"Real world" problems

We consider it important that pre-service teachers master both mathematical problem solving and the choice and analysis of problems, together with the way of posing them in the classroom, so that pupils’ thinking processes may be better stimulated. The teacher must make several decisions about the organisation of their own teaching: these relate to the choice and systematisation of ‘good’ problems, the management of pupils’ personal solutions in the sharing phases (discussion), the possible ways for making these personal solutions evolve towards expert solutions, which are the main goal. In this context, a priori analysis becomes one of the professional tools helping teachers to formulate their choices and decisions (Charnay, 2003). The “Real world” problems proposal sits within a set of activities that stimulate work with problems starting from a suitable a priori analysis, in order to identify the mathematical concepts at stake and to determine whether, how and with what aims they can be used in teaching

Richness, origin and structure of an Eimeria community in a population of Eastern cottontail

The composition and structure of a community of Eimeria was investigated in a population of Eastern cottontail (Sylvilagus floridanus) introduced into Italy. Eight Eimeria species were found, of which all but 1 had North American origins and were presumably introduced into Italy together with imported cottontails. The success of cottontails in spreading microparasites is probably related to their massive release for hunting purposes. Nearly all cottontails were infected with at least 1 Eimeria species, with bimonthly prevalence ranging from 0–6·3% (E. leporis) to 42·9–89·3% (E. environ). Bayesian model averaging and multivariate techniques were used to investigate the relationships between the occurrence of each parasite and the structure of the relative community. Among the host parameters, only sex was found to be associated with the prevalence of E. honessi, while the rest of the parameters were only weakly correlated with prevalence and species richness. This indicates that individual phenotypic host characteristics are probably less important than environmental factors in determining levels of parasite prevalence and diversity. The community of Eimeria species was probably structured by competition, with less species co-occurrence than expected under a null hypothesis. This was made evident by the low co-occurrence of E. environ and E. neoirresidua with E. poudrei, E. honessi, and E. maior

Natural infection with two genotypes of Cryptosporidium in red squirrel (Sciurus vulgaris).

We investigated the genotypes of Cryptosporidium infecting red squirrels (Sciurus vulgaris L.) in two areas of the Western Alps in Italy. Examination of 141 faecal samples from 70 red squirrels revealed oocysts of Cryptosporidium in 17 animals (24.3%). Based on 18S rRNA gene sequencing, two genotypes of Cryptosporidium species were found: 15 squirrels were positive for the Cryptosporidium ferret genotype and 2 for the Cryptosporidium chipmunk genotype I. The occurrence and intensity of Cryptosporidium infection did not differ between the study areas or sex. More than 85% of the positive animals were adults; however no difference was found between Cryptosporidium infection in the juvenile and adult age groups. Oocysts of the Cryptosporidium ferret genotype measured 5.5 \ub1 0.3 7 5.2 \ub1 0.2 \u3bcm (shape index 1.06) and the Cryptosporidium chipmunk genotype I 5.8 \ub1 0.3 7 5.4 \ub1 0.3 \u3bcm (shape index 1.07). Neonatal and adult CD1 and BABL/c mice inoculated with 1 7 103 fresh oocysts of both genotypes did not produce detectable infection

A world of information at their fingertips: College students\u27 motivations and practices in their self-determined information seeking

People frequently engage in the process of “heutagogy” (i.e., self-determined learning). Unlike pedagogy and andragogy, heutagogy occurs without a structure or leader setting the context and directing the learning toward a specific goal. The lack of structure and the possible self-determination of topic, value, source, and trust in information led us to wonder about the motivations, goals, and processes considered by college students as they engage in self-determined learning. We conducted a survey with 83 American college students regarding their information-seeking preferences and behaviors. Some students reported accessing different media depending on what information they were seeking, while others sought multiple forms of information from the same media. Family and community influenced their trust in media, yet they also recognized experts and data as important justifications for credibility of media. We exposed some relationships among personal characteristics, perceptions of information, and self-determined learning activities. We conclude with implications and directions for future research