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Green sustainability is becoming more and more an issue in the management of urban greening. Accordingly, the use of native species of wild flora is increasing in urban greenspace design and restoration ecology because of their capacity of adaptation to adverse local environmental conditions and support long-term persistence of ecosystem recovery. Although the use of peat-free growing media is increasing in professional nursery, due to the environmental concerns around peat bogs exploitation, the use of materials suitable to replace peat in the growing medium is poorly investigated for the production of wild plants. In this work, we investigated the biomass production and the reproductive performances of eight native species (Agrostis stolonifera, Carex pendula, Dianthus carthusianorum, Iris pseudacorus, Leucanthemum vulgare, Lychnis flos-cuculi, Lythrum salicaria and Scabiosa graminifolia) and two ornamental species (Deschampsia caespitosa and Verbena bonariensis) in four different growing media (peat:pumice 70:30 v/v as a control; coconut coir dust:pumice 70:30v/v; coconut coir dust:green compost 55:45 v/v; coconut coir dust:green compost:stabilized wood fibre 40:30:30 v/v). Biomass accumulation and biometric indicators were assessed during blooming period, by measuring above-ground biomass, below-ground biomass, total biomass and, for a subset of species, number of flowering stems and number of flowers. Whilst plants grown in green compost and coconut coir dust media generally tended to have same biomass and comparable reproductive performances of plants grown in peat-based medium (with only one exception; i.e. Verbena bonariensis), plants grown in wood fibre media showed lower biomass accumulation, although not always (not all species) statistically significant. Green compost and coconut coir dust represented excellent substitutes of peat for the cultivation of native herbaceous plants in commercial nursery.

This paper compares different control strategies of the synchronous reluctance motor to outline their impact on the accuracy of flux-observer based sensorless operation. Maximum torque per ampere, maximum efficiency, and maximum power factor controls, usually referred to optimize the operating performance of synchronous reluctance motors are considered. Alternative solutions not usual in literature but specifically investigated for supporting the estimation are also considered, namely constant direct-axis-current and constant direct-axis-flux controls. The flux-observer detects the flux components in the two-phase stationary reference frame by a non-linear model achieved by finite-elements computations. An auxiliary mechanical observer who accounts for the finite-elements mapping of the torque is adjusted by the flux estimation error and provides the rotor position and speed needed for sensorless control. An extended set of experimental tests is presented where the different control methods are compared in terms of position and speed estimation errors and overall control quality. A four poles, three kW synchronous reluctance prototype designed for general industry application is used for testing.

Living organisms often display adaptive strategies that allow them to move efficiently even in strong confinement. With one single degree of freedom, the angle of a rotating bundle of flagella, bacteria provide one of the simplest examples of locomotion in the living world. Here we show that a purely physical mechanism, depending on a hydrodynamic stability condition, is responsible for a confinement induced transition between two swimming states in E. coli. While in large channels bacteria always crash onto confining walls, when the cross section falls below a threshold, they leave the walls to move swiftly on a stable swimming trajectory along the channel axis. We investigate this phenomenon for individual cells that are guided through a sequence of micro-fabricated tunnels of decreasing cross section. Our results challenge current theoretical predictions and suggest effective design principles for microrobots by showing that motility based on helical propellers provides a robust swimming strategy for exploring narrow spaces., Most biological and artificial self-propelled particles tend to be attracted by solid walls on their swimming pathways. Vizsnyiczai et al. show that, unexpectedly, confining E. coli cells inside a channel triggers stable locomotion along the channel axis once the channel is narrower than a critical value.

The centromere is a fundamental chromosome structure in which the macro-molecular kinetochore assembles and is bound by spindle microtubules, allowing the segregation of sister chromatids during mitosis. Any alterations in kinetochore assembly or functioning or kinetochore–microtubule attachments jeopardize chromosome stability, leading to aneuploidy, a common feature of cancer cells. The spindle assembly checkpoint (SAC) supervises this process, ensuring a faithful segregation of chromosomes. CENP-E is both a protein of the kinetochore and a crucial component of the SAC required for kinetochore–microtubule capture and stable attachment, as well as congression of chromosomes to the metaphase plate. As the function of CENP-E is restricted to mitosis, its haploinsufficiency has been used to study the induced cell aneuploidy, however, the gene expression profile triggered by CENP-E reduction in normal cells has never been explored. To fill this gap, here we investigated whether a gene network exists that is associated with an siRNA-induced 50% reduction in CENP-E and consequent aneuploidy. Gene expression microarray analyses were performed at early and late timepoints after transfection. Initially, cell cycle regulation and stress response pathways were downregulated, while afterwards pathways involved in epithelial–mesenchymal transition, hypoxia and xenobiotic metabolism were altered. Collectively, our results suggest that CENP-E reduction triggers a gene expression program that recapitulates some features of tumor cells.

Image Correlation techniques are increasing in popularity and are now suitable to investigate complex structural and fluid-dynamics of cardiovascular systems. These approaches operate through a digital correlation of a pair of images to determine physical quantities of complex systems. In this thesis, their application to the mechanical characterisation of complex biomaterials (Nitinol and soft materials), and the characterisation of complex biofluid-dynamics was investigated, with the aim to analyse their reliability and enhance their accuracy and field of application. Digital Image Correlation, supported by Infrared Thermography, was used to achieve a more in depth understanding of the mechanical behaviour of Nitinol shape memory alloys. The analysis led to the design of a new approach that minimise the error of standard characterisation methods. Application of DIC to soft materials focused on biaxial test protocols commonly adopted in their characterisation. These were investigated, identifying major drawbacks that reduce the accuracy of the results. A new setup arrangement of easy implementation was developed to reduce the source of errors from above 50% to below 20%. For the characterisation of complex biofluid-dynamics, a new Particle Image Velocimetry (PIV) approach was attempted to improve the current estimation of the Effective Orifice Area (the leading parameter in heart valves characterisation) by allowing its direct measurement. Previously unreported limitations in the application of PIV to the analysis of the fluid-dynamics in complex cardiovascular cases were identified and investigated by implementing a new approach based on the use of SPH (Smoothed-particle hydrodynamics) Synthetic Images. Image correlation techniques were also used to address another experimental issue typical of PIV applications in cardiovascular engineering, the refractive index mismatch between blood equivalent test fluid and the anatomical phantoms. In particular, a new blood equivalent was developed, with similar density and viscosity as human blood at body temperature. This has same refractive index as a new optically transparent silicone (FER-7061), for which a prototyping protocol was implemented. In summary, this thesis presents a range of studies focused on applications of digital image correlation to cardiovascular engineering, making a distinct contribution to the state of knowledge in the area by identifying main limitations of the different methods and proposing new original approaches that allow to minimise them, to better support the development and assessment of safer and more effective cardiovascular solutions.

Sperm motility is a prerequisite for male fertility. Enhancing the concentration of motile sperms in assisted reproductive technologies - for human and animal reproduction - is typically achieved through aggressive methods such as centrifugation. Here we propose a passive technique for the amplification of motile sperm concentration, with no externally imposed forces or flows. The technique is based upon the disparity between probability rates, for motile cells, of entering in and escaping from complex structures. The effectiveness of the technique is demonstrated in microfluidic experiments with microstructured devices, comparing the trapping power in different geometries. In these micro-traps we observe an enhancement of cells concentration close to 10, with a contrast between motile and non-motile increased by a similar factor. Simulations of suitable interacting model sperms in realistic geometries reproduce quantitatively the experimental results, extend the range of observations and highlight the ingredients that are key to optimal trap design.

Uncontrolled cell proliferation is a hallmark of cancer as a result of rapid and deregulated progression through the cell cycle. The inhibition of cyclin-dependent kinases (CDKs) activities is a promising therapeutic strategy to block cell cycle of tumor cells. In this work we reported a new example of nanocomposites based on halloysite nanotubes (HNTs)/pyrazolo[3,4-d]pyrimidine derivatives (Si306 and Si113) as anticancer agents and CDK inhibitors. HNTs/Si306 and HNTs/Si113 nanocomposites were synthesized and characterized. The release kinetics were also investigated. Antitumoral activity was evaluated on three cancer cell lines (HeLa, MDA-MB-231 and HCT116) and the effects on cell cycle arrest in HCT116 cells were evaluated. Finally, molecular dynamics simulations were performed of the complexes between Si113 or Si306 and the active site of both CDK 1 and 2., The work was financially supported by the University of Palermo. The work was carried out in the frame of the PON “AIM: Attrazione e Mobilità Internazionale” No. 1808223 project. SS and GG wish to acknowledge the AIRC project 2019 code 23725. The authors would thank Dr. Susanna Guernelli (University of Bologna) for TEM and SEM measurements.

In this paper the innovative approach of Nano into micro (NiM9 was developed to produce Nanoparticles loaded Ivacaftor to incorporate into mannitol or mannitol/cysteamine micromatrices for drug pulmonary administration in CF. Nanoparticles composed by a mixture of two polyhydrohydroxyethtylaspartamide copolymers containing a loading of Ivacaftor of 15.5 % w/w were produced. These Nanoparticles were incorporated into microparticles to obtain NiM that were characterized in terms of size and size distribution, interaction with CF-AM by rheological and turbidimetric studies as well as by aerodynamic diameter measurements. Finally the activity of Ivacaftor into these NiM was evaluated by in vitro preliminary experiments. NiM at matrix composed by a mixture of mannitol:cysteamine showed greater ability to reduce CF-AM viscosity whereas that based on just mannitol showed the better aerodynamic properties with a FRF of about 25 %. All produced NiM showed very good cytocompatibility and released Ivacaftor showed to be able to restore the chroride transport in vitro.

Cystic fibrosis (CF) patients develop a severe form of the disease when the cystic fibrosis transmembrane conductance regulator (CFTR) gene is affected by nonsense mutations. Nonsense mutations are responsible for the presence of a premature termination codon (PTC) in the mRNA, creating a lack of functional protein. In this context, translational readthrough-inducing drugs (TRIDs) represent a promising approach to correct the basic defect caused by PTCs. By using computational optimization and biological screening, we identified three new small molecules showing high readthrough activity. The activity of these compounds has been verified by evaluating CFTR expression and functionality after treatment with the selected molecules in cells expressing nonsense&ndash, CFTR&ndash, mRNA. Additionally, the channel functionality was measured by the halide sensitive yellow fluorescent protein (YFP) quenching assay. All three of the new TRIDs displayed high readthrough activity and low toxicity and can be considered for further evaluation as a therapeutic approach toward the second major cause of CF.

P14ARF is a tumor suppressor encoded by the CDKN2a locus that is frequently inactivated in human tumors. P14ARF protein quenches oncogene stimuli by inhibiting cell cycle progression and inducing apoptosis. P14ARF functions can be played through interactions with several proteins. However, the majority of its activities are notoriously mediated by the p53 protein. Interestingly, recent studies suggest a new role of p14ARF in the maintenance of chromosome stability. Here, we deepened this new facet of p14ARF which we believe is relevant to its tumor suppressive role in the cell. To this aim, we generated a monoclonal HCT116 cell line expressing the p14ARF cDNA cloned in the piggyback vector and then induced aneuploidy by treating HCT116 cells with the CENP-E inhibitor GSK923295. P14ARF ectopic re-expression restored the near-diploid phenotype of HCT116 cells, confirming that p14ARF counteracts aneuploid cell generation/proliferation.

Aquatic plants in rivers interact with flow and exert an important role in maintaining suitable habitat and ecological equilibrium. Understanding turbulence structure in the presence of vegetation is important with respect to environmental processes, such as sediment transport and mixing of transported quantities. Literature indicates that mass and momentum exchanges in the presence of vegetation are strongly influenced by the sequence of coherent structures which form between vegetated and non-vegetated zones. In the present paper we investigate turbulence structure and coherent motion in high-curvature channels with submerged vegetation. The analysis is performed with the aid of detailed experimental data collected in a meandering flume of large amplitude. Results essentially highlight that the contribution of turbulence to lateral diffusion and to streamwise and vertical transport may be significantly influenced by the relative submergence h/kv. The dominant mechanism of exchange obtained for h/kv2. Quadrant analysis has been also applied to investigate the occurrence of turbulent events and the associated exchange mechanism. In particular, at the apex section, it has been found that ejection events dominate in the outer bank region and, as literature indicates, this could cause the suspension of sediment in the flow that is transported downstream. In the central region the motion is especially characterized by high-speed fluid directed towards the bed, influencing the transport process significantly.

This paper proposes a rapid and analytical approach to evaluate the steady-state eddy-current losses in hairpin wound induction motors fed by pulse width modulated inverter. The method is based on a custom frequency-dependent lumped parameter circuit, useful to evaluate the steady-state harmonic content of the phase current considering the modulation. Furthermore, simplifying hypotheses, suitably described and justified, allow the definition of an analytical model for the calculation of the Joule losses contribution for each harmonic considering the effect of eddy-currents. This proposed approach is compared with the computationally more expensive transient finite element method and applied, as test-case, to a 200kW induction motor designed for an electric vehicle. A realistic estimation of the method accuracy and computational time is provided in a practical case, as well as a quantitative evaluation of the eddy current losses due to the modulation.

This paper presents a preliminary sizing procedure for a fluid shaped rotor of a Synchronous Reluctance motor and the design refinement by an optimization step. Starting from the definition of the fluid shaped barrier based on the Joukosky equation and on the analogy between the magnetic and mechanical equations, the preliminary design can be defined. The method uses the same approach of the other rotor shapes accurately changed to match the features of the fluid shaped rotor. This procedure is applied to a case study where the stator core is already defined. After the definition of the preliminary design a further optimization is carried out which involves an optimization algorithm linked to the Finite Element analysis. The preliminary and the optimized designs are then compared and discussed.