Quantitative Evaluation by Glucose Diffusion of Microleakage in Aged Calcium Silicate-Based Open-Sandwich Restorations

This study compared the in vitro marginal integrity of open-sandwich restorations based on aged calcium silicate cement versus resin-modified glass ionomer cement. Class II cavities were prepared on 30 extracted human third molars. These teeth were randomly assigned to two groups (n = 10) to compare a new hydraulic calcium silicate cement designed for restorative dentistry (Biodentine, Septodont, Saint Maur des Fossés, France) with a resin-modified glass ionomer cement (Ionolux, Voco, Cuxhaven, Germany) in open-sandwich restorations covered with a light-cured composite. Positive (n = 5) and negative (n = 5) controls were included. The teeth simultaneously underwent thermocycling and mechanocycling using a fatigue cycling machine (1,440 cycles, 5–55°C; 86,400 cycles, 50 N/cm2). The specimens were then stored in phosphate-buffered saline to simulate aging. After 1 year, the teeth were submitted to glucose diffusion, and the resulting data were analyzed with a nonparametric Mann-Whitney test. The Biodentine group and the Ionolux group presented glucose concentrations of 0.074 ± 0.035 g/L and 0.080 ± 0.032 g/L, respectively. No statistically significant differences were detected between the two groups. Therefore, the calcium silicate-based material performs as well as the resin-modified glass ionomer cement in open-sandwich restorations

The role of environmental perceptions in migration decision-making: evidence from both migrants and non-migrants in five developing countries

© 2016, Springer Science+Business Media New York. Research has demonstrated that, in a variety of settings, environmental factors influence migration. Yet much of the existing work examines objective indicators of environmental conditions as opposed to the environmental perceptions of potential migrants. This paper examines migration decision-making and individual perceptions of different types of environmental change (sudden vs. gradual environmental events) with a focus on five developing countries: Vietnam, Cambodia, Uganda, Nicaragua, and Peru. The survey data include both migrants and non-migrants, with the results suggesting that individual perceptions of long-term (gradual) environmental events, such as droughts, lower the likelihood of internal migration. However, sudden-onset events, such as floods, increase movement. These findings substantially improve our understanding of perceptions as related to internal migration and also suggest that a more differentiated perspective is needed on environmental migration as a form of adaptation

Environmental changes and violent conflict

This letter reviews the scientific literature on whether and how environmental changes affect the risk of violent conflict. The available evidence from qualitative case studies indicates that environmental stress can contribute to violent conflict in some specific cases. Results from quantitative large-N studies, however, strongly suggest that we should be careful in drawing general conclusions. Those large-N studies that we regard as the most sophisticated ones obtain results that are not robust to alternative model specifications and, thus, have been debated. This suggests that environmental changes may, under specific circumstances, increase the risk of violent conflict, but not necessarily in a systematic way and unconditionally. Hence there is, to date, no scientific consensus on the impact of environmental changes on violent conflict. This letter also highlights the most important challenges for further research on the subject. One of the key issues is that the effects of environmental changes on violent conflict are likely to be contingent on a set of economic and political conditions that determine adaptation capacity. In the authors' view, the most important indirect effects are likely to lead from environmental changes via economic performance and migration to violent conflict. © 2012 IOP Publishing Ltd

Effective-Range Expansion of the Neutron-Deuteron Scattering Studied by a Quark-Model Nonlocal Gaussian Potential

The S-wave effective range parameters of the neutron-deuteron (nd) scattering are derived in the Faddeev formalism, using a nonlocal Gaussian potential based on the quark-model baryon-baryon interaction fss2. The spin-doublet low-energy eigenphase shift is sufficiently attractive to reproduce predictions by the AV18 plus Urbana three-nucleon force, yielding the observed value of the doublet scattering length and the correct differential cross sections below the deuteron breakup threshold. This conclusion is consistent with the previous result for the triton binding energy, which is nearly reproduced by fss2 without reinforcing it with the three-nucleon force.Comment: 21 pages, 6 figures and 6 tables, submitted to Prog. Theor. Phy

Evaluation of shear bond strength of two resin-based composites and glass ionomer cement to pure tricalcium silicate-based cement (Biodentine®)

Objectives: Tricalcium silicate is the major constituent phase in mineral trioxide aggregate (MTA). It is thus postulated that pure tricalcium silicate can replace the Portland cement component of MTA. The aim of this study was to evaluate bond strength of methacrylate-based (MB) composites, silorane-based (SB) composites, and glass ionomer cement (GIC) to Biodentine® and mineral trioxide aggregate (MTA). Material and Methods: Acrylic blocks (n=90, 2 mm high, 5 mm diameter central hole) were prepared. In 45 of the samples, the holes were fully filled with Biodentine® and in the other 45 samples, the holes were fully filled with MTA. The Biodentine® and the MTA samples were randomly divided into 3 subgroups of 15 specimens each: Group-1: MB composite; Group-2: SB composite; and Group-3: GIC. For the shear bond strength (SBS) test, each block was secured in a universal testing machine. Results: The highest (17.7±6.2 MPa) and the lowest (5.8±3.2 MPa) bond strength values were recorded for the MB composite-Biodentine® and the GIC-MTA, respectively. Although the MB composite showed significantly higher bond strength to Biodentine (17.7±6.2) than it did to MTA (8.9±5.7) (p<0.001), the SB composite (SB and MTA=7.4±3.3; SB and Biodentine®=8.0±3,6) and GIC (GIC and MTA=5.8±3.2; GIC and Biodentine=6.7±2.6) showed similar bond strength performance with MTA compared with Biodentine (p=0.73 and p=0.38, respectively). Conclusions: The new pure tricalcium-based pulp capping, repair, and endodontic material showed higher shear bond scores compared to MTA when used with the MB composite

Droit du service public

Doté d\u27une valeur analogue dans tous les États démocratiques, le service public (public utility, servicio público, Öffentlicher Versorgungsbetrieb, servizio pubblico), qui se distingue des concepts de droit européen (service d\u27intérêt général, service d\u27intérêt économique général, valeurs communes de l\u27Union), est une notion constante et unitaire des systèmes politiques et juridiques et fonde leur évolution au début du XXI siècle. Les acquis de la notion de service public n\u27ont pas été remis en question depuis la Libération. Les politiques publiques face à la mondialisation économique ne freinent pas sa vitalité, même si elles induisent une contractualisation des modes de gestion, des remaniements profonds de compétences des collectivités décentralisées et une diversification des principes juridiques structurant le service public. Les contraintes nées de l\u27internationalisation des échanges et des politiques de l\u27Union européenne n\u27ont modifié ni la validité de l\u27idée originelle de service public, ni son efficacité opératoire, ni sa fonction préservatrice du lien social. La quatrième édition de cet ouvrage intègre les modifications du droit du service public induites par le programme de modernisation de l\u27action publique depuis 2012. Le droit du service public concerne les pouvoirs publics, les administrations, les collectivités territoriales, les organes stratégiques des entreprises publiques ou privées et les juridictions. Il s\u27adresse tout autant aux administrateurs, aux avocats, aux citoyens, aux usagers des services publics, qu\u27aux étudiants en sciences sociales (droit, science politique, sociologie, histoire), de la licence au doctorat

Le harcèlement; De la société solidaire à la société solitaire

Contributions de :Joel Briman (Université Fédérale de Rio de Janeiro), Teresa Carreitero (Université de Rio de Janeiro), Guy Elcheroth (Université de Lausanne), Eugène Enriquez (Université de Paris VII), Nelly Ferreira (Université de Cergy-Pontoise), Vincent de Gaulejac (Laboratoire de Changement Social, Paris); Nicolas Guillet (Université de Cergy-Pontoise); Claudine Haroche (CNRS, Paris); Geneviève Koubi (Université de Cergy-Pontoise), Dominique Lhuilier (Université de Paris VII); Marc Maesschalck (Université de Louvain-la-Neuve); Alberto Puppo (Université de Cergy-Pontoise); Margarita Sanchez-Mazas (Université Libre de Bruxelles) ;Virginie Vrancx (Université Libre de Bruxelles)info:eu-repo/semantics/publishe