Artificial Neural Network Modeling of Glass Transition Temperatures for Some Homopolymers with Saturated Carbon Chain Backbone.

The glass transition temperature (Tg) is an important decision parameter when synthesizing polymeric compounds or when selecting their applicability domain. In this work, the glass transition temperature of more than 100 homopolymers with saturated backbones was predicted using a neuro-evolutive technique combining Artificial Neural Networks with a modified Bacterial Foraging Optimization Algorithm. In most cases, the selected polymers have a vinyl-type backbone substituted with various groups.

Novel organic semiconductors based on 2-amino-anthracene: Synthesis, charge transport and photo-conductive properties.

Anthracene is considered to be a popular choice as a building block for organic semiconductors. The present work is dedicated to the synthesis and characterization of a novel semiconductor (10-OPIA) possessing mesogenic properties, which allows better control over charge transport in the bulk of a material. A novel anthracene-based molecule is characterized for its potential applications: frontier molecular energy levels are studied by optical spectroscopy and cyclic voltammetry and compared to values obtained via ab initio calculations.

Folding time dependence of the motions of a molecular motor in an amorphous medium.

We investigate the dependence of the displacements of a molecular motor embedded inside a glassy material on its folding characteristic time τ_{f}. We observe two different time regimes. For slow foldings (regime I) the diffusion evolves very slowly with τ_{f}, while for rapid foldings (regime II) the diffusion increases strongly with τ_{f}(D≈τ_{f}^{-2}), suggesting two different physical mechanisms.

Motion of Adsorbed Nano-Particles on Azobenzene Containing Polymer Films.

We demonstrate in situ recorded motion of nano-objects adsorbed on a photosensitive polymer film. The motion is induced by a mass transport of the underlying photoresponsive polymer material occurring during irradiation with interference pattern. The polymer film contains azobenzene molecules that undergo reversible photoisomerization reaction from - to -conformation.

How does the motion of the surrounding molecules depend on the shape of a folding molecular motor?

Azobenzene based molecules have the property of isomerizing when illuminated. In relation with that photoisomerization property, azobenzene containing materials are the subject of unexplained massive mass transport. In this work we use an idealised rectangular chromophore model to study the dependence of the isomerization induced transport on the chromophore's dimensions.

A comparative study of photoinduced deformation in azobenzene containing polymer films.

In this paper two groups supporting different views on the mechanism of light induced polymer deformation argue about the respective underlying theoretical conceptions, in order to bring this interesting debate to the attention of the scientific community. The group of Prof. Nicolae Hurduc supports the model claiming that the cyclic isomerization of azobenzenes may cause an athermal transition of the glassy azobenzene containing polymer into a fluid state, the so-called photo-fluidization concept.

Fluorescent polymeric aggregates for selective response to sarin surrogates.

By combining the sensitivity of fluorescent units with the response of "smart" polymers to environmental changes, we propose a new approach for chemical detection applications. The system proved to be sensitive to 12 ppb of diethyl chlorophosphate (DCP), a Sarin surrogate, and to discriminate between the interfering molecules.

Direct observation of athermal photofluidisation in azo-polymer films.

The surface relief gratings (SRGs) can be generated when azo-polymer films are exposed to laser beam interference as a result of mass migration. Despite considerable research effort over the past two decades this complex phenomenon remains incompletely understood. Here we show, for the first time, the athermal photofluidisation of azo-polysiloxane films exposed to 488 nm light, directly monitored by optical microscopy.

An atomic force microscopy statistical analysis of laser-induced azo-polyimide periodic tridimensional nanogrooves.

The surface morphology of azo-polyimide films was investigated after 355 nm Nd: YAG laser irradiation with two different incident fluencies. Atomic force microscopy (AFM) was employed to correlate the laser-induced tridimensional nanogrooved surface relief with the incident fluence and the number of irradiation pulses. The height images revealed that the grooves depth increased even tens of times by increasing the incident fluence, using the same numbers of irradiation pulses.

Azo-polysiloxanes as new supports for cell cultures.

The paper introduces a new class of materials with azo-polysiloxanic structure bearing the property to generate nano-structured surfaces by laser irradiation. The ability to modulate the optical response of the film, through a modification of the polymer chemical structure, has been investigated. The azo-materials were tested for their ability to support cell adhesion and growth, with very promising results.

Polydiphenylsilanes bearing photosensitive azocrown groups.

This work presents the synthesis and particularities of the reversible trans-cis UV light induced photoisomerization process of a polydiphenylsilane bearing (propyl-oxyphenylazo)dibenzo-18-crown-6 side groups.

Diagnosis difficulties in multiple myeloma.

Some difficulties in the diagnosis of multiple myeloma are presented. The atypical onset (pseudorheumatismal, anaemic, renal or neurological one) as well as the presence of a biological syndrome during some other diseases which may generate the confusion with the multiple myeloma are discussed with reference to the personal casuistry (30 cases of multiple myeloma in a lapse of 12 years). Some peculiar cases of the two categories of difficulties are presented in detail.

[The experience of the 3rd Medical Clinic with lymph node pathology].

In the last 8 years, 511 patients (267 men and 244 women) were investigated. It was found that 44 cases (8.6%) were false adenopathies (various types of tumoral masses) but placed in the nodes areas (localized, generalized or deep).