The nasal mucosa provides a potentially good route for local and systemic drug delivery. However, the protective feature of the nasal cavity make intranasal delivery challenging. The application of mucoadhesive polymers in nasal drug delivery systems enhances the retention of the dosage form in the nasal cavity. Several groups have investigated using low acyl gellan as a drug delivery vehicle b...

The role of a finite exposure time sigma on measuring rheological properties using microrheology techniques is theoretically investigated. We concentrate on studying fluid models displaying a plateau in the mean-squared displacement (MSD) of the embedded probe particle. A model is developed to compare the resulting experimentally measured MSD of the particle to its expected value in the fluid m...

We describe a new approach to understanding the progressive transition from linear to nonlinear rheological response in complex fluids and soft solids. Large amplitude oscillatory shear (LAOS) tests are carried out over a wide range of frequencies and strain amplitudes. The resulting material response to an oscillatory input can be represented in terms of Lissajous figures and can also be decom...

The nonlinear rheological response of soft glassy materials is addressed experimentally by focusing on concentrated emulsions where interdroplet attraction is tuned through varying the surfactant content. Velocity profiles are recorded using ultrasonic velocimetry simultaneously to global rheological data in the Couette geometry. Our data show that nonadhesive and adhesive emulsions have radica...

A new paradigm of rheological characterization, oscillatory simple shear with infinite forcing amplitudes, is introduced by Khair (J. Fluid Mech., vol. 791, 2016, R5). This pushes the technique of large-amplitude oscillatory shear (LAOS) to have two extremely large amplitudes (both strain-rate and strain), which we might call XXLAOS. Model-specific analytical predictions are derived for a suspe...

The validity of fluctuation dissipation relations in an aging system is studied in a colloidal glass during the transition from a fluid-like to a solid-like state. The evolution of the rheological and electrical properties is analyzed in the range 1Hz − 40Hz. It is found that at the beginning of the transition the fluctuation dissipation relation is strongly violated in electrical measurements....

This paper is concerned with the rheological modelling of untreated Carbon Nanotubes (CNTs) suspended within an epoxy resin and its application in nanocomposites forming processes. The untreated CNT suspensions exhibited significant steady shear-thinning and contained optically resolvable aggregate structures. A simple orientation model, based on a Fokker-Planck advection–diffusion description,...

The exact knowledge of the blood vessel geometry plays an important role, not only in clinical applications (stroke diagnosis, detection of stenosis), but also for detailed analysis of functional data, such as fMRI or optical imaging data. Here we focus on validating not only the geometry of the extracted vascular pattern, but also its function, namely the fluid dynamics. For validating angiogr...

The validity of fluctuation dissipation relations in an aging system is studied in a colloidal glass during the transition from a fluid-like to a solid-like state. The evolution of the rheological and electrical properties is analyzed in the range 1Hz − 40Hz. It is found that at the beginning of the transition the fluctuation dissipation relation is strongly violated in electrical measurements....

The phase diagram of alpha -cyclodextrin/water/4-methylpyridine solutions, a system undergoing inverse melting, has been studied by differential scanning calorimetry, rheological methods, and x-ray diffraction. Two different fluid phases separated by a solid region have been observed in the high alpha -cyclodextrin concentration range (c > or =150 mg/ml) . Decreasing c , the temperature interva...