Shock conditions and shock wave structures in a steady flow in a dissipative fluid

More precisely, calling xi the reciprocal of the Reynolds number based on the shock wave curvature radius, the xi terms of the first order are systematically taken into account. The most important result is a system of formulas giving a correction of order xi for the various RANKINE-HUGONIOT conditions. The suggested formulas may for instance have to be used instead of the conventional ones to evaluate the loss of the total pressure across the detached shock wave which is found at the nose of a very small probe in supersonic flow

Extreme Value Theory for Piecewise Contracting Maps with Randomly Applied Stochastic Perturbations

We consider globally invertible and piecewise contracting maps in higher dimensions and we perturb them with a particular kind of noise introduced by Lasota and Mackey. We got random transformations which are given by a stationary process: in this framework we develop an extreme value theory for a few classes of observables and we show how to get the (usual) limiting distributions together with an extremal index depending on the strength of the noise.Comment: 16 pages. arXiv admin note: text overlap with arXiv:1407.041

A one dimensional model for the prediction of extraction yields in a two phases modified twin-screw extruder

Solid/liquid extraction is performed on raw plant substrate with a modified twin-screw extruder (TSE) used as a thermo-mecanochemical reactor. Visual observations and experimental residence time distributions (RTD) are used to develop a solid transport model based on classical chemical engineering method. Modeled and experimental residence times are compared. The transport model is then coupled with a reactive extraction model in order to predict extraction yields

Dipyridamole plus aspirin versus aspirin alone in the secondary prevention after TIA or stroke: a meta-analysis by risk

Objectives: Our aim was to study the effect of combination therapy with aspirin and dipyridamole (A+D) over aspirin alone (ASA) in secondary prevention after transient ischemic attack or minor stroke of presumed arterial origin and to perform subgroup analyses to identify patients that might benefit most from secondary prevention with A+D. Data sources: The previously published meta-analysis of individual patient data was updated with data from ESPRIT (N=2,739); trials without data on the comparison of A+D versus ASA were excluded. Review methods: A meta-analysis was performed using Cox regression, including several subgroup analyses and following baseline risk stratification. Results: A total of 7,612 patients (5 trials) were included in the analyses, 3,800 allocated to A+D and 3,812 to ASA alone. The trial-adjusted hazard ratio for the composite event of vascular death, non-fatal myocardial infarction and non-fatal stroke was 0.82 (95% confidence interval 0.72-0.92). Hazard ratios did not differ in subgroup analyses based on age, sex, qualifying event, hypertension, diabetes, previous stroke, ischemic heart disease, aspirin dose, type of vessel disease and dipyridamole formulation, nor across baseline risk strata as assessed with two different risk scores. A+D were also more effective than ASA alone in preventing recurrent stroke, HR 0.78 (95% CI 0.68 – 0.90). Conclusion: The combination of aspirin and dipyridamole is more effective than aspirin alone in patients with TIA or ischemic stroke of presumed arterial origin in the secondary prevention of stroke and other vascular events. This superiority was found in all subgroups and was independent of baseline risk. ---------------------------7dc3521430776 Content-Disposition: form-data; name="c14_creators_1_name_family" Halke

Two phase residence time distribution in a modified twin screw extruder

Biomass fractionation is performed with a modified Clextral twin-screw extruder used as a thermo-mechano-chemical reactor. This new process is firstly analyzed. Visual observations, residence time distributions, and global mass balances are used to obtain information about the process phenomena and their coupling. Residence time distributions (RTD) classical models are adopted to represent the experimental plots. The influence of continuous and discrete process parameters upon the RTD of the solid and liquid phases is analyzed

Review: Removal of oversize & recovery of particles from suspensions in the nano size range

The review will try to answer to two main goals: the product classification and the productremoval in the nano-size range and specifically applied to wet suspensions. The productclassification means the removal of the coarse fraction from a size distribution, targetingspecific size regimes (e.g. those > 0.5 μm and those > 100nm). The product recovery is theremoval of all particles from a suspension, down to several nanometers. In that case however,the separation may be done differently if the product of interest is the solid (the separation isfocused on the recovery of particles in the nano-size range) or the liquid phase (the separationis focused on the liquid phase purification).Usually, one considers that nanoparticles are particles having their three dimensions lowerthan 100 nm. The size range covered by this review varies from a few nanometers to severalmicrons or even more. One raison is that nanoseparation processes are often not specifictechnologies but current technologies that have been extended towards the submicronic range

Exhumation of the Sierra de Cameros (Iberian Range, Spain): constraints from low-temperature thermochronology

We present new fission-track and (U–Th)/He data from apatite and zircon in order to reconstruct the exhumation of the Sierra de Cameros, in the northwestern part of Iberian Range, Spain. Zircon fission-track ages from samples from the depocentre of the basin were reset during the metamorphic peak at approximately 100 Ma. Detrital apatites from the uppermost sediments retain fission-track age information that is older than the sediment deposition age, indicating that these rocks have not exceeded 110 8C. Apatites from deeper in the stratigraphic sequence of the central part of the basin have fission-track ages of around 40 Ma, significantly younger than the stratigraphic age, recording the time of cooling after peak metamorphic conditions. Apatite (U–Th)/He ages in samples from these sediments are 31–40 Ma and record the last period of cooling during Alpine compression. The modelled thermal history derived from the uppermost sediments indicates that the thermal pulse associated with peak metamorphism was rapid, and that the region has cooled continuously to the present. The estimated palaeogeothermal gradient is around 86 8C km21 and supports a tectonic model with a thick sedimentary fill (c. 8 km) and explains the origin of the low-grade metamorphism observed in the oldest sediments

Effets de scenarios de changements climatiques sur la cacaoculture en Cote d’Ivoire

L’influence des scenarios de changements climatiques a été analysée pour les régions Centre et Sud de production cacaoyère en Côte d’Ivoire. A partir des modèles RCP 4.5 et 8.5 de concentration des Gaz à Effets de Serre (GES), les paramètres température et pluviométrie ont été projetés sur les horizons 2021-2050 et 2041-2070 en comparaison à la période de référence 1980-2010. Les résultats ont montré qu’en dehors du nombre élevé de jours chauds qui pourrait provoquer la disparition de la cacaoculture dans les zones marginales de la région Centre, les indices climatiques se situent dans des conditions normales de production du cacaoyer dans les deux régions. Les risques liés aux maladies et ravageurs pourraient être similaires ou potentiellement réduits. En région Sud, les variations climatiques n’auraient aucun impact sur la cacaoculture. Comme stratégies de résilience, les programmes de sélection variétale devront mettre à la disposition des producteurs un matériel végétal tolérant à la sécheresse et aux maladies accompagnée de formations sur les bonnes pratiques agricoles dont l’agroforesterie. Toutefois, l’accès des producteurs à l’information météorologique devra être renforcé.  English title: Climate change effects in cocoa cultivation Abstract The influence of climate change scenarios was analyzed for the Center and South regions of cocoa farming in Côte d’Ivoire. From greenhouse gas (GHG) concentration models RCP 4.5 and 8.5, the parameters of temperature and rainfall were projected over the time in years 2021-2050 and 2041- 2070 compared to year 1980-2010 as reference period. The results showed that apart from the high number of hot days which could cause the disappearance of cocoa farming in marginal areas of the Center region, the climatic indices are normal within cocoa production conditions in both regions. Risks on cocoa pests and disease could be similar or potentially reduced. In the South region, climatic variations would have no impact on cocoa farming. As resilience adaptation strategies, tolerant germplasm to drought and pest and disease should be provided to farmers by cocoa research program with training package on good agricultural practices (GAP) including agroforestry. Therefore, theaccess to meteorological information has to be strengthened for smallholders cocoa farmers. Key words: Climate change scenarios, impact, cocoa farming, Côte d’Ivoire

Transverse intrafascicular multichannel electrode (TIME) system for treatment of phantom limb pain in amputees

International audienceAIM: Phantom limb pain (PLP) develops in the lost limb in 50-80% of amputees. Today, it is not completely understood why the pain occurs, and no effective treatments are available. The favorable effect of electrical stimulation on PLP has been demonstrated. Our aim is to develop a novel system for manipulation of sensations by application of multi-channel microstimulation to the nerve stump of an amputee and explore this method as a treatment for clinched fist PLP (see figure). RESULTS: 1) Electrode design. Non-corrugated TIME electrodes with different dimensions and 8-12 active sites have been manufactued and tested in vivo and in vitro testing in the rat and pig. Methods for corrugated prototypes were developed and the first prototypes were realized. 2) Electrode selectivity modeling. A peripheral nerve model is under development to evaluate the electrode's selective stimulation properties and to optimize electrode design. Simulated currents and neural activity generated were qualitatively assessed using experimental data obtained from rat nerves. 3) Implant modeling. To optimize the implantation procedure, a theoretical peripheral nervous tissue model and a 3D FEM was implemented. Both models closely reproduce the experimental peripheral nervous tissue behaviour and simulate the insertion forces transmitted to the electrode during implantation. 4) Multi-channel stimulators and connectors. A 12-pole prototype, bench-top stimulator has been implemented and successfully tested in animal experiments. A high-count, implantable connector between stimulator and electrode has been designed. 5) Biocompatibility. Electrode materials were evaluated and did not induce immune rejection and significant inflammatory reaction after in vivo implantation in the rat. Electrode implantation will require an understanding of the fascicular characteristics of the target nerve. Morphological characteristics of the rat, pig and human nerves are currently evaluated and compared. 6) Animal testing. First TIME electrodes test were carried out in the acute rat and acute pig. Results indicated selective stimulation of different fascicles with graded recruitment. 7) Clinical evaluation: To quantify the location of artificially evoked sensations and evaluate the strength of artificially evoked sensations a psychophysical testing platform is under development. Main inclusion criteria for patient recruitment have been identified and protocols have been defined. CONCLUSION: The feasibility of the corrugated version of the TIME electrode has yet to be explored. Further work designing, optimizing and testing the TIME electrode and all technological developments will be carried out including theoretical stimulations and animal experimental work before the optimal electrode for human implant will be chosen