1,721,205 research outputs found
Sviluppo locale, dinamiche globali e ruolo dell'operatore pubblico: un modello ecologico
No full textIn questo lavoro vengono analizzati gli effetti della variabilità macroeconomica sulle strategie di sviluppo regionale. Viene costruita una tassonomia delle politiche regionali e si procede ad un'analisi emirica su alcune regioni italiane per rilevare l'efficacia delle politiche di sviluppo adottate nell'ultimod ecennio in rapporto alla variaiblità dei contesti macroeconomici
Does Space Matter for Labour Markets and How? A Critical Survey of the Recent Italian Empirical Evidence
No full textThe aim of the chapter is accordingly to disentangle the relationship between
firms’ location decisions and labour market functioning, the purpose being to
evaluate how spatial variables affect the expected impact of labour policies
GM1-MEDIATED NEURODIFFERENTIATION IS PROMOTED BY OLIGOGM1-TRKA INTERACTION
Full text linkThe present study proposes a clarification on the molecular mechanism by which ganglioside GM1 promotes neurodifferentiation, demonstrating in vitro that neurotrophic functions are exerted by an interaction between the oligosaccharide portion (OligoGM1) and an extracellular domain of TrkA receptor.
Similarly to the entire molecule, the oligosaccharide portion of ganglioside GM1, rather than ceramide, is responsible for neurodifferentiation by augmenting neurite elongation and by increasing the expression of neurofilament proteins in mouse neuroblastoma cell line Neuro2a (N2a).
Conversely, the single components of OligoGM1 (asialo-OligoGM1, OligoGM2, OligoGM3, sialic acid or galactose) are not able to induce a neuro-like morphology. The neurodifferentiative effect is exerted instead by fucosyl-OligoGM1.
Contrarily to GM1, exogenous OligoGM1 never integrates in the plasma membrane composition and does not belong to the intracellular metabolism: the unique interaction with N2a is characterized by a weak non-covalent association to the plasma membrane that suggests the existence of an OligoGM1-stimulated target on the cell surface.
In fact, the neurotrophic properties of GM1 oligosaccharide are exerted by activating TrkA receptor and the following cascade leading to neurodifferentiation event.
The second part of this study elucidates the interaction between GM1 and TrkA, revealing a direct association of OligoGM1 to an extracellular domain of the receptor.
Photolabeling experiments, performed employing nitrogen azide radiolabeled GM1 derivatives, show a direct association of the oligosaccharide chain to TrkA.
Moreover, a bioinformatics study reveals that OligoGM1 fits perfectly in a pocket of the TrkA-NGF complex, stabilizing and favoring their intermolecular interactions as revealed by the increase in energy associated to the new complex TrkA-NGF-OligoGM1. A precise molecular recognition process between OligoGM1 and a specific extracellular domain of the TrkA receptor is supposed. According to the weak association of OligoGM1 to the cell surface, no covalent bounds between OligoGM1 and TrkA-NGF complex were found.
For the first time the molecular mechanism by which GM1 exerts its neurodifferentiative potential was identified, finding out a direct interaction between the oligosaccharide portion and an extracellular domain of TrkA receptor responsible for enhancing the signal transduction related to the neurodifferentiation pathway
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Multiscale approximation with hierarchical radial basis functions networks
No full textAn approximating neural model, called hierarchical radial basis function (HRBF) network, is presented here. This is a self-organizing (by growing) multiscale version of a radial basis function (RBF) network. It is constituted of hierarchical layers, each containing a Gaussian grid at a decreasing scale. The grids are not completely filled, but units are inserted only where the local error is over threshold. This guarantees a uniform residual error and the allocation of more units with smaller scales where the data contain higher frequencies. Only local operations, which do not require any iteration on the data, are required; this allows to construct the network in quasi-real time. Through harmonic analysis, it is demonstrated that, although a HRBF cannot be reduced to a traditional wavelet-based multiresolution analysis (MRA), it does employ Riesz bases and enjoys symptotic approximation properties for a very large class of functions. HRBF networks have been extensively applied to the reconstruction of three-dimensional (3-D) models from noisy range data. The results illustrate their power in denoising the original data, obtaining an effective multiscale reconstruction of better quality than that obtained by MRA
Treatment strategies for complex fractures of the tibial plateau with external circular fixation and limited internal fixation
No full textBACKGROUND: We intended to evaluate the technique of treatment of complex fractures of the tibial plateau using external circular fixation combined with limited internal fixation, and to evaluate the treatment outcomes. METHODS: From 1992 to 2002, we treated 59 patients (40 men, 19 women) ranging in age from 23 to 63 years with the external circular fixation. All the cases were classified preoperatively as Schatzker types V, VI/Orthopedic Trauma Association 41-C1.3, C2.3, C3.1, C3.3. Five fractures were open. Three different strategies of treatment were used: (1) the frame is confined to the tibia when the external fixation is stable enough to allow knee bending; (2) the frame is extended onto the distal femur, with the proximal tibial ring located at the level of the tibial plateau when the joint surface is severely unstable; and (3) the frame is extended onto the distal femur, with the proximal tibial ring located more distally, bypassing the fracture, when the skin and soft tissue are compromised and within the fracture there is no bone suitable to place wires and pins for the external fixation construct. RESULTS: The results were evaluated as excellent in 30 patients (50.85%), good in 27 patients (45.76%), fair in 1 patient (1.695%), and poor in another 1 (1.695%). The patients' satisfaction was significantly related with the functional results. CONCLUSIONS: Our hybrid Ilizarov method combined with minimal internal fixation enables excellent to good results in most cases of complex tibial plateau fractures
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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