General Solvent-dependent Strategy toward Enhanced Oxygen Reduction Reaction in Graphene/Metal Oxide Nanohybrids: Effects of Nitrogen-containing Solvent.

A general solvent-dependent protocol directly influencing the oxygen reduction reaction (ORR) in metal oxide/graphene nanohybrids has been demonstrated. We conducted the two-step synthesis of cobalt oxide/N-doped graphene nanohybrids (CNG) with solvents of water, ethanol, and dimethylformamide (DMF), representing tree typical categories of aqueous, polar organic, and organic N-containing solvents commonly adopted for graphene nanocomposites preparation. The superior ORR performance of the DMF-hybrids can be attributed to the high nitrogen-doping, aggregation-free hybridization, and unique graphene porous structures. As DMF is the more effective N-source, the spectroscopic results support a catalytic nitrogenation potentially mediated by cobalt-DMF coordination complexes. The wide-distribution of porosity (covering micro-, meso-, to macro-pore) and micron-void assembly of graphene may further enhance the diffusion kinetics for ORR. As the results, CNG by DMF-synthesis exhibits the high ORR activities close to Pt/C (i.e. only 8 mV difference of half-wave potential with electron transfer number of 3.96) with the better durability in the alkaline condition. Additional graphene hybrids comprised of iron and manganese oxides also show the superior ORR activities by DMF-synthesis, confirming the general solvent-dependent protocol to achieve enhanced ORR activities.

Disseminated Fusarium infection in a patient with acute lymphoblastic leukemia: A case report and review of the literature.

Fusarium is a common soil mold. In severely immunocompromised patients, this fungus may cause disseminated disease and is often confused with Aspergillus, as the two pathogens have similar histopathological appearances. Disseminated Fusarium infection may cause significant morbidity and mortality in immunocompromised patients. The current case report presents a 20-year-old male with acute lymphoblastic leukemia who developed disseminated Fusarium infection during induction chemotherapy. Early diagnosis and treatment is extremely important since the mortality rate is extremely high in such patients. The clinician must consider that the clinical presentation of Fusarium infection resembles that of Aspergillus. There is no optimal treatment for patients with Fusarium infection; however, combination antifungal therapy may have benefit without significant toxicity.