case, or 2t - O(t(beta)) for some explicit beta is an element of (0, 1). Our main tools here are a local-in-time Harnack inequality and an analysis of the linearized problem with a suitable moving Dirichlet boundary condition. Our analysis also yields, for any beta is an element of (0, 1), examples of Fisher-KPP type non-linearities f(beta) such that the front for the local Fisher-KPP equation with reaction term f(beta) is at 2t - O(t(beta)). (C) 2019 Published by Elsevier Masson SAS.
  • Dynamic changes in dissolved organic matter composition in a Mountain Lake under ice cover and relationships to changes in nutrient cycling and phytoplankton community composition

    Rue, Garrett P.; Darling, Joshua P.; Graham, Emily; Tfaily, Malak M.; McKnight, Diane M.; Univ Arizona, Dept Soil Water & Environm Sci (SPRINGER BASEL AG, 2019-12-17)
    We studied Bear Lake, a subalpine oligotrophic lake in Rocky Mountain National Park, Colorado USA, during the winter ice cover period of 2018. Our goal was to understand relationships between biogeochemical and biotic processes and the chemical quality of the dissolved organic matter (DOM), a major pool of organic carbon in all lakes. The lake was stratified with limited light availability and had a consistent oxycline at 7 m. Nutrient concentrations were low and the depletion of nitrogen species was related to increased phytoplankton abundance. The phytoplankton community became progressively dominated by a potentially mixotrophic dinoflagellate species, Gymnodinium sp., and a deep chlorophyll maximum developed above the hypolimnion. Changes in the chemical quality of DOM, as measured through high-resolution mass spectrometry, were associated with these shifts in nutrient and phytoplankton composition. The spectrometry data revealed a pool of organic compounds many of which contained phosphorus, nitrogen, and sulfur. This pool evolved through the winter, with phosphorus-containing compounds becoming more predominant in the upper oxic zone and sulfur-containing compounds becoming more predominant in the anoxic bottom waters. Reduced chemo diversity of the DOM pool in the surface waters developed through the winter. In the bottom waters, more unique compounds were produced through the winter, and the favorability of the DOM to support microbial respiration also increased. These observed differences in DOM molecular composition were not reflected in the spectroscopic signature of the DOM pool. Overall, our results show chemical changes in the DOM pool correlate to dynamic redox conditions, biogeochemical cycling, and biotic response to ice cover.
  • Environmentally relevant exposure to dibutyl phthalate disrupts DNA damage repair gene expression in the mouse ovary†

    Liu, Xiaosong; Craig, Zelieann R; Univ Arizona, BIO5 Inst; Univ Arizona, Sch Anim & Comparat Biomed Sci, Shantz Room (OXFORD UNIV PRESS INC, 2019-10-04)
    Phthalates have a history of reproductive toxicity in animal models and associations with adverse reproductive outcomes in women. Human exposure to dibutyl phthalate (DBP) occurs via consumer products (7-10 mu g/kg/day) and medications (1-233 mu g/kg/day). Most DBP toxicity studies have focused on high supraphysiological exposure levels; thus, very little is known about exposures occurring at environmentally relevant levels. CD-1 female mice (80 days old) were treated with tocopherol-stripped corn oil (vehicle control) or DBP dissolved in oil at environmentally relevant (10 and 100 mu g/kg/day) or higher (1000 mu g/kg/day) levels for 30 days to evaluate effects on DNA damage response (DDR) pathway genes and folliculogenesis. DBP exposure caused dose-dependent effects on folliculogenesis and gene expression. Specifically, animals exposed to the high dose of DBP had more atretic follicles in their ovaries, while in those treated with environmentally relevant doses, follicle numbers were no different from vehicle-treated controls. DBP exposure significantly reduced the expression of DDR genes including those involved in homologous recombination (Atm, Brca1, Mre11a, Rad50), mismatch repair (Msh3, Msh6), and nucleotide excision repair (Xpc, Pcna) in a dose-specific manner. Interestingly, staining for the DNA damage marker, gamma H2AX, was similar between treatments. DBP exposure did not result in differential DNA methylation in the Brca1 promoter but significantly reduced transcript levels for the maintenance DNA methyltransferase, Dnmt1, in the ovary. Collectively, these findings show that oral exposure to environmentally relevant levels of DBP for 30 days does not significantly impact folliculogenesis in adult mice but leads to aberrant ovarian expression of DDR genes. Summary Sentence Exposure to human relevant doses of dibutyl phthalate results in significant disruption of DNA damage repair gene expression in the mouse ovary.
  • Multi-beam Transmissions for Blockage Resilience and Reliability in Millimeter-Wave Systems

    Aykin, Irmak; Akgun, Berk; Krunz, Marwan; Univ Arizona, Dept Elect & Comp Engn (IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 2019-10-21)
    Directionality in millimeter-wave (mmW) systems make link establishment and maintenance challenging, due to the search-time overhead of beam scanning and the vulnerability of directional links to blockages. In this paper, we propose a communication protocol called SmartLink, which exploits the clustering phenomenon at mmW frequencies to establish a multi-beam link between a base station and a user. By utilizing multiple clusters, SmartLink enables efficient link maintenance and sustained throughput. We develop a logarithmic-time search algorithm called multi-lobe beam search (MLBS), which is used in SmartLink to discover the clusters. MLBS probes several directions simultaneously, using multi-lobe beam patterns. The number of simultaneous lobes is selected to minimize the search time of the clusters. We provide detailed analysis of the false alarm and misdetection probabilities for the designed beam patterns. Following cluster discovery, SmartLink divides antennas into sub-arrays to generate the optimal multi-lobe beam pattern that maximizes the average data rate under blockage. Extensive simulations using actual channel traces obtained by utilizing phased-array antennas at 29 GHz are used to verify the efficiency of SmartLink. MLBS decreases the discovery time by up to 88 compared to common existing search schemes, and exploiting multiple clusters improves the average data rate by 10.
  • A post-processing scheme for the performance improvement of vehicle detection in wide-area aerial imagery

    Gao, Xin; Univ Arizona, Dept Elect & Comp Engn (SPRINGER LONDON LTD, 2019-11-08)
    In this paper, we present a post-processing scheme to improve the performance of vehicle detection in wide-area aerial imagery. Using low-resolution aerial frames for the performance analysis, we adapted nine algorithms for vehicle detection. We derived a three-stage scheme to measure performance improvement on the selected five object segmentation algorithms before and after post-processing. We compared automatic detections results to ground-truth objects, and classified each type of detections in terms of true positive, false negative and false positive. Several evaluation metrics are adopted for the experimental study.
  • Clinical features of cats diagnosed with coccidioidomycosis in Arizona, 2004 - 2018

    Arbona, Nichole; Butkiewicz, Christine; Keyes, Minta; Shubitz, Lisa; Univ Arizona, Valley Fever Ctr Excellence (SAGE, 2020-02)
    Objectives: The goal of this study was to describe the clinical presentation, diagnosis and treatment of coccidioidomycosis in cats residing in a region endemic for Coccidioides species. Methods: A retrospective review of records was performed at both primary and tertiary care veterinary practices in Tucson and Phoenix, AZ. Data collected included signalment, clinical signs, physical exam findings, diagnostic test results, treatment and outcome. Results: Fifty-one feline cases were identified from six different veterinary hospitals. Cats presented with clinical signs and laboratory abnormalities similar to what has been seen in dogs, including respiratory illness (20/51), neutrophilia (24/31), monocytosis (17/31), and hyperglobulinemia (16/30). However, cats at diagnosis were typically significantly ill, with 31/51 having disseminated infection, most commonly to the skin (n=22). Additionally, 43/44 cats that had serum antibody tests performed were positive, and median titer at diagnosis was 1:32 (range 1:4 – ≥1:256). Serum antibody titers reduced significantly (P ≤0.001) in cats that responded to treatment compared with cats that did not clinically improve. 40/46 cats that were treated with oral flucaonzole responded and did not require additional therapy. Fourteen cats developed recurrent disease and all but 1 had antifungal therapy successfully reinstituted. Conclusions and relevance: Coccidioidomycosis is a disease of concern for cats residing in the region endemic for Coccidoides spp. Disease is most often disseminated at the time of diagnosis, possibly due to delays in presentation for care and recognition of the infection. Suspicion of disease, serum chemistries, blood cell counts, presence of antibody, and imaging aid in diagnosis of coccidioidomycosis in cats. Serum antibody reduction during treatment frequently correlated with an adequate response to medication. Consideration of coccidioidomycosis as a cause of illness will lead to earlier diagnosis and potentially better treatment outcomes in cats.  
  • PUENTES Program: An Institutional Response Claiming for Bridges in a Time of Trumpeting Walls

    Castiello-Gutiérrez, Santiago; Camacho Lizárraga, Mónica Irene; Univ Arizona, Ctr Study Higher Educ (Springer Singapore, 2020-02-15)
    Following the 2016 U.S. presidential election and the government openly anti-immigrant rhetoric threatening to deport unauthorized immigrants (including students with DACA protection), several actors in Mexico organized to launch the PUENTES program to facilitate enrollment of Mexican students living in the U.S. at a Mexican HEI to finish their degrees. In this chapter we analyze, from a policy perspective, how a country can prepare to serve their once migrant citizens, now returning students, who need to be re-enrolled into the higher education system and therefore into the society. Key findings suggest that the program has been successful in the following ways: (1) It has provided visibility to the issue of forced migration back to Mexico; (2) It helped to expedite changes in legislation that now make it easier for anyone with partial studies outside Mexico to continue with their education in an HEI in the country; and (3) It provided an alternative, not only to students who faced deportation but also to those who willingly saw an opportunity to continue with their studies at an institution in their place of birth.

View more