1,242 research outputs found

    Materiale didattico vario

    Get PDF

    Inauguration of the Centro 3R for the promotion of 3Rs principles in teaching and research

    Get PDF
    The first European interuniversity center dedicated to promoting 3Rs principles in teaching and research was inaugurated in Pisa, Italy on March 14, 2018. The Centro 3R1 was spearheaded by the Universities of Pisa and Genova. Membership is open to all Italian universities and agreements for twinning across Europe and other countries are being pursued

    A supervisory sliding mode control approach for cooperative robotic system of systems

    Get PDF
    This paper deals with the formulation of a supervisory sliding mode (SM) control approach oriented to deal with the interesting class of system of systems of robotic nature. This class of systems is characterized by the fact of being inherently distributed, cooperative, and, possibly, heterogeneous. In this paper, we propose a modular and composable approach relying on basic modules featuring a multilevel functional architecture, including a supervisor and a couple of hybrid position/force control schemes associated with a couple of cooperative robotic manipulators. In principle, the overall robotic system we are referring to can be viewed as a collection of basic modules of that type. In this paper, we focus on the design of the basic module. The hybrid position/force control schemes therein included are based on position and force controllers. The proposed position and force controllers are of SM type, to assure suitable robustness to perform a satisfactory trajectory tracking even in presence of unavoidable modeling uncertainties and external disturbances. The verification and the validation of our proposal have been performed by simulating the supervisor and the hybrid control scheme applied to one of the two robotic manipulators while experimentally testing the position control on the other arm. The experimental part of the tests has been carried out on a COMAU SMART3-S2 anthropomorphic industrial robotic manipulator

    Full vectorial BPM modeling of Index-Guiding Photonic Crystal Fibers and Couplers

    Get PDF
    A 3D full-vectorial Beam Propagation Method is successfully applied to compute both the propagation constants and the modal profiles in high-contrast silica-air index-guiding Photonic Crystal Fibers. The approach is intrinsically suited to investigate longitudinally varying structures or propagation and polarization effects, which are of practical interest for advanced optical applications. As an example we model a dual-core coupler, showing that efficient polarization preserving coupling can be expected

    Guided ion beam investigation of the reaction CO + + CO. C-O bond activation and C-C bond formation

    Get PDF
    Abstract We have investigated six different endothermic channels in the reaction of CO + ions with neutral CO. For each ionic product we have measured the kinetic energy dependence of the integral cross section and inferred the neutral products by the reaction energetics. The onset of the process producing C + , O, and CO, has been identified by a feature of the integral crosssection located at about 8.5 eV. Measurements of the product isotopic ratio suggest that C + originates from both the CO + ion and the neutral CO molecule. For the reaction channels producing C 2 + + O 2 and C 2 O + + O respectively, measurements of the reaction thresholds allow us to estimate the heats of formation of these two ionic products

    The chromosomal passenger complex controls the function of endosomal sorting complex required for transport-III Snf7 proteins during cytokinesis

    Get PDF
    Cytokinesis controls the proper segregation of nuclear and cytoplasmic materials at the end of cell division. The chromosomal passenger complex (CPC) has been proposed to monitor the final separation of the two daughter cells at the end of cytokinesis in order to prevent cell abscission in the presence of DNA at the cleavage site, but the precise molecular basis for this is unclear. Recent studies indicate that abscission could be mediated by the assembly of filaments comprising components of the endosomal sorting complex required for transport-III (ESCRT-III). Here, we show that the CPC subunit Borealin interacts directly with the Snf7 components of ESCRT-III in both Drosophila and human cells. Moreover, we find that the CPC's catalytic subunit, Aurora B kinase, phosphorylates one of the three human Snf7 paralogues—CHMP4C—in its C-terminal tail, a region known to regulate its ability to form polymers and associate with membranes. Phosphorylation at these sites appears essential for CHMP4C function because their mutation leads to cytokinesis defects. We propose that CPC controls abscission timing through inhibition of ESCRT-III Snf7 polymerization and membrane association using two concurrent mechanisms: interaction of its Borealin component with Snf7 proteins and phosphorylation of CHMP4C by Aurora B

    Cross-regulation between Aurora B and Citron kinase controls midbody architecture in cytokinesis.

    Get PDF
    Cytokinesis culminates in the final separation, or abscission, of the two daughter cells at the end of cell division. Abscission relies on an organelle, the midbody, which forms at the intercellular bridge and is composed of various proteins arranged in a precise stereotypic pattern. The molecular mechanisms controlling midbody organization and function, however, are obscure. Here we show that proper midbody architecture requires cross-regulation between two cell division kinases, Citron kinase (CIT-K) and Aurora B, the kinase component of the chromosomal passenger complex (CPC). CIT-K interacts directly with three CPC components and is required for proper midbody architecture and the orderly arrangement of midbody proteins, including the CPC. In addition, we show that CIT-K promotes Aurora B activity through phosphorylation of the INCENP CPC subunit at the TSS motif. In turn, Aurora B controls CIT-K localization and association with its central spindle partners through phosphorylation of CIT-K's coiled coil domain. Our results identify, for the first time, a cross-regulatory mechanism between two kinases during cytokinesis, which is crucial for establishing the stereotyped organization of midbody proteins.C.M. holds a Cambridge Cancer Centre PhD studentship, which is supported by Cancer Research UK and the MRC. Z.I.B. was supported by a Gwynaeth Pretty PhD studentship and the BlueGnome Molecular Genetics Fund from the Department of Pathology, University of Cambridge, and was also a recipient of a short-term EMBO fellowship and a fellowship from the Cambridge Philosophical Society. G.C. and M.G. are supported by a grant ‘Progetto di Ricerca di Interesse Nazionale’ (PRIN 2012) from the Ministero dell'Istruzione, Università e Ricerca. P.P.D. is the recipient of the Maplethorpe Fellowship from Murray Edwards College, Cambridge, UK.This is the final version of the article. It first appeared from Royal Society Publishing via https://doi.org/10.1098/rsob.16001

    Prospective randomised pilot study of management of the pancreatic stump following distal resection

    Get PDF
    Background Numerous surgical techniques have been described in the literature for pancreatic stump management following left resection, but there is only one prospective, randomised study. A prospective randomised pilot study was designed to assess five different pancreatic stump management techniques after distal resection in an attempt to identify which was the most effective in terms of complications and ease of execution. Methods Sixty-nine consecutive patients were randomly assigned to five different treatment groups: manual suturing, suturing plus fibrin glue, suturing plus polypropylene mesh, pancreaticojejunostomy and suturing with a stapler. All presented a soft residual pancreas. Results The overall incidence of pancreatic fistula was 19%, ranging from 7% to 33% in the different treatment groups. None of the techniques Significantly reduced the incidence of postoperative complications. Discussion On weighing the complications observed against ease and speed of execution, the construction of a pancreaticojejunostomy and closure of the stump with a mechanical stapler may be regarded as the procedures to be tested in future

    Experimental bounds on collapse models from gravitational wave detectors

    Get PDF
    Wave function collapse models postulate a fundamental breakdown of the quantum superposition principle at the macroscale. Therefore, experimental tests of collapse models are also fundamental tests of quantum mechanics. Here, we compute the upper bounds on the collapse parameters, which can be inferred by the gravitational wave detectors LIGO, LISA Pathfinder, and AURIGA. We consider the most widely used collapse model, the continuous spontaneous localization (CSL) model. We show that these experiments exclude a huge portion of the CSL parameter space, the strongest bound being set by the recently launched space mission LISA Pathfinder. We also rule out a proposal for quantum-gravity-induced decoherence

    Non-Intubated Thoracic Surgery: Standpoints and Perspectives

    Get PDF
    Non-intubated video-assisted thoracic surgery (NI-VATS) combines the advantages of a non-intubated surgery with the benefits of a minimally invasive approach. First, NI-VATS is performed in the case of fragile patients when general anesthesia and/or orotracheal intubation can be foreseen as inconvenient. However, NI-VATS indications have been increasingly extended to different patient conditions, considering the increasingly assessed safety and feasibility of the procedure. Currently, the NI-VATS approach is used worldwide for different thoracic surgery procedures, including the management of malignant pleural effusion, surgical treatment of empyema, anatomical and non-anatomical lung resection, and other indications. In fact, this approach has shown to be less impactful than VATS under general anesthesia, allowing for shortened hospitalization and faster recovery after surgery. Besides, NI-VATS is associated with fewer pulmonary complications, less respiratory distress, and a mild systemic inflammatory reaction. For these reasons, this approach should be considered not only in patients with poor cardiac or respiratory function (general functional reserve), but also in other eligible conditions. We explored the anesthetic and surgical aspects of such an approach, including the management of analgesia, cough reflex, depth of sedation, and intraoperative technical issues to put this approach in perspective
    • …
    corecore