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Objectives: Clinical trials provide one of the highest levels of evidence to support medical practice. Investigator initiated clinical trials (IICTs) answer relevant questions in clinical practice that may not be addressed by industry. For the first time, two European Countries are compared in terms of IICTs, respective funders and publications, envisaging to inspire others to use similar indicators to assess clinical research outcomes. Methods: A retrospective systematic search of registered IICTs from 2004 to 2017, using four clinical trials registries was carried out in two European countries with similar population, GDP, HDI and medical schools but with different governmental models to fund clinical research. Each IICT was screened for sponsors, funders, type of intervention and associated publications, once completed. Results: IICTs involving the Czech Republic and Portugal were n = 439 (42% with hospitals as sponsors) and n = 328 (47% with universities as sponsors), respectively. The Czech Republic and Portuguese funding agencies supported respectively 61 and 27 IICTs. Among these, trials with medicinal products represent 52% in Czech Republic and 4% in Portugal. In the first, a higher percentage of IICTs' publications in high impact factor journals with national investigators as authors was observed, when compared to Portugal (75% vs 15%). Conclusion: The better performance in clinical research by Czech Republic might be related to the existence of specific and periodic funding for clinical research, although further data are still needed to confirm this relationship. In upcoming years, the indicators used herein might be useful to tracking clinical research outcomes in these and other European countries. [ABSTRACT FROM AUTHOR]

We describe the concentration process of a dispersion of silica nanoparticles undergoing evaporation in a dedicated microfluidic device. Using microfocused small-angle X-ray scattering, we measure in time and space both the concentration field of the dispersion and its structure factor. We show that the electrostatic interactions affect the concentration rate by strongly enhancing the collective diffusion coefficient of the nanoparticle dispersion. En route towards high concentrations, the nanoparticles eventually undergo a liquid-solid phase transition in which we evidence crystallites of micron size. [ABSTRACT FROM AUTHOR]

Microporation is an efficient method for delivering plasmid DNA molecules into cultured cells. Herein, we present the optimization of gene delivery by microporation using a Central Composite Design methodology. It was given relevance not only to the transfection efficiency but also to the cell recovery. Different amounts of DNA (1 and 3 μg) mainly affected cell viabilities and cell recoveries, which decrease from 93 to 76% and from 47 to 25% respectively, when higher DNA quantity is used. With this work we suggest an easy methodology to improve transfection of mammalian cells underlining the feasibility to achieve 60% of gene delivery efficiencies whilst recovering 50% of cells, with 90% of viability. [ABSTRACT FROM AUTHOR]

Predator-prey interactions in natural ecosystems generate complex food webs that have a simple universal body-size architecture where predators are systematically larger than their prey. Food-web theory shows that the highest predator-prey body-mass ratios found in natural food webs may be especially important because they create weak interactions with slow dynamics that stabilize communities against perturbations and maintain ecosystem functioning. Identifying these vital interactions in real communities typically requires arduous identification of interactions in complex food webs. Here, we overcome this obstacle by developing predator-trait models to predict average body-mass ratios based on a database comprising 290 food webs from freshwater, marine and terrestrial ecosystems across all continents. We analysed how species traits constrain body-size architecture by changing the slope of the predator-prey body-mass scaling. Across ecosystems, we found high body-mass ratios for predator groups with specific trait combinations including (1) small vertebrates and (2) large swimming or flying predators. Including the metabolic and movement types of predators increased the accuracy of predicting which species are engaged in high body-mass ratio interactions. We demonstrate that species traits explain striking patterns in the body-size architecture of natural food webs that underpin the stability and functioning of ecosystems, paving the way for community-level management of the most complex natural ecosystems.