3,473 research outputs found

    Tectonics and fluvial dynamism affecting the Tiber River in prehistoric Rome

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    Open access funding provided by Istituto Nazionale di Geofisica e Vulcanologia within the CRUI-CARE Agreement. Research funding was provided by Loeb Classical Library Foundation, Gerda Henkel Foundation, American Philosophical Society, Etruscan Foundation, Fondazione Lemmermann, University of Michigan, University of St Andrews, and the Leverhulme Trust.Geomorphological investigations in Rome’s river valley are revealing the dynamism of the prehistoric landscape. It is becoming increasingly apparent that paleogeographic conditions that defined Rome in the historical era are the product of changes since the Bronze Age, which may be the result of local fault activity in addition to fluvial dynamism. Through a dedicated borehole chronostratigraphic study, integrated by 14C and archaeological dates, and paleomagnetic investigations, we offer here new evidence for fault displacement since ca. 4500 years/BP. We present the failure of the sedimentary fabric of a clay horizon caused by liquefaction processes commonly linked with seismic shaking, interpreting an (ca. 4 m) offset to signify the existence of a fault line located at the foot of the Capitoline Hill. In addition, we show evidence for another (ca. 1 m) offset affecting a stratigraphic horizon in the river channel, occurring along another hypothesized fault line crossing through the Tiber Valley. Movement along this fault may have contributed to a documented phase of fast overflooding dated to the sixth century BCE which eventually led to the birth of the Tiber Island. The most plausible scenario implies progressive deformation, with an average tectonic rate of 2 mm/year, along these inferred fault lines. This process was likely punctuated with moderate earthquakes, but no large event necessarily occurred. Together, the available evidence suggests that during the early centuries of sedentary habitation at the site of Rome, active fault lines contributed to significant changes to the Tiber River valley, capable of challenging lowland activities.Publisher PDFPeer reviewe

    Molecular, behavioral and anatomical sophistication in spider webs: insights from spinning gland RNA-seq experiments in primitive and modern spiders.

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    RNA-seq experiments conducted in 454 sequencers were carried out to produce 87.000 short-reads representing the transcriptome of two spiders'spinning glands. We produced sequences from (i) Actinopus sp., a spider from the Mygalomorphae clade, and (ii) Gasteracantha cancriformis, an Orbicularia spider. Mygalomorphae spiders are known to retain a number of primitive morphological and behavioral characters. They use mixtures of a primitive web, soil, and plants only to cover a burrow they make on the ground for shelter and predation.On the other hand, Orbicularia spiders show a number of derivative spider's characters and they are capable to build different and complex silks used in a variety of situations. It is interesting to note that the complexity of web production, usage and behavior in these spiders is reflected both by (i) the variety of the repertoire of protein molecules (spidroins) they use to make their webs and (ii) the complexity of their anatomical spinning gland apparatu used to produce silk. Here we have first conducted a broad analysis of the spinning gland transcriptome in both spiders producing unigenes and categorizing annotated genes in biological functions.Then we started to analyze the number and variety of spider silk proteins and families found in different spider clades.We have shown that spiders using web only for a limited number of situations present a less sophisticated morphological spinning apparatus and produce a small repertoire of spidroin molecules. Phylogenetic analyses were conductedin the 3'region of spidroins and we try to relate (i) the evolution of silk protein families,(ii) the evolutionary complexification of silk production behavior and web usage, and (iii) the appearance of new specialized spinning glands along the evolution of specimens and clades in the Araneae order

    Cultivo agroecológico do cafeeiro: produtividade de cultivares em sistema solteiro e consorciado com bananeira.

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    bitstream/item/68473/1/039-Cultivo-agroecologico-do-cafeeiro.pdfPublicado também no Cadernos de Agroecologia, v. 7, n. 2, 2012

    Avaliação de substratos de húmus de minhoca na produção de mudas de alface (Lactuca sativa) cultivar Lucy Brown.

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    bitstream/item/68817/1/020-nascimento-avaliacao.pdfPublicado também no Cadernos de Agroecologia, v. 7, n.2, 2012

    Incidência de bicho-mineiro em diferentes cultivares de cafeeiro em sistema agroecológico.

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    bitstream/item/68482/1/061-Incidencia-de-bicho-mineiro-em-diferentes-cultivares-de-cafeeiro.pdfPublicado também no Cadernos de Agroecologia, v. 7, n. 2, 2012

    Boletim agrometeorológico: Município de Miracema, 2002.

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    O presente Boletim Agrometeorológico apresenta informações coletadas pela estação agrometeorológica do projeto RADEMA instalada na fazenda Santa Rosa, a única dentro do município de Miracema, Estado do Rio de Janeiro. São apresentados os resultados de 2002 referentes ao primeiro ano do projeto, os quais são postos à disposição da sociedade para o uso adequado.bitstream/CNPS/11565/1/boletim_agro.pd

    ACS Observations of a Strongly Lensed Arc in a Field Elliptical

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    We report the discovery of a strongly lensed arc system around a field elliptical galaxy in Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) images of a parallel field observed during NICMOS observations of the HST Ultra-Deep Field. The ACS parallel data comprise deep imaging in the F435W, F606W, F775W, and F850LP bandpasses. The main arc is at a radius of 1.6 arcsec from the galaxy center and subtends about 120 deg. Spectroscopic follow-up at Magellan Observatory yields a redshift z=0.6174 for the lensing galaxy, and we photometrically estimate z_phot = 2.4\pm0.3 for the arc. We also identify a likely counter-arc at a radius of 0.6 arcsec, which shows structure similar to that seen in the main arc. We model this system and find a good fit to an elliptical isothermal potential of velocity dispersion σ300\sigma \approx 300 \kms, the value expected from the fundamental plane, and some external shear. Several other galaxies in the field have colors similar to the lensing galaxy and likely make up a small group.Comment: Accepted for publication in ApJ Letters. 10 pages, 3 figures. Figures have been degraded to meet size limit; a higher resolution version and addtional pictures available at http://acs.pha.jhu.edu/~jpb/UDFparc
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