1,096 research outputs found
Managing Opioid-Tolerant Patients in the Perioperative Surgical Home.
Management of acute postoperative pain is important to decrease perioperative morbidity and improve patient satisfaction. Opioids are associated with potential adverse events that may lead to significant risk. Uncontrolled pain is a risk factor in the transformation of acute pain to chronic pain. Balancing these issues can be especially challenging in opioid-tolerant patients undergoing surgery, for whom rapidly escalating opioid doses in an effort to control pain can be associated with increased complications. In the perioperative surgical home model, anesthesiologists are positioned to coordinate a comprehensive perioperative analgesic plan that begins with the preoperative assessment and continues through discharge
Energy density functional on a microscopic basis
In recent years impressive progress has been made in the development of
highly accurate energy density functionals, which allow to treat medium-heavy
nuclei. In this approach one tries to describe not only the ground state but
also the first relevant excited states. In general, higher accuracy requires a
larger set of parameters, which must be carefully chosen to avoid redundancy.
Following this line of development, it is unavoidable that the connection of
the functional with the bare nucleon-nucleon interaction becomes more and more
elusive. In principle, the construction of a density functional from a density
matrix expansion based on the effective nucleon-nucleon interaction is
possible, and indeed the approach has been followed by few authors. However, to
what extent a density functional based on such a microscopic approach can reach
the accuracy of the fully phenomenological ones remains an open question. A
related question is to establish which part of a functional can be actually
derived by a microscopic approach and which part, on the contrary, must be left
as purely phenomenological. In this paper we discuss the main problems that are
encountered when the microscopic approach is followed. To this purpose we will
use the method we have recently introduced to illustrate the different aspects
of these problems. In particular we will discuss the possible connection of the
density functional with the nuclear matter Equation of State and the distinct
features of finite size effects proper of nuclei.Comment: 20 pages, 6 figures,Contribution to J. Phys G, Special Issue, Focus
Section: Open Problems in Nuclear Structur
On the Differential Geometry of
The differential calculus on the quantum supergroup GL was
introduced by Schmidke {\it et al}. (1990 {\it Z. Phys. C} {\bf 48} 249). We
construct a differential calculus on the quantum supergroup GL in a
different way and we obtain its quantum superalgebra. The main structures are
derived without an R-matrix. It is seen that the found results can be written
with help of a matrix Comment: 14 page
Equation-of-state dependence of the gravitational-wave signal from the ring-down phase of neutron-star mergers
Neutron-star (NS) merger simulations are conducted for 38 representative
microphysical descriptions of high-density matter in order to explore the
equation-of-state dependence of the postmerger ring-down phase. The formation
of a deformed, oscillating, differentially rotating very massive NS is the
typical outcome of the coalescence of two stars with 1.35 for most
candidate EoSs. The oscillations of this object imprint a pronounced peak in
the gravitational-wave (GW) spectra, which is used to characterize the emission
for a given model. The peak frequency of this postmerger GW signal correlates
very well with the radii of nonrotating NSs, and thus allows to constrain the
high-density EoS by a GW detection. In the case of 1.35-1.35
mergers the peak frequency scales particularly well with the radius of a NS
with 1.6 , where the maximum deviation from this correlation is only
60 meters for fully microphysical EoSs which are compatible with NS
observations. Combined with the uncertainty in the determination of the peak
frequency it appears likely that a GW detection can measure the radius of a 1.6
NS with an accuracy of about 100 to 200 meters. We also uncover
relations of the peak frequency with the radii of nonrotating NSs with 1.35
or 1.8 , with the radius or the central energy density
of the maximum-mass Tolman-Oppenheimer-Volkoff configuration, and with the
pressure or sound speed at a fiducial rest-mass density of about twice nuclear
saturation density. Furthermore, it is found that a determination of the
dominant postmerger GW frequency can provide an upper limit for the maximum
mass of nonrotating NSs. The prospects for a detection of the postmerger GW
signal and a determination of the dominant GW frequency are estimated to be in
the range of 0.015 to 1.2 events per year with the upcoming Advanced LIGO
detector.Comment: 29 pages, 28 figures, accepted for publication in Phys. Rev.
Low-Rank Decompositions of Three-Nucleon Forces via Randomized Projections
Ab initio calculations for nuclei and nuclear matter are limited by the
computational requirements of processing large data objects. In this work, we
develop low-rank singular value decompositions for chiral three-nucleon
interactions, which dominate these limitations. In order to handle the large
dimensions in representing three-body operators, we use randomized
decomposition techniques. We study in detail the sensitivity of different
three-nucleon topologies to low-rank matrix factorizations. The developed
low-rank three-nucleon interactions are benchmarked in Faddeev calculations of
the triton and ab initio calculations of medium-mass nuclei. Exploiting
low-rank properties of nuclear interactions will be particularly important for
the extension of ab initio studies to heavier and deformed systems, where
storage requirements will exceed the computational capacities of the most
advanced high-performance-computing facilities.Comment: 7 pages, 4 figure
First direct mass-measurement of the two-neutron halo nucleus 6He and improved mass for the four-neutron halo 8He
The first direct mass-measurement of He has been performed with the
TITAN Penning trap mass spectrometer at the ISAC facility. In addition, the
mass of He was determined with improved precision over our previous
measurement. The obtained masses are (He) = 6.018 885 883(57) u and
(He) = 8.033 934 44(11) u. The He value shows a deviation from
the literature of 4. With these new mass values and the previously
measured atomic isotope shifts we obtain charge radii of 2.060(8) fm and
1.959(16) fm for He and He respectively. We present a detailed
comparison to nuclear theory for He, including new hyperspherical harmonics
results. A correlation plot of the point-proton radius with the two-neutron
separation energy demonstrates clearly the importance of three-nucleon forces.Comment: 4 pages, 2 figure
A multifaceted quality improvement project improves intraoperative redosing of surgical antimicrobial prophylaxis during pediatric surgery
BackgroundAccurate intraoperative antibiotic redosing contributes to prevention of surgical site infections in pediatric patients. Ensuring compliance with evolving national guidelines of weightâbased, intraoperative redosing of antibiotics is challenging to pediatric anesthesiologists.AimsOur primary aim was to increase compliance of antibiotic redoses at the appropriate time and appropriate weightâbased dose to 70%. Secondary aims included a subset analysis of time compliance and dose compliance individually, and compliance based on order entry method of the first dose (verbal or electronic).MethodsAt a freestanding, academic pediatric hospital, we reviewed surgical cases between May 1, 2014, and October 31, 2017 requiring antibiotic redoses. After an institutional change in cefazolin dosing in May 2015, phased interventions to improve compliance included electronic countermeasures to display previous and next dose timing, an alert 5Â minutes prior to next dose, and weightâbased dose recommendation (September 2015). Physical countermeasures include badge cards, posting of guidelines, and updates to housestaff manual (September 2015). Statistical process control charts were used to assess overall antibiotic redose compliance, time compliance, and dose compliance. The chiâsquare test was used to analyze group differences.ResultsA total of 3015 antibiotic redoses were administered during 2341 operative cases between May 1, 2014, and October 31, 2017. Mean monthly compliance with redosing was 4.3% (May 2014âApril 2015) and 73% (November 2015âOctober 2017) (PÂ <Â 0.001). Doseâonly compliance increased from 76% to 89% (PÂ <Â 0.001), and timeâonly compliance increased from 4.9% to 82% (PÂ <Â 0.001). After implementation of countermeasures, electronic order entry compared with verbal order was associated with higher dose compliance, 90% vs 86% (PÂ =Â 0.015).ConclusionThis quality improvement project, utilizing electronic and physical interventions, was effective in improving overall prophylactic antibiotic redosing compliance in accordance with institutional redosing guidelines.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/150557/1/pan13651_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/150557/2/pan13651.pd
The current state of antifungal stewardship among pediatric antimicrobial stewardship programs
OBJECTIVE: To characterize the current state of antifungal stewardship practices and perceptions of antifungal use among pediatric antimicrobial stewardship programs (ASPs).
DESIGN: We developed and distributed an electronic survey, which included 17 closed-ended questions about institutional antifungal stewardship practices and perceptions, among pediatric ASPs.
PARTICIPANTS: ASP physicians and pharmacists of 74 hospitals participating in the multicenter Sharing Antimicrobial Reports for Pediatric Stewardship (SHARPS) Collaborative.
RESULTS: We sent surveys to 74 hospitals and received 68 unique responses, for a response rate of 92%. Overall, 63 of 68 the respondent ASPs (93%) reported that they conduct 1 or more antifungal stewardship activities. Of these 68 hospital ASPs, 43 (63%) perform prospective audit and feedback (PAF) of antifungals. The most common reasons reported for not performing PAF of antifungals were not enough time or resources (19 of 25, 76%) and minimal institutional antifungal use (6 of 25, 24%). Also, 52 hospitals (76%) require preauthorization for 1 or more antifungal agents. The most commonly restricted antifungals were isavuconazole (42 of 52 hospitals, 80%) and posaconazole (39 of 52 hospitals, 75%). Furthermore, 33 ASPs (48%) agreed or strongly agreed that antifungals are inappropriately used at their institution, and only 25 of 68 (37%) of ASPs felt very confident making recommendations about antifungals.
CONCLUSIONS: Most pediatric ASPs steward antifungals, but the strategies employed are highly variable across surveyed institutions. Although nearly half of respondents identified inappropriate antifungal use as a problem at their institution, most ASPs do not feel confident making recommendations about antifungals. Future studies are needed to determine the rate of inappropriate antifungal use and the best antifungal stewardship strategies
Ground-State Electromagnetic Moments of Calcium Isotopes
High-resolution bunched-beam collinear laser spectroscopy was used to measure
the optical hyperfine spectra of the Ca isotopes. The ground state
magnetic moments of Ca and quadrupole moments of Ca were
measured for the first time, and the Ca ground state spin was
determined in a model-independent way. Our results provide a critical test of
modern nuclear theories based on shell-model calculations using
phenomenological as well as microscopic interactions. The results for the
neutron-rich isotopes are in excellent agreement with predictions using
interactions derived from chiral effective field theory including three-nucleon
forces, while lighter isotopes illustrate the presence of particle-hole
excitations of the Ca core in their ground state.Comment: Accepted as a Rapid Communication in Physical Review
Renormalization group and Fermi liquid theory for many-nucleon systems
We discuss renormalization group approaches to strongly interacting Fermi
systems, in the context of Landau's theory of Fermi liquids and functional
methods, and their application to neutron matter.Comment: 40 pages, 23 figures, updated lectures given at ECT*, to appear in
Springer Lecture Notes in Physic
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