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Accurate material characterization of soft tissues is crucial for understanding the physiopathology of cardiovascular diseases. However, commercial biaxial testing systems are expensive, prompting the need for affordable custom solutions. This study aimed to develop a low-cost custom biaxial system capable of accurately characterizing the mechanical behavior of soft tissues. The biaxial system was constructed using 3D printing technology and non-captive linear actuators for precise displacement control. A real-time marker tracking system was implemented to estimate dis-placements without the need for costly hardware. The system's performance was evaluated through tests on a calibration spring and frozen porcine aorta samples. The linear actuators demonstrated excellent response to user position input after motor tuning, showing no discrepancies between commands and actual positions. The experimental testing of the calibration spring showed good agreement with the analytical solution, validating the system's ability to accurately test materials. Testing on porcine aorta samples revealed stress–strain responses consistent with existing literature, accounting for potential variations due to tissue preservation and regional material property heterogeneity. Overall, this custom biaxial system demonstrates promising performance in accurately assessing the mechanical behavior of soft tissues, providing researchers with a valuable tool for cardiovascular disease research and tissue engineering applications.

Ptilostemon greuteri is one of the most endangered and poorly studied woody vascular plant species of the Mediterranean Basin, endemic to Sicily (Italy). Several peculiar traits confer to P. greuteri a character of uniqueness and an enigmatic attractiveness. In fact, at first glimpse the largest individuals of this species remind the most remarkable and peculiar cases of herbaceous genera (e.g., Echium, Senecio) turned woody on insular or insular-like mountain ecosystems. Following the discovery of a second population of this rare species, a project aiming at the study and conservation of P. greuteri was set up. We present here updated information on the distribution, conservation status, biology and ecological requirements of this species. Field surveys supported by drone imagery were carried out to estimate the current range of the two populations. The data obtained allowed to refine the conservation status assessment of the species and to update the distribution pattern of P. greuteri by means of detailed digital maps of each population. Ongoing field investigations currently provide valuable information about the ecological requirements of the species and point out the impact of wildfires on population size and structure. Our research has also highlighted several knowledge gaps that need to be filled to apply more effective conservation measures. Preliminary results suggest that local topographic and mesoclimatic factors (air humidity and shade) are key variables explaining the persistency and survival of P. greuteri in the area.

The growth of Zelkova abelicea (Lam.) Boiss. (Ulmaceae), a tree species endemic to the island of Crete (Greece), was studied within 31 fenced plots protected from browsing during three years after fencing across the entire distribution range of the species. Potential geographic, edaphic, climatic and physiognomic factors that could influence shoot elongation and height increase were investigated for each plot. We found that trees grew twice as much within the same period of time in western and central Crete compared to trees from eastern Crete. In addition, taller trees grew more than shorter individuals. Although some variation was found within the soil parameters, and particularly sites situated on slopes were distinguishable from sites situated in flat dolines, none of the soil parameters was found to be significant in explaining growth differences amongst Z. abelicea trees of different mountain ranges. Precipitation and temperature were interpolated for each plot from an existing network of 49 weather stations on Crete. Our analyses showed that the plots were distributed along a longitudinal, westwards increasing gradient in precipitation as well as along an altitudinal gradient in temperature. Our analyses revealed that geographical position on the island, precipitation in June and initial tree height were significant in explaining spatial differences in Z. abelicea growth. Our results underline the importance of spring and early summer climatic conditions in determining Z. abelicea growth and highlight differences throughout the island.

As occurred on many other small Mediterranean islands, agricultural activity at Lampedusa (Strait of Sicily) underwent a very strong decline in terms of surface area during the second half of the last century. In particular, cereal crops have ceased and horticulture is disappearing, while vineyards still occupy a reduced area but are quickly vanishing and currently survive thanks to a small number of old farmers. Here are presented the results of a research carried out by interviewing seven farmers in order to study not only the techniques and the germplasm used in local viticulture, but also the final use of grapes and an evaluation on the connection between traditional farming and agro-ecosystems plant species-richness. Vines were grown for wine, to produce fresh and sun-dried grapes, or to preserve them in alcohol. Several names of the local varieties suggest that they might have been introduced in Lampedusa from the neighbouring territories: being fishermen and farmers at the same time, local people had trade relationships with other Mediterranean areas such as Tunisia, Malta and Southern Italy. Furthermore, local farming plays a key role in plant conservation. In fact, the disappearance of agricultural systems is leading to the extinction of 43 plant species, some of them considered rare not only on the local level, but also on the regional and national one. Because of the small size of farmland and its fragmentation, local agriculture cannot be supported by the European Community. Therefore, in order to safeguard local viticulture, special systems of assistance and new managing policies - focused on rural development plans and showing which concrete actions are necessary and feasible to protect the agroecosystems - are needed.