Nächtliche Bronchialobstruktionen und Schlaf - Ergebnisse von akustischer Langzeitregistrierung und Polysomnographie

Die Bedeutung eines erholsamen Schlafs für die Gesundheit ist gesichert. Leistungsfähigkeit und Erholungsfunktion des Schlafes sind an das synchron ablaufende Wechselspiel der Funktionen Wachen und Schlafen gekoppelt. Eine Störung des zirkadianen Rhythmus der Schlaf/Wachphase führt vor allem zu einer Einschränkung der psychomentalen Leistungsfähigkeit, was sich in Form von verstärkter Tagesmüdigkeit, Antriebsarmut, Konzentrationsmangel sowie Stimmungs-schwankungen zeigt. Patienten mit obstruktiver Atemwegserkrankung klagen häufig über respiratorische Beschwerden im Schlaf. Das Ziel der Arbeit war es daher, eine genauere Beurteilung der Wechselwirkungen zwischen bronchialen Obstruktionen und Schlafparametern zu ermöglichen. In der vorliegenden Studie wurden 20 Patienten (9 Männer und 11 Frauen) mit Asthma bronchiale / COPD sowie einer klinisch auskultatorisch objektivierbaren bronchialen Obstruktion während der Nacht mit einer kardiorespiratorischen Polysomnographie und einer gleichzeitigen akustischen Aufzeichnung der Lungengeräusche mit dem PulmoTrack© Model 1010 prospektiv untersucht. Das Alter der Patienten lag im Mittel bei 55,4±12,4 Jahren (Range 23 bis 74 Jahre). Die Schlafstruktur fand sich bei allen 20 Patienten gestört. Im Mittel ergaben sich reduzierte Werte für die Gesamtschlafzeit (312±110 Min.), die Schlafeffizienz (66±21%) und den REM-Schlaf (16±7%) bei gleichzeitig verlängerter Schlaflatenz (47±55 Min.). Bei vier Patienten wurde nebenbefundlich eine obstruktive Schlafapnoe (RDI>=10/h) neu diagnostiziert. Bei allen Patienten konnten akustisch nächtliche Bronchialobstruktionen erfasst werden. Die Wheezingdauer reichte von 30 Sekunden bis zu 317 Minuten. Die Wheezing-Erkennung durch das PulmoTrack© funktionierte gut und zuverlässig. Es konnte für die thorakal gemessenen Obstruktionen eine Tendenz gefunden werden, die auf einen Zusammenhang zwischen zunehmendem Wheezing und zunehmender Vigilanz hindeutet (p<0,1). Für die trachealen Aufzeichnungen waren keine signifikanten Ergebnisse zu finden. Die Häufigkeit des Auftretens zentraler Weckreaktionen bei Bronchialobstruktionen war tendenziell erhöht (p<0,1). Um die Frage der pathophysiologischen Verknüpfung von Bronchialobstruktionen und Schlafparametern genauer beantworten zu können, ist die Durchführung weiterer Studien mit größeren, einheitlich strukturierten Patientenkollektiven notwendig. Das Langzeitmonitoring der Atemgeräusche stellt ein sinnvolles und effizientes Verfahren zur Beurteilung von bronchialen Obstruktionen dar, das zukünftig auch zur Beurteilung der antiobstruktiven Therapieeffizienz bei Patienten mit Asthma bronchiale und COPD dienen kann

On the nature of amorphous polymorphism of water

We report elastic and inelastic neutron scattering experiments on different amorphous ice modifications. It is shown that an amorphous structure (HDA') indiscernible from the high-density phase (HDA), obtained by compression of crystalline ice, can be formed from the very high-density phase (vHDA) as an intermediate stage of the transition of vHDA into its low-density modification (LDA'). Both, HDA and HDA' exhibit comparable small angle scattering signals characterizing them as structures heterogeneous on a length scale of a few nano-meters. The homogeneous structures are the initial and final transition stages vHDA and LDA', respectively. Despite, their apparent structural identity on a local scale HDA and HDA' differ in their transition kinetics explored by in situ experiments. The activation energy of the vHDA-to-LDA' transition is at least 20 kJ/mol higher than the activation energy of the HDA-to-LDA transition

Reconfiguration of Reo Connectors Triggered by Dataflow

Reo is a language for coordinating autonomous components in distributed environments. Coordination in Reo is performed by circuit-like connectors, which are constructed from primitive, mobile channels with well-defined behaviour. While the structure of a connector can be modeled as a graph, its behaviour is compositionally defined using that of its primitive constituents. In previous work, we showed that graph transformation techniques are well-suited to model reconfigurations of connectors. In this paper, we investigate how the connector colouring semantics can be used to perform dynamic reconfigurations. Dynamic reconfigurations are triggered by dataflow in the connector at runtime, when certain structural patterns enriched with dataflow annotations occur. For instance we are able to elegantly model dynamic Reo circuits, such as just-in-time augmentation of single-buffered channels to a circuit that models a channel with an unbounded buffer. Additionally we extend Reo's visual notation and the Reo animation language to describe and animate dynamically reconfiguring connectors

Integrated Structure and Semantics for Reo Connectors and Petri Nets

In this paper, we present an integrated structural and behavioral model of Reo connectors and Petri nets, allowing a direct comparison of the two concurrency models. For this purpose, we introduce a notion of connectors which consist of a number of interconnected, user-defined primitives with fixed behavior. While the structure of connectors resembles hypergraphs, their semantics is given in terms of so-called port automata. We define both models in a categorical setting where composition operations can be elegantly defined and integrated. Specifically, we formalize structural gluings of connectors as pushouts, and joins of port automata as pullbacks. We then define a semantical functor from the connector to the port automata category which preserves this composition. We further show how to encode Reo connectors and Petri nets into this model and indicate applications to dynamic reconfigurations modeled using double pushout graph transformation

THz and far-infrared radiation from ionizing multi-color pulses

International audienceResearch on intense terahertz (THz) electromagnetic sources has received an increasing attention owing to numerous applications, for example, in time-domain spectroscopy, biomedical imaging or security screening. Here, THz emission in gases via ionizing multi-color femtosecond pulses is analyzed by means of semi-analytical models and finite-difference-time-domain simulations in 1D and 2D geometries. We find the emission in backward direction having a much smaller spectral bandwidth than in forward direction and explain this by interference effects. Forward THz radiation is generated predominantly at the ionization front and thus almost not affected by the opacity of the plasma, in excellent agreement with results obtained from a unidirectional pulse propagation model. Moreover, we show that produced THz signals interact with free electron trajectories andthus influence significantly further THz generation upon propagation, i.e., make the process inherently nonlocal. This self-action plays a key role in the observed strong spectral broadening of the generated THz field in forward direction. Diffraction limits the achievable THz bandwidth by efficiently depleting the low frequency amplitudes in the propagating field

Proteomic analysis of 14-3-3 zeta binding proteins in the mouse hippocampus.

14-3-3 proteins are ubiquitous molecular chaperones with important roles in brain development and neuronal function. Altered expression of 14-3-3 proteins has been reported in several neurologic and neurodegenerative disorders and identifying 14-3-3 binding proteins may provide important insights into the physiologic and pathophysiologic roles of these proteins. Particular interest has emerged on 14-3-3 zeta (ζ) in the setting of neuronal injury because reducing 14-3-3ζ levels triggers an endoplasmic reticulum stress-like response in neurons and increases vulnerability to excitotoxicity. Here we examined the subcellular distribution of 14-3-3ζ in the mouse hippocampus. We then used recombinant His-tagged 14-3-3ζ to pull-down interacting proteins from the mouse hippocampus followed by identification by liquid chromatography-mass spectrometry. 14-3-3ζ protein was present in the cytoplasm, microsomal compartment, nucleus and mitochondrial fractions of the mouse hippocampus. Recombinant 14-3-3ζ eluted 13 known 14-3-3 binding partners, including three other 14-3-3 isoforms, and 16 other proteins which have not previously been reported to bind 14-3-3ζ. The present study identifies potentially novel 14-3-3ζ binding proteins and contributes to defining the 14-3-3ζ interactome in the mouse brain

Stiffness Control of Deformable Robots Using Finite Element Modeling

International audienceDue to the complexity of modeling deformable materials and infinite degrees of freedom, the rich background of rigid robot control has not been transferred to soft robots. Thus, most model-based control techniques developed for soft robots and soft haptic interfaces are specific to the particular device. In this paper, we develop a general method for stiffness control of soft robots suitable for arbitrary robot geometry and many types of actuation. Extending previous work that uses finite element modeling for position control, we determine the relationship between end-effector and actuator compliance, including the inherent device compliance, and use this to determine the appropriate controlled actuator stiffness for a desired stiffness of the end-effector. Such stiffness control, as the first component of impedance control, can be used to compensate for the natural stiffness of the deformable device and to control the robot's interaction with the environment or a user. We validate the stiffness projection on a deformable robot and include this stiffness projection in a haptic control loop to render a virtual fixture