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En 2020, el informe sobre la salud dental en el mundo de la Organización Mundial de la Salud afirma que la caries dental sigue siendo un importante problema de salud bucodental y que existen considerables desigualdades en los programas de prevención entre países. La caries es una enfermedad infecciosa y crónica que implica la interacción de varios factores de riesgo biológicos, individuales y sociales. Cualquier estrategia de control de la caries debe tener en cuenta el contexto social y médico y basarse en la eliminación de los factores de riesgo. La evaluación del riesgo de caries de un paciente se basa en la identificación de los factores de riesgo, pero también de los factores de protección. Esto permite adaptar las estrategias preventivas y terapéuticas a la persona. Paralelamente, se pueden desarrollar estrategias preventivas a escala de la población. Los programas colectivos se dirigen al conjunto de la población o a las poblaciones objetivo. Lo más apropiado parece ser un enfoque ecológico, que tenga en cuenta el sistema en su conjunto, los factores individuales y sociales, y que integre un enfoque de riesgo común con otras enfermedades crónicas. Así, los modelos de intervención podrían basarse en un fundamento básico y universal e incluir un enfoque «medicalizado» para las poblaciones más expuestas a la enfermedad, que se consideraría en el marco de los programas de educación terapéutica de los pacientes.

The palladacycle {Pd[k¹-C, k¹-N-C&dbd;(C6H5)C(Cl)CH2NMe2](μ-Cl)}2 1 derived from the chloropalladation of 3-(dimethylamino)-1-phenyl-1-propyne promotes the arylation of olefins under relatively mild reaction conditions. The coupling of iodoarenes and activated bromoarenes with n-butylacrylate and styrene occurs at room temperature. Turnover numbers of up to 85 000 have been achieved with deactivated bromoarenes and up to 1000 for activated chloroarenes at higher temperatures (80−150 °C).

31 consecutive, surgically verified cases of tumors growing from the middle into the posterior fossa or viceversa are reviewed. The results of plain X-ray studies, of angiography and computed tomography (CT)are described. Comparative analysis of the various studies was decisive for predicting the nature of the lesion in the majority of the cases.

Galvanomagnetic and optical data are presented for stage 1, 2 and 3 alkali-metal intercalation compounds. Relative to pure graphite, conductivity is enhanced, mobility is reduced and the reflection spectrum becomes metallic. Analysis of the data demonstrates two-carrier behavior for the stage 1 and 2 compounds; these materials appear to be semi-metals with comparable densities of electrons and holes, rather than simplen-type metals as previously assumed.

Sustainable development issues have become very important in the recent years, and the increased sensibility on sustainability of civil engineering structures are inducing to set the attention in recycling operations, also in the context of building materials. Concrete is the most used construction material in the world and its production requires a considerable demand of energy and raw materials, inducing significant gases emissions and huge quantity of natural materials and non-renewable resources exploitation. Electric Arc Furnace Concrete (EAF concrete) is a kind of recycled concrete in which its aggregates are the by-product of steel and iron producing processes, the so called Electric Arc Furnace (EAF) slag: while its environmental positive effect is easily understandable and intuitive, its effective usefulness and reliability in the building field is more difficult to accept. From the literature data, it seems that EAF concrete presents higher values of compressive and tensile strengths and modulus of elasticity than the natural concrete ones, and this might induces one to think that a higher structural reliability could be expected. However, it is worth recalling that this material is characterized by also a higher self-weight, thus, increasing the dead-load values. Hence, in this study, a reliability-based analysis of the structural load-carrying capacity of EAF reinforced concrete (RC) elements is carried out, through a fully probabilistic approach based on Monte Carlo simulations improved by Latin Hypercube method (LHS). The analysed RC elements are designed according to the Italian current construction code, and then, considering all the uncertainties included in the random variables definition, failure probability and relative reliability index are estimated and compared to the reliability of the same RC elements with natural concrete. Results indicate that, for the analysed cases, when EAF slag is used as coarse recycled aggregate, it is possible to guarantee the same reliability level than in RC elements realised with natural concrete.