Circular sets of primes of imaginary quadratic number fields

Let p be an odd prime number and let K be an imaginary quadratic number field whose class number is not divisible by p. For a set S of primes of K whose norm is congruent to 1 modulo p, we introduce the notion of strict circularity. We show that if S is strictly circular, then the group G(KS(p)=K) is of cohomological dimension 2 and give some explicit examples

Development of a game for the evaluation of operative structure in teenagers with down syndrome

When an individual presents some type of intellectual disability, there is a tendency to expose him to innumerous evaluations, repeating them several times in a short period so as to verify his development. In some cases, the evaluation is tiring and could lead to the desistance of the person evaluated and to the exhaustion of the appraiser. In this article a computational game was developed in Flash for teenagers with the Down Syndrome that demonstrate light or moderate intellectual disability to evaluate cognitive seriation functions and classes inclusion based on the Jean Piaget theory. The game is set up in a kitchen where the individual to be evaluated helps the principal character in achieving tasks. After the termination of the activities a report is made with the analysis of the operative structures demonstrated. To evaluate the efficiency of the game, the subjects went through the evaluation of the operative tests and then played the game. Two pilot tests were made and applied to 13 teenagers with the Down Syndrome. The analysis showed that the method minimizes subjectivity and manipulation of the material needing less time making the report as the game is produced immediately. There was a bigger interest because the game contextualizes the tests even when the individual had verbal difficulty the evaluation access was possible through the game which didn´t occur when applied in the real tests

Massey products in the Galois cohomology of number fields

We study the relation structure of the Galois group of the maximal outside a finite set of primes unramified p-extension of Q and of the Galois group of the p-class field tower of a quadratic number field. This relation structure is described in terms of Massey products in the Galois cohomology of number fields. A connection is given to Milnor invariants and Redei symbols. In particluar, we prove a number theoretic analogue of the theorem of Porter and Turaev from link theory

Heme iron from meat and risk of colorectal cancer: a meta-analysis and a review of the mechanisms involved

Red meat and processed meat intake is associated with a risk of colorectal cancer, a major cause of death in affluent countries. Epidemiological and experimental evidence supports the hypothesis that heme iron present in meat promotes colorectal cancer. This meta-analysis of prospective cohort studies of colon cancer reporting heme intake included 566,607 individuals and 4,734 cases of colon cancer. The summary relative risk of colon cancer was 1.18 [95%C.I.: 1.06-1.32] for subjects in the highest category of heme iron intake compared with those in the lowest category. Epidemiological data thus show a suggestive association between dietary heme and risk of colon cancer. The analysis of experimental studies in rats with chemically-induced colon cancer showed that dietary hemoglobin and red meat consistently promote aberrant crypt foci, a putative pre-cancer lesion. The mechanism is not known, but heme iron has a catalytic effect on (i) the endogenous formation of carcinogenic N-nitroso compounds and (ii) the formation of cytotoxic and genotoxic aldehydes by lipoperoxidation. A review of evidence supporting these hypotheses suggests that both pathways are involved in heme iron toxicit

Eine Untersuchung der Darstellungswahl bei der Nutzung der Heidelberger Mathematik-Medienplattform MaMpf

Eine wesentliche Aufgabe von Studierenden der Mathematik lässt sich darin beschreiben, dass diese die dargebotenen abstrakten Inhalte und Strukturen erfassen, mit vorhandenem Wissen vernetzen und darüber hinaus sich selbstständig neues mathematisches Wissen aneignen. Ein wesentliches Kennzeichen der Strukturen mathematischer Begrifflichkeiten ist ihre hierarchische Anordnung. Die deduktive logische Struktur der Sachebene ist jedoch von der Ebene der Vorstellungen dazu abzugrenzen (Tall & Vinner, 1981). Entsprechend gilt es, beide Ebenen im Vorlesungsbetrieb voneinander zu trennen, wenn tragfähige Vorstellungen (Vogel & Wittmann, 2010) mathematischer Begrifflichkeiten und eigenständige mathematische Arbeitsweisen als prozedurales Wissen (Anderson, 2001) angebahnt werden sollen. Die Herausforderung besteht darin, die im Fortgang der Mathematik entstandene deduktive Welt mathematischen Wissens um Problemstrukturen, denen optimale Lösungen zugeführt wurden, den Studierenden so zugänglich zu machen, dass diese Gelegenheiten zum eigenen mathematischen Tun und zur persönlichen Ausgestaltung von Lernwegen erhalten. Hierzu bedarf es der Bereitstellung mathematischer Entdeckungsräume, die adaptiv gestaltet individuelle Möglichkeiten der Anknüpfung und der Unterstützung im eigenaktiven Lernprozess bieten. Eine bloße Stoffdarbietung, bei der eigentliche Mathematik als Fertigfabrikat vermittelt wird (Freudenthal, 1973), kann diesen Anspruch nicht einlösen. Den Lernenden verbleibt in diesem Fall die Rolle des rezeptiven Zuschauers, Platz für eigenes mathematisches Tun im Sinne kognitiver Aktivierung (Kunter & Trautwein, 2013) ist nicht gegeben

Análisis de la diversidad genética del maqui (Aristotelia chilensis) en plantas procedentes de distintas localidades en Chile

62 p.Aristotelia chilensis es una planta silvestre, dioica, que requiere obligadamente de polinización cruzada para producir sus frutos. Es una especie que se encuentra en procesos de domesticación y que posee un gran potencial económico dado los efectos antioxidantes y las propiedades medicinales de los constituyentes químicos que poseen sus frutos y hojas. En esta memoria se realizó un análisis de la variabilidad genética en muestras de A. chilensis provenientes de ocho localidades ubicadas entre la V y la X región de Chile. Se probaron 12 parejas de partidores universales en un total de 58 individuos para amplificar fragmentos de ADN genómico mediante la técnica de AFLP. Los pares M63/E35 y M74/E35 amplificaron positivamente y arrojaron un total de 259 fragmentos polimórficos. Se analizó también la variación de regiones microsatélites de ADN de cloroplasto, probándose 10 parejas de partidores de los cuales solo ccmp5 y ccmp6 arrojaron polimorfismos. Se detectaron dos haplotipos: el haplotipo 1 (119 pb-88 pb) y el haplotipo 2 (120 pb-87 pb). Ambos haplotipos se caracterizaron por estar presentes en el extremo norte de la zona central, en tanto que el haplotipo 2 se presentó sólo en localidades de la zona centro sur de Chile. El análisis de varianza molecular (AMOVA) mostró que el 95% de la variación genética total fue encontrada dentro de cada localidad, mientras que solo el 5 % de la variación correspondió a variación entre las localidades. Un análisis de aislamiento por distancia mostró una correlación positiva entre distancia genética y distancia geográfica. Un análisis de agrupamiento genético jerárquico arrojó un dendrograma UPGMA el cual no presentó formación de grupos genéticos. Finalmente, un análisis de agrupamiento bayesiano arrojó que A. chilensis conforma cuatro grupos genéticos. Este último análisis permite concluir que las muestras analizadas de A. chilensis provenientes de las ocho localidades analizadas, constituyen distintos grupos genéticos, donde cada individuo presenta fracciones de grupos genéticos en distinta proporción.Palabras clave: AFLP, microsatélite de cloroplasto, partidores, haplotipo y grupos genéticos./ABSTRACT: Aristotelia chilensis (Maqui) is a wild dioecious plant, which requires an obligated cross pollination to produce fruit. This specie is in the process to domestication and has a great economic potential due to its antioxidant and medicinal properties given by the chemical constituents in fruits and leaves. In this study the genetic variability of samples of A. chilensis, coming from eight localities between V and X region of Chile was analyzed. Twelve pairs of universal primers were tested in a total of 58 individuals to amplify genomic DNA fragments using the AFLP technique. The M63/E35 and M74/E35 AFLP primer pairs amplified positively and displayed 259 polymorphic fragments. The variation in chloroplast microsatellite DNA region was evaluated using ten primer pairs, from which only ccmp5 and ccmp6 exhibited polymorphism. Two haplotypes were detected, haplotype 1 (119bp-88bp) and haplotype 2 (120bp-87bp). Both haplotypes were found in the northern end of the central zone, whereas haplotype 2 were only found in the south-central zone and south zone of Chile. Analysis of molecular variance showed that 95% of the total genetic variation was found within each locality, while only 5% of the variation was accounted by between locations. An analysis of isolation by distance showed a positive correlation between genetic distance and geographic distance. A genetic analysis of hierarchical clustering showed no information of genetic groups. Finally, a Bayesian clustering analysis showed that A. chilensis formed four genetic groups. This final analysis suggests that the samples studied conform distinct genetic groups, where each individual has fractions in different proportions. Keywords: AFLP, chloroplast microsatellite, primers, haplotype and genetic groups

Back to the future of soil metagenomics

JN was funded by a fellowship from the French MENESR.Peer reviewedPeer Reviewe

How Can the EU Beating Cancer Plan Help in Tackling Lung Cancer, Colorectal Cancer, Breast Cancer and Melanoma?

Cancer is the second leading cause of mortality in EU countries, and the needs to tackle cancer are obvious. New scientific understanding, techniques and methodologies are opening up horizons for significant improvements in diagnosis and care. However, take-up is uneven, research needs and potential outstrip currently available resources, manifestly beneficial practices—such as population-level screening for lung cancer—are still not generalised, and the quality of life of patients and survivors is only beginning to be given attention it merits. This paper, mainly based on a series of multistakeholder expert workshops organised by the European Alliance for Personalised Medicine (EAPM), looks at some of those specifics in the interest of planning a way forward. Part of this exercise also involves taking account of the specific nature of Europe and its constituent countries, where the complexities of planning a way forward are redoubled by the wide variations in national and regional approaches to cancer, local epidemiology and the wide disparities in health systems. Despite all the differences between cancers and national and regional resources and approaches to cancer care, there is a common objective in pursuing broader and more equal access to the best available care for all European citizens

How Can the EU Beating Cancer Plan Help in Tackling Lung Cancer, Colorectal Cancer, Breast Cancer and Melanoma?

Cancer is the second leading cause of mortality in EU countries, and the needs to tackle cancer are obvious. New scientific understanding, techniques and methodologies are opening up horizons for significant improvements in diagnosis and care. However, take-up is uneven, research needs and potential outstrip currently available resources, manifestly beneficial practices—such as population-level screening for lung cancer—are still not generalised, and the quality of life of patients and survivors is only beginning to be given attention it merits. This paper, mainly based on a series of multistakeholder expert workshops organised by the European Alliance for Personalised Medicine (EAPM), looks at some of those specifics in the interest of planning a way forward. Part of this exercise also involves taking account of the specific nature of Europe and its constituent countries, where the complexities of planning a way forward are redoubled by the wide variations in national and regional approaches to cancer, local epidemiology and the wide disparities in health systems. Despite all the differences between cancers and national and regional resources and approaches to cancer care, there is a common objective in pursuing broader and more equal access to the best available care for all European citizens