2,115 research outputs found

    Designing the ideal perioperative pain management plan starts with multimodal analgesia.

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    Multimodal analgesia is defined as the use of more than one pharmacological class of analgesic medication targeting different receptors along the pain pathway with the goal of improving analgesia while reducing individual class-related side effects. Evidence today supports the routine use of multimodal analgesia in the perioperative period to eliminate the over-reliance on opioids for pain control and to reduce opioid-related adverse events. A multimodal analgesic protocol should be surgery-specific, functioning more like a checklist than a recipe, with options to tailor to the individual patient. Elements of this protocol may include opioids, non-opioid systemic analgesics like acetaminophen, non-steroidal anti-inflammatory drugs, gabapentinoids, ketamine, and local anesthetics administered by infiltration, regional block, or the intravenous route. While implementation of multimodal analgesic protocols perioperatively is recommended as an intervention to decrease the prevalence of long-term opioid use following surgery, the concurrent crisis of drug shortages presents an additional challenge. Anesthesiologists and acute pain medicine specialists will need to advocate locally and nationally to ensure a steady supply of analgesic medications and in-class alternatives for their patients\u27 perioperative pain management

    From low-momentum interactions to nuclear structure

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    We present an overview of low-momentum two-nucleon and many-body interactions and their use in calculations of nuclei and infinite matter. The softening of phenomenological and effective field theory (EFT) potentials by renormalization group (RG) transformations that decouple low and high momenta leads to greatly enhanced convergence in few- and many-body systems while maintaining a decreasing hierarchy of many-body forces. This review surveys the RG-based technology and results, discusses the connections to chiral EFT, and clarifies various misconceptions.Comment: 76 pages, 57 figures, two figures updated, published versio

    Low-momentum interactions for nuclei

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    We show how the renormalization group is used to construct a low-momentum nucleon-nucleon interaction V_{low k}, which unifies all potential models used in nuclear structure calculations. V_{low k} can be directly applied to the nuclear shell model or to nucleonic matter without a G matrix resummation. It is argued that V_{low k} parameterizes a high-order chiral effective field theory two-nucleon force. We use cutoff dependence as a tool to assess the error in the truncation of nuclear forces to two-nucleon interactions and introduce a low-momentum three-nucleon force, which regulates A=3,4 binding energies. The adjusted three-nucleon interaction is perturbative for small cutoffs. In contrast to other precision interactions, the error due to missing many-body forces can be estimated, when V_{low k} and the corresponding three-nucleon force are used in nuclear structure calculations and the cutoff is varied.Comment: 10 pages, 5 figures, talk at INT workshop on Nuclear Forces and the Quantum Many-Body Problem, Seattle, October 200

    Are low-energy nuclear observables sensitive to high-energy phase shifts?

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    Conventional nucleon-nucleon potentials with strong short-range repulsion require contributions from high-momentum wave function components even for low-energy observables such as the deuteron binding energy. This can lead to the misconception that reproducing high-energy phase shifts is important for such observables. Interactions derived via the similarity renormalization group decouple high-energy and low-energy physics while preserving the phase shifts from the starting potential. They are used to show that high-momentum components (and high-energy phase shifts) can be set to zero when using low-momentum interactions, without losing information relevant for low-energy observables.Comment: 13 pages, 5 figures; reference and acknowledgment adde

    How should one formulate, extract, and interpret `non-observables' for nuclei?

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    Nuclear observables such as binding energies and cross sections can be directly measured. Other physically useful quantities, such as spectroscopic factors, are related to measured quantities by a convolution whose decomposition is not unique. Can a framework for these nuclear structure `non-observables' be formulated systematically so that they can be extracted from experiment with known uncertainties and calculated with consistent theory? Parton distribution functions in hadrons serve as an illustrative example of how this can be done. A systematic framework is also needed to address questions of interpretation, such as whether short-range correlations are important for nuclear structure.Comment: 7 pages. Contribution to the "Focus issue on Open Problems in Nuclear Structure", Journal of Physics

    Managing Prolonged Pain After Surgery: Examining the Role of Opioids.

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    A notable minority of patients experience persistent postsurgical pain and some of these patients consequently have prolonged exposure to opioids. Risk factors for prolonged opioid use after surgery include preoperative opioid use, anxiety, substance abuse, and alcohol abuse. The window to intervene and potentially prevent persistent opioid use after surgery is short and may best be accomplished by both surgeon and anesthesiologist working together. Anesthesiologists in particular are well positioned in the perioperative surgical home model to affect multiple aspects of the perioperative experience, including tailoring intraoperative medications and providing consultation for possible discharge analgesic regimens that can help minimize opioid use. Multimodal analgesia protocols reduce opioid consumption and thereby reduce exposure to opioids and theoretically the risk of persistent use. Regional anesthesia and analgesia techniques also reduce opioid consumption. Although many patients will recover without difficulty, the small minority who do not should receive customized care which may involve multiple office visits or consultation of a pain specialist. Enhanced recovery pathways are useful in optimizing outcomes after surgery

    Effects of Magnesium Sulfate, Digestate and Other Inorganic Nutrients on the Phototrophic Growth of the Green Microalga Scenedesmus Dimorphus

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    The individual components of the growth media, notably magnesium, have a profound impact on the growth and lipid production of the green microalgae, Scenedesmus dimorphus. The goal of this work was to investigate these effects and explain the causes via multiple experiments. It is important to understand the aspects of algal growth because they have a significant impact on the commercial viability of microalgal lipids as a potential feedstock for biofuel production. Digestate, derived from bovine waste and a potential cost effective nutrient replacement for conventional media types, was found to maximize growth and lipid concentration in S. dimorphus at 1.25 and 1.75 in water respectively and that increasing Mg concentration increased both growth and maximum cell density. The second experiment derived the Monod parameters ks (33 ± 7 mg/L) and umax (0.59 ± 0.04 days-1) for magnesium limited growth. The third experiment utilized ICP spectral analysis to monitor nutrient consumption over time allowing for the calculation of biomass yields for Mg (476 ± 132), Ca (247 ± 57.8), Fe (8550 ± 824), Mn (5310 ± 1450) all in g/

    Effects of Magnesium Sulfate, Digestate and Other Inorganic Nutrients on the Phototrophic Growth of the Green Microalga Scenedesmus Dimorphus

    Get PDF
    The individual components of the growth media, notably magnesium, have a profound impact on the growth and lipid production of the green microalgae, Scenedesmus dimorphus. The goal of this work was to investigate these effects and explain the causes via multiple experiments. It is important to understand the aspects of algal growth because they have a significant impact on the commercial viability of microalgal lipids as a potential feedstock for biofuel production. Digestate, derived from bovine waste and a potential cost effective nutrient replacement for conventional media types, was found to maximize growth and lipid concentration in S. dimorphus at 1.25 and 1.75 in water respectively and that increasing Mg concentration increased both growth and maximum cell density. The second experiment derived the Monod parameters ks (33 ± 7 mg/L) and umax (0.59 ± 0.04 days-1) for magnesium limited growth. The third experiment utilized ICP spectral analysis to monitor nutrient consumption over time allowing for the calculation of biomass yields for Mg (476 ± 132), Ca (247 ± 57.8), Fe (8550 ± 824), Mn (5310 ± 1450) all in g/
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