Tactile identification of embossed lines and square areas in diverse dot heights by blind individuals

Universal Access in the Information Society - Most of the braille embossers incorporate a mode for the creation of braille embossed graphics (BEG). Some of them can produce dots in different...     

Effect of salts and sugars on the clarity of gellan gels

The effect of glucose, fructose and sucrose (0–15 wt%) on the clarity of low acyl gellan gels (0.5 wt%) in the presence of potassium chloride (40–100 mm ), calcium chloride (10–80 mm ) and their mixtures at a total molar concentration of 80 mm , was investigated by light absorbance experiments (490 nm). The effect on gel clarity (at 100 mm KCl) of all sugar combinations, at a final concentration of 15 wt%, was also investigated. All gels with potassium were less turbid than the ones with calcium. In the case of salt mixtures, increasing concentration of calcium in the mixtures resulted in decreased clarity. In addition, turbidity increased with increasing salt concentration. Moreover, and at the higher salt concentrations, the presence of sugars resulted in clearer gels. When mixtures of sugars were added, all combinations resulted in increased clarity compared to the individual sugars.     

Design and Tracing of Post-Byzantine Churches in the Florina Area, Northwestern Greece

This paper constitutes an effort to investigate the application of specific design and constructional tracing in post-Byzantine churches situated in northwestern Greece, mainly in the wider area of the town of Florina and the Prespa Lakes, covering a period from the fifteenth to the nineteenth century. Firstly, a review of the relevant previous studies concerning the investigation of proportions and constructional tracing in Byzantine churches is presented. Secondly, a brief analysis of the metric systems of the Byzantine and the Ottoman period is given in order to define the applied modules. Furthermore, the typology of post-Byzantine churches is analysed. The main part of the paper includes the investigation of the constructional grid and the proportions in several plan drawings, in combination with the use of triangular tracing (right triangles). The analysis is also extended to fa?ades and sections, in order to demonstrate the standardisation of the construction. Apart from the above, the application of the golden section in some examples is also examined. Finally, conclusions are drawn concerning the design and application of models and tracing on the construction of post-Byzantine churches.     

The Use of the Module, Metric Models and Triangular Tracing in the Traditional Architecture of Northern Greece

This paper presents the analysis of the design and construction of the traditional houses in northern Greece and the correlation with the use of the metric system of the architect’s cubit and the existence of architectural tracing and proportions. Of particular significance is the detection of certain metric models widely applied in the urban centres of northern Greece during the nineteenth century, and the general application of the Pythagorean theorem on the triangular tracing. The analysis was based on the application of the functional and constructional module on plans and fa?ades of houses in order to investigate its influence on the standardisation of the design of the spaces and their elements, as well as of the construction. This makes it possible to reconstruct the design principles that characterise the traditional houses in the Ottoman Empire and the proportions of their parts, as well as to identify similarities and differences between the various urban centres of northern Greece. Another finding of the research involves the way in which the structural grid is applied to the design of the fa?ades and to the placement of the structural elements and the openings of the timber-frame construction. As a result, conclusions are drawn concerning the role and the effect of the measuring system and the various metric models on the constructional rationale and on the development of the form of the traditional house.     

A New Paradigm of Crystallization Arising from Non-standard Nucleation Pathways

There is increasing evidence that large classes of colloid materials crystallize via a non-standard nucleation mechanism involving intermediate metastable phases. In this paper recent work on the microscopic derivation of the phase diagram and free energy barriers in the nucleation of protein crystals, and on the kinetics of growth of solid particles in the post-nucleation regime is reviewed. The extent to which combined structural and density fluctuation give rise to favourable crystallization pathways involving an intermediate fluid phase is assessed and the connection with experiments in microgravity at ISS (PROMISS-2 and NANOSLAB-2) is discussed.