“I’m a Red River local”: rock climbing mobilities and community hospitalities

With individuals continually on the move, mobility fosters constellations of places at which individuals collectively moor and perform community. By focusing on one climbing destination – the Red River Gorge – this paper works across scales to highlight the spatial politics of mobilizing hospitality. In so doing, it summarizes the ways hosting/guesting thresholds dissolve with the growth of particular rock climbing associated infrastructures and moves to examine the ways climbers performances of community result in the (semi-)privatization of public space and attempts at localization. Further, the paper highlights the ways mobility is employed to maintain a political voice from afar, as well as to forge “local” identities with The Red as place with distinct subcultural (in)hospitality practices. Hospitality practices affirm power relations, they communicate who is at “home” and who has the power in a particular space to extend hospitality. The decision to extend hospitality is not simply the difference between an ethical encounter and a conditional one; it takes place in the very performance of identity. Thus, integrating a mobilities perspective into hospitality studies further illuminates the spatial politics that are at play in an ethics of hospitality

Wormhole formation in dissolving fractures

We investigate the dissolution of artificial fractures with three-dimensional, pore-scale numerical simulations. The fluid velocity in the fracture space was determined from a lattice-Boltzmann method, and a stochastic solver was used for the transport of dissolved species. Numerical simulations were used to study conditions under which long conduits (wormholes) form in an initially rough but spatially homogeneous fracture. The effects of flow rate, mineral dissolution rate and geometrical properties of the fracture were investigated, and the optimal conditions for wormhole formation determined.Comment: to be published in J. Geophys Re

DETERMINATION OF THE KINETIC PARAMETERS OF OXY-FUEL COMBUSTION OF COAL WITH A HIGH ASH CONTENT

Abstract The aim of this study was to determine the kinetic parameters of the oxy-fuel combustion of char from a Brazilian bituminous coal with a high ash content. The char, with a particle diameter of 715 μm, was prepared in a N2 atmosphere at 1173 K. The oxy-fuel combustion assays were performed using a thermobalance at different temperatures and O2/CO2 gas mixtures of different concentrations. According to the unreacted core model, the process is determined by chemical reaction at low temperatures, with an activation energy of 56.7 kJ.kmol-1, a reaction order of 0.5 at 973 K and a reaction order of 0.7 overall. The use of the continuous reaction model did not provide a good fit for the experimental data because the consumption of the particles during the reaction was not constant, as predicted by the model. According to the Langmuir-Hinshelwood model, the activation energy for the first step was 37.3 kJ.kmol-1

Synthesis of substituted diazino[c]quinolin-5(6H)-ones, diazino[c]isoquinolin-6(5H)-ones, diazino[c]naphthyridin-6(5H)-ones and diazino[c]naphthyridin-5(6H)-ones

International audienceSubstituted diazino[c]quinolin-5(6H)-ones and -isoquinolin-6(5H)-ones, diazino[c]naphthyridin-6(5H)- and -5(6H)-ones were obtained using two synthetic routes: one-pot cross-coupling/cyclization and two-step cross-coupling/KOH-mediated anionic ring closure. The two strategies gave yields in the same order of magnitude and their choice depends on the availability of the starting material

A climate-driven abundance model to assess mosquito control strategies

As mosquitoes are vectors of major pathogens worldwide, the control of mosquito populations is one way to fight vector-borne diseases. The objectives of our study were to develop a tool to predict mosquito abundance over time, identify the main determinants of mosquito population dynamics, and assess mosquito control strategies. We developed a generic, mechanistic, climate-driven model of seasonal mosquito population dynamics that can be run over several years because it takes diapause into account. Both aquatic and adult stages are considered, resulting in 10 model compartments: eggs, larvae, and pupae for juveniles; emergent, nulliparous, and parous for adults, the latter two broken down into host-seeking, resting, and ovipositing adults. We then applied the model to Anopheles species of southern France, some of which (nulliparous adults) overwinter. We defined specific transition functions and parameter values for these species and this geographical area based on a literature review. Our model correctly predicted entomological field data. Control points in the model were related to mortality rates of adults, the sex-ratio at emergence, parameters related to development functions and the number of eggs laid by females. Lastly, we used our model to compare the efficiency of mosquito control strategies targeting larvae. We found that a larvicide spraying at regular time intervals acted as a preventive measure against mosquito emergence, and that such a strategy was more efficient than spraying only when the abundance of host-seeking females reached a given threshold. The proposed model can be applied easily to other mosquito species and geographic areas by adapting transition functions and parameter values