689 research outputs found

    Estimating paleogeographic, hydrological and climatic conditions in the upper Burdigalian VallĂšs-PenedĂšs basin (Catalunya, Spain)

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    During the evolution of the VallĂšs-PenedĂšs basin, several transgressive pulses in the upper Burdigalian led to a partial flooding of the western part of the basin, leaving locally sabkha-salina evaporite sediments in the area of the village of VilobĂ­. Due to its geometric configuration with a restricted access to the open sea, deeper marine evaporites do not occur in the basin. A mathematical model of fluid circulation, evaporation outflow, solute transport and evaporite deposition is applied in order to test possible paleogeographic, hydrological and climatic conditions which may have influenced salinity of sea water in the upper Burdigalian VallĂšs-PenedĂšs embayment. Simulation results indicate that the absence of marine gypsum sediments in the basin may be related to a significant freshwater supply. The shift from the Neogene basin drainage pattern along the complete basin axis with elevated freshwater discharge to the river drainage towards the Barcelona area occurred at later stages of the basin evolution

    Kick-starting GPLVM Optimization via a Connection to Metric MDS

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    The Gaussian Process Latent Variable Model (GPLVM) is an attractive model for dimensionality reduction, but the optimization of the GPLVM likelihood with respect to the latent point locations is difficult, and prone to local optima. Here we start from the insight that in the GPLVM, we should have that , where is the kernel function evaluated at latent points and , and is the corresponding estimate from the data. For an isotropic covariance function this relationship can be inverted to yield an estimate of the interpoint distances in the latent space, and these can be fed into a multidimensional scaling (MDS) algorithm. This yields an initial estimate of the latent locations, which can be subsequently optimized in the usual GPLVM fashion. We compare two variants of this approach to the standard PCA initialization and to the ISOMAP algorithm, and show that our initialization converges to the best GPLVM likelihoods on all six tested motion capture data sets

    SIMSAFADIM-CLASTIC : a new approach to mathematical 3D forward simulation modelling for terrigenous and carbonate marine sedimentation

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    Most sedimentary modelling programs developed in recent years focus on either terrigenous or carbonate marine sedimentation. Nevertheless, only a few programs have attempted to consider mixed terrigenous-carbonate sedimentation, and most of these are two-dimensional, which is a major restriction since geological processes take place in 3D. This paper presents the basic concepts of a new 3D mathematical forward simulation model for clastic sediments, which was developed from SIMSAFADIM, a previous 3D carbonate sedimentation model. The new extended model, SIMSAFADIM-CLASTIC, simulates processes of autochthonous marine carbonate production and accumulation, together with clastic transport and sedimentation in three dimensions of both carbonate and terrigenous sediments. Other models and modelling strategies may also provide realistic and efficient tools for prediction of stratigraphic architecture and facies distribution of sedimentary deposits. However, SIMSAFADIM-CLASTIC becomes an innovative model that attempts to simulate different sediment types using a process-based approach, therefore being a useful tool for 3D prediction of stratigraphic architecture and facies distribution in sedimentary basins. This model is applied to the neogene VallĂšs-PenedĂšs half-graben (western Mediterranean, NE Spain) to show the capacity of the program when applied to a realistic geologic situation involving interactions between terrigenous clastics and carbonate sediments

    Spinal anaesthesia in a patient with Takayasu's disease

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    We report the successful anaesthetic management of therapeutic abortion under spinal anaesthesia in a 32-yr-old woman with Takayasu's disease. The pathology and pathophysiology of this syndrome and their impact on anaesthesia are discussed. (Br. J. Anaesth. 1994; 72: 129-132

    Experimental Evidence for the Incorporation of Two Metals at Equivalent Lattice Positions in Mixed-Metal Metal–Organic Frameworks

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    Metal–organic frameworks containing multiple metals distributed over crystallographically equivalent framework positions (mixed‐metal MOFs) represent an interesting class of materials, since the close vicinity of isolated metal centers often gives rise to synergistic effects. However, appropriate characterization techniques for detailed investigations of these mixed‐metal metal–organic framework materials, particularly addressing the distribution of metals within the lattice, are rarely available. The synthesis of mixed‐metal FeCuBTC materials in direct syntheses proved to be difficult and only a thorough characterization using various techniques, like powder X‐ray diffraction, X‐ray absorption spectroscopy and electron paramagnetic resonance spectroscopy, unambiguously evidenced the formation of a mixed‐metal FeCuBTC material with HKUST‐1 structure, which contained bimetallic Fe−Cu paddlewheels as well as monometallic Cu−Cu and Fe−Fe units under optimized synthesis conditions. The in‐depth characterization showed that other synthetic procedures led to impurities, which contained the majority of the applied iron and were impossible or difficult to identify using solely standard characterization techniques. Therefore, this study shows the necessity to characterize mixed‐metal MOFs extensively to unambiguously prove the incorporation of both metals at the desired positions. The controlled positioning of metal centers in mixed‐metal metal–organic framework materials and the thorough characterization thereof is particularly important to derive structure–property or structure–activity correlations

    Post-synthetic Modification of DUT-5-based Metal Organic Frameworks for the Generation of Single-site Catalysts and their Application in Selective Epoxidation Reactions

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    New single‐site catalysts based on mixed‐linker metal‐organic frameworks with DUT‐5 structure, which contain immobilized Co2+, Mn2+ and Mn3+ complexes, have successfully been synthesized via post‐synthetic modification. 2,2’‐Bipyridine‐5,5’‐dicarboxylate linkers were directly metalated, while 2‐amino‐4,4’‐biphenyldicarboxylate linkers were post‐synthetically modified by their conversion to Schiff‐base ligands and a subsequent immobilization of the metal complexes. The resulting materials were used as catalysts in the selective epoxidation of trans‐stilbene and the activities and selectivities of the different catalysts were compared. The influence of various reaction parameters on conversion, yield and selectivity were investigated. Very low catalyst amounts of 0.02 mol % were sufficient to obtain a high conversion of trans‐stilbene using molecular oxygen from air as the oxidant. For cobalt‐containing MOF catalysts, conversions up to 90 % were observed and, thus, they were more active than their manganese‐containing counterparts. Recycling experiments and hot filtration tests proved that the reactions were mainly catalyzed via heterogeneous pathways

    How do women prepare for pregnancy? Preconception experiences of women attending antenatal services and views of health professionals

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    Copyright: © 2014 Stephenson et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Main objective - To determine the extent to which women plan and prepare for pregnancy. Methods - Cross-sectional questionnaire survey of pregnant women attending three maternity services in London about knowledge and uptake of preconception care; including a robust measure of pregnancy planning, and phone interviews with a range of health care professionals. Main results - We recruited 1173/1288 (90%) women, median age of 32 years. 73% had clearly planned their pregnancy, 24% were ambivalent and only 3% of pregnancies were unplanned. 51% of all women and 63% of those with a planned pregnancy took folic acid before pregnancy. 21% of all women reported smoking and 61% reported drinking alcohol in the 3 months before pregnancy; 48% of smokers and 41% of drinkers reduced or stopped before pregnancy. The 51% of all women who reported advice from a health professional before becoming pregnant were more likely to adopt healthier behaviours before pregnancy [adjusted odds ratios for greatest health professional input compared with none were 2.34 (95% confidence interval 1.54–3.54) for taking folic acid and 2.18 (95% CI 1.42–3.36) for adopting a healthier diet before pregnancy]. Interviews with 20 health professionals indicated low awareness of preconception health issues, missed opportunities and confusion about responsibility for delivery of preconception care. Significance of the findings - Despite a high level of pregnancy planning, awareness of preconception health among women and health professionals is low, and responsibility for providing preconception care is unclear. However, many women are motivated to adopt healthier behaviours in the preconception period, as indicated by halving of reported smoking rates in this study. The link between health professional input and healthy behaviour change before pregnancy is a new finding that should invigorate strategies to improve awareness and uptake of pre-pregnancy health care, and bring wider benefits for public health.Department of Healt

    A type VII-secreted lipase toxin with reverse domain arrangement

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    Funding: This study was supported by the Wellcome Trust (through Investigator Awards 10183/Z/15/Z and 224151/Z/21/Z to TP), the Intramural Research Program of the NIH, NCI, Center for Cancer Research (awarded to SML), the German Centre of Infection Research (DZIF) to SH (TTU 08.708). NM holds a Walter Benjamin Fellowship (M2871/1-1), funded by the DFG (German Research Foundation). Additionally, we acknowledge infrastructural funding by the DFG in the frame of Germany's Excellence Strategy—EXC 2124—390838134 (SH). SG is funded by the Newcastle-Liverpool-Durham BBSRC DTP2 Training Grant, project reference number BB/M011186/1 and YY by the China Scholarship Council.The type VII protein secretion system (T7SS) is found in many Gram-positive bacteria and in pathogenic mycobacteria. All T7SS substrate proteins described to date share a common helical domain architecture at the N-terminus that typically interacts with other helical partner proteins, forming a composite signal sequence for targeting to the T7SS. The C-terminal domains are functionally diverse and in Gram-positive bacteria such as Staphylococcus aureus often specify toxic anti-bacterial activity. Here we describe the first example of a class of T7 substrate, TslA, that has a reverse domain organisation. TslA is widely found across Bacillota including Staphylococcus, Enterococcus and Listeria. We show that the S. aureus TslA N-terminal domain is a phospholipase A with anti-staphylococcal activity that is neutralised by the immunity lipoprotein TilA. Two small helical partner proteins, TlaA1 and TlaA2 are essential for T7-dependent secretion of TslA and at least one of these interacts with the TslA C-terminal domain to form a helical stack. Cryo-EM analysis of purified TslA complexes indicate that they share structural similarity with canonical T7 substrates. Our findings suggest that the T7SS has the capacity to recognise a secretion signal present at either end of a substrate.Publisher PDFPeer reviewe

    Draft genome sequences of Pseudomonas fluorescens strains SF39a and SF4c, potential plant growth promotion and biocontrol agents

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    Pseudomonas fluorescens SF4c and SF39a, strains isolated from wheat rhizosphere, have potential applications in plant growth promotion and biocontrol of fungal diseases of crop plants. We report the draft genome sequences of SF4c and SF39a with estimated sizes of 6.5 Mb and 5.9 Mb, respectively.Fil: Ly, Lindsey K.. University of Massachussets; Estados UnidosFil: Underwood, Grace E.. University of Massachussets; Estados UnidosFil: McCully, Lucy M.. University of Massachussets; Estados UnidosFil: Bitzer, Adam S.. University of Massachussets; Estados UnidosFil: Godino, Agustina. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - CĂłrdoba; Argentina. Universidad Nacional de RĂ­o Cuarto. Facultad de Ciencias Exactas, FisicoquĂ­micas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Bucci, Vanni. University of Massachussets; Estados UnidosFil: Brigham, Christopher J.. University of Massachussets; Estados UnidosFil: Principe, Analia. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - CĂłrdoba; Argentina. Universidad Nacional de RĂ­o Cuarto. Facultad de Ciencias Exactas, FisicoquĂ­micas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Fischer, Sonia Elizabeth. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - CĂłrdoba; Argentina. Universidad Nacional de RĂ­o Cuarto. Facultad de Ciencias Exactas, FisicoquĂ­micas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Silby, Mark W.. University of Massachussets; Estados Unido
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