447 research outputs found

    Impact of different-sized herbivores on recruitment opportunities for subordinate herbs in grasslands

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    Long-term cross-scale comparison of grazing and mowing on plant diversity and community composition in a salt-marsh system

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    Land abandonment has been increasing in recent decades in Europe, usually accompanied by biodiversity decline. Whether livestock grazing and mowing can safeguard biodiversity across spatial scales in the long term is unclear. Using a 48-year experiment in a salt marsh, we compared land abandonment (without grazing and mowing) and seven management regimes including cattle grazing, early season mowing, late season mowing, both early and late season mowing, and grazing plus each of the mowing regimes on plant diversity at the local and larger scales (i.e. aggregated local communities). Also, we compared their effects on community composition (both in identities and abundances) in time and space. Under land abandonment, plant diversity declined in the local communities and this decline became more apparent at the larger scale, particularly for graminoids and halophytes. All management regimes, except for late season mowing, maintained plant diversity at these scales. Local plant communities under all treatments underwent different successional trajectories, in the end, diverged from their initial state except for that under grazing (a cyclic succession). Year-to-year changes in local community composition remained at a similar level over time under land abandonment and grazing plus early season mowing while it changed under other treatments. Vegetation homogenized at the larger scale over time under land abandonment while vegetation remained heterogeneous under all management regimes. Synthesis. Our experiment suggests that late season mowing may not be sustainable to conserve plant diversity in salt marshes. Other management regimes can maintain plant diversity across spatial scales and vegetation heterogeneity at the larger scale in the long term, but local community composition may change over time.Fil: Chen, Qingqing. University of Groningen; Países BajosFil: Bakker, Jan P.. University of Groningen; Países BajosFil: Alberti, Juan. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Bakker, Elisabeth S.. Netherlands Institute of Ecology; Países Bajos. University of Agriculture Wageningen; Países BajosFil: Smit, Christian. University of Groningen; Países BajosFil: Olff, Han. University of Groningen; Países Bajo

    Contribution of patient registries to regulatory decision making on rare diseases medicinal products in Europe

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    Between 2000 and 2021, the European Medicines Agency (EMA) assigned the orphan designation to over 1,900 medicines. Due to their small target populations, leading to challenges regarding clinical trial recruitment, study design and little knowledge on the natural history of the disease, the overall clinical evidence submitted at the time of marketing authorisation application for these medicines is often limited. Patient registries have been recognised as important sources of data on healthcare practices, drug utilisation and clinical outcomes. They may help address these challenges by providing information on epidemiology, standards of care and treatment patterns of rare diseases. In this review, we illustrate the utility of patient registries across the different stages of development of medicinal products, including orphans, to provide evidence in the context of clinical studies and to generate post-authorisation long term data on their effectiveness and safety profiles. We present important initiatives leveraging the role of registries for orphan medicinal products' development and monitoring to ultimately improve patients' lives

    Brain solute transport is more rapid in periarterial than perivenous spaces

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    Fluid flow in perivascular spaces is recognized as a key component underlying brain transport and clearance. An important open question is how and to what extent differences in vessel type or geometry affect perivascular fluid flow and transport. Using computational modelling in both idealized and image-based geometries, we study and compare fluid flow and solute transport in pial (surface) periarterial and perivenous spaces. Our findings demonstrate that differences in geometry between arterial and venous pial perivascular spaces (PVSs) lead to higher net CSF flow, more rapid tracer transport and earlier arrival times of injected tracers in periarterial spaces compared to perivenous spaces. These findings can explain the experimentally observed rapid appearance of tracers around arteries, and the delayed appearance around veins without the need of a circulation through the parenchyma, but rather by direct transport along the PVSs.publishedVersio

    Вплив структури фонових знань перекладача на інтерпретацію міфологічних алюзій

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    L.M.Chernovaty, T.K.Varenko. An impact of the interpreters’ background knowledge structure upon their interpretation of mythological allusions. Basing upon an experimental research into the ways English sentences containing mythology-related allusions are interpreted into Ukrainian, the author argues for the necessity to include the corresponding elements into the subject-matter of the interpreter-training course to provide for the acquisition of background knowledge in mythology and folklore related to the cultures contacting in the process of interpreting. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/1128

    Liposomes as delivery systems in the prevention and treatment of infectious diseases

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    Research on the potential application of liposomes in the prevention and treatment of infectious diseases has focussed on improvement of the therapeutic index of antimicrobial drugs and immunomodulators and on stimulation of the immune response to otherwise weak antigens in vaccines composed of purified micro-organism subunits. In this review current approaches in this field are outlined. The improved therapeutic index of antimicrobial drugs after encapsulation in liposomes is a result of enhanced drug delivery to infected tissue or infected cells and/or a reduction of drug toxicity of potentially toxic antibiotics. Liposomal encapsulation of immunomodulators that activate macrophages aims at reducing the toxicity of these agents and targeting them to the cells of the mononuclear phagocyte system in order to increase the nonspecific resistance of the host against infections. Studies on the immunogenicity of liposomal antigens have demonstrated that liposomes can potentiate the humoral and cell mediated immunity to a variety of antigens

    Factors Influencing Preferences and Responses Towards Drug Safety Communications:A Conjoint Experiment Among Hospital-Based Healthcare Professionals in the Netherlands

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    Introduction Healthcare professionals (HCPs) are informed about new drug safety issues through Direct Healthcare Professional Communications (DHPCs). The influence of DHPC content on the impact of the communication is unclear. Objectives The aim of this study was to assess the effect of content elements 'frequency of the safety issue', 'seriousness of the safety issue', 'need to take action', 'life span of drug involved' and 'type of evidence supporting the safety issue' on hospital-based HCPs' preferences and responses towards DHPCs. Methods A survey study including a conjoint experiment was performed among hospital-based HCPs in the Netherlands. Hypothetical DHPCs varying on the five content elements were constructed. Each respondent received eight out of 16 hypothetical DHPCs and was asked about (1) importance to be informed (fixed-point scale), (2) preferred communication timing (multiple options) and (3) their stated actions (multiple options). Associations were tested using generalized linear mixed models. Results In total, 178 HCPs participated. DHPCs concerning more frequent or serious safety issues, or requiring action, were associated with a higher perceived importance to be informed and a preference for immediate communication. Periodic communication was preferred for DPHCs concerning less frequent or serious safety issues. The most commonly stated action was to discuss the DHPC with colleagues. Monitoring was common when this was recommended. High frequency and seriousness were associated with more prescribing-related actions. Conclusion Frequency and seriousness of the safety issue and the recommended action are likely to influence the impact of DHPCs. The timing of communication could be tailored depending on the content, where less urgent safety issues might be communicated periodically

    Thermal dosimetry for bladder hyperthermia treatment. An overview.

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    The urinary bladder is a fluid-filled organ. This makes, on the one hand, the internal surface of the bladder wall relatively easy to heat and ensures in most cases a relatively homogeneous temperature distribution; on the other hand the variable volume, organ motion, and moving fluid cause artefacts for most non-invasive thermometry methods, and require additional efforts in planning accurate thermal treatment of bladder cancer. We give an overview of the thermometry methods currently used and investigated for hyperthermia treatments of bladder cancer, and discuss their advantages and disadvantages within the context of the specific disease (muscle-invasive or non-muscle-invasive bladder cancer) and the heating technique used. The role of treatment simulation to determine the thermal dose delivered is also discussed. Generally speaking, invasive measurement methods are more accurate than non-invasive methods, but provide more limited spatial information; therefore, a combination of both is desirable, preferably supplemented by simulations. Current efforts at research and clinical centres continue to improve non-invasive thermometry methods and the reliability of treatment planning and control software. Due to the challenges in measuring temperature across the non-stationary bladder wall and surrounding tissues, more research is needed to increase our knowledge about the penetration depth and typical heating pattern of the various hyperthermia devices, in order to further improve treatments. The ability to better determine the delivered thermal dose will enable clinicians to investigate the optimal treatment parameters, and consequentially, to give better controlled, thus even more reliable and effective, thermal treatments

    Handling of New Drug Safety Information in the Dutch Hospital Setting:A Mixed Methods Approach

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    INTRODUCTION: The implementation of new drug safety information and Direct Healthcare Professional Communications (DHPCs) in hospitals is important for patient safety. OBJECTIVES: The aim of this study was to gain insight into which procedures and practices are in place to handle new drug safety information and particularly DHPCs in the Dutch hospital setting. METHODS: We first conducted focus groups including medical specialists and hospital pharmacists, focusing on handling of drug safety information at the individual and organisational level. A survey was then developed and distributed among hospital pharmacists in all Dutch hospitals to quantify the existence of specific procedures and committees to handle drug safety information and DHPCs. RESULTS: Eleven specialists and 14 pharmacists from six hospitals participated in focus groups. Drug safety information was usually considered before drugs were included in formularies or treatment protocols. Furthermore, drug safety information was consulted in response to patients experiencing adverse events. DHPCs were mostly dealt with by individual professionals. DHPCs could lead to actions but this was very uncommon. Completed surveys were received from 40 (53%) of the hospitals. In 32 (80%), the hospital pharmacy had procedures to deal with new drug safety information, whereas in 11 (28%) a hospital-wide procedure was in place. Drug safety was considered in committees concerning drug formulary decisions (69%) and antibiotic policies (63%). DHPCs were assessed by a hospital pharmacist in 50% of the hospitals. CONCLUSIONS: Drug safety information was used for evaluation of new treatments and in response to adverse events. Assessment of whether a DHPC requires action was primarily an individual task
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