A thermodynamically consistent derivation of a frictional-damage cohesive-zone model with different mode i and mode II fracture energies

The present paper deals with the derivation of an interface model characterized by macroscopic fracture energies which are different in modes I and II, the macroscopic fracture energy being the total energy dissipated per unit of fracture area. It is first shown that thermo-dynamical consistency for a model governed by a single damage variable, combined with the choice of employing an equivalent relative displacement and of a linear softening in the stress-relative displacement law, leads to the coincidence of fracture energies in modes I and II. To retrieve the experimental evidence of a greater fracture energy in mode II, a micro-structured geometry is considered at the typical point of the interface where a Representative Interface Element (RIE) characterized by a periodic arrangement of distinct inclined planes is introduced. The interaction within each of these surfaces is governed by a coupled damage-friction law. A sensitivity analysis of the correlation between micromechanical parameters and the numerically computed single-point microstructural response in mode II is reported. An assessment of the capability of the model in predicting different mixed mode fracture energies is carried out both at the single microstructural interface point level and with a structural example. For the latter a double cantilever beam with uneven bending moments has been analyzed and numerical results are compared with experimental data reported in the literature for different values of mode mixity. © 2014 Elsevier Masson SAS. All rights reserved

Bond-slip analysis via a cohesive-zone model simulating damage, friction and interlocking

A recently proposed cohesive-zone model which effectively combines damage, friction and mechanical interlocking has been revisited and further validated by numerically simulating the pull-out test, from a concrete block, of a ribbed steel bar in the post-yield deformation range. The simulated response is in good agreement with experimental measurements of the bond slip characteristics in the post-yield range of deformed bars reported in the literature. This study highlights the main features of the model: with physically justified and relatively simple arguments, and within the sound framework of thermodynamics with internal variables, the model effectively separates the three main sources of energy dissipation, i.e. loss of adhesion, friction along flat interfaces and mechanical interlocking. This study provides further evidence that the proposed approach allows easier and physically clearer procedures for the determination of the model parameters of such three elementary mechanical behaviours, and makes possible their interpretation and measurement as separate material property, as a viable alternative to lumping these parameters into single values of the fracture energy. In particular, the proposed approach allows to consider a single value of the adhesion energy for modes I and II

Leader as Policy Device: The Hybridization of Head Teachers in Italy

The aim of this article is to show how educational policies in Italy in the last 15 years have conceived headship as a «lever of change», producing a sort of «subjection» which implies a remarkable hybridization of the role. The ongoing pressures on policymaking by «noneducational» actors are depicted as a feature of the Italian policies on the restructuring of school governance and headship. The topics presented are based on researches carried out in recent years and focusing on the training, selection and evaluation of Italian head teachers. The article is structured as follows. Firstly, we present the theoretical framework based on the conceptual tools of discourse and governance. Secondly, we offer a brief outline on how head teachers were «formed» as educators before the 1997 Autonomy Reform. In the final section, some tensions that emerge during the discussions on headship are presented by analysing a particular set of «technologies» such as training, selection and evaluation that aim to «S-Objectivate» specific head teachers. The analysis will allow us to shed light on what we think of as an invisible and politically remarkable dilemma that is at stake here: «headship as a managerialist device to ‘control’ education policies»

Privatising education policy-making in Italy: New governance and the reculturing of a welfarist education state

Philanthropies and private foundations are increasingly acting as key nodes of the policy assemblages through which neoliberal and neomanagerialist policies are entering the field of education in Italy. In a country where public school 'ineffectiveness' and 'resistance to innovation' are taken for granted nowadays, policy philanthropists-entrepreneurs are attempting to lead the way in re-thinking education according to the new globalised economic imperatives. Starting from the ongoing 'evaluation turn' of the Italian education system, the article unravels the complexities of those processes of policy influence. The analysis addresses multiple foci: the emergence of new discourses of education reform and the networks of social interaction they are rooted in; the generative effects such discourses can have on producing new positions, subjectivities, opportunities; and the structural selectivities influencing education policy-making. The article highlights the first moves of a peculiar process of 'policy privatisation' whose main potential outcomes are both a process of education policy-making privatisation and a reculturing of education according to a new private-business ethos. Keywords: policy privatisation, philanthropy, education governance, neoliberalism, NPM, Italy (Published: 16 September 2013) Citation: Education Inquiry (EDUI) 2013, 4 , 22615, http://dx.doi.org/10.3402/edui.v4i3.2261

Phenotypic definition and genotype-phenotype correlates in pmpca-related disease

Background: Peptidase mitochondrial processing alpha (PMPCA) biallelic mutations cause a spectrum of disorders ranging from severe progressive multisystemic mitochondrial encephalopathy to a milder non-progressive cerebellar ataxia with or without intellectual disability. Recently, we and others described an intermediate phenotype in two unrelated patients. Methods: We report a second Italian patient carrying novel PMPCA variants (p.Trp278Leu; p.Arg362Gly). Molecular modeling, dynamics simulation, RT-qPCR, and Western blotting were performed to predict the pathogenic impact of variants in the two Italian patients and attempt genotype-phenotype correlates. Results: In line with the two patients with intermediate phenotypes, our case presented global psychomotor delay with regression, intellectual disability, spastic-ataxic gait, and hyperkinetic movements, with cerebellar atrophy and bilateral striatal hyperintensities. However, blood lactate, muscle biopsy, and MRI spectroscopy were normal. PMPCA protein levels were significantly higher than controls despite normal cDNA levels. Dynamics simulation of several PMPCA missense variants showed a variable impact on the flexibility of the glycine rich loop and, for some cases, on the overall protein stability, without clear genotype-phenotype correlates. Conclusion: We confirm the expansion of PMPCA phenotypic spectrum including an intermediate phenotype of progressive encephalopathy without systemic involvement. The association of cerebellar atrophy with “Leigh-like” striatal hyperintensities may represent a “red flag” for this condition

Educational reform and modernisation in Europe: The role of national contexts in mediating the new public management

This is the author accepted manuscript. The final version is available from SAGE Publications via the DOI in this recordThis article examines the spread of new public management (NPM) across European education systems as it has traversed national boundaries. While recognising the transnational dimensions of the spread of NPM, the authors offer new insights into the importance of national contexts in mediating this development in educational settings by focusing upon NPM within three European countries (England, Italy and Norway). We reveal its recontextualisation in these sites and the interplay between NPM, and local and national conditions. This analysis is underpinned by a theoretical framework that seeks to capture the relationship between education and the state and to reveal tensions produced by NPM both as a shaping force and an entity shaped by local conditions in these contexts. The article concludes by focusing upon the complexities and specificities of NPM recontextualisation in the three countries as a basis for a reflection upon possible future policy trajectories

SUFU haploinsufficiency causes a recognisable neurodevelopmental phenotype at the mild end of the Joubert syndrome spectrum.

Joubert syndrome (JS) is a recessively inherited ciliopathy characterised by congenital ocular motor apraxia (COMA), developmental delay (DD), intellectual disability, ataxia, multiorgan involvement, and a unique cerebellar and brainstem malformation. Over 40 JS-associated genes are known with a diagnostic yield of 60%-75%.In 2018, we reported homozygous hypomorphic missense variants of the SUFU gene in two families with mild JS. Recently, heterozygous truncating SUFU variants were identified in families with dominantly inherited COMA, occasionally associated with mild DD and subtle cerebellar anomalies. We reanalysed next generation sequencing (NGS) data in two cohorts comprising 1097 probands referred for genetic testing of JS genes. Heterozygous truncating and splice-site SUFU variants were detected in 22 patients from 17 families (1.5%) with strong male prevalence (86%), and in 8 asymptomatic parents. Patients presented with COMA, hypotonia, ataxia and mild DD, and only a third manifested intellectual disability of variable severity. Brain MRI showed consistent findings characterised by vermis hypoplasia, superior cerebellar dysplasia and subtle-to-mild abnormalities of the superior cerebellar peduncles. The same pattern was observed in two out of three tested asymptomatic parents. Heterozygous truncating or splice-site SUFU variants cause a novel neurodevelopmental syndrome encompassing COMA and mild JS, which likely represent overlapping entities. Variants can arise de novo or be inherited from a healthy parent, representing the first cause of JS with dominant inheritance and reduced penetrance. Awareness of this condition will increase the diagnostic yield of JS genetic testing, and allow appropriate counselling about prognosis, medical monitoring and recurrence risk

The chemical etching as a method for post-processing of 3D cellular structures obtained by electron-beam melting: limitations and difficulties

Chemical etching is a promising method for post-surface treatment and the removal of residual powder from implants obtained using electron beam cladding. Partially sintered powder particles that remained on the implants surface can be difficult to remove from the internal structure of the additively manufactured specimens. In order to remove residual powder from scaffolds' interior, an aqueous solution of HF and HNO3 acids was used. Multiple immersion was more effective to remove the remaining powder, which was explained from the chemical point of view. The influence of the chemical etching on mechanical properties, mechanical behavior, fracture modes, and morphology was investigated

the effects of climate change on the multifunctional role of basilicata s forests the effects induced on yield and co2 absorption

The first studies on the possible impact of climate change on European forests and the development of adaptation and mitigation strategies began in the 1990s and resulted in the identification of risk assessment models and forest management tools. The prediction of climate change impacts on forests has been based using the evidence theory or Dempster-Shafer (DS)'s theory, appropriately spatialised. The implemented evidence lines refer to the concepts of vulnerability and resilience. The results of the DS model, applied to the Basilicata region, were utilised to assess the loss in biomass production capacity and CO2 absorption ability of different forest-derived biomasses. The loss in stumpage value and in the estimated CO2 absorption shows a reduction over time of forest system's economic value that is basically higher in 2050 than in 2100. The applied methodological approach has shown that the high degree of spatial and information detail may be helpful to produce good predictions to envisage environmental policy strategies for the monitoring and mitigation of the damages caused by the climate change, with a view to ensuring the ecosystems' capacity to produce positive externalities, including air carbon sequestration capacity