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Anodic polarization of carbon steel electrodes in deaerated 0.01 mol L −1 NaCl + 0.01 mol L −1 NaHCO 3 + 0.001/0.01 mol L −1 Na 2 S solutions (with pH ∼ 7.5) led to heterogeneous layers made of magnetite and mackinawite. A locally accelerated dissolution of the steel was observed in any case and the most corroded areas were covered with a layer enriched with mackinawite. This suggests that part of the electrode surface was blocked, covered with a magnetite rich layer where water reduction was favored. The effects of the galvanic coupling between a magnetite electrode and a bare carbon steel electrode covered with a ∼5 mm thick argillites layer were then studied in a 0.01 mol L −1 NaCl + 0.01 mol L −1 NaHCO 3 solution at room temperature and 80 °C. Electrochemical measurements demonstrated that a relatively high galvanic current initially flowed between the magnetite electrode (cathode) and the steel electrode (anode). However, this current decreased with time down to negligible values. Micro-Raman spectroscopy analysis revealed that a magnetite layer was formed on the steel electrode, thus suppressing the initial difference between anode and cathode. When the same experiment was performed with the steel electrode set under an argillites layer enriched with Na 2 S, the galvanic current density remained constant at a significant value (∼20 μA cm −2 ) during the 11 days of experiment. It led to the formation of a layer composed of mackinawite (and chukanovite) on the steel electrode. This result confirms that heterogeneous magnetite/mackinawite layers can favor galvanic corrosion even in anoxic conditions. [ABSTRACT FROM AUTHOR]

Ionic magnetic fluid (ferrofluid) is a stable suspension of magnetic nanoparticles in water. Cobalt ferrite nanoparticles are interesting in view of high-density recording storage. The size of the magnetic particles strongly influences the physical properties of the ferrofluids. In this study, we describe the synthesis of ionic magnetic fluid in the presence of tartrate ions. By varying the amount of organic ligands, nanoparticles in a large range of size are obtained: the mean diameter varies from 3 to 10 nm. The effect of tartrate ions on the stability of the ionic magnetic fluid is also studied in relation with the size of the magnetic particles and the amount of adsorbed ligand. [Copyright &y& Elsevier]

Aims: The study aimed for evaluate the efficacy of Pseudomonas knackmussiiMLR6 on growth promotion, photosynthetic responses, pigment contents and gene expression of the plant model Arabidopsis thaliana under NaCl stress. Methods and Results: The strain MLR6 was isolated from the rhizopshere of the halophyte Salsola tetrandra collected from a natural saline Algerian soil. Results showed the ability of MLR6 to induce plant growth‐promoting traits even under NaCl stress. The inoculation with MLR6 improved the stomatal conductance, the transpiration rate, the total chlorophyll and carotenoid contents under salt stress. It conferred also an increase in fresh/dry weight as well as plant height. MLR6 inoculation further provided a positive effect on cell membrane stability by reducing the electrolyte leakage and priming the ROS accumulation after the salt exposition. Additionally, the expression of NHX1,HKT1,SOS2 and SOS3 as well as SAG13 and PR1 was maintained in MLR6‐bacterized plant at a similar level of controls. Conclusions: The inoculation of A. thaliana with MLR6 improves plant growth and reduces damages caused by salt stress. Significance and Impact of the Study: The use of P. knackmussiiMLR6 appears as a promising strategy to improve the sustainable agriculture under saline conditions. [ABSTRACT FROM AUTHOR]

Kawasaki disease (KD) is an acute vasculitis characterized by marked tropism of the coronary vessels. Usually a childhood disease, KD can occasionally be observed in adults. We report a case of adult-onset KD that presented as a prolonged fever of unknown origin with subsequent development of severe vasculitis, manifested by coronary aneurysms and peripheral gangrene of the lower limbs. Therapy with intravenous immunoglobulins, corticosteroids, aspirin, anticoagulants, and prostacyclin analogue resulted in rapid improvement in the patient's condition but he required partial distal amputation for irreversible gangrene. Peripheral ischaemia leading to gangrene is a very rare feature of KD vasculitis with only 19 cases previously published in the Medline-indexed literature. The outcomes of those patients were poor, being either fatal or requiring distal amputation. All prior cases affected young children less than 1 year old and, to the best of our knowledge, the present case is the first description of peripheral gangrene in adult-onset KD. [ABSTRACT FROM AUTHOR]