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We report the first measurement of the elliptic anisotropy (v2) of the charm meson D0 at midrapidity (|y|<1) in Au+Au collisions at sNN=200 GeV. The measurement was conducted by the STAR experiment at RHIC utilizing a new high-resolution silicon tracker. The measured D0 v2 in 0%-80% centrality Au+Au collisions can be described by a viscous hydrodynamic calculation for a transverse momentum (pT) of less than 4 GeV/c. The D0 v2 as a function of transverse kinetic energy (mT-m0, where mT=pT2+m02) is consistent with that of light mesons in 10%-40% centrality Au+Au collisions. These results suggest that charm quarks have achieved local thermal equilibrium with the medium created in such collisions. Several theoretical models, with the temperature-dependent, dimensionless charm spatial diffusion coefficient (2πTDs) in the range of ∼2-12, are able to simultaneously reproduce our D0 v2 result and our previously published results for the D0 nuclear modification factor. © 2017 American Physical Society.

Background: Tetrazole derivatives such as 1-substituted dinitrobenzyl tetrazoles and their oxa and selanyl analogs have previously been studied against drug-susceptible and multidrugresistant mycobacteria. In addition, other tetrazole derivatives have been shown to inhibit CTX-M class A μ-lactamases. Objective: To study the antibacterial activity of 5-substituted aryl 1H-tetrazole derivatives. Methods: The antibacterial activity of several known 5-substituted aryl 1H-tetrazole derivatives was evaluated against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The activity was assessed by determining the minimum inhibitory concentration of these tetrazole derivatives and comparing them to the known antibiotics amoxicillin, trimethoprim and sulfamethoxazole. Results: Some derivatives showed significant antibacterial activity with the most active derivatives exhibiting a minimum inhibitory concentration (MIC) of 125-250 μg/mL against Staphylococcus aureus and Escherichia coli. Using some of these tetrazole compounds in combination with trimethoprim led to a synergistic effect that gave MIC values ranging from 0.24-1.95 μg/mL against Escherichia coli and 3.91-31.3 μg/mL against Staphylococcus aureus. The tetrazole derivatives were prepared in an isopropanol/water mixture using microwave heating at 160 °C for 1h. The cycloaddition between organonitriles and sodium azide was catalyzed by indium chloride. Conclusion: This study shows a significant synergistic effect between the tetrazole compounds tested and trimethoprim which could be used to potentially develop new antibacterial agents. © 2017 Bentham Science Publishers.

This article is one of the first to systematically assess the ability of state fragility measures to predict violent protests and adverse regime changes in countries. We focus on the Arab Spring as an example of a situation that such measures ought to predict. Through a variety of analyses, we find that none of the measures are predictive. We then create a simple model using the literature of protest and revolts to predict both the level of violence and the extent of regime change in the Arab Spring countries. This simpler model does a better job of predicting the level of involvement in the Arab Spring than any of the complex State Fragility Indexes. Thus, the goal of this article is not to explain the causes of the Arab Spring, but to add to the discussion of the predictive value of measures of instability.

Before 1944, countless Costa Rican travelers perished on the narrow rocky trail that traversed the 3,491 meter Cerro de la Muerte. Undaunted, between 1941 and 1944 U.S. engineers and Costa Rican workers built a 49-mile segment of the Inter-American Highway that conquered the Cerro. For many, both in the countryside and in the city, the roadway was a symbol of progress and modernization that inspired an image of the San José-centered state as a benevolent patriarch and the United States as a wealthy and generous Good Neighbor. The roadway, however, also had its detractors, namely communist labor organizers, who saw the project as a symbol of U.S. imperial exploitation that threatened Costa Rican sovereignty and harmed workers. The Communist press and labor organizers sought to mobilize highway workers and popular discontent against the roadway, but their efforts were largely ineffective. Indeed, ultimately, roadway workers, their families, and neighbors were grateful for the increased transportation and communication the roadway furnished their communities and the well-remunerated labor opportunities this transnational infrastructure provided. In sum, the roadway’s detractors failed to foster negative perceptions of the roadway as a symbol of the exploitative nature of the U.S. Empire on the ground.

Second language (L2) classroom research has sought to shed light on the processes and practices that develop L2 learners' abilities [Nunan, D. 2004. Task-based language teaching. London: Continuum; Verplaetse, L. 2014. Using big questions to apprentice students into language-rich classroom practices. TESOL Quarterly, 179, 632-641; Zeungler, J., & Mori, J. 2002. Microanalyses of classroom discourse: A critical consideration of method. Applied Linguistics, 23(3), 283-288]. Honing in on the micro-level of classroom tasks and even further into the language of the tasks can help to reveal the patterns in teacher- and student-talk that help scaffold students' academic literacy. Literacy, from a systemic functional view of language learning, entails having the tools to function in the social contexts that are valued in students' lives. This study illustrates how grounded ethnography was used in conjunction with functional discourse analysis to illuminate bi-literacy development in two third-year university Spanish writing classes. Findings uncovered unique patterns of tasks and oral interactions that helped build students' academic bi-literacy. While grammar tasks helped build students' knowledge of wording-meaning relationships, culture and writing tasks supported their evolving understanding of how language construes content. This study puts forth a systemic functional curricular model for literacy-based tasks that aims to bridge the previously observed language-content gap.

Background: Schools of nursing have moved to multiple choice test questions to help prepare students for licensure and practice. However, students can buy test banks to help them “get through” nursing school. Accurate assessment of nursing students' knowledge and judgment comprises access to test banks. Method: The purpose of this exploratory study was to gain an understanding about nursing faculty's knowledge concerning test bank security issues, to assess whether publishers were aware of this issue, and vendor's reasons for supplying test banks to students. Results: Overall, the results indicated that the majority of faculty were unaware of student access to test banks, and although most do not use test banks verbatim, general consensus existed that test bank security is a concern. Conclusion: Implications include increasing faculty awareness of test bank access by students, supporting educators to develop their own test bank items, and promoting security of all examinations.

Despite their close proximity, the complex interplay between the two Magellanic Clouds, the Milky Way and the resulting tidal features, is still poorly understood. Recent studies have shown that the Large Magellanic Cloud (LMC) has a very extended disc strikingly perturbed in its outskirts.We search for recent star formation in the far outskirts of the LMC, out to ~30° from its centre.We have collected intermediate-resolution spectra of 31 young star candidates in the periphery of the LMC and measured their radial velocity, stellar parameters, distance and age. Our measurements confirm membership to the LMC of six targets, for which the radial velocity and distance values match well with those of the Cloud. These objects are all young (10-50 Myr), main-sequence stars, projected between 7° and 13° from the centre of the parent galaxy. We compare the velocities of our stars with those of a disc model, and find that our stars have low to moderate velocity differences with the disc model predictions, indicating that they were formed in situ. Our study demonstrates that recent star formation occurred in the far periphery of the LMC, where thus far only old objects were known. The spatial configuration of these newly formed stars appears ring-like with a radius of 12 kpc and a displacement of 2.6 kpc from the LMC's centre. This structure, if real, would be suggestive of a star formation episode triggered by an off-centre collision between the Small Magellanic Cloud and the LMC's disc. © 2016 The Authors.

We report on speckle observations of binary stars carried out at the WIYN Telescope over the period from 2010 September through 2012 February, providing relative astrometry for 2521 observations of 883 objects, 856 of which are double stars and 27 of which are triples. The separations measured span a range of 0.01-1.75 arcsec. Wavelengths of 562, 692, and 880 nm were used, and differential photometry at one or more of these wavelengths is presented in most cases. 66 components were resolved for the first time. We also estimate detection limits at 0.2 and 1.0 arcsec for high-quality observations in cases where no companion was seen, a total of 176 additional objects. Detection limits vary based on observing conditions and signal-to-noise ratio, but are approximately 4 mag at 0.2 arcsec and 6 mag at 1.0 arcsec on average. Analyzing the measurement precision of the data set, we find that the individual separations obtained have linear measurement uncertainties of approximately 2 mas, and photometry is uncertain to approximately 0.1 mag in general. This work provides fundamental, well-calibrated data for future orbit and mass determinations, and we present three first orbits and total mass estimates of nearby K-dwarf systems as examples of this potential. © 2017. The American Astronomical Society. All rights reserved..

We report the discovery of HAT-P-67b, which is a hot-Saturn transiting a rapidly rotating F-subgiant. HAT-P-67b has a radius of Rp=2.085 -0.071 +0.096 RJ, and orbites a M∗ = 1.642-0.072 +0.155 M, R∗ = 2.546-0.099 +0.0084 R host star in a ∼4.81 day period orbit. We place an upper limit on the mass of the planet via radial velocity measurements to be Mp &lt; 0.59 MJ, and a lower limit of &gt;0.056 MJ by limitations on Roche lobe overflow. Despite being a subgiant, the host star still exhibits relatively rapid rotation, with a projected rotational velocity of v sin I∗ = 35.8 ±1.1 km s-1, which makes it difficult to precisely determine the mass of the planet using radial velocities. We validated HAT-P-67b via two Doppler tomographic detections of the planetary transit, which eliminate potential eclipsing binary blend scenarios. The Doppler tomographic observations also confirm that HAT-P-67b has an orbit that is aligned to within 12, in projection, with the spin of its host star. HAT-P-67b receives strong UV irradiation and is among one of the lowest density planets known, which makes it a good candidate for future UV transit observations in the search for an extended hydrogen exosphere. © 2017. The American Astronomical Society. All rights reserved.

In the era between the 1882 Chinese Exclusion Act and the Immigration Act of 1924, nativist advocates for immigration restriction commonly invoked metaphors of eating and digestion to support their cases. This essay draws on political, popular, and scientific discourses around immigration and digestion in order to analyze the affective power of the rhetorically constructed “body politic.” While numerous scholars have addressed the ways immigrants have been variously figured as threats to the nation—as pollutants, toxins, disease, floods, or invading armies—few have analyzed metaphors of eating and digestion. I argue that the national body became a metonym for the ideal (white) citizen body, which supported anti-immigrant rhetoric through metaphors of eating, digesting, and eliminating undesirable aliens—those who did not agree with the national stomach. The body politic came to represent the ideal US American body as individuals were invited to identify with the nation through the trope of the body politic; immigrants who did not share this ideal body were rendered undesirable through their association with indigestibility and disgust. This essay demonstrates the affective and thus political power that digestion metaphors provided, shedding light on an early instantiation of the disgust that pulses through twenty-first-century anti-immigrant discourse in the United States.

Many students with a history of speech or language impairment have an elevated risk of reading difficulty. Specific subgroups of these students remain at risk of reading problems even after clinical manifestations of a speech or language disorder have diminished. These students may require reading intervention within a general education system of supports and services. The first part of this article describes three speech-language disorders that place elementary students at risk of reading problems: functional speech disorders, childhood apraxia of speech, and specific language impairment. Emphasis is given to research findings on the reading outcomes of students with these disorders. The second part of the article provides recommendations within an RTI framework that will assist Student Support Teams in identifying, monitoring, and supporting these students. © 2017 Taylor & Francis Group, LLC.

Women’s perceptions of the prison experience and the punishing dimensions of their confinement are under-examined. To expand knowledge in this area, Sexton’s theory of penal consciousness is used to analyze formerly incarcerated women’s narratives about prison food. This analysis builds understanding about the lived experience of incarceration by explicating one dimension of prisoners’ understandings and perceptions of punishment. Women’s narratives describe both concrete and symbolic punishments associated with food. Participants spoke about poorly designed, sloppy food systems that left them feeling uncared for, ignored, frustrated, and humiliated. Women articulate experiences of hunger that reflect both a deprivation of adequate food and a rationing of humane attentions. These punishing perceptions may inhibit the efforts of social service and health providers to engage incarcerated and formerly incarcerated women in care. In contrast, exceptional participant narratives about positive, non-punishing food experiences suggest that ameliorated food systems could improve the lived experience of incarceration and promote the engagement in services that is needed to improve the outcomes of incarcerated and formerly incarcerated women.

Gaia DR1 positions are used to astrometrically calibrate three epochs’ worth of Subaru SuprimeCam images in the fields of globular cluster NGC 2419 and the Sextans dwarf spheroidal galaxy. Distortion-correction “maps” are constructed from a combination of offset dithers and reference to Gaia DR1. These are used to derive absolute proper motions in the field of NGC 2419. Notably, we identify the photometrically-detected Monoceros structure in the foreground of NGC 2419 as a kinematically-cold population of stars, distinct from Galactic-field stars. This project demonstrates the feasibility of combining Gaia with deep, ground-based surveys, thus extending high-quality astrometry to magnitudes beyond the limits of Gaia.

Purpose: The toddler years are a critical period for language development and growth. We investigated how event-related potentials (ERPs) to repeated and novel nonwords are associated with clinical assessments of language in young children. In addition, nonword repetition (NWR) was used to measure phonological working memory to determine the unique and collective contribution of ERP measures of phonemic discrimination and NWR as predictors of language ability. Method: Forty children between the ages of 24-48 months participated in an ERP experiment to determine phonemic discrimination to repeated and novel nonwords in an old/new design. Participants also completed a NWR task to explore the contribution of phonological working memory in predicting language. Results: ERP analyses revealed that faster responses to novel stimuli correlated with higher language performance on clinical assessments of language. Regression analyses revealed that an earlier component was associated with lower level phonemic sensitivity, and a later component was indexing phonological working memory skills similar to NWR. Conclusion: Our findings suggest that passive ERP responses indexing phonological discrimination and phonological working memory are strongly related to behavioral measures of language.

This article explores trust relationships in schools that involve disparities in power. Trust is a key factor in developing a positive school culture and strong leadership in schools. Even with the flattening of hierarchies through more distributive models of leadership, disparities in power exist and they influence the trust relationships in schools. Through both French and Raven’s and Follett’s conceptualisations of power, five brief autobiographical stories about trust in schools are deconstructed. Lessons for leadership are gleaned from the power relationships in the autobiographical stories of trust shared by public school educators. In addition, general recommendations are offered that are relevant for all levels of school leadership including but not limited to the instructional coach, the curriculum supervisor, the building principal, and the classroom teacher.

We present results from a Keck/HIRES radial velocity campaign to study four sub-Saturn-sized planets, K2-27b, K2-32b, K2-39b, and K2-108b, with the goal of understanding their masses, orbits, and heavy-element enrichment. The planets have similar sizes (RP=4.5-5.5 ), but have dissimilar masses (MP=16-60 ), implying a diversity in their core and envelope masses. K2-32b is the least massive (MP = 16.5 ± 2.7 M) and orbits in close proximity to two sub-Neptunes near a 3:2:1 period commensurability. K2-27b and K2-39b are significantly more massive at MP = 30.9 ± 4.6 M and MP = 39.8 ± 4.4 M, respectively, and show no signs of additional planets. K2-108b is the most massive at MP = 59.4 ± 4.4 M, implying a large reservoir of heavy elements of about ≈50 . Sub-Saturns as a population have a large diversity in planet mass at a given size. They exhibit remarkably little correlation between mass and size; sub-Saturns range from ≈6-60 M, regardless of size. We find a strong correlation between planet mass and host star metallicity, suggesting that metal-rich disks form more massive planet cores. The most massive sub-Saturns tend to lack detected companions and have moderately eccentric orbits, perhaps as a result of a previous epoch of dynamical instability. Finally, we observe only a weak correlation between the planet envelope fraction and present-day equilibrium temperature, suggesting that photo-evaporation does not play a dominant role in determining the amount of gas sub-Saturns accrete from their protoplanetary disks. © 2017. The American Astronomical Society. All rights reserved..

A scholarly article by author Jason C. Patalinghug, published in the Journal of Applied Business and Economics