André Goffeau's imprinting on second generation yeast “genomologists”

All authors of the present paper have worked in labs that participated to the sequencing effort of the Saccharomyces cerevisiae reference genome, and we owe to this the fact that we have all chosen to work on genomics of yeasts. S. cerevisiae has been a popular model species for genetics since the 20th century as well as being a model for general eukaryotic cellular processes. Although it has also been used empirically in fermentation for millennia, there was until recently, a lack of knowledge about the natural and evolutionary history of this yeast. The achievement of the international effort to sequence its genome was the foundation for understanding many eukaryotic biological processes but also represented the first step towards the study of the genome and ecological diversity of yeast populations worldwide. We will describe recent advances in yeast comparative and population genomics that find their origins in the S. cerevisiae genome project initiated and pursued by André Goffeau.     

The budding yeast life cycle: More complex than anticipated?

The budding yeast, Saccharomyces cerevisiae, has served as a model for nearly a century to understand the principles of the eukaryotic life cycle. The canonical life cycle of S. cerevisiae comprises a regular alternation between haploid and diploid phases. Haploid gametes generated by sporulation are expected to quickly restore the diploid phase mainly through inbreeding via intratetrad mating or haploselfing, thereby promoting genome homozygotization. However, recent large population genomics data unveiled that heterozygosity and polyploidy are unexpectedly common. This raises the interesting paradox of a haplo‐diplobiontic species being well‐adapted to inbreeding and able to maintain high levels of heterozygosity and polyploidy, thereby suggesting an unanticipated complexity of the yeast life cycle. Here, we propose that unprogrammed mating type switching, heterothallism, reduced spore formation and viability, cell–cell fusion and dioecy could play key and uncharted contributions to generate and maintain heterozygosity through polyploidization.     

A new methodology in the study of PVAc‐based adhesive formulations

The role of the main components of a PVAc‐based wood adhesive formulation in the formation and performance of the adhesive joint was investigated. A new analytical methodology was applied to carry out the chemical separation and characterization of the adhesive components present in the bond line. By using extraction techniques on the wet and dry glues it was possible to observe the variation in the solubility of the adhesive components, for different glue formulations. The swollen‐state NMR technique proved to be a very useful tool to characterize the insoluble parts present in the adhesive films. These findings, when put into relation to some specific properties of the adhesive joints, contribute to the understanding of the mechanisms involved in the adhesion process. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Fail-safe point fixing of structural glass. New advances

The intrinsic brittleness of glass renders its architectural use in monolithic panels quite problematic. For this reason, glass plies are usually laminated with polymeric interlayers that can maintain coherent fragments after glass breakage, so avoiding sudden collapse (fail-safe response). However, the safety performance disappears if the connection to the rear load-bearing structure is not able to retain the panels in their place after glass breakage. To this aim, an innovative point-fixing system for frameless glass glazing has been developed, that exploits the enhanced mechanical properties of a new generation of ionoplast polymer interlayers. Bending tests on small scale glass beams have been performed at various levels of loading, temperature and aging. Laminated glass connected with the new device exhibit a noteworthy resistance and interesting post-glass-breakage performances.     

Comparison of the characterisation of the fruit‐like aroma of Teucrium flavum L. subsp flavum by hydrodistillation and solid‐phase micro‐extraction

BACKGROUND: Teucrium species (Lamiaceae) are interesting for the food industry since many of them are used in the preparation of flavoured wines and beers, herbal teas, bitters and liqueurs. On this basis, the analysis of the aroma components of Teucrium flavum L. subsp. flavum growing in central Italy was carried out by means of both hydrodistillation (HD) and headspace solid‐phase micro‐extraction (HS‐SPME), coupled with GC/FID and GC/MS. RESULTS: A total of 102 components were identified in the essential oils, representing 99.0‐99.3% of the total oils. Sesquiterpenes hydrocarbons constituted the major fraction (48.5–49.4%), with the apple‐like flavour (Z,E)‐α‐farnesene being the major component. HS‐SPME allowed the analysis of the volatiles not only emitted by specific plant parts, but also by different parts within a single flower: flower calyx afforded the highest contribution, in terms of volatiles, to the aroma of the plant. CONCLUSION: The chemical profile of the volatile fraction obtained by HD and HS‐SPME, demonstrated the plant fruit‐like aroma, confirming the usefulness for flavouring wines, bitters and other kind of beverages, and also suggested other applications, as aroma and taste enhancer in food processing. In particular, SPME resulted in a very useful technique, which permits a choice between the part of the plant which has the highest concentration of a specific fragrance, and therefore establishes the best way of sampling during industrial applications of aromatic plants. Copyright © 2009 Society of Chemical Industry     

Dealing with trajectory streams by clustering and mathematical transforms

Nowadays, almost all kind of electronic devices leave traces of their movements (e.g. smartphone, GPS devices and so on). Thus, the huge number of this “tiny” data sources leads to the generation of massive data streams of geo-referenced data. As a matter of fact, the effective analysis of such amounts of data is challenging, since the possibility to extract useful information from this peculiar kind of data is crucial in many application scenarios such as vehicle traffic management, hand-off in cellular networks, supply chain management. Moreover, spatial data streams management poses new challenges both for their proper definition and acquisition, thus making the overall process harder than for classical point data. In particular, we are interested in solving the problem of effective trajectory data streams clustering, that revealed really intriguing as we deal with sequential data that have to be properly managed due to their ordering. We propose a framework that allow data pre-elaboration in order to make the mining step more effective. As for every data mining tool, the experimental evaluation is crucial, thus we performed several tests on real world datasets that confirmed the efficiency and effectiveness of the proposed approach.     

Retrieving the Coassembly Pathway of Composite Cellulose Nanocrystal Photonic Films from their Angular Optical Response

Aqueous suspensions of cellulose nanocrystals (CNCs) are known to self-assemble into a chiral nematic liquid crystalline phase, leading to solid-state nanostructured colored films upon solvent evaporation, even in the presence of templating agents. The angular optical response of these structures, and therefore their visual appearance, are completely determined by the spatial arrangement of the CNCs when the drying suspension undergoes a transition from a flowing and liquid crystalline state to a kinetically arrested state. Here, it is demonstrated how the angular response of the final film allows for retrieval of key physical properties and the chemical composition of the suspension at the onset of the kinetic arrest, thus capturing a snapshot of the past. To illustrate this methodology, a dynamically evolving sol–gel coassembly process is investigated by adding various amounts of organosilica precursor, namely, 1,2-bis(trimethoxysilyl)ethane. The influence of organosilica condensation on the kinetic arrest can be tracked and thus explains the angular response of the resulting films. The a posteriori and in situ approach is general; it can be applied to a variety of additives in CNC-based films and it allows access to key rheological information of the suspension without using any dedicated rheological technique.     

Surface‐functionalized polyurethane nanoparticles for targeted cancer therapy

Polymer nanoparticles (nps) have gained growing interest as carriers for anticancer drugs as they can target tumour tissues by both passive and active pathways. While the passive targeting mechanisms mainly rely on the small size of the carriers, active targeting requires surface modifications of the polymer core in order to introduce specific functionalities to actively recognize cancer cells. The present work proposes an innovative method for the preparation of surface‐functionalized nps based on the use of biodegradable polyester‐ and polyester/ether‐urethanes (PURs) embedding amino functionalities. Two polyurethanes were prepared, one based on just poly(?‐caprolactone) diol (PCL‐PUR) and the other based on both PCL diol and poly(ethylene glycol) (PEG) (70/30 ratio, PCL‐PEG‐PUR). Nanoparticles of small size ranging between 150 and 200 nm and negative ζ potential (ranging from ?18 mV to ?27 mV) were obtained. Functional groups were exposed post nps preparation as confirmed by X‐ray photoelectron spectroscopy, ninhydrin assay and ¹H NMR, which evidenced a 24% tert‐butyloxycarbonyl cleavage for PCL‐PUR‐NH₂ nps and 29% for PCL‐PEG‐PUR‐NH₂ nps. The monoclonal antibody Herceptin (HER), which targets HER‐2 receptors, was coupled through ethyl(dimethylaminopropyl) carbodiimide/N‐hydroxysuccinimide (EDC/NHS) mediated chemistry. The optimal HER:NH₂ ratio was determined to be 1:16 for the PEG‐containing PUR and 1:8 for PCL‐PUR. HER‐nps maintained the intrinsic cytotoxicity of the antibody, as shown by the ca 50% decrease of HER‐2‐expressing HeLa cell viability. The results indicate that our protocol for surface functionalization of PUR nps, based on surface exposure of previously inserted functional groups followed by covalent coupling of biomolecules, is suitable for the preparation of nps for active recognition of target cells. © 2016 Society of Chemical Industry     

Effect of oxygen reduction during malaxation on the quality of extra virgin olive oil (Cv. Carboncella) extracted through “two-phase” and “three-phase” centrifugal decanters

Quality and composition of virgin olive oil (VOO) are strictly dependent on complex processes that take place during the olive fruit crushing and malaxation of the olive paste. In this work, modulation of O₂ levels within malaxation chambers (R1: unmodified atmosphere; R2: oxygen: 12.73–4.64 kPa from the beginning to the end of malaxation; R3: 10.46–2.27 kPa; R4: 9.87–0.69 kPa) in two continuous “two-phase” and “three-phase” oil extraction plants was performed. Combined effects on the biosynthesis of nutritionally bioactive molecules and aroma volatiles and on the resulting sensory properties of the produced oils were investigated. Results showed that the type of oil extraction plant markedly affected the level of the phenolic compounds in the oil (and the related sensory attributes of bitter, pungency, astringency and bitter and pungency persistence). Reduction of O₂ concentration in the malaxing chamber, while having a minor impact on the presence of phenolic compounds, significantly affected the formation of all the examined volatiles. Particularly, lowered levels of oxygen hindered the formation of lipoxygenase derived volatiles weakening odours and flavours of artichoke, fresh fruity, and fresh cut grass.