886 research outputs found

    Construction and Calibration of a Streaked Optical Spectrometer for Shock Temperature

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    Here we describe the implementation and calibration of a streaked visible spectrometer (SVS) for optical pyrometry and emission/absorption spectroscopy on light gas gun platforms in the UC Davis Shock Compression Laboratory. The diagnostic consists of an optical streak camera coupled to a spectrometer to provide temporally and spectrally-resolved records of visible emission from dynamically-compressed materials. Fiber optic coupling to the sample enables a small diagnostic footprint on the target face and flexibility of operation on multiple launch systems without the need for open optics. We present the details of calibration (time, wavelength and spectral radiance) for absolute temperature determination and present benchmark measurements of system performance.Comment: 6 pages, 3 figures Davies, E., et al. (accepted). In J. Lane, T. Germann, and M. Armstrong (Eds.), 21st Biennial APS Conference on Shock Compression of Condensed Matter (SCCM19). AIP Publishin

    Factors that Influence Teachers’ Views on Standardized Tests

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    The central aim of this study was to explore K-12 teachers’ (N = 183) attitudes about standardized tests as a function of experience, instructional level, student population, and type of school. The Teachers’ Views on Standardized Tests Questionnaire was developed to assess teachers’ perceptions of the impact of standardized tests on practice. All survey items were intended to measure a facet of teachers’ attitudes regarding the necessity of standardized tests and their influence on best practices. Findings from this study indicated that special education and inclusion teachers viewed standardized tests as more negatively influencing instruction than general education teachers. There were also significant differences by instructional level and type of school (i.e., public vs. independent). Compared to elementary teachers, middle and high school teachers’ views were more negative, and public school educators perceived standardized assessments as having a more negative influence on instruction than teachers in independent schools. Finally, elementary school teachers reported that the standards of learning were more appropriate in contrast to middle and high school teachers

    Induction of carcinoembryonic antigen expression in a three-dimensional culture system

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    MIP-101 is a poorly differentiated human colon carcinoma cell line established from ascites that produces minimal amounts of carcinoembryonic antigen (CEA), a 180 kDa glycoprotein tumor marker, and nonspecific cross-reacting antigen (NCA), a related protein that has 50 and 90 kDa isoforms, in vitro in monolayer culture. MIP-101 produces CEA when implanted into the peritoneum of nude mice but not when implanted into subcutaneous tissue. We tested whether MIP-101 cells may be induced to express CEA when cultured on microcarrier beads in three-dimensional cultures, either in static cultures as non-adherent aggregates or under dynamic conditions in a NASA-designed low shear stress bioreactor. MIP- 101 cells proliferated well under all three conditions and increased CEA and NCA production 3 - 4 fold when grown in three-dimensional cultures compared to MIP-101 cells growing logarithmically in monolayers. These results suggest that three-dimensional growth in vitro simulates tumor function in vivo and that three-dimensional growth by itself may enhance production of molecules that are associated with the metastatic process

    Deconstructing Stereotypes: Stature, Match-playing Time, and Performance in Elite Women\u27s World Cup Soccer

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    Recruiting companies recommend elite female soccer players be ≥165 cm (5\u275″) in stature. This study investigated if stature limits match-playing time and performance in elite World Cup soccer among players, positions, and countries. We hypothesized stature would not affect match-playing time or performance. Descriptive data were collected on 552 players from 2019 FIFA Women\u27s World Cup. Odds ratios determined likelihood of starting for players ≥165 cm. ANOVAs compared playing time between stature groups, among positions, and between countries. Performance factors including assists, goals, attempts, corners, shots blocked, and defending blocks were reported. Independent t-tests compared differences between players (≥165 cm, \u3c 165 cm). Data are reported, mean difference [95% confidence interval] [MD (95%CI)] and effect sizes (ES). On average, 32.3% of players were F = 0.98, p = 0.32), matches (F = 0.27 p = 0.59), or average minutes per match (F = 0.48, p = 0.49) between stature groups, regardless of position. No differences existed in playing time between players ≥165 cm among any positions (p \u3e 0.05), or between countries (p \u3e 0.05). Taller mid-fielders exhibited greater performance in goals, assists, attempts, shots blocked, and defending blocks (MD [95%CI] ES; assists, -0.44[-0.76,-0.11]0.59, p = 0.009; goals, -0.35[-0.69,-0.01]0.44, p = 0.047); attempts, 3.14[1.38, 4.90]0.80, p = 0.001; corners, 2.04[0.12, 3.95]0.48, p = 0.037; shots blocked, 0.96[0.40, 1.51]0.75, p = 0.001; defending blocks, 0.43[0.32,0.82]0.48, p = 0.035), however, actual differences were minimal. Our findings indicate stature does not inhibit playing and performing elite women\u27s soccer, as nearly one-third of players were \u3c165 \u3ecm

    ProSight PTM 2.0: improved protein identification and characterization for top down mass spectrometry

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    ProSight PTM 2.0 (http://prosightptm2.scs.uiuc.edu) is the next generation of the ProSight PTM web-based system for the identification and characterization of proteins using top down tandem mass spectrometry. It introduces an entirely new data-driven interface, integrated Sequence Gazer for protein characterization, support for fixed modifications, terminal modifications and improved support for multiple precursor ions (multiplexing). Furthermore, it supports data import and export for local analysis and collaboration

    AhrC and Eep are biofilm infection-associated virulence factors in enterococcus faecalis

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    Enterococcus faecalis is part of the human intestinal microbiome and is a prominent cause of health care-associated infections. The pathogenesis of many E. faecalis infections, including endocarditis and catheter-associated urinary tract infection (CAUTI), is related to the ability of clinical isolates to form biofilms. To identify chromosomal genetic determinants responsible for E. faecalis biofilm-mediated infection, we used a rabbit model of endocarditis to test strains with transposon insertions or in-frame deletions in biofilm-associated loci: ahrC, argR, atlA, opuBC, pyrC, recN, and sepF. Only the ahrC mutant was significantly attenuated in endocarditis. We demonstrate that the transcriptional regulator AhrC and the protease Eep, which we showed previously to be an endocarditis virulence factor, are also required for full virulence in murine CAUTI. Therefore, AhrC and Eep can be classified as enterococcal biofilm-associated virulence factors. Loss of ahrC caused defects in early attachment and accumulation of biofilm biomass. Characterization of ahrC transcription revealed that the temporal expression of this locus observed in wild-type cells promotes initiation of early biofilm formation and the establishment of endocarditis. This is the first report of AhrC serving as a virulence factor in any bacterial species

    Rethinking Sudan Studies: A Post-2011 Manifesto

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    Abstract This essay appraises “Sudan Studies” following the 2011 secession of South Sudan. It asks two questions. First, what has Sudan Studies been as a colonial and postcolonial field of academic inquiry and how should or must it change? Second, should we continue to write about a single arena of Sudan Studies now that Sudan has split apart? The authors advance a “manifesto” for Sudan Studies by urging scholars to map out more intellectual terrain by attending to non-elite actors and women; grass-roots and local history; the environment and the arts; oral sources; and interdisciplinary studies of culture, politics, and society. They propose that scholars can transcend the changing boundaries of the nation-state, and recognize connections forged through past and present migrations and contacts, by studying the Sudan as a zone rather than a fixed country. Finally, in their introduction to this bilingual special issue, they highlight the increasing relevance of French scholarship to the endeavor of rethinking Sudan Studies. Résumé Cet essai évalue la situation des « études soudanaises » après la sécession du Soudan du Sud. Il pose deux questions. La première : En quoi ont consisté les études soudanaises en tant que domaine colonial et postcolonial de recherche universitaire et dans quelle mesure doivent-elles changer, si tant est qu\u27elles doivent changer ? La seconde : Devrions-nous continuer à baser nos écrits sur un domaine unique d\u27études soudanaises maintenant que le Soudan est divisé ? Les auteurs proposent un « manifeste » pour les études soudanaises en exhortant les experts à cartographier un terrain intellectuel élargi en s\u27intéressant aux acteurs ne faisant pas partie des élites et des femmes ; à l\u27histoire de la base populaire et locale ; à l\u27environnement et à l\u27art ; aux sources orales ; et aux études interdisciplinaires portant sur la culture, la politique et la société. Ils avancent que les chercheurs peuvent aller au-delà des frontières en mutation de l\u27État-nation et reconnaitre les connexions établies grâce aux migrations et aux contacts passés et présents en étudiant le Soudan comme zone plutôt que comme un pays fixe. Enfin, dans leur introduction à ce numéro bilingue spécial, ils mettent en relief la pertinence croissance des travaux universitaires français dans le cadre de l\u27initiative visant à repenser les études soudanaises

    Meta-analysis of randomized trials on drug-eluting stents vs. bare-metal stents in patients with acute myocardial infarction

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    Aims To compare the efficacy and safety of drug-eluting stents vs. bare-metal stents in patients with acute ST-segment elevation myocardial infarction. Methods and results We performed a meta-analysis of eight randomized trials comparing drug-eluting stents (sirolimus-eluting or paclitaxel-eluting stents) with bare-metal stents in 2786 patients with acute ST-segment elevation myocardial infarction. All patients were followed up for a mean of 12.0-24.2 months. Individual data were available for seven trials with 2476 patients. The primary efficacy endpoint was the need for reintervention (target lesion revascularization). The primary safety endpoint was stent thrombosis. Other outcomes of interest were death and recurrent myocardial infarction. Drug-eluting stents significantly reduced the risk of reintervention, hazard ratio of 0.38 (95% CI, 0.29-0.50), P < 0.001. The overall risk of stent thrombosis: hazard ratio of 0.80 (95% CI, 0.46-1.39), P = 0.43; death: hazard ratio of 0.76 (95% CI, 0.53-1.10), P = 0.14; and recurrent myocardial infarction: hazard ratio of 0.72 (95% CI, 0.48-1.08, P = 0.11) was not significantly different for patients receiving drug-eluting stents vs. bare-metal stents. Conclusion The use of drug-eluting stents in patients with acute ST-segment elevation myocardial infarction is safe and improves clinical outcomes by reducing the risk of reintervention compared with bare-metal stent
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