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An important issue in construction of organic photovoltaic cells concerns the selective contacts. Here, especially the modification of the hole-extraction is challenging, as energy levels have to match the polymer's highest occupied molecular orbital (HOMO). We took the view to the mutual anode interface and we sought for a solution-based alternative for commonly used PEDOT:PSS – with an eye on improving the hole-extraction with an inorganic interlayer. We present copper iodide (CuI) as a versatile inorganic p-type semiconductor that meets the requirements for enhanced charge extraction in donor polymers. We applied two types of anthracene-containing PPE–PPV block–copolymers that recently gained attention as efficient active absorbers in bulk heterojunction photovoltaic cells. We report on the advantages using CuI as hole-selective contact and show an improvement of the power conversion efficiency in polymer-based solar cells.

Objective: To determine the prevalence and seasonal variation, and to assess the clinical manifestations and treatment of blastocystosis in Libyan patients. Methods: Three thousand six hundred and forty five stool samples were screened for Blastocystis hominis using normal saline and iodine solution preparations. The clinical features of 108 patients were described, in whom B. hominis was the only parasite isolated. Fifty symptomatic patients were treated with 1500 mg metronidazole daily for 7 days and their stools were re-investigated for B. hominis. Results: B. hominis was found in 969 (26.58 %) of 3645 stool specimens examined. The infection of B. hominis was significantly more (p < 0.05) in summer than in winter over a three year period. In a prospective study of 108 patients, the most common symptoms with stools positive only for B. hominis were diarrhoea (84.94 %), abdominal pain (66.66 %), flatulence (17.20 %) and vomiting (16.12 %). High concentration of B. hominis cells were found more in symptomatic patients than asymptomatic ones (9.20 cells per 40 X field versus 4.06 respectively) with statistically significant differences (p < 0.001). Patients with B. hominis responded to metronidazole and were fully cured after 7 days. Conclusion: The occurrence of B. hominis infections in outpatients are probably related to weather conditions, with the suggestion that the hot, dry weather of the Sebha region favors the development and transmission of this organism. B. hominis infections might have a role in some pathological conditions, resulting in gastrointestinal symptoms.

International audience; The soil and water preservation requires new sensitive techniques. Raman probe was recently shown to be an interesting alternative to electrical sensors to detect several contaminants diluted in water. Here we report on the procedure to reliably determine the substance concentration within a fairly good accuracy and a high speed.

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The aim of the present study was to prepare resorbable hydroxyapatite (HA) based bone graft materials reinforced with carbon nanotubes as a way to cope with the inability of pure HA to resorb and its intrinsic brittleness and poor strength that restrict its clinical applications under load-bearing conditions. With this purpose, a Si-doped HA nanopowder (n-Si(0.8)HA) was prepared by chemical synthesis and used as composite matrix reinforced with different amounts of functionalized multiwall carbon nanotubes (MWCNTs). The effect of the added amounts of MWCNTs on the mechanical properties of nanocomposites and their in vitro biomineralization was assessed by bending strength measurements, immersing tests in simulated body fluid solution (SBF), scanning electron microscopy (SEM), and inductively coupled plasma atomic emission spectroscopy analysis (ICP-AES). The bioactivity and bending strength were enhanced, reaching maximum balanced values for an optimum addition of 3 wt.% f-MWCNTs. These results might contribute to broaden the potential applications of HA-based bone grafts.

International audience; Raman probe can be used to detect substances dissolved in water. Here are reported and discussed some experimental and data treatment processes needed to identify species and also to determine their content in a mixture. A particular attention is paid to the treatment of Raman line intensity used in the calibration of the probe.

International audience; Raman spectra of potassium, sodium, and ammonium sulfates (K2SO4, Na2SO4, and (NH4)2SO4) are reported and analyzed. These sulfates have been investigated under two states: solid (anhydrous and hydrated) salts and aqueous solutions. The effects of monovalent ions (K+ , Na+ , and NH4+) and hydration on the position of Raman lines assigned to internal vibrations of sulfate anion SO42- are discussed. In solid salts, the line position of each Raman peak is shown to decrease with increasing radius of the cation. The main ν1 mode of sulfate molecule is particularly affected. It is emphasized that this sensitivity in solid sulfates vanishes in aqueous solutions. As a consequence, this mode can be probed by Raman spectroscopy as the main signature of SO42- to determine its concentration within a single calibration.

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International audience; We propose to detect by Raman spectrometry the presence of chlorid anion in mixtures of salted solutions. Here is shown how Cl-influence the OH stretching band of the water spectrum and how its concentration is determined using chemometrics methods applied on Raman spectra recorded on mixtures in few seconds.

International audience; The paper is devoted to the abilities of Raman probe to detect simultaneously several salts diluted in water. It has shown that this probe can be used for in situ monitoring of pollutants in waste water.

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International audience; The control of the quality of water is a growing need in our modern societies in order to insure the access of water in healthy conditions to an always rising number of people through the world. This leads to the obligation to detect all pollutants in flow water, rivers, basins, lakes… [1]. This challenge requires new and efficient techniques which are able to provide in situ and quick measurements. Nitrates, sulphates, and phosphates have to be specially purchased since they are very water soluble and lead to negative incidence in the environment. They arise generally from pesticides used in agriculture [2,3]. Techniques generally used for pesticide detection are chromatographic methods like gas chromatography high performance liquid chromatography and mass spectrometry. They are relatively sensitive and reliable. However, they had limitations like complex procedure, time consuming sample treatments, and inability for on site detection. Here, we investigated the abilities of Raman probes to detect simultaneously the presence of several pollutants dissolved in water and to determine their concentration as well. Measurements have been done with a 532 nm exciting line using a spectrometer Kaiser RXN1. In Figure 1, one can see that an own signature can be detected by Raman probe for each kind of anion in different spectral ranges. As a consequence, the concentration of each salt in water can be deduced from an appropriate calibration.

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