456 research outputs found

    Cell-free prediction of protein expression costs for growing cells

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    Translating heterologous proteins places significant burden on host cells, consuming expression resources leading to slower cell growth and productivity. Yet predicting the cost of protein production for any given gene is a major challenge, as multiple processes and factors combine to determine translation efficiency. To enable prediction of the cost of gene expression in bacteria, we describe here a standard cell-free lysate assay that provides a relative measure of resource consumption when a protein coding sequence is expressed. These lysate measurements can then be used with a computational model of translation to predict the in vivo burden placed on growing E. coli cells for a variety of proteins of different functions and lengths. Using this approach, we can predict the burden of expressing multigene operons of different designs and differentiate between the fraction of burden related to gene expression compared to action of a metabolic pathway

    The Association Between an Established Chief Experience Officer Role and Hospital Patient Experience Scores

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    The healthcare industry is currently reacting to multiple stakeholders demanding improvements to the patient experience. Some healthcare organizations are implementing new management structures, i.e., the role of Chief Experience Officer (CXO). This study statistically reviewed descriptors associated with hospitals that have and have not created and filled the role of CXO and, more importantly, measured the association between the CXO role and results of patients’ perceptions of their experience of care as measured by publicly reported Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) results. This study was conducted utilizing data gather on hospitals in three states, California, Florida, and New York. The results of the study yield insight into the organization characteristics of hospitals and the market factors associated with those hospitals that have filled the CXO role. Hospitals with a formal CXO role are larger, more likely to be for profit, and operate in metro areas of these states with higher per capita income. In addition, hospitals that have a formal CXO role are also more likely to have higher HCAHPS scores as determined by the patient recommendation question as well as the hospital overall rating question included in the HCAHPS survey

    The association between an established Chief Experience Officer role and hospital patient experience scores

    Get PDF
    The healthcare industry is currently reacting to multiple stakeholders demanding improvements to the patient experience. Some healthcare organizations are implementing new management structures, i.e., the role of Chief Experience Officer (CXO). This study statistically reviewed descriptors associated with hospitals that have and have not created and filled the role of CXO and, more importantly, measured the association between the CXO role and results of patients’ perceptions of their experience of care as measured by publicly reported Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) results. This study was conducted utilizing data gather on hospitals in three states, California, Florida, and New York. The results of the study yield insight into the organization characteristics of hospitals and the market factors associated with those hospitals that have filled the CXO role. Hospitals with a formal CXO role are larger, more likely to be for profit, and operate in metro areas of these states with higher per capita income. In addition, hospitals that have a formal CXO role are also more likely to have higher HCAHPS scores as determined by the patient recommendation question as well as the hospital overall rating question included in the HCAHPS survey. Experience Framework This article is associated with the Culture & Leadership lens of The Beryl Institute Experience Framework (https://www.theberylinstitute.org/ExperienceFramework). Access other PXJ articles related to this lens. Access other resources related to this len

    An XMM-Newton Study of the Bright, Nearby Supernova Remnant G296.1-0.5

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    We present a detailed study of the supernova remnant G296.1-0.5, performed using observations with the EPIC and RGS instruments of the XMM-Newton satellite. G296.1-0.5 is a bright remnant that displays an incomplete multiple-shell morphology in both its radio and X-ray images. We use a set of observations towards G296.1-0.5, from three distinct pointings of EPIC, in order to perform a thorough spatial and spectral analysis of this remnant, and hence determine what type of progenitor gave rise to the supernova explosion, and describe the evolutionary state of the SNR. Our XMM-Newton observations establish that the spectral characteristics are consistent across the X-ray bright regions of the object, and are best described by a model of the emission from a nonequilibrium ionization collisional plasma. The study reveals that the emission from the shell is characterized by an excess of N and an underabundance of O, which is typical of wind material from red supergiant (RSG) and Wolf-Rayet (WR) stars. Additionally, we have detected transient X-ray source 2XMMi J115004.8-622442 at the edge of the SNR whose properties suggest that it is the result of stellar flare, and we discuss its nature in more detail.Comment: 10 pages, 7 figures, 3 tables. Accepted for publication in Ap

    Gap States in Dilute Magnetic Alloy Superconductors

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    We study states in the superconducting gap induced by magnetic impurities using self-consistent quantum Monte Carlo with maximum entropy and formally exact analytic continuation methods. The magnetic impurity susceptibility has different characteristics for T_{0} \alt T_{c0} and T_{0} \agt T_{c0} (T0T_{0}: Kondo temperature, Tc0T_{c0}: superconducting transition temperature) due to the crossover between a doublet and a singlet ground state. We systematically study the location and the weight of the gap states and the gap parameter as a function of T0/Tc0T_{0}/T_{c0} and the concentration of the impurities.Comment: 4 pages in ReVTeX including 4 encapsulated Postscript figure

    Diuretic activity of aqueous extract and betulin from Colliguaja integerrima in rats

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    Five known compounds were isolated from the aerial parts of Colliguaja integerrima Gillies & Hook (Euphorbiaceae). A pharmacological evaluation of the diuretic activity of the plant was carried out in isotonic saline-loaded rats. The data reported in the present work indicate that the aqueous extract of the aerial parts from C. integerrima showed a moderate diuretic activity. The urinary levels of sodium and potassium are increased by treatment with C. integerima aqueous extract. This activity could be due, in part, to the presence of betulin isolated as the major metabolite of C. integerrima.Fil: Alvarez, María E.. Universidad Nacional de San Luis; ArgentinaFil: Gil, Raul Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; ArgentinaFil: Acosta, Maria Gimena. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Química de San Luis. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Química de San Luis; ArgentinaFil: Saad, José Roberto. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Química. Area de Química Orgánica; ArgentinaFil: Borkowski, Eduardo Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto de Investigaciones en Tecnología Química. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Instituto de Investigaciones en Tecnología Química; ArgentinaFil: María, Alejandra O. M.. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Química. Area de Química Orgánica; Argentin

    A dense disk of dust around the born-again Sakurai's object

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    In 1996, Sakurai's object (V4334 Sgr) suddenly brightened in the centre of a faint Planetary Nebula (PN). This very rare event was interpreted as the reignition of a hot white dwarf that caused a rapid evolution back to the cool giant phase. From 1998 on, a copious amount of dust has formed continuously, screening out the star which has remained embedded in this expanding high optical depth envelope. The new observations, reported here, are used to study the morphology of the circumstellar dust in order to investigate the hypothesis that Sakurai's Object is surrounded by a thick spherical envelope of dust. We have obtained unprecedented, high-angular resolution spectro-interferometric observations, taken with the mid-IR interferometer MIDI/VLTI, which resolve the dust envelope of Sakurai's object. We report the discovery of a unexpectedly compact (30 x 40 milliarcsec, 105 x 140 AU assuming a distance of 3.5 kpc), highly inclined, dust disk. We used Monte Carlo radiative-transfer simulations of a stratified disk to constrain its geometric and physical parameters, although such a model is only a rough approximation of the rapidly evolving dust structure. Even though the fits are not fully satisfactory, some useful and robust constraints can be inferred. The disk inclination is estimated to be 75+/-3 degree with a large scale height of 47+/-7 AU. The dust mass of the disk is estimated to be 6 10^{-5} solar mass. The major axis of the disk (132+/-3 degree) is aligned with an asymmetry seen in the old PN that was re-investigated as part of this study. This implies that the mechanism responsible for shaping the dust envelope surrounding Sakurai's object was already at work when the old PN formed.Comment: A&A Letter, accepte

    Generation of radiative knots in a randomly pulsed protostellar jet I. Dynamics and energetics

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    HH objects are characterized by a complex knotty morphology detected mainly along the axis of protostellar jets in a wide range of bands. Evidence of interactions between knots formed in different epochs have been found, suggesting that jets may result from the ejection of plasma blobs from the source. We aim at investigating the physical mechanism leading to the irregular knotty structure observed in jets in different bands and the complex interactions occurring among blobs of plasma ejected from the stellar source. We perform 2D axisymmetric HD simulations of a randomly ejected pulsed jet. The jet consists of a train of blobs which ram with supersonic speed into the ambient medium. The initial random velocity of each blob follows an exponential distribution. We explore the ejection rate parameter to derive constraints on the physical properties of protostellar jets by comparison of model results with observations. Our model takes into account radiative losses and thermal conduction. We find that the mutual interactions of blobs ejected at different epochs and with different speed lead to a variety of plasma components not described by current models. The main features characterizing the random pulsed jet scenario are: single high speed knots, showing a measurable proper motion in nice agreement with observations; irregular chains of knots aligned along the jet axis and possibly interacting with each other; reverse shocks interacting with outgoing knots; oblique shocks produced by the reflection of shocks at the jet cocoon. All these structures concur to determine the morphology of the jet in different bands. We also find that the thermal conduction plays a crucial role in damping out HD instabilities that would develop within the cocoon and that contribute to the jet breaking.Comment: 10 pages, 10 figures, accepted for publication in A&
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