22 research outputs found

    Selfsimilar Domain Growth, Localized Structures and Labyrinthine Patterns in Vectorial Kerr Resonators

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    We study domain growth in a nonlinear optical system useful to explore different scenarios that might occur in systems which do not relax to thermodynamic equilibrium. Domains correspond to equivalent states of different circular polarization of light. We describe three dynamical regimes: a coarsening regime in which dynamical scaling holds with a growth law dictated by curvature effects, a regime in which localized structures form, and a regime in which polarization domain walls are modulationally unstable and the system freezes in a labyrinthine pattern.Comment: 13 pages, 6 figure

    Novel rhodium on carbon catalysts for the oxidation of benzyl alcohol to benzaldehyde: A study of the modification of metal/support interactions by acid pre-treatments

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    Rhodium nanoparticles or rhodium organometallic complexes are mainly used in catalysis for reduction or hydroformylation reactions. In this work instead, we explored the capabilities of Rh nanoparticles as an oxidation catalyst, applied to the oxidation of benzyl alcohol to benzaldehyde under very mild conditions (100 °C, and atmospheric pressure) as a model reaction. Here we report the preparation of novel Rh/C catalysts by using an impregnation protocol, with particular emphasis on the pre-treatment of the carbon supports by using HNO3 and HCl, as well as the characterization of these materials by using an array of methods involving TEM, XPS and XRPD. Our preparation method led to a wide Rh particle size distribution ranging from 20 to 100 nm, and we estimate an upper limit diameter of Rh nanoparticles for their activity towards benzyl alcohol oxidation to be ca. 30 nm. Furthermore, a HNO3 pre-treatment of the activated carbon support was able to induce a smaller and narrower particle size distribution of Rh nanoparticles, whereas a HCl pre-treatment had no effect or sintered the Rh nanoparticles. We rationalise these results by HNO3 as an acid able to create new nucleation sites for Rh on the carbon surface, with the final effect of smaller nanoparticles, whereas for HCl the effect of sintering was most likely due to site blocking of the nucleation sites over the carbon surface. The roles of acid centres on the carbon surfaces for the oxidation reaction was also investigated, and the larger their amounts the larger the amounts of by-products. However, by treatment with HNO3 we were able to convert neutral or basic carbons into supports capable to enhance the catalytic activity of Rh, and yet minimised detrimental effects on the selectivity of the oxidation to benzaldehyde

    A recurrent de novo MAX p.Arg60Gln variant causes a syndromic overgrowth disorder through differential expression of c-Myc target genes

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    Cyclin D2 (CCND2) stabilization underpins a range of macrocephaly-associated disorders through mutation of CCND2 or activating mutations in upstream genes encoding PI3K-AKT pathway components. Here, we describe three individuals with overlapping macrocephaly-associated phenotypes who carry the same recurrent de novo c.179G>A (p.Arg60Gln) variant in Myc-associated factor X (MAX). The mutation, located in the b-HLH-LZ domain, causes increased intracellular CCND2 through increased transcription but it does not cause stabilization of CCND2. We show that the purified b-HLH-LZ domain of MAXArg60Gln (Max∗Arg60Gln) binds its target E-box sequence with a lower apparent affinity. This leads to a more efficient heterodimerization with c-Myc resulting in an increase in transcriptional activity of c-Myc in individuals carrying this mutation. The recent development of Omomyc-CPP, a cell-penetrating b-HLH-LZ-domain c-Myc inhibitor, provides a possible therapeutic option for MAXArg60Gln individuals, and others carrying similar germline mutations resulting in dysregulated transcriptional c-Myc activity

    Monitoring of Farm-Level Antimicrobial Use to Guide Stewardship: Overview of Existing Systems and Analysis of Key Components and Processes

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    peer-reviewedThe acknowledgment of antimicrobial resistance (AMR) as a major health challenge in humans, animals and plants, has led to increased efforts to reduce antimicrobial use (AMU). To better understand factors influencing AMR and implement and evaluate stewardship measures for reducing AMU, it is important to have sufficiently detailed information on the quantity of AMU, preferably at the level of the user (farmer, veterinarian) and/or prescriber or provider (veterinarian, feed mill). Recently, several countries have established or are developing systems for monitoring AMU in animals. The aim of this publication is to provide an overview of known systems for monitoring AMU at farm-level, with a descriptive analysis of their key components and processes. As of March 2020, 38 active farm-level AMU monitoring systems from 16 countries were identified. These systems differ in many ways, including which data are collected, the type of analyses conducted and their respective output. At the same time, they share key components (data collection, analysis, benchmarking, and reporting), resulting in similar challenges to be faced with similar decisions to be made. Suggestions are provided with respect to the different components and important aspects of various data types and methods are discussed. This overview should provide support for establishing or working with such a system and could lead to a better implementation of stewardship actions and a more uniform communication about and understanding of AMU data at farm-level. Harmonization of methods and processes could lead to an improved comparability of outcomes and less confusion when interpreting results across systems. However, it is important to note that the development of systems also depends on specific local needs, resources and aims

    A de novo 3.57 Mb microdeletion in 8q12.3q13.2 in a patient with mild intellectual disability and epilepsy.

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    Item does not contain fulltextA female patient, nine years of age, is reported with a history characterized by delay of psychomotor and speech development, mild to moderate intellectual disability and persistent sleep disturbances since the age of two. The patient showed facial dysmorphisms, a pectus excavatum and a sandal gap. Apart from lowered intelligence, neuropsychological functioning disclosed impaired attentional capacities and executive control as well as weak motor skills. Genome wide SNP array analysis revealed a 3.57 Mb de novo microdeletion in band q12.3 of chromosome 8. The long lasting sleep disorders turned out to originate from a rare juvenile epilepsy, continuous spike-waves during slow sleep (CSWS) syndrome, that includes the electrical status epilepticus in sleep (ESES) phenomenon. MRI-scanning of the brain showed no abnormalities. To the authors knowledge, this is the first report of a de novo 8q12.3q13.2 microdeletion syndrome that presents with ESES/CSWS.01 mei 201

    Monitoring of Farm-Level Antimicrobial Use to Guide Stewardship: Overview of Existing Systems and Analysis of Key Components and Processes

    Get PDF
    The acknowledgment of antimicrobial resistance (AMR) as a major health challenge in humans, animals and plants, has led to increased efforts to reduce antimicrobial use (AMU). To better understand factors influencing AMR and implement and evaluate stewardship measures for reducing AMU, it is important to have sufficiently detailed information on the quantity of AMU, preferably at the level of the user (farmer, veterinarian) and/or prescriber or provider (veterinarian, feed mill). Recently, several countries have established or are developing systems for monitoring AMU in animals. The aim of this publication is to provide an overview of known systems for monitoring AMU at farm-level, with a descriptive analysis of their key components and processes. As of March 2020, 38 active farm-level AMU monitoring systems from 16 countries were identified. These systems differ in many ways, including which data are collected, the type of analyses conducted and their respective output. At the same time, they share key components (data collection, analysis, benchmarking, and reporting), resulting in similar challenges to be faced with similar decisions to be made. Suggestions are provided with respect to the different components and important aspects of various data types and methods are discussed. This overview should provide support for establishing or working with such a system and could lead to a better implementation of stewardship actions and a more uniform communication about and understanding of AMU data at farm-level. Harmonization of methods and processes could lead to an improved comparability of outcomes and less confusion when interpreting results across systems. However, it is important to note that the development of systems also depends on specific local needs, resources and aims
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