CFD investigation on the aerodynamic interferences between medium-solidity Darrieus Vertical Axis Wind Turbines

The present study contributes to understand physical mechanisms involved in an achievable power enhancement by setting vertical axis wind turbines in close proximity. The turbines are straight-bladed Darrieus micro-turbines characterized by medium-high solidity and therefore low tip-speed ratio. Preliminary CFD simulations of the isolated turbine explain the reasons why it has a low power output, namely which are laminar flow and laminar separation bubbles on the blades. This fact is expected also considering the low Reynolds number. Subsequently a campaign of CFD simulations has been performed to analyse the aerodynamic interferences in two-rotor configurations. The behaviour of counter-rotating and co-rotating arrangements is analysed at different distances between rotor axes. The simulations show an increasing of power production of about 10% compared to results for the isolated turbine, independently of the sense of rotation. In order to verify wheter vortex shedding suppression might be the cause of the enhanced performance interactions has been simulated between two closely spaced Magnus spinning cylinders with the same tip-speed ratio of the turbines. These last results don’t show reasonable analogies with VAWT wake structures and interactions. Our main conclusion is that accelerated free-stream flow between the turbines is the principle cause of the power extraction enhancement by means of contraction and re-energisation of the turbine wakes. CFD predictions of a four-rotor configuration confirm our hypothesis, nevertheless the wind direction strongly affects the overall efficacy

Impact of TiO2 nanoparticles on Vicia narbonensis L.: potential toxicity effects

This work was aimed to provide further information about toxicology of TiO2 nanoparticles (NPs) on Vicia narbonensis L., considering different endpoints. After exposure to TiO2 nanoparticle suspension (mixture of rutile and anatase, size <100 nm) at four different concentrations (0.2, 1.0, 2.0 and 4.0 ‰), the seeds of V. narbonensis were let to germinate in controlled environmental conditions. After 72 h, the extent of the success of the whole process (seed germination plus root elongation) was recorded as the vigour index, an indicator of possible phytotoxicity. After the characterisation of the hydric state of different materials, oxidative stress and enzymatic and nonenzymatic antioxidant responses were considered as indicators of possible cytotoxicity and to assess if damage induced by TiO2 NPs was oxidative stress-dependent. Cytohistochemical detection of in situ DNA fragmentation as genotoxicity endpoint was monitored by TUNEL reaction. The treatments with TiO2 NPs in our system induced phytotoxic effects, ROS production and DNA fragmentation. The nonenzymatic and enzymatic antioxidant responses were gradually and differentially activated and were able to maintain the oxidative damage to levels not significantly different from the control. On the other hand, the results of DNA fragmentation suggested that the mechanisms of DNA repair were not effective enough to eliminate early genotoxicity effects

Atrophic pseudarthrosis of humeral diaphyseal fractures: medico-legal implications and methodological analysis of the evaluation

Humeral shaft fractures account for 1- 3% of all fractures and about 20-27% of those involving the humerus. In the past they were often conservatively treated, with an acceptable consolidation rate. Open reduction and internal fixation (ORIF) is the best choice in polytrauma patients, in complex or pathological fractures and in those associated with vascular injuries. Regardless the type of fixation used, these fractures can evolve into delayed union or pseudarthrosis (PSA). It should be noted that the humeral shaft itself has a high intrinsic healing potential, due to the blood supply provided by the surrounding muscles. The aim of this work is to evaluate whether the causes that led to the development of atrophic pseudarthrosis in a humeral diaphyseal fracture are attributable to inadequate management of this fearful complication and to highlight the possible medico-legal repercussions. We will try to verify whether the currently used forensic evaluation parameters of permanent disability are appropriate and adequate in relation to the complexity of such injuries. This complexity also includes the repercussions on the ergonomic efficiency of the entire limb, the relative possible postural alterations, the inevitable extension of the period of traumatic illness and the relative repercussions on the overall compromised structure of the subject

Novel Polydiacetylene-Functionalized Nanostructures for Sensing Applications

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A novel in-frame deletion in MYOT causes an early adult onset distal myopathy

Missense mutations in MYOT encoding the sarcomeric Z-disk protein myotilin cause three main myopathic phenotypes including proximal limb-girdle muscular dystrophy, spheroid body myopathy, and late-onset distal myopathy. We describe a family carrying a heterozygous MYOT deletion (Tyr4_His9del) that clinically was characterized by an early-adult onset distal muscle weakness and pathologically by a myofibrillar myopathy (MFM). Molecular modeling of the full-length myotilin protein revealed that the 4-YERPKH-9 amino acids are involved in local interactions within the N-terminal portion of myotilin. Injection of in vitro synthetized mutated human MYOT RNA or of plasmid carrying its cDNA sequence in zebrafish embryos led to muscle defects characterized by sarcomeric disorganization of muscle fibers and widening of the I-band, and severe motor impairments. We identify MYOT novel Tyr4_His9 deletion as the cause of an early-onset MFM with a distal myopathy phenotype and provide data supporting the importance of the amino acid sequence for the structural role of myotilin in the sarcomeric organization of myofibers

Identification of a targetable KRAS-mutant epithelial population in non-small cell lung cancer

Lung cancer is the leading cause of cancer deaths. Tumor heterogeneity, which hampers development of targeted therapies, was herein deconvoluted via single cell RNA sequencingin aggressive human adenocarcinomas (carrying Kras-mutations) and comparable murine model. We identified a tumor-specific, mutant-KRAS-associated subpopulation which is conserved in both human and murine lung cancer. We previously reported a key role for the oncogene BMI-1 in adenocarcinomas. We therefore investigated the effects of in vivo PTC596 treatment, which affects BMI-1 activity, in our murine model. Post-treatment, MRI analysis showed decreased tumor size, while single cell transcriptomics concomitantly detected near complete ablation of the mutant-KRAS-associated subpopulation, signifying the presence of a pharmacologically targetable, tumor-associated subpopulation. Our findings therefore hold promise for the development of a targeted therapy for KRAS-mutant adenocarcinomas

Sensor Radars with Subset Diversity

Sensor radars enable new important applications. Their localization capability is challenged by wireless propagation conditions, which can be mitigated by employing diversity techniques. We introduce subset diversity (SSD) radars that exploit diverse spatial and temporal propagation conditions for the selected sensors measurements. A framework for analysis and design of SSD sensor radars is developed, jointly considering (i) network setting, (ii) propagation environment, (iii) sensor measurements, and (iv) localization techniques. As a case study, we consider ultrawide bandwidth (UWB) sensor radars with subset diversity in a typical indoor environment. Results enable a clear understanding of how network setting affects the passive localization performance

La Olivetti Synthesis a Massa: una piccola Ivrea tra le Apuane e il mare

Risale al 1939 l’idea di localizzare a Massa, nella Zona Industriale Apuana (Z.I.A.), uno stabilimento Olivetti per la produzione dei suoi schedari e classificatori metallici. Tra il 1941 e il 1942, viene realizzato il primo corpo di fabbrica, il serbatoio dell’acqua, la cabina elettrica, la recinzione con la pensilina d’ingresso e il locale della pesa. Il progetto è di Piero Bottoni e Mario Pucci, che concepiscono uno stabilimento a misura d’uomo armoniosamente inserito nel contesto paesaggistico. Nel 1949, terminata la guerra, riprendono i lavori e lo stabilimento viene messo in funzione