Publications by authors named "J P Boitte"

Objective: As every skin type worldwide is concerned by photoprotection, with consumers preferring cosmetic elegant and efficient sunscreen products, we aim at developing the most performant and desirable sun care products.

Methods: We selected an interesting polymer, abbreviated AAHCP and designed scanning electron cryomicroscopy (cryoSEM), small angle and wide angle X-ray scattering and confocal laser scanning microscopy studies to understand its behaviour in solution and in simplex sun care formulations. This allowed us to develop innovative sunscreen formulation technology that was demonstrated by in vitro and in vivo photoprotection methods.

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Starch suspensions are often used as model systems to demonstrate extreme shear-thickening effects. We study the aging of cornstarch particles in aqueous suspensions at room temperature by granulometry and rheological measurements. When starch is diluted in glycerol, no long-term changes are observed.

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We study the spreading of a Newtonian fluid by a deformable blade, a common industrial problem, characteristic of elastohydrodynamic situations. Here, we consider the case of a finite reservoir of liquid, emptying as the liquid is spread. We evidence the role of a central variable: the wetting length l_{w}, which sets a boundary between the wet and dry parts of the blade.

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A new rheo-optical shearing device was designed to investigate the structural evolution of complex material under shear flow. Seeking to keep the area under study constantly within the field of vision, it was conceived to produce shear flow by relying on the uniaxial translation of two parallel plates. The device features three modes of translation motion: step strain (0.

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The purpose of this prospective observational study was to evaluate the extent of visual impairment in a socially and professionally active population attending the Tropical Ophthalmology Institute of Africa (IOTA). Thanks to high recruitment rate at the IOTA, which is the third reference eye centre, a total of 828 patients ranging from 18 and 50 years of age and consulting for the first time were included between February 1 and May 4, 2003. Each patient underwent a thorough ocular examination.

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