Degradation Analysis of Exciplex-Based Organic Light-Emitting Devices Using Carbazole-Based Materials.

A spectral shift and new emission bands in the green and red regions have been observed in deep blue exciplex-based organic light-emitting diodes (OLEDs) using carbazole-based materials, namely, tris(4-carbazoyl-9-ylphenyl)amine (TCTA). To deeply understand the origin of these new bands, single-layer and bilayer TCTA-based OLEDs subjected to electrical and optical (ultraviolet (UV)) stresses were investigated by using various optical, electrical, morphological, and chemical measurements. The results showed that the stress-induced emission bands primarily originate from morphological changes rather than chemical changes.

Light-emitting diodes (LED) for domestic lighting: any risks for the eye?

Light-emitting diodes (LEDs) are taking an increasing place in the market of domestic lighting because they produce light with low energy consumption. In the EU, by 2016, no traditional incandescent light sources will be available and LEDs may become the major domestic light sources. Due to specific spectral and energetic characteristics of white LEDs as compared to other domestic light sources, some concerns have been raised regarding their safety for human health and particularly potential harmful risks for the eye.

[Primary and acquired resistance to antituberculous drugs in strains of Mycobacterium tuberculosis isolated in Rwanda].

This study was undertaken within the framework of a surveillance project on the resistance of Mycobacterium tuberculosis to first-line antituberculosis drugs in four provinces of Rwanda with a high prevalence of tuberculosis (TB). The purpose was to determine the prevalence of primary and acquired resistance of M. tuberculosis to major antituberculosis drugs.

Evaluation of the resazurin microtiter assay for rapid detection of ofloxacin resistance in M. tuberculosis.

Objective: To evaluate the performance of the colorimetric resazurin microtiter assay (REMA) method for the detection of ofloxacin resistance.

Methods: A panel of 120 multidrug-resistant Mycobacterium tuberculosis strains was tested blindly by the REMA method and compared with the results obtained using the BACTEC 460 method.

Result: A very good correlation was observed between the two methods.

Clinical and microbiological features of dientamoebiasis in patients suspected of suffering from a parasitic gastrointestinal illness: a comparison of Dientamoeba fragilis and Giardia lamblia infections.

Objectives: To describe the clinical and microbiological features of Dientamoeba fragilis and Giardia lamblia infected patients, and to analyze the genetic variation of D. fragilis strains.

Methods: For a period of two years, all stool samples collected from patients suspected of having a parasitic gastrointestinal infection were examined according to our specific triple feces test (TFT) protocol.