The AFLATOX® Project: Approaching the Development of New Generation,Natural-Based Compounds for the Containment of the Mycotoxigenic Phytopathogen Aspergillus flavus and Aflatoxin Contamination

The control of the fungal contamination on crops is considered a priority by the sanitary authorities of an increasing number of countries, and this is also due to the fact that the geographic areas interested in mycotoxin outbreaks are widening. Among the different pre- and post-harvest strategies that may be applied to prevent fungal and/or aflatoxin contamination, fungicides still play a prominent role; however, despite of countless efforts, to date the problem of food and feed contamination remains unsolved, since the essential factors that affect aflatoxins production are various and hardly to handle as a whole. In this scenario, the exploitation of bioactive natural sources to obtain new agents presenting novel mechanisms of action may represent a successful strategy to minimize, at the same time, aflatoxin contamination and the use of toxic pesticides. The Aflatox^® Project was aimed at the development of new-generation inhibitors of aflatoxigenic Aspergillus spp. proliferation and toxin production, through the modification of naturally occurring molecules: a panel of 177 compounds, belonging to the thiosemicarbazones class, have been synthesized and screened for their antifungal and anti-aflatoxigenic potential. The most effective compounds, selected as the best candidates as aflatoxin containment agents, were also evaluated in terms of cytotoxicity, genotoxicity and epi-genotoxicity to exclude potential harmful effect on the human health, the plants on which fungi grow and the whole ecosystem.     

Aspects of nucleosomal positional flexibility and fluidity

Nucleosomes have been considered until recently to be stable and uniquely localized particles. We focus here on two properties of nucleosomes that are emerging as central attributes of their functions: mobility and multiplicity of localization. The biological relevance of these phenomena is based on the fact that chromatin functions depend on the relative stability of nucleosomes, on their covalent or conformational modifications, their dynamics, their localization, and the density of their distribution. In order to understand these complex behaviors both the structure of the nucleosome core particles and the informational rules governing their interaction with defined DNA sequences are here taken into consideration. The fact that nucleosomes solve the problem of how to locate a specific interaction site on a potentially infinite combination of sequences, with interactions recurring to a controlled level of informational ambiguity and stochasticity, is discussed. Nucleosomes have been shown to slide along DNA. This novel facet of their behavior and its implications in chromatin remodeling are reviewed.     

Tabu search-based metaheuristic algorithm for software system reliability problems

This paper presents a new metaheuristic-based algorithm for complex reliability problems. The algorithm effectively uses features of the Tabu Search paradigm, with special emphasis on the exploitation of memory-based mechanisms. It balances intensification with diversification via the use of short-term and long-term memory. The algorithm has been thoroughly tested on benchmark problems from the literature as well as on a pool of random generated instances of very large scale software systems. The proposed algorithm proves to be robust with respect to its parameters and it is especially suited for very large scale instances of the reliability problem, when exact approaches are doomed to fail.     

A covert attention P300-based brain-computer interface: Geospell

The Farwell and Donchin P300 speller interface is one of the most widely used brain-computer interface (BCI) paradigms for writing text. Recent studies have shown that the recognition accuracy of the P300 speller decreases significantly when eye movement is impaired. This report introduces the GeoSpell interface (Geometric Speller), which implements a stimulation framework for a P300-based BCI that has been optimised for operation in covert visual attention. We compared the Geospell with the P300 speller interface under overt attention conditions with regard to effectiveness, efficiency and user satisfaction. Ten healthy subjects participated in the study. The performance of the GeoSpell interface in covert attention was comparable with that of the P300 speller in overt attention. As expected, the effectiveness of the spelling decreased with the new interface in covert attention. The NASA task load index (TLX) for workload assessment did not differ significantly between the two modalities. PRACTITIONER SUMMARY: This study introduces and evaluates a gaze-independent, P300-based brain-computer interface, the efficacy and user satisfaction of which were comparable with those off the classical P300 speller. Despite a decrease in effectiveness due to the use of covert attention, the performance of the GeoSpell far exceeded the threshold of accuracy with regard to effective spelling.     

A Sensitivity-Based Design Space Exploration Methodology for Embedded Systems

In this paper, we propose a system-level design methodology for the efficient exploration of the architectural parameters of the memory sub-systems, from the energy-delay joint perspective. The aim is to find the best configuration of the memory hierarchy without performing the exhaustive analysis of the parameters space. The target system architecture includes the processor, separated instruction and data caches, the main memory, and the system buses. To achieve a fast convergence toward the near-optimal configuration, the proposed methodology adopts an iterative local-search algorithm based on the sensitivity analysis of the cost function with respect to the tuning parameters of the memory sub-system architecture. The exploration strategy is based on the Energy-Delay Product (EDP) metric taking into consideration both performance and energy constraints. The effectiveness of the proposed methodology has been demonstrated through the design space exploration of a real-world case study: the optimization of the memory hierarchy of a MicroSPARC2-based system executing the set of Mediabench benchmarks for multimedia applications. Experimental results have shown an optimization speedup of 2 orders of magnitude with respect to the full search approach, while the near-optimal system-level configuration is characterized by a distance from the optimal full search configuration in the range of 2%.     

The proton iron-sulfur cluster environment of the [FeFe]-hydrogenase maturation protein HydF from Thermotoga neapolitana

[FeFe]-hydrogenases contain a complex [4Fe–4S]-2Fe cluster (H-cluster) and are able to efficiently reduce protons to H₂. Due to their potential exploitation for renewable energy production biotechnologies, significant efforts have been put into understanding the mechanisms driving the H-cluster assembly, which involves three conserved proteins. Among them, HydF works as scaffold upon which the H-cluster precursor is synthesized and carrier to deliver it to the hydrogenase, resulting in its activation. A FeS cluster binding sequence (CxHx₄₆-₅₃HCxxC) is conserved in all HydF proteins and should in principle provide four ligands to coordinate the Fe atom. However, we found that alternative metal coordination may exist in different HydF proteins and that only the three cysteines are strictly required, whereas the fourth ligand may vary and is, in any case, readily exchangeable. In this work we analyzed by EPR/HYSCORE the FeS cluster proton environment of HydF from Thermotoga neapolitana to determine the possible role of surrounding residues in the non-cysteinyl iron ligation of the protein.     

Memory,narrative and display – city museums in recent initiatives and debates

Currently, the study and the exhibition of the history and artistic traces of city development are gaining new interest. Several Italian and European cities are proposing, or have just established, organisations or museums intended to ‘display’ their past. Recently a research group has been constitued at the University IUAV of Venice based on the premiss that a contemporary City Museum has to be a conduit for knowledge to a large and varied public including, on equal terms: citizens, immigrants, tourists and people with cultural and professional interests in the urban environment. In this sense Venice seems to be a very good clase‐study. While an important initiative, such as the constitution of a new Museum of the twentieth century in Mestre (the mainland of Venice) is going on, the research group thinks that this kind of institution, within the framework of a very complex and rich system of museums, such as the Venetian one, could have a wide remit. In fact, one of the special key issues for Venice in the twentieth century has been opening up its cultural and productive activities to the external world. Foreigner visitors, as well as many citizens have always had the vision of Venice as a medieval and renaissance city with a very old historical centre. Yet in the course of the twentieth century, the urban settlement had greatly changed in a very interesting and innovative way. This has to be explained and shown to both tourists and the Venetians.     

Aquaporins Are One of the Critical Factors in the Disruption of the Skin Barrier in Inflammatory Skin Diseases

The skin is the largest organ of the human body, serving as an effective mechanical barrier between the internal milieu and the external environment. The skin is widely considered the first-line defence of the body, with an essential function in rejecting pathogens and preventing mechanical, chemical, and physical damages. Keratinocytes are the predominant cells of the outer skin layer, the epidermis, which acts as a mechanical and water-permeability barrier. The epidermis is a permanently renewed tissue where undifferentiated keratinocytes located at the basal layer proliferate and migrate to the overlying layers. During this migration process, keratinocytes undertake a differentiation program known as keratinization process. Dysregulation of this differentiation process can result in a series of skin disorders. In this context, aquaporins (AQPs), a family of membrane channel proteins allowing the movement of water and small neutral solutes, are emerging as important players in skin physiology and skin diseases. Here, we review the role of AQPs in skin keratinization, hydration, keratinocytes proliferation, water retention, barrier repair, wound healing, and immune response activation. We also discuss the dysregulated involvement of AQPs in some common inflammatory dermatological diseases characterised by skin barrier disruption.     

LC with Evaporative Light-Scattering Detection for Quantitative Analysis of Organic Acids in Juices

In this work, a performing LC method with evaporative light-scattering detector was described for the analysis of tartaric, malic, ascorbic, citric and succinic acids in fruit juices. The method was optimized and validated in comparison with LC-UV, in terms of accuracy, LODs, LOQs and precision. The successive application to ACE, orange, pear, peach, mulberry and apple juices allowed separation and quantitative determination of organic acids in about 20 min just diluting and filtering the sample before LC determination. In the analysed juices, citric, malic and ascorbic acids were always present, and in all the samples, citric acid was the prevailing acid followed by malic acid except for peach and apple juices where an opposite trend was found. Tartaric and succinic acids were detected at lower concentrations and more rarely, except for peach juices, all containing tartaric acid, and ACE and orange juices, all containing succinic acid.