1,697 research outputs found
Closing the Procurement Gap. The costly failure to mobilise sustainable procurement for innovation. A Provocation written as a background paper for the discussion forum at Business Innovation and Skills.
Evaluating the demand side: New challenges for evaluation
Evaluation of research and innovation policy faces radical challenges arising from a new policy emphasis upon demand-side measures and linked to this an understanding of innovation policy as a means to achieve societal goals. This article considers the implications for the practice of evaluation at both micro and meso-levels. It uses the exemplar of an evaluation design for the European Union's Lead Market Initiative to expose the extent to which classical approaches to evaluation are valid and where new issues arise. Some problems highlighted include the difficulty of establishing a relevant baseline, the inability of public statistics constructed in supply-side mode to capture actions, the need to engage with actors who do not necessarily see themselves as part of the initiative being evaluated, long timescales and potential wide geographical scope, measures that span from micro to macro, and blurred boundaries between implementation and impact. It is concluded that there is a key role for evaluators to become involved in co-learning and co-evolution of these policy instruments in a manner analogous to the relationship between evaluation and policy development that characterized the emergence of collaborative R&D support programmes
Anomalous buoyancy of quantum bubbles in immiscible Bose mixtures
Buoyancy is a well-known effect in immiscible binary Bose-Einstein
condensates. Depending on the differential confinement experienced by the two
components, a bubble of one component sitting at the center of the other
eventually floats to the surface, around which it spreads either totally or
partially. We discuss how quantum fluctuations may significantly change the
volume and position of immiscible bubbles. We consider the particular case of
two miscible components, forming a pseudo-scalar bubble condensate with
enhanced quantum fluctuations (quantum bubble), immersed in a bath provided by
a third component, with which they are immiscible. We show that in such a
peculiar effective binary mixture, quantum fluctuations change the equilibrium
of pressures that define the bubble volume and modify as well the criterion for
buoyancy. Once buoyancy sets in, in contrast to the mean-field case, quantum
fluctuations may place the bubble at an intermediate position between the
center and the surface. At the surface, the quantum bubble may transition into
a floating self-bound droplet.Comment: 8 pages, 5 figure
Behavioral and neurochemical studies of inherited manganese-induced dystonia-parkinsonism in Slc39a14-knockout mice
Inherited autosomal recessive mutations of the manganese (Mn) transporter gene SLC39A14 in humans, results in elevated blood and brain Mn concentrations and childhood-onset dystonia-parkinsonism. The pathophysiology of this disease is unknown, but the nigrostriatal dopaminergic system of the basal ganglia has been implicated. Here, we describe pathophysiological studies in Slc39a14-knockout (KO) mice as a preclinical model of dystonia-parkinsonism in SLC39A14 mutation carriers. Blood and brain metal concentrations in Slc39a14-KO mice exhibited a pattern similar to the human disease with highly elevated Mn concentrations. We observed an early-onset backward-walking behavior at postnatal day (PN) 21 which was also noted in PN60 Slc39a14-KO mice as well as dystonia-like movements. Locomotor activity and motor coordination were also impaired in Slc39a14-KO relative to wildtype (WT) mice. From a neurochemical perspective, striatal dopamine (DA) and metabolite concentrations and their ratio in Slc39a14-KO mice did not differ from WT. Striatal tyrosine hydroxylase (TH) immunohistochemistry did not change in Slc39a14-KO mice relative to WT. Unbiased stereological cell quantification of TH-positive and Nissl-stained estimated neuron number, neuron density, and soma volume in the substantia nigra pars compacta (SNc) was the same in Slc39a14-KO mice as in WT. However, we measured a marked inhibition (85–90%) of potassium-stimulated DA release in the striatum of Slc39a14-KO mice relative to WT. Our findings indicate that the dystonia-parkinsonism observed in this genetic animal model of the human disease is associated with a dysfunctional but structurally intact nigrostriatal dopaminergic system. The presynaptic deficit in DA release is unlikely to explain the totality of the behavioral phenotype and points to the involvement of other neuronal systems and brain regions in the pathophysiology of the disease
Continuous rotary membrane emulsification for the production of sustainable Pickering emulsions
A continuous rotary membrane emulsification (cRME) system, allowing the decoupling of droplet generation from continuous phase (CP) flowrate, is presented here for the first time. The decoupling results in higher productivity and greater control compared to traditional crossflow and rotational membrane emulsification processes. A design of experiment (DoE) investigated the influence on droplet formation of CP flow, membrane rotational speed and emulsion composition, using a Pickering emulsion consisting of 1 wt% keratin solution and varying concentrations of oxidised cellulose nanofibrils. Experiments showed that CP flowrate had a negligible effect on droplet diameters in a wide range (between 78 and 241 µm), with uniformity index as low as 0.14 for optimal membrane rotational speeds and different oxidised cellulose nanofibrils (OCNF) concentration. cRME has the potential to overcome low emulsion concentration limitations of continuous membrane emulsification systems, paving the way to significantly increase the productivity and application in personal care, food and drugs industries.</p
Keratin-Chitosan Microcapsules via Membrane Emulsification and Interfacial Complexation
[Image: see text] The continuous fabrication via membrane emulsification of stable microcapsules using renewable, biodegradable biopolymer wall materials keratin and chitosan is reported here for the first time. Microcapsule formation was based on opposite charge interactions between keratin and chitosan, which formed polyelectrolyte complexes when solutions were mixed at pH 5.5. Interfacial complexation was induced by transfer of keratin-stabilized primary emulsion droplets to chitosan solution, where the deposition of chitosan around droplets formed a core–shell structure. Capsule formation was demonstrated both in batch and continuous systems, with the latter showing a productivity up to 4.5 million capsules per minute. Keratin–chitosan microcapsules (in the 30–120 μm range) released less encapsulated nile red than the keratin-only emulsion, whereas microcapsules cross-linked with glutaraldehyde were stable for at least 6 months, and a greater amount of cross-linker was associated with enhanced dye release under the application of force due to increased shell brittleness. In light of recent bans involving microplastics in cosmetics, applications may be found in skin-pH formulas for the protection of oils or oil-soluble compounds, with a possible mechanical rupture release mechanism (e.g., rubbing on skin)
Two new approaches to improve the analysis of BALB/c 3T3 cell transformation assay data
Validation activities of the BALB/c 3T3 cell transformation assay (CTA) – a test method used for the assessment of the carcinogenic potential of compounds – have revealed the need for statistical analysis tailored to specific features of BALB/c 3T3 CTA data. Whereas a standard statistical approach for the Syrian hamster embryo (SHE) CTA was considered sufficient, an international expert group was gathered by the European Centre for the Validation of Alternative Methods (ECVAM) to review commonly applied statistical approaches for BALB/c 3T3 CTA. As it was concluded that none of the commonly applied approaches is entirely appropriate, two novel statistical approaches were found to be recommended for the evaluation of BALB/c 3T3 CTA data accounting for possible non-monotone concentration–response relationship and variance heterogeneity: a negative binomial generalised linear model with William's-type downturn-protected trend tests and a normalisation of the data by a specific transformation allowing for application of a general linear model that estimates effects assuming a normal distribution with William's-type protected tests. Both approaches are described in this article and their performance and the quality of the results they generate is demonstrated using exemplary data. Our work confirmed that both approaches are suitable for the statistical analysis of BALB/c 3T3 CTA data and that each of them is superior to commonly used methods. Furthermore, a procedure dichotomising data into negatives and positives is proposed which allows re-testing in cases where inconclusive data are encountered. The scripts of the statistical evaluation programs written in R – a freely available statistical software – are appended including exemplary outputs
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