Abstract
This work further clarifies how the MULTIS architecture can be used for integration of virtual worlds in learning management system (LMS) for organizational management of e-learning activities, as an extension to a previous work published in the proceedings of VEAI 2016. Current LMSs provide minimal support for educational use in an organizational context, and other integration efforts assume that educators are inside the virtual world, accessing the LMS as an external service. Our approach enables educators to set up and manage virtual world activities from within the traditional LMS Web interface as an integral part of the overall educational activities of a course. The MULTIS architecture foresees several alternative communication channels between LMS and virtual worlds, including the spooling of automated clients or "bots" and the flexibility to inject code if necessary and possible. In this work, we detail the application of this architecture and its approach in several sample scenarios, based on previous analysis of integration requirements. It is the result of a joint effort by academic and corporate teams, implemented and tested in the Formare LMS for OpenSimulator and Second Life Grid virtual world platforms.

Abstract
Robotic technologies are continuously transforming the domestic and the industrial environments. Recently the Robotic Operating System (ROS), has been widely adopted both by industry and academia, becoming one of the most popular middleware frameworks for developing robot applications. Guaranteeing the correct behaviour of robotic systems is, however, challenging due to their potential for parameterization and heterogeneity. Although different approaches exist, focusing on concrete domain spaces for specific scenarios, no general approach to reason about ROS systems has yet arisen. This paper proposes an approach to model and verify ROS systems using real time properties, focusing on one of the main features of ROS, the communication between nodes. It takes low-level parameters into account, such as queue sizes and timeouts, and uses timed automata as the modelling language. The robot Kobuki is used as a complex case study, over which properties are automatically verified using the UPPAAL model checker, enabling the identification of problematic parameter combinations.

Abstract
The development of economical optical devices with a reduced footprint foreseeing manipulation, sorting and detection of single cells and other micro particles have been encouraged by cellular biology requirements. Nonetheless, researchers are still ambitious for advances in this field. This paper presents Fresnel zone and phase plates fabricated on mode expanded optical fibres for optical trapping. The diffractive structures were fabricated using focused ion beam milling. The zone plates presented in this work have focal distance of similar to 5 mu m, while the focal distance of the phase plates is similar to 10 mu m. The phase plates are implemented in an optical trapping configuration, and 2D manipulation and detection of 8 mu m PMMA beads and yeast cells is reported. This enables new applications for optical trapping setups based on diffractive optical elements on optical fibre tips, where feedback systems can be integrated to automatically detect, manipulate and sort cells.

Abstract
In this paper we discuss the development of a fast ray-tracing solver for complex anisotropic uniaxial optical media based on heterogeneous supercomputing in GPGPU using PyOpenCl. This solver simulates both the propagation of ordinary and extraordinary rays, while taking into account the polarization rotation introduced by position dependent modulations of the optical axis of the medium. We demonstrate the application of this solver by simulating the generation of polarization caustics in random uniaxial optical media.

Abstract
Measuring the return on communication investments on social media has become one of the top key issues for organizations joining social networks. However, this field has been lacking articulation between what is conveyed as social media key performance indicators and the alignment of strategic organizational goals. Therefore, we propose a methodology to measure the performance of each organization on social media, to determine their positioning in the sector and to evaluate which are the content strategies used to boost the highest performing organizations. Thus, we identify how to determine which organizations should be closely monitored within the sector and which type content strategies can foster higher organizational performance on social media. © 2017 Copyright is held by the owner/author(s).

Abstract
Microfiber knot resonators find application in many different fields of action, of which an important one is the optical sensing. The large evanescent field of light can interact and sense the external medium, tuning the resonance conditions of the structure. The resonant property of microfiber knot resonators can also provide, in some cases, an enhancement in the sensing capability. Until nowadays, a wide variety of physical and chemical parameters have been possible to measure with this device. New developments and improvements are still being done in this field. A review on microfiber knot resonators as sensors is presented, with particular emphasis on their application as temperature and refractive index sensors. The properties of these structures are analyzed and different assembling configurations are presented. Important aspects in terms of the sensor stability are discussed, as well as alternatives to increase the sensor robustness. In terms of new advances, an overview on coated microfiber knot resonators is also presented. Finally, other microfiber knot configurations are explored and discussed.