2,449 research outputs found
A constitutive model for unsaturated cemented soils under cyclic loading
On the basis of plastic bounding surface model, the damage theory for
structured soils and unsaturated soil mechanics, an elastoplastic model for
unsaturated loessic soils under cyclic loading has been elaborated. Firstly,
the description of bond degradation in a damage framework is given, linking the
damage of soil's structure to the accumulated strain. The Barcelona Basic Model
(BBM) was considered for the suction effects. The elastoplastic model is then
integrated into a bounding surface plasticity framework in order to model
strain accumulation along cyclic loading, even under small stress levels. The
validation of the proposed model is conducted by comparing its predictions with
the experimental results from multi-level cyclic triaxial tests performed on a
natural loess sampled beside the Northern French railway for high speed train
and about 140 km far from Paris. The comparisons show the capabilities of the
model to describe the behaviour of unsaturated cemented soils under cyclic
loading
In the name of democracy : the value of democracy explains leniency towards wrongdoings as a function of group political organization
According to the "democracy-as-value" hypothesis, democracy has become an ideological belief system providing social value to democratic individuals, groups and institutions, granting legitimacy to their actions (even if dishonest or violent), and protecting them from consecutive punishments. The present research investigates the extent to which this legitimizing process is based on the individual endorsement of democratic principles. Across four experiments, following the misdeed of a (few) group member(s), respondents who valued democratic group organization and democracy in general expressed more lenient retributive justice judgments towards democratic (as compared with nondemocratic) offender groups. These findings shed light on the ways in which democratic ideology infuses justice judgments
Massive lower gastrointestinal bleeding from idiopathic ileocolonic varix: report of a case
Dis Colon Rectum. 2006 Apr;49(4):524-6.
Massive lower gastrointestinal bleeding from idiopathic ileocolonic varix: report of a case.
Lopes LM, Ramada JM, Certo MG, Pereira PR, Soares JM, Ribeiro M, Areias J, Pinho C.
SourceGastroenterology Department, Hospital Geral Santo António, Porto, Portugal. [email protected]
Abstract
Idiopathic varices of the entire colon are very rare. We report on a 64-year-old patient with massive lower gastrointestinal hemorrhage from an extensive ileocolonic varix. Diagnosis was established by colonoscopy. The patient underwent an emergency ileocolectomy with satisfactory results. This rare case shows the importance of colonoscopy in the evaluation of patients with lower gastrointestinal hemorrhage and reminds us that sometimes the diagnosis is not what we expect. Recognition of this abnormality is important because varices may be the cause of massive lower gastrointestinal hemorrhage.
PMID: 16395635 [PubMed - indexed for MEDLINE
Collective punishment depends on collective responsibility and political organization of the target group
What factors determine the willingness to inflict collective punishment upon a group for a misdeed committed by individual group members? This research investigates the effect of collective responsibility shared among group members and the moderating effect of the group's political organization (democratic vs. nondemocratic). Hypothesizing that moral accountability should be greater for democratic offender groups compared to nondemocratic groups, five experiments showed that the positive effect of collective responsibility on support for collective punishment (Experiment 1) was stronger for democratic groups than for nondemocratic groups (Experiments 2-5). A sixth experiment revealed that the moral and social value ascribed to democracy led to higher expectations towards democratic groups, resulting in negative perceptions of the democratic offender group and ultimately in increased collective punishment. The results are discussed in terms of defense strategies of democratic values
PEF treatments of high specific energy permit the reduction of maceration time during vinification of Caladoc and Grenache grapes
Phenolic compounds extracted from the solid parts of the grapes during the maceration-fermentation stage define many of the sensory attributes of red wine such as color, bitterness or astringency. The effect of moderate a PEF treatment (M-PEF) (5 kV·cm-1, 8.8 kJ·kg-1) and an intense PEF treatment (I-PEF) (5 kV·cm-1, 52.9 kJ·kg-1) on the reduction of maceration time during vinification of Caladoc and Grenache grapes was investigated. In both grape varieties, M-PEF treatment combined with 4 days of maceration was the most effective treatment in achieving high anthocyanin content, color intensity and total phenol index at the end of fermentation. The I-PEF treatment promoted a rapid release of anthocyanins and phenolic compounds, along with a fast increment in the color intensity of the must after 24 h of maceration. Although the color intensity and anthocyanin content decreased significantly throughout fermentation when grape pomace was removed after 24 h, these parameters were similar, after 3 months of bottling, in the case of Caladoc and slightly lower in Grenache than the control wine, for which maceration was extended for 10 days. Therefore, results obtained in this investigation are the first to demonstrate the potential of I-PEF for the reduction of maceration time to 24 h in red winemaking
Cultivos de cobertura de invierno como alternativa a barbechos de larga duración en el sudoeste de Buenos Aires
Lejos de los supuestos, los cultivos de cobertura pueden ser una buena opción para sistemas agrícolas bajo secano en regiones donde el agua es el factor que limita la producción.EEA BordenaveFil: de Sa Pereira, Eduardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bordenave. Agencia de Extensión Rural Coronel Suárez; ArgentinaFil: Vechi, G. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentina. Cambio Rural II; ArgentinaFil: Ibarra, C. Buenos Aires (provincia). Ministerio de Asuntos Agrarios; ArgentinaFil: Pedelaborde, J.M. Cambio Rural II; Argentin
Teleparallel Equivalent of Non-Abelian Kaluza-Klein Theory
Based on the equivalence between a gauge theory for the translation group and
general relativity, a teleparallel version of the non-abelian Kaluza-Klein
theory is constructed. In this theory, only the fiber-space turns out to be
higher-dimensional, spacetime being kept always four-dimensional. The resulting
model is a gauge theory that unifies, in the Kaluza-Klein sense, gravitational
and gauge fields. In contrast to the ordinary Kaluza-Klein models, this theory
defines a natural length-scale for the compact sub-manifold of the fiber space,
which is shown to be of the order of the Planck length.Comment: Revtex4, 7 pages, no figures, to appear in Phys. Rev.
Ecotoxicity variation through parabens degradation by single and catalytic ozonation using volcanic rock
Parabens are widely used as antimicrobial and preservative ingredients in pharmaceutical and personal care products. Nevertheless, these compounds have been increasingly seen as emerging contaminants that can be toxic to a wide range of species. In this study, the toxic effect of a mixture of parabens (10 mg/L of each paraben: methyl-, ethyl-, propyl-, benzyl- and butylparaben) and its degradation products through single and catalytic ozonation (using volcanic rock as low-cost catalyst) was investigated over several non-target species: cladocerans, microalgae, clams, macrophytes and cress. The analysis of the toxicity of parabens mixture is relevant since usually these compounds are used as blends rather than individually. While parabens were totally removed both by single and catalytic ozonation the toxicity of the samples resulting from both treatments was generally high. This toxicity was still compared to the one obtained for several dilutions of the initial parabens mixture and it was concluded that the by-products formed are more toxic than the most diluted parabens mixture sample (0.625 mg/L). While catalytic ozonation allows reducing the amount of ozone (about 3-fold) required for total removal of parabens, the resulting treated solution was more toxic than the sample taken at the endpoint of the single ozonation treatment. This suggests that the highest amount of ozone used for single ozonation allowed the elimination of toxic by-products such as hydroquinone and 1,4-benzoquinone. Still, the effect of by-products and parabens interaction depends on the species analyzed due to their different tolerances to potentially toxic products.publishe
Matrix theory of gravitation
A new classical theory of gravitation within the framework of general
relativity is presented. It is based on a matrix formulation of
four-dimensional Riemann-spaces and uses no artificial fields or adjustable
parameters. The geometrical stress-energy tensor is derived from a matrix-trace
Lagrangian, which is not equivalent to the curvature scalar R. To enable a
direct comparison with the Einstein-theory a tetrad formalism is utilized,
which shows similarities to teleparallel gravitation theories, but uses complex
tetrads. Matrix theory might solve a 27-year-old, fundamental problem of those
theories (sec. 4.1). For the standard test cases (PPN scheme,
Schwarzschild-solution) no differences to the Einstein-theory are found.
However, the matrix theory exhibits novel, interesting vacuum solutions.Comment: 24 page
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