On the survivability and detectability of terrestrial meteorites on the moon

Materials blasted into space from the surface of early Earth may preserve a unique record of our planet's early surface environment. Armstrong et al. (2002) pointed out that such materials, in the form of terrestrial meteorites, may exist on the Moon and be of considerable astrobiological interest if biomarkers from early Earth are preserved within them. Here, we report results obtained via the AUTODYN hydrocode to calculate the peak pressures within terrestrial meteorites on the lunar surface to assess their likelihood of surviving the impact. Our results confirm the order-of-magnitude estimates of Armstrong et al. (2002) that substantial survivability is to be expected, especially in the case of relatively low velocity (ca. 2.5 km/s) or oblique (≤45°) impacts, or both. We outline possible mechanisms for locating such materials on the Moon and conclude that searching for them would be a scientifically valuable activity for future lunar exploration

Study of mural paintings by Fulvio Pennacchi in São Paulo City by mineralogical techniques

The present research deals with two mural paintings made in 1947 with the fresco technique by Fulvio Pennacchi in the Catholic Chapel of the Hospital das Clínicas (São Paulo City, Brazil), namely the Virgin Annunciation and the Supper at Emmaus. This study regards the materials and painting techniques used by the artist, based on historical research,on in situ observations and laboratory analytical techniques (stereomicroscopy,scanning electron microscopy with an energy dispersive spectrometer, X-ray diffractometry, electron microprobe, images obtained with UV-light), aiming to improve the methods of characterization of objects of our cultural heritage, and to enhance its preservation accordingly. The results lead to the identification of the plaster components and of distinct layers in the frescoes, besides further information on grain size, impurities and textures, composition of pigments, and features of deterioration, such as efflorescences. The degree of degradation of the murals painting was assessed by this way. Our data suggest that a single layer of plaster was used by Pennacchi, as a common mortar with fine- and medium-grained aggregates. Differences in texture were obtained by adding gypsum to the plaster.<br>A presente pesquisa trata de duas pinturas murais feitas em 1947 por Fulvio Pennacchi com a técnica do afresco na Capela Católica do Hospital das Clínicas (São Paulo, Brasil), intituladas Anunciação da Virgem e Ceia de Emaús. Este estudo considera os materiais e as técnicas de pintura usadas pelo artista, baseado na pesquisa histórica, observações in situ e técnicas analíticas de laboratório (estereomicroscopia, microscopia eletrônica de varredura com detector de espectro de energia dispersiva, difração de raios X, microssonda eletrônica, imagens obtidas com luz ultravioleta), visando aperfeiçoar os métodos de caracterização de objetos do nosso patrimônio cultural, e otimizar sua preservação adequadamente. Os resultados conduziram à identificação dos componentes da argamassa e as diferentes camadas nos afrescos, além de informações sobre a granulação, impurezas e texturas, composição dos pigmentos, e feições de deterioração, tal como eflorescência. O grau de degradação das pinturas murais foi avaliado desta maneira. Nossos dados sugerem que Pennacchi usou uma camada única de argamassa com agregados de granulação fina a média. Diferenças na textura foram obtidas pela adição de gesso à argamassa

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Not AvailableConservation agriculture (CA) is being advocated as an alternative to conventional tillage based systems, as it not only holds the potential to enhance soil biological properties, but could also sustain production in the long-run. The impact of long-term tillage and nutrient management on soil biological properties, crops performance, yield and returns were evaluated under maize-mustard rotation. Three tillage practices viz. zero tilled flatbed (ZTFB), permanent bed (PNB) and conventional tillage (CT) along with three nutrient management practices; farmer’s fertilizer practices (FFP), recommended dose of fertilization (RDF) and nutrient expert assisted: site-specific nutrient management (NE®) were tested under the field conditions for six years (2013–2019). ZTFB produced the highest average maize grain yield, which was statistically similar to PNB; however it was 28.4% greater than CT. NE® and RDF recorded 27.4% and 24.8% higher yield over FFP, respectively. Similarly, ZTFB and PNB produced 8.0% greater mustard seed yield than CT, while NE® and RDF had 23.5% and 22.3% greater seed yield compared to FFP. Average of six years indicates, ZTFB and PNB produced 9.7% and 8.9% greater maize grain equivalent yield (MGEY) than CT. Furthermore, NE® and RDF had similar MGEY, but 24.9% and 23% greater than FFP. ZTFB and PNB gave the maximum economic benefits in comparison to CT plots. CT was 18.7% and 19.3% costlier than PNB and ZTFB, while RDF was more expensive than NE® and FFP. Plots under ZTFB and PNB had 13.9% and 17.8% (0.0 0.15 m soil profile) and 14.6% and 12.5% (0.16 0.30 m soil profile) greater soil organic carbon (SOC) than CT plots. These practices also had significant (p<0.05) positive impact on soil biological properties, such as, soil microbial biomass carbon (SMBC), dehydrogenase (DH), alkaline phosphatase (AP) and urease (UA) activities. In 0.0 0.15 m soil layer, NE® had greater values for SOC and SMBC than FFP, but not significantly different to RDF. This study clearly demonstrated that the adoption of conservation tillage (ZTFB / PNB) coupled with NE® and RDF in maize-mustard rotation would definitely improve system MGEY, net returns and soil biological properties in semi-arid regions of the north-west India.Not Availabl