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The spin-projector operators for symmetric rank-2 tensors are reassessed in connection with the issue of topologically massive gravity. The original proposal by Barnes and Rivers is generalised to account for D-dimensional Einstein gravity and 3-dimensional Chern-Simons massive gravitation.

In a coupled-channel model, we explore the effects of coupling between configurations on the radial behavior of the wave function and, in particular, on the spectroscopic factor (SF) and the asymptotic normalization coefficient (ANC). We evaluate the extraction of a SF from the ratio of the ANC of the coupled-channel model to that of a single-particle approximation of the wave function. We perform this study within a core + n collective model, which includes two states of the core that connect by a rotational coupling. To get additional insights, we also use a simplified model that takes a delta function for the coupling potential. Calculations are performed for 11Be. Fair agreement is obtained between the SF inferred from the single-particle approximation and the one obtained within the coupled-channel models. Significant discrepancies are observed only for large coupling strength and/or large admixture, that is, a small SF. This suggests that reliable SFs can be deduced from the wave-function asymptotics when the structure is dominated by one configuration, that is, for a large SF.Comment: Title correcte

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In analyzing the evolution of pedologic mapping perspectives in Brazil, it is noteworthy that they are based firmly on geology and focused on soil aptitude for agricultural use. Mapping detail was improved between the decades of 1950 and 1980. The mapping initially concentrated in the Northeast and Southeast regions, shifting its orientation in recent decades with the opening of the Brazilian agricultural frontiers. Remote sensing, geographical information systems, and informatics allowed increased map detail and promoted technological changes in map production. This revolution provided the development of digital soil mapping (DSM) as a set of methods and techniques to automate the soil surveys in Brazil. Despite the technological advances, only 1% of the Brazilian territory has soil maps on the scale of 1:25,000. In 1990 for economical, technological, and methodological reasons there was a decrease in both surveying and detailing processes. In a response to this reality Brazil has used new software and technologies, as well as the accumulated knowledge, to increase technological development of soil surveys. The integration of existing techniques and data favor the faster construction of more detailed and more interactive soil maps for a larger parcel of the country. This perspective, as the former one, will require some modifications to the soil mapping both in the methodology and also in the approach.

Os Tabuleiros Costeiros constituem uma unidade geomorfológica desenvolvida sobre o Grupo Barreiras, que apresenta grande extensão territorial e solos que sustentam diversas atividades produtivas, dentre elas a silvicultura e a citricultura. Os solos dos Tabuleiros Costeiros apresentam limitações físicas e químicas pouco entendidas, o que justifica ainda a realização de estudos genéticos. Por isso, estudou-se a origem e evolução de solos vermelhos e amarelos através de uma topossequência no Litoral Norte do estado da Bahia, bem como os mecanismos envolvidos na conformação de horizontes coesos. Os dados indicam que os solos vermelhos se formaram a partir de arenitos lamosos conglomeráticos e arenitos lamosos do Grupo Barreiras e se transformaram em amarelos. A gênese dos solos vermelhos foi acompanhada pela conformação de horizontes coesos, que se tornaram mais endurecidos e espessos com a evolução da cobertura pedológica para amarela, o que ocorreu pari passu com a diminuição dos teores de ferro livre, degradação do plasma argiloso dos horizontes superficiais e avanço da argiluviação. Atualmente, a topossequência está passando por um processo de podzolização, devido à influência da neotectônica, responsável pela formação de uma depressão fechada que acumula água após episódios de chuva, criando um ambiente hidromórfico temporário que acentua a degradação.

Elevated CO2 (eCO2) has been reported to cause mineral losses in several important food crops such as soybean (Glycine max L.) and common bean (Phaseolus vulgaris L.). In addition, more than 30% of the world’s arable land is calcareous, leading to iron (Fe) deficiency chlorosis and lower Fe levels in plant tissues. We hypothesize that there will be combinatorial effects of eCO2 and Fe deficiency on the mineral dynamics of these crops at a morphological, biochemical and physiological level. To test this hypothesis, plants were grown hydroponically under Fe sufficiency (20 μM Fe-EDDHA) or deficiency (0 μM Fe-EDDHA) at ambient CO2 (aCO2, 400 ppm) or eCO2 (800 ppm). Plants of both species exposed to eCO2 and Fe deficiency showed the lowest biomass accumulation and the lowest root: shoot ratio. Soybean at eCO2 had significantly higher chlorophyll levels (81%, p < 0.0001) and common bean had significantly higher photosynthetic rates (60%, p < 0.05) but only under Fe sufficiency. In addition, eCO2 increased ferric chelate reductase acivity (FCR) in Fe-sufficient soybean by 4-fold (p < 0.1) and in Fe-deficient common bean plants by 10-fold (p < 0.0001). In common bean, an interactive effect of both environmental factors was observed, resulting in the lowest root Fe levels. The lowering of Fe accumulation in both crops under eCO2 may be linked to the low root citrate accumulation in these plants when grown with unrestricted Fe supply. No changes were observed for malate in soybean, but in common bean, shoot levels were significantly lower under Fe deficiency (77%, p < 0.05) and Fe sufficiency (98%, p < 0.001). These results suggest that the mechanisms involved in reduced Fe accumulation caused by eCO2 and Fe deficiency may not be independent, and an interaction of these factors may lead to further reduced Fe levels.