Interaktionen zwischen Genotyp und Ort sind ein Vorteil von lokaler Züchtung von Ackerbohnen (Vicia faba L.)

Organic farming is based on low productivity environments regarding the restricted supply of inputs. Thus, to maximize the response of selection, the local breeding approach was put forward for organic agriculture. To analyse this approach, efforts of organic farmers and scientists were combined in a pertinent, participatory breeding approach using spring faba bean as crop. A set of genotypes with different levels of heterozygosity and heterogeneity were tested in four organic farms and one conventional location. Results for grain yield showed that the genotype-location interaction was highly significant and contributed to a large extent to the yield variation. The findings indicated that indeed local breeding programs could give greater genetic gains for organic cropping systems than traditional, formal plant breeding programs

Heterogeneidad individual e identificabilidad en modelos de captura–recaptura

Individual heterogeneity in detection probabilities is a far more serious problem for capture–recapture modeling than has previously been recognized. In this note, I illustrate that population size is not an identifiable parameter under the general closed population mark–recapture model Mh. The problem of identifiability is obvious if the population includes individuals with pi = 0, but persists even when it is assumed that individual detection probabilities are bounded away from zero. Identifiability may be attained within parametric families of distributions for pi, but not among parametric families of distributions. Consequently, in the presence of individual heterogeneity in detection probability, capture–recapture analysis is strongly model dependent.La heterogeneidad individual en las probabilidades de detección representa un problema para la modelación del procedimiento de captura–recaptura mucho más serio de lo que previamente se había reconocido. En este artículo se demuestra que el tamaño de la población no constituye un parámetro identificable en el modelo general Mh que emplea técnicas de marcaje–recaptura de poblaciones cerradas. El problema de la identificabilidad resulta evidente si la población incluye individuos con pi = 0, pero sigue persistiendo aun cuando se presuponga que las probabilidades de detección individual se han alejado de cero. La identificabilidad puede conseguirse en familias paramétricas de distribuciones para pi, pero no entre familias paramétricas de distribuciones. Por consiguiente, si se da una heterogeneidad individual en la probabilidad de detección, el análisis de captura–recaptura depende considerablemente del modelo considerado

Precision Counting of Small Black Holes

It has recently been proposed that a class of supersymmetric higher-derivative interactions in N=2 supergravity may encapsulate an infinite number of finite size corrections to the microscopic entropy of certain supersymmetric black holes. If this proposal is correct, it allows one to probe the string theory description of black-hole micro-states to far greater accuracy than has been possible before. We test this proposal for ``small'' black holes whose microscopic degeneracies can be computed exactly by counting the corresponding perturbative BPS states. We also study the ``black hole partition sum'' using general properties of of BPS degeneracies. This complements and extends our earlier work in hep-th/0502157Comment: 103 pages, uses JHEP3.cl

Social Construction and White Attitudes toward Equal Opportunity and Multiculturalism

As the United States moves from being a predominantly biracial to a multiracial society, racial attitudes continue to become more diverse and more complex. Scholars need to address these changes not only in terms of black and white Americans, but also how these changes involve and affect other racial groups, particularly Asian and Hispanic Americans. This inquiry looks at some of these complexities by examining how social construction differentials in the minds of white Americans affect their attitudes toward the issues of equal opportunity and multiculturalism. The analysis shows that differences in the cognitive images whites hold of minority groups in comparison to their own race have a significant impact in determining white attitudes toward group-based issues. In effect, negative constructions of racial groups lower one\u27s support for policies aimed at these groups

The Answering Machine Generation - Who Are They and What Problem Do They Pose for Survey Research

Increased incidence of telephone answering machines and the use of such devices to screen calls pose a potential threat to the representativeness of samples in telephone surveys. Using data from nine statewide surveys, this analysis examines the extent to which answering machines are used to screen calls and the demographic characteristics associated with answering machine use and call screening. Results show that at most two to three percent of households use answering machines to screen calls, and that such screening is more likely to take place in households with higher family incomes, outside rural areas, and which include individuals who are younger and have higher levels of education. While call screening does not presently threaten the representativeness of samples in telephone surveys, the increased incidence of answering machines together with the increased percentage of households indicating these devices are sometimes used to screen calls demonstrate that the potential bias from this source is growing

Educação sob o Nacional-Socialismo. Ideologia, Programas e Prática

The article provides a condensed, introductory overview of National Socialist formation education in the Hitler Youth and school. It is based on the author’s own research and relevant presentations. Education under National Socialism was characterized by the interplay of a racist worldview and the regime’s totalitarian will to rule. For Nazi education, this meant that the political took precedence over all social issues, including all issues relevant from the perspective of educational theory. In our analysis, we distinguish between two levels: the level of standardization and the level of educational practices in the Hitler Youth and school. Particularly during World War II, political demands were increasingly rigidly enforced, and adolescents were increasingly instrumentalized for their purposes. The National Socialists’ aspirations for total control compared to the educational reality exhibited correspondences as well as discrepancies and contradictions. Against the background of traditional tasks of education, the verdict on Nazi education from a normative point of view is clearly negative. However, if one also looks at National Socialist educational practices, one notices numerous characteristic ambivalences – between the partly contradictory demands of the National Socialist regime, but also between its educational practices and its attempts at realization. On the one hand, National Socialists achieved comprehensive formative successes, while on the other hand they often failed because of their totalitarian objectives