238 research outputs found

    Running head: IMPROVING STUDENT ACHIEVEMENT 1 A Systems-based Synthesis of Research Related to Improving Students ’ Academic Performance

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    This paper addresses the issue of school improvement by looking to research on both the variables that should be the focus of school improvement efforts as well as factors that make it more likely that the organization will actually implement research findings. Issues of transformational leadership, instructional leadership, and high functioning teams are addressed; Hattie’s (2009) review of over 800 meta-analyses of variables related to school achievement is the primary source of identifying classroom and school variables that can be addressed by educators. As developed nations move out of the industrial age into the information/conceptual age, there is an ongoing debate about how to best prepare children and youth for adult success in the twenty-first century (Huitt, 1999b, 2007). While there is a consensus that schools should play a major role in this process, there is less agreement about exactly what that role should be. Some believe that the primary focus of schools should be academic preparation of students (Hirsch, 1987, 1996; Tienken, & Wilson, 2001), that classroom teachers are primarily responsible for student academic achievement (Darling-Hammond, 2000), and schools should efficiently and effectively organize themselves towards that task (Engelmann & Carnine, 1991). These effort

    A Spectacular Hα\alpha Complex in Virgo: Evidence for a Collision Between M86 and NGC 4438 and Implications for Collisional ISM Heating of Ellipticals

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    Deep wide-field Hα\alpha+[NII] imaging around the Virgo cluster giant elliptical galaxy M86 reveals a highly complex and disturbed ISM/ICM. The most striking feature is a set of Hα\alpha filaments which clearly connect M86 with the nearby disturbed spiral NGC 4438 (23′'=120 kpc projected away), providing strong evidence for a previously unrecognized collision between them. Spectroscopy of selected regions show a fairly smooth velocity gradient between M86 and NGC 4438, consistent with the collision scenario. Such a collision would impart significant energy into the ISM of M86, probably heating the gas and acting to prevent the gas from cooling to form stars. We propose that cool gas stripped from NGC 4438 during the collision and deposited in its wake is heated by shocks, ram pressure drag, or thermal conduction, producing most of the Hα\alpha filaments. Some Hα\alpha filaments are associated with the well-known ridge of bright X-ray emission to the NW of the nucleus, suggesting that the collision is responsible for peculiarities of M86 previously ascribed to other effects. M86 is radio-quiet, thus AGN heating is unlikely to play a significant role. The M86 system has implications for understanding the role of gravitational interactions in the heating of the ISM in ellipticals, and how collisions in clusters transform galaxies.Comment: 6 pages, 2 figures. For high-resolution images, see http://www.astro.yale.edu/tal/research/index.htm

    Chandra Observations of the Interacting NGC 4410 Galaxy Group

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    We present high resolution X-ray imaging data from the ACIS-S instrument on the Chandra telescope of the nearby interacting galaxy group NGC 4410. Four galaxies in the inner portion of this group are clearly detected by Chandra, including the peculiar low luminosity radio galaxy NGC 4410A. In addition to a nuclear point source, NGC 4410A contains diffuse X-ray emission, including an X-ray ridge extending out to about 12" (6 kpc) to the northwest of the nucleus. This ridge is coincident with an arc of optical emission-line gas, which has previously been shown to have optical line ratios consistent with shock ionization. This structure may be due to an expanding superbubble of hot gas caused by supernovae and stellar winds or by the active nucleus. The Chandra observations also show four or five possible compact ultra-luminous X-ray (ULX) sources (L(x) >= 10^39 erg/s) associated with NGC 4410A. At least one of these candidate ULXs appears to have a radio counterpart, suggesting that it may be due to an X-ray binary with a stellar-mass black hole, rather than an intermediate mass black hole. In addition, a faint diffuse intragroup X-ray component has been detected between the galaxies (L(x) ~ 10^41 erg/s). This supports the hypothesis that the NGC 4410 group is in the process of evolving via mergers from a spiral-dominated group (which typically have no X-ray-emitting intragroup gas) to an elliptical-dominated group (which often have a substantial intragroup medium).Comment: 27 pages, 14 figures; Accepted by Astronomical Journal; color images at http://www.etsu.edu/physics/bsmith/research/n4410.htm

    The Two-dimensional XMM-Newton Group Survey: z<0.012 groups

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    We present the results of the 2-dimensional XMM-Newton Group Survey (2dXGS), an archival study of nearby galaxy groups. In this paper we consider eleven nearby systems (z<0.012) in Mulchaey et al. (2003), which span a broad range in X-ray luminosity from 10^40 to 10^43 ergs/s. We measure the iron abundance and temperature distribution in these systems and derive pressure and entropy maps. We find statistically significant evidence for structure in the entropy and pressure of the gas component of seven groups on the 10-20% level. The XMM-Newton data for the three groups with best statistics also suggest patchy metalicity distributions within the central 20--50 kpc of the brightest group galaxy, probed with 2-10 kpc resolution. This provides insights into the processes associated with thermalization of the stellar mass loss. Analysis of the global properties of the groups reveals a subclass of X-ray faint groups, which are characterized by both higher entropy and lower pressure. We suggest that the merger history of the central elliptical is responsible for both the source and the observed thermodynamical properties of the hot gas of the X-ray faint groups.Comment: 18 pages, ApJ, 646, 143, 200

    Properties of the H-alpha-emitting Circumstellar Regions of Be Stars

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    Long-baseline interferometric observations obtained with the Navy Prototype Optical Interferometer of the H-alpha-emitting envelopes of the Be stars eta Tauri and beta Canis Minoris are presented. For compatibility with the previously published interferometric results in the literature of other Be stars, circularly symmetric and elliptical Gaussian models were fitted to the calibrated H-alpha observations. The models are sufficient in characterizing the angular distribution of the H-alpha-emitting circumstellar material associated with these Be stars. To study the correlations between the various model parameters and the stellar properties, the model parameters for eta Tau and beta CMi were combined with data for other Be stars from the literature. After accounting for the different distances to the sources and stellar continuum flux levels, it was possible to study the relationship between the net H-alpha emission and the physical extent of the H-alpha-emitting circumstellar region. A clear dependence of the net H-alpha emission on the linear size of the emitting region is demonstrated and these results are consistent with an optically thick line emission that is directly proportional to the effective area of the emitting disk. Within the small sample of stars considered in this analysis, no clear dependence on the spectral type or stellar rotation is found, although the results do suggest that hotter stars might have more extended H-alpha-emitting regions.Comment: 24 pages, 16 figures, accepted for publication in Ap

    Minimally Invasive Mitral Valve Surgery III: Training and Robotic-Assisted Approaches.

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    Minimally invasive mitral valve operations are increasingly common in the United States, but robotic-assisted approaches have not been widely adopted for a variety of reasons. This expert opinion reviews the state of the art and defines best practices, training, and techniques for developing a successful robotics program

    Minimally Invasive Mitral Valve Surgery I: Patient Selection, Evaluation, and Planning.

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    Widespread adoption of minimally invasive mitral valve repair and replacement may be fostered by practice consensus and standardization. This expert opinion, first of a 3-part series, outlines current best practices in patient evaluation and selection for minimally invasive mitral valve procedures, and discusses preoperative planning for cannulation and myocardial protection

    Minimally Invasive Mitral Valve Surgery II: Surgical Technique and Postoperative Management.

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    Techniques for minimally invasive mitral valve repair and replacement continue to evolve. This expert opinion, the second of a 3-part series, outlines current best practices for nonrobotic, minimally invasive mitral valve procedures, and for postoperative care after minimally invasive mitral valve surgery

    1957 Ruby Yearbook

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    A digitized copy of the 1957 Ruby, the Ursinus College yearbook.https://digitalcommons.ursinus.edu/ruby/1060/thumbnail.jp

    Long-term survivors of early breast cancer treated with chemotherapy are characterized by a pro-inflammatory biomarker profile compared to matched controls

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    Background: Chemo- and radiotherapy for breast cancer (BC) can lead to cardiotoxicity even years after the initial treatment. The pathophysiology behind these late cardiac effects is poorly understood. Therefore, we studied a large panel of biomarkers from different pathophysiological domains in long-term BC survivors, and compared these to matched controls. Methods and results: In total 91 biomarkers were measured in 688 subjects: 342 BC survivors stratified either to treatment with chemotherapy ± radiotherapy (n = 170) or radiotherapy alone (n = 172) and matched controls. Mean age was 59 ± 9 years and 65 ± 8 years for women treated with chemotherapy ± radiotherapy and radiotherapy alone, respectively, with a mean time since treatment of 11 ± 5.5 years. No biomarkers were differentially expressed in survivors treated with radiotherapy alone vs. controls (P for all >0.1). In sharp contrast, a total of 19 biomarkers were elevated, relative to controls, in BC survivors treated with chemotherapy ± radiotherapy after correction for multiple comparisons (P <0.05 for all). Network analysis revealed upregulation of pathways relating to collagen degradation and activation of matrix metalloproteinases. Furthermore, several inflammatory biomarkers including growth differentiation factor 15, monocyte chemoattractant protein 1, chemokine (C-X-C motif) ligand 16, tumour necrosis factor super family member 13b and proprotein convertase subtilisin/kexin type 9, elevated in survivors treated with chemotherapy, showed an independent association with lower left ventricular ejection fraction. Conclusion: Breast cancer survivors treated with chemotherapy ± radiotherapy show a distinct biomarker profile associated with mild cardiac dysfunction even 10 years after treatment. These results suggest that an ongoing pro-inflammatory state and activation of matrix metalloproteinases following initial treatment with chemotherapy might play a role in the observed cardiac dysfunction in late BC survivors
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