Optical microtube cavities monolithically integrated on photonic chips for optofluidic sensing.

Microtubular optical resonators are monolithically integrated on photonic chips to demonstrate optofluidic functionality. Due to the compact subwavelength-thin tube wall and a well-defined nanogap between polymer photonic waveguides and the microtube, excellent optical coupling with extinction ratios up to 32 dB are observed in the telecommunication relevant wavelength range. For the first time, optofluidic applications of fully on-chip integrated microtubular systems are investigated both by filling the core of the microtube and by the microtube being covered by a liquid droplet. Total shifts over the full free spectral range are observed in response to the presence of the liquid medium in the vicinity of the microtube resonators. This work provides a vertical coupling scheme for optofluidic applications in monolithically integrated so-called "lab-in-a-tube" systems.

Synthesis of multifunctional plasmonic nanopillar array using soft thermal nanoimprint lithography for highly sensitive refractive index sensing.

A low-cost plasmonic nanopillar array was synthesized using soft thermal nanoimprint lithography, and its sensitivity was determined through far-field spectroscopic measurements. Its transmission spectrum was highly dependent on the refractive index of the surrounding medium, with its sensitivity being 375 nm per refractive index unit according to the spectral shift. Moreover, a simple sensor whose reflected color changed with a change in the plasma frequency on varying the surrounding medium was fabricated.

In situ experiments to reveal the role of surface feature sidewalls in the Cassie-Wenzel transition.

Waterproof and self-cleaning surfaces continue to attract much attention as they can be instrumental in various different technologies. Such surfaces are typically rough, allowing liquids to contact only the outermost tops of their asperities, with air being entrapped underneath. The formed solid-liquid-air interface is metastable and, hence, can be forced into a completely wetted solid surface. A detailed understanding of the wetting barrier and the dynamics of this transition is critically important for the practical use of the related surfaces. Toward this aim, wetting transitions were studied in situ at a set of patterned perfluoropolyether dimethacrylate (PFPEdma) polymer surfaces exhibiting surface features with different types of sidewall profiles. PFPEdma is intrinsically hydrophobic and exhibits a refractive index very similar to water. Upon immersion of the patterned surfaces into water, incident light was differently scattered at the solid-liquid-air and solid-liquid interface, which allows for distinguishing between both wetting states by dark-field microscopy. The wetting transition observed with this methodology was found to be determined by the sidewall profiles of the patterned structures. Partial recovery of the wetting was demonstrated to be induced by abrupt and continuous pressure reductions. A theoretical model based on Laplace's law was developed and applied, allowing for the analytical calculation of the transition barrier and the potential to revert the wetting upon pressure reduction.

Biologically inspired omniphobic surfaces by reverse imprint lithography.

Springtail skin morphology is translated into robust omniphobic polymer membranes by reverse imprint lithography. The combination of overhanging cross-sections and their arrangement in a self-supporting comblike pattern are crucial for mechanically stable coatings that can be even applied to curved surfaces.

Preliminary report on the living non-marine Ostracoda (Crustacea) from Tunisia with the description of a new Psychrodromus species.

Since 1928, Henri Gauthier has been the only zoologist to describe the extant non-marine ostracod fauna of Tunisia. In 2010, new samples of living non-marine ostracods were collected from central and southern Tunisia. A complete list of the 41 non-marine ostracods of Tunisia is presented, including the species of Gauthier's work, published Holocene records, and new results from our field study. Historical faunal variations (El Melah Lagoon, Lac de Tunis, Sebkhas El- Guettiate and Dreiaa, and Lac Ichkeul) are briefly discussed and related to recent environmental changes. In 2006, El Melah Lagoon contained a freshwater, brackish, and a marine ostracod assemblage. In the future, this lagoon will probably dry up and become a sebkha. Lac de Tunis has developed from a marine bay over a lagoon connected to the Mediterranean Sea to a brackish/freshwater environment. Sebkhas El-Guettiate and Dreîaa have developed from marine bays to dry salt flats. Lac Ichkeul is eutrophied and has become brackish since the time of Gauthier. We also describe a new species, Psychrodromus tunisicus n. sp., and present a determination key for the genus. The finding of a species of the genus Psychrodromus is the first report of this genus in North Africa.

Reabsorçäo radicular pós-tratamento ortodöntico pela técnica de Tweed / Radicular resorption of upper incisors after orthodontic treatment by tweed technique

O objetivo deste trabalho é analisar radiograficamente as reabsorçöes radiculares apicais em uma amostragem de pacientes submetidos a tratamento ortodôntico pela técnica de Tweed. Foram consideradas as seguintes variáveis: duraçäo do tratamento ortodôntico, sexo, idade e tipo de movimento realizado