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Ectomycorrhizal (ECM) symbioses are among the most widespread associations between roots of woody plants and soil fungi in forest ecosystems. These associations contribute significantly to the sustainability and sustainagility of these ecosystems through nutrient cycling and carbon sequestration. Unfortunately, the molecular mechanisms controlling the mutual recognition between both partners are still poorly understood. Elegant work has demonstrated that effector proteins from ECM and arbuscular mycorrhizal (AM) fungi regulate host defenses by manipulating plant hormonal pathways. In parallel, genetic and evolutionary studies in legumes showed that a ‘common symbiosis pathway’ is required for the establishment of the ancientAM symbiosis and has been recruited for the rhizobia–legume association. Given that genes of this pathway are present in many angiosperm trees that develop ectomycorrhizas, we propose their potential involvement in some but not all ECM associations. The maintenance of a successful long-term relationship seems strongly regulated by resource allocation between symbiotic partners, suggesting that nutrients themselves may serve as signals. This review summarizes our current knowledge on the early and late signal exchanges between woody plants and ECM fungi, and we suggest future directions for decoding the molecular basis of the underground dance between trees and their favorite fungal partners.

Climate change effects on seasonal activity in terrestrial ecosystems are significant and well documented, especially in the middle and higher latitudes. Temperature is a main driver of many plant developmental processes, and in many cases higher temperatures have been shown to speed up plant development and lead to earlier switching to the next ontogenetic stage. Qualitatively consistent advancement of vegetation activity in spring has been documented using three independent methods, based on ground observations, remote sensing, and analysis of the atmospheric CO2 signal. However, estimates of the trends for advancement obtained using the same method differ substantially. We propose that a high fraction of this uncertainty is related to the time frame analysed and changes in trends at decadal time scales. Furthermore, the correlation between estimates of the initiation of spring activity derived from ground observations and remote sensing at interannual time scales is often weak. We propose that this is caused by qualitative differences in the traits observed using the two methods, as well as the mixture of different ecosystems and species within the satellite scenes.

Existing research on policy diffusion focuses almost exclusively on \"successes\" where many jurisdictions adopted the policy or policies under examination. Some have speculated that this \"pro-innovation bias\" compromises scholars' ability to draw valid inferences about the factors that influence the diffusion process. We argue that the study of interstate compacts in the United States provides an analytic opportunity to assess whether these concerns are warranted because it allows us to examine an entire universe of cases with unusually wide variability in their adoption patterns. Based on a pooled event history analysis of the interstate compacts that are open to all fifty states, we conclude that the tendency to limit diffusion research to widely adopted policies affects the results of previous studies. Specifically, it appears to lead scholars to systematically overestimate the impact of geographic diffusion pressures and policy attributes, and to underestimate the importance of professional associations and the opportunity to learn from previous adoptions. In sum, the longstanding concerns about a pro-innovation bias in diffusion research seem to be warranted.

The literature overwhelmingly demonstrates that feelings of ease are good and that objects that are easy to process are much liked. We propose, and demonstrate across three experiments, that this is not the case when people are pursuing a goal. This is because people pursuing a goal (e.g., \"become kinder\") usually invest efforts in whichever means (e.g., donate to a particular charity) they perceive as most instrumental for attaining their goal. Consequently, in their minds there is a correspondence between instrumentality of a means and feelings of effort. This correspondence becomes reversed in people's minds during goal pursuit, and they also come to view an object that is associated with feelings of effort rather than ease as more instrumental for goal attainment and consequently more desirable. When an object is not a means to fulfill an accessible goal, or when goals relating to the means are not accessible, subjective feelings of ease improve evaluation, as found in previous research on ease of processing.

Manganese (Mn) is an essential metal nutrient for plants. Recently, some of the genes responsible for transition metal transport in plants have been identified; however, only relatively recently have Mn2+ transport pathways begun to be identified at the molecular level. These include transporters responsible for Mn accumulation into the cell and release from various organelles, and for active sequestration into endomembrane compartments, particularly the vacuole and the endoplasmic reticulum. Several transporter gene families have been implicated in Mn2+ transport, including $cation/H^+$ antiporters, natural resistance-associated macrophage protein (Nramp) transporters, zinc-regulated transporter/iron-regulated transporter (ZRT/IRT1)-related protein (ZIP) transporters, the cation diffusion facilitator (CDF) transporter family, and P-type ATPases. The identification of mutants with altered Mn phenotypes can allow the identification of novel components in Mn homeostasis. In addition, the characterization of Mn hyperaccumulator plants can increase our understanding of how plants can adapt to excess Mn, and ultimately allow the identification of genes that confer this stress tolerance. The identification of genes responsible for Mn2+ transport has substantially improved our understanding of plant Mn homeostasis.

This note reviews the targeting performance of Bolsa Família and its impact on inequality, poverty, consumption, education, health care, and labor force participation. Bolsa Família has several design and implementation characteristics that distance it from a pure human-capital-based conditional cash transfer model. For that reason, we compare the impact of Bolsa Família to that of other conditional cash transfer programs in Latin America, such as in Mexico, Colombia, Ecuador, and Chile. We show that, as have other programs, Bolsa Família has helped reduce inequality and extreme poverty and has improved education outcomes, without having a negative impact on labor force participation. Where the program has failed to have its intended impact, in health and nutrition, supply-side constraints seem to be the principal problem. Esta nota resume a performance do Programa Bolsa Família em termos de sua focalização e seu impacto sobre desigualdade, pobreza, consumo, educação, saúde e participação na força de trabalho. O desenho e a implementação do Bolsa Família apresenta características que o distanciam de um programa \"puro\"de transferência condicionada de renda baseado no capital humano. Por este motivo, nós comparamos o impacto do Bolsa Família com o de outros programas de transferências condicionadas da América Latina, como aqueles do México, Colômbia, Equador e Chile. Nós mostramos que assim como outros programas, o Bolsa Família ajudou a reduzir a desigualdade e a extrema pobreza e teve impactos positivos sobre indicadores educacionais, sem apresentar resultados negativos sobre a participação na força de trabalho. Nas áreas onde resultados positivos não foram encontrados como saúde e nutrição, restrições da oferta parecem ser o principal problem.a

Drawing on six months of ethnographic fieldwork in the main welfare office of the city of Buenos Aires, this article dissects poor people's lived experiences of waiting. The article examines the welfare office as a site of intense sociability amidst pervasive uncertainty. Poor people's waiting experiences persuade the destitute of the need to be patient, thus conveying the implicit state request to be compliant clients. An analysis of the sociocultural dynamics of waiting helps us understand how (and why) welfare clients become not citizens but patients of the state. Basado en seis meses de trabajo etnográfico en la sala de espera del Ministerio de Desarrollo Social de la ciudad de Buenos Aires, este trabajo examina las experiencias que los pobres urbanos tienen de la espera. El artículo estudia la sala de espera como un sitio de intensa sociabilidad en medio de una generalizada incertidumbre. Las experiencias de la espera convencen a los destituidos que tienen que ser pacientes, transmitiendo—de manera implícita—un mensaje estatal: tienen que ser beneficiarios sumisos. Un análisis de las dinámicas socioculturales de la espera nos ayuda a entender cómo (y porqué) los beneficiarios de los programas de asistencia se convierten no en ciudadanos sino en pacientes del estado.

We present a new data set on the left-right placement of major Brazilian political parties serving in the first five legislatures under democracy. On the basis of survey responses of more than 850 federal legislators from 1990 to 2005, we generate party placements on an ideological scale where 1 = \"left\" and 10 = \"right.\" The data are rescaled to account for idiosyncrasies in responses as well as variation in use of the survey scale across time. We discuss both the validity and the reliability of our new measures by comparing them to other data sets. We further discuss three substantive issues that the data reveal. First, ideological polarization has moderated over time. Second, the median legislator has shifted noticeably to the left and now stands equidistant from the influential PT and PSDB, the parties that have anchored recent presidential elections. Third, Brazilian political elites continue to shun self-identifications associated with political conservatism or neoliberalism. /// Este artigo apresenta uma nova classificação ideológica dos principais partidos brasileiros durante as cinco primeiras legislaturas do atual período democrático. Utilizando como base surveys realizados entre 1990 e 2005 com 850 legisladores federais, estimamos as posições ideológicas dos partidos numa escala 1-10. A estimação leva em conta tanto a variação na interpretação da escala original por legisaltores individuais, quanto mudanças no significado da escala no tempo. Analizamos a validade e a confiabilidade das nossas medidas através de uma comparação com outras bases similares, e discutimos três padrões revelados por nossas estimativas, quais sejam: (1) polarização ideológica é menor hoje do que quando do retorno à democracia, (2) o legislador mediano está mais à esquerda do que no início do período analizado, e (3) elites politicas continuam evitando associações com a idéia de consevadorismo.

What is the impact of exposure to criminal violence on support for political institutions in Latin America? The increase in criminal violence in the region since the return to democratic rule makes this a timely question. Several scholars have demonstrated the impact of a series of variables (political performance, economic performance, interpersonal trust, perception of corruption) on citizens' support for political institutions (system support). The goal of this study is to assess the impact of two additional variables (victimization and perception of violence) that have been neglected in the literature. I test the impact of exposure to violence on system support by using survey data from the 2004 edition of the Latin American Public Opinion Project. My findings demonstrate that both victimization and high perception of violence have a negative impact on system support in Latin America. ¿Cuál es el impacto de la exposición a la violencia sobre el apoyo sistèmico a las instituciones políticas en América Latina? El aumento de la violencia criminal en la región desde el retorno a la democracia provee una oportunidad para intentar responder a esta pregunta. Varios investigadores demostraron que una serie de variables (performance política, performance económica, confianza interpersonal, percepción de corrupción) tienen un impacto importante sobre el apoyo de los ciudadanos a las instituciones políticas. El objetivo de este estudio es analizar el impacto de dos variables adicionales (victimización y percepción de violencia) que fueron menos estudiadas en la literatura de comportamiento político. Analizo el impacto de exposición a la violencia sobre el apoyo a las instituciones políticas usando la edición 2004 de las encuestas del Latin American Public Opinion Project. Mis resultados demuestran que tanto victimización como percepción de violencia tienen un impacto negativo sobre el apoyo a las instituciones políticas en América Latina.

This article briefly summarizes findings from a review of 95 empirical studies of games used in instruction. The article suggests that such efforts are best assessed as transfer from game play to performance on external tasks that are targeted by the instruction. Review findings suggest that such transfer may be expected only if the cognitive processes engaged by games and external tasks overlap. Integrating games into a course of study is likely to facilitate such transfer. Research on improvement in cognitive processes as a result of playing \"first-person shooter\" games is briefly overviewed, and suggestions for similar research not using aggressive content are made. Minimal overlap between this and another research review of the effects of games used in instruction is discussed, and the need for generally accepted definitions and a taxonomy of games is noted.