679 research outputs found

    Modelling phase-assemblage diagrams for magnesian metapelites in the system K2O-FeO-MgO-Al2O3-SiO2-H2O: geodynamic consequences for the Monte Rosa nappe, Western Alps

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    Magnesian metamorphic rocks with metapelitic mineral assemblage and composition are of great interest in metamorphic petrology for their ability to constrain P-T conditions in terranes where metamorphism is not easily visible. Phase-assemblage diagrams for natural and model magnesian metapelites in the system KFMASH are presented to document how phase relationships respond to water activity, bulk composition, pressure and temperature. The phase assemblages displayed on these phase diagrams are consistent with natural mineral assemblages occurring in magnesian metapelites. It is shown that the equilibrium assemblages at high pressure conditions are very sensitive to a(H2O). Specifically, the appearance of the characteristic HP assemblage chloritoid-talc-phengite-quartz (with excess H2O) in the magnesian metapelites of the Monte Rosa nappe (Western Alps) is due to the reduction of a(H2O). Furthermore, the mineral assemblages are determined by the whole-rock FeO/(FeO+MgO) ratio and effective Al content X A as well as P and T. The predicted mineral associations for the low- and high-X A model bulk compositions of magnesian metapelites at high pressure are not dependent on the X A variations as they show a similar sequence of mineral assemblages. Above 20kbar, the prograde sequence of assemblages associated with phengite (with excess SiO2 and H2O) for low- and high-X A bulk compositions of magnesian metapelites is: carpholite-chlorite→chlorite-chloritoid→chloritoid-talc→chloritoid-talc-kyanite→ talc-garnet-kyanite→garnet-kyanite±biotite. At low to medium P-T conditions, a low-X A stabilises the phengite-bearing assemblages associated with chlorite, chlorite+K-feldspar and chlorite+biotite while a high-X A results in the chlorite-phengite bearing assemblages associated with pyrophyllite, andalusite, kyanite and carpholite. A high-X A magnesian metapelite with nearly iron-free content stabilises the talc-kyanite-phengite assemblage at moderate to high P-T conditions. Taking into account the effective bulk composition and a(H2O) involved in the metamorphic history, the phase-assemblage diagrams presented here may be applied to all magnesian metapelites that have compositions within the system KFMASH and therefore may contribute to gaining insights into the metamorphic evolution of terranes. As an example, the magnesian metapelites of the Monte Rosa nappe have been investigated, and an exhumation path with P-T conditions for the western roof of the Monte Rosa nappe has been derived for the first time. The exhumation shows first a near-isothermal decompression from the Alpine eclogite peak conditions around 24kbar and 505°C down to approximately 8kbar and 475°C followed by a second decompression with concomitant coolin

    Impact of short-acting vs. standard anaesthetic agents on obstructive sleep apnoea: a randomised, controlled, triple-blind trial.

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    Sleep apnoea is associated with negative outcomes following general anaesthesia. Current recommendations suggest using short-acting anaesthetic agents in preference to standard agents to reduce this risk, but there is currently no evidence to support this. This randomised controlled triple-blind trial tested the hypothesis that a combination of short-acting agents (desflurane-remifentanil) would reduce the postoperative impact of general anaesthesia on sleep apnoea severity compared with standard agents (sevoflurane-fentanyl). Sixty patients undergoing hip arthroplasty under general anaesthesia were randomised to anaesthesia with desflurane-remifentanil or sevoflurane-fentanyl. Respiratory polygraphy was performed before surgery and on the first and third postoperative nights. The primary outcome was the supine apnoea-hypopnoea index on the first postoperative night. Secondary outcomes were the supine apnoea-hypopnoea index on the third postoperative night, and the oxygen desaturation index on the first and third postoperative nights. Additional outcomes included intravenous morphine equivalent consumption and pain scores on postoperative days 1, 2 and 3. Pre-operative sleep study data were similar between groups. Mean (95%CI) values for the supine apnoea-hypopnoea index on the first postoperative night were 18.9 (12.7-25.0) and 21.4 (14.2-28.7) events.h <sup>-1</sup> , respectively, in the short-acting and standard anaesthesia groups (p = 0.64). Corresponding values on the third postoperative night were 28.1 (15.8-40.3) and 38.0 (18.3-57.6) events.h <sup>-1</sup> (p = 0.34). Secondary sleep- and pain-related outcomes were generally similar in the two groups. In conclusion, short-acting anaesthetic agents did not reduce the impact of general anaesthesia on sleep apnoea severity compared with standard agents. These data should prompt an update of current recommendations

    Induction of distinct plant cell death programs by secreted proteins from the wheat pathogen Zymoseptoria tritici

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    Cell death processes in eukaryotes shape normal development and responses to the environment. For plant–microbe interactions, initiation of host cell death plays an important role in determining disease outcomes. Cell death pathways are frequently initiated following detection of pathogen-derived molecules which can lead to resistance or susceptibility to disease depending on pathogen lifestyle. We previously identified several small secreted proteins (SSPs) from the wheat-infecting fungus Zymoseptoria tritici that induce rapid cell death in Nicotiana benthamiana following Agrobacterium-mediated delivery and expression (agroinfiltration). Here we investigated whether the execution of host cells was mechanistically similar in response to different Z. tritici SSPs. Using RNA sequencing, we found that transient expression of four Z. tritici SSPs led to massive transcriptional reprogramming within 48 h of agroinfiltration. We observed that distinct host gene expression profiles were induced dependent on whether cell death occurs in a cell surface immune receptor-dependent or -independent manner. These gene expression profiles involved differential transcriptional networks mediated by WRKY, NAC and MYB transcription factors. In addition, differential expression of genes belonging to different classes of receptor-like proteins and receptor-like kinases was observed. These data suggest that different Z. tritici SSPs trigger differential transcriptional reprogramming in plant cells

    Pain during injections of botulinum toxin in children: Influence of the localization technique

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    Objective In this study, we consider two localization techniques used in injections of botulinium toxin in children: electrical stimulation and ultrasound. The hypothesis of this work was that injections performed without stimulation would be less painful. Patients and methods Monocentric prospective study, with 107 sessions of lower limb injections. Two groups of children were compared: localization by ultrasound only (60 children), detection by stimulation only or by stimulation combined with ultrasound (47 children). Pain assessment was performed by the child or an accompanying party using the Visual Analog Scale (VAS) and by a health care team using the Face, Legs, Activity, Cry, Consolability (FLACC). Results A significant difference between the two groups was found in both self-report and by means of the behavioral observational pain scale. Indeed, VAS average and FLACC average were significantly higher with detection by stimulation than with ultrasound alone: 4.5 cm ± 2.54 versus 2.7 cm ± 2.27; P < 0.001 for VAS scale and 3.7 ± 2.1 versus 2.7 ± 2.3; P < 0.05 for FLACC scale. Conclusion When compared to ultrasound detection, localization by electrostimulation appears to increase the overall pain caused during injections of botulinum toxin in children

    Plan de acción frente al consumismo global de la Nueva Economía: Revelaciones sobre economía, empresa y consumo del s. XXI

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    Este estudio crítico y revisionista, de corte interdisciplinario (entre Humanidades y Ciencias Sociales), alerta sobre los peligros de avanzar hacia una sociedad masa global de consumo, donde se acentúe la deshumanización y asocialización, al primarse el tener al ser (el bienestar a la felicidad, el negocio al ocio, la empresa al oficio, la pulsión a la experiencia, etc.). Se ofrece así un plan de acción que va de lo más general (retirando los velos de confusión que impiden reconocer el mundo posglobalizado y estudiarlo tal como es), pasando a centrar la atención en las complejas reglas económicas y empresariales del nuevo milenio, para terminar evaluando los riesgos de la inautenticidad del actual consumidor.This is a critical and reviewer study, under an interdisciplinary approach (between Liberal Arts and Social Sciences), which warns to move on a global mass consumer society and its dangers, by the accentuated lost of humanity and sociality, because the priority of the having-issue than the been-issue (the preference of welfare than happiness, the business than the recreation, the company than the profession, the desire than the experience, etc.). The structure of the paper goes from general view (removing the confusion veils that make impossible the recognition of the post-globalized World and its study), to particular view (focusing on the complex economic and business rules in the new millennium), and the risk evaluation of the non-authenticity of the current consumer
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