407 research outputs found

    L'evolution du cortege des mineraux argileux dans la sedimentation marine neogene du bassin occidental du Guadalquivir (Espagne du s.o.)

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    La depresión neógena de sedimentación marina del Bajo Guadalquivir resulta del hundimiento del zócalo durante el Mioceno final. En cuanto se asienta dicha depresión, está ocupada en su mayor parte por el manto de corrimiento submarino de Carmona, que la parte en tres "subestructuras": una depresión S. en el área subbética, una cúpula central al S y al SE de Sevilla, un surco N en el borde del Paleozoicode la Meseta ibérica.En las dos primeras, la sedimentación arcillosa se caracteriza por la abundancia de la montmorillonita. En la última, los minerales arcillosos predominantes siguen una evolución cíclica vertical : Montmorillonita - Illita - Kaolinita + Chlorita - Illita - Montmorillonita, interpretada mediante el acarreo de dos clases de materiales detríticos finos: - procedentes directamente de los continentes limítrofes de clima caluroso y de estaciones contrastadas, en cuanto a la abundancia de la Montmorillonita; - procedentes del mar, desde regiones más o menos próximas, de clima caluroso más húmedo, en cuanto a los sedimentos,entre los cuales predominan Iillita, Kaolinita y Chlorita.Por otra parte, los valores elevados de dichos minerales muestran que a fines del Mioceno superior II y a principios del Plioceno, el surco norte bético se abre a las influencias marinas, quedándose fuera del control continental de sedimentación durante ese corto período

    Melanoma and Pregnancy

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    L'evolution du cortege des mineraux argileux dans la sedimentation marine neogene du bassin occidental du Guadalquivir (Espagne du s.o.)

    Get PDF
    La depresión neógena de sedimentación marina del Bajo Guadalquivir resulta del hundimiento del zócalo durante el Mioceno final. En cuanto se asienta dicha depresión, está ocupada en su mayor parte por el manto de corrimiento submarino de Carmona, que la parte en tres "subestructuras": una depresión S. en el área subbética, una cúpula central al S y al SE de Sevilla, un surco N en el borde del Paleozoicode la Meseta ibérica.En las dos primeras, la sedimentación arcillosa se caracteriza por la abundancia de la montmorillonita. En la última, los minerales arcillosos predominantes siguen una evolución cíclica vertical : Montmorillonita - Illita - Kaolinita + Chlorita - Illita - Montmorillonita, interpretada mediante el acarreo de dos clases de materiales detríticos finos: - procedentes directamente de los continentes limítrofes de clima caluroso y de estaciones contrastadas, en cuanto a la abundancia de la Montmorillonita; - procedentes del mar, desde regiones más o menos próximas, de clima caluroso más húmedo, en cuanto a los sedimentos,entre los cuales predominan Iillita, Kaolinita y Chlorita.Por otra parte, los valores elevados de dichos minerales muestran que a fines del Mioceno superior II y a principios del Plioceno, el surco norte bético se abre a las influencias marinas, quedándose fuera del control continental de sedimentación durante ese corto período

    Microstructural Characterization of Graphite Spheroids in Ductile Iron

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    The present work brings new insights by transmission electron microscopy allowing disregarding or supporting some of the models proposed for spheroidal growth of graphite in cast irons. Nodules consist of sectors made of graphite plates elongated along a hai direction and stack on each other with their c axis aligned with the radial direction. These plates are the elementary units for spheroidal growth and a calculation supports the idea that new units continuously nucleate at the ledge between sectors

    Early warning of critical transitions in biodiversity from compositional disorder

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    Global environmental change presents a clear need for improved leading indicators of critical transitions, especially those that can be generated from compositional data and that work in empirical cases. Ecological theory of community dynamics under environmental forcing predicts an early replacement of slowly replicating and weakly competitive “canary” species by slowly replicating but strongly competitive “keystone” species. Further forcing leads to the eventual collapse of the keystone species as they are replaced by weakly competitive but fast‐replicating “weedy” species in a critical transition to a significantly different state. We identify a diagnostic signal of these changes in the coefficients of a correlation between compositional disorder and biodiversity. Compositional disorder measures unpredictability in the composition of a community, while biodiversity measures the amount of species in the community. In a stochastic simulation, sequential correlations over time switch from positive to negative as keystones prevail over canaries, and back to positive with domination of weedy species. The model finds support in empirical tests on multi‐decadal time series of fossil diatom and chironomid communities from lakes in China. The characteristic switch from positive to negative correlation coefficients occurs for both communities up to three decades preceding a critical transition to a sustained alternate state. This signal is robust to unequal time increments that beset the identification of early‐warning signals from other metrics

    Long-Term Impact of Cyclosporin Reduction with MMF Treatment in Chronic Allograft Dysfunction: REFERENECE Study 3-Year Follow Up

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    Calcineurin inhibitor (CNI) toxicity contributes to chronic allograft nephropathy (CAN). In the 2-year, randomized, study, we showed that 50% cyclosporin (CsA) reduction in combination with mycophenolate mofetil (MMF) treatment improves kidney function without increasing the risk for graft rejection/loss. To investigate the long-term effect of this regimen, we conducted a follow up study in 70 kidney transplant patients until 5 years after REFERENCE initiation. The improvement of kidney function was confirmed in the MMF group but not in the control group (CsA group). Four graft losses occurred, 2 in each group (graft survival in the MMF group 95.8% and 90.9% in control group). One death occurred in the control group. There was no statistically significant difference in the occurrence of serious adverse events or acute graft rejections. A limitation is the weak proportion of patient still remaining within the control group. On the other hand, REFERENCE focuses on the CsA regimen while opinions about the tacrolimus ones are still debated. In conclusion, CsA reduction in the presence of MMF treatment seems to maintain kidney function and is well tolerated in the long term

    Improving strength grading of lumber by grain angle measurement and mechanical modeling

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    Timber strength grading has become a major issue in the European Union during the last years, due to the introduction of the Eurocode 5 and all its related standards. Currently, the most performing strength grading machines are able to locally detect the boards’ knots sizes and positions and interpret this information through adapted grading models. The best lead to improve their accuracy seems to be the introduction of new information about the boards and adapt the mechanical model to take them in account. Small grain angle causes high reduction of clear wood’s mechanical properties, local value of slope of grain appears to be of high interest. The aim of this study is to quantify the additionalaccuracy that grain angle information can bring toan optical scanner used as a strength grading machine. A specific grading model has been developed accordingly, and the results obtained for different machine / model / loading combinations are presented. These results show that slope of grain measurement can significantly improve the accuracy of the optical scanner, for both MOE and MOR estimations.ANR ClaMe

    Expression of Foxp3 in colorectal cancer but not in Treg cells correlates with disease progression in patients with colorectal cancer

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    Background: Regulatory T cells (Treg) expressing the transcription factor forkhead-box protein P3 (Foxp3) have been identified to counteract anti-tumor immune responses during tumor progression. Besides, Foxp3 presentation by cancer cells itself may also allow them to evade from effector T-cell responses, resulting in a survival benefit of the tumor. For colorectal cancer (CRC) the clinical relevance of Foxp3 has not been evaluated in detail. Therefore the aim of this study was to study its impact in colorectal cancer (CRC). Methods and Findings: Gene and protein analysis of tumor tissues from patients with CRC was performed to quantify the expression of Foxp3 in tumor infiltrating Treg and colon cancer cells. The results were correlated with clinicopathological parameters and patients overall survival. Serial morphological analysis demonstrated Foxp3 to be expressed in cancer cells. High Foxp3 expression of the cancer cells was associated with poor prognosis compared to patients with low Foxp3 expression. In contrast, low and high Foxp3 level in tumor infiltrating Treg cells demonstrated no significant differences in overall patient survival. Conclusions: Our findings strongly suggest that Foxp3 expression mediated by cancer cells rather than by Treg cells contribute to disease progression
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