59 research outputs found

    Graphite oxide as a support for palladium and rhodium complexes, assessed as catalysts for the partial hydrogenation of 1-heptyne

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    Graphite oxide (GO) was used to anchor [PdCl2(TDA)2] and [RhCl(TDA)3] (TDA =NH2(CH2)12CH3) with 2wt % of metal load. Elemental analysis (EA), FTIR, XPS, XRD and atomic absorption spectroscopy (AA) were the techniques employed for characterization. FTIR and XRD revealed that both complexes were mainly immobilized on the GO surface. The partial hydrogenation of 1-heptyne was the test reaction to evaluate the catalytic behavior of these heterogenized complexes under mild conditions of temperature and pressure in a semi continuous process. The results were compared with those obtained with the Wilkinson catalyst under the same operational conditions. AA analysis revealed that there is no leaching of the complexes during the heterogeneous catalytic evaluations. [RhCl(TDA)3]/GO was the best catalyst due to electronic and steric effects as well as the influence of the support

    Management of Dyslipidaemia in Real-world Clinical Practice: Rationale and Design of the VIPFARMA ISCP Project.

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    Dyslipidaemia plays a major role in the pathogenesis of atherosclerosis. Every year, scientific institutions publish cardiovascular prevention guidelines with updated goals and recommendations based on new evidence. However, medical barriers exist that make achieving these goals difficult and gaps between guidelines and best daily clinical practice still persist. The International Society of Cardiovascular Pharmacotherapy designed the Surveillance of Prescription Drugs in the Real World Project (VIPFARMA ISCP), a survey for physicians who manage lipid disorders in high-risk patients. Seven clusters of questions will be analysed comprising demographics, institution profile, access to continuing medical education, clinical practice profile, attitude regarding use of statins, knowledge regarding proprotein convertase subtilisin/kexin type 9 inhibitors and attitudes regarding medical decisions about triglycerides. The present study will be the first part of a larger programme and aims to shed light on barriers between lipid-lowering drug therapy recommendations in the 2019 European Society of Cardiology guidelines and clinical practice in different countries

    Evolution of aerial spider webs coincided with repeated structural optimization of silk anchorages

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    Physical structures built by animals challenge our understanding of biological processes and inspire the development of smart materials and green architecture. It is thus indispensable to understand the drivers, constraints, and dynamics that lead to the emergence and modification of building behavior. Here, we demonstrate that spider web diversification repeatedly followed strikingly similar evolutionary trajectories, guided by physical constraints. We found that the evolution of suspended webs that intercept flying prey coincided with small changes in silk anchoring behavior with considerable effects on the robustness of web attachment. The use of nanofiber based capture threads (cribellate silk) conflicts with the behavioral enhancement of web attachment, and the repeated loss of this trait was frequently followed by physical improvements of web anchor structure. These findings suggest that the evolution of building behavior may be constrained by major physical traits limiting its role in rapid adaptation to a changing environment

    WHF IASC Roadmap on Chagas Disease

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    Background: Chagas Disease is a neglected tropical disease caused by the protozoan Trypanosoma cruzi, with some of the most serious manifestations affecting the cardiovascular system. It is a chronic, stigmatizing condition, closely associated with poverty and affecting close to 6 million people globally. Although historically the disease was limited to endemic areas of Latin America recent years have seen an increasing global spread. In addition to the morbidity and mortality associated with the disease, the social and economic burdens on individuals and society are substantial. Often called the ‘silent killer’, Chagas disease is characterized by a long, asymptomatic phase in affected individuals. Approximately 30% then go on develop chronic Chagas cardiomyopathy and other serious cardiac complications such as stroke, rhythm disturbances and severe heart failure. Methods: In a collaboration of the World Hearth Federation (WHF) and the Inter-American Society of Cardiology (IASC) a writing group consisting of 20 diverse experts on Chagas disease (CD) was convened. The group provided up to date expert knowledge based on their area of expertise. An extensive review of the literature describing obstacles to diagnosis and treatment of CD along with proposed solutions was conducted. A survey was sent to all WHF Members and, using snowball sampling to widen the consultation, to a variety of health care professionals working in the CD global health community. The results were analyzed, open comments were reviewed and consolidated, and the findings were incorporated into this document, thus ensuring a consensus representation. Results: The WHF IASC Roadmap on Chagas Disease offers a comprehensive summary of current knowledge on prevention, diagnosis and management of the disease. In providing an analysis of ‘roadblocks’ in access to comprehensive care for Chagas disease patients, the document serves as a framework from which strategies for implementation such as national plans can be formulated. Several dimensions are considered in the analysis: healthcare system capabilities, governance, financing, community awareness and advocacy. Conclusion: The WHF IASC Roadmap proposes strategies and evidence-based solutions for healthcare professionals, health authorities and governments to help overcome the barriers to comprehensive care for Chagas disease patients. This roadmap describes an ideal patient care pathway, and explores the roadblocks along the way, offering potential solutions based on available research and examples in practice. It represents a call to action to decision-makers and health care professionals to step up efforts to eradicate Chagas disease

    Robust substrate anchorages of silk lines with extensible nano-fibres

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    Living systems are built of multiscale-composites: materials formed of components with different properties that are assembled in complex micro- and nano-structures. Such biological multiscale-composites often show outstanding physical properties that are unachieved by artificial materials. A major scientific goal is thus to understand the assembly processes and the relationship between structure and function in order to reproduce them in a new generation of biomimetic high-performance materials. Here, we tested how the assembly of spider silk nano-fibres (i.e. glue coated 0.5 ÎŒm thick fibres produced by so-called piriform glands) into different micro-structures correlates with mechanical performance by empirically and numerically exploring the mechanical behaviour of line anchors in an orb weaver, a hunting spider and two ancient web builders. We demonstrate that the anchors of orb weavers exhibit outstanding mechanical robustness with minimal material use by the indirect attachment of the silk line to the substrate through a soft domain ('bridge'). This principle can be used to design new artificial high-performance attachment systems

    Fetal visceral maturation : a useful contribution to gestational age estimation in human fetuses.

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    http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=15461089International audienceWith regard to the law, estimating fetal age is essential to assess viability (after 20 weeks according to the WHO) and the proposed methods generally use long bone measurements. Here, we evaluated the accuracy of soft tissue maturational stage and compared it with long bone measurements. First, eight kinds of tissues or organs from 448 fetuses with known medical history were studied (macroscopically or histologically). We clearly demonstrated that adrenal glands and skin were very good age indicators, because some characteristics appeared only after 20 weeks. We established a linear regression with a 95% confidence interval of +/- 2.9 weeks. Second, we applied our original formula using femur measurement and we combined soft tissues and bones in a multiparametric regression. The confidence interval was reduced to +/- 2.5 weeks. We conclude that the pathologist must use both histological and anthropometric data to determine fetal age as accurately as possible
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