Gastrointestinal stromal tumors (GISTs) are characterized by overexpression and mutations of c-Kit. Approximately 80% of c-Kit mutations occur in exon 11, being a response factor to imatinib (Gleevec) therapy. Mutations of platelet-derived growth factor receptor-α (PDGFRA) are observed in a subset of GISTs lacking c-Kit mutations.We aimed to assess whether c-Kit and PDGFRA mutation analysis of GISTs obtained by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) could be routinely performed. Mutation analysis of c-Kit hotspot exons (9, 11, 13, and 17) and PDGFRA hotspot exons (12 and 18) was performed in aspirates of 33 GISTs and 18 non-GIST mesenchymal tumors.Of the GIST cases, 19 (58%) of 33 contained a mutation in exon 11, 1 (3%) in exon 9, and none in exons 13 and 17. No activating c-Kit mutations were identified in non-GIST cases. No PDGFRA mutation was detected.Mutation analysis is possible in these FNA cell blocks and can assist in the diagnosis and therapeutic decisions in GIST cases.

Hands-free interaction with technology is a dream for any person with limitations in the use of his/her arms and hands. This paper describes two new original low-cost hands-free computer peripheries-I4Control Ò and Magic Key, which use movements of the user's eye or nose as an actuator of a computer cursor. Both systems emulate the PC mouse and thereby mediate direct access to any mouse-controlled computer application. Functionality of the presented systems is compared to that of PC mouse using one of the usability tests recommended by the ISO 9241 methodology. The data obtained as a result of testing a group of ten unimpaired novice users indicated that the users' performance improves over time of usage of the system, but the process is rather slow. The paper describes several easy to use toy-applications intended to improve the user's confidence in working with the considered devices. One of these applications demonstrates that I4Control Ò can be employed to control home appliances or a wheelchair.

Numerical models are essential tools for the study and analysis of the hydrodynamics of estuarine systems. However, the model results contain uncertainties, which need to be minimized to increase the accuracy of predictions. In this work, the ensemble technique is proposed as a solution to improve hydrodynamic forecasts for estuarine regions. Two numerical models, openTELEMAC-MASCARET and Delft3D, were considered for the application of this technique to two Portuguese estuaries. Superensembles for three scenarios (summer, winter, and extreme event) were built to assess the effectiveness of the technique in improving water level prediction. Various weighing techniques were tested in the construction of the ensembles. Weighing techniques that consider the previous performance of each model alone outperformed other techniques. This was observed for all scenarios considered, at all sampling points and in both studied estuaries. The effect of the ensemble size was also analyzed. It was found that the size of the set is directly related to the prediction accuracy, with the best results provided by the superensembles with the highest number of elements. It is concluded that the combined use of several hydrodynamic models reduces the uncertainty of the results and increases the reliability and consistency of predictions for estuarine regions.

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Coastal defence works, such as breakwaters, are structures that aim to support the action of waves and dissipate their energy. Therefore, they provide conditions for stabilizing the coast, protecting ports, beaches and other coastal infrastructures and ecosystems. Semicircular breakwaters have been applied in different locations around the world due to their aesthetic advantages and high structural performance. Marine structures are subject to hydrodynamic actions normally estimated through physical models. However, these models are complex to implement, involving high costs and long experimental procedures. Thus, alternative methodologies for studying the hydrodynamic performance of these structures are of great use. This work presents the results of the application of a computational fluid dynamics (CFD) tool to study the stability of a perforated semicircular breakwater, based on a rubble mound foundation. The model was validated against experimental results of the critical weight necessary to resist sliding, taking into account the effects of water depth and different characteristics of the waves. A comparison is made between the perforated and the non-perforated solution in terms of the breakwater’s performance to dissipate wave energy. Dissipation conditions of this energy, in the exposed face, are also evaluated in detail, in order to assess the potential of this structure as a biological refuge for marine species. Both solutions show similar performance in terms of results obtained for the wave reflectivity coefficient. The turbulence dissipation on the exposed face of the perforated breakwater is limited to a region of restricted extension around it, which is advantageous in terms of the passage of species into the breakwater.