891 research outputs found

    Casimir Invariants for Systems Undergoing Collective Motion

    Full text link
    Dicke states are states of a collection of particles which have been under active investigation for several reasons. One reason is that the decay rates of these states can be quite different from a set of independently evolving particles. Another reason is that a particular class of these states are decoherence-free or noiseless with respect to a set of errors. These noiseless states, or more generally subsystems, can avoid certain types of errors in quantum information processing devices. Here we provide a method for calculating invariants of systems of particles undergoing collective motions. These invariants can be used to determine a complete set of commuting observables for a class of Dicke states as well as identify possible logical operations for decoherence-free/noiseless subsystems. Our method is quite general and provides results for cases where the constituent particles have more than two internal states.Comment: 5 page

    Method for Treating Ischemia

    Get PDF
    A method for treating ischemia by administering deltorphins to a mammal. Deltorphin I SEQ ID NO:1, delntorphin II SEQ ID NO:2 or combinations of deltorphins I SEQ ID NO:1 and II SEQ ID NO:2 may be administered. A deltorphin concentration of about 0.5-20 mg/kg body weight, or alternatively a lower concentration of about 1-1000 μg/kg body weight of the mammal in a physiologically acceptable formulation is administered up to four hours after an ischemic episode. Deltorphins may also be administered prior to or concurrently with onset of ischemia. Cerebral or spinal cord ischemia or ischemic heart disease may be treated using the method of the invention

    Protection Against Ischemia and Reperfusion Injury

    Get PDF
    A compound and method for using the compound to reduce injury associated with ischemia and reperfusion of mammalian organs such as the heart. The compound, either Deltorphin A and/or Dermorphin H, may be administered as part of a preconditioning strategy which reduces the extent of injury and improves organ function following cessation and restoration of blood flow. The compound may be used in preparation for planned ischemia or in a prophylactic manner in anticipation of further ischemic events

    Self-reported pain and disability outcomes from an endogenous model of muscular back pain

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Our purpose was to develop an induced musculoskeletal pain model of acute low back pain and examine the relationship among pain, disability and fear in this model.</p> <p>Methods</p> <p>Delayed onset muscle soreness was induced in 52 healthy volunteers (23 women, 17 men; average age 22.4 years; average BMI 24.3) using fatiguing trunk extension exercise. Measures of pain intensity, unpleasantness, and location, and disability, were tracked for one week after exercise.</p> <p>Results</p> <p>Pain intensity ranged from 0 to 68 with 57.5% of participants reporting peak pain at 24 hours and 32.5% reporting this at 48 hours. The majority of participants reported pain in the low back with 33% also reporting pain in the legs. The ratio of unpleasantness to intensity indicated that the sensation was considered more unpleasant than intense. Statistical differences were noted in levels of reported disability between participants with and without leg pain.</p> <p>Pain intensity at 24 hours was correlated with pain unpleasantness, pain area and disability. Also, fear of pain was associated with pain intensity and unpleasantness. Disability was predicted by sex, presence of leg pain, and pain intensity; however, the largest amount of variance was explained by pain intensity (27% of a total 40%). The second model, predicting pain intensity only included fear of pain and explained less than 10% of the variance in pain intensity.</p> <p>Conclusions</p> <p>Our results demonstrate a significant association between pain and disability in this model in young adults. However, the model is most applicable to patients with lower levels of pain and disability. Future work should include older adults to improve the external validity of this model.</p

    Protection Against Ischemia and Reperfusion Injury

    Get PDF
    A compound and method for using the compound to reduce injury associated with ischemia and reperfusion of mammalian organs such as the heart. The compound, either Deltorphin A and/or Dermorphin H, may be administered as part of a preconditioning strategy which reduces the extent of injury and improves organ function following cessation and restoration of blood flow. The compound may be used in preparation for planned ischemia or in a prophylactic manner in anticipation of further ischemic events

    Protection Against Ischemia and Reperfusion Injury

    Get PDF
    A compound and method for using compound-D SEQ ID NO:1 to reduce injury associated with ischemia and reperfusion of mammalian organs such as the heart. The compound may be administered as part of a preconditioning strategy which reduces the extent of injury and improves organ function following cessation and restoration of blood flow. The compound may be used in preparation for planned ischemia or in a prophylactic manner in anticipation of further ischemic events

    Protection Against Ischemia and Reperfusion Injury

    Get PDF
    A compound and method for using the compound to reduce injury associated with ischemia and reperfusion of mammalian organs such as the heart. The compound may be administered as part of a preconditioning strategy which reduces the extent of injury and improves organ function following cessation and restoration of blood flow. The compound may be used in preparation for planned ischemia or in a prophylactic manner in anticipation of further ischemic events

    Stability of behavioral estimates of activity-dependent modulation of pain

    Get PDF
    Temporal sensory summation of pain (TSSP) is a proxy measure of windup in humans and results in increased ratings of pain caused by a repetitive, low-frequency noxious stimulus. Aftersensations (ASs) are pain sensations that remain after TSSP has been induced. We examined the within-session and across-session variability in TSSP and AS estimation in healthy participants and in participants with exercise-induced muscle pain in order to determine whether the presence of pain affected the stability of TSSP and ASs. TSSP was estimated by application of 10 repetitive, low-frequency (<0.33 Hz) thermal pulses and measured by the simple slope of pain ratings between the first and fifth pulses. ASs were measured by the presence of any remaining pain sensations up to 1 minute after TSSP was induced. TSSP estimation remained moderately stable in pain-free participants and in participants with pain within a single testing session but demonstrated low stability across sessions in pain-free participants. AS estimation was stable for all groups. Estimation of TSSP and ASs using these protocols appears to be a reliable single-session outcome measure in studies of interventions for acute muscle pain and in experimental studies with healthy participants. This article evaluates the reliability of a commonly used method of estimating TSSP and ASs in both healthy participants and in a clinically relevant model of acute pain. These protocols have the potential to be used as single-session outcome measures for interventional studies and in experimental studies
    • …
    corecore