Food forensics

The food market nowadays accounts for huge incomes and therefore it is an easy target for falsification. This recalls the urgency for reliable and powerful diagnostic techniques, in order to develop analytical protocols for identification of frauds. MS-based strategies of analysis are definitely suitable for this task and have become in the last years of paramount importance in the field of food forensics. Sophisticated techniques have been developed that request short times of analysis and allow the identification of specific parameters, useful as classification markers. The wide range of techniques available [i.e. isotopic analysis, inductively coupled plasma - mass spectrometry (ICP-MS), hyphenated systems, stand-alone systems] allow to address a wide range of analytical questions pertaining to food authentication and traceability

Fixation of genetic variation and optimization of gene expression: The speed of evolution in isolated lizard populations undergoing Reverse Island Syndrome

The ecological theory of island biogeography suggests that mainland populations should be more genetically divergent from those on large and distant islands rather than from those on small and close islets. Some island populations do not evolve in a linear way, but the process of divergence occurs more rapidly because they undergo a series of phenotypic changes, jointly known as the Island Syndrome. A special case is Reversed Island Syndrome (RIS), in which populations show drastic phenotypic changes both in body shape, skin colouration, age of sexual maturity, aggressiveness, and food intake rates. The populations showing the RIS were observed on islets nearby mainland and recently raised, and for this they are useful models to study the occurrence of rapid evolutionary change. We investigated the timing and mode of evolution of lizard populations adapted through selection on small islets. For our analyses, we used an ad hoc model system of three populations: wild-type lizards from the mainland and insular lizards from a big island (Capri, Italy), both Podarcis siculus siculus not affected by the syndrome, and a lizard population from islet (Scopolo) undergoing the RIS (called P. s. coerulea because of their melanism). The split time of the big (Capri) and small (Scopolo) islands was determined using geological events, like sea-level rises. To infer molecular evolution, we compared five complete mitochondrial genomes for each population to reconstruct the phylogeography and estimate the divergence time between island and mainland lizards. We found a lower mitochondrial mutation rate in Scopolo lizards despite the phenotypic changes achieved in approximately 8,000 years. Furthermore, transcriptome analyses showed significant differential gene expression between islet and mainland lizard populations, suggesting the key role of plasticity in these unpredictable environments

Shooting methods for a PT-symmetric periodic eigenvalue problem

We present a rigorous analysis of the performance of some one-step discretization schemes for a class of PT-symmetric singular boundary eigenvalue problem which encompasses a number of different problems whose investigation has been inspired by the 2003 article of Benilov et al. (J Fluid Mech 497:201-224, 2003). These discretization schemes are analyzed as initial value problems rather than as discrete boundary problems, since this is the setting which ties in most naturally with the formulation of the problem which one is forced to adopt due to the presence of an interior singularity. We also devise and analyze a variable step scheme for dealing with the singular points. Numerical results show better agreement between our results and those obtained from small-ε asymptotics than has been shown in results presented hitherto

Non invasive analysis of manuscript covers: portable X-ray Fluorescence enlighteningh medieval Jewellery masterpieces

AbstractThis paper will present portable X-ray fluorescence (pXRF) analysis applied in situ to three 11th- 12th century manuscripts covers considered as masterpieces of Northern Italy medieval jewellery: Pace di Ariberto (Milano), Liber Evangeliorium of Vercelli and Pace di Chiavenna. These objects show a sumptuous decoration of golden leaves, plates and filigrees, enamels and casted gems. The aim of this research is to obtain information on manufacturing techniques and composition of the artefacts, considering possible analogies and differences that may be useful for art historians’ discussion on manufacture place and artistic connections. XRF analysis was performed in order to determine the composition of the metals and enamels, and quantitative results, obtained using certified standards, undergo data treatment with multivariate analysis. The present paper will present a part of the results obtained on both the metals and glass materials, underlying the potential of pXRF in producing reliable results also when working in non-ideal conditions

Diagnosis of centrocestus formosanus infection in zebrafish (Danio rerio) in Italy: A window to a new globalization-derived invasive microorganism

Centrocestus formosanus is a digenetic trematode with a complex life cycle, involving invertebrate and vertebrate hosts, humans included. In particular, it causes gill lesions and mortality in freshwater fish species, and gastrointestinal symptoms in infected humans. Here, we describe the occurrence of C. formosanus infection in zebrafish imported in Italy and propose a newly designed species-specific primer pair to ameliorate the diagnostic investigations for C. formosanus. Gill arches of 30 zebrafish were examined for the presence of encysted metacercariae under a stereomicroscope and processed through molecular analyses targeting the ribosomal internal transcribed sequence 2 (ITS2). Although C. formosanus distribution was originally restricted to Asia, it has been subsequently reported in new countries, revealing itself as an invasive species and raising important concerns for biodiversity, economy, scientific research, as well as animal and public health. Given the crucial role played by the ornamental fish industry in spreading this parasite, there is an urgent need for control measures to prevent the introduction and establishment of C. formosanus in non-endemic areas, including Europe. We also suggest developing new strategies in microbiology and epidemiology to better explore this new globalization-derived invasive species

From Natural Woods to High Density Materials: An Ecofriendly Approach

Densified wood are a woody materials which an increase in density and mechanical properties. The materials obtained in this work, using less pollutant reagents, showed an increase in density from 200% to 400%. The characterizations determine the chemical and structural change compositions after every step. These characterizations showed how different woods have comparable densities and final mechanical properties (+300% the initial one) after densification process