920 research outputs found

    Reference apparatus for medical ultrasonic transducer

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    Once reference apparatus has been located properly, and its position on chest of patient has been recorded on skin by means of indelible fiducial marks, it is simple matter at later time to reposition probe on chest over heart. In this way, signals from exact same area of heart can be re-examined

    A Lie algebra attached to a projective variety

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    Each choice of a K\"ahler class on a compact complex manifold defines an action of the Lie algebra \slt on its total complex cohomology. If a nonempty set of such K\"ahler classes is given, then we prove that the corresponding \slt-copies generate a semisimple Lie algebra. We investigate the formal properties of the resulting representation and we work things out explicitly in the case of complex tori, hyperk\"ahler manifolds and flag varieties. We pay special attention to the cases where this leads to a Jordan algebra structure or a graded Frobenius algebra.Comment: AMSTeX v2.1, 46 page

    Higher Muscle Tissue Oxygenation When Exposed to Hypobaric Hypoxia Than Normobaric Hypoxia

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    There has been recent debate on the potential difference in physiological response between exposure to simulated altitude (normobaric hypoxia) and terrestrial altitude (hypobaric hypoxia). Purpose: To determine the difference in the physiological response to normobaric and hypobaric hypoxia during exercise. Methods: Eight recreationally active subjects (27 ± 5 y old, 73.1 ± 7.4 kg body weight, 170.6 ± 6.7 cm height, and 19.3 ± 9.2 % body fat) completed incremental cycling exercise to volitional fatigue in three separate environments: normobaric normoxia (NN; 350 m), normobaric hypoxia (NH; simulated 3094 m), and hypobaric hypoxia (HH; 3094 m). Heart rate, blood oxygen saturation, and muscle tissue oxygenation were measured at rest and continuously throughout the exercise trials. Results: Blood oxygen saturation (SpO2) was ~10% higher in NN compared to the two hypoxic conditions (p \u3c 0.001) at rest and all exercise stages, with no difference between NH and HH (p \u3e 0.05). Heart rate was higher at rest in HH (98 ± 13 bpm) compared to NN (83 ± 15 bpm, p = 0.011) and NH (84 ± 14 bpm, p = 0.001) which persisted until 165 watts at which point no difference was observed (p \u3e 0.05). Muscle tissue oxygenation was 17% higher in HH compared to NN and 19% higher than NH throughout exposure (p \u3c 0.05). Conclusion: This data indicates that the hypoxic stress resulting from normobaric and hypobaric hypoxia are not the sameand that hypobaric hypoxia may not result in hypoxia at the level of the tissue

    Exercise-Induced Interleukin-6 and Metabolic Responses in Hot, Temperate, and Cold Conditions

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    The purpose of this study was to determine the effects of exercise in hot, cold, and temperate environments on plasma interleukin-6 (IL-6). Eleven recreationally trained males (age = 25 ± 4 years, height = 178 ± 5 cm, weight = 79.4 ± 13.5 kg, body fat = 14.7 ± 3.6%, VO2 peak = 54.6 ± 11.5 ml kg-1 min-1) performed a 1 hr cycling bout in hot (33 °C), cold (7 °C), and temperate (20 °C) environments at 60% of Wmax followed by 3 hr of supine recovery in temperate conditions. Expired gases were measured every 15 min during exercise and once every hour during recovery. Heart rate was continuously measured throughout the trials. Blood samples were obtained from the antecubital vein pre-exercise, immediately post-exercise, and 3 hr post-exercise. Blood samples were analyzed for plasma concentrations of IL-6 using a commercial ELISA kit. Plasma IL-6 concentrations were significantly higher immediately post-exercise (14.8 ± 1.6 pg ml-1, p = 0.008) and 3 hr post-exercise (14.8 ± 0.9 pg ml-1, p = 0.018) compared to pre-exercise (11.4 ± 2.4 pg ml-1), across all trials. There were no differences in plasma IL-6 concentrations (p = 0.207) between temperature conditions.Oxygen consumption and heart rate were higher and respiratory exchange ratio was lower in the hot compared to other conditions (p \u3c 0.05). These data indicate that the temperature in which exercise occurs does not affect acute plasma IL-6 response despite differences in metabolic state

    Search for High Spin Particle-Hole States in 20-Ne

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    This research was sponsored by the National Science Foundation Grant NSF PHY 87-1440

    Unexpectedly long incubation period of Plasmodium vivax malaria, in the absence of chemoprophylaxis, in patients diagnosed outside the transmission area in Brazil

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    <p>Abstract</p> <p>Background</p> <p>In 2010, Brazil recorded 3343,599 cases of malaria, with 99.6% of them concentrated in the Amazon region. <it>Plasmodium vivax </it>accounts for 86% of the cases circulating in the country. The extra-Amazonian region, where transmission does not occur, recorded about 566 cases imported from the Amazonian area in Brazil and South America, from Central America, Asia and African countries. Prolonged incubation periods have been described for <it>P. vivax </it>malaria in temperate climates. The diversity in essential biological characteristics is traditionally considered as one possible explanation to the emergence of relapse in malaria and to the differences in the duration of the incubation period, which can also be explained by the use of chemoprophylaxis. Studying the reported cases of <it>P. vivax </it>malaria in Rio de Janeiro, where there is no vector transmission, has made it possible to evaluate the extension of the incubation period and to notice that it may be extended in some cases.</p> <p>Methods</p> <p>Descriptive study of every malaria patients who visited the clinic in the last five years. The mean, standard deviation, median, minimum and maximum of all incubation periods were analysed.</p> <p>Results</p> <p>From the total of 80 patients seen in the clinic during the study time, with confirmed diagnosis of malaria, 49 (63%) were infected with <it>P. vivax</it>. Between those, seven had an estimated incubation period varying from three to 12 months and were returned travellers from Brazilian Amazonian states (6) and Indonesia (1). None of them had taken malarial chemoprophylaxis.</p> <p>Conclusions</p> <p>The authors emphasize that considering malaria as a possible cause of febrile syndrome should be a post-travel routine, independent of the time elapsed after exposure in the transmission area, even in the absence of malaria chemoprophylaxis. They speculate that, since there is no current and detailed information about the biological cycle of human malaria plasmodia's in Brazil, it is possible that new strains are circulating in endemic regions or a change in cycle of preexisting strains is occurring. Considering that a prolonged incubation period may confer advantages on the survival of the parasite, difficulties in malaria control might arise.</p

    (d,n) Reaction Studies at 80 MeV

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    This research was sponsored by the National Science Foundation Grant NSF PHy 87-1440

    Limitations of Student Control: Do Students Know when They Need Help?

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