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1.  Synthesis and electrical characterization of intrinsic and in situ doped Si nanowires using a novel precursor 
Perchlorinated polysilanes were synthesized by polymerization of tetrachlorosilane under cold plasma conditions with hydrogen as a reducing agent. Subsequent selective cleavage of the resulting polymer yielded oligochlorosilanes SinCl2 n +2 (n = 2, 3) from which the octachlorotrisilane (n = 3, Cl8Si3, OCTS) was used as a novel precursor for the synthesis of single-crystalline Si nanowires (NW) by the well-established vapor–liquid–solid (VLS) mechanism. By adding doping agents, specifically BBr3 and PCl3, we achieved highly p- and n-type doped Si-NWs by means of atmospheric-pressure chemical vapor deposition (APCVD). These as grown NWs were investigated by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM), as well as electrical measurements of the NWs integrated in four-terminal and back-gated MOSFET modules. The intrinsic NWs appeared to be highly crystalline, with a preferred growth direction of [111] and a specific resistivity of ρ = 6 kΩ·cm. The doped NWs appeared to be [112] oriented with a specific resistivity of ρ = 198 mΩ·cm for p-type Si-NWs and ρ = 2.7 mΩ·cm for n-doped Si-NWs, revealing excellent dopant activation.
PMCID: PMC3458602  PMID: 23019552
chemical vapour deposition; field-effect transistor; oligosilanes; radiation-induced nanostructures; silicon nanowires; vapor–liquid–solid mechanism
2.  In vitro activity of pyronaridine against Plasmodium falciparum and comparative evaluation of anti-malarial drug susceptibility assays 
Malaria Journal  2009;8:79.
Pyronaridine, a Mannich base anti-malarial with high efficacy against drug resistant Plasmodium falciparum, is currently evaluated as a fixed dose combination with artesunate for the treatment of uncomplicated malaria. In this study, the in vitro activity of pyronaridine against clinical isolates of P. falciparum from Lambaréné, Gabon, was assessed in order to obtain baseline data on its activity prior to its future use in routine therapy. Moreover, follow-up assessment on the in vitro activity of chloroquine, artesunate and quinine was performed.
In vitro response of field isolates of P. falciparum to pyronaridine, chloroquine, artesunate and quinine was assessed using the traditional WHO microtest. In addition, the histidine-rich protein 2 (HRP-2) assay was performed and evaluated for its future implementation for follow-up of drug susceptibility testing.
Pyronaridine exhibited a high in vitro activity against P. falciparum, with a geometric mean cut-off concentration of 9.3 nmol/l. Fifty percent effective concentrations were 1.9 nmol/l and 2.0 nmol/l in the WHO microtest and HRP-2 assay, respectively. Results matched closely in vivo findings from a recent clinical trial on pyronaridine-artesunate treatment. One isolate showed diminished sensitivity to artesunate. For chloroquine and quinine resistance levels were comparable to prior studies from Lambaréné. Results from the novel HRP-2 assay corresponded well to those obtained by the WHO microtest.
Pyronaridine is highly active in chloroquine-resistant parasites and seems a promising partner drug for artemisinin-based combination therapy in Africa.
PMCID: PMC2679051  PMID: 19389221
3.  Randomized Controlled Trial of Fosmidomycin-Clindamycin versus Sulfadoxine-Pyrimethamine in the Treatment of Plasmodium falciparum Malaria▿ † 
Fosmidomycin-clindamycin therapy given every 12 h for 3 days was compared with a standard single oral dose of sulfadoxine-pyrimethamine. The two treatments showed comparably good tolerabilities and had an identical high degree of efficacy of 94% in a randomized trial carried out with 105 Gabonese children aged 3 to 14 years with uncomplicated malaria. These antimalarials merit further clinical exploration.
PMCID: PMC1855537  PMID: 17325227

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