1,121 research outputs found

    Bose-Einstein Correlations and Sonoluminescence

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    Sonoluminescence may be studied in detail by intensity correlations among the emitted photons. As an example, we discuss an experiment to measure the size of the light-emitting region by the Hanbury Brown-Twiss effect. We show that single bubble sonoluminescence is almost ideally suited for study by this method and that plausible values for the physical parameters are within easy experimental reach. A sequence of two and higher order photon correlation experiments is outlined.Comment: Latex File, 8 pages, Postscript file with 2 figs. attache

    Analgesic prescribing trends in a national sample of older veterans with osteoarthritis: 2012-2017

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    Few investigations examine patterns of opioid and nonopioid analgesic prescribing and concurrent pain intensity ratings before and after institution of safer prescribing programs such as the October 2013 Veterans Health Administration system-wide Opioid Safety Initiative (OSI) implementation. We conducted a quasi-experimental pre–post observational study of all older U.S. veterans (≄50 years old) with osteoarthritis of the knee or hip. All associated outpatient analgesic prescriptions and outpatient pain intensity ratings from January 1, 2012 to December 31, 2016, were analyzed with segmented regression of interrupted time series. Standardized monthly rates for each analgesic class (total, opioid, nonsteroidal anti-inflammatory drug, acetaminophen, and other study analgesics) were analyzed with segmented negative binomial regression models with overall slope, step, and slope change. Similarly, segmented linear regression was used to analyze pain intensity ratings and percentage of those reporting pain. All models were additionally adjusted for age, sex, and race. Before OSI implementation, total analgesic prescriptions showed a steady rise, abruptly decreasing to a flat trajectory after OSI implementation. This trend was primarily due to a decrease in opioid prescribing after OSI. Total prescribing after OSI implementation was partially compensated by continuing increased prescribing of other study analgesics as well as a significant rise in acetaminophen prescriptions (post-OSI). No changes in nonsteroidal anti-inflammatory drug prescribing were seen. A small rise in the percentage of those reporting pain but not mean pain intensity ratings continued over the study period with no changes associated with OSI. Changes in analgesic prescribing trends were not paralleled by changes in reported pain intensity for older veterans with osteoarthritis

    Shape parametrization for liquid-drop studies

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    We present a new method for defining axially symmetric shapes which is particularly appropriate for describing elongated and multineck configurations. This shape parametrization is used to describe the static properties of incompressible, charged liquid drops. In particular, we calculate the properties of binary-fission saddle points and compare these with results using other methods. We also present the geometrical properties and normal mode analyses of the two-and three-necked saddle-point families

    Factors Associated with Parental Involvement in their Child\u27s Education

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    After 4 decades and a large body of research on children\u27s academic success, there is still a need to understand how to increase children\u27s academic performance. Researchers agree that the key component to elementary school children\u27s academic success is parental involvement. However, little is known on how to increase parental involvement and the characteristics of the parents who participate in their children\u27s education. This quantitative study examined 2 parental characteristics, parents\u27 internal attachment patterns and parenting styles, and their relationship with parental involvement and children\u27s academic success. Bowlby\u27s theory of attachment and Baumrind\u27s parenting typologies served as the theoretical framework. Parents who have a child between 7 and 11 years of age (n = 85) from two different western cities completed an online survey via Survey Monkey that consisted of Relationship Scales Questionnaire, Parenting Style Scale, the Parent and School Survey, and a Grade Questionnaire. Linear regression was used to determine if parental involvement mediates the relationship between parents\u27 internal attachment patterns (independent variable Model A) and children\u27s academic success and if parental involvement mediates the relationship between parenting styles (independent variable Model B) and children\u27s academic success. The study found that parental involvement does mediate the relationship between parents\u27 internal attachment patterns and children\u27s academic success. Parental involvement also mediates the relationship between parenting styles and children\u27s academic success. Positive social change includes having a better understanding for increasing academic performance for elementary school children

    Sonoluminescence: Two-photon correlations as a test of thermality

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    In this Letter we propose a fundamental test for probing the thermal nature of the spectrum emitted by sonoluminescence. We show that two-photon correlations can in principle discriminate between real thermal light and the quasi-thermal squeezed-state photons typical of models based on the dynamic Casimir effect. Two-photon correlations provide a powerful experimental test for various classes of sonoluminescence models.Comment: 6 pages, revtex 3; revised to include more discussion of finite volume effects; physics conclusions unchanged; to appear in Physics Letters

    Evaporation of light particles from a hot, deformed and rotating nucleus

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    The dependence of the transmission coefficient on the deformation, the collective rotation and excitation energy of the compound nucleus emitting light particles is introduced in the framework of Wei{\ss}kopf's evaporation theory. The competition between fission and particle evaporation is treated by a~Langevin equation for the fission variable coupled to the emission process. Detailed calculations are presented on the decay of different Gd and Yb isotopes at an excitation energy of about 250~MeV. These calculations demonstrate the importance of the effects of nuclear deformation and of the initial spin distribution on the evaporation.Comment: 22 pages in LaTeX and 26 PS-figures include

    Antibiotic de-escalation experience in the setting of emergency department: A retrospective, observational study

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    Background: Antimicrobial de-escalation (ADE) is a part of antimicrobial stewardship strategies aiming to minimize unnecessary or inappropriate antibiotic exposure to decrease the rate of antimicrobial resistance. Information regarding the effectiveness and safety of ADE in the setting of emergency medicine wards (EMW) is lacking. Methods: Adult patients admitted to EMW and receiving empiric antimicrobial treatment were retrospectively studied. The primary outcome was the rate and timing of ADE. Secondary outcomes included factors associated with early ADE, length of stay, and in-hospital mortality. Results: A total of 336 patients were studied. An initial regimen combining two agents was prescribed in 54.8%. Ureidopenicillins and carbapenems were the most frequently empiric treatment prescribed (25.1% and 13.6%). The rate of the appropriateness of prescribing was 58.3%. De-escalation was performed in 111 (33%) patients. Patients received a successful de-escalation on day 2 (21%), 3 (23%), and 5 (56%). The overall in-hospital mortality was 21%, and it was significantly lower among the de-escalation group than the continuation group (16% vs 25% p = 0.003). In multivariate analysis, de-escalation strategies as well as appropriate empiric and targeted therapy were associated with reduced mortality. Conclusions: ADE appears safe and effective in the setting of EMWs despite that further research is warranted to confirm these findings

    Light-particle emission from the fissioning nuclei 126Ba, 188Pt and (266,272,278)/110: theoretical predictions and experimental results

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    We present a comparison of our model treating fission dynamics in conjunction with light-particle (n, p, alpha) evaporation with the available experimental data for the nuclei 126Ba, 188Pt and three isotopes of the element Z=110. The dynamics of the symmetric fission process is described through the solution of a classical Langevin equation for a single collective variable characterizing the nuclear deformation along the fission path. A microscopic approach is used to evaluate the emission rates for pre-fission light particles. Entrance-channel effects are taken into account by generating an initial spin distribution of the compound nucleus formed by the fusion of two deformed nuclei with different relative orientations
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