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The emergence of collective order in matter is among the most fundamental and intriguing phenomena in physics. In recent years, the ultrafast dynamical control and creation of novel ordered states of matter not accessible in thermodynamic equilibrium is receiving much attention. Among those, the theoretical concept of dynamical multiferroicity has been introduced to describe the emergence of magnetization by means of a time-dependent electric polarization in non-ferromagnetic materials. In simple terms, a large amplitude coherent rotating motion of the ions in a crystal induces a magnetic moment along the axis of rotation. However, the experimental verification of this effect is still lacking. Here, we provide evidence of room temperature magnetization in the archetypal paraelectric perovskite SrTiO$_3$ due to this mechanism. To achieve it, we resonantly drive the infrared-active soft phonon mode with intense circularly polarized terahertz electric field, and detect a large magneto-optical Kerr effect. A simple model, which includes two coupled nonlinear oscillators whose forces and couplings are derived with ab-initio calculations using self-consistent phonon theory at a finite temperature, reproduces qualitatively our experimental observations on the temporal and frequency domains. A quantitatively correct magnitude of the effect is obtained when one also considers the phonon analogue of the reciprocal of the Einsten - de Haas effect, also called the Barnett effect, where the total angular momentum from the phonon order is transferred to the electronic one. Our findings show a new path for designing ultrafast magnetic switches by means of coherent control of lattice vibrations with light., Main text: 10 pages, 4 figures, methods and 8 supplemental figures

La crioconservazione in azoto liquido di gemme prelevate durante il riposo invernale è una tecnica innovativa di grande potenzialità per il mantenimento di varietà commerciali di specie da frutto. La collaborazione avviata tra il CAV di Faenza e il CNR-Ivalsa di Firenze ha l'obiettivo della duplicazione in criobanca delle accessioni attualmente in screen-house ed ha già prodotto preliminari, interessanti risultati con le gemme di varietà di melo.

Sharka, caused by Plum Pox Virus (PPV), is by far the most important infectious disease of peach [P. persica (L.) Batsch] and other Prunus species. The progressive spread of the virus in many important growing areas throughout Europe poses serious issues to the economic sustainability of stone fruit crops, peach in particular. The adoption of internationally agreed-upon rules for diagnostic tests, strain-specific monitoring schemes and spatial-temporal modeling of virus spread, are all essential for a more effective sharka containment. The EU regulations on nursery activity should be modified based on the zone delimitation of PPV presence, limiting open-field production of propagation materials only to virus-free areas. Increasing the efficiency of preventive measures should be augmented by the short-term development of resistant cultivars. Putative sources of resistance/tolerance have been recently identified in peach germplasm, although the majority of novel resistant sources to PPV-M have been found in almond. However, the complexity of introgression from related-species imposes the search for alternative strategies. The use of genetic engineering, particularly RNA interference (RNAi)-based approaches, appears as one of the most promising perspectives to introduce a durable resistance to PPV in peach germplasm, notwithstanding the well-known difficulties of in vitro plant regeneration in this species. In this regard, rootstock transformation to induce RNAi-mediated systemic resistance would avoid the transformation of numerous commercial cultivars, and may alleviate consumer resistance to the use of GM plants.

In un pereto commerciale nel quale era stata riscontrata resistenza di Stemphylium vesicarium ai dicarbossimidici e alle strobilurine, sono state condotte prove di campo pluriennali (dal 2007 al 2013) per valutare l’efficacia di questi fungicidi e, nel contempo, l’evoluzione della sensibilità del patogeno. Per quanto riguarda i dicarbossimidici, in situazioni di prevalenza di ceppi del patogeno resistenti, è emerso che la sospensione del loro impiego per 7 anni porta ad una regressione del fenomeno e al recupero dell'efficacia con un utilizzo limitato a 1-2 interventi per anno. Analogamente, la sospensione dell'impiego delle strobilurine, in situazioni di presenza diffusa di popolazioni con elevata frequenza di conidi resistenti, ha condotto alla regressione del fenomeno. Tuttavia il reinserimento di questi prodotti nella difesa aziendale non è stato ancora sperimentalmente valutato. Le verifiche condotte sul boscalid non hanno evidenziato né cali di efficacia in campo né riduzioni di sensibilità di S. vesicarium. APPLICATION OF SOME FUNGICIDES AND EVALUATION OF THE SENSITIVITY OF STEMPHYLIUM VESICARIUM STRAINS ON PEAR A multiyear trial (2007-2013) was carried out in a pear orchard where resistance of Stemphylium vesicarium to dicarboximides and stroblilurines had been detected in the previous years. At the same time, fruits were collected in plots to isolate the pathogen and evaluate the sensitivity towards dicarboximides and strobilurines. As for dicarboximides, in situations of prevalence of pathogen resistant strains, it was found that the suspension of their use for 7 years had led to a regression of pathogen resistance with a recovery of effectiveness when the products were used only once or twice a year. As for strobilurins, in situations of widespread presence of populations with high frequency of resistant conidia, the suspension of their use brought to the regression of the phenomenon. However, the re-insertion of these products in the defence strategy was not evaluated. As for boscalid, neither a decrease in effectiveness, nor a shift of sensitivity of S. vesicarium was observed.

The search for novel tools to control magnetism at the nanoscale is crucial for the development of new paradigms in optics, electronics and spintronics. So far, the fabrication of magnetic nanostructures has been achieved mainly through irreversible structural or chemical modifications. Here, we propose a new concept for creating reconfigurable magnetic nanopatterns by crafting, at the nanoscale, the magnetic anisotropy landscape of a ferromagnetic layer exchange-coupled to an antiferromagnetic layer. By performing localized field cooling with the hot tip of a scanning probe microscope, magnetic structures, with arbitrarily oriented magnetization and tunable unidirectional anisotropy, are reversibly patterned without modifying the film chemistry and topography. This opens unforeseen possibilities for the development of novel metamaterials with finely tuned magnetic properties, such as reconfigurable magneto-plasmonic and magnonic crystals. In this context, we experimentally demonstrate spatially controlled spin wave excitation and propagation in magnetic structures patterned with the proposed method.

Nel presente lavoro è stato applicato e convalidato il sistema AuthentiFOOD quale strumento innovativo per garantire l’autenticità di una filiera di un prodotto agroalimentare, in questo caso quella dei prosciutti tipici. A tal fine è stato scelto un tracciante naturale appropriato (farina di frumento) miscelato alla sugna che viene utilizzata durante la stagionatura dei prosciutti crudi. Tale tracciante, il cui codice genetico è caratteristico della varietà di frumento utilizzata, garantisce il Consorzio di tutela del prosciutto crudo da eventuali frodi commerciali. Basta infatti un semplice prelievo del tracciante dal prosciutto per valutare, attraverso l’analisi del DNA, l’autenticità del prosciutto stesso. Questo sistema di autenticazione/tracciabilità non altera le caratteristiche del prodotto, è semplice ed impossibile da imitare.

Bacterial meningitis is a life-threatening infection with a low recurrence rate. However, this possibility has always to be considered and avoided. This case report concerns a 5-year-old girl who was admitted in our Emergency Pediatric Unit for symptoms of bacterial meningitis and signs of disseminated intra-vascular coagulopathy. After a successful treatment the girl was discharged in good health. She was admitted to our hospital after one year with the same symptoms of meningitis. Laboratory examinations confirm the admittance suspect. An accurate research allowed to find out immunological deficiencies and showed an occult malformation, transethmoidal encephalocele, responsible for the recurrent meningitis. The present case suggests that the opportunity to perform an accurate cerebral imaging study (with special attention to the ethmoidal region and inner ear) in all cases of meningitis to detect occult anatomical alterations, thus preventing infectious recurrence, should always be taken into account.