5,353 research outputs found

    Historical Representation of Immigration in Intermediate Elementary and Middle Grade Trade Books

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    Education initiatives require social studies, history, and civics teachers integrate multiple texts from diverse perspectives and English, reading, and language arts educators spend half their allotted time on non-fiction. The changes are not accompanied with ready-made curricula, which will likely increase the place of non-fiction trade books in various curricula. Historical misrepresentations appear in trade books, yet most topics have not been empirically examined. This inquiry explores trade books’ historical representation of immigration and immigrants’ experiences. The data pool was organized by books intended for students in Intermediate Elementary (3-5) and Middle Grades (6-8), which enabled consideration of spiraling and patterns of representation between grade ranges. Findings included patterns based on grade ranges (genre, integration of primary sources, and representation of immigrants’ motivation), historical misrepresentation (acclimation, Eurocentrism, and xenophobia), and blatant omission (business influence and historical connections to contemporary events). Findings have implications for classroom use, which include literacy circles and suggestions for specific books with topics of intrigue

    Historical Representation of Immigration in Intermediate Elementary and Middle Grade Trade Books

    Get PDF
    Education initiatives require social studies, history, and civics teachers integrate multiple texts from diverse perspectives and English, reading, and language arts educators spend half their allotted time on non-fiction. The changes are not accompanied with ready-made curricula, which will likely increase the place of non-fiction trade books in various curricula. Historical misrepresentations appear in trade books, yet most topics have not been empirically examined. This inquiry explores trade books’ historical representation of immigration and immigrants’ experiences. The data pool was organized by books intended for students in Intermediate Elementary (3-5) and Middle Grades (6-8), which enabled consideration of spiraling and patterns of representation between grade ranges. Findings included patterns based on grade ranges (genre, integration of primary sources, and representation of immigrants’ motivation), historical misrepresentation (acclimation, Eurocentrism, and xenophobia), and blatant omission (business influence and historical connections to contemporary events). Findings have implications for classroom use, which include literacy circles and suggestions for specific books with topics of intrigue

    Managing in the regulatory thicket: regulation legitimacy and expertise

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    While the influence of government regulation on organizations is undeniable, empirical research in this field is scarce. This study investigates how the understanding of and attitudes towards government regulation among public, nonprofit, and for-profit managers affect organizational performance, using U.S. nursing homes as the empirical setting. Our findings suggest that managers’ perceptions of regulation legitimacy – views of regulation fairness, inspectors’ effectiveness, and internal utility of the mandates – positively affect service quality. Sub-group analysis suggests that the managers’ views of regulation matter in nonprofit and for-profit, but not public organizations. In nonprofit homes, performance declines when managers report higher regulatory expertise – better knowledge of the regulatory standards. In for-profit facilities, frequent communication with regulators lowers quality. These findings suggest that the regulated entities’ views of government regulation are central to their success, which necessitates improvements in the regulatory process

    Modeling sparging related death in animal cell bioreactors

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    Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 1998.Includes bibliographical references (p. 155-160).by Steven J. Meier.Ph.D

    Trunk sway in mildly disabled multiple sclerosis patients with and without balance impairment

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    Multiple sclerosis (MS) causes a broad range of neurological symptoms. Most common is poor balance control. However, knowledge of deficient balance control in mildly affected MS patients who are complaining of balance impairment but have normal clinical balance tests (CBT) is limited. This knowledge might provide insights into the normal and pathophysiological mechanisms underlying stance and gait. We analysed differences in trunk sway between mildly disabled MS patients with and without subjective balance impairment (SBI), all with normal CBT. The sway was measured for a battery of stance and gait balance tests (static and dynamic posturography) and compared to that of age- and sex-matched healthy subjects. Eight of 21 patients (38%) with an Expanded Disability Status Scale of 1.0-3.0 complained of SBI during daily activities. For standing on both legs with eyes closed on a normal and on a foam surface, patients in the no SBI group showed significant differences in the range of trunk roll (lateral) sway angle and velocity, compared to normal persons. Patients in the SBI group had significantly greater lateral sway than the no SBI group, and sway was also greater than normal in the pitch (anterior-posterior) direction. Sway for one-legged stance on foam was also greater in the SBI group compared to the no SBI and normal groups. We found a specific laterally directed impairment of balance in all patients, consistent with a deficit in proprioceptive processing, which was greater in the SBI group than in the no SBI group. This finding most likely explains the subjective symptoms of imbalance in patients with MS with normal CBT

    Forest elephant movement and habitat use in a tropical forest-grassland mosaic in Gabon

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    Poaching of forest elephants (Loxodonta cyclotis) for ivory has decimated their populations in Central Africa. Studying elephant movement can provide insight into habitat and resource use to reveal where, when, and why they move and guide conservation efforts. We fitted 17 forest elephants with global positioning system (GPS) collars in 2015 and 2016 in the tropical forest-grassland mosaic of the Wonga Wongué Presidential Reserve (WW), Gabon. Using the location data, we quantified movement distances, home ranges, and habitat use to examine the environmental drivers of elephant movements and predict where elephants occur spatially and temporally. Forest elephants, on average, traveled 2,840 km annually and had home ranges of 713 km2, with males covering significantly larger home ranges than females. Forest elephants demonstrated both daily and seasonal movement patterns. Daily, they moved between forest and grassland at dawn and dusk. Seasonally, they spent proportionally more time in grassland than forest during the short-wet season when grasses recruit. Forest elephants also traveled faster during the short-wet season when fruit availability was greatest, likely reflecting long, direct movements to preferred fruiting tree species. Forest elephants tended to select areas with high tree and shrub density that afford cover and browse. When villages occurred in their home ranges elephants spent a disproportionate amount of time near them, particularly in the dry season, probably for access to agricultural crops and preferred habitat. Given the importance of the grassland habitat for elephants, maintenance of the forest-grassland matrix is a conservation priority in WW. Law enforcement, outreach, and education should focus on areas of potential human-elephant conflict near villages along the borders of the reserve. GPS-tracking should be extended into multi-use areas in the peripheries of protected areas to evaluate the effects of human disturbance on elephant movements and to maintain connectivity among elephant populations in Gabon

    Radical-induced hetero-nuclear mixing and low-field 13^{13}C relaxation in solid pyruvic acid

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    Radicals serve as a source of polarization in dynamic nuclear polarization, but may also act as polarization sink, in particular at low field. Additionally, if the couplings between the electron spins and different nuclear reservoirs are stronger than any of the reservoirs’ couplings to the lattice, radicals can mediate hetero-nuclear polarization transfer. Here, we report radical-enhanced 13^{13}C relaxation in pyruvic acid doped with trityl. Up to 40 K, we find a linear carbon T1T_{1} field dependence between 5 mT and 2 T. We model the dependence quantitatively, and find that the presence of trityl accelerates direct hetero-nuclear polarization transfer at low fields, while at higher fields 13^{13}C relaxation is diffusion limited. Measurements of hetero-nuclear polarization transfer up to 600 mT confirm the predicted radical-mediated proton–carbon mixing

    Dissipation effects in spin-Hall transport of electrons and holes

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    We investigate the spin-Hall effect of both electrons and holes in semiconductors using the Kubo formula in the correct zero-frequency limit taking into account the finite momentum relaxation time of carriers in real semiconductors. This approach allows to analyze the range of validity of recent theoretical findings. In particular, the spin-Hall conductivity vanishes for vanishing spin-orbit coupling if the correct zero-frequency limit is performed.Comment: 5 pages, no figures, version to appear in Phys. Rev.

    Acute dietary zinc deficiency in rats exacerbates myocardial ischaemia-reperfusion injury through depletion of glutathione.

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    Zinc (Zn) plays an important role in maintaining the anti-oxidant status within the heart, and helps to counter the acute redox stress that occurs during myocardial ischaemia and reperfusion. Individuals with low zinc (Zn) levels are at greater risk of developing an acute myocardial infarction; however, the impact of this on the extent of myocardial injury is unknown. The present study aimed to compare the effects of dietary zinc depletion with in vitro removal of Zn (TPEN) on the outcome of acute myocardial infarction and vascular function. Male Sprague-Dawley rats were fed either a zinc adequate (ZA; 35mg Zn/kg diet) or zinc deficient (ZD; < 1mg Zn/kg diet) diet for two weeks prior to heart isolation. Perfused hearts were subjected to a thirty-minute ischaemia/two-hour reperfusion (I/R) protocol, during which time ventricular arrhythmias were recorded and after which infarct size was measured, along with markers of anti-oxidant status. In separate experiments hearts were challenged with the Zn chelator TPEN (10ÎŒM) prior to ischaemia onset. Both dietary and TPEN-induced Zn depletion significantly extended infarct size; dietary Zn depletion was associated with reduced total cardiac glutathione (GSH) levels, while TPEN decreased cardiac SOD-1 levels. TPEN, but not dietary Zn depletion also suppressed ventricular arrhythmias and depressed vascular responses to nitric oxide (NO). These findings demonstrate that both modes of zinc depletion worsen the outcome from I/R but through different mechanisms. Dietary Zn deficiency, resulting in reduced cardiac GSH, is the most appropriate model for determining the role of endogenous Zn in I/R injury

    Polarization state of the optical near-field

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    The polarization state of the optical electromagnetic field lying several nanometers above complex dielectric structures reveals the intricate light-matter interaction that occurs in this near-field zone. This information can only be extracted from an analysis of the polarization state of the detected light in the near-field. These polarization states can be calculated by different numerical methods well-suited to near--field optics. In this paper, we apply two different techniques (Localized Green Function Method and Differential Theory of Gratings) to separate each polarisation component associated with both electric and magnetic optical near-fields produced by nanometer sized objects. The analysis is carried out in two stages: in the first stage, we use a simple dipolar model to achieve insight into the physical origin of the near-field polarization state. In the second stage, we calculate accurate numerical field maps, simulating experimental near-field light detection, to supplement the data produced by analytical models. We conclude this study by demonstrating the role played by the near-field polarization in the formation of the local density of states.Comment: 9 pages, 11 figures, accepted for publication in Phys. Rev.
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