A computational method for the steady 2-D flow in axially symmetrical rocket nozzles with a given profile is developed, in order to determine the Maximum thrust contour of rocket engine nozzles with large expansion ratio. The optimized nozzles proved a more than 10% increase in the integral specific impulse recorded during the variable altitude atmospheric flight of rocket vehicles. The method is well suited for application in the design of the optimum contour for axially-symmetric nozzles for atmospheric rocket ascent, specifically for aerospike type nozzles, as for other similar industrial applications in gas and steam turbine technology.

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The sphenoidal tubercle (SphT), also known as pyramidal tubercle or infratemporal spine projects from the anterior end of the infratemporal crest of the greater sphenoidal wing. As it masquerades the lateral entrance in the pterygopalatine fossa it could obstruct surgical corridors or the access for anaesthetic punctures. The SphT is, however, an overlooked structure in the anatomical literature. During a routine cone beam computed tomography study in an adult male patient we found bilateral giant SphTs transforming the infratemporal surfaces of the greater wing into veritable pterygoid foveae. Moreover, on one side the SphT appeared bifid, with a main giant partition, of 9.17 mm vertical length, and a secondary laminar one. The opposite SphT had 14.80 mm. In our knowledge, such giant and bifid SphTs were not reported previously and are major obstacles if surgical access towards the pterygopalatine fossa and the skull base is intended. (Folia Morphol 2019; 78, 4: 893-897) Key words: greater wing of the sphenoid bone, pterygopalatine fossa, cone beam computed tomography, infratemporal fossa, maxillary nerve

Most usability evaluation methods are designed to be applied after the implementation of a software product. As such, there is limited research on how to conduct usability evaluation procedures before the implementation of a software product, especially on cybersecurity platforms user interfaces. For this purpose, we illustrate the early usability evaluation of a cybersecurity graphical interface. In this sense, we conduct a usability evaluation procedure on the mockup of Yggdrasill, an application centered on the early identification of vulnerabilities using open-source intelligence, more specifically Tweeter posts and news websites. To achieve this, we conducted a usability inquiry procedure using the adaptation of a questionnaire designed to evaluate the attractiveness of interactive products. In addition, we conducted a usability testing procedure based on the think-aloud protocol. The results of this study enabled the timely identification of improvement opportunities for the graphical interface of the Yggdrasil graphical interface before the actual implementation.

This study aims to assess the frequency of the lingual foramina and canals relative to their location on the mandibular cortical plate and also to closely inspect the course of the lingual canals inside the mandibular body using 3D reconstruction of the evaluated area. A retrospective study was conducted with 55 cone bean computed tomography (CBCT) scans in order to analyze the location, number, course and anastomosing pattern of the lingual canals. A total number of 165 lingual canals (LCs) were recorded from 55 patients, as follows: 94 median (MLC), 16 paramedian (PLC) and 55 lateral lingual canals (LLC). MLCs were a constant finding in all 55 patients (100% of the cases), PLCs were present in 15 patients (27.3% of the cases), and LLCs were identified in 35 patients (63.3% of the cases). The anastomosing pattern of the MLC, in which a supraspinous canal anastomosed with an infraspinous canal, was found in 10.9% of the cases (6 of 55 patients),. The LLCs were anastomosed with the mandibular incisive canal (MIC) in 56.3% of the cases (31 of 55 LLCs) and with the mandibular canal (MC) in 3.6% of the cases (2 of 55 LLCs). CBCT revealed itself to be a reliable tool for evaluating the intramandibular topography of the LCs. The anastomosing pattern of the lingual canals might raise the question whether the LCs could be responsible for incomplete anesthesia after conventional mandibular block by carrying sensory innervation from the mylohyoid nerve to the inferior alveolar nerve.