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This study investigated a passivation process for polished nitinol wires and vascular stent components, after being given a typical shape setting heat treatment. Heat treated samples were passivated in a nitric acid solution and a series of corrosion tests, surface analysis and chemical analysis was performed. Potentiodynamic polarization tests demonstrated a significant increase in breakdown potential for passivated samples, compared to heat treated surfaces. Surface analysis indicated that the passivation reduces Ni and NiO content in the oxide and increases TiO2 content. Chemical analysis of passivation solutions suggests that the improvement in corrosion resistance is proportional to the quantity of nickel removed. Long term immersion tests demonstrate that nickel release from the surface of the material decreases with time and the quantity of nickel released is lower for passivated samples. The improved corrosion resistance is maintained after extended periods of immersion in saline solution. [Copyright &y& Elsevier]

Offers two teacher-directed activities that will give students a chance to use polar coordinates by naming points in the classroom. Graphing.

Examines the evoked potentials in neurological diagnosis. Usability of visual, auditory, somatosensory evoked potentials for the management of patients with a variety of neurological disorders; Occurrence of abnormalities of evoked potentials; Ability of evoked potentials in providing a means of objective assessment of central nervous system function.

Examines the effect of refractive error on the visual evoked response (VER) of neurological disorders. Attenuation and desynchronization of the response; Changes in latency of positive component in pattern-reversal VER; Reduction of VER amplitude.

Investigates the alpha and beta coma in drug intoxication. Use of electroencephalogram (EEG) in evaluating comatose patients; Prognosis of alpha coma; Domination of EEG by frequencies in the alpha or slow beta range.

Examines the contribution of L-5-HTP sodium valproate and clonazepam in post-anoxic myoclonus. Complications of cerebral hypoxia; Characteristics of L-5-HTP sodium valproate and clonazepam; Nature of cerebral insult in patients with post-anoxic myoclonus.

Highlights • Nine in ten persons in world are exposed to polluted air • There is an associations between air pollution and neurobehavioral deficits acquired in utero, in childhood and adult life • Air pollution contributes to 29.2% of the global burden of stroke • WFN has chosen to emphasize the impact of the environment, notably air pollution, on the brain • There is a need for collaboration between physician professional societies and environmental experts at a global level [ABSTRACT FROM AUTHOR]