1,426 research outputs found

    SUCCEEDING WITH TRANSFORMATIONAL INITIATIVES: PRACTICAL APPROACHES FOR MANAGING CHANGE PROGRAMS

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    According to exiting literature, most change programs fail to manage and/or meet the expectations of stakeholders; leading to the failure of larger strategic organisational and transformational initiatives. Undoubtedly, change management necessitates introspective planning and responsive implementation but a failure to acknowledge and manage the external stakeholder environment will undermine these efforts. This article presents some practical frameworks for managing the delivery of change that were used collectively in different situations and contributed to the successful implementation of change programs. It does not recommend any specific approach to yield successful outcomes, but it considers a range of approaches for practitioners to take into account to assure seamless integration of programs with the formulation of overall strategy and implementation planning. Understanding the components of each program is asserted to support organisations to better understand the people and non-technology dimensions of their projects and the need to ensure effective, consultative communications to gain and maintain support for the program of change.people Management, change Management tactics

    Perturbations in a non-singular bouncing Universe

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    We complement the low-energy gravi-dilaton effective action of string theory with a non-local, general-covariant dilaton potential, and obtain homogeneous solutions describing a non-singular (bouncing-curvature) cosmology. We then compute, both analytically and numerically, the spectrum of amplified scalar and tensor perturbations, and draw some general lessons on how to extract observable consequences from pre-big bang and ekpyrotic scenarios.Comment: 14 pages in Latex style, 5 included figure

    Properties of dust in the detached shells around U Ant, DR Ser, and V644 Sco

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    Understanding the properties of dust produced during the asymptotic giant branch phase of stellar evolution is important for understanding the evolution of stars and galaxies. Recent observations of the carbon AGB star R Scl have shown that observations at far-infrared and submillimetre wavelengths can effectively constrain the grain sizes in the shell, while the total mass depends on the structure of the grains (solid vs. hollow or fluffy). We aim to constrain the properties of the dust observed in the submillimetre in the detached shells around the three carbon AGB stars U Ant, DR Ser, and V644 Sco, and to investigate the constraints on the dust masses and grain sizes provided by far-infrared and submm observations. We observed the carbon AGB stars U Ant, DR Ser, and V644 Sco at 870 micron using LABOCA on APEX. Combined with observations from the optical to far-infrared, we produced dust radiative transfer models of the spectral energy distributions (SEDs) with contributions from the stars, present-day mass-loss and detached shells. We tested the effect of different total dust masses and grain sizes on the SED, and attempted to consistently reproduce the SEDs from the optical to the submm. We derive dust masses in the shells of a few 10e-5 Msun, assuming spherical, solid grains. The best-fit grain radii are comparatively large, and indicate the presence of grains between 0.1 micron-2 micron. The LABOCA observations suffer from contamination from 12CO(3-2), and hence gives fluxes that are higher than the predicted dust emission at submm wavelengths. We investigate the effect on the best-fitting models by assuming different degrees of contamination and show that far-infrared and submillimetre observations are important to constrain the dust mass and grain sizes in the shells.Comment: Accepted by A&

    ALMA observations of the vibrationally-excited rotational CO transition v=1,J=32v=1, J=3-2 towards five AGB stars

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    We report the serendipitous detection with ALMA of the vibrationally-excited pure-rotational CO transition v=1,J=32v=1, J=3-2 towards five asymptotic giant branch (AGB) stars, oo Cet, R Aqr, R Scl, W Aql, and π1\pi^1 Gru. The observed lines are formed in the poorly-understood region located between the stellar surface and the region where the wind starts, the so-called warm molecular layer. We successfully reproduce the observed lines profiles using a simple model. We constrain the extents, densities, and kinematics of the region where the lines are produced. R Aqr and R Scl show inverse P-Cygni line profiles which indicate infall of material onto the stars. The line profiles of oo Cet and R Scl show variability. The serendipitous detection towards these five sources shows that vibrationally-excited rotational lines can be observed towards a large number of nearby AGB stars using ALMA. This opens a new possibility for the study of the innermost regions of AGB circumstellar envelopes.Comment: 6 pages, 2 figures, 2 tables, 2016MNRAS.463L..74

    Job burnout among Israeli healthcare workers during the first months of COVID-19 pandemic: The role of emotion regulation strategies and psychological distress

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    The current worldwide COVID-19 pandemic has elicited widespread concerns and stress. Arguably, healthcare workers are especially vulnerable to experience burnout during these times due to the nature of their work. Indeed, high prevalence of burnout was found among healthcare workers during the outbreak. However, the individual differences predicting burnout among healthcare workers during the pandemic have been understudied. The aim of the current study was, therefore, to identify risk and protective factors contributing to the severity of burnout among healthcare workers, above and beyond levels of current psychological distress. The survey was distributed online during the period April 13-28, 2020, approximately two months after the first COVID-19 case was identified in Israel. Ninety-eight healthcare workers completed an online survey administered cross-sectionally via the Qualtrics platform that included questionnaires assessing habitual emotion regulation strategies (i.e., trait worry, reappraisal, and suppression), psychological distress, COVID-19 related concerns, and burnout. A hierarchical linear regression analysis revealed that only trait worry and psychological distress were significant predictors of job burnout among healthcare workers. These findings highlight the role of maladaptive emotion regulation tendencies, specifically trait worry, in job burnout among healthcare workers. These findings have implications for both the assessment and treatment of healthcare workers. We discuss potential mechanisms and implications for practice

    CO and HCN isotopologue ratios in the outflows of AGB stars

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    Isotopologue line intensity ratios of circumstellar molecules have been widely used to trace the photospheric elemental isotopic ratios of evolved stars. However, depending on the molecular species and the physical conditions of the environment, the circumstellar isotopologue ratio may deviate considerably from the stellar atmospheric value. In this paper, we aim to examine how the CO and HCN abundance ratios vary radially due to chemical reactions in the outflows of AGB stars and the effect of excitation and optical depth on the resulting line intensity ratios. We find that the circumstellar 12CO/13CO can deviate from its atmospheric value by up to 25-94% and 6-60% for C- and O-type CSEs, respectively. We show that variations of the intensity of the ISRF and the gas kinetic temperature can significantly influence the CO isotopologue ratio in the outer CSEs. On the contrary, the H12CN/H13CN ratio is stable for all tested mass-loss rates. The RT modeling shows that the integrated line intensity ratio of CO of different rotational transitions varies significantly for stars with intermediate mass-loss rates due to combined chemical and excitation effects. In contrast, the excitation conditions for the both HCN isotopologues are the same. We demonstrate the importance of using the isotopologue abundance profiles from chemical models as inputs to RT models in the interpretation of isotopologue observations. Previous studies of CO isotopologue ratios are based on multi-transition data for individual sources and it is difficult to estimate the errors in the reported values due to assumptions that are not entirely correct according to this study. If anything, previous studies may have overestimated the circumstellar 12CO/13CO abundance ratio. The use of the HCN as a tracer of C isotope ratios is affected by fewer complicating problems, provided one accounts corrections for high optical depths.Comment: 14 pages, 11 figure

    Methodology to rapidly map and quantify whole-brain microvasculature in 3d

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    The role of microvasculature in the development of cerebral disorders remains ambiguous despite recent implications in ~45% of dementia cases (including Alzheimer’s) and ~20% of strokes.1 Our goal is to develop 3D, high resolution, whole-brain maps of the cerebral microvasculature. This will address the knowledge gap surrounding vasculature changes during disease progression and ultimately support the development of innovative treatment paradigms. This effort is complementary to the BRAIN Initiative’s emphasis on comprehensive neuronal mapping. To better understand the role of vasculature in the onset of cerebral pathologies, we have developed a protocol for capture, conversion and comparison of vascular structure and key characteristics in the intact mouse brain with quotidian programs. We created a novel pipeline for 3D whole-brain modeling using techniques of perfusion for vascular labeling, amendment of the iDISCO+ organ clearing protocol, light sheet microscopy (LSM), data handling and image processing. Our protocol relies on vascular labeling via retro-orbital perfusion of fluorescent Lectin-Dylight 649 (Vector Labs), which we have observed to label vasculature in a more comprehensive fashion than other dyes (i.e., lectin-FITC, DiI). It takes up to two days to achieve whole-brain clearing; whereas the iDISCO+ protocol requires the use of secondary antibodies and a timeline of weeks. In lieu of expensive software packages, such as the Filament Tracer feature in Imaris, we trace the vasculature using freeware packages that can be used for 3D reconstruction and manipulation from most personal computers (Figure 1B). Current work involves integration of our data with the Allen Brain Atlas, to merge our vascular computational data sets to an averaged frame of reference map for use by other groups. We anticipate that this approach can be used to study the relationship between microvascular structure and function with cerebral pathology and to fit mathematical models of hypoxia predictive of ischemic conditions in the brain. Please click Additional Files below to see the full abstract
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