Modeling of time-resolved laser-induced incandescence transients for particle sizing in high-pressure spray combustion environments: a comparative study

In this study experimental single-pulse, time-resolved laser-induced incandescence (TIRE-LII) signal intensity profiles acquired during transient Diesel combustion events at high pressure were processed. Experiments were performed between 0.6 and 7MPa using a high-temperature high-pressure constant volume cell and a heavy-duty Diesel engine, respectively. Three currently available LII sub-model functions were investigated in their performance for extracting ensemble mean soot particle diameters using a least-squares fitting routine, and a "quick-fit” interpolation approach, respectively. In the calculations a particle size distribution as well as the temporal and spatial intensity profile of the heating laser was taken into account. For the poorly characterized sample environments of this work, some deficiencies in these state-of-the-art data evaluation procedures were revealed. Depending on the implemented model function, significant differences in the extracted particle size parameters are apparent. We also observe that the obtained "best-fit” size parameters in the fitting procedure are biased by the choice of their respective "first-guess” initial values. This behavior may be caused by the smooth temporal profile of the LII cooling curve, giving rise to shallow local minima on the multi-parameter least squares residuals, surface sampled during the regression analysis procedure. Knowledge of the gas phase temperature of the probed medium is considered important for obtaining unbiased size parameter information from TIRE-LII measurement

Visualization of perfusion changes with laser speckle contrast imaging using the method of motion history image

Laser speckle contrast imaging (LSCI) is a real-time imaging modality reflecting microvascular perfusion. We report on the application of the motion history image (MHI) method on LSCI data obtained from the two hemispheres of a mouse. Through the generation of a single image, MHI stresses the microvascular perfusion changes. Our experimental results performed during a pinprick-triggered spreading depolarization demonstrate the effectiveness of MHI: MHI allows the visualization of perfusion changes without loss of resolution and definition. Moreover, MHI provides close results to the ones given by the generalized differences (GD) algorithm. However, MHI has the advantage of giving information on the temporal evolution of the perfusion variations, which GD does not

Optical diagnostics of diesel spray injections and combustion in a high-pressure high-temperature cell

We report on spatially and temporally resolved optical diagnostic measurements of propagation and combustion of diesel sprays introduced through a single-hole fuel injector into a constant volume, high-temperature, high-pressure cell. From shadowgraphy images in non-reacting environments of pure nitrogen, penetration lengths and dispersion angles were determined for non-vaporizing and vaporizing conditions, and found to be in reasonable agreement with standard models for liquid jet propagation and break-up. Quasi-simultaneous two-dimensional images were obtained of laser elastic light scattering, shadowgraphs and spectrally integrated flame emission in a reacting environment (cell temperature 850 K). In addition laser-induced incandescence was employed for the identification of soot-loaded regions. The simultaneously recorded spray images exhibit remarkable structural similarity and provide complementary information about the spray propagation and combustion process. The measurements also reveal the fuel vapor cloud extending well beyond the liquid core and close to the nozzle tip. Ignition takes place close to the tip of the spray within the mixing layer of fuel vapor and surrounding air. Soot is formed in the vapor core region at the tip of the liquid fuel jet. Our results support recently developed phenomenological model on diesel spray combustio

A DARPin-based molecular toolset to probe gephyrin and inhibitory synapse biology

Neuroscience currently requires the use of antibodies to study synaptic proteins, where antibody binding is used as a correlate to define the presence, plasticity, and regulation of synapses. Gephyrin is an inhibitory synaptic scaffolding protein used to mark GABAergic and glycinergic postsynaptic sites. Despite the importance of gephyrin in modulating inhibitory transmission, its study is currently limited by the tractability of available reagents. Designed Ankyrin Repeat Proteins (DARPins) are a class of synthetic protein binder derived from diverse libraries by in vitro selection, and tested by high-throughput screening to produce specific binders. In order to generate a functionally diverse toolset for studying inhibitory synapses, we screened a DARPin library against gephyrin mutants representing both phosphorylated and dephosphorylated states. We validated the robust use of anti-gephyrin DARPin clones for morphological identification of gephyrin clusters in rat neuron culture and mouse brain tissue, discovering previously overlooked clusters. This DARPin-based toolset includes clones with heterogenous gephyrin binding modes that allowed for identification of the most extensive gephyrin interactome to date, and defined novel classes of putative interactors, creating a framework for understanding gephyrin's non-synaptic functions. This study demonstrates anti-gephyrin DARPins as a versatile platform for studying inhibitory synapses in an unprecedented manner

Theorising interprofessional pedagogic evaluation: framework for evaluating the impact of interprofessional CPD on practice change

This paper outlines the development of a conceptual framework to guide the evaluation of the impact of the pedagogy employed in continuing professional development for professionals in education, health and social care. The work is developed as part of the Centre for Excellence in Teaching and Learning: Interprofessional Learning across the Public Sector (CETL: IPPS) at the University of Southampton. The paper briefly outlines the field for pedagogic research and comments on the underpinning theories that have so far been used to guide research into interprofessional learning (IPL). It maps out the development of interprofessional CPD in its specific context as part of the CETL: IPPS with its links to a local authority undergoing service reorganisation and the role of the continuing professional development (CPD) in effecting change. It then brings together a theoretical framework with the potential toexplore, explain and evaluate the essential features of the model of pedagogy used in interprofessional CPD, in which professionals from education have for the first time been included alongside those from health and social care. The framework draws upon elements of situated learning theory, Activity Theory and Dreier’s work (2002, 1999) on trajectories of participation, particularly Personal Action Potency. By combining the resulting analytic framework with an adapted version of an established evaluation model, a theoretically-driven, practicable evaluation matrix is developed. The matrix has potential use in evaluating the impact of pedagogic input on practice change. The paper models a process for developing a conceptual framework to steer pedagogic evaluation. Such a process and the resulting matrix may be of use to other researchers who are similarly developing pedagogic evaluation

Bumblebee family lineage survival is enhanced in high quality landscapes

Insect pollinators such as bumblebees (Bombus spp.) are in global decline1,2, a major cause of which is habitat loss due to agricultural intensification3. A range of global and national initiatives aimed at restoring pollinator habitats and populations have been developed4-6. However, the success of these initiatives depends critically upon understanding how landscape change affects key population-level parameters, such as survival between lifecycle stages7, in target species. Such understanding is lacking for bumblebees because of the difficulty of systematically finding and monitoring colonies in the wild. We used a novel combination of habitat manipulation, land-use and habitat surveys, molecular genetics8 and demographic and spatial modelling to examine between-year survival of family lineages in field populations of three bumblebee species. Here we show that the survival of family lineages from the summer worker to the spring queen stage in the following year increases significantly with the proportion of high-value foraging habitat, including spring floral resources, within 250-1000 m of the natal colony. This is the first evidence of a positive impact of habitat quality on survival and persistence between successive colony cycle stages in bumblebee populations. The findings provide strong support for conservation interventions that increase floral resources at a landscape scale and throughout the season having positive effects on wild pollinators in agricultural landscapes

Cerebral Lactate Correlates with Early Onset Pneumonia after Aneurysmal SAH

Pneumonia is a significant medical complication following aneurysmal subarachnoid hemorrhage (aSAH). The aSAH may initiate immune interactions leading to depressed immunofunction, followed by an increased risk of infection. It remains unclear as to whether there is a possible association between cerebral metabolism and infections. Clinical and microdialysis data from aSAH patients prospectively included in the CoOperative Study on Brain Injury Depolarisations protocol Berlin were analyzed. Levels of glucose, lactate, pyruvate, and glutamate were measured hourly using microdialysis in the cerebral extracellular fluid. The occurrence of pneumonia (defined by positive microbiological cultures) and delayed ischemic neurological deficits (DIND) was documented prospectively. Eighteen aSAH patients (52.7 ± 10.7years), classified according to the World Federation of Neurological Surgeons in low (I-III, n = 9) and high (IV-V, n = 9) grades, were studied. Eight patients (45%) experienced DIND, 10 patients (56%) pneumonia (mean onset day 2.6). Lactate was elevated at day 3 in infected patients (n = 9, median = 6.82mmol/L) vs. patient without infections (n = 6, median = 2.90mmol/L, p = 0.036). The optimum cut-off point to predict pneumonia at day 3 was 3.57mmol/L with a sensitivity of 0.77, and a specificity of 0.66 (area under curve was 0.833 with p = 0.034). Lactate at day 7 was higher in DIND patients compared to no-DIND-patients (p = 0.016). Early elevated lactate correlated with occurrence of bacterial pneumonia, while late elevations with DIND after aSAH. Future investigations may elucidate the relationship between cerebral lactate and markers of immunocompetence and more detailed to identify patients with higher susceptibility for infections

Enforcing Privacy in the Presence of Others: Notions, Formalisations and Relations

Protecting privacy against bribery/coercion is a necessary requirement in electronic services, like e-voting, e-auction and e-health. Domain-specific privacy properties have been proposed to capture this. We generalise these properties as enforced privacy: a system enforces a user's privacy even when the user collaborates with the adversary. In addition, we account for the influence of third parties on a user's privacy. Third parties can help to break privacy by collaborating with the adversary, or can help to protect privacy by cooperating with the target user. We propose independency of privacy to capture the negative privacy impact that third parties can have, and coalition privacy to capture their positive privacy impact. We formally define these privacy notions in the applied pi calculus and build a hierarchy showing their relations