The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
Jonathan R. Partington - One of the best experts on this subject based on the ideXlab platform.
-
Lethargy results in lti system modelling
Automatica, 1998Co-Authors: Pertti M. Mäkilä, Jonathan R. PartingtonAbstract:Modelling of linear time-invariant (LTI) systems is studied in an approximate modelling framework motivated by modern robust control theory. As convolution-type LTI systems are represented by their unit impulse responses (i.e. through a sequence of real (complex) numbers), this paper provides also system theoretic results on modelling of sequences and their associated transfer functions. The modelling results derived in this paper are mostly of Lethargy type, i.e. they establish limitations in approximate modelling of LTI systems. Non-existence of coprime factorizations is established for a number of different types of LTI systems. This leads to the somewhat surprising conclusion that many LTI systems are not even stabilizable and that an even larger class of LTI systems cannot be well-approximated by rational transfer function models. In addition, it is discussed that often the rate of rational approximation of LTI systems is not essentially better than the rate of approximation in some basis (such as finite impulse response (FIR) models). Furthermore, different definitions of the important finite power signal setup are studied and new results given.
-
Lethargy Results in LTI System Modelling
IFAC Proceedings Volumes, 1997Co-Authors: Pertti M. Mäkilä, Jonathan R. PartingtonAbstract:Abstract Modelling of linear time-invariant (LTI) systems is studied in an approximate modelling framework motivated by modern robust control theory. The modelling results derived in this paper are mostly of Lethargy type, i.e. they establish limitations in approximate modelling of LTI systems. Non-existence of coprime factorizations is established for a number of different types of LTI systems. This leads to the somewhat surprising conclusion that many LTI systems are not even stabilizable and that an even larger class of LTI systems can not be well-approximated by rational transfer function models. Furthermore, different definitions of the important finite power signal setup are studied and new results given.
Daniel A Mordes - One of the best experts on this subject based on the ideXlab platform.
-
case records of the massachusetts general hospital case 12 2015 a newborn boy with respiratory distress Lethargy and hypernatremia
The New England Journal of Medicine, 2015Co-Authors: Tingyi Lin, David H Ebb, Paul A Boepple, Elizabeth A Thiele, Sandra Rincon, Daniel A MordesAbstract:A newborn boy was admitted to the hospital because of respiratory distress and hypotension. At delivery, meconium was suctioned from the airway. Respiration and blood pressure improved after intervention, but Lethargy and myoclonus developed.
Lois M. Harden - One of the best experts on this subject based on the ideXlab platform.
-
differences in the relative involvement of peripherally released interleukin il 6 brain il 1β and prostanoids in mediating lipopolysaccharide induced fever and sickness behavior
Psychoneuroendocrinology, 2011Co-Authors: Lois M. Harden, Irne Du Plessis, Joachim Roth, Lisa C Loram, Stephen Poole, Helen P LaburnAbstract:Summary Although peripherally released interleukin (IL)-6 is critical for fever, its role in sickness behaviors, in particular anorexia and Lethargy, induced by lipopolysaccharide (LPS) administration appears to be less important. Using quantifiable measures of fever, anorexia and Lethargy, that is, body temperature, food intake and voluntary wheel-running, we investigated whether the less-than-essential role for IL-6 in mediating sickness behaviors compared to fever implies important roles for other inflammatory mediators, particularly IL-1β and prostanoids, in these responses. Male Sprague–Dawley rats were randomly assigned to receive one of the following three injections before receiving a subcutaneous (SC) injection of LPS (250 μg/kg) or saline: (1) intraperitoneal injection of pre-immune serum or antiserum to IL-6 (IL-6AS), to reduce the biological activity of peripherally released IL-6; (2) intracerebroventricular injection of vehicle or a caspase-1 inhibitor, to inhibit the production of mature IL-1β; or (3) intraperitoneal injection of vehicle or one of the two doses (1 or 10 mg/kg) of diclofenac, a nonselective cyclooxygenase inhibitor shown to block the formation of prostanoids. LPS administration induced fever, anorexia and Lethargy with an accompanying increase in IL-6 and IL-1β concentrations in the circulation and IL-1β in the brain. Rats pre-treated with: (1) IL-6AS had reduced plasma levels of bioactive IL-6, no fever and attenuated sickness behaviors; (2) the caspase-1 inhibitor had reduced concentrations of IL-1β in the pre-frontal cortex, hypothalamus and hippocampus, and attenuated fever and sickness behaviors; (3) diclofenac had a dose-dependent attenuation in fever and sickness behaviors. Doses of diclofenac which completely abolished fever however had lesser effects on anorexia and Lethargy. Our results confirm a difference in the sensitivity of sickness responses to IL-6 antagonism and identify that it may be related to different levels of sensitivity or responsiveness in brain regions and/or mechanisms, to prostanoids, IL-1β, or IL-6 itself.
-
comparison of anorexia Lethargy and fever induced by bacterial and viral mimetics in rats
Canadian Journal of Physiology and Pharmacology, 2009Co-Authors: Nicola Hopwoodn. Hopwood, Tlangelani Maswanganyit. Maswanganyi, Lois M. HardenAbstract:Although it has been established that some acute phase responses present differently depending on whether a virus or bacteria activates the innate immune system, it has not yet been established whether fever and sickness behaviors, such as anorexia and Lethargy, present differently. We therefore investigated the effects of administering lipopolysaccharide (LPS) and polyinosinic : polycytidylic acid (poly I:C) on body temperature, food intake, body mass, and activity (cage activity and wheel running). Male Sprague–Dawley rats were randomly assigned to receive an intraperitoneal injection of one of LPS (75 µg/kg or 250 µg/kg), poly I:C (3000 µg/kg or 4000 µg/kg), or saline. Administration of LPS or poly I:C induced fever, anorexia, and Lethargy. Although voluntary wheel running and cage activity were both significantly reduced after administration of LPS or poly I:C, they were not affected equally. Indeed voluntary wheel running was decreased on average by approximately 30% more than cage activity regardles...
-
Comparison of anorexia, Lethargy, and fever induced by bacterial and viral mimetics in rats.
Canadian journal of physiology and pharmacology, 2009Co-Authors: Nicola Hopwoodn. Hopwood, Tlangelani Maswanganyit. Maswanganyi, Lois M. HardenAbstract:Although it has been established that some acute phase responses present differently depending on whether a virus or bacteria activates the innate immune system, it has not yet been established whether fever and sickness behaviors, such as anorexia and Lethargy, present differently. We therefore investigated the effects of administering lipopolysaccharide (LPS) and polyinosinic : polycytidylic acid (poly I:C) on body temperature, food intake, body mass, and activity (cage activity and wheel running). Male Sprague-Dawley rats were randomly assigned to receive an intraperitoneal injection of one of LPS (75 microg/kg or 250 microg/kg), poly I:C (3000 microg/kg or 4000 microg/kg), or saline. Administration of LPS or poly I:C induced fever, anorexia, and Lethargy. Although voluntary wheel running and cage activity were both significantly reduced after administration of LPS or poly I:C, they were not affected equally. Indeed voluntary wheel running was decreased on average by approximately 30% more than cage activity regardless of the dose or type of mimetic administered. Our results indicate that poly I:C is less effective at inducing anorexia, Lethargy, and fever in rats than is LPS, and that avoidance of exercise in animals and humans during infection is likely to be a more prominent feature of illness than is avoidance of routine daily activity.
Pertti M. Mäkilä - One of the best experts on this subject based on the ideXlab platform.
-
Lethargy results in lti system modelling
Automatica, 1998Co-Authors: Pertti M. Mäkilä, Jonathan R. PartingtonAbstract:Modelling of linear time-invariant (LTI) systems is studied in an approximate modelling framework motivated by modern robust control theory. As convolution-type LTI systems are represented by their unit impulse responses (i.e. through a sequence of real (complex) numbers), this paper provides also system theoretic results on modelling of sequences and their associated transfer functions. The modelling results derived in this paper are mostly of Lethargy type, i.e. they establish limitations in approximate modelling of LTI systems. Non-existence of coprime factorizations is established for a number of different types of LTI systems. This leads to the somewhat surprising conclusion that many LTI systems are not even stabilizable and that an even larger class of LTI systems cannot be well-approximated by rational transfer function models. In addition, it is discussed that often the rate of rational approximation of LTI systems is not essentially better than the rate of approximation in some basis (such as finite impulse response (FIR) models). Furthermore, different definitions of the important finite power signal setup are studied and new results given.
-
Lethargy Results in LTI System Modelling
IFAC Proceedings Volumes, 1997Co-Authors: Pertti M. Mäkilä, Jonathan R. PartingtonAbstract:Abstract Modelling of linear time-invariant (LTI) systems is studied in an approximate modelling framework motivated by modern robust control theory. The modelling results derived in this paper are mostly of Lethargy type, i.e. they establish limitations in approximate modelling of LTI systems. Non-existence of coprime factorizations is established for a number of different types of LTI systems. This leads to the somewhat surprising conclusion that many LTI systems are not even stabilizable and that an even larger class of LTI systems can not be well-approximated by rational transfer function models. Furthermore, different definitions of the important finite power signal setup are studied and new results given.
Tingyi Lin - One of the best experts on this subject based on the ideXlab platform.
-
case records of the massachusetts general hospital case 12 2015 a newborn boy with respiratory distress Lethargy and hypernatremia
The New England Journal of Medicine, 2015Co-Authors: Tingyi Lin, David H Ebb, Paul A Boepple, Elizabeth A Thiele, Sandra Rincon, Daniel A MordesAbstract:A newborn boy was admitted to the hospital because of respiratory distress and hypotension. At delivery, meconium was suctioned from the airway. Respiration and blood pressure improved after intervention, but Lethargy and myoclonus developed.
