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530 results on '"Ferreiro, J"'

101. Nonlinear Processes in Geophysics

Author

Vázquez, E. Vidal, Moreno, R. García, Miranda, José Garcia Vivas, Díaz, M. C., Requejo, A. Saá, Ferreiro, J. Paz, and Tarquis, A. M.

Abstract

p. 457-468 Submitted by Suelen Reis (suziy.ellen@gmail.com) on 2013-12-09T14:17:05Z No. of bitstreams: 1 10.5194npg-15-457-2008.pdf: 417638 bytes, checksum: cee53a88b458335c0691fc03c6c37df4 (MD5) Approved for entry into archive by Alda Lima da Silva (sivalda@ufba.br) on 2014-02-13T18:13:45Z (GMT) No. of bitstreams: 1 10.5194npg-15-457-2008.pdf: 417638 bytes, checksum: cee53a88b458335c0691fc03c6c37df4 (MD5) Made available in DSpace on 2014-02-13T18:13:45Z (GMT). No. of bitstreams: 1 10.5194npg-15-457-2008.pdf: 417638 bytes, checksum: cee53a88b458335c0691fc03c6c37df4 (MD5) Previous issue date: 2008 Understanding and describing the spatial characteristics of soil surface microrelief are required for modelling overland flow and erosion. We employed the multifractal approach to characterize topographical point elevation data sets acquired by high resolution laser scanning for assessing the effect of simulated rainfall on microrelief decay. Three soil surfaces with different initial states or composition and rather smooth were prepared on microplots and subjected to successive events of simulated rainfall. Soil roughness was measured on a 2×2 mm2 grid, initially, i.e. before rain, and after each simulated storm, yielding a total of thirteen data sets for three rainfall sequences. The vertical microrelief component as described by the statistical index random roughness (RR) exhibited minor changes under rainfall in two out of three study cases, which was due to the imposed wet initial state constraining aggregate breakdown. The effect of cumulative rainfall on microrelief decay was also assessed by multifractal analysis performed with the box-count algorithm. Generalized dimension, Dq, spectra allowed characterization of the spatial variation of soil surface microrelief measured at the microplot scale. These Dq spectra were also sensitive to temporal changes in soil surface microrelief, so that in all the three study rain sequences, the initial soil surface and the surfaces disturbed by successive storms displayed great differences in their degree of multifractality. Therefore, Multifractal parameters best discriminate between successive soil stages under a given rain sequence. Decline of RR and multifractal parameters showed little or no association.

Published
2008
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104. The effect of sewage sludge biochar on peat-based growing media.

Author

Méndez, A., Cárdenas-Aguiar, E., Paz-Ferreiro, J., Plaza, C., and Gascó, G.

Subjects
PEAT as plant growing media, SEWAGE sludge, BIOCHAR, LETTUCE yields, BIOMASS production
Abstract

Peat is the main component of growing media in horticulture. Increasing demand, environmental concerns and rising costs for peat make the search for alternative materials imperative. Much research has been performed aiming to find high quality and low cost substrates from different organic wastes such as compost and thus decrease peat consumption. Biochar is a carbon-rich material that has attracted important research as a soil amendment. However, its potential utilization as a peat substitute for growing media formulation remains less well explored. The aim of this study was to evaluate the effects of sewage sludge and sewage sludge biochar on peat properties as growing media and on lettuce (Lactuca sativa) growth. Sewage sludge transformation into biochar proved to be a sustainable waste management approach in order to promote their future use as growing media components. Addition of biochar from sewage sludge increased the N, P and K content of growing media. The biochar addition to peat at a 10%vol rate increased lettuce biomass production by 184–270% and the shoot length by 137–147% despite hydrophysical properties not being improved. Also, biochar addition had a positive effect on growing media microbial biomass which increased more than 966%. In spite of the higher metal concentration in biochar than in sewage sludge, their transfer to plants seems to be reduced when compared with direct sewage sludge use. [ABSTRACT FROM PUBLISHER]

Published
2017
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108. Neural correlates of abstract verb processing

Author

Rodriguez-Ferreiro, J, Gennari, S P, Davies, R, Cuetos, F, Rodriguez-Ferreiro, J, Gennari, S P, Davies, R, and Cuetos, F

Abstract

The present study investigated the neural correlates of the processing of abstract (low imageability) verbs. An extensive body of literature has investigated concrete versus abstract nouns but little is known about how abstract verbs are processed. Spanish abstract verbs including emotion verbs (e.g., amar, “to love”; molestar, “to annoy”) were compared to concrete verbs (e.g., llevar, “to carry”; arrastrar, “to drag”). Results indicated that abstract verbs elicited stronger activity in regions previously associated with semantic retrieval such as inferior frontal, anterior temporal, and posterior temporal regions, and that concrete and abstract activation networks (compared to that of pseudoverbs) were partially distinct, with concrete verbs eliciting more posterior activity in these regions. In contrast to previous studies investigating nouns, verbs strongly engage both left and right inferior frontal gyri, suggesting, as previously found, that right prefrontal cortex aids difficult semantic retrieval. Together with previous evidence demonstrating nonverbal conceptual roles for the active regions as well as experiential content for abstract word meanings, our results suggest that abstract verbs impose greater demands on semantic retrieval or property integration, and are less consistent with the view that abstract words recruit left-lateralized regions because they activate verbal codes or context, as claimed by proponents of the dual-code theory. Moreover, our results are consistent with distributed accounts of semantic memory because distributed networks may coexist with varying retrieval demands.

Published
2011

110. Biochemical properties in managed grassland soils in a temperate humid zone: modifications of soil quality as a consequence of intensive grassland use.

Author

Paz Ferreiro, J., Trasar-Cepeda, Carmen, Leirós, M. C., Paz Ferreiro, J., Trasar-Cepeda, Carmen, and Leirós, M. C.

Abstract

The maintenance of soil quality is critical for ensuring the sustainability of the environment and the biosphere. Although soil biochemical properties are considered good indicators of changes in soil quality, few studies have been made of the changes in biochemical properties brought about by anthropogenic disturbance of grassland ecosystems. In the present study, several biochemical properties were analysed in 31 grassland soils subjected to a high level of management, and the values obtained were compared with known values corresponding to native grasslands from the same region (Galicia, NW Spain). The 31 managed grasslands were divided in two groups (re-sown grasslands and improved grasslands) according to their management and past land use. The biochemical properties studied were: labile carbon, microbial biomass carbon, microbial respiration, metabolic quotient, net nitrogen mineralization, and the activities of the following enzymes: dehydrogenase, catalase, phosphodiesterase, phosphomonoesterase, casein-protease, BAA-protease, urease, cellulase, ß-glucosidase, invertase and arylsulphatase. Managed grasslands exhibited lower values of soil biochemical properties than native grasslands. Three biochemical equilibrium equations were used to compare soil quality in managed and native grasslands. One of the equations did not show any significant difference between the groups of grassland soils considered. On the contrary, two of the equations showed similar soil quality for improved and native grasslands, while re-sown grasslands exhibited a loss of soil quality when compared to native grassland soils.

Published
2009

126. Percutaneous transhepatic biliary drainage (PTBD) and endoscopic retrograde cholangiopancreatography (ERCP) for malignant obstructive jaundice (OJ) in advanced digestive cancers.

Author

Iruarrizaga, E., primary, Azkona, E., additional, Martinez, M., additional, Iza, E., additional, Lopez-Vivanco, G., additional, Munoz Llarena, A., additional, Ferreiro, J., additional, Ballesteros, D., additional, Fernandez, R., additional, and Rubio, I., additional

Published
2011
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129. Clinical Reasoning: A 35-year-old man with a right hemiplegia and a cerebral mass

Author

Moretta, G., primary, Pettinicchi, J. P., additional, Talarico, M. E., additional, Lopez, P. A., additional, Cerrato, S., additional, Balbuena, M. E., additional, Poderoso, J. J., additional, Mazzocchi, O., additional, Dal Verme, A., additional, Menghi, C., additional, Arcavi, M., additional, Grecco, M. P., additional, and Ferreiro, J. L., additional

Published
2009
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