Variaciones en el desarrollo, influencias socioculturales, y dificultades en el aprendizaje de las matemáticas

Es sabido que la mayoría de los niños entran en la escuela con conocimientos y recursos fundacionales para su aprendizaje matemático. Sin embargo, esta no es la historia completa. Resultados de investigaciones revelan enormes diferencias en los niveles de competencia matemática de los niños pequeños, y estas diferencias parecen ser más acusadas en los Estados Unidos que en algunos otros países (por ejemplo, China) (Starkey y Klein, 2008). En este artículo se describen los tipos de diferencias que se dan y se ofrece una revisión sobre lo que se sabe acerca de la naturaleza y las fuentes de las variaciones en el desarrollo entre los niños

Fundamentos cognitivos para la iniciación en el aprendizaje de las matemáticas

En este artículo, sobre fundamentos cognitivos para la iniciación en el aprendizaje de las matemáticas, se realiza una revisión de investigaciones sobre el aprendizaje de las matemáticas en educación infantil. Esta revisión está estructurada según los siguientes apartados: Evidencias sobre la comprensión temprana del número, desarrollo del pensamiento espacial y la geometría, desarrollo de la medición, y regulación de la conducta y la atención

Contenido matemático fundacional para el aprendizaje en los primeros años

En este capítulo se describe el contenido matemático fundacional accesible para niñas y niños pequeños. El foco en este capítulo está puesto en las propias ideas matemáticas, más que en la enseñanza y el aprendizaje de las mismas. Estas ideas matemáticas se dan por sentadas por los adultos, pero son sorprendentemente profundas y complejas. Hay dos áreas fundamentales en las matemáticas para la primera infancia: (1) el número y (2) la geometría y la medición, tal como identifican los Focos Currículares del NCTM y subrraya este comité. También hay importantes procesos de razonamiento matemático en que los niños deben implicarse. Este capítulo también describe algunas de las conexiones más importantes de las matemáticas infantiles con las matemáticas posteriores

Toward a multi-faceted conception of co-production of climate services

Increasing numbers of scholars and practitioners appeal to procedural theories of ‘co-production’ as they work to transform climate science into climate services. Most work in this direction theorises co-production as an ‘iterative and interactive’ process between climate service providers and users, with success measured mainly in terms of the usefulness and usability of the information product for the user. But notwithstanding these first important steps, this perspective paper argues that the current study of climate service co-production is too narrowly framed, and fails to properly engage with the broad and rich literature that conceives of co-production processes in a diversity of ways. The authors suggest a fresh look on co-production as a process best examined simultaneously from several complimentary perspectives, with reference to recent work reconceptualising co-production as an eight-sided ‘prism’. Using an illustrative example of climate services developed to predict and visualise future flooding in the municipality of Voss, in Norway, the paper demonstrates how this prism concept of co-production can enable a more comprehensive view on co-production as a multi-faceted phenomenon, improve mutual understanding among actors and, ultimately, help design climate services that are better tailored for climate change responses in particular contexts

Potentially toxic metals in historic landfill sites: Implications for grazing animals

Municipal waste disposal is an increasing global problem, frequently solved by the use of landfill sites. Following closure, such sites contain a legacy of pollutants and must be managed to provide a safe and useful end life. The soils and vegetation from four historic landfill sites were analysed to determine the extent of pollution by potentially toxic metals (PTMs). Data were subsequently assessed to determine if post closure uses involving grazing were safe for the animals. The heaviest and widest spread soil contamination was due to Ni. Concentrations at all sites exceeded the 95th percentile value for rural soils, in one case by a factor of 30. Cu and Pb contamination was identified at some sites, but no evidence of Al or Zn contamination was found. Oral bioaccessibility testing showed that the availability of Ni in soil was exceedingly low, whilst that of Cu and Pb was high. Concentrations in plant shoots differed significantly amongst the sites, but interspecific differences in shoot concentration were only significant in the case of Cu. The results indicated that exposure levels to grazers would be at or below tolerable levels, indicating that it is generally safe to graze historic landfill. However, animals could be exposed to higher levels of PTMs than would be expected from rural locations, and grazing under conditions where soil consumption may be high could result in levels of exposure to Al, Ni and Pb exceeding tolerable levels. © Springer International Publishing 2014

Chapter 20 Assessment of radiation pollution from nuclear power plants

Nuclear power plants split uranium atoms in a process called fission. In a nuclear power plant, heat is generated to produce steam that spins a turbine to generate electricity. Nuclear energy has been proposed in response to the need for a clean energy source compared to CO2 production plants. However, nuclear energy is not necessarily a source of clean energy as nuclear power plants release small amounts of greenhouse emissions in activities related to building and running the plant. Moreover, even if all safety measures are followed, there is no guarantee that an accident will not occur in a nuclear power plant. In the case of an accident involving a nuclear power plant, the environment and the people around it may be exposed to high levels of radiation. Another important environmental problem related to nuclear energy is the generation of radioactive waste that can remain radioactive and dangerous to human health for thousands of years. There are also several issues with burying the radioactive waste. Here, we describe different types of radioactive waste pollution from nuclear power plants, their environmental effects, nuclear regulations, and nuclear power plant incidents. Moreover, two case studies on nuclear power plant accidents and their consequences are discussed

Improving impact evaluations through randomised experiments : The challenge of the National Research Council report for European criminology

The National Research Council (NRC) report on Improving Evaluation of Anticrime Programs presents and discusses a wide array of techniques of evaluation. Although recognising the very high internal validity of randomised experiments, it considers, under certain conditions, quasi-experiments and observational studies as equally valid approaches. This conclusion is critically reviewed from a European perspective, where only a few randomised trials have been realised so far. It is argued that many critiques routinely addressed to randomised experiments, such as ethical concerns or low acceptance among practitioners, are either unfounded or can be adequately dealt with through imaginative adjustments. On the other hand, randomised controlled trials need to take the challenge of broadening the perspective, especially by looking at long-term effects that no other method can consider with comparable internal validity. Other recommendations include using innovative measures of re-offending, considering dynamic rather than static criteria of re-offending, and looking, beyond re-offending, at rehabilitation in other areas of life. Particular challenges are the possible placebo effects that evaluators in criminal justice have not yet found appropriate ways to deal with