Viscosity and yield stress reduction in non-colloidal concentrated suspensions by surface modification with polymers and surfactants and/or nanoparticle addition.

A custom-designed apparatus termed the yield stress adaptor (YSA) has been used to evaluate the effect of polymer-surfactant coatings, and the addition of nanoparticles of different size, shape and surface chemistry, on the rheological properties of large hydrophilic particulates, sand, with the aim of reducing interparticle friction forces. Experimental results show that the flow properties of sand slurries at high volume fractions of sand (>50%) can be significantly enhanced by adding nanoparticles, and by surface modification with polymer/surfactant mixtures. A lesser effect is observed for polymer-only and surfactant-only coated samples.

Cilia ultrastructure in children with Down syndrome.

Chronic sinusitis, otitis media with effusion, and upper respiratory tract infections are commonly found in patients with Down syndrome. These diseases are generally felt to be secondary to depressed immune function and altered craniofacial dimensions. Recently, a cilia ultrastructure abnormality was found in a child with Down syndrome.

Combination of ceftriaxone and acyclovir - an underestimated nephrotoxic potential?

Management of meningo-encephalitis often involves the need for antibiotic and antiviral treatment. We report a retrospective analysis over a 6-month period of 17 patients (age range 1-14 years) who were treated with combination therapy of ceftriaxone and acyclovir. Mean acyclovir and ceftriaxone doses were 1,222+/-304 and 2,315+/-509 mg/m(2) per day, respectively.

Optimal biopsy techniques in the diagnosis of primary ciliary dyskinesia.

Objective: Adequate biopsy specimens that clearly demonstrate cilia, and therefore enable the determination of the presence or absence of primary cilia dyskinesia, may be difficult to obtain. This study is an attempt to identify the optimal sampling technique to best examine respiratory tract cilia.

Design: A prospective comparison of the four sampling techniques was carried out: nasal brushing, nasal biopsy, bronchial brushing, and tracheal biopsy.