54 research outputs found
Wage inequality, segregation by skill and the price of capital in an assignment model
Some pieces of empirical evidence suggest that in the U.S., over the last few decades, (i) wage inequality between-plants has risen much more than wage inequality within-plants and (ii) there has been an increase in the segregation of workers by skill into separate plants. This paper presents a frictionless assignment model in which these two features can be explained simultaneously as the result of the decline in the relative price of capital. Additional implications of the model regarding the skill premium and the dispersion in labor productivity across plants are also consistent with the empirical evidence. [resumen de autor
Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study
Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research
The7Li(d, p)8Li reaction in inverse kinematics at 5.44 MeV/u
New data are presented for the 7Li(d, p)8Li stripping reaction which, together with previously reported elastic scattering data taken in the same experiment, provide a coherent set. These data, plus existing measurements of the elastic scattering and stripping at 6MeV/u were analysed within the same coupled reaction channels scheme. Good descriptions of the stripping data to the 0.0MeV and 0.98MeV states of 8Li were obtained using a set of ^8Li| ^7Li + n\u232a overlaps taken from the literature, provided that the elastic scattering was also well described. Multi-step reaction paths made significant contributions to the description of the larger angle data. The asymptotic normalisation coefficients are compared with previous determinations
Near barrier scattering of 8He on 208Pb
The exotic nucleus He-8 is investigated by means of the measurement of the angular distributions of the elastic channel and the He-6 and He-4 fragment yields produced in the collision with a Pb-208 target at two energies around the Coulomb barrier, 16 and 22 MeV. The experiment was performed at the GANIL-SPIRAL facility, with the aim of extracting information about the structure of He-8 and the relevant reaction mechanisms. In this contribution, details of the experimental setup and preliminary data on elastic cross sections are reported
Global description of the Li 7 +p reaction at 5.44 MeV/u in a continuum-discretized coupled-channels approach
The complete set of open channels for the 7Li+p system, namely elastic scattering, inelastic scattering, breakup, the 7Li+p\u21927Be+n charge exchange reaction, and the 7Li+p\u21924He+4He reaction, was measured in the same experiment in inverse kinematics at an energy of 5.44 MeV/u. Data were also obtained for the charge exchange reaction at energies of 5.0 and 3.57 MeV/u. The elastic and inelastic scattering and breakup data were reported previously and are reviewed here and, together with the new data for the other two reactions, are discussed coherently within the same continuum-discretized coupled-channels model framework
Study of the near-barrier scattering of 8He on 208Pb
The structure and dynamics of 8He have been studied through the collision process with a 208Pb target at energies of 22 and 16 MeV, above and below the Coulomb barrier, respectively. The energy and angular distributions of the elastically scattered 8He and the 6,4He fragments were measured. In this paper, we discuss the method used to determine the effective position of the beam spot on the reaction target and the scattering and solid angles of each pixel of the detector array
Breakup of Li 6 +p at near-barrier energies and the effect on elastic scattering
International audienceExclusive breakup measurements have been performed for the Li6+p system in inverse kinematics at Li6 incident energies of 25 and 29 MeV. The results are considered in the Continuum Discretized Coupled-Channels framework, together with elastic scattering data at 16, 20, 25, and 29 MeV, obtained simultaneously in the same experiment and reported previously. Good agreement between data and theory is observed, interpreted as evidence for strong coupling to the continuum. The direct and sequential (via the Li631+ resonance) breakup cross sections are found to be equally large at the higher incident energies but the dominant effect on the elastic scattering is due to coupling to the sequential breakup. This effect remains dominant even at the lowest energy of 16 MeV, despite the negligible cross section for excitation of the resonance at this low incident energy
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