Measuring dispositional optimism in patients with chronic heart failure and their healthcare providers : the validity of the Life Orientation Test-Revised

The Life Orientation Test-Revised (LOT-R) measures dispositional optimism (DO) - an individual difference promoting physical and psychological well-being in healthy adults (HAs) as well as in patients with chronic heart failure (CHF) and healthcare providers (HPs). Controversy has arisen regarding the dimensionality of the LOT-R. Whereas DO was originally defined as a one-dimensional construct, empirical evidence suggests two correlated factors in the LOT-R. This study was the first attempt to identify the best factor structure of the LOT-R in patients with CHF and HPs and to evaluate its measurement invariance among subsamples of patients with CHF, HPs, and a normative sample of HAs. Its validity was also evaluated in patients with CHF. The sample comprised 543 participants (34% HAs; 34% HPs; and 32% CHF patients). Congeneric, two correlated factor, and two orthogonal factor models for the LOT-R were compared by performing confirmatory factor analysis (CFA). Measurement invariance was evaluated by considering differential item functioning (DIF) among subsamples of HPs, patients with CHF, and HAs. In patients with CHF, validity was assessed by considering associations with anxiety and depression. The CFA demonstrated the superior fit of the two orthogonal factor model. Moreover, across patients with CHF, HPs, and HAs, the results highlighted a minimal DIF with only trivial consequences. Finally, negative but weak correlations of DO with anxiety and depression confirmed the validity of the LOT-R in patients with CHF. In summary, these findings supported the validity and suitability of the LOT-R for the assessment of DO in patients with CHF, HPs, and HAs

The Moby Dick architecture

This document is deliverable II.3.1, and presents the the MobyDick architecture. The introduction outlines the main areas of use and the main characteristics of the Pocket Companion, and ends up with the overall demands we put on the architecture. In chapter 2 Quality of Service (QoS) as we use it in MobyDick QoS is presented. It gives the foundation the adaptability used in the chapters to follow. In chapter 3 an overview of the software architecture of the Pocket Companion is presented. The security architecture of the Pocket Companion is presented in chapter 4, and the consistency architecture is presented in chapter 5. In chapter 6, the system\ud architecture of the Pocket Companion is outlined

A Cross-Layer Approach for Publish/Subscribe in Mobile Ad Hoc Networks

In the context of ubiquitous and pervasive computing, publish/subscribe middleware is gaining momentum due to its loosely coupled communication scheme. In this paper we present Q, a publish/subscribe service conceived to operate over mobile ad hoc networks. With Q, the overlay network that routes events from publishers to subscribers dynamically adapts to topology changes by means of cross-layer interaction. Q also supports content-based filtering of events through mobile code: subscribers can specify in detail the notifications they wish to receive by defining proper filter classes, then binary code of filters is exchanged during runtime by participating nodes

Continuous authentication through gait analysis on a wrist-worn device

Being distinctive of every individual, gait can be used as a biometric feature to authenticate the owner of a wearable device. This paper proposes and evaluates an authentication method that relies on the acceleration signal acquired at the user's wrist. During the training phase, the wrist-worn device automatically learns the gait patterns of the legitimate user, by exploiting a set of acceleration-based indicators. Subsequently, unauthorized users are detected by observing the occurrence of anomalous gait patterns. Experimental results carried out with 20 volunteers show that the proposed method is able to recognize the legitimate user with an equal error rate of ∼2.5%. The method is sufficiently lightweight to be executed in real time on a wearable device with limited resources. This enables continuous authentication without requiring the presence of an external device (e.g., a smartphone). Furthermore, the provided evaluation of power consumption shows that the completely on-node solution is also more energy efficient with respect to off-loading computation to an external device

Parallel implementation of the median filtering of images by using a network of transputers

The image processing capability of a multiple instruction stream, multiple data stream (MIMD) architecture, based on a network of transputers, has been evaluated for the case of the parallel implementation of a digital median filter. An effort has been made to give a clearly explained, practical use of transputers, which make parallel processing an affordable affair. The software and the hardware architectures are described along with basic results

Are we synchronised ? Measure synchrony in a team sport using a network of wireless accelerometers

Movements synchronism is a key parameter for team sports. To determine whether human movements in rowing are synchronous or not, we developed a system that acquires signals through accelerometers and compares those signals using correlation. System components are tuned to reduce the delay between the time at which the action occurs and the one the system produces the output. We present an application to help training synchronized movements and use it to test the system with elite rowing athletes. The system generates the output within 500 ms from the moment of the movement