1,874 research outputs found

    ILR Impact Brief – Supervisor Support, Employee Control Help NYC Firefighters Cope with 9/11

    Get PDF
    Although individuals often work in groups and groups function within a larger environment, researchers have rarely examined the effect of context on employees’ emotions, attitudes, or behaviors. This study uses the World Trade Center attack to generate and test a context theory concerning the impact on first responders of their involvement in a catastrophic event. The model details the way in which the climate (support from supervisors and employee control over the work environment) within discrete engine and ladder companies (work units) moderates the relationship between emergency response to the attack (the stressor) and the resulting emotional strain on the firefighters. Prior studies have shown that people’s exposure to critical incidents is associated with depression, anxiety, and stress that may begin immediately or surface months later. The severity of individual reactions varies and researchers have proposed several explanatory theories, including biological and psychological factors, the way people mentally process their experiences, and the array of physical and social/emotional resources at their disposal. The authors here draw on the latter two theoretical frameworks to formulate and test several hypotheses that help explain why New York City firefighters involved in 9/11 felt more or less emotionally wrought 18 months after the attack

    Postcolonial Entanglement: How the Carnivalesque Links Toni Morrison and Chris Abani in Disruptive Dialogue

    Get PDF
    This critical analysis of Toni Morrison’s Beloved (1987) and Chris Abani’s The Secret History of Las Vegas (2014) utilizes a postcolonial carnivalesque critical lens, informed by Lokangaka Losambe’s innovative reinterpretation of Mikhail Bakhtin’s carnival for application to postcolonial texts. I pay particular attention to moments in these two texts in which inversions of “order” occur and analyze how these moments build towards the culmination of resistance by societally-marginalized figures. In tracing Morrison and Abani’s reliance upon carnival disruption in texts revolving around institutional inequality, I hope to illustrate how the literary device of the carnival aligns with postcoloniality, and how this alignment inherently links two texts published twenty-seven years apart in an important conversation

    Demixing kinetics of phase separated polymer solutions in microgravity

    Get PDF
    Phase separated solutions of two neutral polymers in buffer provide a useful and versatile medium for the partition separation of biological cells. However, the efficiency of such separations is orders of magnitude lower than the thermodynamic limit. To test the hypothesis that this inefficiency is at least partially due to the convection and sedimentation that occur during the gravity driven demixing that follows introduction of cells to the systems, a series of experiments were begun aimed at performing cell partition in a low g environment. Demixing of isopycnic three polymer solvent systems was studied, experiments were performed on KC-135 aircraft and one shuttle middeck experiment was completed. Analysis of the results of these experiments and comparisons with the predictions of scaling relations for the dependence of phase domain size on time, derived for a number of possible demixing mechanisms, are presented

    Separation of biological materials in microgravity

    Get PDF
    Partition in aqueous two phase polymer systems is a potentially useful procedure in downstream processing of both molecular and particulate biomaterials. The potential efficiency of the process for particle and cell isolations is much higher than the useful levels already achieved. Space provides a unique environment in which to test the hypothesis that convection and settling phenomena degrade the performance of the partition process. The initial space experiment in a series of tests of this hypothesis is described

    Activin A inhibits MPTP and LPS-induced increases in inflammatory cell populations and loss of dopamine neurons in the mouse midbrain in Vivo

    Full text link
    © 2017 Stayte et al. Parkinson's disease is a chronic neurodegenerative disease characterized by a significant loss of dopaminergic neurons within the substantia nigra pars compacta region and a subsequent loss of dopamine within the striatum. A promising avenue of research has been the administration of growth factors to promote the survival of remaining midbrain neurons, although the mechanism by which they provide neuroprotection is not understood. Activin A, a member of the transforming growth factor ÎČ superfamily, has been shown to be a potent anti-inflammatory following acute brain injury and has been demonstrated to play a role in the neuroprotection of midbrain neurons against MPP+-induced degeneration in vitro. We hypothesized that activin A may offer similar anti-inflammatory and neuroprotective effects in in vivo mouse models of Parkinson's disease. We found that activin A significantly attenuated the inflammatory response induced by both MPTP and intranigral administration of lipopolysaccharide in C57BL/6 mice. We found that administration of activin A promoted survival of dopaminergic and total neuron populations in the pars compacta region both 8 days and 8 weeks after MPTP-induced degeneration. Surprisingly, no corresponding protection of striatal dopamine levels was found. Furthermore, activin A failed to protect against loss of striatal dopamine transporter expression in the striatum, suggesting the neuroprotective action of activin A may be localized to the substantia nigra. Together, these results provide the first evidence that activin A exerts potent neuroprotection and anti-inflammatory effects in the MPTP and lipopolysaccharide mouse models of Parkinson's disease

    Validation of the Swiss methane emission inventory by atmospheric observations and inverse modelling

    Get PDF
    Atmospheric inverse modelling has the potential to provide observation-based estimates of greenhouse gas emissions at the country scale, thereby allowing for an independent validation of national emission inventories. Here, we present a regional-scale inverse modelling study to quantify the emissions of methane (CH4_{4}) from Switzerland, making use of the newly established CarboCount-CH measurement network and a high-resolution Lagrangian transport model. In our reference inversion, prior emissions were taken from the “bottom-up” Swiss Greenhouse Gas Inventory (SGHGI) as published by the Swiss Federal Office for the Environment in 2014 for the year 2012. Overall we estimate national CH4_{4} emissions to be 196 ± 18 Ggyr−1^{-1} for the year 2013 (1σ uncertainty). This result is in close agreement with the recently revised SGHGI estimate of 206 ± 33 Ggyr−1^{-1} as reported in 2015 for the year 2012. Results from sensitivity inversions using alternative prior emissions, uncertainty covariance settings, large-scale background mole fractions, two different inverse algorithms (Bayesian and extended Kalman filter), and two different transport models confirm the robustness and independent character of our estimate. According to the latest SGHGI estimate the main CH4_{4} source categories in Switzerland are agriculture (78 %), waste handling (15 %) and natural gas distribution and combustion (6 %). The spatial distribution and seasonal variability of our posterior emissions suggest an overestimation of agricultural CH4_{4} emissions by 10 to 20% in the most recent SGHGI, which is likely due to an overestimation of emissions from manure handling. Urban areas do not appear as emission hotspots in our posterior results, suggesting that leakages from natural gas distribution are only a minor source of CH4_{4} in Switzerland. This is consistent with rather low emissions of 8.4 Ggyr−1^{-1} reported by the SGHGI but inconsistent with the much higher value of 32 Ggyr−1^{-1} implied by the EDGARv4.2 inventory for this sector. Increased CH4_{4} emissions (up to 30% compared to the prior) were deduced for the northeastern parts of Switzerland. This feature was common to most sensitivity inversions, which is a strong indicator that it is a real feature and not an artefact of the transport model and the inversion system. However, it was not possible to assign an unambiguous source process to the region. The observations of the CarboCount-CH network provided invaluable and independent information for the validation of the national bottom-up inventory. Similar systems need to be sustained to provide independent monitoring of future climate agreements

    Signaling in Secret: Pay-for-Performance and the Incentive and Sorting Effects of Pay Secrecy

    Get PDF
    Key Findings: Pay secrecy adversely impacts individual task performance because it weakens the perception that an increase in performance will be accompanied by increase in pay; Pay secrecy is associated with a decrease in employee performance and retention in pay-for-performance systems, which measure performance using relative (i.e., peer-ranked) criteria rather than an absolute scale (see Figure 2 on page 5); High performing employees tend to be most sensitive to negative pay-for- performance perceptions; There are many signals embedded within HR policies and practices, which can influence employees’ perception of workplace uncertainty/inequity and impact their performance and turnover intentions; and When pay transparency is impractical, organizations may benefit from introducing partial pay openness to mitigate these effects on employee performance and retention
    • 

    corecore