This case-control study was designed to investigate the contributing factors for chronic masticatory myofascial pain (MFP). Eighty-three patients with MFP, selected from dental clinics of Jewish General and Montreal Hospitals, Montreal, Canada, 100 concurrent controls only at first clinic, participated in this study. The association MFP evaluated bruxism, head-neck trauma, psychological (symptom check list 90 revised questionnaire, SCL-90R) sociodemographic characteristics by using...

We report new experimental results on granular compaction under consecutive vertical taps. The evolution of the mean volume fraction and potential energy a packing presents slow densification until final steady state, is reminiscent usual relaxation in glasses via stretched exponential law. intensity taps seems to rule characteristic time according an Arrhenius's type relation. Finally, analysis profile reveals almost homogeneous packing.

Several acquisitions of x-ray microtomography have been performed on a beads packing while it compacts under vertical vibrations. An image analysis allows to study the evolution structure during its progressive densification. In particular, volume distribution pores reveals large tail, compatible an exponential law, which slowly reduces as system gets more compact. This is quite consistent, for pores, with free theory. These results are also in very good agreement those obtained by previous...

Contact erosion is potentially initiated at the interface between two soil layers by a groundwater flow within coarser material. Once eroded flow, particles from finer are transported through pores of layer. Fluvial dikes often exposed to this phenomenon. Small-scale experiments combining refractive index matching medium, planar laser-induced fluorescence, and particle image velocimetry were carried out measure characteristics in vicinity an model granular medium fine graded sandy...

We present here experimental results on the progressive development of a fluidized zone in bed grains, immersed liquid, under effect localized upward flow injected through small orifice at bottom bed. Visualization inside model granular medium consisting glass beads is made possible by combined use two optical techniques: refractive index matching between liquid and planar laser-induced fluorescence. Gradually increasing injection rate, three regimes are successively observed: static bed,...

A simple numerical model is used to simulate the effect of vertical taps on a packing monodisperse hard spheres. Our results are in good agreement with an experimental work done Chicago and other previous models, especially concerning dynamics compaction, influence excitation strength compaction efficiency, some aging effects. The principal asset that it allows local analysis packings. Vertical transverse density profiles used, as well size volume distributions pores. An interesting result...

A granular medium submitted to vertical tapping reveals simultaneously compaction and convection. The two phenomena are directly coupled their dynamics can be quantified by a characteristic time an estimation of the convective downhill speed along wall. remarkable change behavior is observed around liftoff acceleration threshold whole packing, with drastic slowing down both below this threshold. Above it, collective shock wave densifies packing at each tap, whereas, cumulative localized...

This article deals with the relevance and practical feasibility of micromechanical simulations for their application to general geomechanical problems involving fluid-saturated granular assemblies, whether frictional or cohesive. A set conceptual numerical tools is here presented, advocating a parallel computation using graphical processing units (GPUs) treat large numbers degrees freedom conventional desktop computers. The fluid phase simulated particle-resolved approach in frame Lattice...

We report experimental results on the evolution of a laminar liquid jet injected with negatively buoyant condition in miscible surrounding liquid. Since molecular diffusion is negligible, only significant effect absence any surface tension. After an initial intrusion phase, reaches steady-state characterized by constant penetration depth. A simple theoretical model derived which successfully predicts transient phase as well subsequent steady state terms stationary depth and jet’s profile....

We present here a numerical study dedicated to the fluidization of submerged granular medium induced by localized fluid injection. To this end, two-dimensional (2D) model is used, coupling lattice Boltzmann method (LBM) with discrete element (DEM) for relevant description fluid-grains interaction. An extensive investigation has been carried out analyze respective influences different parameters our configuration, both geometrical (bed height, grain diameter, injection width) and physical...

The surface erosion of soil samples caused by an impinging jet can be analyzed using the test (JET), a standard experimental to characterize resistance soils. This paper specifically addresses flow characteristics laminar over irregular granular beds discuss pertinence and relevance commonly used empirical estimations based on self-similar model free jet. JET is here investigated at microscale with coupled fluid-particle numerical featuring lattice Boltzmann method (LBM) for fluid phase...

The goal of this paper is to analyze the stochastic dynamics childhood infectious disease time series. We present an univariate series analysis pertussis, mumps, measles and rubella based on Box-Jenkins or AutoRegressive Integrated Moving Average (ARIMA) modeling. method, which enables dependency structure embedded in data be modeled, has potential research applications studies dynamics. Canadian chronological rubella, before after mass vaccination, are analyzed characterize statistical...