Abstract
In this paper we present the results from an experiment designed to characterize the Leap Motion movement in 2D pointing tasks and compare it to a mouse and touchpad. We used the ISO 9241-9 multi-directional tapping test for comparing the devices, and we analyse the results using standard throughput and error rate measures as well as additional accuracy measures such as target re-entry, task axis crossing, movement direction change, orthogonal direction change, movement variability, movement offset, and movement error. We also present the results from the ISO 9241-9 assessment of comfort questionnaire, and our observations from the participant's postures when using the Leap Motion device. Results indicate that the Leap Motion performs poorly in these tasks when compared to a mouse or touchpad.

Abstract
Oceans have shown tremendous importance and impact on our lives. Thus the need for monitoring and protecting the oceans has grown exponentially in recent years. On the other hand, oceans have economical and industrial potential in areas such as pharmaceutical, oil, minerals and biodiversity. This demand is increasing and the need for high data rate and near-real-time communications between submerged agents became of paramount importance. Among the needs for underwater communications, streaming video (e.g. for inspecting risers or hydrothermal vents) can be seen as the top challenge, which when solved will make all the other applications possible. Presently, the only reliable approach for underwater video streaming relies on wired connections or tethers (e.g. from ROVs to the surface) which presents severe operational constraints that makes acoustic links together with AUVs and sensor networks strongly appealing. Using new polymer-based acoustic transducers, which in very recent works have shown to have bandwidth and power efficiency much higher than the usual ceramics, this article proposes the development of a reprogrammable acoustic modem for operating in underwater communications with video streaming capabilities. The results have shown a maximum data-rate of 1Mbps with a simple modulation scheme such as OOK, at a distance of 20 m.

Abstract
Websites quality is strategically important for organizations and for their clients' satisfaction. The rapid growth of web applications increases the need to evaluate web applications quantitatively and qualitatively. When you attempt to evaluate websites, many different evaluation methods can be used. This paper analyzes and presents different quality models in order to perceive which is the most appropriate, depending on the situation.

Abstract

Abstract
Introduction: Pharyngocutaneous fistula after larynx and hypopharynx cancer surgery can cause serveral damages. This study's aim was to derive a clinical decision rule to predict pharyngocutaneous fistula development after pharyngolaryngeal cancer surgery. Methods: A retrospective cohort study was conducted, including all patients performing total laryngectomy/pharyngolaryngectomy (n = 171). Association between pertinent variables and pharyngocutaneous fistula development was assessed and a predictive model proposed. Results: American Society of Anesthesiologists scale, chemoradiotherapy, and tracheotomy before surgery were associated with fistula in the univariate analysis. In the multivariate analysis, only American Society of Anesthesiologists maintained statistical significance. Using logistic regression, a predictive model including the following was derived: American Society of Anesthesiologists, alcohol, N-classification, and diabetes mellitus. The model's score area under the curve was 0.76 (95% CI 0.64-0.87). The high-risk group presented specificity of 93%, positive likelihood ratio of 7.10, and positive predictive value of 76%. Including the medium-low, medium-high, and high-risk groups, a sensitivity of 92%, negative likelihood ratio of 0.25, and negative predictive value of 89% were observed. Conclusion: A clinical decision rule was created to identify patients with high risk of pharyngocutaneous fistula development. Prognostic accuracy measures were substantial. Nevertheless, it is essential to conduct larger prospective studies for validation and refinement.

Abstract
Humans sense the surrounding environment through five senses: sight, hearing, taste, smell and touch. This is valid not only for real life but also when one is exposed to virtual environments. It already exists systems that exploit the sensorial stimulation of more than one sense, however there are no available low-cost solutions that allow creative professionals to create and visualize multisensory contents. On this paper it is presented a solution for the creation and delivery of multisensory contents that allow users to create their own multisensory experiments. An evaluation of the developed solution that shows the potential of these new contents is also described.