Genetic authentication and traceability of food products of animal origin: new developments and perspectives

In recent years, both the demand and the supply for food of animal origin have experienced important changes making of fundamental importance the implementation of traceability systems. DNA analysis has the potential to overcome the limits of the conventional authentication and traceability procedures. Different levels can be considered: species identification, breed traceability, individual traceability, sex determination, and identification of genetically modified animals. DNA analysis for these levels makes use of endogenous DNA, i.e. DNA of animal origin that constitutes the fingerprinting of the animal itself or of its derived products. However, another source of DNA that can be analysed for authentication or traceability purposes is exogenous DNA, i.e. DNA added to the products that is not derived from the animals from which the products are obtained. Using exogenous DNA, other levels could be considered for traceability: year of production, consortium, farm, processing industry, etc. New technologies and innovative approaches are changing the way to consider and apply genetic authentication and traceability of food of animal origin. The advantages will be for both the consumers and producers creating added values for the animal production sector

Superfluid to Bose-glass transition in a 1D weakly interacting Bose gas

We study the one-dimensional Bose gas in spatially correlated disorder at zero temperature, using an extended density-phase Bogoliubov method. We analyze in particular the decay of the one-body density matrix and the behaviour of the Bogoliubov excitations across the phase boundary. We observe that the transition to the Bose glass phase is marked by a power-law divergence of the density of states at low energy. A measure of the localization length displays a power-law energy dependence in both regions, with the exponent equal to -1 at the boundary. We draw the phase diagram of the superfluid-insulator transition in the limit of small interaction strength.Comment: 4 pages, 4 figure

Spin control using chiral templated nickel

This Letter reports an original spin valve device that is based on a chiral templated nickel material. Chirality in Ni is induced by exploiting co-electrodeposition of an organic chiral template. In this specific case, the chiral templating is enantiopure tartaric acid (TA). Facile electrodeposition (co-deposition) in ambient conditions produces a nickel chiral-templated material. Z-shaped magnetoresistance curves, switching sign as a function of TA handedness, prove the peculiar ferromagnetic character induced by the presence of a chiral compound. Synchrotron measurements using circular polarized light, x-ray natural circular dichroism, confirm the chirality of the Ni in the TA/Ni composite. Density functional theory calculation proves the existence of a strong electronic delocalization involving the tartaric acid and Ni. The significant finding of this Letter is that chiral templated Ni paves the way for future spin valve, which will be able to control the spin without an external magnetic field (as indeed foreseen within the chiral induced spin selectivity-effect framework)

Mean-field phase diagram of the 1-D Bose gas in a disorder potential

We study the quantum phase transition of the 1D weakly interacting Bose gas in the presence of disorder. We characterize the phase transition as a function of disorder and interaction strengths, by inspecting the long-range behavior of the one-body density matrix as well as the drop in the superfluid fraction. We focus on the properties of the low-energy Bogoliubov excitations that drive the phase transition, and find that the transition to the insulator state is marked by a diverging density of states and a localization length that diverges as a power-law with power 1. We draw the phase diagram and we observe that the boundary between the superfluid and the Bose glass phase is characterized by two different algebraic relations. These can be explained analytically by considering the limiting cases of zero and infinite disorder correlation length.Comment: 10 pages, 10 figure

Quantum Phase Transition in a Low-Dimensional Weakly Interacting Bose Gas

This thesis is devoted to the study of the effect of disorder on low-dimensional weakly interacting Bose gases. In particular, the disorder triggers a quantum phase transition in one dimension at zero temperature that is investigated here through the study of the long-range behaviour of the one-body density matrix. An algebraic spatial decay of the coherence marks the quasicondensate, whereas, in the case of strong disorder, an exponential decay is recovered and it characterizes the insulating Bose-glass phase. This analysis is performed using an extended Bogoliubov theory to treat low dimensional Bose gases within a density-phase approach. A systematic numerical study allowed to draw the phase diagram of 1D weakly interacting bosons. The phase boundary obeys two different power laws between interaction and disorder strength depending on the regime of the gas where the transition occurs. These relations can be explained by means of scaling arguments valid in the white noise limit and in the Thomas-Fermi regime of the Bose gas. The phase transition to a quasicondensed phase comes along with the onset of superfluidity: the inspection of the superfluid fraction of the gas is consistent with these predictions for the boundary. The finite temperature case and the scenario in two dimensions are briefly discussed. The quantum phase transition is caused by low-energy phase fluctuations that destroy the quasi-long-range order characterizing the uniform system. Within the approach presented here, the phase fluctuations are identified as the low-lying Bogoliubov modes. Their properties have been investigated in detail to understand which changes trigger the phase transition and we found that the transition to the insulating phase is accompanied by a diverging density of states and a localization length, measured through the inverse participation ratio, that diverges as a power-law with power – 1 for vanishing energy. The fragmentation of the gas is also studied: this notion is very often associated with the onset of the insulating phase. The characterization of the density fragmentation is performed by analyzing the probability distribution of the density. A density profile is defined as fragmented when the probability distribution at vanishing density is finite or divergent and this happens for a gas in the Bose-glass phase. On the contrary, the superfluid phase is characterized by a zero limiting probability of having vanishing densities. This definition is derived analytically, and confirmed by a numerical study. This fragmentation criterion is particularly suited for detecting the phase transition in experiments: when a harmonic trap is included, the transition to the insulating phase can be extracted from the statistics of the local density distribution

Interazione luce-materia in microcavità basate su materiali organici con progressioni vibroniche

L'interazione luce-materia in microcavità contenenti materiali organici è oggetto di crescente interesse teorico e sperimentale per le sue caratteristiche di accoppiamento più forte rispetto ai tradizionali materiali inorganici. Le peculiarità che contraddistinguono i materiali organici sono inoltre una spiccata anisotropia e la frequente presenza di ripetizioni vibroniche nello spettro di assorbimento. L'obiettivo di questo lavoro è la stima delle proprietà ottiche di un tale sistema in microcavità. Per farlo sono stati utilizzati due approcci diversi uno quantistico e uno di carattere macroscopico. Il primo parte dalla trattazione quantistica degli elementi che coesistono nella cavità, gli eccitoni di Frenkel, le loro ripetizioni vibroniche e i fotoni di cavità (TE e TM), considerandone microscopicamente le interazioni così da calcolare gli autostati del sistema: i polaritoni di cavità. Le proprietà ottiche vengono successivamente analizzate nell'ipotesi di specchi quasi perfetti con il formalismo dei quasimodi che accoppia i polaritoni di cavità al continuo dei campi esterni. L'approccio macroscopico parte dalla caratterizzazione di un generico tensore dielettrico uniassiale e si basa sulla risoluzione delle equazioni di Maxwell per ricavare i modi del campo elettromagnetico nella cavità. Il formalismo usato per arrivare alle proprietà ottiche del sistema è quello della matrice di trasferimento 4X4 per sistemi stratificati omogenei anisotropi. Entrambi gli approcci partono da uno spettro di assorbimento che presenta una progressione vibronica, calcolato con il modello degli oscillatori armonici traslati per riprodurre la variazione delle configurazioni di equilibrio dei potenziali adiabatici dello stato fondamentale e del primo stato eccitato. Con questi modelli sono stati simulati i pochi spettri sperimentali disponibili (dovuti ad Holmes e Forrest) e sono stati analizzati altri casi riguardanti sistemi più complessi e generali come materiali monocristallini anisotropi o campioni con risonanze parzialmente in accoppiamento forte e debole

Investigation of a short interspersed nuclear element polymorphic site in the porcine vertnin gene: Allele frequencies and association study with meat quality, carcass and production traits in Italian Large White pigs

A 291 bp short interspersed nuclear element (SINE) insertion in the porcine vertnin (VRTN) gene on porcine chromosome 7 was shown to affect vertebral number and several production traits: allele Q (with the insertion) increases vertebral number compared to the wild type allele (WT, without insertion). In this study we genotyped this polymorphism in eight pig breeds (Italian Large White, Italian Duroc, Italian Landrace, Cinta Senese, Mora Romagnola, Casertana, Apulo Calabrese, and Nero Siciliano) and in Italian wild boars to evaluate allele frequency distribution of the two alleles. Allele Q was the most frequent in Italian Landrace and Italian Duroc (0.738 and 0.545, respectively) whereas it was the less frequent in all other breeds and was absent in wild boars. Association study was carried out in two Italian Large White samples. These two groups of animals were constituted by performance tested pigs for which estimated breeding values (EBV) and random residuals (RR) for several traits (average daily gain, back fat thickness, feed: gain ratio, lean cuts and ham weight) were calculated: i) 270 pigs chosen without any criteria (random group), that were also measured for several meat quality traits; ii) 560 gilts with extreme and divergent EBV for back fat thickness. For these animals vertebral number was not available. Results of the association analyses indicated that allele Q was associated with a lower ham weight, confirming indirectly, the negative correlation reported by other studies between vertebral number and this trait. No other trait was associated with the analysed VRTN polymorphism

CA22112 - European Network on Livestock Phenomics (EU-LI-PHE)

As animal breeding relies on the availability of accurate and specific phenotype data to reach its goals, phenotyping is increasingly being recognised as a limiting factor in all applications of livestock genetics and genomics. The acquisition of relevant phenotypes is also fundamental to routine and daily management of livestock populations in order to optimise reproduction strategies, disease control and welfare of the animals. Consequently, this knowledge gap needs to be filled to facilitate long-term improvement and a sustainable landscape for livestock production. Phenomics is emerging as a major new technical discipline in biology. Phenomics is focused on one major aim: to systematically describe the phenome, referred to as the physical and molecular traits of an organism. This discipline can be defined as the ensemble of methodologies and technologies for the acquisition, analysis and exploitation of high-dimensional phenotypic data on an organism-wide scale. EU-LI-PHE will create a Europe-centred multidisciplinary, interconnected and inclusive community of experts that will enhance scientific collaboration, catalyse developments, and transfer livestock phenomics concepts and applications to improve the sustainability and competitiveness of the European livestock production sector. The Action will provide i) an overview of phenotyping technologies and infrastructures for applications in livestock phenomics, ii) approaches and methods for genome to phenome integration in livestock species, iii) computational resources and data analysis methods needed for this big data discipline, iv) a regulatory framework and a societal vision on livestock phenomics and v) a training environment for the benefit of the next generation of researchers in this field. Action keywords Livestock - Genomics - Phenotype - Breeding - Big Dat

Honey Environmental DNA Can Be Used to Detect and Monitor Honey Bee Pests: Development of Methods Useful to Identify Aethina tumida and Galleria mellonella Infestations

Environmental DNA (eDNA) contained in honey derives from the organisms that directly and indirectly have been involved in the production process of this matrix and that have played a role in the hive ecosystems where the honey has been produced. In this study we set up PCR-based assays to detect the presence of DNA traces left in the honey by two damaging honey bee pests: the small hive beetle (Aethina tumida) and the greater wax moth (Galleria mellonella). DNA was extracted from 82 honey samples produced in Italy and amplified using two specific primer pairs that target the mitochondrial gene cytochrome oxidase I (COI) of A. tumida and two specific primer pairs that target the same gene in G. mellonella. The limit of detection was tested using sequential dilutions of the pest DNA. Only one honey sample produced in Calabria was positive for A. tumida whereas about 66% of all samples were positively amplified for G. mellonella. The use of honey eDNA could be important to establish early and effective measures to contain at the local (e.g., apiary) or regional scales these two damaging pests and, particularly for the small hive beetle, to prevent its widespread diffusion