Endocytic pathways and membrane recycling involve the actin filaments in tobacco pollen tubes

The pollen tube is a tip growing cell that plays a fundamental role in the fertilization process of higher plants. Pollen tube growth is based on transport and accumulation of secretory vesicles. The incorporation of new segments of PM largely exceeds the quantity of membrane required for the extension, so the excess of PM must be removed by endocytosis. Recent studies showed internalization of subapical PM domains that were mainly recycled to exocytosis through the Golgi apparatus and a second mainly degradative pathway involving PM retrieval at the tip. The movements of the endomembrane system during the pollen tube growth depends on the concerted action and integrity of the cytoskeleton. In this study we disturb the system of cortical actin filaments using Latrunculin B to verify modifications in endocytosis, using specific FM dyes in time-lapse experiments and by ultrastructural experiments using charged Nanogold. Our results demonstrate that the system of cortical microfilaments determines a strong reduction of endocytosis in the subapical regions and consequently the alteration of recycling through the Golgi and the inhibition of the degradative pathways

Men’s reactions to gender inequality in the workplace: From relative deprivation on behalf of women to collective action

: Over recent years, the role of men as women's allies in the struggle for gender equality has become increasingly important. Previous research has shown that often men do not fight gender inequalities as they fail to recognize the severity of discrimination against women (e.g., in hiring). In this study (N = 427), we examined whether men who experienced relative deprivation on behalf of women-a form of relative deprivation that stems from the awareness that women hold a less privileged position in society-were more motivated to engage in collective action to support gender equality in the workplace. The findings showed that men's feelings of deprivation on behalf of women were associated with a greater willingness to engage in collective action for gender equality. This relationship was sequentially mediated by two emotional reactions related to deprivation-increased guilt about gender inequalities and decreased fear of a potential backlash-and the moral conviction of acting for gender equality. These results suggest that men's awareness of gender inequality at work is an important antecedent to their acting in solidarity with women and that emotions and moral conviction are two psychological processes that turn cognition into behavior. Action to reduce gender inequalities should make men more sensitive to seeing that they hold a privileged position in society and to recognizing the pervasive and harmful nature of women's deprivation

Brassica spp cover crop affects soil microbial activity, carbon and nitrogen nutrient dynamics

A general positive effect of Brassica on soil microbial biomass and its activity was observed at all European sites in no tilled soil at both sampling date. Conversely, Brassica under tillage may produce a negative effect on biochemical properties after CC suppression. The effect of Brassica on C and N dynamics differed among the european sites when soil was tilled. These preliminary results establish the bases for the evaluation of the interaction between the pedoclimatic conditions and Brassica spp effect on soil properties

Local seismic response studies in the north-western portion of the August 24th, 2016 Mw 6.0 earthquake affected area. The case of Visso village (Central Apennines).

In this work, we investigate the possible causes of the differential damaging observed in Visso village (Central Apennines, about 28 km north from the August 24th, 2016 Mw 6.0 earthquake epicenter). Following insights from the available geological cartography at 1:10.000 scale, a preliminary geophysical survey has been performed in the damaged area in order to constrain geometries and extent of the subsoil lithotypes. Then, these results have been used to retrieve a Vs profile close to the most heavily damaged buildings. This latter has been used as input for a numerical analysis aimed at deriving the motion at the ground level in the study area. In particular, a linear equivalent simulation has been performed by means of EERA code and the waveform has been obtained convolving the time history recorded during the August 24th, 2016 mainshock at Spoleto Monteluco (SPM) site. Our preliminary results indicate a possible correlation of damaging to the thickness and shape of the geological units. Nevertheless, further analyses are necessary to highlight any 2D basin and / non- linear soil behaviour effects in order to compare them to the intrinsic buildings vulnerability, according to the EMS98 guidelines

Preliminary tests on PEG-based thermoresponsive polymers for the production of 3D bioprinted constructs

In the last years, the growing demand for tissues and organs led to the development of novel techniques, such as 3D bioprinting. This technique proved to be promising for both patient-specific and custom-made applications when using autologous cells, and for the creation of standardized models that in the future could be used for instance for high-throughput drug screening. Within this context, the formulation of bioinks that could provide reliable, reproducible, and replicable structures with good mechanical properties and high biocompatibility is a crucial challenge. In this work, the use of a thermoresponsive PEG-based formulation was investigated as a bioink, allowing its use for 4D bioprinting applications triggered by thermal changes. First, the polymer was synthesized by reversible addition-fragmentation chain transfer polymerization (RAFT), which allows for optimal control over the final properties of the polymer. Then, the printability for extrusion-based bioprinting of this formulation was assessed through in-situ imaging. Finally, the use of this polymer as bioink was tested by encapsulation of endothelial cells and evaluating cell distribution within the construct

In-situ monitoring of defects in extrusion-based bioprinting processes using visible light imaging

Tissue engineering techniques are central for the development of biomedical scaffolds, which are primarily employed in the biofabrication of various artificial human tissue and organ models. Bioprinting is a new technique of creating tissue constructs that can sustain cell proliferation. The development of printing techniques proceeds together with the development of the biomaterials to be printed, which is why studying the printability of these specific biomaterials must be explored. An appropriate hydrogel used as bioink should have numerous rheological, mechanical, and biological properties for producing appropriate tissue constructs. However, reaching the right trade-off between a desirable bioactivity and high printability is challenging, and despite numerous optimization studies for different materials, printing defects often occur during printing. Herein, methods are proposed to automatically identify these drifting processes in commonly used geometries and how they affected subsequent layers, as well as printing defects within each layer. Several structures were printed with standard commercial bioink as proof of concept. The constructs were analyzed using optical images from a coaxial camera. The images were then digitally processed to get geometrical data from which patterns of defectology to be monitored were derived. This automation should decrease the time in post-processing characterization of constructs and should provide a standardized tool to compare different bioinks