Gli alunni stranieri e l’apprendimento delle matematica: alcune riflessioni sul caso italiano

The growing presence of foreign students in the Italian school continually interrogate teachers, policy makers and all those who are daily faced with issues related to this more and more structural reality. This work presents an analysis of the educational achievements in Mathematics of foreign students who have just completed the first cycle of education (5th grade) in Italy. To this end, we use INVALSI data that have the advantage to measure learning outcomesthrough standardized tests. Studying the frequency of responding correctly to any individual item and controlling for students’ background, we find substantially different and more encouraging reading of the learning gaps between Italian and foreign students.La crescente presenza di allievi stranieri nella scuola italiana interroga continuamente gli insegnanti, i decisori politici e tutti coloro che si trovano quotidianamente a fronteggiare le problematiche legate a questa realtà sempre più strutturale. Il presente contributo propone un’analisi sugli esiti in Matematicaalle Rilevazioni INVALSI 2014 degli studenti con cittadinanza non italiana che hanno appena terminato il primo ciclo di istruzione (classe V della scuola primaria). Considerando la probabilità di rispondere correttamente ai singoli item e tenendo sotto controllo alcune condizioni di contesto, si può avere una lettura diversa e più incoraggiante dei divari nell’apprendimento tra alunni italiani e stranieri

Having Children in Europe: The Role of Social Capital

We explore the role of social capital in explaining reproductive behaviour and its differences among the European countries. We adopt a comprehensive concept of social capital that combines several elementary indicators and estimate its impact on the probability of having a first or a further child among reproductive-age women currently in a partnership union. We cluster countries in four groups and discuss the results in terms of different welfare state regimes. Data come from the 2014 EU Statistics on Income and Living Conditions survey (N=15,735) which we analysed through a generalized ordered logit model. Our findings support the hypothesis that women who can count on higher level of social capital show higher chance to give birth to a baby and this holds both for each country group and for Europe as a whole. By showing the importance of operationalize a complex and multivariate definition of social capital we contributed to the debate about its relationship with individual reproductive behaviour

Genetic Determinants of Human Longevity

In the last two decades, due to the continuous increase of lifespans in Westernsocieties, and the consequent growing of the elderly population, have witnessedan increase in the number of studies on biological and molecular factors able topromote healthy aging and reach longevity. The study of the genetic componentof human longevity demonstrated that it accounts for 25% of intra populationphenotype variance. The efforts made to characterize the genetic determinantssuggested that the maintenance of cellular integrity, inflammation, oxidativestress response, DNA repair, as well as the use of nutrients, represent the mostimportant pathways correlated with a longer lifespan. However, although aplethora of variants were indicated to be associated with human longevity, onlyvery few were successfully replicated in different populations, probably becauseof population specificity, missing heritability as well as a complex interactionamong genetic factors with lifestyle and cultural factors, which modulate theindividual chance of living longer. Thus, many challenges remain to be addressedin the search for the genetic components of human longevity. This Special Issue isaimed to unify the progress in the analysis of the genetic determinants of humanlongevity, to take stock of the situation and point to future directions of the field.We invite submissions for reviews, research articles, short-communicationsdealing with genetic association studies in human longevity, including all types ofgenetic variation, as well as the characterization of longevity-related genes

Epidemiological, genetic and epigenetic aspects of the research on healthy ageing and longevity

Healthy ageing and longevity in humans result from a number of factors, including genetic background, favorable environmental and social factors and chance

Mathematics teaching and learning: a paper starting from Invalsi data

This paper illustrates the main teaching practices features in the Italian primary and secondary school, by using new data, provided by Invalsi, about teachers’ daily activities. We merge such information with the scores achieved by the students in the Invalsi test. Our study reframes the cognitive test results in mathematics from a new bottom-up perspective, that is internal to the educational system. La didattica della matematica e gli apprendimenti: un contributo a partire dai dati InvalsiLa finalità principale del presente lavoro è di illustrare alcune caratteristiche delle pratiche didattiche del primo e del secondo ciclo di istruzione, utilizzando alcuni nuovi dati forniti da Invalsi sulle attività quotidiane degli insegnanti. Unendo queste informazioni con i punteggi ottenuti dagli studenti nel test Invalsi, si vogliono approfondire i risultati ottenuti dagli studenti in matematica partendo da una nuova prospettiva, interna al sistema di educazione.

A novel similarity-measure for the analysis of genetic data in complex phenotypes

BACKGROUND: Recent technological advances in DNA sequencing and genotyping have led to the accumulation of a remarkable quantity of data on genetic polymorphisms. However, the development of new statistical and computational tools for effective processing of these data has not been equally as fast. In particular, Machine Learning literature is limited to relatively few papers which are focused on the development and application of data mining methods for the analysis of genetic variability. On the other hand, these papers apply to genetic data procedures which had been developed for a different kind of analysis and do not take into account the peculiarities of population genetics. The aim of our study was to define a new similarity measure, specifically conceived for measuring the similarity between the genetic profiles of two groups of subjects (i.e., cases and controls) taking into account that genetic profiles are usually distributed in a population group according to the Hardy Weinberg equilibrium. RESULTS: We set up a new kernel function consisting of a similarity measure between groups of subjects genotyped for numerous genetic loci. This measure weighs different genetic profiles according to the estimates of gene frequencies at Hardy-Weinberg equilibrium in the population. We named this function the "Hardy-Weinberg kernel". The effectiveness of the Hardy-Weinberg kernel was compared to the performance of the well established linear kernel. We found that the Hardy-Weinberg kernel significantly outperformed the linear kernel in a number of experiments where we used either simulated data or real data. CONCLUSION: The "Hardy-Weinberg kernel" reported here represents one of the first attempts at incorporating genetic knowledge into the definition of a kernel function designed for the analysis of genetic data. We show that the best performance of the "Hardy-Weinberg kernel" is observed when rare genotypes have different frequencies in cases and controls. The ability to capture the effect of rare genotypes on phenotypic traits might be a very important and useful feature, as most of the current statistical tools loose most of their statistical power when rare genotypes are involved in the susceptibility to the trait under study

Common polymorphisms in nitric oxide synthase (NOS) genes influence quality of aging and longevity in humans

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Mitochondrial DNA involvement in human longevity

AbstractThe main message of this review can be summarized as follows: aging and longevity, as complex traits having a significant genetic component, likely depend on a number of nuclear gene variants interacting with mtDNA variability both inherited and somatic. We reviewed the data available in the literature with particular attention to human longevity, and argued that what we hypothesize for aging and longevity could have a more general relevance and be extended to other age-related complex traits such as Alzheimer's and Parkinson's diseases. The genetics which emerges for complex traits, including aging and longevity, is thus even more complicated than previously thought, as epistatic interactions between nuclear gene polymorphisms and mtDNA variability (both somatic and inherited) as well as between mtDNA somatic mutations (tissue specific) and mtDNA inherited variants (haplogroups and sub-haplogroups) must be considered as additional players capable of explaining a part of the aging and longevity phenotype. To test this hypothesis is one of the main challenge in the genetics of aging and longevity in the next future

The mitochondrial DNA control region shows genetically correlated levels of heteroplasmy in leukocytes of centenarians and their offspring

<p>Abstract</p> <p>Background</p> <p>Studies on heteroplasmy occurring in the mitochondrial DNA (mtDNA) control region (CR) in leukocytes of centenarians and younger subjects have shown that the C150T somatic transition is over-represented in centenarians. However, whether the occurrence/accumulation of heteroplasmy is a <it>phenotypic consequence </it>of extreme ageing or a <it>genetically controlled event </it>that may favor longevity is a question that deserves further attention. To clarify this point, we set up a Denaturing High Performance Liquid Chromatography (DHPLC) protocol to quantify mtDNA CR heteroplasmy. We then analyzed heteroplasmy in leukocytes of centenarians (100 subjects), their offspring and nieces/nephews (200 subjects, age-range 65–80 years, median age 70 years), and in leukocytes of 114 control subjects sex- and age-matched with the relatives of centenarians.</p> <p>Results</p> <p>The centenarians and their descendants, despite the different ages, showed similar levels of heteroplasmy which were significantly higher than levels in controls. In addition we found that heteroplasmy levels were significantly correlated in parent-offspring pairs (r = 0.263; p = 0.009), but were independent of mtDNA inherited variability (haplogroup and sequence analyses).</p> <p>Conclusion</p> <p>Our findings suggest that the high degree of heteroplasmy observed in centenarians is genetically controlled, and that such genetic control is independent of mtDNA variability and likely due to the nuclear genome.</p