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Slavic Studies and Slavic Librarianship in the United States: A Post-Cold War Perspective (Excerpts)
Get PDFThis article reprints excerpts from Aaron Trehub’s piece about the relationship between Slavic studies and Slavic librarianship in the United States in the immediate aftermath of the end of the Cold War. The author, who at the time was Slavic librarian and bibliographer (and former Soviet affairs analyst), notes that through a curious quirk of history, the collapse of communism coincided with the birth of a powerful new communications medium (the World Wide Web). Together, these geopolitical and technological developments have fundamentally changed librarianship in general and Slavic librarianship in particular. Trehub’s discussion of the various day-to-day difficulties experienced by Slavic librarians in the post-Cold War period pays special attention to the challenges that new information technologies create for patrons, as well as the instructional burden that this places on librarians. He suggests that excessive reliance on the Web may erode the capacity to reason critically, but admits that the longterm effects of digitization on education and research are unclear. In effect, Trehub’s essay provides the historical background for reevaluating what competencies constitute Slavic information literacy in the twenty-first century.PublishedYe
Statistical correlation of low-altitude ENA emissions with geomagnetic activity from IMAGE/MENA observations
Get PDFPlasma sheet particles transported Earthward during times of active magnetospheric convection can interact with exospheric/thermospheric neutrals through charge exchange. The resulting Energetic Neutral Atoms (ENAs) are free to leave the influence of the magnetosphere and can be remotely detected. ENAs associated with low-altitude (300-800km) ion precipitation in the high-latitude atmosphere/ionosphere are termed low-altitude emissions (LAEs). Remotely observed LAEs are highly nonisotropic in velocity space such that the pitch angle distribution at the time of charge exchange is near 90 degrees. The Geomagnetic Emission Cone of LAEs can be mapped spatially, showing where proton energy is deposited during times of varying geomagnetic activity. In this study we present a statistical look at the correlation between LAE flux (intensity and location) and geomagnetic activity. The LAE data are from the MENA imager on the IMAGE satellite over the declining phase of solar cycle 23 (2000-2005). The SYM-H, AE, and Kp indices are used to describe geomagnetic activity. The goal of the study is to evaluate properties of LAEs in ENA images and determine if those images can be used to infer properties of ion precipitation. Results indicate a general positive correlation to LAE flux for all three indices, with the SYM-H showing the greatest sensitivity. The magnetic local time distribution of LAEs is centered about midnight and spreads with increasing activity. The invariant latitude for all indices has a slightly negative correlation. The combined results indicate LAE behavior similar to that of ion precipitation.PublishedYe
Racial Microaggressions in Academic Libraries: Results of a Survey of Minority and Non-Minority Librarians
Get PDFThere is relatively little literature on racism within the profession of academic librarianship. To investigate academic librarians’ experiences of racism, this research project uses the framework of racial microaggressions, which are subtle, denigrating messages directed toward people of color. According to the results of an online survey, some librarians of color have had racial microaggressions directed at them by their colleagues. Non-minority librarians, however, are unlikely to recognize these disparaging exchanges.PublishedYe
Implementing ePortfolios in English Education: Delights, Dilemmas, and Recommendations
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Global images of trapped ring current ions during main phase of 17 March 2015 geomagnetic storm as observed by TWINS
Get PDFA unique view of the trapped particles in the inner magnetosphere provided by energetic neutral atom (ENA) imaging is used to observe the dynamics of the spatial structure and the pitch angle anisotropy on a global scale during the last 6h of the main phase of a large geomagnetic storm (minimum SYM-H=-230nT) that began on 17 March 2015. Ion flux and pressure anisotropy obtained from Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS) ENA images are shown. The ion flux shows two peaks, an inner one at approximately radii=3-4 R-E in the dusk-to-midnight sector and an outer peak at radii=8-9 R-E prior to midnight. The inner peak is relatively stationary during the entire period with some intensification during the final steep decline in SYM-H to its minimum. The outer peak shows the significant temporal variation brightening and dimming and finally disappearing at the end of the main phase. The pressure anisotropy shows the expected perpendicular pitch angles inside of L=6 but shows parallel pitch angles at greater L values. This is interpreted as consistent with pitch angle-dependent drift as modeled in the Tsy05 magnetic field and Comprehensive Inner Magnetosphere-Ionosphere simulations. The TWINS results are compared directly with Radiation Belt Storm Probes Ion Composition Experiment (RBSPICE)-A measurements. Using 15min snapshots of flux and pressure anisotropy from TWINS along the path of RBSPICE-A during the 6h focused upon in this study, the essential features displayed in the TWINS global images are supported.PublishedYe
Statistical correlation of low-altitude ENA emissions with geomagnetic activity from IMAGE/MENA observations
Get PDFPlasma sheet particles transported Earthward during times of active magnetospheric convection can interact with exospheric/thermospheric neutrals through charge exchange. The resulting Energetic Neutral Atoms (ENAs) are free to leave the influence of the magnetosphere and can be remotely detected. ENAs associated with low-altitude (300-800km) ion precipitation in the high-latitude atmosphere/ionosphere are termed low-altitude emissions (LAEs). Remotely observed LAEs are highly nonisotropic in velocity space such that the pitch angle distribution at the time of charge exchange is near 90 degrees. The Geomagnetic Emission Cone of LAEs can be mapped spatially, showing where proton energy is deposited during times of varying geomagnetic activity. In this study we present a statistical look at the correlation between LAE flux (intensity and location) and geomagnetic activity. The LAE data are from the MENA imager on the IMAGE satellite over the declining phase of solar cycle 23 (2000-2005). The SYM-H, AE, and Kp indices are used to describe geomagnetic activity. The goal of the study is to evaluate properties of LAEs in ENA images and determine if those images can be used to infer properties of ion precipitation. Results indicate a general positive correlation to LAE flux for all three indices, with the SYM-H showing the greatest sensitivity. The magnetic local time distribution of LAEs is centered about midnight and spreads with increasing activity. The invariant latitude for all indices has a slightly negative correlation. The combined results indicate LAE behavior similar to that of ion precipitation.Publishe
George Henry Lewes, the Real Man of Science Behind George Eliot's Fictional Pedants
Get PDFThis paper demonstrates that George Eliot drew on George Henry Lewes’s actual experience as an emerging scientist in her depiction of two fictional scholars, Edward Casaubon of Middlemarch and Proteus Merman, a lesser-known character from the chapter entitled “How We Encourage Research” in her final work, Impressions of Theophrastus Such. After Thomas Huxley published a devastating review of Lewes’s first book of science, Comte’s Philosophy of the Sciences, the evidence suggests that Lewes became highly focused on disproving his critics and earning lasting recognition as a scientist, a feat he expected to achieve with his five-volume series, Problems of Life and Mind. The paper concludes with a discussion of what purpose Eliot may have intended when she modeled these characters after George Henry Lewes, her consistently defended partner.PublishedYe
Hall effect control of magnetotail dawn-dusk asymmetry: A three-dimensional global hybrid simulation
Get PDFMagnetotail reconnection and related phenomena (e.g., flux ropes, dipolarizing flux bundles, flow bursts, and particle injections) occur more frequently on the duskside than on the dawnside. Because this asymmetry can directly result in dawn-dusk asymmetric space weather effects, uncovering its physical origin is important for better understanding, modeling, and prediction of the space weather phenomena. However, the cause of this pervasive asymmetry is unclear. Using three-dimensional global hybrid simulations, we demonstrate that the Hall physics in the magnetotail current sheet is responsible for the asymmetry. The current sheet thins progressively under enhanced global convection; when its thickness reaches ion kinetic scales, some ions are decoupled from the magnetized electrons (the Hall effect). The resultant Hall electric field E-z is directed toward the neutral plane. The Hall effect is stronger (grows faster) on the duskside; i.e., more ions become unmagnetized there and do not comove with the magnetized dawnward E-z x B-x drifting electrons, thus creating a larger additional cross-tail current intensity j(y) (in addition to the diamagnetic current) on the duskside, compared to the dawnside. The stronger Hall effect strength on the duskside is controlled by the higher ion temperature, thinner current sheet, and smaller normal magnetic field B-z there. These asymmetric current sheet properties are in turn controlled by two competing processes that correspond to the Hall effect: (1) the dawnward E x B drift of the magnetic flux and magnetized ions and electrons and (2) the transient motion of the unmagnetized ions which do not execute E x B drift.Publishe
Purinergic P2Y2 Receptor Control of Tissue Factor Transcription in Human Coronary Artery Endothelial Cells NEW AP-1 TRANSCRIPTION FACTOR SITE AND NEGATIVE REGULATOR
Get PDFWe recently reported that the P2Y2 receptor (P2Y2R) is the predominant nucleotide receptor expressed in human coronary artery endothelial cells (HCAEC) and that P2Y2R activation by ATP or UTP induces dramatic up-regulation of tissue factor (TF), a key initiator of the coagulation cascade. However, the molecular mechanism of this P2Y2R-TF axis remains unclear. Here, we report the role of a newly identified AP-1 consensus sequence in the TF gene promoter and its original binding components in P2Y2R regulation of TF transcription. Using bioinformatics tools, we found that a novel AP-1 site at -1363 bp of the human TF promoter region is highly conserved across multiple species. Activation of P2Y2R increased TF promoter activity and mRNA expression in HCAEC. Truncation, deletion, and mutation of this distal AP-1 site all significantly suppressed TF promoter activity in response to P2Y2R activation. EMSA and ChIP assays further confirmed that upon P2Y2R activation, c-Jun, ATF-2, and Fra-1, but not the typical c-Fos, bound to the new AP-1 site. In addition, loss-of-function studies using siRNAs confirmed a positive transactivation role of c-Jun and ATF-2 but unexpectedly revealed a strong negative role of Fra-1 in P2Y2R-induced TF up-regulation. Furthermore, we found that P2Y2R activation promoted ERK1/2 phosphorylation through Src, leading to Fra-1 activation, whereas Rho/JNK mediated P2Y2R-induced activation of c-Jun and ATF-2. These findings reveal the molecular basis for P2Y G protein-coupled receptor control of endothelial TF expression and indicate that targeting the P2Y2R-Fra-1-TF pathway may be an attractive new strategy for controlling vascular inflammation and thrombogenicity associated with endothelial dysfunction.PublishedYe