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The term bronchial hyperresponsiveness is generally used to describe a heightened airway smooth muscle bronchoconstrictor response measured by bronchoprovocation testing. However, the airway also responds to inflammation or bronchoprovocation with increased mucus secretion. We use the term “secretory hyperresponsiveness” to mean increased mucus secretion either intrinsically or in response to bronchoprovocation. This is not the same as retained phlegm or sputum. Unlike smooth muscle contraction, which is rapidly reversible using a bronchodilator, mucus hypersecretion produces airflow limitation that reverses more slowly and depends upon secretion clearance from the airway. Certain groups of patients appear to have greater mucus secretory response, including those with middle lobe syndrome, cough-dominant (“cough-variant”) asthma, and severe asthma. Secretory hyperresponsiveness also is a component of forms of lung cancer associated with bronchorrhea. An extreme form of secretory hyperresponsiveness may lead to plastic bronchitis, a disease characterized by rigid branching mucus casts that obstruct the airway. Secretory hyperresponsiveness and mucus hypersecretion appear to be related to activation of the extracellular-regulated kinase 1/2, signaling through the epidermal growth factor receptor, or secretory phospholipases A2. Recognizing secretory hyperresponsiveness as a distinct clinical entity may lead to more effective and targeted therapy for these diseases.

This contribution considers an actuator based on Electroactive Polymers (EAPs) which is used for constructional elements with controllable stiffness. The actuator consists of a Danfoss PolyPower EAP-foil and a supporting structure which applies the necessary pre-straining force to the foil. Usually, such structures have a constant spring stiffness which strongly limits the actuation range. The novel actuator shows a highly nonlinear spring stiffness for pre-straining the foil. Therefore, the pre-straining force is nearly constant all over the entire actuation range. This behavior can be used to double the possible actuation range. Such structures are suitable to be used in construction elements with variable stiffness. The contribution shows the basic function of this actuator and its capabilities for the application in new smart, self-sensing and self-controlling composite materials for lightweight constructions. The theoretical background of highly nonlinear spring stiffness is discussed and transferred to the developed structures. The theoretical calculations are based on analytic calculations and finite element analyses and are verified by experimental set-ups consisting of different actuators both with constant and highly nonlinear pre-straining spring constant.

The contribution describes a new kind of multi-layer beam with a variable stiffness based on electroactive polymers (EAP). These structures are supposed to be components of new smart, self-sensing and -controlling composite materials for lightweight constructions. Dielectric Elastomer foils from Danfoss PolyPower are used to control the beam's stiffness. The basic idea is to change the area moment of inertia of bending beams. These beams are built up as multi-layer stacks of thin metal or PMMA plates. Its internal structure can be changed by the use of the electroactive polymers for controlling the area moment of inertia. So it is possible to strongly change the stiffness of bending beams up to two orders of magnitude. Thereby, the magnitude of varying the stiffness can be scaled by the number of layers and the number and type of electroactive polymer elements used within the bending beam. The mechanisms for controlling the area moment of inertia are described in detail. Modeling of the mechanical structure including the EAP uses a pseudo rigid-body model, a strain energy model as well as a finite element analysis. The theoretical calculations are verified by experiments. The prototype described here consists of two structural layers. First results show the feasibility of the proposed structure for mechanical components with stiffness control.

ABSTRACTAirway mucins are the major molecular constituents of mucus. Mucus forms the first barrier to invading organisms in the airways and is an important defense mechanism of the lung. We confirm that mucin concentrations are significantly decreased in airway secretions of subjects with cystic fibrosis (CF) who have chronic Pseudomonas aeruginosainfection. In sputum from CF subjects without a history of P. aeruginosa, we found no significant difference in the mucin concentration compared to mucus from normal controls. We demonstrate that mucins can be degraded by synthetic human neutrophil elastase (HNE) and P. aeruginosaelastase B (pseudolysin) and that degradation was inhibited by serine proteases inhibitors (diisopropyl fluorophosphates [DFP], phenylmethylsulfonyl fluoride [PMSF], and 1-chloro-3-tosylamido-7-amino-2-heptanone HCl [TLCK]). The mucin concentration in airway secretions from CF subjects is similar to that for normal subjects until there is infection by P. aeruginosa, and after that, the mucin concentration decreases dramatically. This is most likely due to degradation by serine proteases. The loss of this mucin barrier may contribute to chronic airway infection in the CF airway.

Airway mucins are the major molecular constituents of mucus. Mucus forms the first barrier to invading organisms in the airways and is an important defense mechanism of the lung. We confirm that mucin concentrations are significantly decreased in airway secretions of subjects with cystic fibrosis (CF) who have chronic Pseudomonas aeruginosa infection. In sputum from CF subjects without a history of P. aeruginosa, we found no significant difference in the mucin concentration compared to mucus from normal controls. We demonstrate that mucins can be degraded by synthetic human neutrophil elastase (HNE) and P. aeruginosa elastase B (pseudolysin) and that degradation was inhibited by serine proteases inhibitors (diisopropyl fluorophosphates [DFP], phenylmethylsulfonyl fluoride [PMSF], and 1-chloro-3-tosylamido-7-amino-2-heptanone HCl [TLCK]). The mucin concentration in airway secretions from CF subjects is similar to that for normal subjects until there is infection by P. aeruginosa, and after that, the mucin concentration decreases dramatically. This is most likely due to degradation by serine proteases. The loss of this mucin barrier may contribute to chronic airway infection in the CF airway.

This contribution considers an actuator based on Electroactive Polymers (EAPs) which is used for constructional elements with controllable stiffness. The actuator consists of a Danfoss PolyPower EAP-foil and a supporting structure which applies the necessary pre-straining force to the foil. Usually, such structures have a constant spring stiffness which strongly limits the actuation range. The novel actuator shows a highly nonlinear spring stiffness for pre-straining the foil. Therefore, the pre-straining force is nearly constant all over the entire actuation range. This behavior can be used to double the possible actuation range. Such structures are suitable to be used in construction elements with variable stiffness. The contribution shows the basic function of this actuator and its capabilities for the application in new smart, self-sensing and self-controlling composite materials for lightweight constructions. The theoretical background of highly nonlinear spring stiffness is discussed and transferred to the developed structures. The theoretical calculations are based on analytic calculations and finite element analyses and are verified by experimental set-ups consisting of different actuators both with constant and highly nonlinear pre-straining spring constant.

ABSTRACTBeauveriaspp. are ubiquitous fungal entomopathogens that are commercially distributed as biological insecticides worldwide. In this paper we describe the clinical manifestation, diagnosis, and therapy of the first documented human deep tissue infection with an entomopathogenic Beauveriaspecies in a patient receiving immunosuppressive therapy and describe the morphological and molecular characterization of the mold.

This contribution presents a linear drive module as mechatronic actuator for a new railway carriage. Here, according to the mechatronic methods, a double-fed longstator- linearmotor will be chosen and the control structure will be designed by means of modelling. The next steps in mechatronic design procedures are simulation and experimental validation. The presented motor propells a mechatronic railway carriage, which is also fitted with active suspension/tilting and steering modules.

This paper presents the design of a railway carriage whose drive is realized by a linear motor. An integrated suspension/tilt module makes possible increased ride comfort and cornering speed in comparison to existing systems.