Kamenetzky, J. R.; Rangwala, N.; Glenn, J.; Maloney, P. R.; Conley, A.; Univ Arizona, Steward Observ (IOP PUBLISHING LTD, 2016-09-26)
      We present a catalog of all CO (J = 4-3 through J = 13-12), [ C I], and [ N II] lines available from extragalactic spectra from the Herschel SPIRE Fourier Transform Spectrometer (FTS) archive combined with observations of the low-J CO lines from the literature and from the Arizona Radio Observatory. This work examines the relationships between L-FIR, L'(CO), and L-CO/L-CO,L-1-0. We also present a new method for estimating probability distribution functions from marginal signal-to-noise ratio Herschel FTS spectra, which takes into account the instrumental "ringing" and the resulting highly correlated nature of the spectra. The slopes of log(L-FIR) versus log (L'(CO)) are linear for all mid- to high-J CO lines and slightly sublinear if restricted to (ultra) luminous infrared galaxies ((U) LIRGs). The mid-to high-J CO luminosity relative to CO J - 1-0 increases with increasing L-FIR, indicating higher excitement of the molecular gas, although these ratios do not exceed similar to 180. For a given bin in L-FIR, the luminosities relative to CO J = 1-0 remain relatively flat from J = 6-5 through J = 13-12, across three orders of magnitude of L-FIR. A single component theoretical photodissociation region (PDR) model cannot match these flat SLED shapes, although combinations of PDR models with mechanical heating added qualitatively match the shapes, indicating the need for further comprehensive modeling of the excitation processes of warm molecular gas in nearby galaxies.

      Stone, Jordan M.; Eisner, Josh A.; Skemer, Andrew J.; Morzinski, Katie M.; Close, Laird M.; Males, Jared R.; Rodigas, Timothy J.; Hinz, Phil; Puglisi, Alfio; Univ Arizona, Steward Observ (IOP PUBLISHING LTD, 2016-09-21)
      L-band spectroscopy is a powerful probe of cool low-gravity atmospheres: the P, Q, and R branch fundamental transitions of methane near 3.3 mu m provide a sensitive probe of carbon chemistry; cloud thickness modifies the spectral slope across the band; and H-3(+) opacity can be used to detect aurorae. Many directly imaged gas-giant companions to nearby young stars exhibit L-band fluxes distinct from the field population of brown dwarfs at the same effective temperature. Here we describe commissioning the L-band spectroscopic mode of Clio2, the 1-5 mu m instrument behind the Magellan adaptive-optics system. We use this system to measure L-band spectra of directly imaged companions. Our spectra are generally consistent with the parameters derived from previous near-infrared spectra for these late M to early L type objects. Therefore, deviations from the field sequence are constrained to occur below 1500 K. This range includes the L-T transition for field objects and suggests that observed discrepancies are due to differences in cloud structure and CO/CH4 chemistry.
    • La Vida Buena (The Good Life) evaluation: a quasi experimental intervention of a community health worker-led family-based childhood obesity program for Latino children 5-8 years of age on the US-Mexico border

      Tucker, Kathryn M; Ingram, Maia; Doubleday, Kevin; Piper, Rosie; Carvajal, Scott C; Univ Arizona, Prevent Res Ctr (BMC, 2019-06-14)
      Background: Due to multiple and interacting factors, Latino children are disproportionately at risk for overweight and obesity in the United States. Childhood obesity increases the risk for adverse physical and psychosocial outcomes throughout the lifespan. Intensive behavioral interventions recommended in primary care settings may not conform to current practices, and the most vulnerable populations are often unable to access these services. Community Health Workers (CHWs) offer a promising approach to bridging the gap between vulnerable communities and culturally competent services. La Vida Buena (The Good Life) is an 8-week family-focused intervention for Latino children 5-8years old and their parents or caregivers who are patients at a Federally-Qualified Community Health Center (FQHC). It is a culturally and linguistically appropriate curriculum, facilitated by CHWs, that targets family behaviors to foster a healthy lifestyle in order to prevent and mitigate childhood overweight and obesity. Methods: The primary objective is to test the effectiveness of the La Vida Buena (LVB) childhood obesity program among Latino children 5-8years old and their families as compared with a single educational session. This study uses a parallel two-arm quasi-experimental design. The intervention group receives the 8-week La Vida Buena intervention and the comparison group receives a single educational session. The primary outcome is the change in the child's BMI z-score from baseline to 6 months. Discussion: The implementation and evaluation of La Vida Buena may inform research and practice for linking Latino patients in FQHCs to culturally responsive community-based childhood obesity interventions. It will also contribute to the literature about CHWs as facilitators of behavior change for families underserved by health services and preventive programs. La Vida Buena can serve as a culturally and linguistically appropriate early intervention curriculum that will foster a healthy home environment for childhood obesity mitigation and prevention. Trial registration: The trial was retrospectively registered on December 18, 2018. The ClinicalTrials.gov Identifier is NCT03781856.
    • Label-free Mie Scattering Identification of Tumor Tissue Using an Angular Photodiode Array

      Bills, Matthew V; Yoon, Jeong-Yeol; Univ Arizona, Dept Biomed Engn (IEEE, 2020)
      Tumors differ from normal tissues in several meaningful ways, including cellular size, morphology, and protein expression, which will accordingly change the refractive index and the size/morphology of cells. There are also important differences in the tissue organization and unique tissue-specific cell densities. Instead of the time-consuming and labor-intensive histology involving the use of a benchtop microscope, a plot of Mie scattering intensities at a fixed wavelength against the scattering angle, which we referred to as “Mie spectrum,” is suggested as an alternative to identify a tumor from normal tissues. An angular photodiode array is developed to measure this Mie spectrum with three different light-emitting diodes (blue, green, and red) as light sources. The resulting Mie spectra show the characteristic peaks for the rat colonic tissues, and substantial differences can be found between the tumor and normal tissues. Two peaks were identified at 120° and 150° scattering angles, potentially representing the capillaries and colon cells, respectively. Contributions from crypts and goblet cells, represented by the scattering at 140°, were minimal. Substantial differences between the tumor and normal tissues were found with 45°–70° light irradiation angles.
    • A labor day warning

      Robbins, Richard A.; The University of Arizona College of Medicine - Phoenix (Arizona Thoracic Society, 2018-09-03)
    • Lack of aggression and apparent altruism towards intruders in a primitive termite

      Cooney, Feargus; Vitikainen, Emma I. K.; Marshall, Harry H.; van Rooyen, Wilmie; Smith, Robert L.; Cant, Michael A.; Goodey, Nicole; Univ Arizona, Dept Entomol (ROYAL SOC, 2016-11-09)
      In eusocial insects, the ability to discriminate nest-mates from non-nest-mates is widespread and ensures that altruistic actions are directed towards kin and agonistic actions are directed towards non-relatives. Most tests of nest-mate recognition have focused on hymenopterans, and suggest that cooperation typically evolves in tandem with strong antagonism towards non-nest-mates. Here, we present evidence from a phylogenetically and behaviourally basal termite species that workers discriminate members of foreign colonies. However, contrary to our expectations, foreign intruders were the recipients of more rather than less cooperative behaviour and were not subjected to elevated aggression. We suggest that relationships between groups may be much more peaceable in basal termites compared with eusocial hymenoptera, owing to energetic and temporal constraints on colony growth, and the reduced incentive that totipotent workers (who may inherit breeding status) have to contribute to self-sacrificial intergroup conflict.
    • Lagged response of tropical tropospheric temperature to solar ultraviolet variations on intraseasonal time scales

      Hood, L. L.; Univ Arizona, Lunar & Planetary Lab; Lunar and Planetary Laboratory; University of Arizona; Tucson Arizona USA (AMER GEOPHYSICAL UNION, 2016-04-28)
      Correlative and regression analyses of daily ERA-Interim reanalysis data for three separate solarmaximum periods confirm the existence of a temperature response to short-term (mainly ∼27 day) solarultraviolet variations at tropical latitudes in both the lower stratosphere and troposphere. The response,which occurs at a phase lag of 6–10 days after the solar forcing peak, consists of a warming in the lowerstratosphere, consistent with relative downwelling and a slowing of the mean meridional (Brewer-Dobson)circulation, and a cooling in the troposphere. The midtropospheric cooling response is most significant inthe tropical Pacific, especially under positive El Niño–Southern Oscillation conditions and may be relatedto a reduction in the number of Madden-Julian oscillation events that propagate eastward into the centralPacific following peaks in short-term solar forcing.
    • Lagged response of tropical tropospheric temperature to solar ultraviolet variations on intraseasonal time scales

      Hood, L. L.; Univ Arizona, Lunar & Planetary Lab (AMER GEOPHYSICAL UNION, 2016-04-28)
      Correlative and regression analyses of daily ERA-Interim reanalysis data for three separate solar maximum periods confirm the existence of a temperature response to short-term (mainly similar to 27 day) solar ultraviolet variations at tropical latitudes in both the lower stratosphere and troposphere. The response, which occurs at a phase lag of 6-10 days after the solar forcing peak, consists of a warming in the lower stratosphere, consistent with relative downwelling and a slowing of the mean meridional (Brewer-Dobson) circulation, and a cooling in the troposphere. The midtropospheric cooling response is most significant in the tropical Pacific, especially under positive El Nino-Southern Oscillation conditions and may be related to a reduction in the number of Madden-Julian oscillation events that propagate eastward into the central Pacific following peaks in short-term solar forcing.
    • Lambda(c) -> Lambda l(+)nu(l) Form Factors and Decay Rates from Lattice QCD with Physical Quark Masses

      Meinel, Stefan; Univ Arizona, Dept Phys (AMER PHYSICAL SOC, 2017-02-21)
      The first lattice QCD calculation of the form factors governing Lambda(c) -> Lambda l(+)nu(l) decays is reported. The calculation was performed with two different lattice spacings and includes one ensemble with a pion mass of 139(2) MeV. The resulting predictions for the Lambda(c) -> Lambda e(+)nu(e) and Lambda(c) -> Lambda mu(+)nu(mu) decay rates divided by vertical bar V-cs vertical bar(2) are 0.2007(71)(74) and 0.1945(69)(72) p(s-1), respectively, where the two uncertainties are statistical and systematic. Taking the Cabibbo-Kobayashi-Maskawa (CKM) matrix element vertical bar V-cs vertical bar from a global fit and the Lambda(c) lifetime from experiments, this translates to branching fractions of B(Lambda(c) -> Lambda e(e)(+nu)) = 0.0380(19)(LQCD)(11)(tau Lambda c) and B(Lambda(c) -> Lambda mu(+)nu(mu)) 0.0369(19)(LQCD)(11)(tau Lambda c). These results are consistent with, and two times more precise than, the measurements performed recently by the BESIII Collaboration. Using instead the measured branching fractions together with the lattice calculation to determine the CKM matrix element gives vertical bar V-cs vertical bar = 0.949(24)(LQCD)(14)(tau)Lambda c (49)(B).
    • Laminin 521 maintains differentiation potential of mouse and human satellite cell-derived myoblasts during long-term culture expansion

      Penton, Christopher M.; Badarinarayana, Vasudeo; Prisco, Joy; Powers, Elaine; Pincus, Mark; Allen, Ronald E.; August, Paul R.; Univ Arizona, Sch Anim & Comparat Biomed Sci (BIOMED CENTRAL LTD, 2016-12-13)
      Background: Large-scale expansion of myogenic progenitors is necessary to support the development of high-throughput cellular assays in vitro and to advance genetic engineering approaches necessary to develop cellular therapies for rare muscle diseases. However, optimization has not been performed in order to maintain the differentiation capacity of myogenic cells undergoing long-term cell culture. Multiple extracellular matrices have been utilized for myogenic cell studies, but it remains unclear how different matrices influence long-term myogenic activity in culture. To address this challenge, we have evaluated multiple extracellular matrices in myogenic studies over long-term expansion. Methods: We evaluated the consequence of propagating mouse and human myogenic stem cell progenitors on various extracellular matrices to determine if they could enhance long-term myogenic potential. For the first time reported, we comprehensively examine the effect of physiologically relevant laminins, laminin 211 and laminin 521, compared to traditionally utilized ECMs (e.g., laminin 111, gelatin, and Matrigel) to assess their capacity to preserve myogenic differentiation potential. Results: Laminin 521 supported increased proliferation in early phases of expansion and was the only substrate facilitating high-level fusion following eight passages in mouse myoblast cell cultures. In human myoblast cell cultures, laminin 521 supported increased proliferation during expansion and superior differentiation with myotube hypertrophy. Counterintuitively however, laminin 211, the native laminin isoform in resting skeletal muscle, resulted in low proliferation and poor differentiation in mouse and human cultures. Matrigel performed excellent in short-term mouse studies but showed high amounts of variability following long-term expansion. Conclusions: These results demonstrate laminin 521 is a superior substrate for both short-term and long-term myogenic cell culture applications compared to other commonly utilized substrates. Since Matrigel cannot be used for clinical applications, we propose that laminin 521 could possibly be employed in the future to provide myoblasts for cellular therapy directed clinical studies.
    • Laminin-332 alters connexin profile, dye coupling and intercellular Ca2+ waves in ciliated tracheal epithelial cells

      Isakson, Brant; Olsen, Colin; Boitano, Scott; Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, University of Virginia Charlottesville, Virginia 22908, USA; Robert M. Berne Cardiovascular Research Center, University of Virginia School of Medicine, University of Virginia, Charlottesville, Virginia 22908, USA; Arizona Respiratory Center, Arizona Health Sciences Center, University of Arizona, Tucson, Arizona 85724, USA; Department of Physiology, Arizona Health Sciences Center, University of Arizona, Tucson, Arizona 85724, USA (BioMed Central, 2006)
      BACKGROUND:Tracheal epithelial cells are anchored to a dynamic basement membrane that contains a variety of extracellular matrix proteins including collagens and laminins. During development, wound repair and disease of the airway epithelium, significant changes in extracellular matrix proteins may directly affect cell migration, differentiation and events mediated by intercellular communication. We hypothesized that alterations in cell matrix, specifically type I collagen and laminin alpha3beta3gamma2 (LM-332) proteins within the matrix, directly affect intercellular communication in ciliated rabbit tracheal epithelial cells (RTEC).METHODS:Functional coupling of RTEC was monitored by microinjection of the negatively charged fluorescent dyes, Lucifer Yellow and Alexa 350, into ciliated RTEC grown on either a LM-332/collagen or collagen matrix. Coupling of physiologically significant molecules was evaluated by the mechanism and extent of propagated intercellular Ca2+ waves. Expression of connexin (Cx) mRNA and proteins were assayed by reverse transcriptase - polymerase chain reaction and immunocytochemistry, respectively.RESULTS:When compared to RTEC grown on collagen alone, RTEC grown on LM-332/collagen displayed a significant increase in dye transfer. Although mechanical stimulation of RTEC grown on either LM-332/collagen or collagen alone resulted in intercellular Ca2+ waves, the mechanism of transfer was dependent on matrix: RTEC grown on LM-332/collagen propagated Ca2+waves via extracellular purinergic signaling whereas RTEC grown on collagen used gap junctions. Comparison of RTEC grown on collagen or LM-332/collagen matrices revealed a reorganization of Cx26, Cx43 and Cx46 proteins.CONCLUSION:Alterations in airway basement membrane proteins such as LM-332 can induce connexin reorganizations and result in altered cellular communication mechanisms that could contribute to airway tissue function.
    • Laminin-binding integrin gene copy number alterations in distinct epithelial-type cancers.

      Harryman, William L; Pond, Erika; Singh, Parminder; Little, Andrew S; Eschbacher, Jennifer M; Nagle, Raymond B; Cress, Anne E; Univ Arizona, Ctr Canc (E-CENTURY PUBLISHING CORP, 2016)
      The laminin-binding integrin (LBI) family are cell adhesion molecules that are essential for invasion and metastasis of human epithelial cancers and cell adhesion mediated drug resistance. We investigated whether copy number alteration (CNA) or mutations of a five-gene signature (ITGB4, ITGA3, LAMB3, PLEC, and SYNE3), representing essential genes for LBI adhesion, would correlate with patient outcomes within human epithelial-type tumor data sets currently available in an open access format.
    • Laminin-binding integrin gene copy number alterations in distinct epithelial-type cancers.

      Harryman, William L; Pond, Erika; Singh, Parminder; Little, Andrew S; Eschbacher, Jennifer M; Nagle, Raymond B; Cress, Anne E; The University of Arizona Cancer Center, 1515 N. Campbell Ave., Tucson, Arizona, United States (e-Century Publishing, 2016-01-01)
      The laminin-binding integrin (LBI) family are cell adhesion molecules that are essential for invasion and metastasis of human epithelial cancers and cell adhesion mediated drug resistance. We investigated whether copy number alteration (CNA) or mutations of a five-gene signature (ITGB4, ITGA3, LAMB3, PLEC, and SYNE3), representing essential genes for LBI adhesion, would correlate with patient outcomes within human epithelial-type tumor data sets currently available in an open access format. We investigated the relative alteration frequency of an LBI signature panel (integrin β4 (ITGB4), integrin α3 (ITGA3), laminin β3 chain (LAMB3), plectin (PLEC), and nesprin 3 (SYNE3)), independent of the epithelial cancer type, within publically available and published data using cBioPortal and Oncomine software. We rank ordered the results using a 20% alteration frequency cut-off and limited the analysis to studies containing at least 100 samples. Kaplan-Meier survival curves were analyzed to determine if alterations in the LBI signature correlated with patient survival. The Oncomine data mining tool was used to compare the heat map expression of the LBI signature without SYNE3 (as this was not included in the Oncomine database) to drug resistance patterns. Twelve different cancer types, representing 5,647 samples, contained at least a 20% alteration frequency of the five-gene LBI signature. The frequency of alteration ranged from 38.3% to 19.8%. Within the LBI signature, PLEC was the most commonly altered followed by LAMB3, ITGB4, ITGA3, and SYNE3 across all twelve cancer types. Within cancer types, there was little overlap of the individual amplified genes from each sample, suggesting different specific amplicons may alter the LBI adhesion structures. Of the twelve cancer types, overall survival was altered by CNA presence in bladder urothelial carcinoma (p=0.0143*) and cervical squamous cell carcinoma and endocervical adenocarcinoma (p=0.0432*). Querying the in vitro drug resistance profiles with the LBI signature demonstrated a positive correlation with cells resistant to inhibitors of HDAC (Vorinostat, Panobinostat) and topoisomerase II (Irinotecan). No correlation was found with the following agents: Bleomycin, Doxorubicin, Methotrexate, Gemcitabine, Docetaxel, Bortezomib, and Shikonen. Our work has identified epithelial-types of human cancer that have significant CNA in our selected five-gene signature, which was based on the essential and genetically-defined functions of the protein product networks (in this case, the LBI axis). CNA of the gene signature not only predicted overall survival in bladder, cervical, and endocervical adenocarcinoma but also response to chemotherapy. This work suggests that future studies designed to optimize the gene signature are warranted.
    • Land Surface Climate in the Regional Arctic System Model

      Hamman, Joseph; Nijssen, Bart; Brunke, Michael; Cassano, John; Craig, Anthony; DuVivier, Alice; Hughes, Mimi; Lettenmaier, Dennis P.; Maslowski, Wieslaw; Osinski, Robert; et al. (AMER METEOROLOGICAL SOC, 2016-09)
      The Regional Arctic System Model (RASM) is a fully coupled, regional Earth system model applied over the pan-Arctic domain. This paper discusses the implementation of the Variable Infiltration Capacity land surface model (VIC) in RASM and evaluates the ability of RASM, version 1.0, to capture key features of the land surface climate and hydrologic cycle for the period 1979-2014 in comparison with uncoupled VIC simulations, reanalysis datasets, satellite measurements, and in situ observations. RASM reproduces the dominant features of the land surface climatology in the Arctic, such as the amount and regional distribution of precipitation, the partitioning of precipitation between runoff and evapotranspiration, the effects of snow on the water and energy balance, and the differences in turbulent fluxes between the tundra and taiga biomes. Surface air temperature biases in RASM, compared to reanalysis datasets ERA-Interim and MERRA, are generally less than 2 degrees C; however, in the cold seasons there are local biases that exceed 6 degrees C. Compared to satellite observations, RASM captures the annual cycle of snow-covered area well, although melt progresses about two weeks faster than observations in the late spring at high latitudes. With respect to derived fluxes, such as latent heat or runoff, RASM is shown to have similar performance statistics as ERA-Interim while differing substantially from MERRA, which consistently overestimates the evaporative flux across the Arctic region.
    • Landslides on Ceres: Diversity and Geologic Context

      Duarte, K. D.; Schmidt, B. E.; Chilton, H. T.; Hughson, K. H. G.; Sizemore, H. G.; Ferrier, K. L.; Buffo, J. J.; Scully, J. E. C.; Nathues, A.; Platz, T.; et al. (AMER GEOPHYSICAL UNION, 2019-12-17)
      Landslides are among the most widespread geologic features on Ceres. Using data from Dawn's Framing Camera, landslides were previously classified based upon geomorphologic characteristics into one of three archetypal categories, Type 1(T1), Type 2 (T2), and Type 3 (T3). Due to their geologic context, variation in age, and physical characteristics, most landslides on Ceres are, however, intermediate in their morphology and physical properties between the archetypes of each landslide class. Here we describe the varied morphology of individual intermediate landslides, identify geologic controls that contribute to this variation, and provide first‐order quantification of the physical properties of the continuum of Ceres's surface flows. These intermediate flows appear in varied settings and show a range of characteristics, including those found at contacts between craters, those having multiple trunks or lobes; showing characteristics of both T2 and T3 landslides; material slumping on crater rims; very small, ejecta‐like flows; and those appearing inside of catenae. We suggest that while their morphologies can vary, the distribution and mechanical properties of intermediate landslides do not differ significantly from that of archetypal landslides, confirming a link between landslides and subsurface ice. We also find that most intermediate landslides are similar to Type 2 landslides and formed by shallow failure. Clusters of these features suggest ice enhancement near Juling, Kupalo and Urvara craters. Since the majority of Ceres's landslides fall in the intermediate landslide category, placing their attributes in context contributes to a better understanding of Ceres's shallow subsurface and the nature of ground ice.
    • Language dominance and the perception of the Majorcan Catalan /ʎ/−/ʒ/ contrast: Asymmetrical phonological representations

      Ramírez, Marta; Simonet, Miquel; Univ Arizona, Dept Spanish & Portuguese (SAGE PUBLICATIONS INC, 2018)
      Purpose: Bilinguals tend to experience “difficulties” with contrasts specific to their nondominant language. This study investigates the discrimination of the /ʎ/-/ʒ/ contrast of Majorcan Catalan by two groups of Catalan-Spanish bilinguals differing in their linguistic experience, Catalan- vs. Spanish-dominant. Methodology: Participants completed a categorical discrimination task to examine their perception of the following pairwise comparisons, relevant to assessing the perceptibility of the Majorcan Catalan /ʎ/-/ʒ/ contrast: [ʎ]-[ʒ], [ʎ]-[j], and [ʒ]-[j]. Data: Data consisted of arcsine-transformed proportion-correct responses obtained by means of a categorical discrimination task using the odd-item-out AXB paradigm. Findings: The results indicate that Spanish-dominant bilinguals are less accurate than Catalan-dominant ones in terms of their discrimination of the sounds involved in the /ʎ/-/ʒ/ contrast. Catalan-dominant participants discriminate any pairs involving [ʒ] very accurately. Interestingly, however, all participants find the [ʎ]-[j] pair difficult to discriminate. Originality: This study examines perception of a contrast not examined before, and its results suggest a surprising pattern of asymmetry in phonological representations of the target contrast. Significance: The results suggest that language dominance in the Catalan-Spanish contact community modulates discrimination of the /ʎ/-/ʒ/ contrast. The findings also suggest that Catalan-dominant listeners’ representation of /ʎ/ and /ʒ/ may be asymmetrical: The representation of /ʎ/ may be fuzzier than that of /ʒ/.
    • The language functions of tipo in Argentine vernacular

      Fernández, Julieta; University of Arizona, Department of Spanish and Portuguese (ELSEVIER SCIENCE BV, 2017-06)
      This article provides a case study account of the language functions of tipo, which is a pragmatic feature of Argentine Spanish vernacular, as used by 10 young adult native speakers of the language (ages 18-25), in the context of oral face-to-face and synchronous technology-mediated written interactions with young adult Spanish L2 learners. An examination of naturally occurring and self-reported language awareness data suggests that tipo has acquired a wide array of pragmatic functions it is a marker of hesitation, exemplification, reformulation, vagueness, and quoted speech. In its non-pragmatic marking uses, it can refer to an unspecified man, preface a hyponym, and be used to make a comparison. Participants' usage patterns, in conjunction with their understanding of sociopragmatic variability in the use of tipo, are discussed as a direction for research in colloquial features of youth vernacular.
    • Language in a global world: A case study of foreign languages in U.S. K-8 education

      Hellmich, Emily A.; Univ Arizona, French & Appl Linguist (WILEY, 2018)
      Over the past decade, there have been numerous calls to update U.S. education to reflect an increasingly global world (Hull & Hellmich, 2018). Foreign languages (FLs) are often perceived as central to these efforts (American Academy of Arts & Sciences, 2017). Despite this centrality, less is known about how FLs are understood in U.S. K-12 education today, particularly at the individual and school levels. Using an ecological theoretical frame and a case study research design, this article focused on one K-8 immersion school and examined (1) the discourses that teachers, administrators, parents, and students used to understand FLs in education; (2) how their understandings impacted the learning environment; and (3) how local beliefs and behaviors aligned with larger societal philosophies and practices. Findings revealed areas of both alignment and divergence from previous literature and highlight the complex understandings that are used to position and guide FL education.
    • The lapse function in Friedmann—Lemaître–Robertson–Walker cosmologies

      Melia, F.; Univ Arizona, Dept Phys, Program Appl Math; Univ Arizona, Dept Astron (ACADEMIC PRESS INC ELSEVIER SCIENCE, 2019-12)
      The Friedmann-LemaTtre-Robertson-Walker (FLRW) metric, the backbone of modem cosmology, is founded on the cosmological principle, which assumes homogeneity and isotropy throughout the cosmos. One of its simplifications is the choice of lapse function g(tt) = 1, regardless of which stress-energy tensor T-mu v is used in Einstein's field equations. It is sometimes argued that this selection is justified by gauge freedom, given that g(tt) in FLRW may be a function solely of t, not of the spatial coordinates, permitting a redefinition of the time. We show in this paper, however, that the comoving frame in the Hubble expansion is non inertial for all but a few special cases of the expansion factor a(t). Changing the gauge changes the frame of reference and cannot alter this property of the expansion profile, since it would of necessity reformat the metric using the coordinates of a noncomoving observer. We therefore suggest that the pre-selection of g(tt )= 1, independently of the equation of state in the cosmic fluid, incorrectly avoids the time dilation that ought to be present relative to the actual free-falling frame when (a) over dot not equal 0. (C) 2019 Elsevier Inc. All rights reserved.
    • Large 14C excursion in 5480 BC indicates an abnormal sun in the mid-Holocene

      Miyake, Fusa; Jull, A. J. Timothy; Panyushkina, Irina P.; Wacker, Lukas; Salzer, Matthew; Baisan, Christopher H.; Lange, Todd; Cruz, Richard; Masuda, Kimiaki; Nakamura, Toshio; et al. (NATL ACAD SCIENCES, 2017-01-31)
      Radiocarbon content in tree-rings can be an excellent proxy of the past incoming cosmic ray intensities to the Earth. Although such past cosmic ray variations have been studied by measurements of 14C contents in tree rings with ≧10 year time resolution for the Holocene (1), there are few annual 14C data. There is a little understanding about annual 14C variations in the past with the exception of a few periods including the AD774-775 annual 14C excursion (2). Here, we report the result of 14C measurements using the bristlecone pine tree rings for the period from 5490 BC to 5411 BC with 1-2 year resolution, and a finding of an extraordinarily large 14C increase (20‰) from 5481 BC to 5471 BC (the 5480 BC event). The 14C increase rate of this event is much larger than that of the normal Grand Solar Minima. We propose the possible causes of this event are a special phase of grand solar minimum, or a combination of successive solar proton events and a normal grand solar minimum.