The stability of a lentil lectin, an all-beta protein, has been perturbed by changes in pH and temperature. In the pH interval 5.0 --> 10.0, the overall secondary structure does not undergo significant changes. However, if the individual components of the infrared amide I band are considered, changes in band components attributed to variations in beta-sheet and beta-turns cross-interactions are detected. The combined effects of pH and temperature reveal that the protein is more compact at pH 7.5 with lower denaturation temperatures at pH 5.0 or 10.0, indicating a less stable protein under those conditions. According to our results, the structural stability of the beta-sheet would depend not only on the intermolecular interactions among the strands but also on the conformation of the segments connecting these strands. The protein infrared band assignment has also been examined since the three-dimensional structure of the lentil lectin protein is known from X-ray diffraction studies. Two of the bands observed are attributed to beta-sheet. The one at 1620 cm-1, not affected if the medium is deuterated, is assigned to hairpins composed by two strands connected by a rigid turn whereas that located at 1633 cm-1 corresponds to strands associated by more flexible segments. The band appearing at 1645 cm-1 in H2O corresponds to the open, flexible loops that are connecting the beta-strands. The simplest assumption of the various secondary structure components having identical IR extinction coefficients is enough to provide IR-derived data that are in good agreement with the structure solved by X-ray diffraction.

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Sensor web systems, cyber-physical systems, and the so-called Internet of Things are concepts that share a set of common characteristics. The nature of such systems is highly dynamic and very heterogeneous and issues such as interoperability, energy consumption, or resource management must be properly managed to ensure the operation of the applications within the required quality of service level. In this context, base technologies such as component based software engineering or Service Oriented Architecture can play a central role. Model driven development and middleware technologies also aid in the design, development, and operation of such systems. This paper presents a middleware solution that provides runtime support for the complete lifecycle management of a system consisting of several concurrent applications running over a set of distributed infrastructure nodes. The middleware builds up on top of a general purpose component model and is driven by a quality of service aware self-configuration algorithm that provides stateful reconfiguration capabilities in face of both internal (application triggered) and external (application unaware) reconfiguration events. The platform has been deployed over an automated warehouse supervision system that serves as a case study.

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In developed countries, public health systems are under pressure due to the increasing percentage of population over 65. In this context, homecare based on ambient intelligence technology seems to be a suitable solution to allow elderly people to continue to enjoy the comforts of home and help optimize medical resources. Thus, current technological developments make it possible to build complex homecare applications that demand, among others, flexibility mechanisms for being able to evolve as context does (adaptability), as well as avoiding service disruptions in the case of node failure (availability). The solution proposed in this paper copes with these flexibility requirements through the whole life-cycle of the target applications: from design phase to runtime. The proposed domain modeling approach allows medical staff to design customized applications, taking into account the adaptability needs. It also guides software developers during system implementation. The application execution is managed by a multi-agent based middleware, making it possible to meet adaptation requirements, assuring at the same time the availability of the system even for stateful applications.

ABSTRACT:The interaction with real plants is a key issue in control engineering education in order to consolidate the concepts learned in the classroom. Unfortunately, for several reasons, real laboratories are not always available. On the other hand, Internet technologies have proved to be mature and reliable, becoming a common alternative in the creation of remote laboratories. However, the use of these technologies in complex remote laboratories is not a trivial task as several requisites must be satisfied simultaneously. This article proposes a methodology that eases the creation of remote laboratories establishing the steps to build up a remote access system. This methodology proposes a set of key components that can be used to define the access to a remote plant from a functional point of view. Some of these components are generic being reusable in most applications whereas others are application specific. In summary, the methodology allows designers to concentrate more on the functionality of the applications than on the technical aspects of the underlying technology. The use of this methodology is illustrated with a relatively complex example: A laboratory manufacturing cell. ß