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The morphology of molybdenum disulfide (MoS2) is a crucial aspect to ensure the functionality of this remarkable 2D-material both in electronic and tribological applications. Indeed, molybdenum dithiocarbamates (MoDTCs) can be tribochemically transformed into MoS2, which is able to reduce the friction coefficient of metallic moving parts. However, this transformation is influenced by temperature, sulfur/oxygen ratio, normal and shear stresses, making the mechanism of this process particularly challenging to explain. Ab initio simulations based on density functional theory (DFT), including a quantum mechanics/molecular mechanics (QM/MM) approach, are used here to shed light on the crystallization of MoS2 promoted by mechanical stresses. Chemistry plays an important role during the reorganization of the units of MoSx obtained from MoDTC, because sulfur and oxygen atoms tend to move outside of the amorphous layer, surrounding the molybdenum atoms and creating a structure that can crystallize into MoS2. Normal load and sliding have a synergistic effect in rearranging the amorphous units into a crystalline structure, as the former helps overcoming the energy barriers associated to bonds breaking and forming, while the latter allows misplaced atoms to be pulled towards the crystalline sites. A crystalline MoS2 was obtained by ab initio calculations below 1000 K.

Impairments of inhibitory circuits are at the basis of most, if not all, cognitive deficits. The impact of OPHN1, a gene associate with intellectual disability (ID), on inhibitory neurons remains elusive.We addressed this issue by analyzing the postnatal migration of inhibitory interneurons derived from the subventricular zone in a validated mouse model of ID (OPHN1-/y mice). We found that the speed and directionality of migrating neuroblasts were deeply perturbed in OPHN1-/y mice. The significant reduction in speed was due to altered chloride (Cl-) homeostasis, while the overactivation of the OPHN1 downstream signaling pathway, RhoA kinase (ROCK), caused abnormalities in the directionality of the neuroblast progression in mutants. Blocking the cation-Cl- cotransporter KCC2 almost completely rescued the migration speed while proper directionality was restored upon ROCK inhibition. Our data unveil a strong impact of OPHN1 on GABAergic inhibitory interneurons and identify putative targets for successful therapeutic approaches.

Echinococcosis/hydatidosis is a parasitic zoonosis caused in humans by the larval stage of the Echinococcus granulosus cestode. Although notification of infestation is required, there are no reliable data on the prevalence of this parasitosis among humans in Italy. This zoonosis was first reported in ancient times (Hippocrates, fourth century BC) and since then many cases of echinococcosis/hydatidosis have been described. Currently, it is considered one of the main parasitoses affecting animals bred for income and one of the most important parasitic zoonoses. We present the clinical case of a three-year-old child, living in Palermo with a dog in his house, who came to our observation for dyspnea occurring after physical exercise. Diagnosis of echinococcosis was performed on the operating table and by histological examination. The case presented is special in its manifestation from a clinical point of view, because the young patient experienced multiple injuries only to lungs, without involvement of other organs and, although the left lung cysts appeared fissured on the operating table, our patient never presented immunoallergic disorders

Adhesion energy, a measure of the strength by which two surfaces bind together, ultimately dictates the mechanical behavior and failure of interfaces. As natural and artificial solid interfaces are ubiquitous, adhesion energy represents a key quantity in a variety of fields ranging from geology to nanotechnology. Because of intrinsic difficulties in the simulation of systems where two different lattices are matched, and despite their importance, no systematic, accurate first-principles determination of heterostructure adhesion energy is available. We have developed robust, automatic high-throughput workflow able to fill this gap by systematically searching for the optimal interface geometry and accurately determining adhesion energies. We apply it here for the first time to perform the screening of around a hundred metallic heterostructures relevant for technological applications. This allows us to populate a database of accurate values, which can be used as input parameters for macroscopic models. Moreover, it allows us to benchmark commonly used, empirical relations that link adhesion energies to the surface energies of its constituent and to improve their predictivity employing only quantities that are easily measurable or computable.

Phosphorene possesses a great potential for tribological applications due to its layered structure and for the capability of phosphorus to reduce friction and adhesion in steel–steel contacts. Here we present a comprehensive analysis of the static tribological properties of phosphorene based on first principles calculations. The most suitable exchange-correlation functional for describing the structural and electronic properties of multilayer phosphorene is carefully selected. The interlayer binding energy and shear strength are then calculated for two relative orientations of the layers. Layers stacked with the same orientation (armchair–armchair and zigzag–zigzag) are slippery as common solid lubricants, as MoS2 and graphite. While the armchair–zigzag orientation shows a remarkable superlubricity, with a reduction of one order of magnitude for the shear stress. We uncover the microscopic origin of such superlubric phase by analyzing the electronic charge at the layer interface.

We present a comprehensive ab initio, high-throughput study of the frictional and cleavage strengths of interfaces of elemental crystals with different orientations. It is based on the detailed analysis of the adhesion energy as a function of lateral, γ(x, y), and perpendicular displacements, γ(z), with respect to the considered interface plane. We use the large amount of computed data to derive fundamental insight into the relation of the ideal strength of an interface plane with its adhesion. Moreover, the ratio between the frictional and cleavage strengths is provided as good indicator for the material failure mode – dislocation propagation versus crack nucleation. All raw and curated data are made available to be used as input parameters for continuum mechanic models, benchmarks, or further analysis.

Herein, the potential of Fourier transform infrared spectroscopy (FTIR) spectroscopy coupled with principal component analysis and artificial neural networks to discriminate butters obtained from milk creams collected in different seasons (spring, summer or winter) and produced from two feeding regimens (traditional or unifeed) in the Parmigiano Reggiano cheese area was investigated. The predictive ability of neural networks to predict the season of production was 100%. The favorable results obtained by artificial neural network (ANN) analysis were in agreement with those reported by principal component analysis (PCA) analysis. The ability of ANNs to predict the feeding regimens was 90.0%, 75.0% and 75.0%, respectively, for samples collected in spring, summer and winter. These results also confirm that the method is highly suitable for its intended purpose. Highlights ► 405 FT-IR spectra of butter were analyzed by PCA and ANN. ► ANN discriminate the season of production and dietary regimen of butters. ► The ability of ANN to predict the season of production of milk cream was 100%.

The seasonal variation of the fatty acids composition of butters were investigated over three seasons during a 12-month study in the protected designation of origin Parmigiano-Reggiano cheese area. Fatty acids were analyzed by GC-FID, and then computed by artificial neural networks (ANN). Compared with spring and winter, butter manufactured from summer milk creams showed an optimal saturated/un-saturated fatty acids ratio (−8.89 and −5.79%), lower levels of saturated fatty acids (−2.63 and −1.68%) and higher levels of mono-unsaturated (+5.50 and +3.45%), poly-unsaturated fatty acids (+0.65 and +0.17%), and rumenic acid (+0.55 and +3.41%), while vaccenic acid had lower levels in spring and higher in winter (−2.94 and +2.91%). Moreover, the ANN models were able to predict the season of production of milk creams, and classify butters obtained from spring and summer milk creams on the basis of the type of feeding regimens. Practical applications: The investigation on variables that affect the milk fatty acids composition can improve the quality of milk across all systems, and the combination of chromatographic and computational techniques will ensure a secure traceability enabling producers to characterize dairy products.

BACKGROUND: Bovine milk contains hundreds of diverse components, including proteins, peptides, amino acids, lipids, lactose, vitamins and minerals. Specifically, the lipid composition is influenced by different variables such as breed, feed and technological process. In this study the fatty acid and phospholipid compositions of different samples of butter and its by-products from the Parmigiano Reggiano cheese area, produced by industrial and traditional churning processes, were determined. RESULTS: The fatty acid composition of samples manufactured by the traditional method showed higher levels of monounsaturatedandpolyunsaturatedfatty acids comparedwithindustrialsamples.Inparticular, thecontentsofn-3fatty acids and conjugated linoleic acidswere higher in samples produced by the traditionalmethod than in samples produced industrially. Sample phospholipid composition also varied between the two technological processes. Phosphatidylethanolamine was the majorphospholipidincream,butterandbuttermilksamplesobtainedbytheindustrialprocessaswell as increamandbuttermilk samples from the traditional process, while phosphatidylcholine was themajor phospholipid in traditionally produced butter. This result may be explained by the different churning processes causing different types of membrane disruption. Generally, samples produced traditionally had higher contents of total phospholipids; in particular, butter produced by the traditional method had a total phospholipid content 33% higher than that of industrially produced butter. CONCLUSION: The samples studied represent the two types of products present in the Parmigiano Reggiano cheese area, where the industrial churning process iswidespread compared with the traditional processing of Reggiana cow’s milk. This is because Reggiana cow’s milk production is lower than that of other breeds and the traditional churning process is time-consuming and economically disadvantageous.However, its products have been demonstrated to contain more bioactive lipids compared with products obtained from other breeds and by the industrial process.

La realtà del mercato internazionale del burro viene affrontata in un'ottica di filiera evidenziando le tendenze evolutive in tutti i suoi segmenti, dall'industria di trasformazione ai consumi, senza trascurare il commercio estero ed i canali distributivi. Trattandosi di una commodity derivata dal latte si è ritenuto utile inquadrare il mercato del burro nel contesto europeo ed internazionale dell'intero settore lattiero-caseario, al fine di meglio interpretarne le dinamiche. L'elevata volatilità dei prezzi registrata negli ultimi anni ha prodotto effetti destabilizzanti sui mercati ed ha innescato un processo di aggiustamento che ha dilatato i margini distributivi. Nell'ultima parte del lavoro viene affrontato il problema del posizionamento del prodotto in esame in rapporto alla GDO.