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Scrapie is an ovine transmissible spongiform encephalopathy, and its susceptibility is associated with polymorphisms in the prion protein gene (PRNP). Genetic selection is currently the most effective mean for eradication of the susceptible VRQ allele in favour of resistant ARR allele. Maintenance of genetic diversity should be one of the major objectives in breeding programmes, especially in endangered breeds, and genetic information are an excellent alternative to pedigree data where these information are missing. The aim of our study was to determine changes of genetic variability in six native sheep breeds from autonomous province of Bolzano, northern Italy, following simulation of scrapie selection scenarios. A total of 684 rams were investigated for PRNP polymorphisms and for 10 microsatellite loci to estimate genetic variability. Across all loci, a total of 163 alleles were detected with a mean of 10.4 alleles per locus. Average observed (Ho) and unbiased expected (uHe) heterozygosity overall loci were 0.74 and 0.78, respectively, showing a statistically significant deviation from Hardy-Weinberg equilibrium (HWE) in all breeds. This heterozygosity deficit was confirmed by a positive fixation index (Fis), determining a moderate inbreeding in each breed. Simulating a soft selection, where only rams having at least a VRQ allele should be excluded from reproduction, Ho, uHe and Fis values remained almost unchanged, indicating that genetic variability should not be affected by the removal of these individuals. With a mild selection scenario, considering only rams with at least one ARR allele, we observed a decrease in the mean alleles per breed (8.9) and the maintenance of heterozygosity deficiency, except for two breeds, where it was any longer significant. These results showed that selection strategies allowing use of heterozygous as well homozygous ARR rams might be the right compromise to improve resistance to scrapie and to do not dramatically affect genetic variability of these breeds.

Vespa velutina Lepeletier, 1836 (Hymenoptera: Vespidae), the yellow-legged hornet, is a social wasp native to North of India, China and tropical and subtropical areas of Southeast Asia. Adults are predators of a wide variety of arthropods, including honey bees. Vespa velutina has been unintentionally introduced in southwestern France before 2004 and its widely spreading across the country was followed by an impressive colonization of several areas within mainland Europe and overseas. In Italy, V. velutina has been officially reported in June 2013 in Imperia province, Liguria region (northern Italy) and is now well established in the western part of this region and occasionally reported in Piedmont region. More recently, it has been spotted in Veneto, Lombardy and Tuscany regions. In order to investigate the phylogenetic relationships and the origin of Italian V. velutina nigrithorax specimens, we performed a phylogenetic analysis of thirty-three samples, collected in 2012, 2016, 2017 and 2018 from different sites (Veneto, Piedmont and Liguria regions) based on mitochondrial cytochrome c oxidase subunit 1 (cox1) gene sequence analysis. The phylogenetic analysis as well the haplotypes study confirmed the placement of 33 Italian specimens within a cluster containing the other European samples plus Chinese specimens collected in Jiangsu and Zhejiang. Our results strongly supported the view that the Italian specimens of V. velutina nigrithorax derived from the spreading southward of the V. velutina nigrithorax population initially established in France, which is also moving northward (Belgium, The Netherlands, Germany, United Kingdom).

Single-crystalline silicon is well known to be a poor thermoelectric material due to its high thermal conductivity. Most excellent research has focused on ways to decrease its thermal conductivity while retaining acceptably large power factors (PFs). Less effort has been spent to enhance the PF in poly and nanocrystalline silicon, instead. Here we show that in boron-hyperdoped nanocrystalline thin films PF may be increased up to 33 mW K$^{-2}$m$^{-1}$ at 300 K when hydrogen embedded in the film during deposition is removed. The result makes nanocrystalline Si a realistic competitor of Bi$_2$Te$_3$ for low-temperature heat harvesting, also due to its greater geo-availability and lower cost.

The use of non-Saccharomyces yeast for wine making is becoming a common trend in many innovative wineries. The application is normally aimed at increasing aromas, glycerol, reducing acidity, and other improvements. This manuscript focuses on the reproduction of the native microbiota from the vineyard in the inoculum. Thus, native selected yeasts (Hanseniaspora uvarum, Metschnikowia pulcherrima, Torulaspora delbrueckii, Starmerella bacillaris species and three different strains of Saccharomyces cerevisiae) were inoculated sequentially, or only S. cerevisiae (three native strains together or one commercial) was used. Inoculations were performed both in laboratory conditions with synthetic must (400 mL) as well as in industrial conditions (2000 kg of grapes) in red winemaking in two different varieties, Grenache and Carignan. The results showed that all the inoculated S. cerevisiae strains were found at the end of the vinifications, and when non-Saccharomyces yeasts were inoculated, they were found in appreciable populations at mid-fermentation. The final wines produced could be clearly differentiated by sensory analysis and were of similar quality, in terms of sensory analysis panelists’ appreciation.

Water-based nanoparticles (NPs) of semiconducting polymers received considerable attention for optoelectronic and biological applications due to their simple preparation method, and their tunable optical properties.1 NPs are appealing for optoelectronic devices such as organic photovoltaic devices (OPVs),2 organic light-emitting diodes (OLEDs),3 and organic field-effect transistors (OFETs)4 to control the morphology of the active layer that plays a crucial role in the device performance. The NPs dispersion can be obtained through the miniemulsion method, using great amount of surfactants to ensure NPs stability. This approach allows for lowering the chlorinated solvent amount used in the active layer fabrication reducing the environmental payback of the devices, but to achieve good performances the excess of surfactant has to be removed at the end of the process.5 Amphiphilic block copolymers (BCPs) are a powerful tool to produce nanostructured or supramolecular objects with enhanced properties for electronics, optoelectronics, sensors and biotechnological applications because of their capability to self-assembly, influenced by the physico-chemical differences between the blocks, including the relative block length, block polarity, volume fraction, chain flexibility, etc.6 PCPDTBT-b-P4VP is an amphiphilic rod-coil BCP constituted by a low band-gap copolymer, PCPDTBT as the rigid segment, and tailored segments of poly-4-vinylpyridine (P4VP). The rod block was studied as donor material in hybrid and organic devices, whilst P4VP is able to interact with acceptor materials, as fullerene derivatives.7 Taking advantage of hydrophilic behavior of the coil, we studied the capability of PCPDTBT-b-P4VP to form NPs dispersion in aqueous medium through miniemulsion method, neat or in blend with fullerene derivatives, without use of surfactants avoiding purification steps. The NPs were optically, morphologically (AFM, TEM, Synchrotron XRD) and electrically characterized, showing suitable properties for the preparation of active layers and they were tested in eco-friendly NP-based OPVs with efficiency reaching over 2%.

Organic Memory Devices (OMD's) are a relatively new class of organic semiconductors devices which appear highly attractive due to their potential application in data storage. Blends of several organometallic compounds, lanthanide (Ln3+) beta-diketonate complexes (Ln3+= Eu3+, Gd3+, Sm 3+) in poly(vinyl)carbazole have been investigated as promising candidates for OMD. A single layer cell is obtained by an active layer sandwiched between two electrodes (ITO and Al). It was found experimentally that devices exhibited two distinctive bistable conductivity states, and are then suitable as WORM (Write Once Read Many) memory devices, only if the chemical structure of the ligand used was able to allow the reduction of the Ln3+ ion with the formation of charge transfer complexes. It is also noteworthy to note that a proper choice of the electrodes was able to change the intrinsic characteristic of the memory device then a flash rewritable memory can be obtained. A complete characterization and a deep investigation of the properties and performances of different materials as memory devices will be presented. Moreover the role of the different Ln3+ ions will be discussed.

During the past ten years, the field of organic electronics has witnessed giant step forwards. Light emitting diodes, photovoltaic cells and transistor based on organic material have in fact aroused considerable interest because of the unique advantages provided by the these materials like low fabrication cost, high mechanical flexibility and versatility of the chemical structures [1],[2]. In this field, another emerging, promising but still at the exploration stage research area is that of electronic organic memories [3]. An organic memory device stores information in a manner entirely different from that of silicon devices. Rather than encoding "0" and "1" as the amount of charge stored in a cell, organic memory stores data, for instance, based on the high and low conductivity response to an applied voltage (electrical bistability). The conductance switching has been attributed from time to time to different mechanism ranging from trappingdetrapping phenomena [4] to conformational change [5], from charge transfer [6] to filamentary conduction [7]. Anyway despite large efforts in the scientific community, the mechanism and the intriguing behaviour of electrical bistability and memory switching is still far from being completely understood. In particular it was believed that material structure and morphology can affect significantly the origin of the switching mode. However a systematic study on establishing the relationships between chemical structure, material morphology and memory characteristic has not fully exploited yet. Up to now different memory devices based on organic molecules were investigated in order to obtain the realization of an high performances memory devices for industrial application. One of the best results has been obtained with a blend between Poly(N-vinyl carbazole) (PVK) (Fig. 1 (D)), a semiconducting polymer, and some organolanthanide complexes but a clear explanation of their behaviour and functioning are still lacking. In this work we investigate the resistance switching phenomenon in a series of organometallic compound reported in Fig. 1 (B) and (C). In these complexes we maintain phenantroline as ancillary ligand while we change both the lanthanide ions (Gd3+, Sm3+, Eu3+) and the ionic ligand structure by using a Thienoyltrifluoroacetone (TTA) (an asymmetric ligand) or 1,3-Di-(2-Thienyl)-1,3-Propanedione (DPA) (a symmetric ligand). The architecture of the devices based on indium-thin-oxide (ITO)/PVK:rare earth complex/Al is also reported in Fig. 1(A). By variation of the lanthanide ion and ligands a large number of different devices with an ITO/organic layer/Al configuration were studied. In Fig. 2 the I-V characteristic curves relative to ITO/PVK:Gd(Phen)(DTP)3/Al (panel A), ITOPVK:Gd(Phen)(TTA)3/Al (panel B) have been reported as an example. For the ITO/PVK:Gd(Phen) (DTP)3/Al it can be seen (Fig. 2, panel A) that the current increases progressively with the bias voltage and is high (high-conductance state, ON state). As the voltage is increased further, a sharp decrease in the current from 10-1 to 10-4 A occurs at about 11 V, and the current keeps the low-conductance state (OFF state) with the current to decrease to 0, indicating the transition of the devices from the ON state to OFF state.